Solid Electrolyte Impregnation for Lithium-Ion Battery Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing method for producing electrode assemblies for lithium-ion batteries requires adjusting precursor solutions based on the porosity of active material molded bodies, which is time-consuming and labor-intensive, and repeated heat treatments can lead to thermal history effects and lithium desorption, affecting ion conduction properties.
Innovation Solution
A method involving dipping a molded body into a melt of solid electrolyte in one atmosphere and then cooling it in a lower atmosphere to impregnate and combine the solid electrolyte with the molded body, reducing thermal history and allowing for efficient ion conductivity, regardless of porosity, using a gas like CO2 to suppress lithium and carbon decomposition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If precursor solution is impregnated into porous molded body followed by heat treatment to form solid electrolyte, then solid electrolyte is formed in voids, but thermal history remains and lithium may be desorbed affecting ion conduction property
Solution Approach 1:
The patent changes the temperature parameter from high-temperature heat treatment to low-temperature melt impregnation. By dissolving the solid electrolyte in an organic solvent to create a precursor solution, the impregnation process occurs at low temperature, avoiding thermal history and lithium desorption while still enabling solid electrolyte formation in the voids
Solution Approach 2:
The patent utilizes phase transition of the organic solvent from liquid to gas. The solvent evaporates after impregnation, leaving behind the solid electrolyte in the voids. This phase transition allows the solid electrolyte to be deposited without requiring high-temperature heat treatment that would cause thermal history effects
2Manufacturing precision
If porosity of active material molded body is measured beforehand to adjust precursor solution amount, then appropriate impregnation is achieved, but time and labor are required
Solution Approach 1:
The patent employs capillary action, a self-service mechanism, where the precursor solution automatically penetrates into the voids of the molded body through capillary forces. This eliminates the need for precise porosity measurement and manual adjustment of solution amounts, as the system self-regulates the impregnation process
Solution Approach 2:
The patent utilizes capillary action, a hydraulic phenomenon, to enable the precursor solution to penetrate the porous structure. By controlling the viscosity and surface tension of the precursor solution, adequate impregnation is achieved without requiring precise knowledge of porosity, thus reducing measurement time and labor
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
This approach results in an electrode assembly with enhanced ion conductivity and reduced waste, maintaining high lithium ion conductivity and electric capacity while minimizing thermal degradation.
Implementation Method 1
the melt is impregnated into the voids inside the molded body by capillary phenomenon
Implementation Method 2
cooling the molded body impregnated with the melt by moving the molded body to a second atmosphere whose temperature is lower than that of the first atmosphere
Data Source
AI summary
A method for producing an electrode assembly which includes a first step of forming a molded body that contains an active material, a second step of dipping the molded body in a melt of a solid electrolyte in a first atmosphere, thereby impregnating the melt into voids inside the molded body; and a third step of cooling the molded body impregnated with the melt by moving the molded body to a second atmosphere whose temperature is lower than that of the first atmosphere, thereby combining the molded body with the solid electrolyte.