In one line
The current available energy in a battery expressed as a percentage of its full capacity.
What it means
State of Charge (SoC) expresses the current available energy in a battery as a percentage of its full capacity. SoC management is a primary BMS function. Most stationary BESS systems operate within a 10–90% SoC window to extend cell life, sacrificing 20% of nameplate capacity for cycle longevity.
Related terms
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