Yes, you can charge the animal camera with an external power supply. For the DC connection you need a 6V/1.5A adapter with 3.5mm (outside) and 1.3mm (inside) plug. 

Hello, please check if the rear camera is fully inserted into the dash cam main body. 

So when it powers off, it goes into a sleep mode. That sleep mode doesn't require alot of power, but if you have it set to turn on if the camera detects vibrations, it uses the cars battery. Mine is plugged in all the time and it only powers on when I turn the car on or it feels vibrations. With the vibration setting, it will turn on when I open my car door. But if your power source isn't powered when the car shuts off, then it doesn't use any power, just what the camera has stored up. Hope that helps 

The product itself has a battery capacity of 10400mAh, which is powered by solar panels. After fully charged before use, it does not need to be removed frequently for charging in summer and sunny places 

Yes, DC interface requires 6V/5A adapter, 3.5mm (outer diameter) 3mm (inner) plug.