Dynamic battery system voltage control through mixed dynamic series and parallel cell connections

摘要

An electrified powertrain for a vehicle includes a battery system configured to switch individual battery modules between series, parallel, and bypassed connections, thereby eliminating the need for a DC-DC converter. The battery system is also configured to generate (via a set of drive switches) AC voltages for an electric motor, thereby eliminating the need for an inverter. Control methods for the electrified powertrain, which could be implemented in a controller of the vehicle, include controlling the switches of the battery system to maintain a constant desired output voltage during both discharging and recharging. The control methods also include controlling the series, parallel, and/or bypass switches of the battery system to bypass malfunctioning battery modules and/or to decrease the output voltage of the battery system below a voltage threshold that requires electrical isolation.