Secondary Battery Mechanical Assembly Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional inner packs for secondary batteries face challenges in assembly and disassembly due to molding processes, leading to high defect rates and structural integrity issues, as well as misalignment and irregular surface irregularities caused by non-uniform resin injection and shrinkage.
Innovation Solution
A mechanical assembly structure for secondary batteries using separately manufactured cases with lead tabs and insulating layers, allowing for easy assembly, disassembly, and rework, while reducing defect rates and maintaining structural integrity through double-sided tape coupling and insert injection molding of the protective circuit module.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If molding resin is used to connect the bare cell with the protective circuit module (PCM), then the inner pack structure is formed, but the assembly process becomes troublesome and difficult to rework
Solution Approach 1:
The patent divides the connection structure into separate components: a case that mechanically holds both the bare cell and PCM, with lead tabs that provide electrical connection. This segmentation allows the bare cell and PCM to be independently positioned and connected without requiring integral molding, enabling easy disassembly and reassembly while maintaining structural integrity.
Solution Approach 2:
The patent introduces a case as an intermediary component that mechanically connects the bare cell and PCM, replacing the direct resin bonding approach. The case serves as a mediator that provides both mechanical support and electrical connection pathways through lead tabs, allowing for easy separation and reassembly without damaging the connected components.
2Manufacturing precision
If molding resin is injected to connect the bare cell and PCM, then the inner pack is formed, but the injection process requires high accuracy and causes non-uniform injection
Solution Approach 1:
The patent extracts the connection function from the molding resin injection process and transfers it to a mechanical assembly using a case and lead tabs. This eliminates the need for high-precision resin injection into tight spaces between the bare cell and PCM, thereby reducing defects caused by non-uniform injection while maintaining manufacturing precision.
Solution Approach 2:
The patent replaces the chemical/bonding mechanism of molding resin with a mechanical connection system consisting of a case and lead tabs. This substitution eliminates the complexities of resin injection control and eliminates defects related to non-uniform resin distribution, while improving overall productivity by simplifying the assembly process.
3Reliability
If molding resin is used to connect the bare cell with the PCM, then the inner pack is formed, but the molding resin cannot be recovered and increases processing difficulty
Solution Approach 1:
The patent enables recovery and reuse of the connection components. The case and lead tabs can be disassembled from the bare cell and PCM, allowing for recovery of these components for potential reuse. This eliminates the waste of molding resin and reduces processing difficulty by allowing rework and adjustment during manufacturing.
4Manufacturing precision
If molding resin is injected at high pressure, then the core pack is formed, but the high pressure disturbs the arrangement of the bare cell and PCM
Solution Approach 1:
The patent replaces the high-pressure resin injection system with a low-pressure mechanical assembly system. The case and lead tabs are positioned and fixed using gentle mechanical means such as adhesives or clips, eliminating the high pressure that would disturb the arrangement of the bare cell and PCM, while maintaining precise arrangement accuracy.
Data Source
AI summary
A secondary battery capable of assembling a bare cell and a protective circuit module (PCM) in a manner of mechanical connection without performing a molding is provided. The secondary battery includes a bare cell whose top surface is provided with an electrode terminal having a polarity, a first case covering the top surface of the bare cell, a second case covering a first side surface of the bare cell, a first lead tab coupling the electrode terminal to the PCM, and a second lead tab coupling a surface of the bare cell having another polarity to the protective circuit module. Both of the first and the second lead tabs are covered by the first case.