With development in IT in recent years, lithium ion secondary cells are used as power sources for almost all mobile instruments such as portable telephones, notebook-size personal computers, and digital camera. However, with an improvement in the performances of these mobile instruments, the power consumptions thereof tend to become increasingly large. Attention has been paid to fuel cells, which are clean and high in efficiency, for power sources or for charging the instruments.
When a fuel cell is used, in particular, in a portable instrument such as a notebook-size personal computer or a portable telephone, it is desired that the fuel cell has a structure capable of maintaining the portability thereof, or the smallness of the size thereof. It is therefore necessary for forming a fuel cell that its individual sections, such as its power generating cell and its fuel gas generating section, are effectively arranged.
A fuel cell made portable or small in size is known in Patent Document 1 described below by the present Japanese Patent Applicant. This fuel cell is equipped with: a cell body case composed of wall surface portions which constitute the external form of the cell body and at least face toward different directions; a supporting substrate arranged along the wall surface portions; unit cells (power generating cells) for power generation that are mounted on the supporting substrate; and a fuel gas generating section for generating a fuel gas, such as hydrogen gas, to be supplied to the power generating cells.
In this fuel cell, the unit cells each have a fuel gas channel, and the fuel gas channels of the unit cells are connected to each other through pipes. The document also discloses that a fuel gas generating unit is arranged in an inner space of the cell body case.
However, in a structure wherein a plurality of unit cells are connected to each other through pipes, as seen in the above-mentioned fuel cell, spaces for the pipes are wasteful. Thus, a limit is given onto technique for making such a fuel cell smaller. Additionally, the fuel gas generating unit is made of an independent structure; it is therefore necessary to use a package therefor, or a pipe for supplying the gas, so as to result also in a problem that a space for receiving a fuel gas generating agent decreases.
In the meantime, Patent Document 2 described below discloses a fuel cell having a structure wherein at the time of forming a structure composed of unit cells stacked on each other, a fuel gas can be supplied to power collector (electrode) surfaces of the unit cells through porous plates. About this fuel cell, a fuel gas supplying source is arranged outside the cell. The source is connected through a pipe or the like to a fuel supplying section in the form of an oblate box having, on the front and rear sides thereof, porous plates, respectively.    Patent Document 1: Japanese Registered Utility Model No. 3114148    Patent Document 2: JP-A-2003-282131