Fuel Cell Assembly Fixing and Sealing Members

Solution Overview

Problem

Conventional fuel cell assemblies require complex fixing structures to maintain firm fixation and reliable gas tightness at high temperatures, but existing solutions either crack when cooled or soften during operation, compromising gas tightness.

Innovation Solution

A fuel cell assembly where the ends of cells are fixed to a holding means using a combination of a fixing member with a softening temperature above 1000°C and a sealing member with a softening temperature between 700°C to 1000°C, both having distinct thermal expansion coefficients, ensuring reliable gas-tight sealing without exposure to the electricity generation chamber.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a fixing and sealing member with high softening temperature is used, then firm fixing is achieved, but cracks occur during cooling causing gas tightness impairment

Engineering Contradiction:

Improvefirm fixingVSAvoidgas tightness

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The patent divides the single fixing and sealing member function into two separate members: a fixing member (54) responsible for firm mechanical fixation and a sealing member (56) responsible for gas-tight sealing. This segmentation allows each member to be optimized for its specific function without the conflicting requirements that cause cracking in single-material solutions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs composite material strategy by combining two different materials with complementary properties: a high-softening-temperature material for fixing and a low-softening-temperature material for sealing. This composite approach resolves the contradiction by allowing each material to operate in its optimal temperature range without experiencing the thermal stress conflicts that cause cracking.

Inventive Principle:

Principle #40Composite materials

2Reliability

If a fixing and sealing member with low softening temperature is used, then gas tightness is maintained, but the member softens during operation causing poor fixing

Engineering Contradiction:

Improvegas tightnessVSAvoidfirm fixing

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent divides the single fixing and sealing member function into two separate members: a fixing member (54) responsible for firm mechanical fixation and a sealing member (56) responsible for gas-tight sealing. This segmentation allows each member to be optimized for its specific function without the conflicting requirements that cause softening issues.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs composite material strategy by combining two different materials with complementary properties: a high-softening-temperature material for fixing and a low-softening-temperature material for sealing. This composite approach resolves the contradiction by allowing each material to operate in its optimal temperature range without compromising either fixing strength or gas tightness.

Inventive Principle:

Principle #40Composite materials

3Reliability

If a complex fixing structure is used, then both firm fixing and gas tightness are maintained, but the structure becomes overly complicated

Engineering Contradiction:

Improvegas tightness and firm fixingVSAvoidfixing structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent divides the single fixing and sealing member function into two separate members: a fixing member (54) responsible for firm mechanical fixation and a sealing member (56) responsible for gas-tight sealing. This segmentation allows each member to be optimized for its specific function without the conflicting requirements that cause cracking in single-material solutions.

Inventive Principle:

Principle #1Segmentation

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 allows for robust, reliable gas-tight fixation of fuel cell ends at high temperatures, preventing cracking and softening issues, thus maintaining efficient operation and longevity of the fuel cell assembly.

Implementation Method 1

the fixing member and the sealing member having properties different from each other... the fixing member has a softening temperature of not lower than 1000°C and the sealing member has a softening temperature of from 700 to 1000°C

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS8026011B2Fuel cell assembly

Publication Date: 2011.09.27 KYOCERA CORP

AI summary

A fuel cell assembly in which ends on one side of the cells forming gas passages are gas-tightly fixed to a holding means. Between the peripheries of the ends on one side of the cells and the holding means, there are arranged a fixing member for fixing the cells to the holding means and a sealing member for accomplishing a gas-tight sealing between the ends on one side of the cells and the holding means. The fixing member has a softening temperature of not lower than 1000° C. and the sealing member has a softening temperature of from 700 to 1000° C.