16 May 2007
Fuel Cells To Power Mobile Phones By 2009
STMicroelectrics hopes to be supplying fuel cell batteries for mobile phones by 2009. They are developing this new technology to power both mobile phones and laptop computers, and are aiming to have production underway by 2009.
“We are developing micro fuel cells for mobile phones and then for the laptop market,”
Salvatore Coffa, from the R&D department of the industrial and multi-segment sector at ST told the meeting. “We hope to have this in production by 2009.”
Coffa said the research is moving towards flexible substrates using PCBs for fuel cells delivering thin-film micro-batteries. Using fuel cells instead of batteries would make mobile phones lighter and much more convenient to use as they could be simply topped up with fuel whenever necessary.
In addition, there would be significant environmental benefits as the fuel can be derived from sustainable organic sources, while the by-products are mainly water and a much lower level of carbon dioxide than is produced by burning fossil fuels," says Dr. Salvo Coffa, who leads the Corporate Technology R&D team that is researching the micro fuel cell technology.
Nokia claims fuel cells for mobiles still 'years away'
The operation of a fuel cell involves the chemical interaction between hydrogen and oxygen to produce water, heat and electrical energy. Typically, a fuel cell consists of a pair of electrodes (the 'anode' and the 'cathode') separated by a membrane that allows protons (hydrogen ions) to pass through the membrane but does not allow an electric current to pass. In addition, catalysts such as platinum are used to increase the rate of the reaction and therefore the amount of electrical energy produced.
The main problem with applying fuel cell concepts to mobile phones is that the power source (battery or fuel cell) must be able to deliver around 300mA of current at 3.6V and it must not occupy a volume of more than around 12 cubic centimeters. However, the output current of a fuel cell is directly related to the common surface area between the electrodes and the membrane and to obtain 300mA of current using conventional fuel cell technologies would require a surface area of around 60 square centimeters, much larger than is available in a mobile phone.
ST is also researching bringing all plastic systems into manufacturing. These all plastic and silicon systems would include sensors, powered generation devices, antennas and other devices.
ST says that producing circuits on plastic rolls will benefit industry with their decreased possible sizes, and the company hopes to begin production of these plastic circuits in three years.
Achieved channel lengths for plastic circuits are 200-400µm, said Coffa, with ST targeting 10-40µm. Their announcement coincides with recently released US research that suggested that fuel cells would be viable mobile power options in the next 3-5 years.
"ST is committed to researching new technologies that could help to minimize the impact of industrial and consumer products on the global environment. Although there is still further work to do before these developments can be integrated into a commercial technology, we are very excited about their potential," says Coffa.