JPS59149657A - Fuel cell - Google Patents

Abstract

PURPOSE:To improve the mechanical strength of a one-sided grooved separator that comprises a fuel cell and facilitate the lamination of the cell by imbedding a reinforcement member made of metal inside. CONSTITUTION:A separator 6 is fabricated by mixing the carbon powder as the principal material and resin such as phenol resin as the bonding agent and molding and solidifying them under high temperatures and high pressure. In this case, a mesh 11 made of metal with the same relative coefficient of thermal expansion as carbon is inserted along the reverse surface on which grooves 6' are cut and is molded. Copper, aluminum, etc. are used as the mold. Since a reinforcement made of metal is imbedded inside, bending strength is improved and the separator will not be damaged by the unevenness of clamping pressure at lamination and oscillation.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to improving the mechanical strength of a single-sided grooved separator constituting a fuel cell, and relates to a fuel cell that facilitates cell stacking. .

[Technical background of the invention and its problems] Two methods have been considered for configuring fuel cells: a bipolar method and a lip-attached electrode method, but a hybrid method that takes advantage of both of these methods has also been proposed. ing. The configuration of the hybrid system is explained using Figure 1.
As the fuel electrode, an electrode 1 with a lip formed by cutting a groove for supplying fuel into a porous carbon material is used, and as an air electrode, a thin paper electrode 2 made of porous carbon material is used. A platinum-based catalyst is coated on one side of both electrodes to form a catalyst layer 3, and a matrix 4 holding an electrolyte such as phosphoric acid is sandwiched between them.

Fuel and oxidizer are supplied through the grooves 5 of the lipped electrode and the grooves 6' of the single-sided grooved separator 6, and an electromotive reaction is carried out by the battery.

In the bipolar system, the amount of phosphate electrolyte retained is small, and in order to obtain a long service life, it was necessary to provide a phosphate reservoir function with a complicated mechanism.

In addition, in the electrode method with a lip, the porous electrode retains phosphoric acid, making it possible to extend the lifespan, but as the air electrode becomes thicker, there is a problem in that gas diffusion is poor and battery performance deteriorates.

According to this hybrid method, it is possible to construct a battery that also has the function of retaining the phosphoric acid electrolyte and also has good gas diffusion on the air electrode side, resulting in improved cell characteristics and longer life.

On the other hand, since the voltage generated by a single cell in a combustible battery is as low as IV or less, a method is used to obtain output by stacking a large number of batteries as shown in FIG. Recently, there has been a call for increasing the capacity of these laminated batteries, and for this reason, batteries are becoming larger.
Furthermore, since it is considered to stack as many layers as possible within the transportation height limit, it is necessary to make battery component parts thinner.

For the above reasons, the allowable thickness of the single-sided grooved separator, which is a component part of a battery using the hybrid method, is a few inches or less, and since grooves must be cut into it, the remaining thickness is L.
It will be below H.

Moreover, the material of this single-sided grooved separator is suitable for high temperatures of batteries.
Because it is made from a graphite resin composition that is compression molded in a phosphoric acid atmosphere, it is brittle and prone to cracks. The role of the single-sided grooved separator in the hybrid system It has the important role of supplying oxygen to the battery and separating hydrogen and oxygen. Unbalance,
If cracks occur due to vibration during transportation, thermal cycles during operation, etc., there is a risk of explosion.

[Purpose of the invention]

The present invention has been made in consideration of these points, and an object of the present invention is to improve the mechanical strength of a separator with grooves on one side.

Embodiments of the Invention] The present invention will be described below with reference to the drawings. FIG. 3 is a partially cut away perspective view showing one embodiment of the present invention.

The method of manufacturing the separator 6 according to the present invention is to mix carbon powder as the main material and a resin such as phenol resin as a binder, and then mold and solidify the mixture under high temperature and high pressure. A metal mesh 11 having a coefficient of thermal expansion relatively similar to that of carbon is inserted and molded along the surface opposite to the surface where the droplet removal 6' is cut. As the metal, it is preferable to use copper aluminum or the like.

Moreover, as shown in FIG. 4, instead of the metal mesh 11, the groove 6
A similar effect can be obtained by inserting and molding tanzaku-shaped metal pieces 12 at equal intervals in a direction perpendicular to the cutting direction.

[Effects of the Invention] Even though the remaining thickness of the separate lake manufactured in this way is below the shoulder body, the metal reinforcement is embedded inside, so the bending strength is improved and the tightening during lamination is made with less pressure. It can fulfill its functions without being damaged even by uneven surfaces and vibrations.

[Brief explanation of the drawing]

FIG. 1 is a perspective view for explaining the stacked state of a battery constructed by a hybrid method, FIG. 2 is a diagram showing an example of the structure of a stacked battery, and FIG. 3 is a diagram showing an example of the present invention. FIG. 4 is a partially cutaway perspective view showing another embodiment of the present invention. ■... Ribbed electrode 2... Thin electrode 3... Catalyst layer 4... Matrix 5... Gas supply groove
6...Single-sided grooved separator 7...Power output terminal 8...Space 1-9...End plate to...
・Cold electrode plate 11...Metal mesh 12...Metal hack agent Patent attorney Nori Chika Kensuke (and 1 other person) No.
1 Figure 2 Flash 3 Figure 4

Claims (1)

[Claims] A fuel cell characterized in that the separator constituting the fuel cell has a groove on one side and a metal reinforcing member embedded inside the separator.