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EV value: how battery health affects the price

The battery is the most expensive component in an EV, and its health (SOH — State of Health) is the first thing experienced buyers ask about. Below 90% it starts to show in the price. Find your EV and see what battery health typically means in kroner.

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You'll find SOH in a workshop battery test, in some cars' infotainment, or in service reports. If you don't know the value, leave it — 90% or more counts as normal wear.

Unsure? Most EVs under 8 years old sit at 88–95%.

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How we calculate the estimate

The base value uses the same residual value curve as the depreciation calculator, with separate calibration for EVs (June 2026). The SOH adjustment is a conservative step model: 90–100% gives no adjustment, 80–89% deducts about 5%, 70–79% about 12%, and below 70% about 22%. The figures are conservative approximations based on observed price differences — not a per-model verdict.

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EV vs petrol and diesel

EVs have dropped in value faster than comparable petrol and diesel cars in recent years, mainly due to price pressure from ever-cheaper new models with longer range. At the same time, running costs are lower, so the buyer's total math is often better than the price drop suggests. For you as a seller, this means documented battery health and the right price from the start are what actually sell a used EV.

Battery health measured as SOH indicates how much capacity the battery retains compared to when it was new. A battery at 90% SOH in a car with an original range of 400 km gives roughly 360 km — a difference most people barely notice day to day. That is why the price impact is small as long as the battery is within normal wear.

Below 80%, the picture changes. The range loss becomes noticeable, buyers start pricing in the risk of a battery replacement, and the car becomes harder to sell without documentation. A fresh workshop battery test typically costs a few hundred kroner and is the best investment you can make before selling an older EV.

Also remember the battery warranty: most manufacturers guarantee at least 70% capacity for 8 years or 160,000 km. A car approaching the warranty threshold with a documented weak battery can actually be worth more than the numbers suggest — a warranty replacement effectively means a new battery. Check the terms for your model before setting a price.

Questions and answers

Frequently asked questions

What is SOH, and how do I measure it?
SOH (State of Health) is the battery's remaining capacity as a percentage of its original capacity. Many newer EVs show SOH in the car's own menus, and brand workshops and battery test services can measure it precisely. A written test report is good documentation for a sale and usually costs a few hundred kroner.
How much value does an EV lose if the battery is weak?
Within normal wear (90% SOH or better) the impact is small. Between 80 and 89% it typically deducts around 5% of the value, between 70 and 79% around 12%, and below 70% the impact becomes large — often 20% or more — because the buyer must budget for battery measures. The figures vary by model, so treat them as approximations.
Does the battery warranty cover a weak battery?
Most manufacturers guarantee that the battery retains at least 70% capacity for 8 years or 160,000 km, whichever comes first. If capacity falls below the threshold within the warranty period, the battery is repaired or replaced free of charge. The warranty normally follows the car, not the owner — documentation that the terms are met therefore adds value at sale.
Do EVs depreciate more than petrol cars?
In recent years, EVs have on average dropped faster than comparable petrol and diesel cars, primarily because new EVs have become cheaper and better at a rapid pace. The difference varies a lot between models, and the picture can change. For sellers, it means the right price from the start and documented battery health matter more than ever.

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