What is Battery State of Health?

Battery state of health, often abbreviated SOH, is a measure of how much capacity an electric vehicle's battery retains compared to when it was new, expressed as a percentage. A battery at 90 percent state of health can store about 90 percent of its original energy, meaning slightly reduced range. State of health matters most for used EVs, where it directly affects value, usable range, and remaining warranty. For dealers appraising or selling pre-owned electric vehicles, checking and disclosing state of health is becoming as important as odometer reading on a gas car, since it is a key material fact for buyers. Many EVs report state of health through onboard diagnostics or manufacturer tools. Providing a clear state-of-health reading builds trust with EV buyers, supports accurate pricing, and helps avoid disputes about degraded range after the sale.