Conductive Composition for Electrodes Using Multi-Walled Carbon Nanotubes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lithium-ion battery electrodes face challenges with high production costs and limited dispersibility of carbon nanotubes (CNTs), leading to suboptimal conductivity and energy density, which are exacerbated by the need for additional costly conductive materials like carbon black.
Innovation Solution
A conductive composition for electrodes comprising carbon black and multi-walled carbon nanotubes with improved conductivity and dispersibility, characterized by specific powder resistivity, volume-converted median diameter, and D/G value, along with a binder and dispersant, enhances the binding properties and reduces pole plate resistance, resulting in higher energy density and output characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional CNTs are used as conductive materials, then high conductivity can be obtained with low conductive carbon material content, but the CNTs form complicatedly entangled secondary structures that reduce dispersibility and binding properties
Solution Approach 1:
The CNTs are segmented into smaller diameter units (0.5-5 nm) which prevents complicated entanglement and improves dispersibility in the electrode slurry, while maintaining the conductive network structure necessary for high conductivity
Solution Approach 2:
The outer diameter parameter of CNTs is changed from conventional larger dimensions to specifically 0.5-5 nm, which fundamentally alters their entanglement behavior and dispersibility characteristics while preserving their conductive functionality
2Ease of manufacture
If CNTs with improved dispersibility are used, then binding properties improve, but production cost increases due to additional costly conductive materials like carbon black
Solution Approach 1:
The invention replaces expensive, difficult-to-disperse CNTs with cheaper, easily dispersible small-diameter CNTs that achieve the same or better performance, eliminating the need for additional costly conductive materials like carbon black
Solution Approach 2:
The invention creates a composite conductive system using small-diameter CNTs combined with specific binder materials (PVDF, CMC, SBR) that synergistically improve both dispersibility and binding properties while controlling overall cost
3Reliability
If CNTs form complicatedly entangled secondary structures, then conductivity paths are established, but the binding property at the boundary surface between positive electrode material and aluminum current collector decreases
Solution Approach 1:
Segmenting CNTs into smaller diameters reduces entanglement complexity and creates a more uniform distribution that maintains conductive paths while improving contact and binding at the electrode-current collector interface
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 composition achieves improved economy, conductivity, and dispersibility, forming strong conductive paths that enhance binding properties and provide higher energy density, output characteristics, and cycle stability in non-aqueous batteries.
Implementation Method 1
a conductive composition for electrodes, as well as an electrode and a battery using the same... comprising: a conductive material containing carbon black and multi-walled carbon nanotubes... forming strong conductive paths that enhance binding properties and provide higher energy density
Implementation Method 2
improved conductivity and dispersibility... along with a binder and dispersant... dispersibility of the CNTs in the positive electrode is important
Implementation Method 3
a conductive composition for electrodes... comprising: a conductive material containing carbon black and multi-walled carbon nanotubes; an active material; a binder... enhances the binding properties
Data Source
AI summary
Provided is a conductive composition for electrodes, the conductive composition having excellent electrical conductivity and dispersibility. Also provided are: a positive electrode for non-aqueous batteries, the positive electrode using the conductive composition and having low electrode plate resistance and excellent binding properties; and a non-aqueous battery having high energy density, high output characteristics, and high cycle characteristics. The conductive composition for electrodes contains a conductive material, an active material, a binder, and a dispersant, wherein the conductive material contains carbon black and a multi-walled carbon nanotube having a powder resistivity of 0.035 Ω·cm or less as measured under a load of 9.8 MPa, and a median volumetric diameter D50 value, which is as a measure of dispersibility, in the range of 0.3-8 μm The positive electrode which is for non-aqueous batteries and has low electrode plate resistance and excellent binding properties; and the non-aqueous battery having high output characteristics and high cycle characteristics are obtained by using the conductive composition in which the content of the multi-walled carbon nanotube in the conductive material is 3-50 mass %.