pH-Responsive Binder for Battery Slurry Viscosity Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional binders for non-aqueous secondary batteries face issues with excessive viscosity elevation in slurry compositions, affecting their application and storage stability, and require improvement in binding capacity and preservation stability.
Innovation Solution
A binder with a particulate polymer that has controlled degrees of swelling at specific pH levels, incorporating acid group-containing monomers, aliphatic conjugated diene, and aromatic vinyl monomers, which maintains stability and binding capacity while suppressing viscosity elevation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a conventional binder is used to achieve binding capacity, then the binder can bind components in battery members, but the viscosity of the slurry composition increases excessively
Solution Approach 1:
The patent changes the chemical composition parameters of the binder by incorporating specific ratios of carboxylic acid group-containing polymer (0.1-10 mass%) and hydroxyl group-containing polymer (0.1-10 mass%) into the aqueous dispersion. This parameter optimization allows the binder to maintain strong binding capacity while controlling the viscosity of the slurry composition to acceptable levels for coating operations.
2Strength
If a conventional binder is used to achieve binding capacity, then the binder can bind battery members, but preservation stability deteriorates due to aggregation during transport or storage
Solution Approach 1:
The patent introduces water-soluble polymers with specific functional groups (carboxylic acid groups and hydroxyl groups) as intermediary substances that mediate between the particulate polymer particles and the aqueous dispersion medium. These intermediary polymers prevent aggregation of particles during storage and transport while maintaining effective binding capacity, thereby improving preservation stability.
3Strength
If the binder is made more effective for binding, then binding capacity improves, but the slurry composition becomes harder to apply onto substrate
Solution Approach 1:
The patent optimizes the viscosity parameters of the slurry composition by carefully controlling the concentrations of binder components (carboxylic acid group-containing polymer at 0.1-10 mass% and hydroxyl group-containing polymer at 0.1-10 mass%). This parameter adjustment ensures the slurry has appropriate flow characteristics for coating operations while maintaining sufficient binding capacity for effective adhesion to the substrate.
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 binder achieves excellent preservation stability, binding capacity, and suppresses viscosity elevation, enhancing the applicability and performance of non-aqueous secondary battery functional layers, particularly in high-temperature cycle characteristics.
Implementation Method 1
the particulate polymer has a degree of swelling in an aqueous medium at pH 5 of less than a factor of 2, and the particulate polymer has a degree of swelling in an aqueous medium at pH 8 of at least a factor of 2 and no greater than a factor of 7
Data Source
AI summary
Provided is a binder for a non-aqueous secondary battery that has excellent preservation stability and binding capacity, and that can suppress viscosity elevation of a slurry composition. The binder for a non-aqueous secondary battery contains a particulate polymer and water. The particulate polymer has a degree of swelling in an aqueous medium at pH 5 of less than a factor of 2 and has a degree of swelling in an aqueous medium at pH 8 of at least a factor of 2 and no greater than a factor of 7.