Battery Cell Tab Layout to Prevent False Welding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The issue of false welding between tabs in battery cells leads to increased internal resistance and instability in battery performance, particularly when tabs with the same polarity are connected to an adapter, causing mutual insertion and resulting in performance degradation.
Innovation Solution
The battery cell design includes a first and second electrode assembly with tabs arranged such that their welding portions are misaligned and staggered when connected to a common connector, reducing the risk of mutual insertion and eliminating the need for pre-welding cutting, thereby enhancing assembly efficiency and reducing production costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If tabs with the same polarity are connected to a common connector, then the space occupied by tabs is reduced and energy density is improved, but false welding occurs due to mutual insertion of tabs
Solution Approach 1:
The patent applies asymmetry by designing the welding portions of tabs with different widths. Specifically, the welding portion of the first tab has a different width than the welding portion of the second tab, creating an asymmetric configuration that prevents mutual insertion while allowing both tabs to connect to the same connector. This asymmetric design eliminates false welding risks while maintaining space efficiency.
Solution Approach 2:
The patent applies local quality by making different parts of the tab structure have different properties. The welding portions of the tabs are designed with different widths locally, while other parts of the tabs maintain standard dimensions. This localized differentiation at the welding portion prevents mutual insertion without affecting the overall tab function or requiring changes to the entire tab structure.
2Volume of moving object
If tabs are bent after connection to reduce space, then energy density is improved, but the complexity of the connection structure increases
Solution Approach 1:
The patent applies preliminary action by pre-designing the asymmetric welding portions on the tabs before connection. The different widths are incorporated into the tab structure in advance, so that when the tabs connect to the common connector, the misalignment is already built-in. This eliminates the need for post-connection bending or additional alignment steps, reducing structural complexity while achieving space reduction.
3Reliability
If pre-welding cutting is performed to prevent false welding, then welding stability is improved, but manufacturing time and cost increase
Solution Approach 1:
The patent applies the taking out principle by removing the need for pre-welding cutting operations. Instead of cutting the tabs to different lengths, the invention extracts the length modification and replaces it with width differentiation at the welding portions. This eliminates the cutting step entirely, maintaining welding stability through asymmetric width design while preserving manufacturing efficiency.
Solution Approach 2:
The patent applies parameter changes by shifting from modifying the length parameter of tabs (through cutting) to modifying the width parameter at the welding portions. This parameter substitution allows the prevention of false welding through dimensional differentiation without requiring material removal or additional processing steps, thereby maintaining productivity while improving reliability.
Data Source
AI summary
A battery cell includes: a first electrode assembly, including a first body and a first tab; a second electrode assembly, including a second body and a second tab, where the first body and the second body are arranged in a first direction; and a first connector, where the first connector is located on one side of the first electrode assembly and the second electrode assembly in a second direction, the second direction is perpendicular to the first direction, and a welding portion of the first tab and a welding portion of the second tab are both connected to the first connector; and in the first direction, a projection of the welding portion of the first tab and a projection of the welding portion of the second tab do not overlap at least in part.