JPS6324563A - Fuel cell - Google Patents

Abstract

PURPOSE:To make a fuel cell thin by forming a gas separator of a gas impermeable dense layer and porous members arranged on both sides of the dense layer, and having gas flow passages in the porous members, and directly holding an electrode consisting of a catalyst layer only by the gas separators. CONSTITUTION:A gas separator 16 is furnished with a gas impermeable dense layer 13 and porous members 14 and 15 which have gas flow passages 11 and 12 on the both sides of the dense layers. On both sides of an electrolyte matrix 1, are arranged electrodes consisting of catalyst layers 6 and 7 only without base materials, contacting directly to the gas separators 16, and a fuel cell is composed of laminating such a structure plurally. By making the fed gas diffuse into the porous members 14 and 15 to spread over the electrode, the base material as a gas diffusing layer is not necessary, and a thinform cell is realized. Therefore, plural cells can be laminated in a same height, and the space factor to the output can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a cell configuration of a stacked fuel cell.

[Conventional technology]

FIG. 4 is a cross-sectional view showing a typical conventional cell configuration disclosed in Japanese Patent Application Laid-open No. 58-68881. In the figure,
(1) is an electrolyte matrix, (2) and (3) are electrodes, (4) and (5) are electrode base materials, (6) and (7)
) is the catalyst layer of the electrode, (8) and (9) are the wet gas seal parts, 00 is the gas separation plate (also called a separator or interconnector), and 01) and (6) are the fuel and oxidant gas perpendicular to each other. It is a gas flow path.

Next, the operation will be explained. The gas separation plate αQ is an air-impermeable plate made of, for example, dense carbon, and has mutually orthogonal gas flow paths (11, (6) formed on both sides thereof.On the other hand, the electrode base material (4)
) + (5) is made of porous carbon fiber, for example, and the fuel gas and oxidant gas supplied to the gas flow path aDl are diffused in the electrode base materials (4) and (5). It reaches the entire surface of the catalyst layers (6) and (7) of the electrode, reacts and generates electricity through the electrolyte matrix (1). here,
Excess gas that is not used in the reaction and steam gas that is a reaction product are discharged to the outside through the gas flow path (b) and (2). In this exhaust gas, the electrolyte contained in the electrolytic W matrix (1) and the electrodes (2) and (3) exists in the form of vapor determined by the operating conditions of the fuel cell, and the electrolyte is also discharged to the outside.

The wet Ganus seal (s + + (9)) prevents fuel and oxidant Ganus from leaking out from the porous wL electrode substrate.

[Problem that the invention seeks to solve]

While the conventional fuel cell is constructed as described above, the thickness of each part is
rL6~cL8'' rich electrode base material (41, (5) is t 1
8~! o 1m+, fuel electrode is tIlo6~α1, air electrode is tα1~α45111, electrolyte matrix (1) is t
(Since there are L15 to α25 II, the thickness of the basic unit structure of the cell is t4J to H3fl+.There was a problem that the height would increase when multi-layered. Also, the space factor for the output was poor.

This invention was made to solve the above-mentioned problems, and aims to provide a fuel cell that can reduce the thickness of the basic unit structure of the cell and improve the space factor for output. do.

[Means for solving the problem] Fuel according to this invention! The pond has a gas impermeable dense layer and porous sections arranged to form gas flow paths perpendicular to both sides of this dense layer, and this gas separating plate is a catalyst layer that does not contain a base material. Formed with chisel. It is designed to directly hold the electrodes.

[Effect]

In the structure of the fuel cell in this invention, the gas separation plate is formed by a gas-impermeable dense layer and a porous portion forming a gas flow path perpendicular to both sides of this dense layer, and the supplied gas is distributed over the entire surface of the electrode. Since it spreads, the base material as a gas diffusion layer of the II electrode is unnecessary and the structure can be made thinner.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (1) is an electrolyte matrix, (6) and (7) are electrode catalyst layers, (b) and (b) are mutually orthogonal gas flow paths for fuel and oxidant gas, and α is a gas separation plate. (referred to as composite lip separator) with dense layer (to)
and the rib-like porous portions α and (g) formed on both sides thereof are integrally constructed.

The thickness of each part is t for the dense layer 0 of the gas separation plate αQ.
α6～16111. The porous parts α◆, t1 to 1.5 each
Me, electrode catalyst layer (6) l (7) is the fuel electrode and t(LO
6~cL11111 air electrode t,, 1~1151E1,
Electrolyte matrix (1) is tα1~l125IEiK
Therefore, the thickness of the basic unit structure of the cell is t or 4 times.

Next, the operation will be explained. Fuel and oxidizing gas are supplied to the gas flows ll8 (b) and (2), which are perpendicular to each other formed by 4 and αG, to the porous portions on both sides of the gas separation plate (composite ribbed separator) (2), respectively. . At this time, the dense layer side of the gas separation plate α prevents the fuel and oxidizer flowing on both sides from mixing with each other, and both gases are directly or ) is diffused to reach the entire surface of the electrode catalyst layers (6) and (7).

The gas that has reached the catalyst layer is ionized and reacts through the electrolyte matrix (1) to generate electricity.

In a battery that has many unit cells stacked together, power is extracted from the top and bottom of the stack.

In the above embodiments, the porous portions α (and ao) were described as lip-shaped, but this is not necessary as long as gas can be uniformly supplied to the electrode catalyst layer, and as shown in FIG. 2, the gas flow paths αη, The porous portions may be arranged in a uniform stepping stone shape so that Q4 and (A) are formed.Also, the porous portions Q4 and (Q) are provided on both sides of the gas separation plate, but as shown in FIG. Either one may be formed of a conventional dense layer as shown in FIG.

〔Effect of the invention〕

As described above, 1.According to the present invention, the gas separation plate is made of a dense layer that does not allow gas to pass through, and the porous portions are provided on both sides of the dense layer to form gas flow paths, so that the gas diffuses through the porous portions. Since the base material layer as a diffusion layer of the electrode is not required, the cell thickness is small and a large number of cells can be stacked at the same height, which has the effect of improving the space factor for output.

Even more gas! Since the supply to the electrode is performed directly without going through the base material layer, the diffusion lower has the effect of improving shrinkage reduction characteristics.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a fuel cell according to one embodiment of the present invention, FIGS. 2 and 8 are sectional views showing other embodiments of the invention, and FIG. 4 is a conventional fuel cell. FIG. In the figure, (1) is an electrolyte matrix, (2) and (3) are electrodes, (6) and (7) are electrode catalyst layers, and 0
] and (2) are gas flow paths, Q3 is a dense layer, Q4 and (g) are porous parts, and Q6 is a gas separation plate. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A fuel cell in which a plurality of pairs of electrodes sandwiching an electrolyte matrix are stacked with gas separation plates interposed therebetween, characterized in that the gas separation plates directly sandwich an electrode catalyst layer.