Laser Welded Sealing Patch for Battery Fill Hole
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for sealing the electrolyte fill hole in battery cells often compromise the structural integrity of the housing, leading to electrolyte leakage and contamination due to cracks formed during the sealing process.
Innovation Solution
A lithium-ion battery cell design featuring a sealing patch laser welded to the casing around the electrolyte fill hole, with a partial penetration weld to minimize crack formation and a pre-ablation process to remove residue and contaminants, ensuring a secure seal without compromising the housing's integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional sealing methods are used to seal the electrolyte fill hole, then the fill hole is sealed, but cracks form in the housing compromising structural integrity
Solution Approach 1:
The sealing function is segmented from the housing structure by introducing a separate sealing patch that is welded to the housing. This separates the sealing requirement from the structural integrity requirement, allowing the housing to maintain its strength while the sealing patch provides the seal without compromising the housing structure.
Solution Approach 2:
The sealing patch acts as an intermediary element between the electrolyte fill hole and the housing. It mediates the sealing function while the housing maintains its structural integrity, preventing direct compromise of the housing strength during the sealing process.
2Reliability
If deep penetration welding is used to seal the patch, then the seal is secure, but cracks form in the housing reducing structural integrity
Solution Approach 1:
Instead of using full penetration welding, the patent employs partial penetration welding where the weld depth is controlled to be less than the full thickness of the housing wall. This provides sufficient sealing security while avoiding excessive heat input that would cause cracks and compromise housing strength.
3Ease of manufacture
If laser welding is used without pre-ablation, then the process is simpler, but residue and contaminants remain affecting seal quality
Solution Approach 1:
A pre-ablation step is performed before the welding process to remove residue and contaminants from the sealing surface. This preliminary cleaning action ensures high seal quality by eliminating contaminants that would otherwise interfere with the welding and sealing process.
Solution Approach 2:
The manual or mechanical cleaning methods are replaced with laser ablation, which uses focused laser energy to precisely remove contaminants and residue from the sealing surface. This substitution provides superior cleaning precision while maintaining process automation.
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
The solution effectively reduces electrolyte leakage and contamination by minimizing crack formation and enhancing the seal's reliability, maintaining the structural integrity of the battery cell housing.
Implementation Method 1
a sealing patch laser welded to the casing around the electrolyte fill hole
Implementation Method 2
a pre-ablation process to remove residue and contaminants
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A lithium-ion battery cell includes an enclosure that includes a casing and a lid. The enclosure has an electrolyte fill hole disposed on a surface of the casing opposite the lid. An electrochemical cell is disposed within the enclosure. Additionally, a sealing patch is laser welded to the surface of the casing around the electrolyte fill hole, wherein the sealing patch is configured to seal the electrolyte fill hole.