October 10, 2007 Toshiba demonstrated their latest Direct Methanol Fuel Cell (DMFC) technology at CEATEC Japan 2007 with the unveiling of a prototype version of the methanol powered Gigabeat multimedia player. Building on Toshiba’s previous offerings the new player can run for up to 10 hours on 10 milliliters of methanol, longer than would be possible using a similarly sized conventional battery. The prototype integrates the fuel cell power plant into the back of the player - which runs on nearly 100% methanol - and discharges the vapor created through natural evaporation. Besides playing music and video, the player is equipped with a TV-tuner and features a capacity meter for tracking the amount of fuel you've got left.
DMFCs produce electricity by adding fuel in the form of methanol to the anode or fuel side, this fuel is then separated into protons and electrons, along with carbon dioxide. The electrons are guided out of the fuel cell, forming an electric current, which is used to power the mobile device. The protons and electrons react with the air at the cathode to form water, which is expelled from the system and the system repeats. This process provides the benefit of providing power continuously without the need for recharging. All that is required is topping the fuel cells up with methanol, which can be done by pouring in fuel, or by swapping a cartridge. The fuel cell can even be topped-up even without having to turn off the device it is powering.
Although Toshiba and other companies have been working on DMFCs for a number of years, problems with the cost of manufacture of fuel cell components and a prohibition on methanol transportation on planes have hampered commercialization of the technology. Toshiba believes they have now overcome these problems with a predicted reduction in manufacture costs once they are put on the manufacture stream, eventually making them cheaper than alkaline batteries, while a recent announcement that the US Department of Transportation (USDOT) has moved to approve the devices for use on board commercial airlines, provided that the amount of fuel carried is within the allowed limit of 100 ml of liquid per container.
Aside from demonstrating the ability to fit a DMFC inside a small device Toshiba believes it has also overcome the problem of spillage when refilling the fuel cell. The user connects a clear plastic methanol cartridge to a port in the base of the player and presses a button on the cartridge, which releases methanol into the device’s reservoir. Once the reservoir is filled, the user releases the button and carbon dioxide produced by the fuel cell then pushes any methanol left between the reservoir and cartridge back inside the cartridge.
With all the potential advantages that DMFC technology offers, it is not hard to see why companies are investing heavily in the technology. A future where rejuvenating the laptop, mobile phone or portable media player with a dash of methanol replaces having to race off to the nearest power outlet can’t come soon enough for a society increasingly hooked on power hungry mobile devices. Toshiba is working on a range of devices powered by DMFC and hopes to start introducing them within one to two years. For further info visit Toshiba.