The State of Health (SoH) of a battery is the indicator that measures how much a battery has degraded compared with when it was new: typically the current capacity expressed as a percentage of the original. A battery at 90% SoH has lost 10% of its initial capacity.
Why it matters for electric vehicles
As fleets electrify, SoH becomes a key metric: it determines real range, how plannable missions are, and above all the vehicle’s residual value (the battery is the most expensive component). A monitored SoH avoids nasty surprises at resale or lease-end.
How it’s monitored
SoH is derived from on-board telematics data (charge cycles, temperatures, usage). Tracking it over time feeds predictive maintenance and renewal decisions. On what telematics really monitors on EVs, see beyond GPS: next-generation telematics and EV telematics and fleet monitoring.
FAQ
What does a battery at 80% SoH mean?
That its usable capacity has dropped to 80% of the original: range is reduced by about a fifth. 80% is often used as an indicative end-of-life threshold for automotive use.
Can SoH be measured without a workshop?
Yes: the vehicle’s telematics data lets you estimate and track SoH over time, with no dedicated intervention, integrated into fleet monitoring.