Is it possible to charge a battery with another battery? E.g. Battery A (30Q) charged by Battery B (30Q). How do you control and make sure that Battery B charges Battery A and not the other way around?
The idea is, I have a 10s4p on the board. I want to be able to carry a battery pack in my bag for emergency charging, a 10s2p that I can plug to the charging port of the board. Is there something I need to do to make sure that the emergency battery charges the pack on the board and not the other way around?