Fuel cells get small enough to power hand-held electronics
Toshiba announced that Guinness World Records certified its compact direct methanol fuel cell (DMFC), with 100 milliwatts power output, as the world's smallest DMFC.
Tiny methane-based fuel cells like this one from Toshiba could make instrumentation even more mobile and distributed.
Toshiba announced that Guinness World Records certified its compact direct methanol fuel cell (DMFC), with 100 milliwatts power output, as the world's smallest DMFC. The record will appear in the 2006 edition of the Guinness Book of World Records. Toshiba's DMFC is only as long and wide as a thumb, offering greater design freedom for developers of handheld electronic devices. At 22 x 56 x 4.5 mm (9.1 mm with fuel tank), the prototype powers an MP3 music player for as long as 20 hours on one 2-cc charge of 99.5% concentration methanol. Weight is 8.5 g (0.3 oz) with fuel.
Passive DMFC have no pump or fan, reducing system size and complexity. They’re called “direct” because DMFCs (both active and passive) use methanol as fuel and do not change its chemical structure by subtracting hydrogen when feeding fuel into the cell, thus sending methanol "directly" into the cell.
Limited 2005 commercial availability is expected, subject, in part, to certain regulations related to use of methanol, the company suggested. Toshiba is working with organizations and regulatory bodies. Regarding safety, the company said, “Compared to batteries, we expect better safety performance under abnormal conditions such as external shorts, overcharge, or overload, since the energy is not stored in the fuel cell while batteries hold readily available energy inside.” The International Electrotechnical Commission (IEC) has a TC105 fuel cell technical committee working on industrial standards: WG 8, 9, and 10, for safety, performance, and interchangeability, respectively.
Toshiba says it has more than 110 patents on DMFC technology. In March 2003, Toshiba announced a larger prototype for a Toshiba Libretto mini-notebook PC; a 100-cc cartridge runs that device for 10 hours.
—Mark T. Hoske, editor-in-chief, Control Engineering, MHoske@cfemedia.com