bvgandhi via EV <ev@lists.evdl.org> wrote: >> For a BMS of a large battery pack for an automotive application can >> I have all my slave boards connected to the cells and part of the >> pack and a master controller outside the battery pack where I can >> integrate some other control functionality as well?
Cor van de Water via EV wrote:
Sure, as long as the communication to the slave boards is isolated, preferably on the slave board itself. That way you just bring 12v plus communication bus to each slave. Almost every commercial bms works this way. OEM bms typically uses CAN bus.
I took a slightly different approach in my BMS. I route a (fused) wire from each cell "+" terminal to a cental relay board. The relay board selects two wires (the + and - of the cell to be monitored), and routes them to a central controller. The controller has the optical isolation. That way, only *one* isolator is needed, rather than one per cell.
This is how the Toyota Prius BMS works as well. Just a thin wire from each cell to the central BMS board. The isolation is done on the central board.
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