I guess this it has a battery inside plus a board to reduce from 12VDC to 9/5VDC. Do you see the 12VDC port has 2 ways in/out that the 12VDC adapter along as the photo. Hence it is unlike as a battery bank 10,000mAh so let pick battery bank if using for Pi or any device needs 5VDC looks better due to compact, simple
... even the batter bank it is not a pure linear power
