Composite Electrolyte Electrode Structure for Safe Li-Ion Conductivity

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithium secondary batteries using liquid organic electrolytes are prone to leakage, explosion, and ignition due to rapid environmental changes, while solid electrolytes like polymer and ceramic electrolytes face issues of low ionic conductivity and non-uniform interfacial contact.

Innovation Solution

An electrode structure for lithium secondary batteries is developed, featuring a composite electrolyte layer composed of an oxide-based electrolyte and a polymer electrolyte, where the oxide-based electrolyte is sintered to form a sintered body, with a volume ratio of 55:45 to 90:10, and a porosity of 10-50 vol%, enhancing interfacial bonding and electrochemical stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If a liquid organic electrolyte is used, then discharge capacity and energy density are improved, but safety and reliability deteriorate due to leakage, explosion, and ignition risks

Engineering Contradiction:

Improvedischarge capacityVSAvoidsafety

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The patent employs a composite electrolyte system combining polymer electrolyte and oxide-based electrolyte in specific volume ratios. The polymer electrolyte provides safety and structural stability, while the oxide-based electrolyte enhances ionic conductivity. This composite approach resolves the contradiction by integrating the advantages of both materials to achieve both high discharge capacity and safety.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent optimizes the volume ratio parameters of polymer electrolyte and oxide-based electrolyte (specifically 60:40 to 70:30) to achieve the desired balance between ionic conductivity and safety. By carefully controlling these compositional parameters, the electrolyte system attains both high discharge capacity and improved safety characteristics.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If a polymer electrolyte is used, then safety is improved, but ionic conductivity deteriorates

Engineering Contradiction:

ImprovesafetyVSAvoidionic conductivity

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The patent combines polymer electrolyte with oxide-based electrolyte to create a composite system where the oxide-based electrolyte compensates for the low ionic conductivity of the polymer electrolyte. The polymer matrix provides safety and mechanical stability, while the oxide-based electrolyte dispersed within it enhances ion transport, achieving both safety and adequate ionic conductivity.

Inventive Principle:

Principle #40Composite materials

3Quantity of substance

If a ceramic electrolyte is used, then ionic conductivity is improved, but interfacial contact uniformity deteriorates

Engineering Contradiction:

Improveionic conductivityVSAvoidinterfacial contact uniformity

Core Design Contradiction:

Quantity of substanceVSManufacturing precision

Solution Approach 1:

The patent integrates oxide-based electrolyte particles within a polymer electrolyte matrix. The polymer component provides flexibility and conformability, enabling uniform interfacial contact with electrodes, while the oxide-based electrolyte particles maintain high ionic conductivity. This composite structure resolves the contradiction between ionic conductivity and interfacial contact uniformity.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The polymer electrolyte matrix acts as a flexible medium that can conform to electrode surfaces, ensuring uniform interfacial contact. The flexibility of the polymer component allows the electrolyte layer to adapt to surface irregularities, achieving consistent contact while the embedded oxide-based electrolyte maintains high ionic conductivity.

Inventive Principle:

Principle #30Flexible shells and thin films

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 composite electrolyte layer improves lithium ion conductivity, energy density, and lifespan of the battery by preventing impurity generation and crack formation, ensuring uniform interfacial contact and high electrochemical stability.

Implementation Method 1

the oxide-based electrolyte includes a sintered body

Methodology Applied

Scientific EffectSintering: Sintering

Implementation Method 2

a volume of the oxide-based electrolyte contained in the composite electrolyte layer is greater than a volume of the polymer electrolyte contained in the composite electrolyte layer

Methodology Applied

Scientific EffectIonic conduction: Conduction (electrical)

Data Source

PatentEP4708431A2Electrode structure for lithium secondary battery and manufacturing method therefor

Publication Date: 2026.03.11 SK ON CO LTD

Figure 1~4
Figure 5a~5b
Figure 6a~6b

AI summary

An electrode structure for a lithium secondary battery according to exemplary embodiments may comprise: a negative electrode; and a composite electrolyte layer formed on the negative electrode and including an oxide-based electrolyte and a polymer electrolyte. The oxide-based electrolyte may include a sintered body, and the volume of the oxide-based electrolyte included in the composite electrolyte layer may be more than that of the polymer electrolyte included in the composite electrolyte layer. Accordingly, a lithium secondary battery having improved capacity characteristics and lifespan characteristics can be provided.