Membrane electrode assembly

Abstract

The present invention provides a method for preparing a membrane electrode assembly in which a microporous layer is applied to a catalyst layer. Also provided is a membrane electrode assembly obtainable by applying a microporous layer onto a catalyst layer.

Description

technical field [0001] The present invention provides a method for preparing a membrane electrode assembly, and a membrane electrode assembly obtainable by the method. The membrane electrode assembly includes a microporous layer applied to a catalyst layer. Background technique [0002] A fuel cell is an electrochemical cell comprising two electrodes separated by an electrolyte. A fuel such as hydrogen, an alcohol such as methanol or ethanol, or formic acid is supplied to the anode, and an oxidant such as oxygen or air is supplied to the cathode. Electrochemical reactions occur at the electrodes, and the chemical energy of the fuel and oxidant is converted into electrical energy and heat. Electrocatalysts are used to facilitate the electrochemical oxidation of fuel at the anode and the electrochemical reduction of oxygen at the cathode. [0003] Fuel cells are generally classified according to the nature of the electrolyte used. The electrolyte is typically a solid polym...

AI Technical Summary

Problems solved by technology

However, this manufacturing method has some disadvantages

Catalysts applied to the microporous layer may end up in deep pores within the gas diffusion layer, resulting in performance loss caused by long proton-conducting paths between the catalyst and the ion-conducting membrane

Also, in this design, the lamination pressure available to bond the catalyst layer to the ion-conducting membrane is low, since high bonding pressure will cause mechanical damage to the gas diffusion substrate structure such as fiber breakage

See also US 9,461,311 B2 and US 8,945,790 B2, modification of the microporous layer properties [14-17] and the addition of perforations in the microporous layer and / or gas diffusion substrate [18-20] have been reported previously as a means of minimizing performance loss. possible solutions, but none of these approaches physically eliminates the gaps that exist at the interface between the microporous layer and the catalyst layer

[0010] There remains a need for fuel cells that benefit from the presence of microporous layers, but in which the disadvantages of microporous layers are minimized, especially during operation at high current densities

Images