Both companies say they are working on fuel cells that can turn methanol directly into electricity and could have many times the capacity of current lithium-ion batteries. Although the basic physics is not new, both companies are turning to nanotechnology to overcome some of the issues that have thus far prevented fuel cells from becoming commercial products.
The basic innovation is the use of forms of carbon called fullerenes, in which the atoms form geometric meshes that can be molded into different shapes.
NEC has developed its design in conjunction with the Japan Science and Technology Corporation and the Institute of Research and Innovation. It uses nanohorns, fullerene sheets rolled into microscopic cones, incorporating platinum atoms to catalyze the electrochemical reaction that rips methanol apart. Such cells are around 20 percent more efficient than existing fuel cells, NEC asserts, and can offer 10 times more power per weight than lithium-ion at a comparable cost.
The company predicts this could give mobile phones and laptops many weeks of operation between recharging. NEC expects to be in production between 2003 and 2005.
Sony has yet to say when it expects to commercialize its technology, which uses a similar complex carbon structure. Unlike earlier designs that required high temperatures to work, the company said, electrodes using fullerenes are effective for the range of temperatures encountered by personal portable devices. They also exhibit a far smaller lag between demand and supply; while other fuel cells take many seconds to generate power, fullerene technology kicks in within one to two seconds.
Both companies have yet to sort out practical issues such as the recharging mechanism. Unlike current batteries, fuel cells are replenished by injecting fresh methanol.
Staff writer Rupert Goodwins reported from London.