Batch production method of membrane electrode and manufacturing mould therefor

Abstract

The invention provides a batch production method of a membrane electrode, which can carry out batch production. The batch production method is characterized by comprising the following steps: (1) preparing an anode gas diffusion layer and a cathode gas diffusion layer which are of the same area; (2) coating a catalytic layer to form an anode gas diffusion electrode and a cathode gas diffusion electrode; (3) clipping the anode gas diffusion electrode and the cathode gas diffusion electrode into small pieces of gas diffusion electrodes of the same dimension and quantity; (4) respectively placing the small pieces of anode gas diffusion electrodes and the small pieces of cathode gas diffusion electrodes in upper ledge openings and lower ledge openings of a hot-pressing mould frame and tiling a proton exchange membrane between the upper edges and the lower edges; (5) placing the whole hot-pressing mould into a hot press to prepare a conjoined membrane electrode structure; and (6) separating the conjoined membrane electrode structure from the middle position of the proton exchange membrane of an adjacent single membrane electrode.

Description

technical field [0001] The invention relates to the technical field of membrane electrode production, in particular to a batch production method of membrane electrodes. Background technique [0002] The membrane electrode structure consists of five parts: the middle solid proton exchange membrane, the anode catalyst layer and the cathode catalyst layer on both sides of the proton exchange membrane, and the outermost anode gas diffusion layer and cathode gas diffusion layer, that is, the catalyst layer is always placed on the proton Between the exchange membrane and the gas diffusion layer on the same side. [0003] Based on the above structure of the membrane electrode, there are generally two methods for its preparation: [0004] The first is the process of coating the catalyst on the membrane and then hot pressing: that is, first coat the anode catalytic layer and the cathode catalytic layer on both sides of a proton exchange membrane, and then prepare an anode gas di...

AI Technical Summary

Problems solved by technology

[0009] First of all, the catalyst slurry is coated through a template with a geometric pattern. In order to ensure that the catalyst is not wasted, the catalyst must be coated in one geometric shape, and then coated with the catalyst in another area. The essence is to prepare a film piece by piece. Electrodes, so there are many repeated steps, wasting man-hours; if in order to save time, the catalyst is coated on all geometric shapes at the same time, that is, the coated area also includes the intermittent part of the template separating the various geometric shapes, it is self-evident , which is bound to waste a lot of catalyst;

[0010] Secondly, the biggest disadvantage of coating the catalyst on the proton exchange membrane is that the proton exchange membrane will more or less randomly shrink and deform during the coating process. Two cases can occur when overlaying the other side, namely, case 1: film shrinkage causes the area of ​​each geometry of the template to be larger than the area of ​​the coated catalyst layer, and case 2: the area of ​​the geometry in the template is larger than the area of ​​the coated catalyst layer. The above two cases will cause the entire electrochemical active area to be reduced, thereby wasting materials, and the actual output power of the battery cannot reach the design value;

[0011] Thirdly, for the catalyst-coated membrane with the catalytic layers on both sides completely corresponding and not dislocated, since the anode gas diffusion layer and the cathode gas diffusion layer have the same area as the catalytic layer, and the membrane is opaque after coating the catalyst, this will also cause the membrane When the electrode is hot-pressed, it is difficult to align the lower gas diffusion layer and the lower catalytic layer. Therefore, after the membrane electrode is hot-pressed, it is easy to cause misalignment between the upper and lower gas diffusion layers;

[0012] Finally, when up to 100 membrane electrodes are hot-pressed on one membrane at the same time, since there is no positioning device for the gas diffusion layers on the upper and lower sides, it will cause difficulty in assembly, and even cause the gas diffusion layers on the upper and lower sides of multiple membrane electrodes to be out of alignment. Serious consequences of misalignment

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