Composite Electrode Layering for Uniform Lithium Supplementation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lithium supplementation methods for lithium-ion batteries result in non-uniform distribution of lithium elements, leading to poor uniformity, slow infiltration rates, and potential side reactions, which affect battery performance and cycle life.
Innovation Solution
A composite electrode structure with alternately stacked active substance and lithium supplement layers, where porosity and thickness of the lithium supplement layers increase gradually away from the current collector, facilitating faster lithium diffusion and reducing side reactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If lithium supplement agent is mixed with active material of electrode, then lithium supplementation is achieved, but side reactions occur and uniformity deteriorates
Solution Approach 1:
The electrode is divided into multiple thin layers alternating between active substance layers and lithium supplement layers. This segmentation prevents direct contact and mixing between lithium supplement agent and active material, eliminating side reactions while ensuring uniform lithium distribution throughout the electrode structure.
Solution Approach 2:
The alternating layer structure acts as an intermediary arrangement that separates the lithium supplement agent from the active material. The layered configuration allows lithium ions to diffuse uniformly without direct chemical interaction between the supplement agent and active substance, preventing unwanted side reactions.
2Quantity of substance
If conventional lithium supplementation methods are used, then lithium is added to electrode, but infiltration rate is slow and uniformity is poor
Solution Approach 1:
The electrode is divided into multiple thin layers alternating between active substance layers and lithium supplement layers. This segmentation creates multiple interfaces for lithium ion diffusion, significantly increasing the infiltration rate and ensuring uniform distribution throughout the electrode structure.
Solution Approach 2:
The invention transitions from conventional mixing methods to a multi-dimensional layered structure. By stacking multiple thin layers alternately, the lithium supplement agent is distributed uniformly in three dimensions, creating numerous diffusion pathways that accelerate infiltration rate and improve uniformity.
3Ease of manufacture
If lithium supplement layers have uniform porosity, then manufacturing is simple, but lithium ion diffusion efficiency is reduced
Solution Approach 1:
The porosity of lithium supplement layers is designed to vary locally based on position. Layers closer to the current collector have different porosity characteristics than layers farther away, optimizing lithium ion diffusion efficiency at different depths while maintaining manufacturability through controlled deposition parameters.
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
This structure enhances lithium supplementation efficiency, improves uniformity, and increases energy density by accelerating lithium ion diffusion, reducing initial capacity loss, and enhancing cycle performance.
Implementation Method 1
the diffusion path of the lithium ions is shorter, and the diffusion rate of the lithium ions can be accelerated
Data Source
Figure 1~2
AI summary
A composite electrode, a manufacturing method thereof, and a lithium-ion battery are provided. The composite electrode includes a current collector; and a composite material layer disposed on at least one side surface of the current collector. The composite material layer comprises n-layer active substance layers and n-1-layer lithium supplement layers that are stacked at intervals, in which n is greater than or equal to 3 and n is an integer. A side of the composite material layer which is adjacent to the current collector is one of the n-layer active substance layers. Porosity of the n-1-layer lithium supplement layers gradually increases along a direction away from the current collector.