Looking after a hybrid battery

Hybrid batteries usually outlast the car, if they can keep cool. Three habits that help, and when to have the battery checked.

Most hybrid and electric car batteries now last well past 150,000 miles. What shortens their life is heat, and long spells sitting at full or empty.

Keep the cooling vent clear. Many hybrids cool the battery with air from the cabin through a vent near the back seat. Bags and coats over it make the battery run hot.
Don’t leave it at 100% for days. On a plug-in, set the charge limit to 80% for everyday driving, and charge to full before a long trip.
Drive it. A car left for weeks lets the 12-volt battery go flat, and the big battery can’t start the car without it.

A battery health check takes about an hour and shows the state of every cell block. It’s worth doing every two years, and always before you buy a used hybrid or EV.