This Small Business Innovation Research (SBIR) Phase II project will develop a zinc-air fuel cell for replacement of internal combustion engines in polar and other cold climates. Phase I examined the electrochemistry of the zinc-air fuel cell's anode, cathode, electrolyte, and system designs to identify and optimize critical low-temperature performance characteristics. This power source has inherently high energy- and power-density as well as exceptional reliability at start-up temperatures as low as -40 degrees Centigrade. Phase II will develop 500-watt prototypes, capable of internal and external recharging, for low-temperature, low-maintenance remote use.<br/><br/>Potential commercial applications include portable rechargeable power supplies, materials handling equipment, personal mobility vehicles, and cellular telephones operated in polar and other cold regions.