Lithium-Manganese Solid Solution Electrode Suppressing Gas Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium-manganese-type solid solution positive electrode materials for lithium batteries suffer from significant gas generation during the initial cycle, limiting their application in large-sized batteries.
Innovation Solution
A lithium-manganese-type solid solution positive electrode material with a monoclinic structure of C2/m in a hexagonal structure of space group R-3m, expressed by the composition formula xLi4/3Mn2/3O2+(1−x)LiMnαCoβNiγO2, where 0.2≦α≦0.6, 0≦β≦0.4, and 0.2≦γ≦0.6, and x is between 0.36 and 0.50, effectively suppresses gas generation by optimizing the molar ratio and incorporating substitution elements like Nb, V, Mg, Al, and Ti, with a c-axis length of 14.255 Å to 14.275 Å, and specific peak area ratios in XRD patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If lithium-manganese-type solid solution positive electrode material is used to achieve high energy density and reduced raw material cost, then energy density is improved and cost is reduced, but gas generation occurs during initial cycle
Solution Approach 1:
The patent applies parameter changes by precisely controlling the compositional parameters (x between 0.36-0.50, α between 0.2-0.6, β between 0-0.4, γ between 0.2-0.6) of the solid solution material xLi4/3Mn2/3O2·(1-x)LiMnαCoβNiγO2. This compositional optimization resolves the contradiction by achieving high energy density while suppressing gas generation through specific stoichiometric ratios.
Solution Approach 2:
The patent creates a composite solid solution material combining Li4/3Mn2/3O2 and LiMnαCoβNiγO2 in specific proportions. This composite approach allows the material to simultaneously achieve high energy density from the Li4/3Mn2/3O2 component and reduced gas generation through the stabilizing effect of the LiMnαCoβNiγO2 component with optimized transition metal composition.
2Quantity of substance
If solid solution positive electrode material is used to achieve high capacity, then capacity is improved, but gas generation occurs particularly in initial cycle
Solution Approach 1:
The patent resolves this contradiction by optimizing the compositional parameters of the solid solution, specifically setting x between 0.36-0.50 to balance capacity and gas suppression. The transition metal ratios (α, β, γ) are also optimized to maintain high capacity while reducing gas generation during initial cycling.
Solution Approach 2:
The patent applies local quality by differentiating the functional roles of different components in the solid solution. The Li4/3Mn2/3O2 component (with x=0.36-0.50) provides high capacity, while the LiMnαCoβNiγO2 component provides structural stability and gas suppression, creating localized functional zones within the composite material.
Data Source
AI summary
Provided is a lithium-manganese-type solid solution positive electrode material capable of effectively suppressing gas generation in an initial cycle. Proposed is a lithium-manganese-type solid solution positive electrode material that includes a monoclinic structure of C2/m in a hexagonal structure of a space group R-3m. The lithium-manganese-type solid solution positive electrode material contains a solid solution expressed by a composition formula: xLi4/3Mn2/3O2+(1−x)LiMnαCoβNiγO2 (in the formula, 0.2≦α≦0.6, 0≦β≦0.4, and 0.2≦γ≦0.6). In the composition formula, x is equal to or more than 0.36 and less than 0.50.