A new breakthrough in portable power
Miniature fuel cells promise a huge power boost to portable electronics ranging from mobile phones to power-hungry web-enabled handheld devices. Unlike today's most efficient lithium-ion mobile-phone batteries with an average of only four hours of talk time, micro fuel cells with a proper fuel store could provide longer talk time in off-grid situations. Moreover, this technology could be designed to be recyclable or disposable with user-friendly portable fuelling systems. The 'In situ H2 supply technology for micro fuel cells powering mobile electronics appliances' (ISH2SUP) project proposed two different solutions for fuelling micro fuel cells. The primary fuel — either methanol (CH3OH) or sodium borohydride (NaBH4) — is stored in a rechargeable cartridge. Electrical power is generated in the fuel cell using gaseous hydrogen released on demand from the cartridge. NaBH4-based technology was already known before the ISH2SUP project, but needed further development to make it suitable for long-term use in miniature fuel cells. Electrolysis of methanol, on the other hand was a completely new method, which needed extensive research. During the ISH2SUP project, different catalysts were examined and finally, platinum and an enzyme was chosen. Commercially available small fuel cells that produce one tenth of a watt to 50 watts were used to prove the feasibility of the new fuelling technologies. The prototypes developed included a battery and control electronics for hydrogen release. They were tested on a smart mobile phone and a laptop computer. For both these devices, a hydrogen driven charger was built. In situ production of hydrogen is not limited to the small power range examined in the ISH2SUP project. Research to extend its applicability from 100 watts to 1 kilowatt is scheduled for the final phase of the project. Thanks to high-energy fuels used, fuel cells can produce more energy for their weight than batteries ever will, supporting greater portability. Furthermore, electrolysis with the help an enzyme opens up interesting possibilities to cheaply produce hydrogen from different kinds of bio-decomposable wastes — including alcohols or sugars. This new class of power packs that is expected to enter into the market in the ensuing years might render the ubiquitous battery obsolete.
Keywords
micro fuel cells, hydrogen, power, mobile phone, , methanol, sodium borohydride, fuel cartridge, electrolysis, catalyst, platinum, enzyme, laptop
