Button Cell Top Plate Fusion Bonding for Thin Leak-Tight Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Button-type secondary batteries face limitations in reducing the thickness of the top plate assembly due to the strong coupling force requirements between the base plate, electrode terminal, and insulating gasket, leading to relatively low energy density and space inefficiency, as well as concerns about gas and electrolyte leakage due to inadequate sealing.
Innovation Solution
A button-type secondary battery design featuring a thermal fusion bonding method between the electrode terminal, insulating gasket, and base plate, with chromate surface treatment and a PP-MAH layer, allowing for a reduced thickness of the top plate assembly while maintaining strong coupling and insulation, and utilizing laser welding and insulating tape for enhanced sealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the positive electrode terminal is coupled to the base plate in the form of a rivet, then the coupling strength between the electrode terminal and base plate is ensured, but the thickness of the top plate assembly cannot be reduced
Solution Approach 1:
The patent replaces the mechanical rivet coupling system with a thermal fusion bonding system. The electrode terminal and base plate are bonded through thermal fusion at the bonding surface, eliminating the need for rivets and through-holes. This substitution allows for a thinner top plate assembly while maintaining strong coupling between components.
Solution Approach 2:
The patent changes the bonding method from mechanical (rivet) to thermal (fusion bonding). By applying heat and pressure to fuse the bonding surfaces of the electrode terminal and base plate, the coupling strength is maintained while the overall thickness is reduced. The chromate surface treatment and PP-MAH layer further enhance the bonding parameters to ensure strong adhesion.
2Quantity of substance
If the thickness of the top plate assembly is reduced, then the energy density and space efficiency are improved, but the coupling strength between components becomes insufficient
Solution Approach 1:
The patent replaces mechanical fastening systems with thermal fusion bonding, allowing for reduced component thickness while maintaining coupling strength. The thermal fusion process creates a strong bond between the electrode terminal and base plate without requiring thick structural elements for mechanical fastening.
Solution Approach 2:
The patent employs composite material structures including chromate surface treatment layers and PP-MAH (polypropylene-maleic anhydride) layers at the bonding interfaces. These composite material systems enhance the bonding strength between components, allowing for thinner overall assembly while maintaining sufficient coupling strength for high energy density applications.
3Ease of manufacture
If the bonding surface between the base plate, electrode terminal, and gasket is not adequately sealed, then the manufacturing process is simplified, but gas and electrolyte leakage occurs
Solution Approach 1:
The patent replaces mechanical sealing methods with thermal fusion bonding. By heating and fusing the bonding surfaces of the base plate, electrode terminal, and gasket, the patent creates a seamless bond that prevents gas and electrolyte leakage without requiring complex mechanical sealing structures.
Solution Approach 2:
The patent changes the bonding state from cold mechanical assembly to hot thermal fusion. The thermal fusion process melts and fuses the bonding surfaces together, creating a sealed bond that prevents leakage. The chromate surface treatment and PP-MAH layer parameters are optimized to ensure proper bonding and sealing during the thermal fusion process.
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 achieves a significant reduction in the thickness of the top plate assembly while ensuring strong bonding and insulation, thereby improving energy density and space efficiency, and effectively preventing gas and electrolyte leakage.
Implementation Method 1
the electrode terminal, the insulating gasket, and the base plate are bonded to each other through thermal fusion
Implementation Method 2
utilizing laser welding and insulating tape for enhanced sealing
Data Source
AI summary
A button-type secondary battery has a diameter greater than a height thereof. The button-type secondary battery includes an electrode assembly; a can body in which the electrode assembly is accommodated; a base plate configured to cover an opening of an upper end of the can body and bonded to the can body, the base plate having a through-hole therein; an electrode terminal of which at least a portion is disposed into the through-hole to cover the through-hole; and an insulating gasket configured to insulate the electrode terminal from the base plate. The electrode terminal, the insulating gasket, and the base plate are bonded to each other through thermal fusion.