ENERGY TRANSFER AMONG MISMATCHED BATTERY SYSTEMS

An energy transfer system includes a conversion device configured for partial power processing and configured to regulate current from a first battery system, and a controller configured to control the conversion device to adjust a first voltage of the first battery system to conform the first voltage to a second voltage of a second battery system, the second battery system connected in parallel with the first battery system by a bus. The conversion device is configured to receive power from the first battery system, cause a selected portion of the power to flow through a conversion stage to adjust the first voltage, the selected portion corresponding to a difference between the first voltage and the second voltage, cause a remaining portion of the power to flow directly to the bus and bypass the conversion stage, and output a current from the conversion device at the second voltage.