In one line
A battery's current maximum capacity expressed as a percentage of its original rated capacity.
What it means
State of Health (SoH) measures a battery's current usable capacity relative to its rated original capacity. SoH degrades over cycles and time. LFP BESS warranties typically guarantee SoH above 70–80% at end-of-warranty (often 10 years or specified cycle count).
Related terms
Browse every term in the renewable energy glossary, or read the latest analysis on Battery storage.