TOKYO Hitachi Ltd. has demonstrated prototypes of a hyrocarbon thin-film battery cell and portable fuel cartridges that it hopes will help direct methanol fuel cells (DMFC) replace current batteries.
The compact battery system was demonstrated recently at the Eco-Products 2003 show (Dec. 11-13), which promoted fuel cell cartridges as a convenient replacement for batteries.
Hitachi collaborated with Tokai Corp., a Tokyo based manufacturer of disposable cigarette lighters, to develop the cartridge, which operates without a mechanical system to deliver methanol fuel. The major lighter manufacturer provided its cartridge technology to supply methanol fuel automatically by an internal pressure without using a mechanical system.
The smallest cartridge is approximately the size of a AA battery, which snaps into a PDA. Hitachi researchers are shooting for eight hours of power from a 5-cc cartridge for portable devices.
The concentration of methanol is about 20 percent. But "our target is 30 to 40 percent concentration, which is dependent on the performance of the electrolytic film," a Hitachi spokesman said.
Hitachi has been developing an electrolytic film made from hydrocarbon on which nanoscale metal catalyst is formed. The catalyst also functions as an electrode. Since catalyst particles combine, Hitachi developed a technology that maintains the metal catalyst in nanoscale particles, preventing cohesion that would otherwise decrease surface area and performance.
Hitachi said it is aiming to complete DMFC technology development by 2005.