Method for inspecting membrane electrode structure

Patent metadata

Field	Value
Publication number	US-11421985-B2
Application number	US-202117163950-A
Country	US
Kind code	B2
Filing date	Feb 1, 2021
Priority date	Feb 4, 2020
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

A method for inspecting a membrane electrode structure (1) which includes a first step in which detection medium capable of detecting elements of a first electrode catalyst layer (12) and a second electrode catalyst layer (22) and an element of a metal foreign matter (40) is sent along a thickness direction from the side of a first electrode layer (10) to a second electrode layer (20) side to obtain a thickness direction profile of a detection signal, and a second step in which an analysis unit identifies a thickness direction position of the metal foreign matter (40), from intensity of the detection signal in the thickness direction profile, and in which the analysis unit identifies thickness direction positions of the first and second electrode catalyst layer (12)(22), or a thickness direction position of an electrolyte membrane (30), from the intensity of the detection signal in the thickness direction profile.

First claim

What is claimed is:

1. A method for inspecting a membrane electrode structure formed by sandwiching an electrolyte membrane between a first electrode layer comprising a first electrode catalyst layer and a first gas diffusion layer, and a second electrode layer comprising a second electrode catalyst layer and a second gas diffusion layer, the method comprising:
a first step in which a detection medium capable of detecting elements of the first electrode catalyst layer and the second electrode catalyst layer or an element of the electrolyte membrane, and an element of a metal foreign matter is sent such that a focal point is moved along a thickness direction from a side of the first electrode layer to a side of the second electrode layer, thereby obtaining a thickness direction profile of a detection signal; and
a second step in which an analysis unit identifies a thickness direction position of the metal foreign matter, from intensity of the detection signal in the thickness direction profile, and in which the analysis unit identifies thickness direction positions of the first electrode catalyst layer and the second electrode catalyst layer, or a thickness direction position of the electrolyte membrane, from the intensity of the detection signal in the thickness direction profile.

2. The method for inspecting the membrane electrode structure according to claim 1 , comprising a third step in which the thickness direction position of the metal foreign matter identified by the second step is compared with the thickness direction positions of the first electrode catalyst layer and the second electrode catalyst layer, or the thickness direction position of the electrolyte membrane, and in which, when the metal foreign matter is spaced apart from the first electrode catalyst layer and the second electrode catalyst layer, or the electrolyte membrane, at equal to or more than a predetermined value in the thickness direction, the membrane electrode structure is determined as a non-defective product.

3. The method for inspecting the membrane electrode structure according to claim 2 ,
wherein the predetermined value is set to a value at which, when the metal foreign matter is present in the first gas diffusion layer or the second gas diffusion layer, the membrane electrode structure is not determined as the defective product.

4. The method for inspecting the membrane electrode structure according to claim 1 , comprising, prior to the first step, a scanning step of scanning a surface of the membrane electrode structure and detecting a presence or absence of the metal foreign matter,
wherein the first step and the second step are performed at a location where the metal foreign matter has been detected by the scanning step.

5. The method for inspecting the membrane electrode structure according to claim 1 , comprising a fourth step in which the thickness direction position of the metal foreign matter identified by the second step is compared with the thickness direction positions of the first electrode catalyst layer and the second electrode catalyst layer, or the thickness direction position of the electrolyte membrane, and in which, of manufacturing steps of the first electrode catalyst layer and the second electrode catalyst layer, the electrolyte membrane, and the membrane electrode structure, in which manufacturing step the metal foreign matter was mixed is identified.

Assignees

• Honda Motor Co Ltd

Inventors

• Shimada Koya
• Kurata Hiroshi
• Yoshida Shohei
• Shiraishi Keiichi

Classifications

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M4/8807

  Gas diffusion layers · CPC title

• G01N23/223

  by irradiating the sample with X-rays or gamma-rays and by measuring X-ray fluorescence · CPC title

• G01N23/04 Primary

  and forming images of the material · CPC title

• G01N2223/633

  thickness, density, surface weight (unit area) · CPC title