Fluorinated Electrolyte for Low Internal Resistance Batteries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium secondary batteries face challenges in achieving low internal resistance and maintaining high-temperature storage performance, which are crucial for improved battery efficiency and reliability, especially in applications like automobiles.
Innovation Solution
A specific electrolyte solution is developed, comprising a fluorinated acyclic carbonate, an organosilicon compound, and lithium salts with oxalato-complex anions, which work together to reduce internal resistance and enhance high-temperature storage performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional electrolyte solutions are used, then battery capacity is maintained, but internal resistance increases and high-temperature storage performance deteriorates
Solution Approach 1:
The patent applies parameter changes by modifying the chemical composition parameters of the electrolyte solution. Specifically, it introduces a fluorinated cyclic carbonate compound with a fluorine content of 35-70 mass% and uses it in combination with specific additives (organosilicon compound, cyclic carbonate, and chain carbonate) at optimized concentrations. This chemical parameter modification enables the electrolyte to form stable protective films on electrodes, reducing internal resistance and improving high-temperature storage performance without sacrificing battery capacity.
Solution Approach 2:
The patent employs composite materials by creating a multi-component electrolyte system that combines fluorinated cyclic carbonate with organosilicon compounds, cyclic carbonates, and chain carbonates. This composite electrolyte formulation synergistically combines the benefits of each component: the fluorinated cyclic carbonate provides low internal resistance and thermal stability, while the other components contribute to capacity maintenance and overall stability. The composite approach resolves the contradiction by achieving both low internal resistance and good high-temperature performance simultaneously.
2Quantity of substance
If battery energy density is increased, then battery capacity improves, but thermal stability and safety performance worsen
Solution Approach 1:
The fluorinated cyclic carbonate compound acts as an intermediary substance that mediates between the electrodes and the electrolyte environment. It forms stable protective interface films on the electrodes that prevent harmful side reactions and thermal degradation, while still allowing efficient ion transport. This intermediary layer enables the battery to maintain high capacity while achieving improved thermal stability and safety performance.
Solution Approach 2:
The patent changes the physical and chemical parameters of the electrolyte by introducing fluorinated compounds with specific fluorine content (35-70 mass%). These parameter changes result in electrolyte solutions with improved thermal stability, lower viscosity, and better ion conductivity. The modified parameters allow the battery to achieve both high capacity and enhanced thermal safety.
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 electrolyte solution effectively minimizes internal resistance and maintains excellent high-temperature storage performance, leading to improved battery efficiency and reliability.
Implementation Method 1
a non-aqueous electrolyte solution containing a non-aqueous solvent and a lithium electrolyte
Implementation Method 2
a non-aqueous electrolyte solution containing: an electrolyte; a non-aqueous solvent
Data Source
AI summary
The invention provides an electrolyte solution capable of providing an electrochemical device, such as a lithium secondary battery, or module that has a small IV resistance value (internal resistance) and excellent high-temperature storage performance. The electrolyte solution contains: a solvent that contains a fluorinated acyclic carbonate having a fluorine content of 33 to 70 mass%; at least one organosilicon compound selected from the group consisting of a compound represented by the formula (1): (R11)n11-M11-O-SiR12R13R14 and a compound represented by the formula (2): R21R22R23-Si-F; a lithium salt (3) that contains an oxalato-complex as an anion; and a lithium salt (4) represented by the formula (4): LizM31FxOy.