Cobalt-Free Cathode Material to Suppress LiMnO2 and LiMn2O4
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ternary battery materials, such as NCM, face challenges in endurance mileage, safety performance, and rising costs due to cobalt and nickel prices, with cobalt posing environmental hazards, and exhibit capacity loss and poor cycle performance due to lamellar LiMnO2 and spinel LiMn2O4 formation during charging and discharging.
Innovation Solution
A cobalt-free and nickel-free positive electrode material is developed using a divalent manganese compound to inhibit the formation of lamellar LiMnO2 and spinel LiMn2O4, promoting the generation of Li2MnO3, which improves cycle performance, and a preparation method involving a mixture of lithium, manganese, and sodium salts with specific molar ratios, followed by heating and coating with AlPO4 and TiO2 to enhance ion diffusion and structural stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If cobalt and nickel are used in NCM ternary materials to achieve high energy density, then the energy density is improved, but the cost increases and environmental pollution worsens
Solution Approach 1:
The patent removes cobalt and nickel elements from the NCM ternary material composition, extracting the harmful and expensive elements while retaining the manganese-based cathode structure. This is achieved by using a manganese-rich layered oxide (Li1-xMn1-yO2) as the base material and controlling the synthesis conditions to prevent formation of harmful spinel phases, thereby eliminating the need for cobalt and nickel while maintaining acceptable energy density
Solution Approach 2:
The patent replaces expensive cobalt and nickel with cheaper manganese-based materials. The manganese-rich layered oxide structure provides a cost-effective alternative that, while having shorter initial cycle life compared to NCM, achieves acceptable longevity through surface modification and controlled synthesis that prevents rapid degradation
2Use of energy by moving object
If NCM materials are used to achieve high energy density, then the energy density is improved, but the safety performance and endurance mileage worsen
Solution Approach 1:
The patent changes the compositional parameters by using a manganese-rich formulation (Li1-xMn1-yO2 with specific x and y values) instead of traditional NCM compositions. The synthesis conditions are also parameter-controlled (temperature, atmosphere, time) to produce a stable layered structure that resists degradation during cycling, thereby improving safety and endurance while maintaining energy density
3Use of energy by moving object
If conventional ternary materials are used for battery preparation, then the energy density is achieved, but the capacity loss increases and cycle performance deteriorates due to lamellar LiMnO2 and spinel LiMn2O4 formation
Solution Approach 1:
The patent applies preliminary anti-action by controlling the synthesis conditions to prevent the formation of harmful lamellar LiMnO2 and spinel LiMn2O4 phases before they can degrade the battery performance. This is achieved through controlled heating rates, oxygen atmosphere management, and composition optimization that stabilizes the layered structure and prevents Jahn-Teller distortion and disproportionation reactions that would otherwise occur during charging-discharging cycles
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 results in a battery with improved cycle performance, reduced pollution, lower costs, and enhanced safety by preventing capacity loss and promoting the formation of lamellar Li2MnO3, leading to higher endurance mileage and better safety performance.
Implementation Method 1
the divalent manganese compound is added in the preparation process to inhibit the generation of lamellar LiMnO2 and spinel LiMn2O4, promote the generation of Li2MnO3
Implementation Method 2
heating the mixture to obtain the cobalt-free and nickel-free matrix material
Data Source
AI summary
The present disclosure provides a cobalt-free and nickel-free positive electrode material and a preparation method therefor, and a battery. The preparation method includes: preparing a cobalt-free and nickel-free matrix material, and mixing the cobalt-free and nickel-free matrix material, a lithium source, and a divalent manganese compound for reaction to obtain the cobalt-free and nickel-free positive electrode material. By adding the divalent manganese compound, the generation of lamellar LiMnO2 and spinel LiMn2O4 is inhibited, the generation of lamellar Li2MnO3 is promoted, and the cycle performance of the material is improved.