BMS Build Log: vehicle edition
So far I've converted, or helped convert several electric vehicles but I haven't actually built a proper battery monitoring/balancing system. That changes now!
* Isolated modules - target pack voltage is 330V, 100-series LiFePo4
* Multi-drop bus - CANBUS because it's the ubiquitous industry standard in most vehicles
* Very low quiescent power draw - the BMS shouldn't be the cause of significant cell imbalance
* Balancing - extra energy in weaker cells is dumped near 100% SOC to correct for drift between cells
Version 1 has a couple major flaws, but I'm able to interact with the bq76930, read cell voltages, and enable the balancing circuits. RevB will fix some missing traces and rearrange how the Propeller and CAN transciever are powered.
I'm going to go ahead and make this an open-source, open-hardware project.