Solid State Electrolyte for Lithium Battery Safety

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Rechargeable lithium metal and lithium-ion batteries face challenges such as dendrite formation, thermal runaway, and flammability due to organic solvents, leading to safety concerns and limited commercialization, with existing solid-state electrolytes having low lithium ion conductivities and high costs.

Innovation Solution

A solid-state electrolyte composition comprising a lithium ion-conducting polymer matrix and inorganic species, such as Li2CO3, dispersed or chemically bonded within the polymer, providing high lithium ion conductivity and safety without flammability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If organic liquid solvents are used in the electrolyte, then lithium ion conductivity is improved, but flammability and thermal runaway risk increase

Engineering Contradiction:

Improvelithium ion conductivityVSAvoidflammability

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the physical state of the electrolyte from liquid to solid by using a polymer matrix, thereby eliminating flammability while maintaining lithium ion conductivity through careful selection of polymer chemistry and additives

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite solid electrolyte consisting of a polymer matrix combined with lithium salts and conductive additives, achieving both safety (non-flammable) and performance (high conductivity) simultaneously

Inventive Principle:

Principle #40Composite materials

2Object-affected harmful factors

If solid state electrolyte is used to prevent dendrites and thermal runaway, then safety is improved, but lithium ion conductivity decreases

Engineering Contradiction:

ImprovesafetyVSAvoidlithium ion conductivity

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent optimizes the polymer matrix composition and structure to enhance lithium ion mobility, achieving conductivity levels comparable to liquid electrolytes while maintaining the safety advantages of solid state

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces lithium salts and conductive additives as intermediaries within the polymer matrix to facilitate lithium ion transport, bridging the gap between safety and conductivity requirements

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If complex anode or electrolyte structures are designed to prevent dendrites, then dendrite prevention is improved, but device complexity increases

Engineering Contradiction:

Improvedendrite preventionVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent modifies the electrolyte properties locally at the electrode interface to prevent dendrite formation, rather than requiring complex overall structural changes throughout the battery system

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The solid electrolyte composition itself provides dendrite prevention through its inherent physical and chemical properties, eliminating the need for additional complex protective structures or mechanisms

Inventive Principle:

Principle #25Self-service

4Reliability

If advanced solid state electrolyte materials are used to achieve high conductivity and safety, then performance is improved, but manufacturing cost increases

Engineering Contradiction:

Improvelithium ion conductivityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent employs cost-effective polymer materials and common lithium salts that can be procured and processed economically, making the solid electrolyte commercially viable despite performance requirements

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent optimizes the composition ratios and processing parameters to achieve high conductivity with minimal amounts of expensive additives, reducing overall material costs while maintaining performance

Inventive Principle:

Principle #35Parameter changes

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 solution achieves high energy density, long cycle life, and safety in lithium batteries by preventing dendrite formation and thermal runaway, with lithium ion conductivity exceeding 10^-3 S/cm, suitable for lithium-sulfur and lithium-ion cells.

Implementation Method 1

a lithium ion-conducting inorganic species that is dispersed in or chemically bonded by the polymer matrix or binder

Methodology Applied

Scientific EffectIon conduction: Conduction (electrical)

Data Source

PatentUS11374254B2Solid state electrolyte for lithium secondary battery

Publication Date: 2022.06.28 HONEYCOMB BATTERY CO

AI summary

Provided is a solid state electrolyte composition for a rechargeable lithium battery. The electrolyte composition comprises a lithium ion-conducting polymer matrix or binder and lithium ion-conducting inorganic species that is dispersed in or chemically bonded by the polymer matrix or binder, wherein the lithium ion-conducting inorganic species is selected from Li2CO3, Li2O, Li2C2O4, LiOH, LiX, ROCO2Li, HCOLi, ROLi, (ROCO2Li)2, (CH2OCO2Li)2, Li2S, LixSOy, or a combination thereof, wherein X=F, Cl, I, or Br, R=a hydrocarbon group, 0<x≤1, 1≤y≤4; and wherein the polymer matrix or binder is in an amount from 1% to 99% by volume of the electrolyte composition. Also provided are a process for producing this solid state electrolyte and a lithium secondary battery containing such a solid state electrolyte.