Halogen-Doped Glass Solid Electrolyte for High Ionic Conductivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lithium-ion batteries face challenges with low filling rates and ionic conductivity in solid electrolytes, particularly in Li3PS4 glasses, which have low ionic conductivity below 1 mS/cm.
Innovation Solution
A glass solid electrolyte composed of lithium, phosphorus, sulfur, and halogen, with specific molar ratios and incorporating lithium bromide and iodide, is developed to enhance filling rate and ionic conductivity, achieved through mechanical softening and vitrification of the mixture.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If Li3PS4 glass is used as solid electrolyte, then filling rate is improved, but ionic conductivity deteriorates (below 1 mS/cm)
Solution Approach 1:
The patent changes the chemical composition parameters of the glass solid electrolyte by incorporating halogen elements (bromine and/or iodine) in specific molar ratios (X/P = 0.05 to 2.0). This compositional parameter change transforms the Li3PS4 glass into a halogen-doped glass system that achieves both high filling rate (≥90% relative density) and high ionic conductivity (≥1 mS/cm), resolving the contradiction between packing efficiency and ion transport performance
Solution Approach 2:
The patent creates a composite glass solid electrolyte system combining Li3PS4 base glass with halogen compounds (LiBr, LiI, PBr3, PI3, etc.). This composite material approach integrates the high filling rate advantage of glassy structures with the high ionic conductivity contribution from halogen-doped regions, achieving simultaneous optimization of both filling rate and ionic conductivity
2Quantity of substance
If mechanical softening is applied to increase filling rate, then consolidation characteristic is improved, but structural stability may deteriorate
Solution Approach 1:
The patent utilizes the glass transition phenomenon to achieve mechanical softening at processing temperatures, enabling high filling rate consolidation. The halogen-doped glass composition is designed to maintain structural stability after cooling and solidification, creating a stable amorphous phase that preserves both the high density achieved during pressing and the ionic conductivity required for battery operation
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 new glass solid electrolyte achieves a filling rate equal to or higher than conventional electrolytes and exhibits ionic conductivity of 1 mS/cm or greater, suitable for lithium-ion batteries.
Implementation Method 1
the glass solid electrolyte has an ionic conductivity of 1 mS/cm or greater
Implementation Method 2
the glass solid electrolyte shows peaks derived from lithium bromide in powder X-ray diffraction using CuKα ray
Implementation Method 3
a relative density of a green compact pressurized at 400 MPa is 90% or more
Data Source
AI summary
A glass solid electrolyte comprising lithium, phosphorus, sulfur and halogen comprising at least bromine as constituent elements, wherein a molar ratio (Li/P) of the lithium (Li) to the phosphorus (P) is 2.0 to 5.3, a molar ratio (S/P) of the sulfur (S) to the phosphorus (P) is 2.0 to 4.5, and a molar ratio (X/P) of the halogen (X) to the phosphorus (P) is 0.7 to 2.3, and the glass solid electrolyte shows peaks derived from lithium bromide in powder X-ray diffraction using CuKα ray.