Battery Power for Dash Cams and Parking Mode

Most cannot record a normal journey that way. The internal cell, where fitted, is generally for short operation or safe file closure; use the specified external supply.

It can if power is unmanaged. Use a compatible low-voltage cut-off or dedicated battery and follow the camera and vehicle instructions.

No. A supercapacitor stores enough energy for tasks such as closing a file safely, but it is not intended as long-duration recording power.

It charges while the vehicle is running and supplies the camera after the ignition is off, reducing reliance on the starter battery during parking recording.

Only if the camera maker explicitly supports that arrangement. Ordinary consumer power banks may not suit vehicle heat, charging behaviour or unattended use.