14.8V 20Ah 18650 Lithium ion Rechargeable Battery Pack

Lithium battery protection: short circuit protection, overcharge protection, over-discharge protection, over current protection, etc.
Application areas: wireless monitoring terminal, detection and control instruments, etc.
We are happy to custom charge & discharge current to meet customer requests.

Effects of lithium-ion battery self-discharge:

1. Self-discharge leads to a decrease in capacity during storage Several typical problems caused by excessive self-dischargeA. The car has been parked for too long and cannot be started;
   B. The voltage of the battery before storage is normal, and the low voltage or even zero voltage is found when it is shipped;
   C. In summer, the car GPS is placed on the car, and after a period of time, it feels that the power or use time is obviously insufficient, and even the battery is bulging.
2. Metal impurity type self-discharge leads to blockage of the diaphragm aperture, and even pierces the diaphragm to cause a partial short circuit, endangering the safety of the battery;
3. Self-discharge leads to an increase in the SOC difference between cells and a decrease in the capacity of the battery pack;
4. Large differences in SOC can easily lead to overcharge and over-discharge of the battery;

lithium li-ion battery self-discharge test method:

• Voltage drop method 

  The magnitude of self-discharge is characterized by the rate of voltage reduction during storage. This method is simple to operate, but the disadvantage is that the voltage drop cannot intuitively reflect the loss of capacity. The voltage drop method is the simplest and most practical, and is the method commonly used in current production.

• Capacity decay method 

  That is, the percentage of capacity reduction per unit time is expressed.

• Self-discharge current method 

  According to the relationship between capacity loss and time, the self-discharge current Isd during battery storage is calculated.