Starting next year, Belgian consumers buying a used electric vehicle will, for the first time, be able to check the battery’s condition on the official Car-Pass, the document that certifies a vehicle’s history and which is mandatory in this country.
Still, the battery’s condition health state mention will remain optional until Europe’s digital battery passport becomes mandatory on 18 February 2027. Designed to track every stage of a battery’s life, from raw materials to recycling, that system still lacks clear technical standards and data definitions.
Transparency in the used EV market
The Belgian initiative, agreed to by Consumer Affairs Minister Rob Beenders (Vooruit) and Mobility Minister Jean-Luc Crucke (Les Engagés), aims to increase transparency in the growing second-hand EV market.
Until now, buyers could only see mileage, CO₂ emissions, and inspection data, while the most essential element —the battery’s State of Health (SoH) —remained a guess. Yet SoH largely determines an electric car’s value and range.
EU battery passport
A European regulation will make a ‘battery passport’ mandatory by 2027, but Belgium wants to move faster. From January 2026, the battery’s capacity, expressed as a simple percentage, can appear on the Car-Pass, provided the seller agrees to share it. The question is, what method to use, and who is going to certify this?
For now, there is no single European method to measure a battery’s State of Health (SoH). Each carmaker still relies on its own internal software, meaning results can differ from one brand to another.
Most carmakers determine a battery’s State of Health (SoH) through the vehicle’s Battery Management System (BMS). The software continuously tracks voltage, current, temperature, and charge cycles.
Using Coulomb counting, voltage analysis, and proprietary model-based algorithms, the BMS estimates the remaining capacity and power compared to when the battery was new.
While this approach works well for monitoring performance, each manufacturer uses its own calibration, meaning SoH figures can vary between brands. That’s one of the reasons Europe now wants a harmonised, transparent testing standard by 2027.
Using independent testers
In Belgium, the new Car-Pass system will use independent testers such as AVILOO, DEKRA, or TÜV Rheinland to verify the condition of the battery when sellers choose to share it. These voluntary certificates will bridge the gap until 2027, when the EU’s official digital battery passport and harmonised testing rules come into force across Europe.
AVILOO GmbH, based in Austria, offers a plug-in diagnostic test that measures a car’s actual battery State of Health (SoH) without relying on manufacturer data and issues a TÜV-certified report in minutes. Dealers and inspection centres across Europe already use it.
Other major players include DEKRA and TÜV Rheinland, which provide certified battery checks through their inspection networks, and Moba Certify in France, whose mobile app and OBD device let garages generate instant SoH certificates.
Bosch Mobility Solutions and Battery Quick Check (a TÜV–TWAICE partnership) are also developing cloud-based tools for fleets and resale markets.
In Belgium, these certified battery testers would perform the battery health check and send the verified results to Car-Pass vzw, the organization that manages the national Car-Pass database. Car-Pass then adds this information to the vehicle’s record, so the battery condition appears on the official Car-Pass document when the car is sold.
Who’s going to pay for this?
Newer EVs are far more durable than expected
What Belgium is trying to do is dispel the entrenched public misconception that electric-car batteries only last about 8 years or 100,000 kilometres before needing replacement. This assumption implies a costly problem.
When electric cars first hit the road, sceptics warned that their batteries would fade long before the rest of the vehicle. A decade later, that prediction looks increasingly outdated. Real-world data now show that modern EVs are aging gracefully, often far better than the early pioneers of electric mobility.
Active cooling or not
Take the first-generation Nissan Leaf or Renault Zoe: without active cooling, many of those early batteries lost noticeable capacity within a few years, especially in warmer climates.
But the new generation tells a very different story. Tesla’s Model 3, Volkswagen’s ID.3, and Hyundai’s Ioniq 5 typically retain around 90 percent or more of their original capacity even after 100,000 kilometres or more on the road.
The secret lies in more innovative engineering, improved battery chemistry, active liquid cooling, and sophisticated battery-management systems that control temperature and charging stress with far greater precision.
Most modern packs lose just a few percent in their first years before settling into a slow, predictable decline of roughly one to two percent per year. In reality, recent studies show that modern EV batteries degrade by only about 1.8 percent per year and often retain more than 80 percent of their capacity even after 200,000 kilometres.
That loss may slightly reduce range, but it doesn’t mean the battery must be replaced. In most cases, EV batteries continue to perform reliably for 15 to 20 years and, when they eventually reach the end of their automotive life, can often be reused for stationary energy storage.
Using AI, we dug through real-world data to see how the batteries of popular early EVs are holding up as they enter their “second life” as used cars.
| Make & Model | Years | Cooling | Battery (kWh) | Observed Data | Observed % Remaining | SoH @5 y / 100 k km | SoH @8 y / 160 k km |
|---|---|---|---|---|---|---|---|
| Tesla Model 3 / Y (Long Range) | 2019–present | Liquid | ~75–82 | ≈85 % capacity after 322 000 km | ≈85 % | ≈90–93 % | ≈85–90 % |
| Volkswagen ID.3 (Pro/Pro S) | 2020–present | Liquid | 58 / 77 | 91 % after 160 000 km (ADAC test) | ≈91 % | ≈90–93 % | ≈86–90 % |
| Nissan Leaf (early gens) | 2011–2017 | Air | 24 / 30 | First “bar” lost ≈3 years / 45 000 km | 70–85 % | ≈82–88 % (mild) / 75–85 % (hot) | ≈75–85 % (mild) / 65–80 % (hot) |
| Hyundai Kona Electric | 2019–present | Liquid | 64 | ≈90 % after 120 000 km | ≈90 % | ≈90–94 % | ≈86–90 % |
| Kia e-Niro / Niro EV | 2019–present | Liquid | 64 | ≈92 % after 5 yrs | ≈92 % | ≈90–94 % | ≈86–90 % |
| Hyundai Ioniq 5 | 2021–present | Liquid | 72.6 / 77.4 | ≈94 % after 3–4 yrs | ≈94 % | ≈90–94 % | ≈86–91 % |
| Renault Zoe (ZE 40/50) | 2017–2023 | Air | 41 / 52 | ≈80–90 % after 5–7 yrs | ≈85 % | ≈85–90 % (mild) / 80–87 % (hot) | ≈78–86 % (mild) / 72–82 % (hot) |
| BMW i3 (94–120 Ah) | 2016–2022 | Liquid | 33 / 42 | ≈90 % after 5–7 yrs | ≈90 % | ≈90–94 % | ≈85–90 % |
| Audi e-tron 55 | 2019–2023 | Liquid | 95 (usable ≈ 86–89) | ≈90 % after 5 yrs | ≈90 % | ≈89–93 % | ≈84–89 % |
Source: independent endurance tests, fleet datasets, and owner reports.
“SoH” = State of Health, meaning remaining usable battery capacity versus new.
Actual values vary with climate, charging habits, and driving style.
In short, today’s EV batteries are proving more challenging than anyone expected. Many are likely to last 15 to 20 years, well beyond the average lifespan of the car itself.
That makes ‘battery anxiety’, once a significant barrier to electric adoption, increasingly a relic of the past. The numbers now suggest that the question isn’t whether the battery will last, but whether the driver will.
