How to Store Li-Ion Batteries in Cold Weather

Overview

Lithium-ion batteries also have a limited lifespan, and good storage can extend the lifespan of lithium-ion batteries. Many people choose to use batteries seasonally, whether it's winter or summer. Therefore, it is very important to store the battery.

What happens to batteries in cold weather

Generally, the battery has an impact on the positive and negative electrodes and the electrolyte in a low-temperature environment. At low temperatures, the viscosity of the electrolyte will increase, and the resistance to the movement of lithium ions will also increase. And it is easy to generate polarization, thereby reducing the battery capacity. Affected by the low temperature, the speed of graphite intercalation decreases, and it is easy to precipitate metallic lithium on the surface of the negative electrode. If it is put into use after charging for insufficient time, the metallic lithium cannot be re-inserted into the graphite again, and some metallic lithium persists on the surface of the negative electrode, which is very likely to form. Lithium dendrites affect battery safety.

It is necessary to completely disconnect the power

Many users have the habit of directly disconnecting the main switch, thinking that this will cut off all the power. It is not, especially in applications like RVs, in many cases people think that the power supply is completely disconnected from its sensors and emergency sensors are still running. This will continue to consume battery capacity. If the storage time is not very long, the impact is not great. If it is not used for half a year or a few years, the battery power will eventually be exhausted. This is irreversible damage to the battery.

Lithium batteries are necessary to store power in cold weather

It needs to be charged before storage, and the SOC is kept between 50%-80%. If the battery is stored without charging, its charge may drop under the protection of the BMS. It is very difficult to wake up the battery again, and even if it is woken up, the battery will be damaged and its shelf life will expire. Therefore, if you want to keep the battery in a very good state, you should keep the battery in a charged state until the end of the storage period.

How often to check the battery

Lithium-ion batteries are inspected every 3 months so that you can know if the battery is in an abnormal state. For lead-acid batteries, it needs to be checked every 2-3 weeks. The reason why the inspection time of Li-ion batteries does not need to be so short is that Li-ion batteries are more stable than lead-acid batteries.

Clean the battery

Dirt and corrosion can speed up battery self-discharge and can also affect battery life. If the battery is not kept clean, a short circuit of the battery will occur.

Preheat the battery before using it

The battery needs to be preheated before use, and then the battery will generate heat. This is because, under the protection of low-temperature batteries, the metal lithium in the lithium-ion battery is deposited and no longer chemically reacts with other substances. Lithium-ion batteries work by chemically reacting the electrolyte, resulting in an electric current. But at low temperature, the electrolyte moves very slowly, which affects the activity of lithium ions. This is why the car needs to be warmed up before charging the battery.

Conclusion

In cold weather, the activity of lithium ions decreases, resulting in poor discharge performance. If you want to extend the service life of lithium-ion batteries and maximize the use function, you must pay attention to the maintenance of lithium-ion batteries.