Hitachi, Toshiba Show Portable Fuel Cells
CHIBA, JAPAN -- Hitachi and Toshiba this week unveiled new fuel cell prototypes for a range of applications that could be commercialized as early as next year.
The prototypes on display at Ceatec Japan 2004 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 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 will make a lithium ion battery replacement fuel cell that it will put on sale in 2007, Mitsugu Nakabaru, senior engineer of Hitachi's fuel cell promotion and development group, says. 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 10 inches wide, 8 inches long, and between .4 inches and .8 inches thick. This includes a cartridge containing methanol that is diluted to a 20 percent to 30 percent concentration to produce power in the fuel cell. Hitachi is not disclosing the exact specifications, but the demonstration model weighs less than 2.2 pounds, says Nakabaru.
The prototype is designed to provide at least five hours of continuous operation for even the most power-hungry laptops while they are running multiple applications, Nakabaru says.
"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 says.
The laptop version is nearly ready for commercialization, but Hitachi is working to improve specifications, including developing the fuel cell's capability to use higher concentrations of methanol up to 40 percent, Nakabaru says. The company declined to discuss potential prices.
"It's nearly ready," he says.
Hitachi's fuel cell for PDAs, which the company already announced, is on target for sale in the second half of 2005, Nakabaru said. That prototype fuel cell is a cartridge type around .4 inches in diameter and between 2.0 inches and 2.4 inches in length. Specifications for the commercial model "are about the same," he says.
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 methanol at a concentration of 30 percent 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 stand-alone boxes with cords that plug into KDDI mobile phones. Both designs will be available before the end of March 2006, Youichi Iriuchijima, assistant manager of KDDI's IT development division, says.
Hitachi's fuel cell recharger is smaller than Toshiba's, but Toshiba's design will provide power for longer, Iriuchijima says.
The companies are not releasing details about size and weight, and the demonstration models were displayed under plastic.
The Hitachi version uses 46 percent methanol concentration fuel to provide 700 milliwatts and 3.5 volts, that is capable of providing at least 5 hours of supplemental power when a lithium ion battery is exhausted, Iriuchijima says. The Toshiba prototype uses a 100 percent concentration methanol fuel that provides nearer 10 hours of power, he says.
Power Hungry Devices
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. That's what they are for," Iriuchijima says.
The fuel cells will be able to connect into all KDDI phone models, not just those made by Hitachi and Toshiba, he says.
"The Toshiba and Hitachi versions are for KDDI. Fujitsu's is for NTT DoCoMo. But we are encouraging other companies to join us," Iriuchijima says.
Like Fujitsu, Hitachi is working towards commercializing a fuel cell that will replace the lithium ion battery completely, and this will be commercially available in 2007, says Hitachi's Nakabaru. While Hitachi is not giving details about the battery version, the initial design will be between two and three times more bulky than conventional batteries, he says.
"It's going to take some time, and it's going to be a bit big," he says.