JPH0425675B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel cell, and particularly to a structure of a unit cell that is advantageous for stacking operations.

[Background of the invention]

Conventionally, a unit cell constituting a fuel cell has two electrode plates 1, each having a gas flow path, as shown in FIG.
Catalyst layers 2, 2' are provided on the surface of 1' opposite to the gas flow path,
An electrolyte layer 3 is sandwiched between the catalyst layers.
In this case, the electrodes are attached so that the gas flow paths of the electrodes cross each other. Electrode plate 1, 1'
has pores through which gas particles can pass in order to guide fuel gas or air from the gas flow path to the catalyst layer 2. A plurality of unit batteries configured in this manner are stacked, and a manifold 5 for supplying and discharging gas from the outside to the battery is attached to the side surface of the unit battery.

In FIG. 2, the surface of this manifold 5 that contacts the stacked battery must be sealed with a gasket 6 or a sealant to prevent gas from leaking out of the battery from the surface that is mated to the battery. However, as mentioned above, since the electrode plate 1 is porous, gas leaks through the holes in the direction of the arrow in the figure. For this reason, the ends of the electrode plate 1 are made denser by forming pores or impregnating the pores with resin, or by being wrapped in a special film. However, even with such measures, it is still not sufficient. This is because misalignment of the unit cells that occurs during stacking creates unevenness on the contact surface between the manifold 5 and the stacked batteries, which tends to result in incomplete sealing.

As described above, in conventional batteries, even if the ends of the electrodes were sealed, complete sealing could not be expected, and safety problems remained.

[Purpose of the invention]

An object of the present invention is to provide a unit battery with good workability and high sealability by making the ends of the electrodes independent from the electrodes themselves.

[Summary of the invention]

That is, in the present invention, the unit battery is composed of the following.

That is, it is formed into a frame-like body from an insulating material, and the frame sides are formed in a cross-shaped shape so that both sides have a step with respect to the opposite side, and the inner wall of the central part in the thickness direction of the frame state is A frame body having a recessed part having a predetermined width, one electrode housed in the low level difference side on one side of the frame body, and another electrode housed in the low level difference side on the opposite side of the frame body. In order to achieve the desired purpose, the electrolyte is formed of an electrode and an electrolyte filled in the recess of the frame between the two electrodes.

[Embodiments of the invention]

The present invention will be explained below based on the illustrated embodiments.

In FIG. 3, a solvent layer 2 is applied to the electrode 1,
Frame 7 is made of fluororesin and integrally molded into a cross-shaped structure.
Attach so that the gas flow path is parallel to the frame. One electrode 1' is attached to the opposite side so as to be parallel to the frame 7 (so that the gas flow paths of both electrodes intersect).
That is, the frame 7 is formed as follows. A groove 7a extending in one direction is provided on one side of a square insulating thick plate, leaving both ends intact, and a similar groove is provided on the opposite side, but the grooves are provided so as to intersect with each other. , and the grooves pass through the plate in the thickness direction. It is formed in a so-called parallel grid shape.

Electrodes 1 and 1' are housed in these grooves, respectively. In this case, the electrode is placed in such a way that it fits into this groove, so the electrode has a rectangular shape.

Furthermore, as shown in FIG. 4, the frame 7 is provided with a recess 8 at the center in the thickness direction of the frame, in which the electrolyte layer 3 is placed.

Electrolyte layer 3 and electrode 1 are placed in this recess 8 and groove 7a.
1' is applied to each.

A unit battery with each part applied in this way,
By tightening it in the thickness direction, the electrode 1,
1' into this groove completely. The electrolyte between the electrodes 1 and 1' is crushed and expanded in the horizontal direction by the pressing force, and is filled into the recess 8 of the frame 7. In the battery formed in this way, the fuel gas tends to leak from the gas flow path to the outside via the pores at the end of the electrode depending on the gas pressure, but the direction is changed by the frame 7. One side is blocked by the separator 4 and the other side is blocked by the electrolyte layer 3, and leakage is stopped. The same can be said about the air side. After stacking multiple unit batteries, a manifold 5 for supplying and discharging gas is attached, but the area around this battery is
Since only the side wall surface of the frame 7 is formed to a certain size, misalignment during stacking is extremely small, and the seal between the manifold and the stacked battery is perfect. Furthermore, since the separator and the battery are not stacked separately during stacking, the work becomes easier. As described above, according to this embodiment, since gas does not leak through the electrode, there is no need for a special gas seal on the electrode. Since the stacking misalignment between unit batteries can be reduced, the seal between the manifold and the stacked batteries is perfect, and a highly safe battery can be provided. In addition, by appropriately adjusting the width of the recess filled with the electrolyte mentioned above, the electrolyte can be made to the desired thickness and can be kept constant, which was previously necessary to maintain the electrolyte thickness. Spacers are no longer necessary.

FIG. 5 shows another embodiment of the invention.

The difference from the previous one is that a rectangular guide hole is provided in the integrally molded frame. By inserting the guide pin 9 into this hole, it is possible to eliminate stacking misalignment when stacking batteries, and it can also be used as is as a tightening bolt for batteries. in this case,
Since the distance between the four tightening bolts is narrower than that of the conventional one, the fastener can be made smaller.

Figure 6 shows a frame made by combining rod-shaped bodies, with the frame's materials being formed into a straight line and the four corners fixed with rivets made of the same material as the frame.
In this case, there is no need for a molding machine for molding the frame or a molding device such as a press, so it has the advantage of being easy to implement.

FIG. 7 is a diagram showing another example of application, in which grooves 10 are provided on the surface of the integrally molded frame 7 that contacts the electrolyte, and the electrolyte layer in contact with the grooves constitutes a passage. The passage communicates with a small hole 11 provided in the side of the frame. This small hole 11 is further connected through a conduit 12 to an electrolyte supply tank outside the battery.
The electrolytic solution reaches the small hole 11 of the frame 7 constituting the unit battery from the supply tank, and reaches the electrolyte layer 3 via the grooved part 10 of the frame. In this example, since the frame 7 can be used as an electrolyte passage, the electrolyte can be easily replenished.

〔Effect of the invention〕

According to the present invention, since both ends of the electrode are covered with a frame, there is no need to seal the ends of the electrode itself, and since the separator is integrated with the unit electrode, assembly is easy, and the unit battery Since it is only necessary to align the peripheral edges between the two, it is easy to align the sides of the entire battery, reducing unevenness between the stacked battery and the manifold, improving sealing performance, and increasing safety during battery operation.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional battery, FIG. 2 is a cross-sectional view of a conventional battery, FIG. 3 is a partially cutaway perspective view of a unit potential of the present invention, and FIG. 4 is a schematic diagram of a unit battery of the present invention. 5 and 6 are perspective views showing another embodiment of the present invention, and FIG. 7 is an end sectional view of another embodiment. 1... Electrode, 2... Catalyst layer, 3... Electrolyte layer,
7...Frame.

Claims (1)

[Scope of Claims] 1. A battery body in which unit cells are stacked in multiple stages with separators interposed therebetween; and a manifold disposed on the side surface of the battery body for supplying and discharging fuel gas and air to the battery body. , in a fuel cell in which the unit cell is formed by sandwiching an electrolyte between two electrodes having a gas flow path, the unit cell is formed into a frame-like body made of an insulating material, and the sides of the frame are opposite to each other. A frame body that is formed in a parallel cross shape so that both sides have a step with respect to the sides, and that has a recessed part having a predetermined width on the inner wall of the central part in the thickness direction of the frame body; and one side surface of the frame body. one electrode housed on the low step side of the frame, another electrode housed on the low step side on the opposite side of the frame, and an electrode filled between the two electrodes and in the recess of the frame body. formed from an electrolyte and A fuel cell characterized by: 2. The fuel according to claim 1, characterized in that a guide hole is provided in the rectangular plane part of the frame, and the battery body is tightened by a guide pin that is inserted into the guide hole and also serves as a tightener. battery. 3. The fuel according to claim 1, wherein the frame is provided with a small hole that penetrates from the outside of the frame to the recess, and the small hole is communicated with an electrolyte replenishment tank outside the battery. battery.