State of health (SoH)

State of health (SoH) is a measure of a battery’s current condition relative to its original specification, typically expressed as a percentage that reflects how much usable capacity or performance remains after ageing and use. Regulation (EU) 2023/1542 requires that data needed to determine state of health and expected lifetime be recorded and made available for LMT, industrial (above 2 kWh), and EV batteries, and this dynamic data forms part of the battery passport. Accurate SoH information is essential for safe repurposing and second-life decisions.