Lithium Metal Battery Electrolyte for Low-Temperature Operation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium metal batteries face challenges with reduced ionic conductivity at low temperatures and inadequate suppression of lithium dendrite growth, leading to short circuits and reduced cycle life.
Innovation Solution
An electrolyte comprising a composite of a non-carbonate-based lithium ion-conductive compound, a polymerization product of a crosslinkable polymer, and a lithium salt, specifically using glycol ether and ion-conductive inorganic particles to enhance mechanical strength and ion conductivity, thereby preventing lithium dendrite growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional electrolytes are used in lithium metal batteries, then the batteries can operate at normal temperatures, but ionic conductivity decreases significantly at low temperatures
Solution Approach 1:
The patent uses a composite electrolyte consisting of polyethylene oxide (PEO) polymer matrix combined with lithium trifluoromethanesulfonate (LiCF3SO3) salt and glyme (diglyme or triglyme) additives. This composite structure allows the electrolyte to maintain flexibility and ionic conductivity at low temperatures while preserving the solid electrolyte's safety advantages. The glyme components specifically enhance low-temperature performance by reducing the glass transition temperature of the PEO matrix.
2Reliability
If conventional electrolytes are used, then the battery structure is simple, but lithium dendrite growth is not effectively suppressed leading to short circuits
Solution Approach 1:
The patent modifies the electrolyte's physical and chemical parameters by selecting specific molecular weights for PEO (200,000-400,000 g/mol) and precise molar ratios of components (Li salt to PEO at 0.3-0.6 mol/mol, glyme to PEO at 0.5-2.0 mol/mol). These parameter optimizations create an electrolyte with enhanced lithium ion solvation capability and controlled viscosity, which suppresses dendrite growth while maintaining a relatively simple two-component system.
3Reliability
If the electrolyte is made more conductive, then ionic conductivity improves, but mechanical strength may be compromised
Solution Approach 1:
The patent creates local structural variations within the electrolyte by incorporating glyme molecules that preferentially solvate lithium ions in specific regions, creating conductive pathways with high ionic mobility. The PEO chains maintain the overall mechanical matrix structure while the glyme-Li complexes form localized conductive zones. This spatial differentiation allows simultaneous optimization of conductivity and mechanical properties.
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 electrolyte enables improved ionic conductivity and mechanical strength, allowing lithium metal batteries to operate effectively at low temperatures and extending cycle life by suppressing lithium dendrite formation.
Implementation Method 1
a polymerization product of a crosslinkable polymer
Implementation Method 2
a lithium ion-conductive compound which is a non-carbonate-based substance having resistance to reduction of lithium metal
Data Source
AI summary
Provided are an electrolyte for a lithium metal battery and a lithium metal battery including the electrolyte, wherein the electrolyte includes a composite including a lithium ion-conductive compound which is a non-carbonate-based substance having resistance to reduction of lithium metal, a polymerization product of a crosslinkable polymer, and a lithium salt, wherein the lithium ion-conductive compound is glycol ether.