Plastic Substrate Current Collector with Adhesion and Oxidation Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lithium ion battery positive electrode current collectors face challenges in achieving high energy density, light weight, and cost reduction due to limitations in thinning aluminum foils, which results in reduced mechanical strength and increased susceptibility to oxidation and peeling of the aluminum coating layer.
Innovation Solution
A multilayered positive electrode current collector structure comprising a plastic thin film with a bonding force enhancement layer and an anti-oxidization layer, where the plastic thin film is coated with a metallic or nonmetallic bonding force enhancement layer and an anti-oxidization layer in sequence, enhancing the adhesion and protection of the aluminum metal coating layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If the aluminum foil is thinned to reduce weight and increase energy density, then the weight and thickness are reduced, but the mechanical strength is reduced and processability deteriorates
Solution Approach 1:
The patent uses a composite structure consisting of a plastic thin film substrate combined with an aluminum metal coating layer. This composite material approach allows the aluminum layer to be much thinner (1-10 μm vs. traditional 8 μm minimum) while the plastic substrate provides the necessary mechanical strength and processability, resolving the contradiction between weight reduction and strength maintenance
Solution Approach 2:
The patent employs a plastic thin film (such as PET, PI, or OPP) as the substrate, which inherently possesses good flexibility and mechanical properties. This thin film base allows the aluminum coating to be applied at very thin thicknesses while maintaining overall structural integrity and processability, enabling weight reduction without sacrificing mechanical strength
2Reliability
If the aluminum coating layer thickness is increased to achieve satisfactory conductivity, then the conductivity is improved, but the aluminum coating layer becomes more prone to falling off from the plastic
Solution Approach 1:
The patent optimizes the aluminum coating thickness parameter to a specific range (1-10 μm) that is much thinner than traditional aluminum foils but sufficient for achieving satisfactory conductivity. This parameter optimization, combined with the plastic substrate and surface treatment, maintains conductivity while reducing the tendency for coating delamination
Solution Approach 2:
The plastic thin film substrate acts as an intermediary between the aluminum coating layer and the external environment. It provides a stable base that prevents direct contact between the thin aluminum layer and corrosive electrolyte, thereby improving adhesion stability and preventing coating fall-off while maintaining conductivity
3Object-affected harmful factors
If conventional anti-oxidation methods are used on aluminum coated on plastic, then oxidation protection is provided, but the aluminum coating layer easily falls off
Solution Approach 1:
The patent applies a thin aluminum oxide layer (formed through anodization or other oxidation methods) on the aluminum coating surface. This oxide layer serves as a protective copy or barrier that prevents further oxidation of the underlying aluminum while the specific treatment process maintains strong adhesion between the aluminum and plastic substrate, avoiding coating fall-off
4Weight of moving object
If the plastic thin film thickness is reduced to achieve weight reduction, then the weight and thickness are reduced, but the manufacturing precision and process control become more difficult
Solution Approach 1:
The patent employs a plastic thin film (such as PET, PI, or OPP) as the substrate, which inherently possesses good flexibility and mechanical properties. This thin film base allows the aluminum coating to be applied at very thin thicknesses while maintaining overall structural integrity and processability, enabling weight reduction without sacrificing mechanical strength
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 50% weight reduction and 30% thickness reduction, improving energy density, preventing peeling of the aluminum coating, and protecting against oxidation, thereby enhancing the mechanical strength and manufacturing capability of the battery.
Implementation Method 1
the upper and lower surfaces of the plastic thin film are coated with a bonding force enhancement layer
Implementation Method 2
an anti-oxidization layer... protecting against oxidation
Implementation Method 3
double-side roundtrip electron beam evaporation coating machine... bombarding evaporation material Al2O3 with accelerated electrons by using an electron gun, and adjusting unwinding speed, rewinding speed and evaporation rate
Data Source
AI summary
The present invention provides a positive electrode current collector, and a preparation method and use thereof. The positive electrode current collector is of a multilayered structure and comprises a plastic thin film, wherein the upper and lower surfaces of the plastic thin film are coated with a bonding force enhancement layer, an aluminum metal coating layer and an anti-oxidization layer in sequence. The preparation method comprises the steps of coating the bonding force enhancement layer, the aluminum metal coating layer and the anti-oxidization layer in sequence through an evaporation film-coating process. Use of the positive electrode current collector in a lithium ion battery is further provided. By virtue of the positive electrode current collector according to the present invention, light weight and improved energy density of the battery is realized, and the aluminum coating layer is not easily peeled off, and insusceptible to oxidization.