By Pedro Junceiro
A study conducted by Generational+, a British company specializing in battery testing for electric vehicles, concludes that these batteries resist degradation much better than expected. This type of analysis is fundamental to support the used market, due to the impact that this factor, always greatly feared by consumers, has on the residual values of vehicles.
In fact, batteries, the most expensive component in electric vehicles, continue to be viewed with suspicion by many drivers, who fear substantial losses of their respective capacities with age and use. This concern is reflected in the used market and in the residual values of customers from large fleets, who fear significant devaluations in car prices based precisely on the stigma we described at the beginning of this paragraph.
However, the study by Generational+ presents much more positive conclusions: “Batteries are performing better and degrading less than we all expected”. Emphasizing the need for a different approach to the depreciation criteria for used electric vehicles, since the principles of age and mileage adopted for combustion engine cars do not fully adapt to electric vehicles, the British company states that it is the state of the battery that allows for defining the value of a used electric vehicle, as it “represents a stable basis for well-informed decisions”.
The company studied more than 8000 electric vehicles, including light passenger and light commercial vehicles, with different ages and mileages. “The results confirm that the overall performance of the batteries significantly exceeds the expectations of both manufacturers and consumers, although the results depend heavily on the use of the vehicles”.
The State of Health of the battery is a metric used to describe the condition of this component in relation to its original capacity and allows for an understanding of both usage and estimated lifespan. This is essential for consumer confidence and obtaining warranties. The convention in the industry is that a battery with a capacity below 70% is at the end of its life but can be used for other types of secondary applications (Second Life).
“In all vehicles tested in 2025, the average battery health stood at a robust 95.15%. Even in cars that are eight or nine years old, the batteries maintain average capacities around 85%, comfortably above the 70% threshold that triggers warranties for most original equipment manufacturers,” concludes the study. It adds: “Even vehicles with high mileage – over 100,000 miles [about 160,000 km] – often show results between 88% and 95%. Therefore, mileage alone is not the most reliable indicator of battery condition. However, results vary from brand to brand and model to model. That is why these tests are so important,” it explains.
Finally, according to Generational+, the degradation of batteries is much slower than expected, sitting, in the worst-case scenario, at 82% Battery State of Health for vehicles aged between eight and twelve years. The British also conclude that charging habits are crucial for battery longevity, thus recommending the maintenance of good practices.
