18650 lithium ion cell test

4800mAh, 5200mAh, 6800mAh, 8800mAh in one LiIon 18650 battery!?

4800mAh, 5200mAh, 6800mAh, 8800mAh. With such "fantastic" characteristics, 18650 batteries are sold in stores in our city!
The emergence of such powerful lithium-ion battery cells in the 18650 battery cell market could not interest us. Even the leader in the production of LiIion batteries, Panasonic, which produces the NCR18650G with a capacity of 3400 mAh, looks very faded next to them. We decided to conduct a test and publish the results!
With the help of a software and hardware complex for testing battery cells, we can emulate various operating conditions for battery cells: charge, discharge, with different currents and voltages.
Just like when testing batteries, we also tested LiIon 18650 3.7V battery cells for the amount of energy output and its cost. In other words, we found out which 18650 cells are profitable to buy, and which 18650 batteries have electricity cheaper or more expensive.
We tested all elements according to the following scheme:
1. Charge the battery cell to a voltage of 4.2 volts.
2. Rest the element without load and without voltage for 5 minutes.
3. Discharge of the element to a voltage of 2.75 volts with a current of 0.5 amperes.

In different retail stores in the city of Irkutsk, we purchased 1 piece of each model: *
- HANGLIANG 18650 6800mAh - Price: 250 rub.
- BAILONG 18650 8800mAh - Price: 380 rubles.
- UITRAFLRC 18650 4800mAh - Price: 250 rubles.
- XBAL G 18650 8800mAh - Price: 350 rubles.

For comparison, the following were used in the experiment: *
- - Price: 225 rubles.
- China ISR18650P 2200mAh - Price: 280 rub.
- - Price: 300 rubles.
- SAMSUNG ICR18650-24E 2400mAh used - Price: free of charge for the promotion.

Cell test results
LiIon 18650 3.7 volts,
discharge up to 2.75 volts, load 500mA.

	price, rub.	Battery discharge time up to 2.75 volts, h:m:s	Received battery capacity, mAh	Cost of 1Ah, rub.
China ISR18650 1300mAh Power	225	2:32:06	1317,59	0,17
China ISR18650P 2200mAh	280	4:25:08	2292,56	0,12
LG LGABB41865 2600mAh	300	4:57:04	2572,04	0,12
SAMSUNG ICR18650-24E 2400mAh used	free of charge	2:52:40	1494,14	0,00
HANGLIANG 18650 6800mAh	250	0:02:49	473,00	0,53
BAILONG 18650 8800mAh	380	0:35:45	309,55	1,23
UITRAFLRC 18650 4800mAh	250	1:01:30	532,19	0,47
XBAL G 18650 8800mAh	350	1:04:12	555,78	0,63

*prices indicated at the time of writing, June 2016.

After test opening

When testing, we noticed the low weight of elements from HANGLIANG, BAILONG, UITRAFLRC and XBAL. On average, the weight of one element was only 25 grams. Usually 18650 cells weigh about 40-45 grams.
We opened one of the elements. Approximately 1/4 of the battery was free. The winding of the electrode is not dense, it has interlayer gaps.
Thus, we can conclude that one of the signs of a battery with a fictitious capacity is the light weight of the element with a capacity of more than 2500-3000 mAh indicated on it.

To answer the question of what a 18650 battery is used for or how it is also called - 168A, we will study its characteristics and capabilities, as well as examples of use in a domestic environment.

This type of battery is currently quite popular for a number of reasons, but the main ones are a voltage of 3.7-4.3 volts and a good capacity (working time) up to 3600 mAh, as well as a fairly compact size.

They are similar in shape to AA batteries and AAA batteries, but larger in size. As mentioned above, the output voltage of these batteries is 3.7 - 4.3V Capacity 2200-3400 mAh.

For AA and AAA finger batteries, the voltage is 1.5V

Ni-MH ( nickel-metal hydride) AA and AAA-1.2V batteries.

Schematic device Li-ion battery

Li-ion battery capacity 18650

Energy capacity is the amount of energy that is stored in a battery. Battery capacity, often expressed in watt hours (Wh, Wh), kilowatt hours (kWh), or ampere hours (Ah, Ah). The most common measure of battery capacity is Ah, defined as the number of hours a battery can deliver current equal to the discharge rate at the battery's rated voltage. A watt hour is the voltage (V) that a battery can provide multiplied by the amount of current (amps) that a battery can provide for a period of time (usually in hours). Voltage*Amp*Hours = Wh. Since the voltage is highly dependent on the type of battery due to its internal chemistry (alkaline, lithium, lead acid, etc.), often only amp*hour data is displayed on the side of the battery, expressed in Ah or mAh (1000 mAh = 1 Ah). To get Wh, multiply Ah by the rated voltage. For example, suppose we have a nominal 3V battery with a capacity of 1Ah or 1000mA*h, its power will be 3W.

1 A*h means that in theory we can use 1 amp for one hour or 0.1A for 10 hours or 0.01A (10mA) for 100 hours.

IMPORTANT! At the time of this writing, there are NO batteries with a capacity higher than 3600 mAh in size 18650 !!!

18650 battery size

Deciphering the digital designations of the 18650 battery:

the first two digits (18) are the diameter;

the next pair of digits (65) is the length;

the last digit (0) indicates the shape of the battery, in this case a cylinder.

As you can see after measurements, the length of the cheapest Chinese battery brand UltraFire (manufacturer of cheap Chinese flashlights) 18650 format is 66.5mm, and the diameter is 18mm.

Compare the dimensions with other types of batteries:

AAA: 44.5 x 10.5mm

AA: 50.5x14.5mm

14500: 53 x 14.5mm

18650: 65.5 x 18 mm (unprotected)

18650: 67.5 x 18 mm (protected)

26650: 67.5 x 26.1mm

Visual comparison of AA, AAA and 18650 batteries.

And although the 18650 battery resembles finger and little finger batteries, it will have a larger size.

What is a protected battery

18650 batteries come with and without protection - if the 18650 battery does not have protection, then there are no additional inscriptions on it, or there is an “Unprotected” inscription. The length of the unprotected (without a full discharge or overcharge protection board) is 66.5 mm.

If the description of the battery contains the inscription "With Re / Discharging Protection Circuit" (protection from full discharge / overcharging), "Protected", "With protective PCB", "Protection Circuit", etc., then the battery has a protection board on board. A small thickening (usually a 1mm plate) near the contact is the battery protection board.

For reliable operation and avoiding damage, complete discharge or overcharging and overheating, Li-Ion batteries must operate within the voltage range of 4.2-2.5V.

One of the weak points of Li-ion batteries is that they are subject to failure during recharging and / or overheating, as well as when they are completely discharged. After that, it will be problematic to restore or charge the battery or it will lose its initial capacity. With careless handling lithium-ion batteries may fail more often than other types of batteries.

This problem is solved, as noted above, by installing an electronic protection circuit that prevents excessive overcharging and / or overheating as a result of exceeding the permissible current during charging, and also interrupts the circuit when the charge is low, protecting the battery from deep discharge during its operation. This protection board not only ensures that the battery operates within the permissible safe voltage range, but also prevents overcurrent and short circuits. The protection board with a steel conductor is spot welded to the corresponding battery contacts. In fact, it looks like this: on the negative contact of an unprotected Li-Ion battery (“cell”), an electronic protection board 1-3mm thick and under the battery diameter is installed.

The length of such a battery is slightly longer - an average of 67.5-70mm versus 65-66mm for an unprotected one. When the battery voltage rises above 4.25V, the protection board blocks further battery charging in order to prevent it from being damaged during overcharging and overheating. The same thing happens at a voltage of less than 2.75V - the protection board blocks further battery discharge below the specified threshold.

Typically, major manufacturers of Li-Ion batteries do not produce batteries with built-in protection. They produce only unprotected batteries. As a rule, there are no protected Li-Ion batteries of the SAMSUNG or Panasonic brand, which would be released specifically by "Panasonic in Japan" or "Samsung in Korea", and those who prove the opposite are intentionally or unintentionally trying to introduce you astray.

Protected batteries are assembled from ordinary Li-Ion batteries (cells) with the subsequent installation of a protection board.

The assembly process can take place in different ways: as a rule, the assembly of batteries with protection is carried out at enterprises in China. But China is different - there is both frank counterfeiting and amateurism on the part of little-known battery manufacturers (with imaginary capacities from 3800mAh to infinity) and very high-quality products from well-known brands.

Batteries with protection are assembled and sold by completely different brands that are not related to the manufacturer of the batteries themselves. The battery assembled at the factory with protection is covered with a thermal shell with the brand name and an indication of the capacity (sometimes real and sometimes absolutely fantastic).

Due to the fact that the 18650 battery with protection is 1-3 millimeters longer than its unprotected counterparts and sometimes 0.5 mm thicker in diameter.

Extended batteries with protection can be of size 18700, and size always matters - such a battery may not fit into the battery compartment of some consumer devices. Therefore, when choosing a protected battery, you should think about whether it is suitable in length, for example, for your LED flashlight, charger, etc.

Mechanical - internal protection of Li-ion batteries

In addition to protection using the charge controller board, the battery can use an internal-mechanical battery protection system. The internal protection function consists in the operation of a special mechanical switch as a result of the temperature threshold (overcharging / heating) and pressure inside the battery that has increased to critical values ​​\u200b\u200bwhich can lead to an explosion. The battery is disconnected by a mechanical break in the circuit by the internal protection of the power supply. If this does not help and the temperature with pressure continues to rise further, then the pressure relief valve is activated, which releases gases and electrolyte to the outside.

The mechanical switch itself is quite widespread as a primary or secondary safety measure in many batteries, operating in conjunction with a charge controller (board) or without it. It is worth noting that the presence of internal protection will not necessarily be mentioned on the case or in the description of the technical characteristics of the product. As a rule, well-known manufacturing companies will not neglect the internal-mechanical protection of their power supplies with an unstable chemical composition, with the possible exception of the cheapest and little-known Chinese brands. Therefore, regardless of whether an electronic protection board is present or absent in any power source, it must have built-in physical protection.

The use of protected and unprotected Li-ion batteries

18650 batteries are usually used where a long time is needed battery life with a compact size.

Both unprotected and protected batteries can be used in any devices or devices designed to work with Li-Ion power sources, the only difference is that if the device or device do not have a built-in charge-discharge controller, then this disadvantage can be compensated by a protected power supply.

The main devices where Li-Ion batteries are used today are LED lights and lamps, since it is these batteries that have sufficient power and capacity to ensure continuous and uninterrupted operation of high-power LEDs of the latest generations in these devices.

In our particular example, these are LED lights with diodes of the latest generations XM-L / L2, XP-L / L2, etc. (Сonvoy s2 +, Сonvoy c8).

This flashlight has an AAA battery installed.

This flashlight is powered by an AA battery.

And these lamps are equipped with LEDs of the latest generations CREE XM-L2, XP-L2. They need a lot of power to work. That is why these flashlights are powered by an 18650 battery and are made for it, as it is ideal for this purpose.

Some cheap Chinese brands such as UltraFire flashlights are designed so that the 18650 battery can be replaced with 3 finger batteries AAA format through a special adapter. In this case, the voltage is almost the same: 3.7V and 4.5V (= 1.25V * 3 or 1.5V * 3).

In most cases, for simple Chinese UltraFire LED lights, a protected battery is required.

It happens that for some batteries the current protection is too sensitive, and works at less than acceptable values. In this regard, the lights on powerful LEDs of the latest generations XM-L/L2, XP-L/L2 do not function properly. When the flashlight is turned on, an overcurrent occurs - the battery protection is activated, the flashlight may blink and no longer show signs of life. When you change the battery to an identical one, it can be the same, protection is instantly triggered. There are two options here - either remove the protection board and use the battery without it, or replace the battery with another - a time-tested brand.

As mentioned above, battery protection definitely increases the length of the battery by 1-2 mm, or even more. If a Li-Ion battery with protection reaches a length of 7 cm, for some compact flashlights designed to install a Li-Ion battery, it is impossible to screw the back cover and you have to look for a battery without protection or remove it again. The longer the battery - the greater the force of the springs on it in the battery compartment; it happens that they push through the negative contact of the Li-Ion battery. Most often this happens when the flashlight is used as an underbarrel, during recoil when fired. Yes, and it is not very pleasant to push such a battery into the battery compartment of the flashlight with force twisting the cover, scratching and damaging the battery contact with the spring.
But whatever the protection of the battery, it does not 100% guarantee the safety of the battery and the flashlight from overheating and even explosion.

Usually the increased pressure in the accumulator is vented through special openings in the accumulator valve, but in the sealed space of the flashlight they may not help.

In principle, if you know the approximate effective operating time of a Li-Ion battery based on its capacity in a particular consumer, then you can safely use unprotected batteries. Many people do just that. This applies to single battery flashlights. If multiple batteries are used, protection must be mandatory.

It happens that the protection board fails. To restore further use of the battery without it, do the following:

Remove the polymer coating (shell);

A positive conductor is visible on the case, going to the protection board, which is simultaneously soldered by spot welding to the case (minus) of the battery. In the event of critical current and voltage values, the protection board breaks this circuit;

The protection board is removed, freeing it from spot welding. Remove the conductor;

Remove the shell around the negative terminal so that the contact is available for connection to the final consumer devices;

Instead of a native shell, you can use ordinary adhesive tape or electrical tape or a self-adhesive film of any color, cutting out a piece from it to fit the battery and carefully pasting it over it. With such a film, the battery will become unique, especially if you wrap it in carbon film. :-)

After removing the protection board, the battery will lose 1-3 mm in length. And it will become an ordinary battery without protection.

If, for example, you need to repair the battery in a laptop, upgrade the battery in a screwdriver, or you need a prefabricated BATTERY from Li-Ion batteries, then for this you need to use unprotected batteries.

Pros and cons of lithium-ion batteries

Usually 18650 battery is li-ion th battery.

The main advantages of Li-ion batteries are:

High energy density;

More high voltage(compared to NiCd and NiMH batteries);

Low self-discharge 4-6% per month, 10-20% per year;

No "memory effect", the need for "training" after purchase - it is not necessary to fully charge and then completely discharge lithium batteries after purchase;

Wide operating temperature range - from -20 to + 50 °С;

Large operational resource of about 10 years;

A significant reserve of working cycles discharge-charge more than 1000;

Ease of maintenance;

Low specific gravity.

A few disadvantages of Li-ion batteries:

Relative high cost (every day this minus disappears);

Low resistance to overcharge and full discharge, so smart Li-Ion batteries are equipped with built-in systems automatic shutdown;

Non-limitless range of operating temperatures (from -20 to + 50 C) performance deterioration at high temperatures, capacity reduction when used in cold weather;

Difficulty charging at low temperatures;

Explosion hazard if the body is damaged by a puncture or other violation of tightness;

Dependence of service life on time, and not on the number of discharge and charge cycles, there is a gradual loss of capacity over time

Storage of Lithium Polymer and Lithium Ion Batteries

Lithium-Polymer and Lithium-Ion batteries reduce capacity, unlike Nickel and NiMH batteries, when subjected to a charge. The higher the battery charge and storage temperature, the shorter its service life. Overcharging, like overdischarging, "burns out" the capacity of the battery.

The optimal storage conditions for Li-ion batteries are:

• 40-50% charge from battery capacity;
• temperature 0-10 degrees Celsius.

At the same time, low temperature is a more important factor for small capacity losses during long-term storage. The average shelf life (service life) of a lithium battery is an average of 36 months. Lithium batteries age even if not used.
(Wikipedia).

To extend the life of a lithium battery and increase its efficiency, you need to follow simple recommendations:

avoid complete discharge of the battery, regularly recharge it when the charge level drops to 20%;

do not allow the battery to overheat and expose it to direct sunlight;

do not use the battery in severe frost, insulate it for operation in winter;

store a lithium-ion battery with a 50% charge level, at a temperature of 0 C;

protect the battery from shock, damage and strong vibration; when installing on electric vehicles, put a soft layer

Deciphering markings and inscriptions on batteries

In mass production, three classes of Li-ion batteries are used (the cathode material is taken as the basis, the second letter in the marking):
1) lithium-cobalt LiCoO2 (the most common, the highest capacity among Li-Ions)
2) lithium-manganese LiMnO2, LiMn2O4, LiNiMnCoO2 (better known as high-current (INR), capable of delivering currents of 5-7C to the load, usually inferior in capacity to the first)
3) lithium ferrophosphate LiFePO4 (excellent batteries underestimated by the market, undeniably outperforming the first two types in all respects, except for the operating voltage and capacity, it is even lower than that of INR)
As they say, all three classes are tailored to perform specific tasks, have their pros and cons.

Since there are no uniform standards for marking batteries, all manufacturers label differently. But ideally it should be something like this:
1) the first letter is manufacturing technology (I - lithium-ion technology)
2) second letter - type of chemistry, cathode material (C/M/F - cobalt/manganese/iron phosphate chemistry)
3) the third letter R - battery (rechargeable)
4) five digits - form factor (the first two digits are the diameter, the next two are the length, the last digit is the shape of akka (0 - cylindrical))
- 10440 (the usual "little fingers")
- 14500 (the usual "fingers"),
- 16340 (size like a CR123 battery),
- 17335 (not common)
- 18500 (also not very common)
- 18650 (the most common form factor on the market),
- 18700 (unofficially, 18650 battery + protection board, i.e. protected battery),
- 26650 (increased, came to the market with the filing of the company A123 Systems, which produces lithium-ferrophosphate batteries)
- 32650 (quite monsters, only for stationary devices, weight is almost 150g)
- plus unofficial f / f with protection boards, for example 18670 ...
5) letters / numbers - specific marking of the container (all manufacturers have different ways)

An example of marking, but as a rule, all manufacturers have different ways:
- Samsung ICR18650-26F (lithium-ion battery with the usual cobalt chemistry, f / f 18650 with a capacity of 2600mah)
- Samsung INR18650-20R (lithium-ion battery with manganese chemistry, i.e. high current, f/f 18650 with a capacity of 2000mah)

Own designations:
Panasonic NCR18650PF (NCR is a kind of cobalt chemistry, something in between the first and second class, i.e. in simple terms chemistry of LiNiCoO2, without the use of magnesium. No matter how it fits a certain class, it turned out to be a kind of symbiosis. Of the benefits - high energy density with low thresholds up to 2.5-2.75V). This battery uses LiNiMnCoO2 chemistry, that is, it is already high-current IMR based on manganese, but the manufacturer left the old marking.
Sanyo UR18650FM - the information may not be accurate, but I have seen information that Sanyo does not produce batteries for retail sale, and therefore does not bother with labeling. She stamps cans for large electronics manufacturers, so the marking is purely “for herself”. Perhaps, according to the internal designations of the company, UR and F (M) means type, chemistry and capacity, at least there is no information in the datasheets (only that this is a model marking). And so this is a lithium-ion battery with the usual cobalt chemistry, f / f 18650 with a capacity of 2600mah.

Choosing an 18650 Battery

Now, after we have studied the main characteristics of batteries, let's try to figure out how not to make a mistake when buying a battery and what type to choose for specific tasks. Many of us use flashlights and lamps on 18650 batteries, and someone also has power banks for these types of batteries.
You should never take a word on the inscriptions on batteries of unknown, little-known or cheap brands.

A good example of a battery with a fantastic capacity

A person who does not understand will immediately fall for this - this is a fact. Be carefull!

Choosing an 18650 battery. Q&A

If you need simple advice - which 18650 battery is better to buy without delving headlong into the technical component, “so that it just works fine”, we will answer like this:

The most affordable in terms of price / quality ratio is the Samsung ICR18650-26F (or H) with a capacity of 2600mAh, most of your devices and flashlights will work on it without problems.

If you increase the budget for the purchase of a battery by one and a half to two times, you can purchase an almost limiting capacity LG18650MJ1 battery (30% more):

Its analogues are Sanyo (NCR18650GA) and Samsung (INR18650-35E) and Samsung is much cheaper.

If you need a record holder in terms of capacity and quality, then this is definitely what we think at the moment Panasonic NCR18650G 3600mAh

Protected and/or unprotected 18650 battery?

Attention! All items on this list are required!

We are talking about electronic protection against overcharge, overdischarge and short circuit. Details with pictures.

Batteries with protection must

• A lantern consists of two or more successively installed batteries. "Lantern-baton", like this.
• You are using a simple charger without overcharge protection circuitry and/or from obscure Chinese manufacturers.
• The flashlight is equipped with mechanical protection against reversal of the polarity of an incorrectly installed battery. For this, a battery with protection with a protruding positive contact is usually used (of course, exceptions are possible).
• The flashlight does not have information or shutdown protection in case of a significant battery discharge - below 2.6 V, and you do not want to bother with this (it's corny you can just forget to turn it off).
• The flashlight can be temporarily used by forgetful and / or inexperienced people, as well as into the hands of your children and they will torture it until they lose their “pulse”).

Batteries with protection Can

• For flashlights powered by 18650 batteries, if the protected battery fits freely into it in length (there are no problems with screwing the battery compartment cover) and in diameter (does not rest against the walls during installation).
• Powerful flashlight with parallel connecting two or more batteries. In our opinion, this is a controversial decision.

Unprotected batteries must be used in the following cases:

• Too narrow or short battery compartment in a flashlight designed for one 18650 battery(important!) (the inability to install a protected battery that is 2-3mm longer in length and 0.5mm in width).
• As a rule, a modern flashlight with powerful LEDs (xm-l2 xp-l2) powered by one The battery draws a lot of current at maximum brightness (3 amps or more). And many protected batteries can simply shut down when turned on due to overcurrent.

Unprotected batteries Can use in the following cases:

1. The flashlight is designed for one battery or it works on two or more parallel installed batteries.
2. A smart (smart) charger is used (smooth decrease in the battery charge current and the function of automatically turning off the battery after charging, selection of the charging current, other functions) from trusted brands (liitokala, nitecore)
3. You never forget to turn off the flashlight after use and/or leave it on for long periods of time unattended (unless it has built-in low battery protection).
4. Children do not have access to the Lantern and / or you do not trust others to use it without your presence.
5. You store batteries in a special box and do not throw them anywhere, in connection with which they can be accidentally shorted by metal objects or random current conductors.

Proprietary and / or Chinese 18650 battery?

Previously, purchasing a cheap Chinese (from a true Chinese brand) 18650 battery was justified. A few years ago, such batteries were much cheaper than branded ones, and in terms of characteristics they were close to their branded counterparts.
But time goes by. And starting from 13-14, some well-known brands, in order not to be left out, reduced the price so much that the purchase of a "people's" battery from China of dubious quality in order to save money became irrelevant.
In 15-16 years, super capacious batteries, one can say the flagships of the Panasonic 3600, due to fierce competition from Korean brands, reduced the price almost to the level of Samsung, which had become popular at that time.

Therefore, a Chinese brand - a manufacturer of 18650 batteries (Even if it is already quite popular) can be said: who are you? let's goodbye.

When choosing a battery, do not forget about this:

• There are only four main manufacturers of 18650 batteries from well-known brands: Panasonic, Sanyo, Samsung and LG. There is also Sony with its exotic models, but the ones mentioned above are the most common.
• All other brands (usually these are manufacturers of various flashlights) wrap the same Panasonic, Sanyo, Samsung and LG in thermal covers with the names and logos of their brand, well, maybe even providing these batteries with a protection board and / or modified contact pads.
• As a rule, after that, they noticeably receive an increase in price, although they are no better in terms of performance.
• True, it is worth noting that sometimes such modified batteries can be better than their donors, since they should work seamlessly with flashlights from the manufacturer of the same brand (there may be problems with others due to size, contacts and current overloads).
• For some "special" flashlights, you need to purchase batteries that are recommended by the manufacturer or specified in the description / instructions for the flashlight.

Capacity selection18650 battery

At the time of writing, a large capacity according to real measurements has only one type of battery: Panasonic NCR18650G 3600mAh. What is more (there are fantastic inscriptions 4000, 5200, 9800 and even 12000!), and sometimes even quite real ones from little-known / unknown Chinese brands in fact black marketing and blatant lies our Chinese "friends" of underground production. Usually, with the help of bright labels and super inscriptions, a “pig in a poke” is hidden. On the fonarevka.ru forum, read the article Horrors of our town. In the best case, you will get working junk with a capacity of 1800-2000 mAh and a lifespan of six months to a year.

But even a branded battery with a really high capacity is not a panacea. It happens. that the duration of the flashlight does not always noticeably increase with the installation of the battery increased capacity and there are reasons for this. In everyday living conditions, the Samsung battery with a capacity of 2600 mAh can easily cope with the tasks. This is a workhorse at an affordable price for any conditions. If you are still leaning towards higher capacity batteries (2800, 3200, 3400 and 3600mAh), stick to the following rules:

• Purchase batteries only from well-known brands and manufacturers.
• Popular Panasonic brand Li-ion batteries are capable of giving up their entire capacity when they are discharged to 2.5 v. The truth is worth noticing. that not all flashlights and powerbanks are capable of working with such a low voltage. All “baton flashlights” (with 2-3 18650 batteries installed in series) and flashlights of high-quality Chinese and other brands (Convoy, etc.) powered by a single 18650 battery will cope with this.
• If you use high-capacity batteries from LG or Samsung, then they need to be recharged to their working non-standard voltage of 4.35V (4.2V is considered the standard voltage), most likely using an expensive “smart” charger. An example of such a battery is the LG ICR18650E1 with a capacity of 3200mAh.
• The battery LG INR18650-MJ1 with a declared capacity of 3500mAh is physically able to work for a long time and quietly giving a large current to the load. At the same time, its operation is carried out in the range of standard voltages of 4.2 - 3.0V Li-ion batteries. The analogues of this battery are: Sanyo (NCR18650GA); Samsung (INR18650-35E).

From the foregoing, we can assume that if any of these conditions for the functioning of more capacious and expensive batteries are violated or not met, you will most likely get the same effect from their use and duration of operation as from the cheaper Samsung 2600. Be that as it may from the most capacious and most expensive with an ideal scenario and luck - it will shine only 10-30 percent longer than usual!

Estimated price in Chinese online stores at the time of this writing is $2-2.5 for one can of Samsung 2600mAh and $4-6 for a can of the most capacious Panasonic 3400mAh - 3600mAh. Good, high-quality protection will add another 1-3 dollars. You will have to pay a few more dollars for a beautiful wrapper from a lamp manufacturer.

The meaning of the inscriptions in English in the description of the battery 18650

• The battery capacity is marked " mAh". mAh - milli-ampere-hour in translation into Russian, you guessed it.
• Protected batteries are marked " With protective PCB", "protected", "Protection Circuit" and so on..
• Nothing is indicated on unprotected ones, or in rare cases they indicate " Unprotected".
• Voltage numbers 3.6V and 3.7V essentially mean absolutely the same. Represents the average voltage for a battery that needs to be charged up to 4.2V. Specify either one or the other value, the manufacturer usually decides for himself.
• If the voltage is indicated on the label or in the description 3.8V then this means that the battery should be charged to non-standard 4.3 or 4.35 volt.
• voltage value 3.2 V usually denote Lithium iron phosphate battery . If you have not heard of this and do not know for what purpose it is, just forget about it, most likely it will not be useful to you.

Cases of counterfeit 18650 batteries

There were almost no cases of counterfeit batteries from the line of major brands: Samsung, Sanyo, LG and Panasonic. But with other brands you need to be careful - the situation may be different.

Attention! There have been cases of unscrupulous sellers selling old, worn-out batteries from the dismantling of large batteries from electric cars or electric bicycles.

You can determine the date of manufacture by the manufacturer's code on 18650 batteries at this link:
https://batterybro.com/18650-date

Suitable for:
Samsung
Sony
Panasonic
Sanyo
LG

Signs of such batteries:

• remnants of remote resistance welding on the poles (scratched points on the ends)
• residual sealant (glue) on the battery case

Applications

Table of characteristics for well-known brands

			Marking	Charge voltage	end voltage	discharge current A continuous (maximum)
						6.4-2C(10-3C)
						6.4-2C(10-3C)

	Manufacturer		Marking

Materials used in the article

P.S. From myself I will add as a person who has been using this type of battery for a long time - Take Liitokala, Sanyo, LG, Samsung or Panasonic!

IN NO EVENT DO NOT TAKE UltraFire or worse, and even more so with a capacity above 3000mAh

A variety of household appliances are most often powered by batteries. The 18650 type battery is most suitable in this case. These are unique products with a number of advantages. Often they are used in electronic cigarettes, LED flashlights. What types are there and their features can be found in this article.

18650 battery: what is it and its types

18650 type battery

The 18650 is a lithium-ion type battery, similar in shape and size to a AA battery. The capacity of this type ranges from 1600-3600 mAh, the output voltage is 3.7 V. To better understand the features of such a battery, you should compare it with a standard AAA or AA battery. Its voltage is 1.2 or 1.5 V.

Batteries of the described type are used to bring into operation equipment that requires elements with a large capacity. For example, it is an electric bicycle, portable phone charger, laptop, flashlight and so on.

Note! The battery life is quite long. In order for the device not to deteriorate, its charge should be 50%. It is in this form that the product can lie for about a month. The battery should be stored in a room with a moderate temperature (too high or low readings adversely affect the device). +15 - +17 degrees are optimal.

Many are wondering what the numbers 18650 mean. In fact, everything is very simple. The first two digits are the diameter, 65 is the length of the battery in millimeters.

There are the following types of 18650 batteries depending on the chemical index:

1. Lithium-manganese (Lithium Manganese Oxide). These include LiMn2O4, IMR, LiNiMnCoO2, NMC, INR, LiMnO2.

2. Lithium-cobalt (Lithium Cobalt Oxide). These are NCR, ICR, LiCoO2 batteries.

3. Lithium iron phosphate (Lithium Iron Phosphate or ferrophosphate). Here you can call LFP, LiFePO4, IFR.

Owners household appliances when it comes time to recharge the battery, they are interested in how to do it right. It is better to use a special device. The charger starts the process at a set voltage of 0.05 V, gradually increasing it to 4.2. The value should not rise higher, because this harms the performance of the battery.

The current strength allowed for charging should fluctuate around 0.5 - 1 A. These indicators directly affect the charge rate. If you do not need to use the battery urgently, it is better not to speed up the charging process.

It will take about 3 hours to fully replenish the product. After this time, the battery automatically disconnects from the device. Thus, you can not worry about overheating of the battery and its damage. If your charger does not have a charge control function, you will have to monitor the process yourself and turn it off when necessary. It is best to listen to experts and purchase multifunctional devices with a controller. So the charging process will be the safest.

Currently, purchasing a charger is not a problem. A large number of devices are available in the assortment of shops and outlets different manufacturers and different price category. Experts advise not to take the price as the basis of choice, but pay special attention to the characteristics.

Types of chargers:

1. Charging with a single socket and a current of no more than 1 A. These are the most inexpensive devices that will help out those users who charge batteries only a few times a year.
2. Charging with two sockets, creates a voltage of up to 4.2 V. These devices have a special indicator that monitors the operating time.
3. Universal chargers used for batteries of different chemistry. They can be used not only for lithium, but also for nickel types.

Cost is also an important factor when choosing a quality battery. Devices of higher cost, as a rule, have relays, controllers and indicators. Those who feel their strength and have certain technical and chemical knowledge can make chargers on their own. In this case, it is important to have knowledge about the functioning electrical circuit and battery settings.

Popular 18650 battery models

Among the many options that are on the market, only a few are in good demand. Such products are distinguished by a long service life and reliability.

Panasonic NCR18650B batteries

Consider the most popular battery models and their main characteristics:

• Panasonic NCR18650B - has a capacity of 3400mah. Until recently, this battery held a leading position in terms of volume among other lithium types that are commercially available. The advent of medium-current and higher-capacity batteries has displaced Panasonic from the top spot. However, even now there are buyers for this product. As for the design of this battery, inside it there is an anode twisted into a roll, as well as a cathode. Between them, the manufacturer has placed a separator. All these elements are placed in a cylinder-shaped case.
• Samsung INR18650-25R. The cell capacity is 2500mah. This battery is designed to work with high current. If the load is continuous, then the current strength is 20 A, but if it is periodic, then the indicator increases to 100 A. This battery is perfect for an electronic cigarette. Manufacturers recommend using Samsung INR18650-25R batteries in devices that have a built-in protection system, since they themselves do not have this function. Such products are not suitable for flashlights, as they can be excessively discharged, which is unfavorable for them.

Battery Samsung INR18650-25R

• LG 18650 HE2, 2500 mAh capacity. This battery is high current. With its capacity, it can withstand a load of 8 C and provides a current of 20 A. Due to such characteristics and performance indicators, the battery model is popular and in demand. In addition, the battery also has a lot of advantages. The most important advanced indicator of the device is the latest chemical composition. It is called NCR or Hybrid IMR. This name speaks for itself: it is a hybrid of ICR and IMR batteries. The battery has a cobalt cathode and a coating of manganese and nickel. Through the use of such advanced technology, the battery is discharged to a low voltage, while not losing its operational properties.
• Samsung ICR18650 2600 mAh 26H. Such a battery has an industrial purpose and is characterized by the absence of a protection board. The battery has a high capacity, so it is often used for screwdrivers, laptops and other household appliances. Samsung is often found in repackaging companies that use them to work their products. An acceptable price and a real big one made them the best sellers among 18650 lithium-ion batteries. The positive battery contact is slightly recessed.

Samsung ICR18650 battery

• KeepPower, 3500mah capacity. Another high-quality 18650 battery. The Japanese manufacturer used a board to create such a product, designed to protect the battery from short circuits and overcharging. The maximum current strength is 5 A, the voltage is 3.7 V.

It is quite realistic to charge batteries without harm to them and to maintain their operational properties in the future, knowing the characteristics and allowable voltage and current indicators. The battery will last longer if you take good care of it.

Reading time:

An increasing place in everyday life is occupied by various wireless devices: portable and easy-to-use cordless drills; laptops that allow you to work for a long time without using the electrical network.

All this makes our daily life more convenient and easier.

But a special place is occupied by the use of autonomous battery devices not near the house, where you can always put the device on charge, but far from power sources.

On a camping trip, hunting or fishing, the most necessary, and sometimes indispensable electrical device is a flashlight. Modern flashlights equipped with LEDs have a huge number of advantages.

But the main characteristic of any electric lamp, of course, is the duration of its operation. For tourists who go on multi-day trips, it is the duration of the lamp that is of great importance when choosing.

And this characteristic directly depends on the type of battery that comes with the flashlight.

A big role for any tourist is played by the compactness and lightness of the equipment. Therefore, an important characteristic for batteries are size and weight - the smaller, the better.

At the same time, the batteries must have a large capacity, which will ensure long and uninterrupted operation of the flashlight, often the main source of light in the dark.

Modern technologies make it possible to combine small size and weight with a large battery capacity.

One of the most common batteries for LED flashlights are 18650 batteries. These compact batteries with a relatively large capacity are best suited for modern light sources often used by tourists, fishermen and hunters.

Key features of 18650 batteries

The name itself indicates the dimensions of the battery - 18 millimeters in diameter, 65 millimeters in length. Despite the fact that outwardly they look like AA batteries familiar to many (the so-called "finger" batteries), 18650 batteries are larger in size.

In addition, a distinctive feature of 18650 batteries is the voltage, which is 3.7 V at the output, versus 1.5 V for smaller batteries. The capacity of 18650 batteries varies from 1600 to 3600 mAh. In this case, it is necessary to pay attention to the fact that the capacity of a high-quality battery cannot exceed 3600 mAh.

Batteries can be used in flashlights both one by one and in the Power Bank system - a device that combines several identical batteries.

One of the main qualities and advantages of batteries is the absence of the memory effect and the extremely low level of self-discharge.

18650 batteries can withstand up to 1000 charge / discharge cycles, which is a very good indicator for portable batteries.

Gradually, the battery charge resource decreases, but with the help of special technical devices capacity can be restored, the only condition for restoration is the absence of mechanical damage to the battery.

• It should be borne in mind that for a more rational use of the battery life, you should not discharge it completely.
• It is optimal to recharge the battery when the capacity drops to 40% of the nominal value. If used correctly, the battery will serve reliably for a long time.

To charge 18650 batteries, you will need a special charger that is suitable for all types of batteries of this size. For example, ARE-X1 Fenix ​​charger, i1 NiteCore charger or SmartCharger Pro Robiton charger.

Types of 18650 batteries

The batteries themselves, with a general similarity in technical characteristics, have a different content, according to the type of cathode material. Despite the fact that they all have the designation lithium-ion batteries, there are three types:

• 1) lithium-cobalt (LiCoO2) - the most common batteries, characterized by the highest capacity among lithium-ion batteries;
• 2) lithium-manganese (LiMnO2, LiMn2O4, LiNiMnCoO2) - better known as high-current batteries (INR), capable of delivering currents of 5-7C to the load, but usually inferior in capacity to lithium-cobalt;
• 3) lithium-ferrophosphate (LiFePO4) batteries - in all respects they undoubtedly outperform the first two types, except for the operating voltage and capacity.

Each of these types has its own advantages and disadvantages and is designed to solve specific problems. They differ mainly in capacity and discharge rate.

When choosing a 18650 battery in a store, all information about it, as a rule, can be read on the battery case. The most responsible manufacturers always label batteries.

Therefore, the presence of technical characteristics on the case is a kind of indicator of the quality of the product. Universal or unified system marking does not exist.

However, the following principle is most commonly used.

In labeling, different combinations, latin letters are used. For example: the letter I - indicates that the battery is lithium-ion, with all the characteristics inherent in such batteries.

The letter R - means that you have a battery in your hands that can be recharged if necessary. The letters C/M/F denote the cathode material - cobalt, manganese or iron phosphate, respectively.

Letter combinations can be arbitrary, but at the same time, the size 18650 (length and diameter) and the capacity in ampere-hours are always indicated - from 1000 to 3600.

Rules for the use of 18650 batteries

With numerous advantages, 18650 batteries have one drawback associated with their design. Batteries often fail quickly if overcharged or overheated.

1. Overcharging causes the battery to heat up, causing the battery to catch fire or explode.
2. Manufacturers have provided an option to protect batteries from overheating.
3. When using 18650 batteries in a Power Bank, when connected in series, an electronic board is installed in the circuit, which limits the charge of the entire device to a given capacity.
4. For 18650 batteries, used, for example, in flashlights, an individual system is used to protect against overcharging and subsequent overheating.

The protection is a small electronic protection board that is installed on the negative terminal of an unprotected lithium-ion battery and welded with steel tape to the case.

This prevents not only overheating, but also a short circuit, which can damage not only the battery, but also the charger. The whole structure is packed in thermal film.

Protected and unprotected 18650 batteries also have their own markings, for example: protected, with protected PCB, protection circuit - on protected batteries, unprotected - on unprotected ones.

It is necessary to pay attention to the fact that large manufacturers do not produce protected batteries, but protection is installed by firms that are engaged in their refinement.

Thus, protected batteries are produced under various brands, the number of which is very large.

It should be noted that after installing the protection, the length of the 18650 battery increases by about 3-4 mm, which can cause its own difficulties. Often, a battery of a longer length is not included in a regular place both in a flashlight and in a charger.

It should be borne in mind that the contact spring of the flashlight or charger presses on the battery of increased length with greater force, and this can lead to the negative contact being pressed through and the battery breaking.

Therefore, when buying an 18650 battery, you need to check if they fit your flashlight or charger. However, there are also flashlights and chargers, the manufacturers of which immediately provide for an increased battery size.

In this case, there are no problems with installation and operation, but unprotected batteries for such devices will not work.

Batteries with protection can be used in any devices powered by lithium-ion power sources that do not have a built-in charge-discharge controller.

• It is possible, of course, to use unprotected batteries, but in this case, control of the charge level during recharging is required.
• A special place in the operation of 18650 batteries is their proper storage.
• Batteries should be stored in a case or box and not come into contact with metal products during storage.
• The optimum storage temperature is from +5 to +15 degrees Celsius. Proper storage will increase the life of your batteries, but continuous operation is the best guarantee of longevity.

Lithium-ion batteries gradually lose their capacity and, accordingly, their resource during long-term storage.

Devices powered by 18650 batteries

18650 batteries are widely used in everyday life.

1. Currently, one of the most common devices powered by 18650 batteries are powerful LED lights.
2. It is these batteries that can provide power to powerful LEDs.
3. High battery capacity allows the flashlight to work for a long time without recharging. This is especially important on long hikes. For an LED flashlight, you will need a battery equipped with a protective board.
4. When using an unprotected battery, constant monitoring of its operation is necessary.

Another large group of devices in which these batteries are used are hand-held cordless drills, which are called screwdrivers for short.

These essential construction and repair tools are often bundled with 18650 batteries bundled into a Power Bank. The undoubted advantage of such batteries is a high starting current, which allows the tool to work with a high power load.

The large capacity of the batteries allows continuous use of the tool for several hours. In the event that the battery begins to discharge, it can be safely put on recharging without fear of the memory effect inherent in other types of batteries.

18650 batteries are the most best option for a screwdriver due to small dimensions, high capacity and relative speed of charge.

• 18650 batteries are used in laptop batteries, also combined in Power Bank. They allow these irreplaceable gadgets to work autonomously for several hours.
• Given the rather high consumption of electrical energy by a laptop, batteries are used during operation, which together give a large capacity.
• Another plus is that the battery can also be recharged when working with a laptop from the mains, the only thing to consider is that the mains power must be turned off as soon as the charge indicator on the laptop shows that the batteries are charged.
• Otherwise, the battery life will gradually decrease. Batteries supplied with laptops are often subject to recovery, as they are well protected by the laptop case and, as a rule, do not have mechanical damage.

It should be noted that only unprotected batteries are used in laptop and screwdriver batteries, this must be taken into account when restoring, repairing or replacing them.

So, let's sum up. A large number of modern high-power LED flashlights use 18650 batteries as a power source. Lightweight and compact, these batteries have enough capacity to ensure a long run of the flashlight and other devices.

Manufacturers are trying to improve the design of batteries as much as possible, and manufacturers of devices powered by batteries, in turn, optimize their products for long-term work with such batteries, both with protection against overheating and without protection.

We hope that this article will help in choosing high-quality and reliable 18650 batteries - necessary for the autonomous operation of various devices both at home and on a camping trip, hunting or fishing.

Advantages and disadvantages

I will say right away that Li-ion (lithium - ion, lithium) 18650 batteries at 3.7v, like many other things, I buy on AliExpress. Links to them are at the bottom of the article.

Why there? Because on AliExpress has a very large selection and you can buy them at a very affordable price..

But, precisely because 18650 batteries are very popular, the Chinese are very fond of forging them, so you should not immediately throw yourself at beautiful numbers with an unrealistically large capacity or at a low price.

I will talk very briefly about the batteries themselves, give some advice - which batteries are better not to buy, how to use them and give links to really good 18650 batteries, and which ones are better - you decide, because. and their characteristics and purpose are different, although the average operating voltage is the same for all - 3.7v.

Usually, battery size 18650 is: diameter - 18-18.3 mm, height - 65 mm (for batteries without protection). Protected batteries have a diameter of about 18.5 mm and a height of up to 70 mm.

A protected battery, unlike an unprotected one, has a board built into it (charge / discharge controller), and it externally has a positive contact like a small (about 1 mm) protruding pimp.

This controller protects the battery from overcharging above 4.2v and from discharging below 2.75-3.0V (for different batteries, the lower value is different, you should look at its description (datasheet), because outside these values, the battery will quickly fail.

Which one is better to use? It depends on how you charge it and where you use it ...

As a rule, normal chargers (designed specifically for charging lithium-ion batteries, such as the 18650 type) have a charge controller and do not recharge these batteries, so any type can be used in them.

PowerBanks have a full charge and discharge controller, so they use batteries without protection, and in some cases, protected batteries will not even fit into the PowerBank due to the protruding contact.

But if you use a battery, for example, in a simple Chinese lantern, a children's typewriter or an electronic cigarette, where there is no built-in discharge controller, then you must definitely use a battery with built-in protection, otherwise it will not last long.

By the way, about electronic cigarettes, mechanical mods and so on. - it is better to use them high current lithium 18650 batteries, designed for the return of high currents - up to 40-60 A(briefly).

1. Ordinary batteries, designed for loads of 2-3C (up to 4-5A), will also quickly “die”.
2. If you are using a battery with a boost converter, then pay attention - at what minimum input voltage does this converter work?
3. If from 3 volts, then everything is fine, you can use any type, but if, for example, from 2 volts, then the battery without built-in protection will be “sucked out” completely, which is “no buzzing”.

Regarding the capacity of 18650 type batteries: at the time of this writing (early 2017), the maximum capacity that I had to deal with was a maximum of 3400 mAh, and only from well-known manufacturers such as Sanyo, Panasonic, most others, such as LG, Sony, Samsung, etc. - about 3000 mAh, and the price for them is also not the lowest.

Personally, I currently prefer time-tested 2600 mAh batteries from Sanyo and Samsung, which you can already buy at a very affordable price.

But, on AliExpress you can buy a lot of cheap fakes like Ultrafire, on the cases of which the capacity of 3000, and 5400, and even 9000 mAh, etc. can be indicated, but the real capacity of which will be 5 or even 10 times lower!

In addition, if you have an 18650 battery, and there is nothing to check its real capacity, then just weigh it! Batteries with a capacity of 2000 mAh or more must weigh at least 40 grams! And, as a rule, the higher the real capacity, the more it will weigh ...

Although some "left" manufacturers have already learned to "bypass" this moment. They just add something inside for weight, like normal sand.

That's why, do not chase after a low price and large numbers on the case, do not save on this!

The most reliable is to use trusted links, but at the same time, always, without fail, carefully read the reviews for a particular battery anyway, and then you will not fall into a “slump”.

18650 battery specifications

Most small household appliances are powered by rechargeable batteries. The most widely used is the 18650 battery. If you need a battery for a flashlight or for an electronic cigarette, most likely you will need the 18650 variety - Sanyo, for example.

General information

The standard size of 18650 batteries is the most common in the domestic and foreign markets. They belong to Li-Ion batteries.

There are three classes of lithium-ion batteries:

• LiCoO2 or lithium-cobalt;
• high-current lithium-manganese LiMnO2, LiMn2O4 and LiNiMnCoO2;
• LiFePO4 - lithium ferrophosphate.

Each type has its own advantages and disadvantages and is designed to perform specific tasks. LiCoO2 were once the most common, they have the highest capacity among other lithium-ion batteries.

High-current ones are inferior in capacity to lithium-cobalt ones. LiFePO4 are good in all respects, but underestimated by the market. All lithium batteries have the ability to hold a charge for a long time.

Consider how to decipher the digital designation 18650:

• first two digits ( 18 ) – diameter;
• next pair of digits ( 65 ) – length;
• the last digit () indicates the shape of the battery, in this case - cylinder.

Each battery manufacturer has its own specific marking.

Consider our own notation with examples:

• Panasonic NCR18650B- a kind of cobalt chemistry, in simple words - these are class II batteries, but without the use of Mn;
• Sanyo NCR18650 BF- in this case, the marking "BF" can mean chemistry, type and capacity.

Where applicable

This type of battery is widely used in LED flashlights, Power Banks, laptop batteries, screwdrivers, portable telephone handsets, electronic cigarettes, and even electric bicycles.

How to charge

Charging 18650 batteries must be regular, otherwise there is a risk that the battery will fail prematurely. It is also important to follow the basic rules for charging lithium-ion batteries.

How to charge this box:

• Charging starts with a voltage of 0.05 V, and ends when U rises to 4.2 V. This valid parameters, the safest for batteries.
• You can charge the battery at a charge current of 0.5 A and 1 A. 0.5 A is the optimal indicator, and at 1 A the charging process will proceed faster. It is not recommended to speed up the process without special need.
• Charging time should not exceed three hours otherwise there is a high risk of damage to the chemical structure of the battery. An exception may be those situations where the device has a control system. In this case, it itself determines the charging time.
• It is highly undesirable to allow a deep discharge of 18650. In this case, it is very difficult to restore the previous parameters of the product. It is much easier for the owner to periodically recharge the device for a short period of time.

The sales assistant will tell you how long it takes to charge the device. It depends on the capacity of the battery and its initial condition.

Chargers

Today, buying a charger is not a problem. There are many devices on sale at different prices, but the choice of charger is not only based on the budget. You should also pay attention to the types of devices.

• The single socket charger has a current level of 1 amp. Often this is the most budget option. It is suitable for those who do not have to charge batteries more than a few times a year.
• The charger with two sockets is used for cells with a voltage level up to 4.2 V. Higher voltage levels will damage the battery. Typically, such devices are equipped with an indicator that controls the charging time.
• There are also universal devices, with which you can charge not only lithium batteries, but also nickel-cadmium batteries, as well as boxes from several devices.

The quality of the charger depends on its cost. More expensive devices have indicators, relays.

Those who have the desire and the ability can do the charging for lithium-ion batteries with their own hands. To do this, you need to know the parameters of battery charging, as well as the principle of operation of the electrical circuit.

Consider the simplest way, which even a schoolboy can handle. We will replace the professional charger with an old charger from Nokia or Samsung.

The wires are released from the sheath, disconnected into plus and minus (the positive wire is usually red, and the negative wire is black). A battery is attached to the bare wires. You can do this with plasticine. The element is connected to a computer or network, observing the polarity.

It is advisable to follow the process. It will take about an hour to charge the battery this way.

Knowing the basic properties and indicators of current and voltage, it is easy to carry out the charging process without harm to the battery. Careful attitude will allow the product to last as long and efficiently as possible.

Types and marking of lithium-ion batteries 18650

We received a lot of questions by mail from readers about 18650 lithium-ion batteries. Therefore, it was decided to write a small FAQ on this type of lithium batteries. 18650 battery cells are in demand in today's market.

They are used in laptop batteries, various flashlights, power bank, some types of power tools. In this note, we will consider the main questions that people are most interested in.

Namely, the varieties of 18650 elements, issues related to their marking, protection, pros, cons and price.

Varieties of 18650 batteries

To begin with, it is worth mentioning the main types of 18650 batteries, which differ in the cathode material. This largely determines such properties of batteries as capacity and the maximum allowable discharge current.

• LiCoO2 (lithium-cobalt). These batteries are the most common and have the largest capacity values ​​​​among models made using Li─Ion technology;
• LiMnO2 or LiMn2O4 or LiNiMnCoO2 (lithium-manganese group). In terms of their capacity, they lose to the first group, but they have a high discharge current (5-7 * C);
• LiFePO4 (lithium-ferrophosphate). These battery cells surpass the previous ones in most parameters, but are inferior in capacity and voltage. They have a service life of up to 1,000 charge-discharge cycles and charge in less than 1 hour.

Now, in general, about 18650 batteries. These are cylindrical elements in their shape resembling AA (“finger”) and AAA (“little finger”) batteries. But in size 18650 exceed them. The length is 66.5, the diameter is 18 millimeters. For comparison, in fingernails, these values ​​\u200b\u200bare equal to 50 and 14 mm.

The output voltage of the 18650 battery is 3.78 volts. The capacity of the most common batteries lies in the range of 2000-3200 mAh. Less common are banks with a capacity of 1000, 1100, 1500 mAh.

How to decipher the marking of 18650 batteries?

Let's analyze the marking of 18650 lithium-ion cells using the following example: ICR18650-26F M.

The first letter I indicates that the battery is made using lithium ion technology. The second letter indicates the material of the cathode. In our case, cobalt. There are the following options:

• C is cobalt;
• M is manganese;
• F ─ iron phosphate.

Form Factor Explanation

And at the end of the marking is the designation of the capacity. In this example, the capacity is 2600 mAh. But usually the ending of the marking is very different depending on the manufacturer. Here, almost everyone can have their own version.

18650 battery protection

According to safety requirements, the voltage of 18650 lithium-ion batteries should be in the range of 2.5-4.2 volts during operation. To meet this requirement, some 18650 batteries are protected. It is a small printed circuit board.

This board is soldered to the element leads using steel or aluminum tape. As a rule, large manufacturers do not produce such protected elements in mass production. They produce unprotected elements that are used in devices with charge-discharge controllers.

• An example is a laptop battery or a screwdriver.
• As a rule, protected lithium-ion 18650 cells are made in small batches in China.
• A protection board is soldered to an unprotected battery, and the whole structure is wrapped in a thermal protective film. When buying such an element, you need to consider that its length will be slightly longer (1.5-2 mm).
• It should be borne in mind that the installation of protection on lithium-ion 18650 increases the length of the element. And when there are several of them, then this increase is summed up.

As a result, a set of such elements may simply not fit into the body of the flashlight or interfere with the closing of the cover, which is usually the negative contact.

It must be remembered that protecting the 18650 cell will not protect the device and batteries from overheating. Its role is to control tension. Many use 18650 batteries in flashlights without protection. It is relatively safe to do this if you have 1 element in your lamp. When several elements are installed, they must be protected.

Pros, cons, price

The advantages of 18650 cells include everything that is inherent in other lithium-ion batteries:

• Large energy intensity;
• Small self-discharge;
• No "memory effect";
• Small dimensions and weight.

The disadvantages include:

• 18650 sensitivity to overcharge and overheat. The problem is partially solved by installing a protection scheme;
• These batteries require more care than other types of batteries. In particular, this applies to storage. They need to be stored at 40-50% charge at a temperature of 5-15 degrees Celsius;
• Aging (degradation) of lithium-ion goes from the moment of their release. Even if they are not used.

The spread at 18650 on the market is quite large. We can say the following with certainty. On Aliexpress, the average price of 4 18650 cells with a capacity of 2600 mAh (without protection) is kept at around 600-700 rubles.

1. In Russian online stores, one battery cell (with protection) can cost 600 rubles.
2. Therefore, even taking into account the risk of low-quality goods from Uncle Liao, it is more profitable to order in China.
3. In addition, recently lithium batteries have been made of normal quality there.
4. If the article was useful to you, share the link to it in in social networks. This will help the development of our site.
5. Vote in the poll below and rate the material! You can leave corrections and additions to the article in the comments.

18650 Li-ion batteries (lithium)

18650 batteries(sometimes referred to as 168A) is one of the most common sizes used in professional LED flashlights.

At lithium-ion batteries form factor 18650 has the highest capacity/size ratio. They are cylindrical in shape, 18 mm in diameter and 65 mm long. Capacity Li-ion batteries 18650 3.

7V from different manufacturers is 2200 - 3400 mAh. Panasonic 18650B 3400 mAh has the largest capacity of existing batteries.

Brief description of Li-ion batteries.

Lithium-ion battery (Li-ion) This is the most widely used type of battery. They are used in devices such as laptops (by the way, laptop batteries most often use 18650 batteries connected in series.

Replacing native batteries in a laptop with Panasonic NCR18650B 3400mAh batteries will help restore the "dead" native laptop battery, as well as more than double the battery life), phones, electric cars, camcorders, radio stations and digital cameras.

And of course, Li-ion batteries are actively used in LED lights for various purposes. The first Li-ion battery was released by Sony Corporation in 1991.

Currently, the best Li-ion batteries in terms of key characteristics (real capacity and level of voltage sag under load) are Panasonic.

In our online store you can buy Li-ion batteries for both LED lights and other equipment.

Characteristics of Li-ion batteries.

Depending on the electrochemical scheme Li-ion batteries 18650 show the following characteristics:

• In a charged state, the voltage is 4.2 V, in a discharged state, 2.5 V
• Energy density: 110 - 250 Wh/kg.
• Internal resistance: 5 - 15 mOhm/1Ah.
• The number of charge / discharge cycles before the loss of 20% capacity: 1000 - 5000.
• The maximum allowable current in the charger is calculated on average as follows: the battery capacity must be divided by 3. For example, take a Panasonic 3100 mAh battery.
• It is necessary 3100/3=1033 mAh (this will be the maximum charging current, from which the battery does not deteriorate). With a higher charging current, the battery will charge faster, but will withstand fewer charge / discharge cycles.

Self-discharge at room temperature: 3% per month. Operating temperature range: -10 +60 °C (batteries cannot be charged at sub-zero temperatures). 18650 stands for: 18 mm diameter and 65 mm length.

• High capacity.
• Low self-discharge.
• No memory effect. The memory effect is an irreversible loss of battery capacity when recharging an incompletely discharged battery.
• In other words, Li-ion batteries do not need to be completely discharged before charging, unlike some other types of batteries.
• Maintenance free.

In modern professional LED flashlights, an electronic circuit (driver) is used to control the LED.

If you want to buy accumulators (lithium-ion or nickel metal hydride) for use in LED flashlights, you need to consider the recommendations of the flashlight manufacturer, which batteries are best suited for it.

When choosing batteries, in addition to capacity, it is necessary to take into account security and some other parameters. Carefully read the documentation for the flashlight, if necessary, contact us for advice.

TO batteries Of course you need a charger. In our store you can buy chargers for Li-ion batteries, Ni-MH batteries and batteries other types that are used in LED lights.

Even a good thing can be ruined. This fully applies to batteries (in this case, a bad “protection board”).

As mentioned earlier, the protection board saves the battery from overcharging, overdischarging, short circuit. It is worth paying special attention to its quality. Because

being a link between the source of consumption and the battery, it can become a bottleneck and not reveal the full potential of the battery (the characteristics of the battery will be limited by it).

In addition, the protection board itself consumes power to a greater or lesser extent depending on the quality.

It will be most clear if I immediately start with an example.

Panasonic 3400 mah batteries are the most common batteries at the moment. Their cost can be 800 rubles, and 500 rubles.

What's the catch? That's right, in defense (for most cases, this statement is true.

But there may be other nuances regarding rejected due to a discrepancy in capacity, used / used, expired and even fake batteries. This will not be considered here.) There are several types of protection boards.

From left to right: very bad, good, very good 🙂

1. In the first option, only 1 mosfet is installed, the simplest voltage controller. In general, in addition to the terrible workmanship, such protection is not safe for the flashlight itself (it can burn out from the load and close the battery, from which it will explode. By the way, the flashlight breaks the battery into fragments). And yet - this protection does not hold high currents, it will turn off early when the battery is only half discharged. Thus, the operating time of the flashlight will be 2 times less. This applies only to the MAXIMUM mode of the flashlight. In weak modes, the battery will work as expected.
2. The second protection is normal, holds current up to 4-5 Amps, which is quite enough for most flashlights. It doesn't get hot and is very reliable.
3. The third option uses as many as three mosfets. This gives: an operating current of up to 7.5A (the full potential of the battery in terms of current output is revealed), low consumption (it will be possible to squeeze more capacity out of the battery), clarity of operation at critical currents / voltages. These protection boards are installed on our batteries!

Device and alteration

Lithium-ion batteries have entered our lives along with cell phones and mobile devices. Until recently, lithium-ion batteries were practically not used in everyday life for other autonomous devices, the main power source for such devices is nickel-metal hydride batteries of the sizes AAA, AA, C, D that are familiar to us.

Now they are gradually being replaced by lithium-based batteries, as their advantages in operation have become undeniable.

• Very low self-discharge. Energy losses are minimal when used correctly.
• High energy density, correspondingly higher energy capacity without increasing the size compared to similar nickel-based batteries.
• Higher output voltage. In comparison, the minimum for lithium is 3.6 Volts with a standard nickel of 1.2 Volts for the same size.
• Reducing the mass of the battery while maintaining the dimensions.
• Increased number of discharge-charge cycles while maintaining performance.
• A slight decrease in performance with a loss of energy intensity after numerous discharge-charge cycles.

Given these advantages, all more of professional users is converting its stand-alone devices to cylindrical lithium-ion batteries and assemblies from them. At the same time, not everyone knows how to properly use, maintain, store new power sources. And also pick them up by size and current parameters.

The size designation of cylindrical lithium-ion batteries is different from the usual for all nickel ones - it is digital, for example, 14500 or 18650.

Such coding is unusual, but at the same time it is convenient for selecting the required battery according to the size of the slot of the electronic device.

The first two digits of the code indicate the diameter of the battery in millimeters, the second - its height. For example, size 18650: 18mm diameter, 65mm height.

Rules for the use of lithium-ion batteries and assemblies

Lithium-ion batteries are both reliable and capricious, which at first glance seems like a paradox. They are whimsical in storage, maintenance and operation. If the conditions of use are violated, they fail very quickly. But subject to all the rules, they serve for a long time with high performance.

Main restrictions:

• The minimum voltage for lithium-ion batteries should not be less than 2.2-2.5 volts.
• The maximum voltage for lithium-ion batteries should not exceed 4.25-4.35 volts.
• Lithium-ion batteries work well in sub-zero temperatures, but you can’t charge them in the cold, especially if the temperature is below zero degrees.
• The charge current of lithium-ion batteries should not exceed half of their capacity. For example, for a 2000mAh battery, the maximum charge current should be 900-1000mA.
• The discharge current (working) should not be higher than 2 times the value of the battery capacity. For example, for a 2000mAh battery, the maximum discharge current is 4000mA.
• The exceptions are high-power lithium-ion batteries, the discharge current of which can exceed their energy capacity by 5-10 times. Such batteries are marked with the corresponding inscription.

Cylindrical lithium-ion batteries are often used for large battery packs. Battery assemblies have higher power and a long cycle life. Such battery assemblies are used in high power devices. This is what the lithium-ion battery of a powerful screwdriver or drill looks like.

When assembling the battery yourself, you should remember that lithium-ion batteries do not tolerate overheating, so DO NOT SOLDER them! Such a battery assembly will not work, since it can be said with certainty that the soldering of the contacts disabled the batteries.

When assembling the battery, a special welding tape and contact welding are used.

For safe operation of the battery, a charge-discharge controller is required.

When assembling batteries, only unprotected lithium-ion batteries are used! Using them, you can assemble a large, very energy-intensive battery (battery), which can be used in powerful electrical appliances, serve as an additional power source.

Such batteries are found in electric drills, screwdrivers, spotlights, photo and video equipment, laptops, monitors, etc. with the obligatory addition of protection against overvoltage, overheating and short circuit in the form of a controller board.

Protected or unprotected lithium-ion batteries

What are the differences and which one to choose? - the main question of concern ordinary user. The answer is in the name: protected ones have their own overheat and overvoltage protection board and do not need an additional charge-discharge controller.

If you want to build your own lithium-ion battery or replace the battery in a ready-made battery for an electrical device (such as a screwdriver), you need an unprotected lithium-ion battery.

In other cases - when replacing the original batteries of devices or transferring them from nickel-metal hydride to lithium - you need to buy a protected lithium-ion battery.

If you open the shell of a protected lithium-ion battery, then under it we will find an ordinary unprotected battery with the same parameters as indicated on the outer shell.

The main difference between a protected battery and an unprotected one is an electronic protection board welded to one of the contacts.

The protection board with welding tape is welded to one of the contacts of an unprotected lithium-ion battery.

Then everything is packed in a film with the marking of the manufacturer of protected batteries. Conscientious manufacturers indicate on the outer packaging the manufacturer of the used unprotected battery and the parameters in accordance with the marking of the unprotected battery.

• There is one very important point to keep in mind when choosing a protected battery for your device. Due to the welded protection board and film packaging, the size of the battery becomes slightly larger than the declared, original size of the unprotected battery.
• Height increases by 3-5mm.
• The diameter becomes larger by about 0.5 mm.

When choosing a protected battery, you should ask the manufacturer of the unprotected one. Unfortunately, not all manufacturers indicate it on the packaging, although they often use unprotected batteries not of their own production.

For example, they weld protection and pack unprotected batteries of well-known brands Panasonic, Sony, Samsung and others. You should not buy protected batteries if they do not indicate all the parameters of the "stuffing": energy intensity, voltage, protection board.

It is worth checking the protected batteries by touch - if the protection board on the positive contact does not move when pressed, it must be welded.

Cylindrical lithium-ion batteries can only be charged with special chargers. In connection with the popularization of lithium-ion batteries, the range of chargers for Li-Ion is growing.

When choosing a charger, it is necessary to pay attention to its charge-discharge parameters, the size of the slots and correlate them with the lithium-ion batteries used for proper operation and maintaining performance.

18650

Li-ion batteries Li-ion Olight, Xtar, Panasonic, LG, Samsung, Sanyo, Soshine, size 18650 with a voltage of 3.7 V.

A lithium-ion battery consists of electrodes (cathode material on aluminum foil and anode material on copper foil) separated by electrolyte-impregnated porous separators.

The package of electrodes is placed in a sealed case, the so-called jar, the cathodes and anodes are connected to the current collector terminals - plus and minus of the battery.

The body has a safety valve that relieves internal pressure in emergency situations and violation of operating conditions.

Lithium-ion batteries differ in the type of cathode material used. The charge carrier in a lithium-ion battery is a positively charged lithium ion, which has the ability to intrude into the crystal lattice of other materials, such as graphite, to form a chemical bond.

Batteries are extremely sensitive to overvoltage during charging, which can cause the battery to catch fire.

Therefore, in our online store we sell only protected rechargeable batteries, in the body of which a special electronic external / internal voltage control board is built - a protection chip that protects the battery from exceeding the charge voltage - overcharging and from deep discharge, at which the voltage on the battery bank drops below the threshold of 2.75 volts and the battery fails .

A feature of Li-ion is that a battery with a voltage close to zero can hardly be charged. Also, this board can optionally monitor the temperature of the battery, turning it off in case of overheating, limiting the depth of discharge and the current consumption.

But do not be afraid that the working volume of stored energy remains unused, because the discharge area from the upper limit of 4.2 V to 2.75 V makes up 90-95% of the entire battery capacity.

The operating time and the number of life cycles of Li-ion batteries depend primarily on the charger used.

High smart chargers will not allow overcharging and undercharging of your Li-ion batteries, will automatically turn off when the charging cycle is completed or the temperature is exceeded, which may not be safe.

The smart charger uses a charge profile direct current (CC) and a constant voltage charge ( CV), this charge charging method is the recommended and fastest, preserves their resource and does not reduce their capacity of your Li-ion batteries over time, at which they serve their full service life.

Smooth start charge ( TC) to prevent damage to the battery when charging with high current. A wide range of charging currents from 0.25 to 2 Amp for charging li-ion batteries with a wide range of capacities.

Ask yourself: “Where can I buy cheap 18650 batteries in Moscow?” In the assortment of the online store Fonarik4you.

Common crawl en You can always find and buy almost any type of batteries and intelligent chargers for them, as well as order a charger by cash on delivery by Russian Post to any region of Russia.

Batteries are used in the automotive industry and in the repair of chiller air conditioners.

AAA AA/14500CR123A/16340 18650 26650/32650 Olight/Fenix/MagicShine

How to choose a battery

18650 batteries belong to a large range of lithium-ion (Li-ion), which are widely used as power sources in many modern electronic devices: mobile phones, mp3 players, flashlights, laptops, etc.

The big advantage of lithium-ion batteries over conventional batteries, which are often called "dry" batteries, is that batteries, unlike batteries, are rechargeable cells, which means they will last much longer.

In general, today lithium-ion batteries have the best performance among all power sources, only relatively high cost can be noted among the shortcomings.

In order for the cost of batteries not to hit the buyer on the wallet, you can buy inexpensive 18650 batteries from us.

1. The operating voltage of the lithium-ion battery is from 2.75 to 4.2V. It should be noted that "lithium-ion" really does not like deep discharge, if the cell voltage drops below 2.5V, this negatively affects the battery capacity, to the point that it can fail.
2. The upper voltage bar of 4.2V should also not be exceeded, ignoring this rule can cost even more serious consequences, in addition to destroying the battery, exceeding the voltage is fraught with an explosion of the battery.
3. Therefore, it is very important to use the so-called "smart chargers" designed specifically for charging Li-ion. Such charging will not supply a voltage higher than 4.2V, and will also reduce the current strength as the battery voltage increases.
4. The capacity of lithium-ion batteries per unit mass sets an absolute record; no other batteries are capable of holding such a charge at a predetermined mass.

Recently, 18650 lithium-ion batteries have been very popular. These batteries are similar to ordinary AA batteries, but a little larger.

Almost all powerful flashlights and power banks (power banks) use exactly 18650 batteries. Another 18650 is used in power tools independent of the mains: screwdrivers, soldering irons, drills.

Many children's toys (remote control cars, toy aircraft, etc.) also use batteries of this size.

It is worth beingware of fakes, at the moment, 18650 batteries have the largest capacity of 3400 mAh. If the manufacturer claims the capacity of the 18650 battery is higher than 4000 mAh, you can be sure that this is a hoax.

Many Chinese batteries are famous for this cunning, on the stickers of which there are inscriptions 4200, 4400, 4800 and even more than 5000 mAh. Many heroes should be known by sight, so as not to accidentally purchase such a battery.

For example, the Bailong company reports 4200 mAh, while the real test shows from 600 to 800 mAh. UltraFire, TrustFire - about the same kind of batteries.

Good batteries are made by manufacturers such as: Sanyo, Samsung, LG, Panasonic, CJ. Their capacity is usually from 2200 to 2600 mAh, but the main thing is that the capacity is honest.

If you didn’t take my word for it, I suggest you do an experiment yourself. Check how long the flashlight will last, say, with an industrial LG and Bailong.

However, there is a more visual test: take a high-quality 18650 battery in one hand, and in the other Chinese fake You will be surprised at their weight difference.

These are 3.5-3.7 volt lithium-ion batteries. They are used in a wide range of electronics, including laptops, digital cameras, flashlights, and even electric bikes and electric cars like the Tesla. There are 2 types of batteries, protected and unprotected, unprotected are ordinary industrial banks that are used in laptops, electric bicycles. Protected batteries are the same banks, only additionally equipped with a board with protection against short circuit and overcharge, the board is installed on one of the contacts, the dimensions of protected batteries will, as a rule, be slightly longer and slightly wider.

The discharge voltage of these batteries should not fall below 3 volts. The rated charging voltage should not exceed 4.2 volts, and the maximum temperature should not exceed 70 degrees. The average life of these batteries is 36 months or 1000 charge cycles, and these batteries age even if they are not used and stored at high temperatures, and a full discharge gradually kills these batteries. The capacity of 18650 batteries should not exceed 3600 mAh, anything above this value is a guaranteed fake and it is better not to buy such a battery.

The battery size is 18650. And what do all these numbers mean?

The first two digits "18" mean the diameter in millimeters. In our case, the width of the battery will be 18 mm (millimeter).

The third and fourth digits (65) indicate the length in millimeters. This will be 65 mm (millimeter).

The last digit zero indicates the shape of the battery, in this case it is cylindrical.

Dimensions with protection 66.5 * 18 mm.

The metric system is almost always used, so the next time you see a li-ion battery with numbers: (18650, 18500, 16340, 16650, 14500, 26650), you will know for sure the meaning of all these numbers.