[slantyyz]

I'm more curious how that built in LiOn battery would stay charged while parked outside for a full work day on a super cold day in winter, when decent sunlight is scarce. Has it been tested in a place where temperatures can dip to -20C / -40C with wind chill?

[Johnny555]

The camera stays in low power mode (polling with BLE?) until woken up by the OBD controller to tell it that the car is in reverse. It doesn't need much power to stay charged.

[rcthompson]

I don't think it's a question of energy use, it's a question of whether the battery can hold a charge under those conditions.