Operation of polymer electrolyte membrane fuel cells with dry feeds

Operation of polymer electrolyte membrane fuel cells (PEMFCs) with dry feeds is demonstrated to depend on the gas flow field design, gas pressure, temperature and flow rate. We demonstrate auto-humidified operation of the channel-less, self-draining fuel cell, from 25 to 115°C. Traditional serpentine flow channel designs cannot sustain autohumidified operation above 60°C. Auto-humidified (or self humidifying) PEMFC operation is improved in the channel-less fuel cell where axial dispersion enhances "back- mixing" of the product water with the dry feed. The auto-humidified self-draining fuel cell design offers substantial benefits for simplicity of operation and control including: the ability to self drain reducing flooding, the ability to uniformly disperse water removing current gradients and the ability to operate on dry feeds eliminating the need for humidifiers.