Fuel Cell Bus Bar Joint Structure for Thermal Expansion Matching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fuel cell modules face challenges in maintaining stable electrical connections and reducing thermal stress on joint parts due to mismatched thermal expansion coefficients between components, leading to potential abrasion and increased resistance.
Innovation Solution
The fuel cell module design incorporates joint parts with a linear expansion coefficient equal to or less than the bus bar, using materials like ferritic stainless steel for terminals and joint parts, and austenite stainless steel for external connections, along with insulation parts to manage thermal expansion and reduce stress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If joint parts with mismatched thermal expansion coefficients are used to connect terminal and bus bar, then electrical connection is established, but thermal stress and abrasion increase during temperature changes
Solution Approach 1:
The patent changes the material parameter (linear expansion coefficient) of the joint part to be equal to or less than that of the bus bar. This parameter adjustment ensures that during temperature changes, the joint part and bus bar expand and contract at compatible rates, reducing thermal stress and abrasion while maintaining reliable electrical connection.
Solution Approach 2:
The patent applies homogeneity by matching the linear expansion coefficients of the joint part and bus bar. When materials have similar thermal expansion properties, they undergo uniform dimensional changes during temperature fluctuations, minimizing relative movement and thermal stress at the joint interface.
2Reliability
If materials with different linear expansion coefficients are used for terminal and bus bar, then electrical connection is achieved, but gaps and abrasion occur during thermal cycling
Solution Approach 1:
The patent modifies the material parameter (linear expansion coefficient) of the joint part to match or exceed that of the bus bar. This ensures synchronized thermal expansion behavior, preventing gap formation and abrasion during thermal cycling while maintaining stable electrical connection.
3Ease of manufacture
If conventional materials are used for joint parts, then manufacturing is simplified, but thermal stress concentration occurs during operation
Solution Approach 1:
The patent selects materials for the joint part with specific linear expansion coefficient parameters that are equal to or less than the bus bar material. This parameter optimization reduces thermal stress concentration during operation while remaining compatible with conventional manufacturing processes.
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 minimizes gaps and abrasion, eases thermal stress, and maintains efficient power output by reducing the difference in expansion and contraction between components, thereby enhancing the durability and performance of the fuel cell module.
Implementation Method 1
A linear expansion coefficient of the first joint part is equal to or less than a linear expansion coefficient of the bus bar
Implementation Method 2
minimizes gaps and abrasion, eases thermal stress, and maintains efficient power output by reducing the difference in expansion and contraction between components
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A fuel cell module includes a fuel cell stack, a terminal, a bus bar, a first joint part, the first joint part, and a container. The terminal is configured to output electric power generated by the fuel cell stack. The bus bar is coupled to the terminal. The first joint part 14 joins the terminal and the bus bar to one another. A second joint part joins the bus bar to an external conductor at a position of the bus bar different from a position joined to the terminal. A linear expansion coefficient of the first joint part is equal to or less than a linear expansion coefficient of the bus bar.