JPS6160546B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a matrix fuel cell, and more particularly to an electrolyte replenishment device.

In this type of battery, it is necessary to stabilize the electrolyte matrix in order to operate the battery for a long period of time. The matrix interposed between the gas-diffusive positive and negative electrodes is impregnated with highly concentrated phosphoric acid.
The high temperatures and flow of reactive gas during battery operation dry the matrix, impairing battery performance. For this reason, methods are used, such as providing an electrolyte reservoir in the battery and replenishing the matrix with the electrolyte, or replenishing the matrix from outside the battery.

Since a conventional reservoir layer is placed on the back side of the electrode and communicates with the matrix through an opening in this electrode, the presence of the reservoir layer impairs the diffusion of the feed gas into the reaction zone and prevents the feed gas from flowing along the back side of the reservoir layer. There is a drawback that the supplied gas dries the reservoir layer itself and, in turn, reduces the amount of electrolyte in the matrix.

The present invention provides, in a battery stack consisting of a stack of unit cells and gas separation plates, an electrolyte storage groove in contact with the side edge of the matrix, in the peripheral area of the gas separation plate, that is, in an area that does not come into direct contact with the supply gas; An electrolytic solution supply path is formed that communicates the adjacent liquid storage grooves in a meandering manner, and each matrix is impregnated with an electrolytic solution that flows back and forth in each of the liquid storage grooves in sequence. This is how it was done.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. A battery stack 1 includes a unit cell consisting of positive and negative gas electrodes 3, 2 and an electrolyte holding matrix 4, and a hydrogen supply groove 5 and an air supply groove 6 on both sides of the unit cell, respectively. It is constructed by stacking a large number of carbon gas separation plates 7 arranged in the vertical direction and tightening them between upper and lower end plates (not shown).

Each gas separation plate 7 has an electrolyte storage groove 8 in contact with the side edge of the matrix 4 in the periphery of one side thereof, and these adjacent liquid storage grooves 8 are connected to an electrolyte supply channel as shown in FIG. 9 in a meandering manner. FIG. 2 is a longitudinal cross-sectional view of a part of the battery stack 1 along the liquid storage groove 8. As shown in FIG.

When the matrix 4 becomes dry due to long-term operation of the battery, if an electrolytic solution such as phosphoric acid is injected from the injection port (not shown) at the bottom of the battery stack 1, the electrolyte will flow through each liquid supply path 9 and each liquid storage groove. The fluid flows from the bottom to the top through the meandering fluid replacement path constituted by 8, and exits from the upper overflow port (not shown). The electrolytic solution flowing in a meandering manner sequentially fills each liquid storage groove 8 and impregnates the matrix 4 corresponding to these liquid storage grooves 8.

As described above, according to the present invention, in the periphery of each gas separation plate that constitutes the battery stack together with the unit cells, there are electrolytic solution storage grooves that contact the side edges of the matrix and electrolytic solution that communicates with these storage grooves in a meandering manner. Since the liquid supply path is formed, the replenished electrolyte uniformly fills each liquid storage groove while flowing in a meandering pattern, and the amount of liquid impregnated into the corresponding matrix becomes uniform, and the liquid storage grooves react. Since it is located in an area isolated from the gas, it has the advantage of being able to extend the fluid replacement cycle without being affected by the flow of the reactant gas, unlike conventional methods.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view of a main part of a battery stack according to the present invention, and FIG. 2 is a cross-sectional view of a part of the same battery stack along a liquid storage groove. 1: Battery stack, 3, 2: Positive and negative gas electrodes, 4: Matrix, 5: Hydrogen supply groove, 6: Air supply groove,
7: Gas separation plate, 8: Liquid storage groove, 9: Liquid supply path.

Claims (1)

[Claims] 1 A unit cell in which an electrolyte matrix is interposed between positive and negative gas electrodes, and gas separation plates each having positive and negative reaction gas supply grooves arranged on both sides, are stacked vertically, and the gas separation A matrix type fuel characterized in that an electrolyte storage groove in contact with the side edge of the matrix and an electrolyte supply path that communicates the upper and lower adjacent liquid storage grooves in a meandering manner are formed in the peripheral part of the plate. battery.