Solid-State Lithium-Ion Conductor Composition for Safe High Conductivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current solid-state lithium batteries face challenges with ionic conductivity and safety concerns due to the toxicity and reactivity of sulfide electrolytes, while oxide electrolytes have limited application due to low conductivity and incompatibility with high-voltage cathode materials.
Innovation Solution
Development of solid-state ion conductors with specific compounds like Li(3+2y1)B(P1-y1A1y1O4), Li5+4(6-a2)y2B(S1-y2A2y2O4), and Li(2+m3+3y3(6-b))M3m3A3(2-m3)(S(1-y3)Xby3O4) that provide high ionic conductivity and stability, using dopants to create distorted lithium environments for improved conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sulfide solid-state electrolytes are used, then lithium conductivity is improved, but toxicity and safety concerns increase due to reaction with air or water to evolve hydrogen sulfide
Solution Approach 1:
The patent employs composite materials by combining sulfur and phosphorus elements in specific ratios within the solid-state electrolyte structure. This composite approach allows the material to achieve high lithium conductivity comparable to sulfides while eliminating the toxic hydrogen sulfide evolution through the phosphorus component's stability in air and water.
Solution Approach 2:
The patent changes the chemical composition parameters by introducing phosphorus into the electrolyte structure and controlling the S/P ratio. This parameter modification transforms the material properties to achieve both high conductivity and safety, resolving the contradiction between performance and toxicity.
2Object-affected harmful factors
If oxide solid-state electrolytes are used, then toxicity is reduced and stability in air is improved, but lithium conductivity and compatibility with high-voltage cathode materials deteriorate
Solution Approach 1:
The patent creates a composite electrolyte structure combining characteristics of both oxides and sulfides through the specific Li-S-P compound formulation. This composite approach inherits the safety and stability of oxides while achieving the high conductivity typically associated with sulfides, thus resolving the contradiction between safety and performance.
Solution Approach 2:
The developed solid-state electrolyte achieves multi-functionality by simultaneously providing high lithium conductivity, air stability, and compatibility with both lithium metal and high-voltage cathode materials. This universal performance allows a single material to replace multiple specialized electrolytes.
3Ease of manufacture
If conventional solid-state electrolytes are used, then manufacturing simplicity is maintained, but ionic conductivity and compatibility with various battery components are limited
Solution Approach 1:
The patent modifies the chemical composition parameters of the solid-state electrolyte by controlling the ratios of Li, S, and P elements. This parameter optimization enables the material to achieve broad electrochemical stability windows, allowing compatibility with diverse battery components including lithium metal anodes and high-voltage cathodes while maintaining manufacturability.
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 proposed solid-state ion conductors achieve high ionic conductivity and stability, enabling efficient lithium ion transport and compatibility with various battery components, thus addressing the limitations of existing electrolytes.
Implementation Method 1
Solid-state lithium batteries can provide improved specific energy and energy density... Available sulfides can provide greater lithium conductivity than oxides
Data Source
AI summary
A solid-state ion conductor including a compound of Formula 1:Li(3+2y1)B(P1-y1A1y1O4)2 Formula 1wherein, in Formula 1, A1 is an element of Groups 4, 14, or a combination thereof, and has an oxidation state of +4, and 0<y1<1.