Lithium Battery Electrolyte Additive for Stable SEI and Low Gas Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium secondary batteries face challenges with the stability and performance due to the high reactivity of aqueous electrolytes and the thermal instability of lithium salts, leading to issues such as gas generation, swelling, and reduced cycle lifetime characteristics.
Innovation Solution
An electrolyte additive comprising a compound with a sulfone group and an alkoxyamide group is introduced, which captures PF5− ions to suppress hydrolysis reactions, forms a stable SEI film on the anode, and reduces gas generation, thereby enhancing the battery's thermal stability and cycle life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If aqueous electrolytes are used in lithium secondary batteries, then ionic conductivity is improved, but reactivity with lithium increases leading to stability deterioration
Solution Approach 1:
The patent introduces an organic electrolyte as an intermediary medium between the lithium electrodes and the environment. This organic electrolyte mediates the ionic conduction while maintaining chemical stability, preventing direct harmful reactions between aqueous electrolytes and lithium electrodes. The organic solvent acts as a buffer that enables ion transport without the high reactivity characteristic of aqueous systems.
2Reliability
If lithium salts are used to provide lithium ions, then ionic conductivity is improved, but thermal stability deteriorates due to decomposition
Solution Approach 1:
The patent modifies the chemical structure of lithium salts by introducing fluorinated alkyl groups or aromatic substituents. These structural parameter changes raise the decomposition temperature of the lithium salt, preventing thermal decomposition and gas generation. The modified lithium salts maintain ionic conductivity while achieving the required thermal stability for safe battery operation.
3Duration of action of moving object
If conventional electrolytes are used, then manufacturing simplicity is maintained, but cycle lifetime characteristics deteriorate due to side reactions
Solution Approach 1:
The patent extracts and eliminates the problematic components from conventional electrolytes that cause side reactions. By removing traditional carbonate solvents and replacing them with stable organic solvents, and by selecting lithium salts with enhanced stability, the patent eliminates the sources of side reactions while maintaining the essential electrolyte functions of ionic conduction and electrode interface 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 additive improves the lithium secondary battery's high-temperature stability, cycle lifetime characteristics, and resistance, preventing overdischarging and maintaining battery performance by forming a rigid and chemically stable SEI film.
Implementation Method 1
captures PF5− ions to suppress hydrolysis reactions
Implementation Method 2
forms a stable SEI film on the anode
Data Source
AI summary
An electrolyte additive for a lithium secondary battery, an electrolyte, and a lithium secondary battery, the additive including a compound represented by Formula 1 below: