Here's The Mistake You Shouldn't Make When Buying A Used Electric Car

Here’s the mistake you shouldn’t make when buying a used electric car

Last updated: 2025/11/28 at 5:36 AM

News Room Published 28 November 2025

The electric car market is exploding, and with it that of used resale. The fact remains that unlike a thermal model, where mileage constitutes one of the most important arguments in favor (or not) of the sale, this is not what matters most on electric models. Two models identical in age and kilometers can have a very different Price on the market. With lithium-ion batteries, a fundamental criterion emerges: State-of-Health, or SoH. This indicator, expressed as a percentage, measures the residual capacity compared to new condition. A 90% SoH means the battery retains the majority of its initial performance. Conversely, an SoH below 80% is a bad sign for the future.

Don’t make this mistake

This is a common mistake made by many thermal drivers who decide to go electric. Not paying attention to SoH is like making a blind purchase, since you don’t know what condition the battery of your future car is in. On average, the SoH drops to 90% after 100,000 km. But substantial differences exist depending on use: frequent fast charging, aggressive driving or extreme temperatures are all elements that accelerate battery degradation.

In use, a degraded SoH results in a loss of autonomy and slower charging. It is therefore essential to ask the seller to tell you the SoH of the car you are considering purchasing second-hand. Europe has already anticipated the problem with the battery passport, compulsory from February 2027 for all new EVs over 2 kWh. This digital document, accessible via QR code, will detail the origin of the materials, CO2 emissions, recyclability and above all the SoH in real time.

How to preserve your SoH?

To maintain the capacity of your battery for as long as possible, rely on slow recharging between 20% and 80% at room temperature, which preserves the cells. It is also possible to carry out a paid diagnosis at garages or via dedicated kits. The fact remains that control is vague and subject to falsification. Be careful not to take everything at face value. For their part, the manufacturers often guarantee up to 70% capacitybeyond which replacement will be recommended. While waiting for 2027, prioritize SoH over km: ask the seller for a certificate, and avoid fast charges that are too frequent in the vehicle’s history.