Micro-porous layer and manufacturing method therefor, gas diffusion electrode substrate, and fuel battery

Patent metadata

Field	Value
Publication number	US-2020313200-A1
Application number	US-201816763266-A
Country	US
Kind code	A1
Filing date	Nov 21, 2018
Priority date	Nov 29, 2017
Publication date	Oct 1, 2020
Grant date	—

Abstract

The present invention provides a micro-porous layer which provides a fuel battery having high productivity, high power generation performance, and high durability. The present invention provides a micro-porous layer including fibrous carbohydrate having a fiber diameter of 5 nm-10 μm and an aspect ratio of 10 or more. The carbohydrate has an oxygen/carbon element ratio of 0.02 or more.

First claim

1 . A micro-porous layer comprising a fibrous carbide having a fiber diameter of 5 nm or more and 10 μm or less and an aspect ratio of 10 or more,
wherein an oxygen/carbon element ratio of the carbide is 0.02 or more.

2 . The micro-porous layer according to claim 1 , wherein the carbide has a fiber diameter of 5 nm or more and 100 nm or less.

3 . The micro-porous layer according to claim 1 , wherein the carbide has a fiber diameter of 500 nm or more and 10 μm or less.

4 . The micro-porous layer according to claim 1 , wherein a fluorine/carbon element ratio of the carbide is smaller than an average fluorine/carbon element ratio of the micro-porous layer.

5 . The micro-porous layer according to claim 1 , wherein a cross section of the micro-porous layer contains the carbides in an amount of 1,000/mm 2 or more.

6 . The micro-porous layer according to claim 1 , comprising carbon black, a water-repellent substance, and the carbide.

7 . A micro-porous layer having a contact angle with a droplet obtained by mixing 2-propanol and water at a ratio of 1:2 of 80° or more, comprising a conductive material having an aspect ratio of less than 20, and comprising substantially no crack.

8 . The micro-porous layer according to claim 7 , having an average pore size of 200 nm or less.

9 . The micro-porous layer according to claim 7 , comprising a water-repellent substance having a melt viscosity of 10 9 Pa·s or less.

10 . A gas diffusion electrode substrate comprising the micro-porous layer according to claim 1 .

11 . A fuel battery comprising the micro-porous layer according to claim 1 .

12 . A method for manufacturing a micro-porous layer, comprising:
drying ink containing a conductive material having an aspect ratio of less than 20 and a crack suppressing material having an aspect ratio of 2 or more; and after the drying, performing a heat treatment at a temperature higher than a temperature in the drying step to decompose and remove the crack suppressing material.

Assignees

• Toray Industries

Inventors

• Utsunomiya Masamichi
• Kajiwara Kentaro
• Watanabe Fumitaka
• Tanimura Yasuaki

Classifications

• Y02E60/50

  Fuel cells · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/1004

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title

• H01M4/8882

  Heat treatment, e.g. drying, baking · CPC title

• H01M4/861 Primary

  with a gradient in the porosity · CPC title