Battery Packaging Material Yield Strength and Moldability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional film-shaped battery packaging materials face challenges in maintaining moldability due to the ease of pinhole and crack generation during molding, which can lead to electrolyte leakage and short-circuits, and existing techniques have not adequately addressed the properties of the metal layer for improved moldability.
Innovation Solution
A battery packaging material with a laminate structure comprising a base material layer, an adhesive layer, and a metal layer, where the metal layer is an aluminum foil with a 0.2% yield strength of 55 to 140 N/mm2 and the thickness ratio of the base material layer to the metal layer is between 1:1 to 1:3, enhancing the material's ability to withstand molding without pinholes or cracks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If a film-shaped laminate is used as battery packaging material, then weight reduction and thickness reduction are achieved, but pinholes and cracks are easily generated during molding
Solution Approach 1:
The patent changes the mechanical parameter of the metal layer by selecting aluminum foil with a specific yield strength range (55-140 N/mm² at 0.2% elongation). This parameter optimization allows the film-shaped laminate to maintain both weight reduction benefits and improved moldability, reducing pinhole and crack generation during deep drawing processes
Solution Approach 2:
The patent uses a composite structure consisting of a base material layer and a metal layer (aluminum foil) with specific properties. This composite material approach combines the lightweight advantage of film materials with the enhanced formability provided by the optimized metal layer, resolving the contradiction between weight reduction and moldability
2Ease of manufacture
If aluminum foil with low yield strength is used as metal layer, then processability is improved and deformation is easier, but the material is more prone to creasing and poor moldability
Solution Approach 1:
The patent optimizes the yield strength parameter of the aluminum foil to a specific range (55-140 N/mm² at 0.2% elongation). This parameter change balances the material's deformability and resistance to creasing, achieving both ease of manufacture and excellent moldability in film-shaped battery packaging
Data Source
AI summary
A technique relates to a packaging material for a battery, including a laminate of film form including at least a base material layer, an adhesive layer, a metal layer, and a sealant layer, laminated in that order, the packaging material being resistant to cracks or pinholes occurring during molding, and having exceptional moldability. The packaging material for a battery is characterized by including a laminate of at least a base material layer, an adhesive layer, a metal layer, and a sealant layer, laminated in that order, the metal layer being aluminum foil having 0.2% proof stress of 55-140 N/mm2 when subjected to tensile testing in a parallel direction to the rolling direction, and the ratio of thickness of the base material layer and the metal layer (base material layer thickness:metal layer thickness) being within the range 1:1 to 1:3.