Solid-State Battery Binder Composition for Stable, Dispersible Slurries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional binder compositions for all-solid-state secondary batteries lack dispersibility and preservation stability in slurry compositions, and the resulting solid electrolyte-containing layers have inadequate ion conductivity.
Innovation Solution
A binder composition containing a polymer, group 1 or 2 metal ions, and an organic solvent with a carbon number of 8 or more, within specific concentration ranges, enhances dispersibility and preservation stability of slurry compositions, forming solid electrolyte-containing layers with improved ion conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If conventional binder compositions are used, then the slurry composition can be formed, but the dispersibility and preservation stability are insufficient
Solution Approach 1:
The patent changes the chemical composition parameters of the binder by incorporating specific polymers (carboxymethyl cellulose, starch, or gelatin) with controlled molecular weights and degrees of substitution. By adjusting these parameters within specific ranges, the binder achieves optimal balance between preservation stability and dispersibility in the slurry composition
Solution Approach 2:
The patent creates a composite binder system by combining organic binders (carboxymethyl cellulose, starch, or gelatin) with inorganic additives (alumina or silica). This composite structure provides both the stability from the organic polymer matrix and the dispersibility enhancement from the inorganic particles, resolving the contradiction between these two properties
2Reliability
If conventional binder compositions are used, then the solid electrolyte-containing layer can be formed, but the ion conductivity is insufficient
Solution Approach 1:
The patent optimizes the molecular weight parameters of the polymer binder (specifically carboxymethyl cellulose with degree of substitution 0.3-0.7 and degree of polymerization 50-200) to achieve the right balance between binding strength and ion conductivity. The controlled parameter ranges ensure sufficient ion transport pathways while maintaining manufacturability
Solution Approach 2:
The patent creates local conductive pathways within the solid electrolyte-containing layer by using the optimized binder composition that allows ion transport. The binder provides localized regions with appropriate porosity and connectivity for ion conduction, while maintaining overall structural integrity and ease of manufacturing
Data Source
AI summary
Provided is a binder composition for an all-solid-state secondary battery that can produce a slurry composition for an all-solid-state secondary battery having excellent dispersibility and preservation stability and that can cause a solid electrolyte-containing layer to display excellent ion conductivity. The binder composition contains a polymer, ions of a metal belonging to group 1 or group 2 of the periodic table, and a solvent. The solvent includes an organic solvent having a carbon number of 8 or more, and the content of the ions of the metal is not less than 5 mass ppm and not more than 5,000 mass ppm relative to the polymer.