Your vehicle doesn't truly sleep when you lock it.

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It's already costly enough to leave your EV at the airport for a week without it quietly discharging electricity while you're away. You could end up with a reduced battery percentage, even if the odometer hasn't budged. The truth is that an EV will lose a bit of charge while it's parked, but the amount lost will vary depending on the EV and what it has been doing while you were away.

There are a lot of factors involved when it comes to EV energy loss. Lithium-ion cells can lose charge naturally through electrolyte oxidation and reduction via a process called self-discharge. However, that is negligible compared with the electricity used while driving. The larger loss is from systems that continue to operate after you've locked the doors.…