Actively-switched direct refrigerant battery cooling

A vehicle comprising:

• a transmission;
• an electric traction motor connected to the transmission and operable for delivering motor torque to the transmission;
• a battery pack electrically connected to the electric traction motor and having a conductive cooling plate and plurality of battery cells, wherein each of the plurality of battery cells is in thermal communication with the conductive cooling plate;
• and
• a thermal management system comprising:
• a compressor operable for circulating refrigerant through the cooling plate to cool the battery cells;
• a plurality of flow control valves in fluid communication with the compressor;
• a temperature sensor configured to measure a temperature of the battery pack;
• and
• a controller in communication with the temperature sensor and with the plurality of flow control valves, wherein the controller is programmed to receive the measured temperature and selectively transmit switching control signals to the plurality of flow control valves to command a change in direction or concentration of flow of the refrigerant through the conductive cooling plate, and to thereby limit a temperature variance between the battery cells over time.

A method of controlling a thermal management system for a battery pack having a plurality of battery cells in thermal communication with a conductive cooling plate, the method comprising:

• receiving a temperature of the battery pack from a temperature sensor, via a controller, while refrigerant is circulated through the conductive cooling plate via a compressor;
• selectively transmitting switching control signals via the controller to a plurality of flow control valves positioned between the compressor and the battery pack in response to the received temperature;
• and
• controlling a direction or concentration of flow of refrigerant through the conductive cooling plate via the plurality of flow control valves in response to the switching control signals, thereby limiting a temperature variance between the battery cells over time.