Lithium-Air Battery Charging Liquid for Fast Peroxide Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Air batteries, particularly lithium air batteries, face challenges with unfavorable charge/discharge cycle characteristics due to the low electron conductivity of discharge products like lithium peroxide, leading to prolonged charge times and electrode degradation.
Innovation Solution
A method involving a nonaqueous electrolyte liquid with a lithium salt, where the battery is discharged and then supplied with a charging liquid that desorbs the solid discharge product from the positive electrode, reducing the need for full decomposition and minimizing current flow through the electrode, thereby shortening charge time and preventing electrode degradation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional electrochemical charging is used to decompose lithium peroxide, then the discharge product can be decomposed, but the charge time becomes extremely long due to low electron conductivity of lithium peroxide
Solution Approach 1:
The patent introduces a redox mediator as an intermediary substance that facilitates the charge reaction. The redox mediator chemically decomposes lithium peroxide through chemical reactions rather than direct electrochemical decomposition, bypassing the electron conductivity limitation. This mediator acts as a bridge between the discharge product and the charging process, enabling faster charge times without requiring high electron conductivity of the discharge product itself.
Solution Approach 2:
The patent changes the charging mechanism from direct electrochemical decomposition to chemical decomposition using a redox mediator. This parameter change in the charging approach allows the system to overcome the fundamental limitation of lithium peroxide's low electron conductivity, transforming the charging process into a chemically-driven reaction that proceeds much faster.
2Productivity
If continuous charge current is applied to decompose discharge products, then charging can be achieved, but the positive electrode undergoes degradation and loses performance
Solution Approach 1:
The patent replaces the mechanical/electrochemical charging process with a chemical charging process using a redox mediator. Instead of applying continuous electrical current that mechanically stresses the electrode structure, the system uses chemical reactions to decompose discharge products, thereby preserving the electrode's structural integrity and preventing degradation.
Solution Approach 2:
The redox mediator serves as an intermediary that performs the decomposition function without requiring direct passage of charge current through the positive electrode. This mediator absorbs the chemical transformation burden, protecting the electrode from the harmful effects of continuous electrochemical stress while maintaining charging capability.
3Loss of time
If high charge current is used to speed up charging, then charge time is reduced, but the discharge product decomposition becomes incomplete and electrode performance deteriorates
Solution Approach 1:
The patent fundamentally changes the charging parameter from electrochemical current-driven decomposition to chemical mediator-driven decomposition. This parameter change enables complete decomposition of discharge products at lower current densities, avoiding the trade-off between charge speed and decomposition completeness that plagues conventional electrochemical charging.
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 significantly reduces charge time and suppresses electrode degradation, allowing for faster charging and stable long-term energy supply while maintaining the porous structure of the positive electrode.
Implementation Method 1
supplying a charging liquid different from the nonaqueous electrolyte liquid from the outside to the inside of the air battery so that a discharge product generated by the discharging is desorbed from the positive electrode
Implementation Method 2
lithium peroxide is chemically decomposed by injecting as a charging liquid, an electrolyte liquid containing an oxide of a redox mediator
Data Source
AI summary
A charge/discharge method of an air battery is a charge/discharge method of an air battery including a positive electrode, a negative electrode, and a nonaqueous electrolyte liquid containing a nonaqueous solvent and a lithium salt dissolved in the nonaqueous solvent, the nonaqueous electrolyte liquid being interposed between the positive electrode and the negative electrode, the charge/discharge method includes: discharging the air battery; and supplying a charging liquid different from the nonaqueous electrolyte liquid from the outside to the inside of the air battery so that a discharge product generated by the discharging is desorbed from the positive electrode while being in the form of a solid.