Electric vehicle (EV) batteries retain more than 90% of their capacity after six years on average, according to new analysis from leasing company Arval based on 24,000 battery health certificates.
The findings suggest battery degradation is significantly lower than many buyers expect, offering reassurance to drivers considering switching to an EV or purchasing one on the used market.
Arval’s study analysed battery State of Health (SoH) certificates issued across 11 European countries, covering vehicles remarketed between March 2023 and September 2025.
On average, batteries still deliver 93% of their original capacity after 70,000km.
Even after 160,000km or six years of use, battery health typically remains above 90%.
The data also shows degradation occurs slowly and predictably, with battery performance declining by around 1% every 25,000km following a small initial drop.
EV batteries remain durable over long periods of real-world use
Arval said the findings reinforce growing evidence that EV batteries remain durable over long periods of real-world use, helping to address lingering concerns among used car buyers.
Pascal Seeger, global remarketing director at Arval, said: “This update fully confirms the insights shared last year: batteries maintain a high level of performance over time, beyond market perceptions.
“This is very good news for used car buyers, who can be confident in the durability and reliability of EV batteries over the long run.
“By providing consolidated and comparable data, we help remove barriers to buying used EVs and accelerate the development of a more transparent and reliable market.”
The analysis also identified improvements in newer EVs.
Models benefiting from more advanced battery design, cooling and energy management systems typically showed battery health two to three percentage points higher than earlier vehicles.
Arval has issued more than 30,000 battery health certificates since launching its programme, which provides an independent assessment of battery condition when vehicles are remarketed.
Gary Burns, director of procurement and remarketing at Arval UK, said: “As electric vehicles move into the used market in greater volumes, transparency around battery condition is increasingly important.
“We want our customers to be able to purchase our vehicles with confidence, which is why battery health testing has become a significant part of our remarketing process.
“Encouragingly, the results we’re seeing show that batteries in used EVs stand up well in real-world use, helping to reassure buyers considering this fuel type.”
Arval works with independent battery testing specialists Moba and Aviloo to provide the certificates, which are designed to give buyers and sellers a consistent and reliable assessment of battery condition.
The company said upcoming European regulation will further improve transparency.
Under future Euro 7 and battery rules, battery health will be standardised and displayed directly within vehicles, while each battery will also be accompanied by a digital “Battery Passport” documenting its history and certified capacity.