Fuel Cell Gas Diffusion Layer Thickness Gradient
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fuel cells with gas diffusion layers featuring microporous layers comprising conductive microparticles experience uneven surface pressure and reduced gas diffusibility, leading to increased contact resistance and decreased power generation efficiency.
Innovation Solution
A gas diffusion layer with a conductive porous substrate and a microporous layer, where the microporous layer comprises carbon particles and a water-repellent resin, with a non-impregnating portion thickness between 0.0 μm and 20.0 μm and an impregnating portion thickness of 29% or lower, enhancing conductivity and gas diffusibility while maintaining low contact resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a microporous layer comprising conductive microparticles is situated on the surface of a water-repellent treated conductive porous substrate layer, then flooding is inhibited, but contact resistance increases and power generation efficiency decreases
Solution Approach 1:
The microporous layer is designed with spatially varying thickness: a first thickness in the region facing the gas flow path (to prevent flooding) and a second thickness in the region facing the catalyst layer (to maintain low contact resistance). This local differentiation allows each region to optimize its function independently.
Solution Approach 2:
The invention transitions from a uniform microporous layer to a gradient thickness structure, adding a dimensional variation (thickness gradient) to the originally homogeneous layer. This dimensional change enables simultaneous optimization of flooding prevention and electrical contact properties.
2Object-affected harmful factors
If a microporous layer is added to the gas diffusion layer, then flooding resistance improves, but gas diffusibility decreases
Solution Approach 1:
The microporous layer thickness is locally optimized: thicker in the gas flow path facing region to prevent flooding, and thinner in the catalyst layer facing region to maintain gas diffusibility. This spatial differentiation allows the layer to simultaneously provide flooding protection and adequate gas transport.
Solution Approach 2:
By introducing thickness variation across the microporous layer (creating a gradient structure), the invention resolves the contradiction between flooding resistance and gas diffusibility. The dimensional change in thickness allows different regions to fulfill different functional requirements.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution reduces contact resistance with the electrode catalyst layer and improves gas diffusion performance, maintaining structural integrity and simplifying the fuel cell construction while increasing power generation efficiency.
Implementation Method 1
a water-repellent resin
Implementation Method 2
gas diffusibility of the gas diffusion layer is lowered
Data Source
AI summary
The invention provides a gas diffusion layer for a fuel cell on which a microporous layer is disposed, which can have lower contact resistance with electrode catalyst layers and improved gas diffusion performance. The gas diffusion layer for a fuel cell of the disclosure has a conductive porous substrate layer and a microporous layer laminated in that order, wherein the microporous layer comprises carbon particles and a water-repellent resin, and has an impregnating portion that impregnates the conductive porous substrate layer and a non-impregnating portion that does not impregnate the conductive porous substrate layer, the thickness of the non-impregnating portion is greater than 0.0 μm and 20.0 μm or smaller, and the thickness of the impregnating portion is 29% or lower with respect to the total thickness of the microporous layer.