The most important information an electric vehicle buyer can have is the condition of its battery.

So Autotrader is bringing that information to its EV listings.

The Cox Automotive brand announced it will make EV battery health scores available on its used electric vehicle listings, aiming to give shoppers “a fuller picture” of the battery’s performance and usable range before they buy.

“Used EVs are the best kept secret in car buying, as they offer cost savings, energy efficiency, government incentives, newer technology and more,” Autotrader executive editor Brian Moody said in a news release. “Before you buy, make sure you have information on the vehicle’s battery health.

“Just like your mobile phone or laptop battery, EV batteries can degrade over time, so understanding its performance and how it was cared for will help drivers understand when or if a used EV’s battery needs to be replaced.”

The U.S. Department of Energy’s National Renewable Energy Laboratory determined modern EV batteries will last 12-15 years in moderate climates, covering 100,000-200,000 miles.

They can last even longer depending on how well they are maintained, Cox said in a news release, and offered recommendations for keeping as EV battery’s in “top condition.”

Optimal charging practices: Charging habits matter. Keeping the battery above 20% and below 80% of charge is vital to helping protect electric car battery longevity, the company said.

Maintain battery temperature: Temperatures affect battery performance, EV range and longevity. Automakers also suggest owners plug in their vehicles if they are away for an extended period.

Software updates: While an EV doesn’t need an oil change, it does require over-the-air updates, including those for the battery management system, to keep the vehicle working properly.

Monitor battery health: Watch for warning signs such as slower charging times, decreased range or inconsistent power delivery, that point to the need for a battery check, and have it inspected by a professional if needed.

Avoid repeated acceleration: While speeding up quickly or repeatedly using the “boost” button in EVs is tempting, it can consume more power from the battery and wear it down faster. Gentle acceleration is best.