Anode Protective Layer Prevents Aluminum Film Piercing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Secondary batteries face issues with package bag leakage due to sharp corners and burrs on the anode current collector piercing the aluminum plastic film, leading to chemical corrosion and potential leakage, as the thickness of components is reduced to increase energy density.
Innovation Solution
An electrode assembly with a protective layer made of insulating materials like polyolefin, polyurethane, or silicone, which covers the edges and corners of the anode electrode to prevent piercing and corrosion, reducing the risk of leakage by absorbing piercing forces and wrapping burrs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the thickness of the separator, aluminum plastic film, and current collector is reduced to increase energy density, then the energy density of the secondary battery is improved, but the current collector becomes prone to forming sharp corners that can pierce the aluminum plastic film
Solution Approach 1:
A protective layer is pre-applied to the current collector before assembly, covering the edges and corners that would otherwise form sharp points. This preliminary protective measure prevents the current collector from piercing the aluminum plastic film during battery formation and operation, while still allowing the use of thin components for high energy density.
Solution Approach 2:
The protective layer acts as a cushioning layer between the current collector and the aluminum plastic film. This cushioning effect absorbs and distributes the stress at the edges and corners of the current collector, preventing concentrated stress points that would cause piercing, while maintaining the thin-profile design for high energy density.
2Quantity of substance
If the thickness of the separator, aluminum plastic film, and current collector is reduced to increase energy density, then the energy density of the secondary battery is improved, but the chemical corrosion risk increases when burrs contact the aluminum layer
Solution Approach 1:
The protective layer serves as an intermediary barrier between the current collector (with its burrs) and the aluminum plastic film. This intermediate layer prevents direct contact between the copper burrs and the aluminum film, thereby eliminating the chemical reaction that would cause corrosion, while allowing the use of thinner components for high energy density.
Solution Approach 2:
The protective layer is applied in advance to the current collector surface, creating a protective barrier before the battery is assembled. This preliminary protection prevents burrs from contacting and corroding the aluminum plastic film during subsequent handling and operation, enabling the use of thin components without increased corrosion risk.
3Quantity of substance
If the thickness of the separator, aluminum plastic film, and current collector is reduced to increase energy density, then the energy density of the secondary battery is improved, but leakage phenomenon occurs in the aluminum plastic film
Solution Approach 1:
The protective layer is applied to the current collector before assembly, preemptively covering the edges and corners that would otherwise create stress concentration points. This preliminary protection prevents the formation of leakage paths in the aluminum plastic film, allowing the use of thin components for high energy density without compromising leakage resistance.
Solution Approach 2:
The protective layer provides beforehand cushioning at the critical edge and corner regions of the current collector. This cushioning effect distributes mechanical stress and prevents the formation of sharp corners that would pierce or weaken the aluminum plastic film, thereby preventing leakage while maintaining thin-component design for high energy density.
Data Source
AI summary
A battery includes a first conductive layer having a folded portion, a first edge, and a second edge opposite to the first edge in a first direction of the battery; a first conductive plate located on the first conductive layer; and a first layer comprising an insulating material covering at least one portion of the folded portion, and being distant from the first conductive layer. The first layer partially covers the first edge of the first conductive layer.