Halogen-Substituted Solid Electrolyte for Battery Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solid electrolyte materials, such as sulfide solid electrolytes, pose safety risks due to the potential generation of hydrogen sulfide when exposed to the atmosphere, and they often struggle with maintaining high lithium-ion conductivity across varying temperatures, especially in all-solid-state batteries.
Innovation Solution
A novel solid electrolyte material composed of Li, M (where M is Ta or Nb), Al, O, and X (where X is F, Cl, or Br) is developed, which achieves high lithium-ion conductivity and is substantially free of sulfur, ensuring safety and stability across a wide temperature range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sulfide solid electrolyte materials are used, then lithium-ion conductivity can be achieved, but hydrogen sulfide generation occurs when exposed to the atmosphere causing safety risks
Solution Approach 1:
The patent changes the chemical composition parameters of the solid electrolyte by replacing sulfur with halogen elements (F, Cl, Br) in the formula LiaMebYcZ6, where Z is specifically F, Cl, or Br. This compositional parameter change eliminates the sulfur component that generates hydrogen sulfide, thereby resolving the safety issue while maintaining ionic conductivity through optimized stoichiometric ratios.
Solution Approach 2:
The patent creates a composite solid electrolyte material combining multiple elements (Li, M, Al, O, and halogen X) in a specific composite structure. This composite approach replaces the simple sulfide structure with a more complex multi-element compound that achieves both high ionic conductivity and chemical stability, preventing hydrogen sulfide generation while maintaining battery performance.
2Temperature
If conventional solid electrolyte materials are used, then battery operation is possible, but lithium-ion conductivity decreases at varying temperatures especially outside standard ranges
Solution Approach 1:
The patent optimizes the compositional parameters (a, b, c ratios of different elements) in the solid electrolyte formula to achieve stable ionic conductivity across a wide temperature range. By adjusting the stoichiometric ratios and selecting specific halogen elements, the material's thermal stability and ionic conductivity are enhanced, allowing reliable battery operation from -30°C to 80°C.
3Reliability
If sulfur-containing solid electrolyte materials are used, then high ionic conductivity can be achieved, but safety is compromised due to hydrogen sulfide generation
Solution Approach 1:
The patent converts the harmful sulfur component into a beneficial halogen-based structure. By replacing sulfur with halogen elements (F, Cl, Br), the material eliminates the harmful hydrogen sulfide generation while maintaining or enhancing ionic conductivity. The halogen elements provide both structural stability and ionic transport pathways, turning a safety hazard into a safe, high-performance electrolyte material.
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 novel solid electrolyte material exhibits high lithium-ion conductivity (1 × 10-3 mS/cm or more) and maintains excellent charge and discharge characteristics in batteries, even at varying temperatures from -30°C to 80°C, while being free of sulfur, thus preventing hydrogen sulfide generation and enhancing safety.
Implementation Method 1
The solid electrolyte material according to the first embodiment can have, for example, practical lithium-ion conductivity, and can have, for example, high lithium-ion conductivity. Here, high lithium-ion conductivity is, for example, 1 × 10-3 mS/cm or more.
Data Source
AI summary
A solid electrolyte material of the present disclosure includes: Li; M; Al; O; and X, wherein the M is at least one selected from the group consisting of Ta and Nb, and the X is at least one selected from the group consisting of F, Cl, and Br.