Rectangular Battery Lid Support and Laser Welding Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for welding the lid and main body members of rectangular batteries face challenges such as laser beam penetration through gaps, which can damage the electrode body, and difficulties in maintaining consistent shoulder portions for proper support and welding.
Innovation Solution
The battery design incorporates support projecting portions and low projecting portions within the opening portions of the main body member to securely position the lid and prevent laser beam entry, using energy beams for welding while maintaining clearances to avoid direct penetration and ensure reliable sealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If projections are formed at the four opening corners to prevent lid dropping, then lid support is improved, but laser beam may enter through clearance and damage electrode body
Solution Approach 1:
The opening portion is segmented into multiple regions: four corner regions with support projecting portions for lid support, and side regions with low projecting portions for laser beam blocking. This segmentation allows each region to perform its specific function independently, resolving the contradiction between lid support and laser beam protection.
Solution Approach 2:
Different regions of the opening portion are given different structural qualities: corner regions have support projecting portions extending higher to support the lid, while side regions have low projecting portions extending lower to block laser beams. This local differentiation allows simultaneous achievement of lid support and laser beam blocking functions.
2Reliability
If shoulder portions are formed in the opening portion to support the lid, then lid support is improved, but it is difficult to maintain consistent position in depth direction
Solution Approach 1:
The support function is segmented and concentrated at the four corner regions where support projecting portions are formed. By focusing support at discrete corner points rather than continuous shoulder portions, the structure achieves reliable lid support while simplifying manufacturing and improving position consistency.
3Reliability
If engagement piece is provided around the lid, then lid support is improved, but laser beam irradiation from side makes welding difficult
Solution Approach 1:
Instead of providing engagement pieces around the lid periphery that would block side laser beam access, the invention inverts the approach by providing support projecting portions at corner regions that support the lid from below while allowing side laser beam irradiation for welding. This inversion resolves the contradiction between engagement and welding feasibility.
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 damage to the electrode body by ensuring the laser beam is absorbed or reflected by the projecting portions, maintaining the lid's position for proper welding and enhancing the reliability and cost-effectiveness of the battery manufacturing process.
Implementation Method 1
the opening portion and the lid peripheral edge portion are welded to each other by an energy beam (laser beam)
Implementation Method 2
ensuring the laser beam is absorbed or reflected by the projecting portions
Implementation Method 3
ensuring the laser beam is absorbed or reflected by the projecting portions
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The battery case (110) of this square battery (100) comprises a lid member (113) welded to an opening (111h) in a main body member (111). The opening R section (111r) of the opening (111h) has, in the circumferential direction (SH), a support projection (111e) which projects inward across the entire opening R section (111r) and which supports the lid member (113). Meanwhile, in the circumferential direction (SH) across the entire opening short side (111b), the opening short side (111b) has a low projecting section (111d) which projects inward at a position lower than the support projection (111e) in the depth direction (FH) of the main body member (111).