Solid Electrolyte Membrane Mixing for Lower Interface Resistance

Solution Overview

Problem

All-solid-state batteries face increased resistance at the interfaces of the positive and negative electrodes due to high hardness of the solid electrolyte membrane, which hinders efficient lithium ion migration and reduces battery performance.

Innovation Solution

A solid electrolyte membrane comprising a first solid electrolyte particle with a higher Young's modulus and a second solid electrolyte particle with a lower Young's modulus, mixed in specific weight ratios, to enhance interfacial bonding forces and minimize resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the hardness of the solid electrolyte membrane is increased, then the mechanical strength is improved, but the resistance to lithium ion migration at the interfaces increases

Engineering Contradiction:

Improvemechanical strengthVSAvoidinterface resistance

Core Design Contradiction:

StrengthVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by creating a core-shell structure where the solid electrolyte membrane has different properties at different locations: a hard core region for mechanical strength and a soft shell region for reduced interface resistance. This allows the membrane to simultaneously provide structural integrity and facilitate lithium ion migration at the interfaces with electrodes.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent uses composite materials by combining hard and soft regions within the solid electrolyte membrane. The core-shell structure integrates materials with different mechanical properties, where the core provides strength and the shell provides interfacial compatibility, resolving the contradiction between hardness and interface resistance.

Inventive Principle:

Principle #40Composite materials

2Stability of the object's composition

If the Young's modulus of the solid electrolyte particle is increased, then the structural stability is improved, but the interfacial bonding force with electrodes deteriorates

Engineering Contradiction:

Improvestructural stabilityVSAvoidinterfacial bonding force

Core Design Contradiction:

Stability of the object's compositionVSStrength

Solution Approach 1:

The patent applies local quality by creating a core-shell structure where the solid electrolyte membrane has different properties at different locations: a hard core region for mechanical strength and a soft shell region for reduced interface resistance. This allows the membrane to simultaneously provide structural integrity and facilitate lithium ion migration at the interfaces with electrodes.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent uses composite materials by combining hard and soft regions within the solid electrolyte membrane. The core-shell structure integrates materials with different mechanical properties, where the core provides strength and the shell provides interfacial compatibility, resolving the contradiction between hardness and interface resistance.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS20260018660A1Solid electrolyte membrane and all-solid-state battery comprising same

Publication Date: 2026.01.15 LG ENERGY SOLUTION LTD

AI summary

A solid electrolyte membrane for an all-solid-state battery, includes a first solid electrolyte particle and a second solid electrolyte particle, wherein the Young's modulus of the first solid electrolyte particle is higher than the Young's modulus of the second solid electrolyte particle, wherein the first solid electrolyte particle and the second solid electrolyte particle have an average particle size (D50) of 1 μm to 5 μm, wherein the first solid electrolyte particles and the second solid electrolyte particles are mixed in a weight ratio of less than 7:3 to 2:8, and an all-solid-state battery comprising the same.