Delithiated Lithium Transition-Metal Nitride Anodes for High-Current Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lithium-ion battery negative electrode materials, such as graphite and lithium titanate, face limitations in capacity and high-current performance, leading to potential safety issues and unsatisfactory in-cell performance.
Innovation Solution
A method for delithiating lithium and transition metal nitrides, specifically by mixing an oxidizing agent with the nitrides, followed by recovery of the delithiated material, which can then be used as a negative electrode active material in lithium-ion batteries.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If lithium titanate is used as negative electrode material to avoid lithium plating, then safety is improved, but capacity is reduced
Solution Approach 1:
The invention changes the working potential parameter of the negative electrode material from 1.5V (lithium titanate) to approximately 0.1V vs Li/Li+, enabling the use of high-capacity materials without lithium plating. This is achieved through a novel electrode material composition containing lithium-deficient spinel structure with specific cation distribution, allowing operation at lower potentials while maintaining safety.
2Quantity of substance
If graphite is used as negative electrode material to increase capacity, then capacity is improved, but lithium plating occurs at high charging currents
Solution Approach 1:
The invention changes the working potential parameter to approximately 0.1V vs Li/Li+, which is optimal for preventing lithium plating while maintaining high capacity. This potential is lower than both graphite and lithium titanate, enabling safe high-current operation with high capacity.
3Quantity of substance
If lithium transition metal nitrides are used as electrode materials, then capacity is improved, but in-cell performance is unsatisfactory
Solution Approach 1:
The invention optimizes the working potential parameter to approximately 0.1V vs Li/Li+, which significantly improves in-cell performance. The lithium-deficient spinel structure with controlled cation distribution enables both high capacity and satisfactory in-cell performance by preventing lithium plating during high-current charging.
Solution Approach 2:
The invention uses a composite electrode material with lithium-deficient spinel structure containing specific transition metals (Mn, Ni, Co, Cu, Zn, Fe) in controlled ratios. This composite structure combines high capacity with improved in-cell performance by operating at optimal potential.
4Power
If high charging current is applied to increase power, then power is improved, but lithium plating occurs reducing battery capacity
Solution Approach 1:
The invention optimizes the working potential parameter to approximately 0.1V vs Li/Li+, which prevents lithium plating even at high charging currents. This enables high power delivery without capacity loss from plating.
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 delithiated material avoids the need for an initial discharge step, enhances capacity and high-current performance, and improves safety by preventing lithium plating, thus offering a more efficient and safer battery performance.
Implementation Method 1
mixing at least one oxidising agent with said lithium and transition metal nitride
Data Source
AI summary
A method for delithiating a lithium and transition metal nitride. The method involves mixing an oxidising agent with the lithium and transition metal nitride and recovering the material obtained. The transition metal may be Mn, Fe, Co, Ni, Cu, or a mixture thereof. The material obtained by the method may be used as a negative electrode material for a lithium-ion battery.