Nice project! I hope the battery will start work with the inverter.
Did you check the firmware compatibility between the inverter and the battery?
I have some experience hacking CAN bus battery interfaces, but this is probably MODBUS RTU. I am curious whether the battery or inverter is the master device? If you have some bus logs, we can discuss them here.
I will follow up with interest the repository about the reverse engineering process. I'm running an inverter with a custom HV battery and planning to update my BMS solution. So I will be happy to see how the BYD battery is made .