Lithium Anode Hybrid Coating for Stable Ion Transport
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium anodes in lithium ion batteries face challenges due to their reactivity with water and carbon dioxide, leading to the formation of lithium carbonate, which is brittle and reduces lithium transport.
Innovation Solution
A method of forming a lithium ion battery anode involves exposing a lithium layer to carbon dioxide gas to form a thin lithium carbonate layer, followed by depositing a fluoropolymer layer on top to create a hybrid coating that protects the lithium and facilitates lithium ion transport.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a lithium anode is used to achieve high theoretical specific capacity, then battery energy density is improved, but the lithium reacts with moisture and carbon dioxide to form brittle lithium carbonate that fractures and blocks lithium transport
Solution Approach 1:
The patent applies composite materials by creating a hybrid coating layer that combines fluoropolymer and lithium carbonate components. This composite structure provides both protection from environmental moisture and carbon dioxide, and maintains lithium ion transport pathways through the coating, resolving the contradiction between high capacity utilization and reliable lithium transport.
Solution Approach 2:
The patent uses a thin film coating approach where a fluoropolymer-based protective layer is deposited on the lithium anode surface. This thin film acts as a flexible barrier that protects the reactive lithium from environmental degradation while maintaining ion conductivity, preventing the formation of thick brittle lithium carbonate layers that would block transport.
2Object-affected harmful factors
If lithium carbonate forms a passivation layer on lithium, then protection from environment is improved, but the brittle lithium carbonate fractures as lithium bends, further exposing lithium to environment
Solution Approach 1:
The patent changes the physical and chemical parameters of the protective coating by using fluoropolymer materials with specific mechanical properties that are more flexible and adherent than conventional lithium carbonate layers. This parameter change allows the coating to maintain integrity during lithium bending while still providing environmental protection.
Solution Approach 2:
The fluoropolymer coating acts as an intermediary layer between the lithium anode and the environment. Instead of relying on brittle lithium carbonate to provide protection, this intermediary fluoropolymer layer provides both environmental barrier function and mechanical flexibility, preventing coating fracture during lithium deformation.
3Object-affected harmful factors
If lithium is stored in low humidity environments to prevent reaction with moisture, then reactivity is reduced, but handling and manufacturing complexity increases
Solution Approach 1:
The patent applies preliminary action by depositing the fluoropolymer protective coating on the lithium anode before battery assembly and manufacturing processes. This pre-applied protective layer enables the lithium to be handled in normal humidity environments during manufacturing, eliminating the need for complex low-humidity storage and handling infrastructure.
Solution Approach 2:
The fluoropolymer coating creates an inert protective environment around the reactive lithium metal, similar to how inert gas atmospheres are used. This chemical barrier allows the lithium to be manufactured and assembled in normal atmospheric conditions rather than requiring specialized low-humidity or inert atmosphere facilities.
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 hybrid coating enhances the stability and performance of the lithium anode by protecting it from moisture and preventing defluorination reactions, while also accommodating volume changes during charge and discharge cycles, thus improving the overall efficiency and lifespan of the battery.
Implementation Method 1
exposing a first surface of a lithium layer to carbon dioxide gas and forming a lithium carbonate layer on the first surface of the lithium layer
Implementation Method 2
depositing a fluoropolymer layer on a second surface of the lithium carbonate layer
Data Source
AI summary
A method of forming a lithium ion battery, a lithium ion battery anode, and a lithium ion battery for a vehicle. The method includes exposing a first surface of a lithium layer to carbon dioxide gas and forming a lithium carbonate layer on the first surface of the lithium layer. The method further includes depositing a fluoropolymer layer on a second surface of the lithium carbonate layer to provide a lithium anode. The battery includes one or more battery cells including the anode for the lithium ion battery. The anode includes a lithium layer including a first surface, and a hybrid coating layer disposed on the first surface, wherein the hybrid coating layer includes a plurality of lithium fluoride domains and a plurality of lithium carbonate domains within a carbonaceous matrix.