Battery Electrolyte Fluoride Capture for Resistance Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In lithium-ion secondary batteries, the presence of fluoride ions generated from fluorine-containing electrolytes can cause malfunctions such as corrosion of electrode plates and decomposition of active materials due to reaction with water, leading to increased resistance and degradation.
Innovation Solution
Incorporating a capturing compound with a heterocyclic ring formed of carbon and nitrogen atoms, specifically cyclic amines or amides, into the electrolytic solution to capture fluoride ions, which are then retained within an imaginary sphere of appropriate diameter, thereby inhibiting their harmful effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If fluorine-containing electrolyte (LiPF6) is used, then ionic conductivity and battery performance are improved, but fluoride ions are generated that cause corrosion and decomposition leading to increased resistance
Solution Approach 1:
A capturing compound is introduced as an intermediary substance that selectively binds fluoride ions generated from LiPF6 decomposition. The capturing compound acts as a mediator between the fluorine-containing electrolyte and the electrode components, preventing direct harmful interactions while maintaining the beneficial ionic conductivity of the electrolyte system.
Solution Approach 2:
The harmful fluoride ions generated from electrolyte decomposition are converted from detrimental agents into captured, neutralized species. The capturing compound transforms the harmful F- ions into stable complexes, converting what would be corrosive byproducts into harmless bound states that no longer cause degradation.
2Reliability
If capturing compound is added to electrolytic solution, then fluoride ion capture ability is improved, but device complexity increases
Solution Approach 1:
The invention modifies the chemical composition parameters of the electrolyte by introducing specific capturing compounds with defined molecular structures (cyclic amines or cyclic amides with 5-7 membered rings). By controlling the concentration and structural parameters of the capturing compound, the system achieves effective fluoride ion capture while managing the complexity through parameter optimization rather than structural redesign.
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 use of these capturing compounds effectively reduces the concentration of fluoride ions, preventing corrosion and decomposition, thus enhancing the stability and performance of the battery by maintaining lower resistance and extending its lifespan.
Implementation Method 1
the capturing compound includes a heterocyclic ring formed of a plurality of carbon atoms and a plurality of nitrogen atoms... and is capable of capturing fluoride ions (F−)
Data Source
AI summary
A power storage device is provided with an electrolytic solution including an electrolyte of a fluorine-containing salt. The electrolytic solution includes at least one kind of a capturing compound, and the capturing compound includes a heterocyclic ring formed of a plurality of carbon atoms and a plurality of nitrogen atoms, is formed of a cyclic amine compound or a cyclic amide compound in which an imaginary sphere formed by the plurality of nitrogen atoms included in the heterocyclic ring has an imaginary sphere diameter of 0.11 to 0.24 nm, and is capable of capturing fluoride ions.