Fujitsu triples the charge on a micro fuel cell

 

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By Steve Malone

Posted on 7 Jul 2005 at 11:37

The prospect of fuel cell technology for powering small devices has come one step closer. Japanese electronics giant Fujitsu says it has tripled the charging capacity of fuel cells for mobiles and has now developed a commercial prototype with the Japanese telco DoCoMo.

Fuel cells are not only rechargeable but also environmentally friendly. Unlike traditional devices that are based on lithium and have to be thrown away when exhausted, fuel cells run on methanol that produces only water as a waste product and can be refilled. However, R&D departments have tried for many years to get sufficient power from a fuel cell device to make it marketable.

In order to raise the charge held by the cell, Fujitsu managed to raise the concentration of the methanol fuel from 30 per cent, the concentration used for the companies' previous fuel cells, to over 99 per cent. As a result, the prototype device can charge up to three FOMA handset batteries with just 18cc of methanol.

Major Japanese and US companies have been pouring into fuel cell research for many years. However, one of the problems in creating a commercially viable design for use in small devices has been 'methanol crossover'. Fuel cells work by reacting methanol and oxygen to create an electrical charge. However, a problem arises when the concentration of methanol becomes too large and the fuel permeates the battery electrodes and decreases the efficiency of the cell.

Fujitsu says that it has developed a new material that reduces the methanol crossover effect by 50 per cent compared to previous materials it has tried and to only 5 per cent of that of other commercially available materials. By using the water by-product to dilute the fuel, the design limits the loss of efficiency when using high-concentrations of methanol.

Pictured is a prototype micro fuel cell recharger and FOMA handset shown separately