New fuel cell promises five times the energy density of Direct Methanol Fuel Cells
By Mike Hanlon
April 27, 2006
April 28, 2006 Maxell Hitachi has announced a new variation on the Polymer Electrolyte Fuel Cell (PEFC) which uses water and aluminium to generate hydrogen and promises a low cost 10 watt cell (enough to operate a laptop PC) with five times the energy density of Direct Methanol Fuel Cells (DMFC). With mobile devices becoming ever more compact, there is an increasing urgency to create higher density power sources. Without question, fuel cells will provide the answer, but both DMFC cells which use methanol as fuel and PEFC cells which use hydrogen as fuel, have their drawbacks. The limiting factor for DMFC is a low power density and problems* with the methanol crossover, while for PEFC the complex equipment, high-pressure tank and high cost of the reformer are the limiting factors. Maxell’s new variation of the PEFC generates hydrogen from the reaction of aluminium and water and promises a simple and low cost system suitable for application in fuel cell power sources up to 100W.
Building on the work of Professor Masao Watanabe of the Muroran Institute of Technology, Maxell has further improved the hydrogen generation process and developed a new aluminium particulate conversion process to the point where it can generate 1.3 litres of hydrogen for each gram of aluminium. The company envisages that continuous, long term power output suitable for a laptop PC or emergency power would be available by exchanging cartridges (containing the aluminum and water),
In addition Maxell has developed a membrane-electrode assembly (MEA), one of key components of fuel cells, with a power density of 280mW/cm2 at room temperature.
* With the phenomenon where methanol passes a polymer electrolyte membrane, it becomes not only fuel loss, but cause of low voltage and heat generation which depend upon the oxidation reaction of transmitted methanol.