TCS Analysis: Batteries in Used Electric Vehicles Mostly in Good to Very Good Condition

An increasing number of electric vehicles are now available on the second-hand market. Similar to conventional combustion engines, there is often uncertainty about the quality condition of used vehicles, and for e-cars, this uncertainty relates to the state of the high-voltage battery. This component can account for 30 to 50 percent of the total cost of an electric vehicle. Its condition directly affects the residual value, lifespan, and maintenance costs of the vehicle. Additionally, the battery is a critical component for range, making it one of the most important purchasing criteria. The SoH value provides an initial general indication of the high-voltage battery's condition.

Analysis of 130 Vehicles

Vehicles tested by the technical centers of the TCS sections in Zurich, Bern, Biel, and Vaud between January and September 2025 were examined. The analysis is based on SoH values provided by the manufacturer, read via an Aviloo device through the vehicle's diagnostic port. Data from around 130 vehicles were evaluated for the analysis.

For comparability, the vehicles were divided into four classes based on age (up to five years or older than five years) and mileage (up to 75,000 or over 75,000 kilometers): A (<= 75,000 km, <= 5 years), B (<= 75,000 km, > 5 years), C (> 75,000 km, <= 5 years), and D (> 75,000 km, > 5 years).

Batteries Mostly in Good to Very Good Condition

Vehicles with less than 75,000 kilometers and less than five years account for nearly two-thirds of the sample. For 87 percent of them, the measured SoH is over 90 percent, with none falling below 85 percent. Class C, also under five years old, also shows good SoH values despite intensive use.

The lowest SoH values, below 85 percent, mainly concern first-generation models (around 2019 and earlier) or vehicles with a mileage of more than 200,000 km. In the sample, these generally involve advanced age with low mileage (class B vehicles) or high mileage (class D vehicles). Therefore, purchasing such a vehicle should be considered with more caution. Nonetheless, six of the 17 class B vehicles, and almost half of class D, showed an SoH of around 90 percent or more. Notably, all batteries at the end of their lifespan belonged to first-generation electric vehicles and were older than eight years.

Battery Certificate Offers Security

TCS recommends that buyers request a battery certificate when purchasing a used vehicle to gain clarity about the condition of the battery and make a fair assessment of the vehicle's value. TCS technical centers offer used car tests including battery certificates.

New Battery Passport in the EU from 2027

From 2027, digital battery passports will be mandatory for electric vehicles in the EU. Vehicles later imported into Switzerland will also need to fulfill this proof requirement. Swiss dealers and buyers will thus automatically benefit from greater transparency, similar to the CE mark, which is accepted beyond the EU.

Press Contact:
Vanessa Flack, TCS Spokesperson
Tel. 058 827 34 41
vanessa.flack@tcs.ch

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