Study finds used EVs keep their charge: Kia leads on battery longevity, Tesla close behind
As demand for pre-owned electric cars climbs, fresh data out of Europe delivers good news for shoppers worried about battery life. In a large-scale assessment covering 723 battery-electric vehicles and 643 plug-in hybrids, nearly 80% of tested cars still held more than 90% of their original battery capacity after several years on the road. The results account for variables like driving mileage, age, climate, and typical charging behavior, offering one of the clearest looks yet at real-world battery durability.
The analysis used a three-star State of Health methodology from Swedish firm KVD to rate battery condition. Standout performers were brands with robust cell chemistry, effective thermal management, and smart energy control systems. Kia topped the charts for capacity retention across both its pure EVs, such as the EV6, and its plug-in hybrids like the Sportage. Another Kia model grabbed second place among individual vehicles, with the Tesla Model Y close behind. At a brand level, Tesla ranked second overall for battery health—especially noteworthy given the Model Y’s large sales volume in Europe, even as the market becomes more competitive with the rise of Chinese automakers.
Why this matters for buyers is simple: battery State of Health is becoming a primary metric in the used EV market, much like mileage and service history are for gasoline cars. With more reliable SoH ratings, shoppers can compare vehicles with greater confidence and predict long-term running costs more accurately.
Tips to maximize EV battery longevity, according to KVD’s experts:
– Keep daily charging between roughly 20% and 80%. Save 100% charges for just before long trips.
– Shield the battery from temperature extremes. Park in cooler spots during heat, and precondition while plugged in during cold weather.
– Fast-charge only when necessary. Avoid rapid charging a very cold battery and prioritize topping up at home before departing.
– Don’t store the car at 0% or 100% for long periods. If parking for more than two weeks, aim for about 40–60% and disable energy-hungry features.
– Set a charge limit in your vehicle’s software (for example, 80%), schedule charging to finish near departure, and keep software updated.
Warranties add another layer of confidence, but policies vary by region and brand. In Europe, Kia offers a seven-year or 150,000 km “boot-to-bonnet” warranty that includes the battery and drivetrain. Tesla’s basic vehicle coverage is four years or 80,000 km, with an eight-year battery warranty. In the United States, Kia’s battery coverage extends to ten years, a benchmark for the industry. Both brands currently guarantee at least 70% battery capacity retention over the warranty period.
Meanwhile, Chinese manufacturers are pushing the envelope with efforts to standardize longer battery warranties—some targeting 15 years with 85% capacity retention. The world’s largest cell maker, CATL, already supports extended coverage windows, including 12-year warranties for certain battery swap applications and up to 20 years for some LFP energy storage systems, signaling that the underlying chemistry is ready for longer service life.
Recyclers echo the trend. The largest EV battery recycler in the United States has estimated today’s EV packs can realistically last 15 years or more. That aligns with the European study’s positive findings and suggests official warranty terms may have room to grow. Extending warranties would further accelerate confidence in used EVs, making the second-hand market as vibrant and trusted as the one for combustion cars.
Bottom line: Most used electric vehicles retain the vast majority of their original battery capacity, with Kia setting the pace and Tesla close behind. Shoppers should look closely at State of Health ratings, follow smart charging habits, and weigh warranty terms carefully. With durable packs and improving support from manufacturers, buying a used EV is looking smarter than ever.
