Solid Oxide Fuel Cell Gel Cast Process Warping Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing manufacturing method for solid oxide fuel cells (SOFCs) results in increased electric resistance and limited design freedom for fuel channels due to large particle sizes and susceptibility to warping, leading to reduced output density and potential damage during the sintering process.
Innovation Solution
The method involves using a gel cast process with ceramic slurry containing ceramic powder, dispersion media, and a gelling agent to form compacts with smaller primary particles, allowing for increased contact area and reduced warping by accommodating the support-member divided-member in a different molding die for forming the solid electrolyte and fuel-side electrode, thereby enhancing electrical connection and design flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If press molding with secondary particles is used to form the support member, then the degree of freedom in fuel channel shape is increased, but the particle size becomes large (about 80 μm) resulting in reduced contact area and increased electric resistance
Solution Approach 1:
The invention changes the particle size parameter from large secondary particles (about 80 μm) to fine primary particles (about 1-10 μm) by using spray-dried powder instead of granular secondary particles in the press molding process. This parameter change increases the contact area between the support member and fuel-side electrode, thereby reducing electric resistance and improving electrical connection quality while maintaining the ability to form complex fuel channel shapes.
2Adaptability or versatility
If two compacts of support-member divided-member are bonded before sintering, then complicated fuel channel shapes can be formed, but the unbonded compact is susceptible to warping and cracking during subsequent processing
Solution Approach 1:
The invention applies preliminary sintering to the bonded compact of support-member divided-members before forming the fuel-side electrode and solid electrolyte compacts. This preliminary sintering action strengthens the bonded compact, preventing warping and cracking during subsequent handling and processing steps, while still allowing the formation of complicated fuel channel shapes through the bonded divided-members.
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
This approach reduces the electric resistance of the SOFCs, increases output density, and prevents warping of the support member, resulting in a more efficient and robust fuel cell with improved electrical performance and design flexibility.
Implementation Method 1
a gel cast process with ceramic slurry containing ceramic powder, dispersion media, and a gelling agent to form compacts with smaller primary particles
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A compact of a support-member divided-member, which has a shape formed by dividing a support member into two in the thickness direction so as to divide the fuel channel into two in the thickness direction, is manufactured by a gel cast method in which slurry is filled in a molding die. A compact of a fuel-side electrode and a compact of an electrolyte are successively stacked on the upper surface of the compact of the support-member divided-member, whereby a compact of a cell divided member is obtained. The two compacts of the cell divided member are bonded and sintered, whereby an SOFC cell (sintered body) in which an oxygen-side electrode is not formed is formed. A compact of the oxygen-side electrode is formed respectively on the upper and lower surfaces of the sintered body, and then, the compact of the oxygen-side electrode is sintered, whereby the SOFC cell is completed.