[Sergio]

Most folks build a single pack (single BMS) with multiple cells in parallel if more capacity is needed.

Since the cells in the Chevy pack cannot be taken apart, You need two BMS, one for each pack to balance and provide cell monitoring for that pack.

When the packs are connected together, it creates a problem for a single pack to stop either charge or discharge.

My suggestion fixes the charge problem, but you need to be careful on the discharge side and don't run the packs too low.