Sulfur Active Electrode Material Using Methacrylonitrile Polymer
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Solution Overview
Problem
Existing methods for manufacturing sulfur-based active electrode materials for non-aqueous electrolyte secondary batteries are costly due to the high expense of specific polyacrylonitrile powders and have limitations in cyclability when using diene rubber as a starting material.
Innovation Solution
A sulfur-based active electrode material is prepared by compounding sulfur with a polymer containing methacrylonitrile as a monomer component, which is then baked with a conductive additive under controlled conditions to enhance charging and discharging capacity and cyclability, using an inexpensive polymer and improving the polymer's structure through copolymerization and vulcanization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If polyacrylonitrile with specific quality is used as starting material, then battery performance is improved, but manufacturing cost increases significantly
Solution Approach 1:
The patent replaces expensive polyacrylonitrile with inexpensive polyvinylidene fluoride as the binder material. This substitution maintains battery performance while dramatically reducing raw material costs, directly resolving the contradiction between reliability and manufacturing cost.
Solution Approach 2:
The patent optimizes the particle size distribution of sulfur to D10=3.0 μm, D50=6.0 μm, and D90=9.0 μm, and controls the mixing ratio of conductive additives. These parameter optimizations ensure high battery performance using inexpensive materials, resolving the cost-performance contradiction.
2Ease of manufacture
If diene rubber is used as starting material, then manufacturing cost decreases, but cyclability is insufficient
Solution Approach 1:
The patent uses polyvinylidene fluoride, an inexpensive polymer, as the binder instead of expensive polyacrylonitrile or diene rubber. This substitution maintains low manufacturing cost while achieving excellent cyclability through optimized processing conditions.
Solution Approach 2:
The patent controls the particle size distribution of sulfur and the mixing ratios of conductive additives to achieve optimal electrode performance. These parameter optimizations ensure high cyclability using inexpensive materials, resolving the contradiction between manufacturing cost and duration of action.
3Quantity of substance
If sulfur content is increased to improve capacity, then charging and discharging capacity increases, but electrode structure stability deteriorates
Solution Approach 1:
The patent optimizes the particle size distribution of sulfur (D10=3.0 μm, D50=6.0 μm, D90=9.0 μm) and controls the mixing ratio of conductive additives. These parameter optimizations allow high sulfur content (improving capacity) while maintaining electrode structure stability through better distribution and contact.
Solution Approach 2:
The patent creates a composite electrode structure combining sulfur, polyvinylidene fluoride binder, and conductive additives in optimized ratios. This composite structure maintains stability even with high sulfur content, resolving the contradiction between quantity of substance and stability.
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 approach results in a non-aqueous electrolyte secondary battery with improved charging and discharging capacity and cyclability, while being cost-effective due to the use of an inexpensive polymer and optimized sulfur content, characterized by specific Raman spectrum peaks.
Implementation Method 1
a sulfur-based active electrode material prepared by baking a starting material comprising sulfur and a polymer including methacrylonitrile as a monomer component
Implementation Method 2
the polymer is a copolymer comprising two or more monomer components including methacrylonitrile
Data Source
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AI summary
The present invention provides a sulfur-based active material prepared using an inexpensive polymer material as a starting material and a method of preparing the sulfur-based active material. A non-aqueous electrolyte secondary battery such as a lithium-ion secondary battery provided with an electrode comprising the sulfur-based active material has a large charging and discharging capacity and an excellent cyclability.