A used electric car: the battery is half the purchase price

An electric drivetrain has a fraction of the moving parts of a combustion engine. There is no clutch, no cambelt, no exhaust, no particulate filter and essentially no oil change. Even the brakes last longer because much of the deceleration goes through the motor — which does mean the discs are more likely to rust than to wear out.

What remains is the battery. It is the most expensive component in the car, and its condition determines range, charging behaviour and resale value all at once.

Remaining capacity can be read out — depending on the maker, through the car's menu, through the app or at a franchised garage. Ask to see the report, not the range display: that shows an estimate from the last driving profile and says nothing about the state of the battery.

Also ask about the battery warranty. With most makers it runs longer than the vehicle warranty and guarantees a minimum capacity over a set period or mileage. What counts are that maker's specific terms — general claims are of no help here.

Two cars with the same battery size can be entirely different propositions on a long journey. What matters is the power at which they charge and how long they hold it. A car that charges at fifty kilowatts stands at the charger twice as long as one at a hundred and fifty — with the same range.

In winter the range drops because the car must be heated and a cold battery gives less. A heat pump softens that considerably and is an option worth asking about on a used car — on many models it cost extra.

The second point is mundane and still gets overlooked: work out where you will charge before you buy. An electric car with no fixed charging point at home or at work is far less convenient day to day, and public charging costs several times the domestic rate.