How to charge your electric car properly to protect the battery

The battery is the most expensive part of an electric car, and the way you charge it matters in the long run. The good news is that the rules are few and easy to remember.

Day to day, don’t charge to 100%

Lithium-ion batteries age faster when they sit for long periods very full or very empty. For everyday driving, many manufacturers recommend a charge limit of around 80%, which you set in the car or the app. Charge to 100% before a long trip and set off soon after.

Don’t leave the battery empty

Dropping to 10% now and then is not a problem. Leaving the car for days close to 0% is. If you are away for a while and the car stays parked, leave it at around 50%.

Fast charging: when you need it, not out of habit

DC fast charging is designed for long trips and is safe for the battery, especially on cars with active cooling. Used every day, particularly in summer, it can speed up wear. Above about 80% the power drops sharply anyway, so on a trip it is more efficient to charge several times to 70–80% than once to 100%.

Winter and summer

• In winter, charge right after a drive while the battery is warm, or use preconditioning before a fast charger. A cold battery charges more slowly.
• In summer, park in the shade when you can and avoid leaving the car at 100% in the sun.
• Turn on heating or air conditioning while the car is plugged in, so the energy comes from the grid, not the battery.

What it means for hybrids

On a full hybrid you don’t control charging: the computer keeps the battery in a middle band. What you can do is look after the cooling. On many Toyota and Lexus models, the battery filter and fan clog with dust and the battery overheats. See hybrid battery cooling.

More on how long charging takes in how long it takes to charge an EV, and on home installation in our guide to the home charger.