Ceramic-Polymer Composite Electrolyte for Lithium Batteries

Solution Overview

Problem

Ceramic and polymeric materials used in lithium batteries face challenges such as brittleness, delamination, low ionic conductivity, and lithium dendrite growth, which existing technologies have not adequately addressed, particularly in achieving a balance between ionic conductivity and mechanical stability.

Innovation Solution

A ceramic-polymer composite electrolyte is developed, incorporating ionically-conductive ceramic particles in a solid polymer matrix with chemical additives to reduce interface resistance, enhancing ionic conductivity and mechanical strength while preventing dendrite growth.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ceramic materials are used as electrolyte, then ionic conductivity is improved, but mechanical brittleness and delamination occur

Engineering Contradiction:

Improveionic conductivityVSAvoidmechanical strength

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent creates a composite electrolyte material by embedding ceramic particles (such as LLZO, LATP, or LISICON) into a polymer matrix (such as PEO or PVDF-HFP). This composite structure allows the material to inherit the high ionic conductivity of ceramics while gaining the flexibility and mechanical strength of polymers, thereby resolving the contradiction between ionic conductivity and mechanical strength.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent optimizes parameters including ceramic particle size (0.1-10 μm), ceramic content (30-70 wt%), and polymer molecular weight to achieve the best balance between ionic conductivity and mechanical properties. By carefully controlling these parameters, the composite electrolyte achieves high ion transport while maintaining mechanical integrity and flexibility.

Inventive Principle:

Principle #35Parameter changes

2Strength

If polymer materials are used as electrolyte, then mechanical flexibility is improved, but ionic conductivity decreases

Engineering Contradiction:

Improvemechanical flexibilityVSAvoidionic conductivity

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The patent creates a composite electrolyte material by embedding ceramic particles (such as LLZO, LATP, or LISICON) into a polymer matrix (such as PEO or PVDF-HFP). This composite structure allows the material to inherit the high ionic conductivity of ceramics while gaining the flexibility and mechanical strength of polymers, thereby resolving the contradiction between ionic conductivity and mechanical strength.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent optimizes parameters including ceramic particle size (0.1-10 μm), ceramic content (30-70 wt%), and polymer molecular weight to achieve the best balance between ionic conductivity and mechanical properties. By carefully controlling these parameters, the composite electrolyte achieves high ion transport while maintaining mechanical integrity and flexibility.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If ceramic particles are added to polymer matrix, then ionic conductivity is improved, but interface resistance increases

Engineering Contradiction:

Improveionic conductivityVSAvoidinterface resistance

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent introduces surface modification agents or coating layers on ceramic particles to act as intermediaries between the ceramic and polymer phases. This reduces interfacial resistance and improves ion transport across the ceramic-polymer interface, resolving the contradiction between enhanced ionic conductivity and reduced interface resistance.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent optimizes ceramic particle surface treatment and interface chemistry to minimize interfacial resistance. By controlling surface energy, wettability, and chemical compatibility at the ceramic-polymer interface, the composite achieves low interfacial resistance while maintaining high bulk ionic conductivity.

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 ceramic-polymer composite electrolyte achieves improved ionic conductivity and mechanical stability, effectively blocking dendrite growth and maintaining performance across battery cycles, with conductivity and transference number enhancements.

Implementation Method 1

The chemical additive is configured to reduce ionic resistance at interfaces between the ceramic particles and the ionically-conductive solid polymer

Methodology Applied

Scientific EffectInterfacial resistance reduction:

Implementation Method 2

ionically-conductive ceramic particles distributed in a matrix of ionically-conductive solid polymer

Methodology Applied

Scientific EffectIonic conduction: Conduction (electrical)

Implementation Method 3

preventing dendrite growth

Methodology Applied

Scientific EffectPhysical barrier effect:

Data Source

PatentEP3398223B1Ceramic-polymer composite electrolytes for lithium polymer batteries

Publication Date: 2021.06.30 SEEO INC

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AI summary

Composites of lithium-ion-conducting ceramic and polymeric materials make superior separators and electrolytes for use in lithium batteries. The ceramic material provides a high conductivity pathway for lithium-ions, enhancing the properties of the less conductive polymeric material. The polymeric material provides flexibility, binding, and space-filling properties, mitigating the tendency of rigid ceramic materials to break or delaminate. The interface between the polymer and ceramic can be made to have a low ionic resistance through the use of additives and coatings.