LiFePO4 Battery and the Zero Voltage Test

The full name of LiFePO4 battery is lithium iron phosphate lithium ion battery, which is too long, referred to as lithium iron phosphate battery.

Working principle

Lithium iron phosphate battery is a lithium ion battery using LiFePO4 as cathode material. The cathode materials of lithium ion batteries include lithium cobalt oxide, lithium manganese oxide, lithium nickel sulfate, three element material, lithium iron phosphate, etc.. Among them, lithium cobalt oxide is the most used cathode material for lithium ion batteries.

As the battery requirements are: high capacity, high output voltage, good cycling performance, stable output voltage, high current charge discharge and electrochemical stability, the use of security (not due to overcharge and overdischarge and short circuit operation caused by improper combustion or explosion), wide temperature range, non-toxic or less toxic, no pollution to the environment. The lithium iron phosphate battery using LiFePO4 as anode in the performance requirements are good, especially in the high rate discharge discharge (5 ~ 10C discharge), stable discharge voltage, safe (no burning, no explosion), long life (cycles), no pollution to the environment, it is the best. Is currently the best high current output power battery.

Over discharge to zero voltage test:

Test of over discharge to zero voltage by using 26650 (3300mAh) LiFePO4 Battery . Test conditions: the 3300mAh battery is filled with 0.5C charge rate, and then discharge to the battery voltage of 0C with 1.0C discharge rate of STL18650. The batteries placed in 0V were divided into two groups: one group was stored for 7 days, another group was stored for 30 days; after storage expired, the 0.5C charging rate was filled, and then discharged with 1.0C. Finally, the differences between the two zero voltage storage periods are compared.

The test result shows that the battery has no leakage after zero voltage storage for 7 days, the performance is good, the capacity is 100%; after 30 days of storage, no leakage, good performance, the capacity is 98%; after 30 days of storage, the battery will do 3 cycles of charging and discharging, and the capacity will be restored to 100%.

This test shows that the lithium iron phosphate battery does not leak or damage even if it has been discharged (even to 0V) and stored for a certain period of time. This is a characteristic that other lithium ion batteries do not have.