Electrode Binder Composition for Stable Viscosity and Peel Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional binder compositions for electrochemical devices face challenges in maintaining viscosity stability while achieving strong adhesion of the electrode mixed material layer to the current collector, leading to suboptimal peel strength.
Innovation Solution
A binder composition comprising a nitrile polymer, N-methyl-2-pyrrolidone, and a halogenated hydrocarbon, with the halogenated hydrocarbon content within a specific range (2-400 mass ppm), which enhances viscosity stability and peel strength by improving adherence to the current collector.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a nitrile polymer is used as a binder composition, then adhesion to current collector is improved, but viscosity stability deteriorates
Solution Approach 1:
The patent changes the chemical composition parameters of the binder by introducing a halogenated hydrocarbon component at specific concentrations (0.1-10 wt% relative to nitrile polymer). This parameter modification allows the system to achieve both strong adhesion to current collector and improved viscosity stability, resolving the contradiction between these two properties.
Solution Approach 2:
The patent creates a composite binder system by combining nitrile polymer with halogenated hydrocarbon. This composite approach allows the nitrile polymer to provide adhesion to current collector while the halogenated hydrocarbon component contributes to viscosity stability, enabling both functions to coexist without compromising either property.
2Stability of the object's composition
If halogenated hydrocarbon content is increased, then viscosity stability is improved, but adhesion to current collector deteriorates
Solution Approach 1:
The patent identifies and applies an optimal concentration range for halogenated hydrocarbon (0.1-10 wt% relative to nitrile polymer). Within this parameter range, the system achieves both improved viscosity stability and maintained adhesion to current collector. This precise parameter control resolves the contradiction by finding the optimal balance point.
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 proposed binder composition achieves excellent viscosity stability and peel strength, reducing electrode resistance and improving cycle characteristics of electrochemical devices.
Implementation Method 1
A binder composition comprising: a nitrile polymer; N-methyl-2-pyrrolidone; and a halogenated hydrocarbon, wherein content of the halogenated hydrocarbon is not less than 2 mass ppm and not more than 400 mass ppm relative to content of the nitrile polymer
Data Source
AI summary
Provided is a binder composition for an electrochemical device that has excellent viscosity stability and is capable of forming an electrode having excellent peel strength. The binder composition contains a polymer including a nitrile group-containing monomer unit, N-methyl-2-pyrrolidone, and a halogenated hydrocarbon. The content of the halogenated hydrocarbon is not less than 2 mass ppm and not more than 400 mass ppm relative to the content of the polymer.