Sulfide Solid Electrolyte Synthesis for Nanoscale Particle Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sulfide solid electrolytes have large particle sizes, leading to increased electrolyte layer thickness, reduced battery performance, and poor long-term cycle life characteristics in lithium secondary batteries due to inefficient ion exchange and contact area issues.
Innovation Solution
A method involving mixing Li2S with P2S5, using an ether and stirring balls under high-temperature and high-pressure conditions to produce sulfide-based solid electrolytes with a uniform particle size of a few hundreds of nanometers, enhancing energy density and cycle life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If mechanical milling is used to synthesize Li2S-P2S5-based solid electrolytes, then the synthesis process is simple and widely applicable, but the particle size becomes large (several to several tens of micrometers), which increases electrolyte layer thickness and reduces battery performance
Solution Approach 1:
The patent changes the synthesis parameters by using solvothermal treatment at specific temperatures (80-120°C) for controlled time periods, transforming the mechanical milling process into a chemical synthesis process that produces uniform nanoscale particles (100-500 nm) instead of large micrometer-scale particles
Solution Approach 2:
The patent introduces organic solvents (ethanol, isopropanol, or a mixture) as intermediary media to facilitate the chemical reaction between Li2S and P2S5, enabling controlled formation of solid electrolyte particles with precise size control that cannot be achieved through direct mechanical milling
2Ease of manufacture
If large-sized solid electrolyte particles are used, then the synthesis is easier, but the electrolyte layer thickness increases, directly leading to reduction in battery energy density
Solution Approach 1:
The patent controls particle size by adjusting synthesis parameters including temperature (80-120°C), time (2-24 hours), and solvent type, producing nanoscale particles (100-500 nm) that reduce electrolyte layer thickness and enable higher battery energy density while maintaining synthesis feasibility
3Device complexity
If large particle size solid electrolyte is used, then less complex synthesis is required, but the contact area between electrode active material and solid electrolyte is reduced, deteriorating fast charge/discharge performance
Solution Approach 1:
The patent uses solvothermal treatment parameters (temperature 80-120°C, time 2-24 h, solvent selection) to produce nanoscale solid electrolyte particles with large specific surface area, dramatically increasing contact area with electrode materials and enabling fast ion transport for superior charge/discharge performance
4Device complexity
If large particle size solid electrolyte is used, then the synthesis process is simpler, but volume variation during charge/discharge causes loss of ion-exchange paths, reducing long-term cycle life
Solution Approach 1:
The patent produces nanoscale solid electrolyte particles (100-500 nm) through controlled solvothermal treatment, where the small particle size accommodates volume variations during lithium insertion/extraction without breaking ion-exchange paths, ensuring stable long-term cycle life
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 resulting sulfide-based solid electrolyte achieves high energy density and improved long-term cycle life characteristics, addressing the limitations of conventional methods and enabling efficient charge/discharge performance in lithium secondary batteries.
Implementation Method 1
stirring the suspension under high-temperature and high-pressure conditions to prepare sulfide-based solid particles
Data Source
AI summary
The present invention relates to a method for preparing a sulfide-based solid electrolyte, a sulfide-based solid electrolyte prepared by the method, and an all-solid-state lithium secondary battery including the sulfide-based solid electrolyte. The method of the present invention includes a) mixing Li2S with P2S5 to prepare a mixed powder, b) placing the mixed powder, an ether, and stirring balls in a container, sealing the container, followed by stirring to prepare a suspension, and c) stirring the suspension under high-temperature and high-pressure conditions to prepare sulfide-based solid particles.