Catalyst Coated Membrane Lamination via Support Film Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for preparing catalyst coated membranes face issues such as uncontrolled dimensional changes, formation of wrinkles and cracks, and require high technology and complex processes, especially when dealing with thin polymer electrolyte membranes.
Innovation Solution
A method involving the lamination of two partial catalyst layers, where one layer is in a non-dried state to ensure adhesion, with a support film stabilizing the membrane during coating and drying steps to prevent dimensional changes, and subsequent removal of the substrate to form a catalyst coated membrane with high homogeneity and quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a catalyst dispersion is coated directly onto a free-standing membrane, then the catalyst layer can be formed directly on the membrane, but uncontrolled dimensional changes occur in the membrane leading to wrinkles and cracks
Solution Approach 1:
A support film is introduced as an intermediary element between the membrane and the coating process. The support film provides mechanical stability during catalyst dispersion coating and drying, preventing dimensional changes, wrinkles, and cracks in the thin membrane. After coating, the support film is removed, leaving the membrane with a stable catalyst layer.
Solution Approach 2:
The support film is applied to the membrane before the catalyst dispersion coating process. This preliminary action stabilizes the membrane structure in advance, preventing dimensional changes during subsequent coating and drying operations. The support film is removed after the catalyst layer is formed.
2Ease of operation
If both catalyst layers are dried before lamination, then the catalyst layers are stable and easy to handle, but adhesion between the layers is insufficient
Solution Approach 1:
The drying state of catalyst layers is changed as a controllable parameter. One catalyst layer is kept in a non-dried (wet) state during lamination to ensure adequate adhesion, while the other layer can be dried for stability. This parameter adjustment allows both good adhesion and handling stability to be achieved.
3Productivity
If thin polymer electrolyte membranes (10-20 μm) are used, then the membrane electrode assembly performance is improved, but uncontrolled dimensional changes and formation of wrinkles and cracks occur during processing
Solution Approach 1:
The support film acts as a mediator that enables processing of thin membranes (10-20 μm) without dimensional instability. During catalyst coating and drying, the support film prevents wrinkles and cracks that would otherwise occur in such thin membranes. After processing, the support film is removed, leaving the thin membrane with a stable catalyst layer.
4Manufacturing precision
If catalyst layers are formed on inert temporary substrates and then transferred, then good catalyst layer formation is achieved, but additional substrates increase process costs and complexity
Solution Approach 1:
The support film serves as a temporary intermediary substrate during catalyst coating, similar to inert substrates but with the advantage of being easily removable. It provides a stable base for catalyst layer formation and is subsequently removed, simplifying the overall process compared to traditional transfer methods requiring multiple substrates.
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 method effectively prevents wrinkles and cracks, ensures high-quality catalyst coated membranes with excellent performance, and can be executed without requiring advanced technology, facilitating the production of catalyst coated membranes for applications like membrane electrode assemblies.
Implementation Method 1
providing a second side of a membrane with a support film
Implementation Method 2
drying the first catalyst dispersion thereby obtaining a first catalyst coated substrate or drying the second catalyst dispersion coated first side of the membrane thereby obtaining a second catalyst coated first side of the membrane
Implementation Method 3
laminating the first catalyst coated substrate to the second catalyst dispersion coated first side of the membrane or laminating the first catalyst dispersion coated substrate to the second catalyst coated first side of the membrane so that the first catalyst and the second catalyst superimpose
Data Source
AI summary
The present invention concerns a method for preparing a catalyst coated membrane including the steps of:coating a substrate with a first catalyst dispersion thereby obtaining a first catalyst dispersion coated substrate,providing a second side of a membrane with a support film,coating a first side of the membrane with a second catalyst dispersion, thereby obtaining a second catalyst dispersion coated first side of the membrane,drying the first catalyst dispersion thereby obtaining a first catalyst coated substrate or drying the second catalyst dispersion coated first side of the membrane thereby obtaining a second catalyst coated first side of the membrane,laminating the first catalyst coated substrate to the second catalyst dispersion coated first side of the membrane or laminating the first catalyst dispersion coated substrate to the second catalyst coated first side of the membrane so that the first catalyst and the second catalyst superimpose, thereby forming a laminate including a membrane comprising a first catalyst layer,drying the laminate,removing the support film from the second side of the membrane,coating a third catalyst dispersion on the second side of the membrane,drying the third catalyst dispersion, thereby obtaining a second catalyst layer on the membrane, andremoving the substrate from the first catalyst coated substrate.