Experts warn: 'Reliable standard testing and battery certification is needed for used electric cars'

Best charging habits to maintain battery health
“If you charge and discharge completely every time, you shorten the battery life,” says Philipp Vereken, an expert in battery technology at KU Leuven and Imec. “It is best to keep the battery, for example, between a minimum of 15 percent and a maximum of 80 percent and recharge within this margin as regularly as possible.”

Unlike petrol and diesel cars, a vehicle's residual value is not determined by its calendar age or mileage, but by the number of complete charge cycles. A charging cycle is the complete charging and discharging of the battery. If you charge the battery for the third time three times, this corresponds to one charging cycle.

“Never charge a battery to 100 percent and then not use that capacity right away,” recommends Luke Claessens. “Over time, this reduces the ability of the lithium in your battery to hold an electrical charge.”

It is also wise not to charge the battery too much at very low temperatures. “Modern electric cars first warm up the battery before starting the charging process. This is one reason why charging takes up to 50 percent longer at low temperatures.”

“Some electric cars can accelerate very quickly, but I would take it wisely because a heavy foot puts tremendous pressure on the batteries,” says Vereken.

Plugging your car into a fast charger wouldn't be a good thing either. “This was true until recently, but battery technology is evolving rapidly, and the latest ones are rarely affected by this,” Rylant confirms.