Gas diffusion electrode base material and method for producing same, and fuel cell

Patent metadata

Field	Value
Publication number	US-2025343248-A1
Application number	US-202218720788-A
Country	US
Kind code	A1
Filing date	Dec 26, 2022
Priority date	Dec 27, 2021
Publication date	Nov 6, 2025
Grant date	—

Abstract

A gas diffusion electrode medium for a fuel cell, which has high water repellent performance and excellent anti-flooding performance, can exhibit high power generation performance, and has high productivity is provided. A long gas diffusion electrode medium is composed of a conductive porous medium having a microporous layer containing a carbonaceous powder and a water repellent substance on one surface of the conductive porous medium, in which 65% or more of linear cracks observed in the microporous layer from the top surface are inclined at 45° to 90° from a width direction of the gas diffusion electrode medium.

First claim

1 . A long gas diffusion electrode medium comprising
a conductive porous medium having a microporous layer containing a carbonaceous powder and a water repellent substance on one surface of the conductive porous medium, wherein 65% or more of linear cracks observed in the microporous layer from the top surface are inclined at 45° to 90° from a width direction of the gas diffusion electrode medium.

2 . The gas diffusion electrode medium according to claim 1 , wherein 90% or more of cracks observed in the microporous layer from the top surface are linear cracks.

3 . The gas diffusion electrode medium according to claim 1 or 2 , wherein a number density of the linear cracks on the microporous layer is 0.20 to 50.00 cracks/cm 2 .

4 . The gas diffusion electrode medium according to claim 1 or 2 , wherein an average length of the linear cracks is 100 to 500 μm.

5 . The gas diffusion electrode medium according to claim 1 or 2 , wherein an average width of the linear cracks is 20 to 90 μm.

6 . The gas diffusion electrode medium according to claim 1 or 2 , wherein an occupied area of the linear cracks on the microporous layer is 0.01 to 0.70%.

7 . A fuel cell comprising:
the gas diffusion electrode medium according to claim 1 or 2 ; a polymer electrolyte membrane; a catalyst layer; and a bipolar plate as constituent members, wherein the bipolar plate functioning as a constituent member of the fuel cell has a groove channel, and 65% or more of linear cracks observed in the microporous layer from the top surface are inclined at 45° to 90° from a direction in which the groove channel extends.

8 . The method for producing a gas diffusion electrode medium having two steps of steps A and B to be described below:
Step A: a step of continuously coating one surface of a long conductive porous medium with a microporous layer coating liquid containing a carbonaceous powder and a water repellent substance, and then drying the long conductive porous medium at a temperature lower than 250° C. while the long conductive porous medium is deflected by 1 to 7 cm on a cross section in a width direction; and Step B: a step of sintering the conductive porous medium after step A at a temperature of 250° C. or higher.

9 . The method for producing a gas diffusion electrode medium according to claim 8 , the method having step C, which will be described below, before or after step A:
Step C: a step of applying a water repellent substance to the long conductive porous medium and drying the long conductive porous medium at a temperature lower than 250° C.

10 . A transportation apparatus using the fuel cell according to claim 7 as a power supply source.

Assignees

• Toray Industries

Inventors

• Utsunomiya Masamichi
• Watanabe Fumitaka

Classifications

• H01M2250/20

  Fuel cells in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M8/026

  characterised by grooves, e.g. their pitch or depth · CPC title

• H01M8/0243

  in the form of mixtures · CPC title

• H01M8/0234

  Carbonaceous material · CPC title

• H01M4/96

  Carbon-based electrodes · CPC title