Flexible Copper Busbar Convex Structure for Shock Fatigue Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flexible copper busbars in power batteries face challenges in reliability and fatigue life due to stress concentration and contact resistance changes under harsh working conditions, particularly during vibrations or shocks, which are difficult to model accurately using CAE analysis.
Innovation Solution
A method and apparatus for designing a flexible copper busbar with a convex portion between connection portions, utilizing finite element grid modeling to analyze mechanical shock and determine the total length of the busbar, ensuring no force transmission and uniform stress distribution, thereby increasing fatigue life and contact resistance stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If CAE analysis is performed on the flexible copper busbar to ensure reliability, then the stress analysis can be conducted, but the modeling difficulty increases significantly due to the multi-layer thin sheet copper structure
Solution Approach 1:
The flexible copper busbar is divided into three distinct segments: a first connection portion, a convex portion, and a second connection portion. This segmentation simplifies the CAE modeling process by allowing each segment to be analyzed independently with appropriate boundary conditions, rather than modeling the entire complex multi-layer structure as a single unit.
Solution Approach 2:
The convex portion is designed with a curved geometry instead of a flat plate structure. This curvature allows the busbar to flex and deform under stress without creating stress concentration points, thereby maintaining reliability while simplifying the mechanical behavior prediction in CAE analysis.
2Ease of manufacture
If a flat plate structure is used for the flexible copper busbar, then the manufacturing is easy, but the busbar is easy to be stretched in harsh working conditions which decreases fatigue life
Solution Approach 1:
The convex portion with curved geometry replaces the traditional flat plate structure. The curved shape provides inherent flexibility that allows the busbar to accommodate thermal expansion and mechanical deformation without stretching or permanent deformation, thereby extending fatigue life while maintaining ease of manufacture through standard forming processes.
Solution Approach 2:
The design changes the geometric parameters of the busbar by introducing a convex portion with specific curvature radius and dimensions. This parameter change transforms the mechanical properties of the busbar, enabling it to resist stretching and fatigue while remaining manufacturable using conventional processes.
3Reliability
If the flexible copper busbar is designed to accommodate space changes between battery modules, then the contact resistance stability is improved, but the busbar structure becomes more complex
Solution Approach 1:
The busbar is segmented into connection portions and a convex portion, where the convex portion specifically handles the accommodation of space changes. This segmentation allows the connection portions to maintain simple, reliable connection structures while the convex portion absorbs dimensional variations, thereby maintaining contact resistance stability without overall structural complexity.
Solution Approach 2:
The convex portion acts as an intermediary element between the first and second connection portions. It mediates the mechanical stresses and dimensional changes from the battery modules, protecting the connection portions from direct stress exposure and maintaining stable electrical contact without requiring complex connection structures.
Data Source
Figure 1
Figure 2~4
Figure 5~6
AI summary
The invention provides a flexible copper busbar and a method and apparatus for designing a flexible copper busbar of a power battery, which belong to the field of power battery. The flexible copper busbar comprises a first connection portion, a second connection portion and a convex portion connected between the first connection portion and the second connection portion. In harsh working conditions, the convex portion is stretched under a force to become straightened, stress is distributed uniformly without stress concentration, and there is no force transmission. Fatigue life and contact resistance stability of the flexible copper busbar can be increased. In the method and apparatus for designing the flexible copper busbar, by analyzing the maximum space between first and second battery modules which are connected with opposite ends of the flexible copper busbar and then determining the total length of the flexible copper busbar, a procedure of investigating the stress by modeling the flexible copper busbar is avoided, and power battery designing efficiency can be increased.