The BYD Battery-Box is a lithium battery with battery control unit (BCU) for usage with an external inverter. 

Battery Control Unit (BCU)

The BYD Battery Control Unit consists of the B-Box base, cover, BCU and wall-mounting bracket. It can accept 2, 3 or 4 BYD B-Plus H 2.5 lithium iron phosphate (LiFePO4) battery modules.

The flexible battery system provides maximum safety, lifetime and performance, which makes it the perfect battery for all applications.

The Battery-Box HV is the first real high voltage battery that comes with a flexible and modular design with no cables inside. One Battery-Box HV contains 2 to 4 battery modules B-Plus H 2.5 in series connection and reaches up to 10.2 kWh usable capacity.

• B-Box H5.0 (5.12 kWh): 2 battery modules
• B-Box H7.5 (7.68 kWh): 3 battery modules
• B-Box H10.0 (10.24 kWh): 4 battery modules

• 	Battery Box H5.0	Battery Box H7.5
  Battery Module (B-Plus-H 2.5 - 2.56kWh):	2 Modules	3 Modules	4 Modules
  Usable Energy:	5.12 kWh	7.68 kWh	10.24 kWh
  Max. Output Power:	5.12 kW	7.68 kW	10.24 kW
  Peak Output Power:	7.17 kW, 10 s	10.75 kW, 10 s	14.34 kW, 10 s
  Round-Trip Efficiency:	>95.3%	>95.3%	>95.3%
  Operating Voltage Range:	204 V	307 V	409 V
  Operating Voltage Range:	160 - 225 V	240 - 338 V	320 - 451 V