Hi, I need to charge lithium batteries (3 to 12 cell packs) and prevent individual cells from exceeding the desired voltage (4.2v each). This is most commonly done in hobby circles using a charger that takes the overall pack up to the desired total voltage (eg: 12.6v for 3 cells) and a separate balancer circuit to try to keep each cell the same.
What I would prefer is a charger than can charge each cell individually to 4.2v and eliminate the need for the balancer circuit. Single cell lithium charging chips are readily available, and if I were to supply each of these from separate 5v mains power supplies I could daisy chain any number together and achieve my objectives. An example of what I mean is shown in this post if I'm not clear:
However, I would like to do this from a single 12v car battery source. So I need a step-down design with up to 12 isolated outputs (~5V each). I need at least 3A each, preferably more. Does anyone know of a elegant way of achieving this please? Thanks, David.