Ultrasonic Tab Welding Pressure Control for Thickness Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ultrasonic welding devices for secondary batteries often cause deformation and welding defects due to inconsistent pressure application on the overlapping surfaces of electrode tabs and leads, leading to product defects.
Innovation Solution
An ultrasonic welding device with adjustable pressure control mechanisms, including an anvil and horn, measures the thickness of electrode tabs and leads to adjust pressure uniformly, preventing deformation and ensuring consistent welding quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the overlapping surface is pressed with high pressure through the anvil and horn, then welding strength is improved, but the overlapping surface is deformed causing welding defects
Solution Approach 1:
The electrode tab thickness is measured before the welding process using a thickness measuring device. Based on the measured thickness, the pressing force of the horn is preliminarily adjusted to an appropriate level. This preliminary measurement and adjustment prevents surface deformation during welding while ensuring sufficient welding strength, resolving the contradiction between strong welding and surface integrity.
2Reliability
If the pressing force of the horn is increased to ensure constant pressure, then welding quality is improved, but electrode tabs of different thicknesses cannot be accommodated
Solution Approach 1:
The horn pressing force is made dynamically adjustable rather than fixed. A pressure adjusting device modifies the horn's pressing force based on the measured electrode tab thickness. This dynamic adjustment allows the system to adapt to different thicknesses while maintaining constant optimal pressure, ensuring high welding quality across varying electrode tab specifications.
Solution Approach 2:
A feedback control system is implemented where the electrode tab thickness is measured first, then this measurement feedback is used to adjust the horn pressing force before welding. This closed-loop feedback ensures that the pressing force is optimized for each specific electrode tab thickness, maintaining consistent welding quality while accommodating thickness variations.
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 device maintains constant pressure on the overlapping surfaces, preventing deformation and defects, thereby ensuring uniform and high-quality welding of electrode tabs and leads in secondary batteries.
Implementation Method 1
a horn for applying ultrasonic waves to the overlapping surface disposed on the anvil to weld the overlapping surface
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An ultrasonic welding device for a secondary battery, which is configured to weld an overlapping surface of an electrode tab and an electrode lead, which are provided in an electrode assembly, according to the present invention comprises: an anvil on which the overlapping surface of the electrode tab and the electrode lead is disposed; a horn configured to apply ultrasonic waves to the overlapping surface of the electrode tab and the electrode lead, which is disposed on the anvil, while pressing the overlapping surface; an electrode tab measuring part configured to measure a thickness of the electrode tab disposed on the overlapping surface; and a pressure adjusting device configured to adjust a pressure applied to the overlapping surface by the anvil and the horn according to the thickness value of the electrode tab, which is measured by the electrode tab measuring part.