Fuel Cell Stack Thermal Deformation Absorbing Mechanism

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Fuel cell stacks experience deformation and performance degradation due to thermal expansion, leading to gas leaks and load loss during temperature changes, which existing technologies fail to adequately address.

Innovation Solution

A fuel cell stack structure featuring alternately stacked power generation cells and separators, fixed to end plates with a thermal deformation absorbing mechanism, including a space between stacked rows and adjustable fastening forces to manage thermal expansion orthogonally, preventing contact and deformation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If gas is supplied at high velocity or high temperature to the fuel cell, then power generation efficiency is improved, but thermal deformation occurs in stacked members causing gas leaks and performance degradation

Engineering Contradiction:

Improvepower generation efficiencyVSAvoidgas seal integrity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent introduces a thermal deformation absorbing portion that changes its physical state or dimensions in response to temperature variations. This component is designed to expand or contract thermally, thereby absorbing the thermal deformation that would otherwise be transmitted to the stacked members and sealing portions, maintaining gas seal integrity even under high temperature operation

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The thermal deformation absorbing portion acts as an intermediary element between the end plate and the stacked members. It mediates the thermal stress by absorbing the deformation through its own material properties or structural design, preventing direct transmission of thermal forces to the sealing portions and maintaining reliable operation

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If gas is supplied at high velocity or high temperature to the fuel cell, then power generation efficiency is improved, but load applied to stacked members causes deformation

Engineering Contradiction:

Improvepower generation efficiencyVSAvoidstacked members deformation

Core Design Contradiction:

ProductivityVSShape

Solution Approach 1:

The thermal deformation absorbing portion is designed with specific material properties or structural characteristics that allow it to undergo controlled dimensional changes in response to thermal loading. This parameter change absorbs the thermal expansion or contraction forces, preventing deformation of the stacked members while allowing high temperature gas flow for efficient power generation

Inventive Principle:

Principle #35Parameter changes

3Stability of the object's composition

If fixing means is used to secure stacked bodies to end plate, then structural stability is improved, but thermal deformation is restrained causing stress concentration

Engineering Contradiction:

Improvestructural stabilityVSAvoidthermal stress

Core Design Contradiction:

Stability of the object's compositionVSStress or pressure

Solution Approach 1:

The thermal deformation absorbing portion is designed to undergo controlled parameter changes (dimensional expansion or contraction) in response to thermal loading. This allows the structure to maintain stability through the fixing means while the absorbing portion accommodates thermal stress through its own deformation, preventing stress concentration that would lead to failure

Inventive Principle:

Principle #35Parameter changes

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 effectively reduces deformation and maintains performance by absorbing thermal expansion, preventing gas leaks and load loss, and ensuring stable operation across temperature variations.

Implementation Method 1

a first thermal deformation absorbing portion configured to absorb thermal deformation in a direction orthogonal to a stacking direction is formed between the stacked bodies

Methodology Applied

Scientific EffectThermal deformation: Thermal Expansion

Data Source

PatentUS11495822B2Stack structure of fuel cell and method of absorbing thermal deformation in fuel cell stack

Publication Date: 2022.11.08 NISSAN MOTOR CO LTD

AI summary

Stacked bodies each formed by alternately stacking power generation cells and separators are fixed to an end plate, the separators each having a flow passage portion, a gas flow-in port, and a gas flow-out port. The end plate includes upper and lower end plates sandwiching the stacked bodies. The stacked bodies are arranged side by side and a first thermal deformation absorbing portion configured to absorb thermal deformation in a direction orthogonal to a stacking direction is formed between the stacked bodies. Fixing means for fixing the stacked bodies to the end plate fix at least outer peripheral portions of the stacked bodies arranged side by side to the end plate.