BQ76PL455EVM-GUI-SW: BQ76PL455EVM

Tool/software:

Hi Dear, 

Currently, we are currently designing a solution to charge and discharge a battery module using the BQ76PL455EVM and an external charger/load, to charge and discharge respectively. 

From our side, we have the next picture about the BQ76PL455EVM and some doubts & clarifications has appeared. Considering the BQ76PL455EVM allow to monitor the voltages and temperatures from the battery pack, but also the passive balancing functionality:

1. In the scenario where a charge/discharge cycle is being performed, is the BQ76PL455EVM  really capable of working autonomously to balance each cells (considering each voltage cell value) or is it really needed a master uC to manage it?
2. We have performed a test to charge the battery pack and the passive balancing is already activated in the 7 cells (pack 7s1p). So, we have the next results:
   1. Step 1: battery is not charging (only BMS + Battery module connected). Here one of the cells has a greater value than the others.
   2. Step 2: charging process. In this phase, we have expected that the purple voltage line (cell voltage N) converges with the other cell voltage lines, but the behaviour is the opposed. Thi is due to all cells have activated the passive balancing functionality? This should be managed by a master uC to only activate the passive balancing of the cell that has the maximum voltage value or the BQ76PL455EVM works autonomously when the balancing is activated in all cells?

Thanks in advace for the information. 

Br, 

Jeff