I've designed a few boards that use LiPoly batteries with the Microchip MCP73833 charger chip. It seems to work well in singles, but I haven't been brave enough to run a few in series for some 12V motors.
My first thought was to have an MCP73833 for each LiPoly cell. The Vin sides would be in parallel and the Vout sides would be in series. However, as soon as I drew that out in my head, it became clear that it would end up all explody due to the common ground on one side and non-common round on the other.
I need to switch the whole system between parallel and series, grounds included. I could certainly do it with some relays or multi-pole switches, but automatic would be cool.
It's been on the back burner for a while, but I've got some pretty good small 12V motors that I want to use. The search for a non-explosive solution is back on.
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