Electrochemical Cell Stack Interconnector Recessed Portion Thermal Expansion

Solution Overview

Problem

In electrochemical reaction cell stacks, such as fuel cell and electrolysis cell stacks, the protruding portions of electrically conductive members can interfere with each other, leading to sealing issues and thermal expansion-related problems, which affect the stack's performance and durability.

Innovation Solution

The electrochemical reaction cell stack design incorporates electrically conductive members with recessed portions that are deeper than the protruding portions, ensuring reduced interference and maintaining structural strength, with specific thickness and depth ratios to minimize thermal expansion issues and corrosion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If electrically conductive members are stacked with protruding portions, then electrical conductivity and structural support are improved, but interference between adjacent members occurs leading to sealing deterioration

Engineering Contradiction:

Improvestructural supportVSAvoidsealing

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The recessed portion is designed in advance to counteract the interference caused by thermal expansion of the protruding portion. By creating a space (recessed portion) that accommodates the expected expansion of the protruding portion, the design prevents sealing deterioration before it occurs during operation.

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The recessed portion acts as a cushioning space that absorbs the dimensional changes due to thermal expansion. This beforehand cushioning design allows the protruding portion to expand without compromising the sealing between adjacent electrically conductive members.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Strength

If the thickness of electrically conductive members is increased to improve structural strength, then thermal expansion increases causing greater interference with adjacent members

Engineering Contradiction:

Improvestructural strengthVSAvoidthermal expansion interference

Core Design Contradiction:

StrengthVSObject-affected harmful factors

Solution Approach 1:

The recessed portion is designed in advance to counteract the interference caused by thermal expansion of the protruding portion. By creating a space (recessed portion) that accommodates the expected expansion of the protruding portion, the design prevents sealing deterioration before it occurs during operation.

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The design changes the geometric parameters of the electrically conductive members by introducing recessed portions with specific dimensions. The depth and width of the recessed portion are carefully controlled to accommodate thermal expansion while maintaining structural strength and proper sealing.

Inventive Principle:

Principle #35Parameter changes

3Area of stationary object

If protruding portions are made longer to improve contact area, then interference with adjacent members increases and corrosion risk increases

Engineering Contradiction:

Improvecontact areaVSAvoidcorrosion

Core Design Contradiction:

Area of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The design optimizes the parameters of the protruding and recessed portions to achieve the right balance. The protruding portion has sufficient length to provide adequate contact area for electrical conductivity and mechanical support, while the recessed portion provides enough clearance to prevent excessive interference and reduce corrosion risk.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The recessed portion is designed in advance to counteract the interference caused by thermal expansion of the protruding portion. By creating a space (recessed portion) that accommodates the expected expansion of the protruding portion, the design prevents sealing deterioration before it occurs during operation.

Inventive Principle:

Principle #9Preliminary anti-action

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 design effectively prevents interference between adjacent electrically conductive members due to thermal expansion, maintains structural integrity, and reduces corrosion, thereby enhancing the stack's performance and longevity.

Implementation Method 1

the larger the thickness in the first direction, the larger the amount of thermal expansion. Therefore, the thermally expanded recessed portion of an electrically conductive member with a large thickness is more likely to interfere with the protruding portion of another electrically conductive member

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS11271221B2Electrochemical reaction cell stack, interconnector-electrochemical reaction unit cell composite, and method for manufacturing electrochemical reaction cell stack

Publication Date: 2022.03.08 NITERRA CO LTD

AI summary

An electrochemical reaction cell stack including a plurality of unit cells and flat plate-shaped electrically conductive members arranged in a first direction. The electrically conductive members include: a first member having a first surface including a first flat portion and a protruding portion and a second member both located on the first side of the first member in the first direction, the second member having a second surface facing the first surface and including a second flat portion and a recessed portion facing the protruding portion. The thickness of the second member is larger than the thickness of the first member in the first direction. The depth of the recessed portion of the second member from the second flat portion is larger than the protruding length of the protruding portion of the first member from the first flat portion in the first direction.