# US 11,444,291 B2 · Gas diffusion layer

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,444,291 B2
- Document ID: US11444291B2
- Status: Granted
- Kind: B2
- Application number: 16/267,831
- Filed: 2019-02-05
- Published: 2019-09-05
- Granted: 2022-09-13
- Earliest claimed: 2018-03-01
- Assignees: Toyota Jidosha Kabushiki Kaisha
- Applicants: Toyota Jidosha Kabushiki Kaisha
- Inventors: Takeaki Saito
- Web page: https://patentgrep.com/patent/US11444291B2

## CPC

- H01M 8/0234: Carbonaceous material
- H01M 8/026: characterised by grooves, e.g. their pitch or depth
- H01M 8/0245: in the form of layered or coated products
- H01M 2008/1095: {Fuel cells with polymeric electrolytes}
- Y02E 60/50: Fuel cells
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

To provide a gas diffusion layer that allows reducing an increase in contact resistance with a separator and also allows reducing deterioration of gas diffusivity. The gas diffusion layer is disposed in contact with a separator including a grooved fluid flow passage. The gas diffusion layer includes a diffusion layer substrate and a water-repellent layer. The diffusion layer substrate has a ratio of a pore diameter to a thickness of 0.35 or more. The water-repellent layer is disposed on a surface of the diffusion layer substrate. The diffusion layer substrate is made of a carbon fiber. A content rate of the carbon fiber is 30% or more.

## Claims

### Claim 1

A gas diffusion layer disposed in contact with a separator including a grooved fluid flow passage,
wherein the gas diffusion layer comprises:
a diffusion layer substrate that has a ratio of a pore diameter to a thickness of 0.35 or more,
wherein, in the diffusion layer substrate,
a ratio of a normal air permeability to an in-plane air permeability is 45×106 or more,
the diffusion layer substrate includes a conductive carbon fiber, and
a content rate of the conductive carbon fiber is 30% or more.

### Claim 2 (depends on 1)

The gas diffusion layer disposed in contact with a separator including a grooved fluid flow passage according to claim 1,
wherein the conductive carbon fiber is a carbon paper or a carbon cloth.

### Claim 3 (depends on 1)

A fuel cell comprising the gas diffusion layer disposed in contact with a separator including a grooved fluid flow passage according to claim 1.