All-Solid-State Battery Binder Composition for Stable Slurry Coating

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing binder compositions for all-solid-state secondary batteries fail to achieve optimal viscosity and fluidity for slurry application, leading to poor battery characteristics and processability during production.

Innovation Solution

A binder composition comprising a polymer, an unsaturated acid metal salt monomer with a divalent metal, and a solvent, with a water content below 1,000 ppm, is used to create a slurry composition with improved dispersion stability and pressability, resulting in better battery characteristics and production processability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a binder composition is added to achieve good battery characteristics, then battery performance is improved, but the viscosity and fluidity of the slurry composition become unsuitable for application

Engineering Contradiction:
Improvebattery characteristicsVSAvoidslurry application processability
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The invention changes the chemical composition parameters of the binder by specifying a polymer with carboxyl groups (0.1-10 mass%) and a metal salt of polybasic acid (0.01-5 mass%), which modifies the slurry's rheological properties to achieve both good battery characteristics and suitable viscosity for application

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention uses a composite binder system combining polymer with carboxyl groups and metal salt of polybasic acid, creating a composite material that simultaneously provides adhesion for battery performance and controls viscosity for manufacturability

Inventive Principle:
Principle #40Composite materials

2Productivity

If the solid content concentration of the slurry composition is increased to improve productivity, then production efficiency is improved, but the dispersion stability deteriorates

Engineering Contradiction:
Improveproduction efficiencyVSAvoiddispersion stability
Core Design Contradiction:
ProductivityVSStability of the object's composition

Solution Approach 1:

The invention optimizes the concentration parameters of binder components (polymer 0.1-10 mass%, metal salt 0.01-5 mass%) to achieve a balance where high solid content (60-80 mass%) slurry maintains adequate dispersion stability while improving productivity

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3726634B1Binder composition for all-solid-state secondary battery, slurry composition for all-solid-state secondary battery, functional layer for all-solid-state secondary battery, and all-solid-state secondary battery
Publication Date: 2025.09.17 ZEON CORP

AI summary

Provided are a binder composition for an all-solid-state secondary battery with which it is possible to obtain an all-solid-state secondary battery that has good battery characteristics and for which processability during all-solid-state secondary battery production is excellent, a slurry composition for an all-solid-state secondary battery that contains this binder composition for an all-solid-state secondary battery, a functional layer for an all-solid-state secondary battery that is formed from this slurry composition for an all-solid-state secondary battery, and an all-solid-state secondary battery that includes this functional layer for an all-solid-state secondary battery. The binder composition for an all-solid-state secondary battery contains a polymer, an unsaturated acid metal salt monomer, and a solvent. The unsaturated acid metal salt monomer includes a divalent metal.