Solid-State Battery Cathode With Plasticizer-Solvated Lithium Salt
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing all-solid-state batteries face challenges in improving ionic conductivity and high-rate capability due to the difficulty in incorporating lithium salts into electrodes or electrolytes, as lithium salts do not dissolve in non-polar or low-polar solvents used in their manufacturing.
Innovation Solution
Incorporation of a plasticizer that is solid at room temperature and liquid at 60 °C or higher, along with a lithium salt, into the positive electrode of all-solid-state batteries, allowing the lithium salt to be solvated within the plasticizer, thereby enhancing ionic conductivity and high-rate capability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If lithium salts are added to electrodes or electrolytes to improve ionic conductivity and high-rate capability, then the battery performance is improved, but it is difficult to implement in all-solid-state batteries because lithium salts do not dissolve in non-polar or low-polar solvents used in manufacturing
Solution Approach 1:
The patent changes the physical state parameter of the plasticizer from solid to liquid by heating to 60°C or higher, enabling lithium salt dissolution. This parameter change (temperature-induced phase transition) resolves the contradiction by making the non-polar plasticizer capable of solvating lithium salts when in liquid state, thereby improving ionic conductivity while maintaining compatibility with the manufacturing process
Solution Approach 2:
The patent introduces a plasticizer as an intermediary substance between the lithium salt and the solid electrolyte. The plasticizer acts as a mediator that enables lithium salt incorporation into the electrode structure without directly reacting with the solid electrolyte, thus improving ionic conductivity while avoiding harmful interactions
2Productivity
If lithium salts are incorporated into the electrode to enhance high-rate capability, then the rate capability is improved, but the lithium salt may react with the solid electrolyte causing performance degradation
Solution Approach 1:
The plasticizer serves as a protective intermediary layer between the lithium salt and the solid electrolyte. By dissolving the lithium salt within the plasticizer matrix, the patent prevents direct contact and potential harmful reactions between the lithium salt and solid electrolyte, thus maintaining battery performance stability while enhancing high-rate capability
Solution Approach 2:
The patent converts the potential harmful effect of lithium salt-solid electrolyte interactions into a beneficial configuration where the plasticizer encapsulates the lithium salt. This arrangement prevents direct harmful reactions while still allowing ionic conductivity enhancement, effectively transforming a potential problem into a solution
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 solution improves ionic conductivity and high-rate capability of all-solid-state batteries by ensuring the lithium salt is uniformly distributed and does not react with the solid electrolyte, maintaining battery performance and energy density.
Implementation Method 1
a plasticizer that is solid at room temperature and liquid at 60 °C or higher
Implementation Method 2
The lithium salt may be solvated and present inside the plasticizer
Data Source
Figure 1
Figure 2
AI summary
The present invention relates to a positive electrode for an all-solid-state battery, and the positive electrode for an all-solid-state battery comprises a positive electrode layer including a positive electrode active material, a sulfide-based solid electrolyte, a positive electrolyte layer including a plasticizer and a lithium salt that is a solid at room temperature and liquid at 60 °C or higher, and a current collector supporting the positive electrode layer.