The battery slowly loses its charge when a vehicle sits idle – not least because the high-tech computers in today’s cars are always on, even when the engine is switched off. During the coronavirus lockdown, it should be enough to simply start the car every 3-4 days to prevent battery drain. If the vehicle will be left unused for any length of time, it can be a good idea to disconnect the cable at the negative battery terminal. The best approach varies depending on the make, model and year of the vehicle, so check the manufacturer's guidelines to be sure.
For EVs:beware of standby power drain
While electric vehicles (EVs) require much less maintenance than vehicles with internal combustion engines (ICEs), they are not entirely maintenance-free. Your electric vehicle can lose some of its range after sitting idle for just a week. It is important to keep your EV's battery at a proper state of charge. Most battery experts recommend keeping the charge at somewhere between 40% and 80% when the vehicle is left unused for a prolonged period.