How to properly charge a lithium-ion battery: instruction manual. Operation of lithium-ion batteries How much lithium is in the battery

Lithium-ion (Li-ion) batteries used in most modern tablets, smartphones and laptops require different maintenance and operation compared to nickel-cadmium (Ni-Cd) and nickel-metal hydride (Ni-MH) batteries used in earlier devices.

In fact, proper care of your lithium-ion battery can increase its lifespan by 15 times compared to misuse. This article will provide tips on how to maximize the life cycle of expensive lithium-ion batteries in all your portable devices.

Just recently, Fred Langa, a journalist for the Internet portal Windows Secrets, had to replace a damaged smartphone - and it was his mistake.

The main symptom did not bode well - the phone case was deformed because the body of the device itself began to bend.

Upon disassembly and detailed examination, it turned out that the smartphone’s battery was swollen.

Initially, Fred did not notice any changes: the battery looked more or less normal when looking at it face-on (Figure 1). However, when the battery was placed on a flat surface, it became obvious that its top and bottom edges were no longer flat and parallel to each other. There was a serious bulge on one side of the battery (Figure 2). This bulge caused the phone to bend and become deformed.

The bulging of the battery indicated a serious problem: the accumulation of toxic gases under high pressure inside the battery.

The battery case did its job perfectly, but the toxic gases made the battery look like a tiny pressure cooker bomb just waiting to detonate.

In Fred's case, both the phone and the battery were damaged - it was time to buy a new smartphone.

The sad thing is that this problem could have been easily prevented. The final part of the article will highlight Fred's mistakes.

To avoid repeating the mistakes of the past with the new smartphone and other lithium-ion devices such as tablets, laptops, Fred began to seriously research the proper operation and maintenance of lithium-ion batteries.

Fred wasn't interested in extending battery life - these techniques are familiar. Most devices offer manual or automatic power-saving modes and methods for adjusting screen brightness, slowing down processor performance, and reducing the number of apps running.

Fred rather focused on battery life extension issues - ways to keep the battery in good working order and extend the battery life to its maximum level.

This article includes a brief thesis statement based on Fred's research. Follow these five tips to ensure your lithium-ion batteries perform well, last, and safely in all your portable devices.

Tip 1: Monitor the temperature and do not overheat the battery

Surprisingly, heat is one of the main enemies of lithium-ion batteries. Causes of battery overheating may include misuse factors, such as the speed and duration of the battery's charging and discharging cycles.

The external physical environment also matters. Simply leaving a device with a lithium-ion battery in the sun or in a closed car can significantly reduce the battery's ability to accept and hold a charge.

The ideal temperature conditions for lithium-ion batteries is a room temperature of 20 degrees Celsius. If the device heats up to 30C, its ability to carry a charge is reduced by 20 percent. If the device is used at 45C, which is easily achievable in the sun or when the device is intensively used by resource-intensive applications, the battery capacity is reduced by about half.

So, if your device or battery becomes noticeably warm during use, try moving to a cooler location. If this is not an option, try to reduce the amount of power your device uses by disabling unnecessary apps, services, and features, lowering the screen brightness, or activating the device's power-saving mode.

If this still doesn't help, turn off the device completely until the temperature returns to normal. For even faster cooling, remove the battery (of course, if the design of the device allows it) - this way the device will cool down faster due to physical separation from the power source.

By the way, although high temperatures are the main problem with lithium-ion batteries, low-temperature operating conditions are not a major concern. Cold temperatures do not cause long-term damage to the battery, although a cold battery will not be able to produce all the power it could potentially produce at its optimal temperature. The drop in power becomes very noticeable at temperatures below 4C. Most consumer-grade lithium-ion batteries essentially become useless at temperatures near or below freezing.

If a device with a lithium-ion power supply becomes excessively cold for any reason, do not attempt to use it. Leave it unplugged and move it to a warm place (pocket or heated room) until the device reaches normal temperature. As with overheating, physically remove the battery and separate heating will speed up the warm-up process. After the battery warms up to normal temperature, its electrolytic properties will be restored.

Tip 2: Unplug the charger to save battery

Recharge - i.e. Connecting the battery to a high voltage source for too long can also reduce the battery's ability to hold a charge, shorten its service life, or what is called “kill it outright.”

Most consumer-grade lithium-ion batteries are designed to operate at a voltage level of 3.6V per cell, but operate at a higher 4.2V when charging. If the charger supplies high voltage for too long, the internal battery may be damaged.

In severe cases, overcharging can lead to what engineers call “catastrophic” consequences. Even in moderate cases, the excess heat generated during recharging will create the negative temperature effect described in the first tip.

High-quality chargers can work in concert with the circuitry of modern lithium-ion batteries, reducing the danger of overcharging by reducing the charging current in proportion to the battery's charge.

These properties vary significantly depending on the type of technology used in the battery. For example, when using nickel-cadmium (Ni-Cd) and nickel-metal hydride (Ni-MH) batteries, try to leave them connected to the charger for as long as possible. This is due to the fact that older types of batteries have a high rate of self-discharge, i.e. they begin to lose a significant amount of stored energy immediately after being disconnected from the charger, even if the portable device itself is turned off.

In fact, a nickel-cadmium battery can lose up to 10 percent of its charge in the first 24 hours after charging. After this period of time, the self-discharge curve begins to level off, but the nickel-cadmium battery continues to lose 10-20 percent per month.

The situation with nickel-metal hydride batteries is even worse. Their self-discharge rate is 30 percent higher than that of their nickel-cadmium counterparts.

However, lithium-ion batteries have a very low self-discharge rate. A good working battery will only lose 5 percent of its charge in the first 24 hours after charging and another 2 percent during the first month after that.

Thus, there is no need to leave the device with a lithium-ion battery connected to the charger until the last moment. For best results and extended battery life, unplug the charger when a full charge is indicated.

New lithium-ion battery devices do not need to be charged extensively before first use (8 to 24 hours of charging is recommended for devices with nickel-cadmium and nickel-metal hydride batteries). Lithium-ion batteries are maximally charged when they indicate 100 percent charge. Extended charging is not necessary.

Not all discharge cycles have the same effect on the condition of the battery. Prolonged and intensive use generates more heat, seriously straining the battery, and shorter, more frequent discharge cycles, on the contrary, extend the battery life.

You might think that increasing small discharge/charge cycles can seriously reduce the life of the power supply. This was only natural for outdated technologies, but does not apply to modern lithium-ion batteries.

Battery specifications can be misleading because... Many manufacturers view the charge cycle as the time required to reach a 100 percent charge level. For example, two charges from 50 to 100 percent are equivalent to one full charge cycle. Likewise, three cycles of 33 percent or 5 cycles of 20 percent are also equivalent to one full cycle.

In short, a large number of small charge-discharge cycles does not reduce the total number of full charge cycles for a lithium battery.

Again, the heat and high load from heavy discharges reduce battery life. Therefore, try to reduce the number of deep discharges to a minimum. Do not allow the battery charge level to drop to values ​​close to zero (when the device turns itself off). Instead, consider the bottom 15 to 20 percent of your battery charge as an emergency reserve—for emergencies only. Get used to replacing the battery if possible, or connecting the device to an external power source before the battery is completely drained.

As you know, fast discharging and fast charging are accompanied by the release of excess heat and negatively affect the battery life.

If you have used the device intensively under high loads, allow the batteries to cool to room temperature before connecting to the charger. The battery will not be able to accept a full charge if it is heated.

While charging the device, monitor the temperature of the battery - it should not overheat too much. A hot battery during charging usually indicates that too much current is flowing quickly.

Overcharging is most likely with cheap, unbranded chargers that use fast charging circuits or with wireless (inductive) chargers.

A cheap charger can be a regular transformer with wires connected to it. Such “silent charges” simply distribute the current and practically do not receive feedback from the device being charged. Overheating and overvoltage are very common when using chargers like this, which slowly destroys the battery.

“Fast” charges are designed to provide a minute charge, not a long hour-long charge. There are different approaches to fast charge technology, and not all of them are compatible with lithium-ion batteries. If the charger and battery are not designed to work together, rapid charging can cause overvoltage and overheating. Generally speaking, it is better not to use a charger from one brand to charge a portable device from another brand.

Wireless (inductive) chargers use a special charging surface to restore the battery's charge. At first glance, this is very convenient, but the fact is that such charges emit excess heat even in normal operation (Some kitchen stoves use induction to heat pots and pans).

Lithium batteries not only suffer from heat, but also waste energy when charging wirelessly. By its nature, the efficiency of an inductive charger is always lower than its conventional counterpart. Here everyone is free to make their own choice, but for Fred, increased heating and lower efficiency are sufficient factors to refuse such devices.

In any case, the safest approach is to use the included charger recommended by the manufacturer. This is the only guaranteed way to keep temperature and voltage within normal limits.

If an OEM charger is not available, use a low output charger to reduce the chance of battery damage due to high power being applied quickly.

One low current output power source is the USB port on a regular computer. A standard USB 2.0 port provides 500mA (0.5A) current per port, while USB 3.0 provides 900mA (0.9A) per port. For comparison, some dedicated chargers can output 3000-4000mA (3-4A). The low current ratings of USB ports generally ensure safe, normal temperature charging for most modern lithium-ion batteries.

Tip 5: Use a spare battery if possible

If your device allows for quick battery replacement, having a spare battery is a great insurance policy. This not only doubles the operating time of the device, but also eliminates the need to completely discharge the battery or use a fast charge. When the battery charge reaches 15-20 percent, simply replace the dead battery with a spare one, and you will instantly get a full charge of the device without any overheating problems.

A spare battery has other benefits as well. For example, if you find yourself in a situation where the installed battery becomes overheated (for example, due to heavy use of the device or high ambient temperatures), you can replace the hot battery to cool it down faster while continuing to use the device.

Having two batteries eliminates the need for fast charging - you can safely use the device while the battery is slowly charging from a safe power source.

Fred's Fatal Mistakes

Fred suggested that he might have damaged his smartphone battery during a road trip. He used the device's GPS feature to navigate during a clear, sunny day. The smartphone was left in the sun for a long time in a holder near the dashboard of the car; the brightness of the smartphone was turned on to maximum in order to distinguish the map among the bright rays of the sun.

In addition, all the standard background applications - email, instant messenger, etc. were launched. The device used a 4G module to download music tracks and a Bluetoorth wireless module to transmit sound to the car's head unit. The phone was definitely working under stress.

In order for the phone to receive power, it was connected to a 12V adapter, purchased based on the criteria of low price and availability of the correct connector.

The combination of direct sunlight, high processor load, the screen turned on at maximum brightness, and the questionable quality of the adapter led to excessive overheating of the smartphone. Fred remembers with horror how hot the device was when pulled out of the holder. This severe overheating was precisely the catalyst for the death of the battery.

Apparently, the problem got worse at night when Fred left the device plugged in all night using a third-party charger without checking when the battery was fully charged.

With his new smartphone, Fred will only use the included charger and spare battery. Fred hopes for a long and safe life for both the battery and the phone, which he plans to achieve with the help of the tips listed.

Found a typo? Highlight and press Ctrl + Enter

Testing Features

The main difficulty in the experiments is the discrepancy between the declared capacity and the real one. All batteries have a capacity higher than stated, ranging from 0.1% to 5%, which introduces an additional element of unpredictability.

NCA and NMC batteries were most commonly used, but lithium cobalt and lithium phosphate batteries were also tested.

A few terms:
DoD - Depth of Discharge - depth of discharge.
SoC - State of Charge - charge level.

Using Batteries

The number of cycles

This curve is called the Wöhler curve. The main idea came from mechanics about the dependence of the number of stretches of a spring on the degree of stretching. The initial value of 3000 cycles at 100% battery discharge is a weighted average at 0.1C discharge. Some batteries show better results, some worse. At a current of 1C, the number of full cycles at 100% discharge drops from 3000 to 1000-1500, depending on the manufacturer.

In general, this relationship, presented in the graphs, was confirmed by the results of experiments, because It is advisable to charge the battery whenever possible.

Calculation of superposition of cycles

According to the results of the experiments, the combined cycle showed results similar to the addition of complete equivalent cycles of two independent cycles. Those. The relative capacity of the battery in the combined cycle fell according to the sum of the discharges in the small and large cycles (the linearized graph is presented below).


The effect of large discharge cycles is more significant, which means that it is better to charge the battery at every opportunity.

Memory effect

Battery storage

Storage temperatures

Charge level

Main problems of the experimental results

Results of the experiments

Sources

Currently, smartphones and tablets use lithium-based batteries and lithium-polymer batteries.

Each of them has its own resource, which depends on the correct charging and operating conditions. There is also the concept of a “charging cycle” - today we will find out what it is.

What is a charging cycle?

The charging cycle is a set of processes associated with filling the battery with energy and completely discharging it. Their number determines how many times the battery can be charged and discharged.

There is no exact data on the number of cycles for lithium batteries, as these numbers may vary depending on proper use. On average, the resource of such batteries is 600-800 pieces. This figure may seem small to some, but if we assume daily charging and discharging, then 800 cycles - 800 days, that is, more than two years.

How many charge cycles are left?

Let’s imagine a situation where within two days the phone was discharged by 50% both times and was required to be charged to 100%. In this case, 1 charge cycle was used. Such moments can be repeated regularly, which leads to slower depletion of cycles and extends battery life. For this reason, many experts recommend not waiting for your smartphone to be deeply discharged and charging it regularly.

There is a relationship between the remaining energy in the battery and the number of cycles. Remaining charge level, % - remaining number of cycles:

• 90 - 4700.
• 75 - 2500.
• 50 - 1500.
• 0 - 500.

The table shows that if you discharge your smartphone by 50% every day, the number of charge cycles will be about 1500.

What's the best way to charge your smartphone?

It is important to understand that you cannot keep a fully charged smartphone constantly connected to a charger, for example. No, overcharging will not occur, since the charging controller will stop the flow of current, but a constant drop in the energy reserve to 99% and the subsequent replenishment to 100% will lead to a decrease in the number of charge cycles.

Recharging the battery, which occurs under the control of the user, has proven itself best. As soon as 90-100% is reached, you need to disconnect the gadget from the network. Of course, in everyday life it is difficult to ensure ideal battery operating conditions, but we must try to follow.

The following factors influence the reduction in the number of possible battery charge cycles and the reduction in its capacity:

• battery overheating;
• regular depletion of charge to 0%;
• using a non-original charger ().

Even if you manage to extend the life of the battery by 2-3 years, the natural aging of its constituent elements will still lead to a decrease in capacity by 15-20%.

Owners of various devices sometimes experience certain difficulties when finding information about the proper use of batteries. This short FAQ is devoted to this issue.
All modern phones, smartphones and PDAs are equipped with lithium-based batteries - lithium-ion or lithium-polymer, so in the future we will talk about them. These batteries have excellent capacity and service life, but require very strict adherence to certain operating rules.

The fundamental rules for charging and discharging batteries, which are controlled by a device (controller) built into the battery, and sometimes by an additional controller located outside the battery, in the PDA itself.

The battery must remain in a state during its entire life in which its voltage does not exceed 4.2 volts and does not fall below 2.7 volts. These voltages are indicators of the maximum (100%) and minimum (0%) charge, respectively.

The amount of energy supplied by a battery when its charge changes from 100% to 0% is its capacity. Some manufacturers limit the maximum voltage to 4.1 volts, while the battery lasts longer, but its capacity is reduced by about 10%. Also, sometimes the lower threshold rises to 3.0 volts with the same consequences.

Battery life is best at approximately 45 percent charge, and as the charge level increases or decreases, battery life decreases. If the charge is within the limits provided by the battery controller (see above), the change in durability is not very significant, but is still present.

If, due to circumstances, the voltage on the battery exceeds the limits specified above, even for a short time, its life is dramatically reduced. Such conditions are called undercharge and overdischarge and are very dangerous for the battery.

Battery controllers designed for different devices, if they are made with proper quality, never allow the battery voltage to exceed 4.2 volts during charging, but, depending on the purpose of the battery, may limit the minimum voltage during discharge in different ways. So, in a battery intended for, say, a screwdriver or a car model motor, the minimum voltage will most likely be truly the minimum permissible, but for a PDA or smartphone it will be higher, because the minimum voltage of 2.7 volts may simply not be enough to operate the electronics of the device. That is why in complex devices such as phones, PDAs, etc. The operation of the controller built into the battery itself is complemented by the controller in the device itself.

Operating rules that you and I can influence, thereby significantly increasing or decreasing the battery life.

1. you need to try not to bring the battery to a minimum charge, and even more so to a state where the machine turns itself off, but if this happens, charge the battery as soon as possible.
2. There is no need to be afraid of frequent recharges, including partial ones, when a full charge is not achieved. This does not harm the battery. In this case, I am guided by common sense: if during normal use of a PDA I always put it on charge before going to bed, then in the case of very intensive use (WiFi always on, listening to music, etc.), when the charge approaches the minimum, I do not disdain directly At work, connect the PDA to any available USB. If you don’t have a normal charger and use a special USB charger instead, it is important not to wait until the charger is completely discharged, because in this case the current from the USB port may not be enough to start the charging process.
3. Contrary to the opinion of many users, overcharging harms lithium batteries no less, and even more, than deep discharging. The controller, of course, controls the maximum charge level, but there is one subtlety. It is well known that battery capacity depends on temperature. So, if, for example, we charged the battery at room temperature and received a 100% charge, then when we go out into the cold and the machine cools down, the battery’s charge level may drop to 80% or lower. But the opposite situation may also be true. A battery charged at room temperature to 100%, when slightly heated, will become charged to, say, 105%, and this is very, very unfavorable for it. Such situations occur when operating a machine that has been in the cradle for a long time. During operation, the temperature of the device and along with it the battery rises, but the charge is already full... In this regard, the rule says: if you need to work in the cradle, first disconnect the machine from the charger, work on it, and when it goes to " combat" mode - connect the charger. By the way, this rule also applies to owners of laptops and other gadgets.
4. Ideal conditions for long-term battery storage are to be outside the device with a charge of approximately 50%. A working battery does not require care for months (about six months).

And finally, some more information.

1. Contrary to popular belief, lithium batteries, unlike nickel ones, have almost no “memory effect”, so the so-called “training” of a new lithium battery makes virtually no sense. For your own peace of mind, it is enough to fully charge and discharge the new battery once or twice, mainly to calibrate the additional controller.
2. Device owners know that you can charge the battery both from a charger and from USB. At the same time, the impossibility of charging from USB often causes bewilderment. The fact is that, according to the “law,” a USB controller must supply a current of about 500 mA to peripheral devices connected to it. However, there are situations when either the controller itself cannot provide such a current, or the device is connected to a USB controller on which some kind of peripheral is already hanging, consuming some of the power. So there is not enough current for charging, especially if the battery is too discharged.
3. Lithium-containing batteries REALLY DO NOT LIKE FREEZING. Always try to avoid using the machine in severe cold - if you get carried away, the battery will have to be changed. Well, of course, if you took the machine out of the warm inner pocket of your jacket and made a couple of notes or calls, and then put the little animal back, there will be no problems.
4. Practice shows that lithium batteries (not just batteries) reduce their capacity when atmospheric pressure decreases (at high altitudes, on an airplane). This does not harm the batteries, you just need to take this fact into account.
5. It happens that after purchasing a battery with a higher capacity (say, 2200 mAh instead of the standard 1100 mAh), after a couple of days of using the new battery, the machine begins to behave strangely: it hangs, turns off, the battery seems to be charging, but somehow strange, etc. P. It is possible that your charger, which works successfully on a “native” battery, is simply not able to provide sufficient charging current for a high-capacity battery. The solution is to purchase a charger with a higher current output (say 2 amperes instead of the previous 1 ampere).

19.10.2010 10:53

Original taken from kolochkov in Rules for the use of lithium-ion batteries

We are already tired of writing and speaking the same misconceptions about lithium-ion batteries.
To stop this madness, I quote from the “Rules for the Use of Lithium-Ion Batteries” by one respected source:

Proper use of cell phone batteries

• The electrodes of lithium-ion batteries are already half charged due to the manufacturing process, but it is not advisable to immediately test a fresh battery under load. Initially, the lithium-ion battery needs to be fully charged. Using a battery without an initial charge can dramatically reduce the capacity available to the user.
• After initially charging the battery, it is advisable to completely discharge it to calibrate the battery management system. Recharge the battery immediately after discharge. Calibration cycles for cell phones with lithium-ion batteries should not be performed frequently (usually one full charge-discharge cycle every 3 months is enough). The calibration cycles themselves are needed only to correctly display the forecast of the remaining battery capacity. The three to four deep charge-discharge cycles recommended by some users and sellers can be fatal for a not new lithium-ion battery.
• It is advisable to use original batteries from the mobile phone manufacturer. Since the functions of the battery management system for mobile phones are greatly reduced, and the charge is controlled by the cell phone charging system, a battery from a third-party manufacturer will last less, since the charging system does not know the features of non-original batteries.
• Due to the fact that the “aging” effect of lithium-ion batteries increases sharply at high temperatures, it is advisable to keep the cell phone away from heat sources (human body, direct sunlight, heating radiator).
• It is advisable not to fully charge the cell phone battery often, and also to charge the battery before the charge level reaches the red level of the charge indicator (approximately 20% of the remaining capacity).
• The aging of lithium-cobalt batteries (the most common batteries for cell phones directly depends on the load level). Talk less and less often on your mobile phone - this will keep not only your battery healthy, but also you.
• Do not charge a battery that has been in the cold until it warms up to a positive (Celsius) temperature - this is an important requirement for the safe operation of lithium-ion batteries.

• The laptop battery contains a complete management system, which often allows the user to forget whether he is using the battery correctly. However, there are a few things to keep in mind when working with a laptop.
• When connecting for the first time, the laptop battery should be fully charged, and then calibrate the control system. Calibration is carried out by completely discharging the battery under constant load (you need to enter the BIOS settings and leave the laptop running when unplugged until turned off; many BIOS adjusters have a special Calibration item designed to perform this task). Make sure to charge your laptop battery immediately after it is completely drained.
• Calibration of a laptop battery is usually carried out once every 1-3 months, to eliminate the effect of “digital memory” - during operation on battery power, errors in determining the residual capacity gradually accumulate, which reduces the battery life of the laptop.
• For some laptop models, there are manufacturer utilities for setting the level of battery discharge at which charging begins. If the laptop battery serves as an uninterruptible power supply (work is carried out stationary with mains power), then setting the permissible discharge level to 40% and maintaining the battery in a half-discharged state will double the battery life.
• Some laptops come with an extra battery. If you do not use it for a long time, it makes sense to discharge the additional battery to 40%, pack it in a plastic bag with a vacuum seal and leave the bag in the refrigerator compartment at a temperature of 3-4°C.

• The rules for using Power Tools batteries (mainly screwdriver batteries) and video cameras differ little from the rules for using cell phone batteries.
• The difference is that the use of these devices in everyday life is quite rare, and the cost of batteries is high and these batteries become less accessible over time. To ensure a long life of such batteries, they should be stored in a semi-discharged state in the refrigerator at a temperature of 3-4°C, pre-packed in a plastic bag with a vacuum seal. Before use, the battery must be fully charged using a standard charger, and during operation, the battery must not be completely discharged (at the first opportunity, recharge the battery during operation).
• In conclusion of the article, I would like to say that although the operating rules allow you to maintain battery parameters for a long time, life dictates its own operating conditions, which are often incompatible with the concept of proper operation of such a high-tech thing as a lithium-ion battery.

Lithium-ion batteries are not as finicky as their nickel-metal hydride counterparts, but they still require some care. Sticking to five simple rules, you can not only extend the life cycle of lithium-ion batteries, but also increase the operating time of mobile devices without recharging.

Do not allow complete discharge. Lithium-ion batteries do not have the so-called memory effect, so they can and, moreover, need to be charged without waiting for them to discharge to zero. Many manufacturers calculate the life of a lithium-ion battery by the number of full discharge cycles (up to 0%). For quality batteries this 400-600 cycles. To extend the life of your lithium-ion battery, charge your phone more often. Optimally, as soon as the battery charge drops below 10-20 percent, you can put the phone on charge. This will increase the number of discharge cycles to 1000-1100 .
Experts describe this process with such an indicator as Depth Of Discharge. If your phone is discharged to 20%, then the Depth of Discharge is 80%. The table below shows the dependence of the number of discharge cycles of a lithium-ion battery on the Depth of Discharge:

Discharge once every 3 months. Fully charging for a long time is just as harmful to lithium-ion batteries as constantly discharging to zero.
Due to the extremely unstable charging process (we often charge the phone as needed, and wherever possible, from USB, from a socket, from an external battery, etc.), experts recommend completely discharging the battery once every 3 months and then charging it to 100% and holding it on charge 8-12 hours. This helps reset the so-called high and low battery flags. You can read more about this.

Store partially charged. The optimal condition for long-term storage of a lithium-ion battery is between 30 and 50 percent charge at 15°C. If you leave the battery fully charged, its capacity will decrease significantly over time. But the battery, which has been collecting dust on a shelf for a long time, discharged to zero, is most likely no longer alive - it’s time to send it for recycling.
The table below shows how much capacity remains in a lithium-ion battery depending on storage temperature and charge level when stored for 1 year.

Use the original charger. Few people know that in most cases the charger is built directly into mobile devices, and the external network adapter only lowers the voltage and rectifies the current of the household electrical network, that is, it does not directly affect the battery. Some gadgets, such as digital cameras, do not have a built-in charger, and therefore their lithium-ion batteries are inserted into an external “charger”. This is where using an external charger of questionable quality instead of the original one can negatively affect the performance of the battery.

Avoid overheating. Well, the worst enemy of lithium-ion batteries is high temperature - they absolutely cannot tolerate overheating. Therefore, do not expose your mobile devices to direct sunlight or place them near heat sources such as electric heaters. Maximum permissible temperatures at which lithium-ion batteries can be used: from –40°C to +50°C

Also, you can look