Hitachi and Toshiba have unveiled new fuel cell prototypes for a range of applications that could be commercialised as early as next year.
The prototypes on display at Ceatec Japan 2004 in Chiba show that fuel cells could become a widely adopted supplementary power source to conventional lithium ion batteries, and could start replacing them in some applications after 2007, according to developers.
As well as showing its prototype fuel cell for personal digital assistants (PDAs) that it announced last December, Hitachi also unveiled a prototype laptop PC fuel cell and a fuel cell-based battery recharger for mobile phones, both of which will be available in 2006, according to the company.
In addition, Hitachi would make a lithium ion battery replacement fuel cell that it will put on sale in 2007, senior engineer of Hitachi's fuel cell promotion and development group, Mitsugu Nakabaru, said.
All of the prototypes use direct methanol fuel cell (DMFC) technology.
The demonstration model PC fuel cell shown is designed to latch on the back of a laptop screen, and is about 25cm wide, 20cm long and between 1cm and 2cm thick. This includes a cartridge containing methanol that is diluted to a 20 per cent to 30 per cent concentration to produce power in the fuel cell.
Hitachi was not disclosing the exact specifications, but the demonstration model weighs under one kilogram, said Nakabaru.
The prototype was designed to provide at least five hours of continuous operation for even the most power-hungry laptops while they were running multiple applications, Nakabaru said.
"Five hours, we think, is the minimum specification customers will accept, but we think it will provide five to seven hours at 10 watts for most laptops running the usual programs," he said.
The laptop version is nearly ready for commercialisation, but Hitachi was working to improve specifications, including developing the fuel cell's capability to use higher concentrations of methanol up to 40 per cent, Nakabaru said.
The company declined to discuss potential prices.
"It's nearly ready," Nakabaru said.
Hitachi's fuel cell for PDAs, which the company already announced, was on target for sale in the second half of 2005, he said. That prototype fuel cell wass a cartridge type about 1cm in diameter and between 5cm and 6cm in length.
Specifications for the commercial model were about the same, he said.
Both Hitachi and Toshiba are showing prototype fuel cell-based lithium-ion battery supplementary power sources for mobile phones designed for KDDI, Japan's number-two carrier.
The number of major Japanese electronics companies that have announced fuel cell rechargers for this application currently stands at three. Last week, NTT DoCoMo and Fujitsu Laboratories said they developed a prototype DMFC technology recharger for commercialization in 2006.
That version is a cradle-type design that uses a thumb-sized cartridge containing 18cubic centimetres of methanol at a concentration of 30 per cent to provide an output of 5.4 volts at 700 milliamperes. The commercial version will be able to provide enough power to charge a lithium ion battery three times, to provide about 6-hours worth of continuous use, according to NTT DoCoMo.
The Hitachi and Toshiba prototypes are standalone boxes with cords that plug into KDDI mobile phones.
Both designs wwouldbe available before the end of March 2006, Youichi Iriuchijima, assistant manager of KDDI's IT development division, said. Hitachi's fuel cell recharger was smaller than Toshiba's, but Toshiba's design wouldprovide power for longer, Iriuchijima said.
The companies are not releasing details about size and weight, and the demonstration models were displayed under plastic. The Hitachi prototype appeared to be about 10cm long and less than 5cm wide, while the Toshiba version appeared to be about 10cm square.
The Hitachi version uses 46 per cent methanol concentration fuel to provide 700 milliwatts and 3.5 volts, that was capable of providing at least five hours of supplemental power when a lithium ion battery was exhausted, Iriuchijima said.
The Toshiba prototype used a 100 percent concentration methanol fuel that provided nearly 10 hours of power, he said.
Over the next few years, many of Japan's mobile phone makers will add power-hungry digital broadcast tuners to their mobile phone models. KDDI sees the fuel cell supplemental batteries as a useful way to reassure users that they will be able to watch TV on their mobile phones without worrying about the battery dying.
"When you are watching TV, and the battery is running out, you can plug these fuel cells in," Iriuchijima said. "That's what they are for."