Binder Composition for Secondary Battery Electrode
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional binder compositions for secondary battery electrodes do not adequately enhance binding capacity and electrical characteristics such as rate and cycle performance.
Innovation Solution
A binder composition combining a first particulate polymer with a degree of swelling in electrolysis solution of at least 400 mass % and a glass transition temperature of −60° C. to −15° C., and a second particulate polymer with a degree of swelling of greater than 100 mass % and a glass transition temperature of −10° C. to 30° C., is used to improve binding capacity and electrical characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional binder compositions are used, then manufacturing simplicity is maintained, but binding capacity and electrical characteristics are insufficient
Solution Approach 1:
The patent uses a composite binder system comprising two distinct particulate polymer types with different glass transition temperatures and swelling properties. This composite approach enables simultaneous achievement of high binding capacity and excellent electrical characteristics that cannot be obtained with single polymer binders, resolving the contradiction between performance improvement and composition complexity.
Solution Approach 2:
The patent optimizes specific parameters of the particulate polymers including glass transition temperature ranges (first polymer: -60°C to -15°C, second polymer: -10°C to 30°C) and swelling degree in electrolyte solution (first polymer: 400-900%, second polymer: 100-200%). By precisely controlling these parameters, the binder composition achieves superior binding capacity and electrical characteristics while maintaining manageable formulation complexity.
2Strength
If binder compositions with higher binding capacity are used, then electrode adhesion is improved, but electrical characteristics such as rate and cycle performance deteriorate
Solution Approach 1:
The patent employs two particulate polymers with specifically controlled glass transition temperatures. The first polymer (Tg: -60°C to -15°C) provides excellent binding capacity and adhesion, while the second polymer (Tg: -10°C to 30°C) maintains electrical conductivity and ion transport properties. This dual-polymer system with optimized Tg parameters resolves the contradiction by decoupling the binding function from the electrical function.
Solution Approach 2:
The binder composition exhibits local quality differentiation where the first particulate polymer primarily contributes to binding capacity and adhesion properties, while the second particulate polymer primarily maintains electrical characteristics and ion conductivity. This functional differentiation within the composite binder system allows simultaneous optimization of both binding capacity and electrical performance without mutual interference.
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 composition achieves excellent binding capacity, rate characteristics, and cycle characteristics for secondary batteries by optimizing the swelling properties and glass transition temperatures of the polymers.
Implementation Method 1
a first particulate polymer having a degree of swelling in electrolysis solution of at least 400 mass % and a glass transition temperature of −60° C. to −15° C.
Implementation Method 2
a second particulate polymer having a degree of swelling in electrolysis solution of greater than 100 mass % and a glass transition temperature of −10° C. to 30° C.
Data Source
AI summary
Provided is a binder composition for a secondary battery electrode that has excellent binding capacity and can cause a secondary battery to display excellent rate characteristics and cycle characteristics. The binder composition for a secondary battery electrode contains: a first particulate polymer having a degree of swelling in electrolysis solution of at least 400 mass % and no greater than 900 mass % and a glass transition temperature of at least −60° C. and no higher than −15° C.; a second particulate polymer having a degree of swelling in electrolysis solution of greater than 100 mass % and no greater than 200 mass % and a glass transition temperature of at least −10° C. and no higher than 30° C.; and water.