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The rapid growth of the portable electronics market includes ‘power-hungry’ accessories in a smaller system, which has led to the search for an alternative and advanced power source due to the limited energy density of conventional lithium-ion batteries. Table 1 lists the power demand of the different portable applications. Fuel cells promise to provide a more reliable and longer operational time than batteries. As the energy is stored as a reservoir rather than as an integral part of the power source, fuel cells have advantages over batteries. Micro fuel cell products compete with power systems that utilize both direct. | Portable Devices Fuel Cells A Kundu Queen s RMC Fuel Cell Research Centre Kingston ON Canada JH Jang Samsung Electro-Mechanics Gyunngi-Do Republic of Korea 2009 Elsevier B.V. All rights reserved. Introduction The rapid growth of the portable electronics market includes power-hungry accessories in a smaller system which has led to the search for an alternative and advanced power source due to the limited energy density of conventional lithium-ion batteries. Table 1 lists the power demand of the different portable applications. Fuel cells promise to provide a more reliable and longer operational time than batteries. As the energy is stored as a reservoir rather than as an integral part of the power source fuel cells have advantages over batteries. Micro fuel cell products compete with power systems that utilize both direct and indirect energy conversion methods. Direct conversion may involve fuels such as methanol ethanol formic acid ethylene glycol and sodium borohydride that are converted into electrons through a direct fuel cell system. Indirect methods require the conversion of methanol ethanol or sodium borohydride into hydrogen. The direct supply of pure hydrogen is relatively difficult in electronic equipment applications due to storage problems i.e. the lack of an efficient hydrogen storage material . There is also concern in terms of safety while carrying pure hydrogen in electrical equipment. The setup of a cost-effective appropriate infrastructure for distribution of hydrogen canisters is another major challenge for which most hurdles are unlikely to be overcome in the foreseeable future. In the direct alcohol fuel cell system the main studies center on methanol direct methanol fuel cell DMFC although ethanol-fueled systems have drawn interest in recent years. Direct mathanol fuel cell has the Table 1 The power demand of the different portable applications Items Power required W Cellular phone 1 Personal digital assistant PDA 1 Notebook personal computer .
