Laser Welding Sealed Battery With Segmented Beads
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for continuous laser welding of sealed batteries face issues with fumes interfering with the laser beam, leading to insufficient weld penetration and increased processing time, as the laser beam is diffused or reflected by fumes generated during the welding process.
Innovation Solution
A method involving the formation of spaced-apart first weld beads and subsequent second weld beads in the gaps between them, with specific length ranges for both types of weld beads to minimize fume interference, ensuring adequate melting depth and reducing processing time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If continuous welding is performed with a laser beam, then welding efficiency is improved, but fumes are generated that interfere with the laser beam, causing insufficient melting depth
Solution Approach 1:
The continuous weld is divided into multiple discrete weld beads with specific spacing. The first weld beads are formed with spacing to allow fume dispersion, and second weld beads fill the gaps. This segmentation prevents fume accumulation along the weld path while maintaining continuous weld coverage, resolving the contradiction between welding efficiency and melting depth.
Solution Approach 2:
The welding process uses periodic pulsed laser emission rather than continuous emission. The laser is emitted in pulses with intervals that allow fume dispersion, preventing fume interference with the laser beam while maintaining adequate melting depth through controlled energy input.
2Reliability
If laser scanning is performed with overlap to ensure coverage, then welding completeness is improved, but fume accumulation increases, affecting laser beam penetration
Solution Approach 1:
The weld is segmented into first weld beads with spacing equal to or greater than the weld bead length, eliminating overlap. Second weld beads are then formed to fill the gaps between first weld beads. This approach ensures complete weld coverage without creating overlapping regions where fumes would accumulate and interfere with the laser beam.
3Object-affected harmful factors
If pulsed laser emission is used to allow fume diffusion, then fume interference is reduced, but processing time increases significantly
Solution Approach 1:
The weld is divided into spaced first weld beads followed by second weld beads in the gaps. This segmentation allows fume dispersion between beads without requiring long pauses, as the laser moves continuously between beads. The spacing is optimized to allow fume clearance while minimizing total processing time.
Solution Approach 2:
The laser welding process continues without interruption, moving from one weld bead to the next in sequence. There are no stops or pauses between beads, maintaining continuous useful action. The spaced configuration allows fume dispersion during the laser's movement between beads, eliminating the need for time-consuming pauses.
4Device complexity
If weld bead length is increased to reduce number of beads, then processing steps are reduced, but fume generation increases, affecting laser penetration
Solution Approach 1:
The total weld is segmented into multiple shorter first weld beads with spacing, followed by second weld beads in the gaps. This segmentation reduces fume generation per bead while ensuring complete coverage. The spacing between first weld beads is equal to or greater than their length, preventing fume accumulation that would occur with longer continuous welds.
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 approach effectively suppresses fume interference, allowing for the formation of welds with excellent penetration depth while maintaining a reduced processing time by optimizing the length and spacing of weld beads.
Implementation Method 1
forming a welded portion connecting an opening edge portion of the case body and an outer peripheral edge portion of the lid
Implementation Method 2
a sufficient melting depth cannot be obtained
Implementation Method 3
fumes are generated from a welded part, and the laser beam may interfere with particles of the fumes
Data Source
AI summary
A method of manufacturing a sealed battery includes a welding step of forming a welded portion, and the welding step includes a first step of sequentially forming a plurality of weld beads in an opening edge portion and an outer peripheral edge portion such that the plurality of weld beads are spaced apart from one another, and a second step of forming a weld bead in each gap portion located between the weld beads, with a plurality of gap portions being formed in the opening edge portion and the outer peripheral edge portion.