# What can you learn from the specification of the battery? Take CATL 3.2V 120Ah for example.

#C-Rate

The ratio of the charging current to the capacity of the battery. For example: when the battery capacity is 120Ah and the charging current is 60A, the C-Rate is 0.5C; when the battery capacity drops to 120Ah and the charging current is 240A, the C-Rate is 2C.

#Cycle

The battery is charged and discharged once for one cycle according to the specified charging and discharging standards.

#OCV = Open circuit voltage

Voltage of the battery measured without any load or circuit connected.

#SOC = State of Charge

In the case of no load, all linear relationships of the state of battery charge capacity measured in ampere-hours or watt-hours. For example, if the capacity of 120Ah is regarded as 100% SOC, when the capacity is 0Ah, the SOC is 0%.

#Standard charging mode

Charge the battery to the charging cut off voltage 3.65V with 0.5C constant current, and then constant voltage charge battery at 3.65V until the current lower limit is 0.05C.