JPS58126675A - Ion exchange membrane fuel cell and its manufacture - Google Patents

Abstract

PURPOSE:To provide a fuel cell electrode which is easy to make thin and has strong mechanical shock resistance by hot-pressing a metallic net electrode which is an electrode active mass and a current collector to an ion exchange membrane with a hot press to form one body. CONSTITUTION:''Nafion'' (registered trademark of DuPont) is used as an ion exchange membrane 2, and two platinum nets 1 which functions as an electrode active mass and a current collector are brought closely into contact with the both sides of the membrane. They are pressed at a pressure of 40kg/cm<2> for 5min at 200 deg.C with a hot press. By this process, the platinum net is half embedded into the ''Nafion'' which is softened by heat. Since the platinum net bites the ''Nafion'', the electrode resists mechanical vibration. As a metallic net for the electrode, nickel or palladium for a hydrogen electrode (a negative electrode) and silver or Raney nickel for an oxygen electrode (a positive electrode) are used besides platinum.

Description

[Detailed Description of the Invention] The present invention provides the structure of the ion exchange membrane fuel 'II Camellia for I pond and its manufacture! Regarding 22.

FIG. 1 shows the structure of a hydrogen/aX fuel II pond, which is a typical ion exchange 8Il fuel cell. Hydrogen flowing into the battery tank as fuel is decomposed and releases n1 electrons, generating traps and hydrogen ions. These hydrogen ions reach the positive electrode through ion exchange pst. At the positive electrode, hydrogen ions, electrons, and oxygen react to remove water. The movement of electrons from the negative electrode to the positive electrode in the above reaction results in a current that can be taken out from the fuel III cell.

The conventional one-piece structure was one in which the electrolyte ion exchange plate was sandwiched between conductive foil or mesh plates on both sides and secured with a plastic outer frame. The disadvantage of these II is that the battery is thinner than other types of batteries9.
It is at the point where a considerably high output can be obtained per unit volume or per unit weight.

However, since the outer frame is fixed, the contact between the mesh electrode and the ion exchange membrane is not necessarily uniform, and it is also susceptible to mechanical vibrations. Moreover, the advantage of thinning is diminished by the thickness of the outer frame.

In the present invention, a metal net-like 1iI positive material, which is the active material of the II electrode and a current collector, is integrated by hot pressing and bonding it onto an ion-exchange knitted fabric by thermocompression. In addition, compared to conventional products, it has become more resistant to mechanical shock, resulting in a dramatic increase in reliability. And what about batteries?
]IiI has become easier. In addition, the number of parts is reduced, and ease of assembly is greatly improved.

A hydrogen/oxygen fuel cell according to an embodiment of the present invention will be described below.

Nafion (registered trademark of DuPont) was used as the ion exchange membrane, and platinum wire mesh (which also served as a collector for the active material) was used as the ion exchange membrane.
1180) Place the two sheets in close layers on both sides. Then, during hot pressing, a pressure of aOK4/d is applied at 200° C. for 5 minutes.

By this operation, the diplatinum mesh is softened by the heat and is partially embedded into the Nafion. As a result, the net of platinum was cut into Nafion, and the mechanical vibration caused 4j.
I'm getting stronger. This ion interaction and the unification of longing
^A cross-sectional view of the object is shown in Figure 2.

This integrated ion-exchange membrane and electrode is shown in Figure 1, and when used in a container similar to the one shown below, it was found that the output of the fuel cell could be stably extracted even against external mechanical vibrations. became. Now that the electrode and ion exchange mt are integrated, the adhesion of the LD is semi-permanent and warped. tf
Not only has the number of parts A and C been reduced, but during assembly, it is no longer necessary to check and adjust the positions of the ion exchange membrane, W pole, and outer frame to improve layer density.

In addition to platinum, the metal mesh used for W* can also be used for hydrogen electrodes (
Nickel, palladium, and oxygen as negative electrodes! ! ! Silver or Raney nickel can be used as the positive electrode.

[Brief explanation of the drawing]

Figure w41 is a cross-sectional view showing fishing ground capture for one pond of hydrogen/ion exchange membrane fuel. 1...Water volume inlet 2...Oxygen inlet 3...Cascellato 4...Battery plate 5...Ion exchange membrane 6...11 pole 7...Gas chamber 8...Gas Figure 2 shows an integrated structure of an IN cable and an ion exchange membrane according to the present invention.
1-This is a cross section □ seen from the same direction as in Figure 1. 1...Metallic L14-shaped electrode 2...Cation exchange membrane or above Applicant Suwa Seiko Co., Ltd. Agent Tsutomu Mogami OΦ Figure 2

Claims (2)

[Claims] (1) I-electrode for ion-exchange membrane fuel cells in which the metallic net-like 11 I-electrode, which is the active material for the I-electrode and the current collector, is integrated with the ion-exchange membrane. (2) A method for producing a camellia for ion exchange membrane fuel 11 cell, in which a metal mesh is bonded to the cation exchange 11 using a hot press to make the electrode II for an ion exchange membrane fuel cell.