Fujitsu Triples Charging Capacity of Fuel Cells for Mobile Phones

Tokyo, July 6, 2005 Fujitsu today announced its co-development with NTT DoCoMo of a prototype high-capacity micro fuel cell and the prototype development of an external recharger for FOMA handsets. For the prototype micro fuel cell device, the concentration of the methanol fuel used was raised from 30%, the concentration used for the companies' previous fuel cells, to a remarkably higher concentration of over 99%. This enables the prototype device to charge up to three FOMA handset batteries with just 18 cc of methanol.

The jointly developed fuel cell prototype will be exhibited at Wireless Japan 2005 to be held from July13 to 15, and at the Environment corner at Fujitsu Forum 2005 from July 14 to 15, both in Tokyo.

Development Background

The R&D of micro fuel cells with replaceable fuel cartridges is being conducted, with the purpose of extending the operation time of mobile devices such as mobile phones. In comparison with conventional lithium ion batteries, micro fuel cells offer theoretical performance that is ten-fold, and are capable of high-density storage of energy at practical performance levels three times greater.

In addition, since micro fuel cells can use methanol derived from biomass resources, there is anticipation that they will help reduce burden on the environment.

The performance of micro fuel cells depends on how compact they can be made and how much energy can be created from a given volume of fuel. Higher-capacity micro fuel cells will significantly improve user convenience, such as by increasing the number of times recharging is possible with a single cartridge.

Technological Challenges

Since micro fuel cells that employ methanol produce energy through the reaction between methanol and oxygen present in the air, power capacity can be increased by raising the concentration of the methanol solution. However, for passive type fuel cells that are suited for miniaturization and lighter weight, a phenomenon known as "methanol crossover" occurred, which is a fuel permeation that occurs between battery electrodes when high-concentration fuel is used directly with passive fuel cells, thereby resulting in lower generation efficiency.

Newly Developed Technology

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