Earth Talk: Used electric vehicles

Dear EarthTalk: Is it true that you shouldn’t buy a used electric vehicle as the batteries only last 5-8 years and then require a costly replacement?

-- Paul, Boston

Answer: Many prospective EV buyers worry that the batteries in used EVs degrade quickly, requiring costly replacements. Understanding battery lifespan is crucial in deciding if a pre-owned EV is right for you.

Many studies, including one by Car and Driver, show that EV batteries can last "well beyond 100,000 miles, with many exceeding 200,000..." Modern lithium-ion batteries are built for durability, and they protect cells from extreme temperatures and overcharging. CleanTechnica highlights that “ordinary driving, rather than aggressive acceleration and braking, can extend EV battery life by reducing strain on the cells.” Also, avoiding deep discharges and extended high-voltage charging cycles helps preserve battery health. Most EVs can retain 70% to 90% of their original capacity even after years on the road. So, overall battery longevity is far more robust than many assume.

When considering a used EV, start by reviewing the battery’s state of health (SoH), which professional diagnostic tools or dealership scans can provide. Meridian Energy advises buyers to “check the battery’s health through the vehicle’s onboard diagnostics or by having an independent mechanic perform an inspection.” This report can reveal how much capacity remains and whether any issues have been flagged.

Climate also matters: Vehicles operated in extremely hot or cold regions may lose capacity faster. Consumer Reports recommends verifying if the original battery warranty still applies; many carmakers offer coverage for eight to 10 years or up to 100,000 miles, which often transfers to new owners. Also, certified pre-owned...