JPS62237671A - Electrolyte retaining structure of fuel cell - Google Patents

Abstract

PURPOSE:To maintain the steady performance of an electrolyte plate over a long period of time by installing an electrolyte reservoir in the circumference of a fuel cell, supplementing the electrolyte in the reservoir to an electrolyte plate during shortage, and storing the electrolyte in the reservoir during excess. CONSTITUTION:An electrolyte reservoir 8 having an L-shaped cross section is installed at the end of a seaprator 2 as electrolyte retaining structure. When the electrolyte in an electrolyte plate 5 is consumed and cell performance is decreased, by increasing the pressure P1 in a manifold 7 than the pressure P2 in the electrolyte plate 5, an electrolyte 9 in the reservoir 8 penetrates in an arrow direction from the end of the electrolyte plate 5 and the electrolyte 9 is supplemented to the electrolyte plate 5. When supply of reaction gas is stopped in starting or in discontinuing of power generation, molten electrolyte directly flows out from an end plate 1 because of no consumption of electrolyte. This electrolyte is stored in the reservoir 8, and flow out to the outside is prevented. Therefore, corrosion of the end of the separator 2 caused by electrolyte is prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrolyte holding structure for a fuel cell, and particularly to a fuel cell t-retaining structure that takes measures to replenish electrolyte and prevent electrolyte outflow.
Regarding solute retention structure.

[Conventional technology]

Since the fuel cell operates at high temperature and l/I'', the electrolyte is in a molten state. Therefore, inside the fuel cell.

Much of the It electrolyte is lost due to the reactive gas carrying away the It electrolyte to the outside, and the melted electrolyte flowing out from the outer periphery of the battery.

As a measure to prevent the loss of electrolyte, various proposals have been made in the past, particularly from the perspective of electrolyte replenishment structures. For example, there is a separator in which a groove for storing an electrolyte is formed in the wet seal portion of the separator, and the electrolyte is previously stored in this groove at r=i. In this model, only a fixed amount of 'gIt solute can be supplied, so if the supply power becomes zero during operation,
Measures are taken to disassemble and replenish the battery.

In addition, related equipment in this building includes, for example,
v! Ti No. 58-23166 is mentioned.

[Problem that the invention seeks to solve]

However, with the above conventional technology, if the replenishment amount becomes zero during operation, the battery must be disassembled and replenished, which not only makes maintenance difficult, but also causes excess electrolyte to overflow from the outer periphery depending on the operating conditions. There were other problems.

The purpose of the present invention is to replenish electrolytes according to the state of the electrolyte plate,
One object of the present invention is to provide an electrolyte holding structure for a fuel cell that is easy to maintain and prevents VL electrolyte outflow.

[Means for solving problems]

The above purpose is to provide an electrolyte reservoir on the outer peripheral surface of the fuel cell,
When replenishing, electrolyte is introduced into the reservoir.

This is achieved by allowing the electrolyte to overflow into the reservoir in case of excess.

[Effect]

In the electrolyte reservoir located on the outer periphery of the 1ets quality plate,
'The supply of electrolyte and the reception of excess electrolyte function as a receptacle. As a result, the supplied electrolyte permeates through the side surface of the electrolyte plate and impregnates the inside, and excess electrolyte does not leak out to the outside, making maintenance easier.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In FIG. 1, the fuel cell is constructed by having an electrode 3 disposed between an end plate 1 and a separator 2, and a reaction gas passage 4 provided on one side of the electrode 3.

A 'rii solute plate 5 is provided between the electrodes 3, and this solute plate 5 and the electrode 3 have a structure in which blocks are laminated. Furthermore, a grate structure 6 is provided at the end of the end plate l, forming a manifold 7.

In a fuel cell having such a structure, a zeolite storage section 8 serving as an electrolyte holding structure is provided so as to have a KL-shaped end portion of the separator 2.

, π2 is a plan view of the actual example shown in FIG. As shown in FIG. 2, the end of the -4 solute reservoir 8 is machined so that the manifold 7 comes into contact with the plate structure 6.

In the above configuration, the reaction gas is introduced into the manifold old 7 and then overcomes the electrolyte reservoir 8 and is supplied to the gas flow path 4.

When the electrolyte in the electrolyte plate 5 disappears and a decrease in battery performance is observed, the introduction of the reactant gas is temporarily stopped, and the plate structure 6 is removed from the end plate 1.

Electrolyte 9 is introduced into each electrolyte reservoir 8 as shown in FIG. Next, after attaching the plate structure 6 to the end plate 1, one reaction gas is introduced into the mania old 7. At this time, the pressure P+ in the mania old 7 is changed to t@quality plate 5
By setting the pressure higher than the medium pressure Pz, the electrolyte 9 introduced into the electrolyte reservoir 8 permeates from the end face of the electrolyte plate 5 in the direction of the broken line arrow, and the CFT platinum 9 is deposited on the heart release plate 5. will be replenished.

At this time, it is not preferable to make the pressure inside the mania old 7 higher than the allowable withstand pressure of the decomposition plate 5 (P+t'4).

In addition, if the introduction of the reaction gas is stopped during startup or generation interruption, 1! Since there is no consumption of platinum, the molten IE platinum directly flows out from the end plate l. This electrolyte is stored in the electrolyte reservoir 8.

External leakage is prevented. As a result, corrosion of the end face of the separator 2 due to the electrolyte is prevented.

FIG. 4 shows another example of the electrolyte reservoir, in which an electrolyte reservoir 8 is formed by fixing a reservoir member 10 having an L-shaped cross section to the end of the separator 2 by welding or the like. . The reservoir member IO can be made of a material with high corrosion resistance, such as ceramics. Although the configuration shown in FIG. 4 increases the number of parts, it simplifies the structure, improves workability, and furthermore prevents corrosion of the electrolyte reservoir 8.

In addition, the effluent electrolyte is free from corrosion products.

It is also possible to replenish.

[Effects of the Invention] As explained above, according to the present invention, maintenance for electrolyte replenishment and outflow prevention can be achieved with a simple configuration, making it possible to maintain stable performance of the IT board over a long period of time. Therefore, it is possible to extend the life of one battery.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing a fuel cell showing one embodiment of the present invention, and FIG. 2 is a plan view of the embodiment of FIG. 1. FIG. 3 is an explanatory diagram of the operation of the embodiment of the present invention, and FIG. 4 is a sectional view showing another embodiment of the electrolyte reservoir. ■... End plate, 2... Separator, 3... Electrode, 4
···aisle. 5... Electrolyte plate, 6... Plate structure, 7...
Manifold, 8... Electrolyte reservoir, 9... Electrolyte, 10... Reservoir member.
.

Claims (1)

[Scope of Claims] 1. A fuel cell configured to include a separator having a gas flow path, an electrode disposed in contact with the gas flow path, and an electrolyte plate disposed between the electrodes, An electrolyte holding structure for a fuel cell, characterized in that an electrolyte reservoir is provided adjacent to an end of the electrolyte plate. 2. The electrolyte holding structure for a fuel cell according to claim 1, wherein the electrolyte reservoir is formed integrally with the separator at an outer peripheral portion of the separator. 3. The electrolyte holding structure for a fuel cell according to claim 1, wherein a reservoir member having an L-shaped cross section is attached to the outer periphery of the separator to constitute the electrolyte reservoir. .