1. Field
One embodiment of the present invention relates to an electronic apparatus system provided with an electronic apparatus and a fuel cell device for supplying current to the electronic apparatus.
2. Description of the Related Art
Presently, secondary batteries, such as lithium ion batteries, are mainly used as energy sources for portable notebook personal computers (notebook PCs), mobile devices, and other electronic devices. In recent years, small, high-output fuel cells that require no charging have been expected as new energy sources to meet the demands for increased energy consumption and prolonged use of these electronic devices with higher functions. There are various types of fuel cells. In a direct-methanol fuel cell (DMFC) that uses a methanol solution as its fuel, in particular, the fuel can be handled more easily than in a fuel cell that uses hydrogen, so that the system is simpler. Thus, the DMFC is a noticeable energy source for an electronic device.
Usually, a DMFC is provided with a fuel tank that contains methanol, a liquid pump for force-feeding the methanol into an electromotive section, an air pump for feeding air into the electromotive section, etc. The electromotive section is provided with a cell stack that is formed by stacking in layers a plurality of single cells each including an anode and a cathode. The methanol and air are supplied to the anode and the cathode, respectively, whereby electricity is generated based on a chemical reaction. As reaction products that are produced by the generation of electricity, unreacted methanol and carbon dioxide are produced on the anode side of the electromotive section, and water on the cathode side. The water as the reaction product is changed into steam and discharged.
According to a fuel cell electricity generating device described in Jpn. Pat. Appln. KOKAI Publication No. 2005-183014, for example, unreacted methanol and carbon dioxide produced on the anode side of an electromotive section are delivered to a gas-liquid separator, in which the methanol and carbon dioxide are separated. After the separation, a gas component is cleared of harmful substances by a purifying filter and then fed to a cathode channel through an exhaust passage.
Prevailing purifying filters for removing impurities in gas components utilize a catalytic reaction. The higher the temperature, the faster this catalytic reaction is accelerated, and the more the purification performance to remove impurities is improved.
In the fuel cell electricity generating device constructed in this manner, the purifying filter may possibly be heated to high temperature by a heat generating element, such as a heater, in order to accelerate the catalytic reaction of the filter. If the heater is an independent unit, however, it is not practical because of its high energy consumption and hinders the miniaturization of the fuel cell device.