Abstract: A battery cooling system 10 for use with a vehicle 14 including several batteries or battery modules 16-38 which provide power to the vehicle 12. The system 10 includes a refrigerant gas channeling or conduit system which is effective to store, compress, expand and circulate refrigerant gas through the battery pack 12 and the system 10. A first “high pressure” conduit system, having several tubes or conduits that are disposed throughout the vehicle 14, is used to selectively carry and transport pressurized or compressed refrigerant gas to the battery pack 12 and includes a pump 42, a heat exchanger 44, expansion valves 46-52, and conduits 54, 56, 58, 60 and 62. A second “low pressure” conduit system is used to circulate the “expanded” or decompressed refrigerant gas throughout the battery pack 12 and to return the refrigerant gas to pump 42 for recompression.