NTT DoCoMo is showing at this week\u2019s Ceatec show in Japan a prototype fuel cell that it\u2019s developing with a Japanese startup for use as a cell-phone recharger.The polymer electrolyte fuel cell (PEFC) uses hydrogen gas as a fuel to produce electricity, is a compact 24 millimeters square and 70 millimeters\u00a0long, and weighs 45 grams.\n\n\n\n\n\n\n\n\n\nCeatec EntranceThe fuel cell is under development by Aquafairy, a startup spun out of Nitto Denko to work on the technology. NTT DoCoMo recently acquired a 36.5 percent stake in the company for an undisclosed sum.The fuel cell can deliver enough power to recharge a cell phone three times before requiring a hydrogen refill.While it\u2019s still some way from being a commercial product, the fuel cell is completely different\u00a0from what NTT DoCoMo showed at Ceatec 2005. A year ago, the company was displaying a direct methanol fuel cell (DMFC) that was developed by Fujitsu Laboratories and built into a cradle, into which a cell phone could be placed for recharging.DMFCs are based on a different chemistry from the PEFC on show this year. They typically work by mixing methanol with air and water to produce electrical power.\n\n\n\n\n\n\n\n\n\nDoCoMo Fuel CellsFor companies like NTT DoCoMo, a future goal remains a fuel cell small enough and safe enough to be built directly into a cell phone. But the technology isn\u2019t at that stage yet, so the first commercial fuel cell devices will likely be rechargers that replenish the Lithium Ion battery inside of the phone but offer the advantage of being able to do so anywhere\u2014not just within a couple of meters of a wall socket.-Martyn Williams, IDG News Service (Tokyo Bureau)Related Links:\n\nReplacement for Lithium-Ion Batteries Debuts\n\nApple, Dell Plot Battery Standards\n\nPC Vendors Blame Batteries, Not Notebook DesignCheck out our CIO News Alerts and Tech Informer pages for more updated news coverage.