Laser Tab-to-Can Welding with Index Table Motion Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing secondary battery manufacturing methods, particularly resistance welding, suffer from high failure rates and difficulty in detecting defects, especially in connecting electrode tabs to battery cans.
Innovation Solution
An apparatus using a laser scanner controlled by a controller that adjusts its operation based on the rotation rate of an index table to ensure precise welding of electrode tabs to battery cans, employing a combination of motors and encoders to maintain consistent welding patterns despite variations in table speed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If resistance welding method is used to bond electrode tab to can, then welding process can be performed, but welding quality is inconsistent and defect detection is difficult
Solution Approach 1:
The patent replaces the mechanical resistance welding system with a laser-based welding system. The laser welding apparatus uses optical energy instead of mechanical pressure and electrical current to join the electrode tab to the can, eliminating the inconsistencies and detection difficulties associated with resistance welding while maintaining reliable welding quality
2Reliability
If laser scanner is used to weld electrode tab to can, then welding quality improves, but system complexity increases
Solution Approach 1:
The laser scanner is designed to perform multiple functions: it scans the welding area, delivers precise laser energy for welding, and can integrate with detection systems. This multi-functionality reduces the need for separate devices, thereby managing system complexity while maintaining improved welding quality
Solution Approach 2:
The patent introduces a controller as an intermediary that coordinates between the laser scanner, motion control systems, and detection apparatus. This centralized control simplifies the overall system architecture by managing complex interactions through a single coordinating unit, reducing the burden on individual components
3Productivity
If index table rotation rate varies during welding, then production flexibility increases, but welding pattern consistency deteriorates
Solution Approach 1:
The patent implements dynamic control where the laser scanning speed and indexing table rotation are continuously coordinated. The system adjusts the laser scanner's operation in real-time based on the actual rotation rate of the index table, ensuring consistent welding patterns even when production speed varies. This dynamic synchronization maintains manufacturing precision while allowing production flexibility
Solution Approach 2:
The system incorporates feedback mechanisms that monitor the index table rotation rate and use this information to adjust laser scanning parameters. This closed-loop control ensures that welding pattern consistency is maintained by continuously adapting to changes in rotation rate, thereby preserving precision while enabling flexible production rates
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
Improves welding quality and accuracy by adapting laser scanner operations in real-time to table motion, ensuring consistent and defect-free connections between electrode tabs and cans.
Implementation Method 1
a laser scanner configured to irradiate a laser onto an outer surface of the can to weld the electrode tab to the can
Data Source
Figure 1~2
Figure 3
Figure 4~5a
AI summary
An apparatus for manufacturing a secondary battery includes: an index table configured to receive a secondary battery cell, the secondary battery cell including an electrode assembly, a can accommodating the electrode assembly, and an electrode tab between the electrode assembly and the can to electrically connect the electrode assembly to the can; a laser scanner configured to irradiate a laser onto an outer surface of the can to weld the electrode tab to the can; and a controller configured to variably control the laser scanner according to an operation of the index table.