Compact Direct Methanol Fuel Cell Power System Using Pulsed Electrical Control

There is an ever increasing demand for electrical power for individual soldier use. Presently, primary or secondary rechargeable batteries are utilized for field portable power devices; however, their energy capacity is insufficient to sustain the energy needs of an extended mission. Supplying replacement batteries presents a logistics burden, which could be alleviated with longer lifetime portable power devices. Lynntech is proposing to develop a compact and energy dense direct methanol PEM fuel cell system as an alternative portable power source. The proposed device utilizes pulsed electrical control in order to increase the average cell potential and allow operation at higher current densities. The purpose of the pulsed electrical control is to oxidize surface contaminants on the anode and restore high catalytic activity. Increasing the overall power density of the fuel cell stack will decrease the stack size, however, additional control electronics are required to facilitate the pulsed control scheme. Lynntech is proposing to compare two different pulse control strategies during this Phase I project: one utilizing short-duration, high current pulses generated by an externally powered circuit, and another that does not require any external power and utilizes only power from the fuel cell stack.