I've got a robot that I use two batteries on. One of the batteries power the servos and engines and the other is for the digital boards.
- The servos need 5 V.
- The control board and LCD run on 5 V.
- The engines use 12 V.
Both batteries are identical 12 V packs (3x 18650) each with their own BMS.
The robot is using DC-DC 12 V to 5 V step down converters to get appropriate voltages to the different parts.
I want to be able to charge both batteries from one 12 V source but also keep them isolated so the motors battery cant take juice of the digital battery and vice versa.
Can I use diodes on the 4 lines (2+, 2 Ground) coming from the single charger two for each battery to accomplish this separation?
Should I put a diode on each side of each battery or for example only on the ground or volt?
Is there a better way?
The lines between the Arduino and the controller don't link the batteries in any way. But the common charged does which is the problem I want to solve.