SOH
PerformanceAlso known as: State of Health
State of Health (SOH) measures how much of a battery's original capacity remains after use and aging. A new battery starts at 100% SOH; as it degrades through cycling and calendar aging, SOH gradually declines.
SOH is tracked by the BMS and verified through periodic Round-Trip Performance Tests (RPTs). It is a key metric for warranty compliance — manufacturers guarantee a minimum SOH at specific intervals (e.g. 80% SOH after 10 years). When SOH drops below the warranty threshold, the asset owner may need to augment the system with additional battery capacity.
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