I have 3, 7s96p battery boxes, each about the size of a car battery.
I am currently using a chineesium BMS that scares me a little, it’s configured 7s, i.e the 3 battery boxes are in parallel effectively 7s288p, with the balance leads in parallel as well. This means i am balancing 288 cells 
, I would prefer to balance 96 cells i.e. per battery box, is this the right thing to do ?
I can replicate the above BMS with 7 DIYBMSV4 boards and a controller, easy…BUT…to get more info (and to reduce the number of cells balancing per board) I would like to use 21 boards (7 per battery box).
I may be confusing myself so can anyone help me get my head around this ? Is this 3 banks in the software setup (with 7 boards in each), or 3 banks (2 with 10 boards and a 3rd with one board) ?
Any help, criticism, etc very welcome
Keith