Lithium-Ion Cathode Recycling With Chloroaluminate Ionic Liquids
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lithium-ion battery recycling methods face challenges such as high energy consumption, environmental hazards from corrosive reagents, and inefficiency in recovering lithium, leading to potential resource shortages and contamination.
Innovation Solution
The use of chloroaluminate ionic liquids or aluminum chloride solutions in organic solvents as a greener alternative for recycling lithium-ion battery cathode materials, enabling efficient extraction of lithium, cobalt, and other transition metals through reactions that form stable chlorides and amorphous compounds, which can be converted to insoluble aluminum oxide for separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If pyrometallurgical method is used for recycling, then high recycling efficiency for valuable metals is achieved, but lithium recovery is lost and high energy consumption occurs
Solution Approach 1:
The patent changes the fundamental parameter of the recycling process from high-temperature thermal treatment (pyrometallurgy) to low-temperature chemical leaching using ionic liquids. This parameter change enables lithium recovery while maintaining metal recycling efficiency and dramatically reducing energy consumption.
Solution Approach 2:
The patent introduces ionic liquids as an intermediary substance that facilitates the leaching and separation of metals from battery cathodes. This intermediary enables selective extraction of lithium, cobalt, and nickel without requiring high energy input, thus resolving the contradiction between efficiency and energy consumption.
2Productivity
If hydrometallurgy with corrosive reagents is used, then high recycling efficiency is achieved, but environmental harm and safety risks increase
Solution Approach 1:
The patent employs ionic liquids that can be easily disposed of or regenerated after use, replacing persistent corrosive acids. These ionic liquids perform the leaching function effectively and then can be discarded or processed without causing long-term environmental damage, thus maintaining efficiency while reducing harm.
Solution Approach 2:
The patent converts the potential harm of using strong reagents into a benefit by selecting ionic liquids that are both highly effective at metal extraction and environmentally benign. The reagent's strong leaching capability is maintained while its harmful effects are eliminated through careful selection of green chemistry materials.
3Speed
If conventional recycling methods are used, then processing speed is maintained, but lithium resource loss occurs leading to future shortages
Solution Approach 1:
The patent applies extraction by selectively removing lithium from the battery cathode material using ionic liquid leaching. This extraction process separates lithium from other metals, enabling its recovery and preventing resource loss while maintaining efficient processing speed through optimized leaching conditions.
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 method achieves 100% extraction efficiency for lithium and cobalt, 99.4% removal of aluminum content, and 99.7% recovery of cobalt, with low emissions and energy consumption, addressing the limitations of existing recycling techniques.
Implementation Method 1
tetrachloroaluminate anion (AlCl4−), present in a room temperature ionic liquid composed of 1:1 molar ratio of 1-ethyl-3-methylimidazolium chloride (EMIMCl) and aluminum chloride (AlCl3), can effectively extract lithium (Li) and cobalt (Co) from lithium cobalt oxide (LiCoO2) cathode in spent Li-ion batteries
Implementation Method 2
the strong affinity between AlCl4− and LiCoO2 can enable the extraction of lithium from LiCoO2 to form lithium chloride (LiCl)
Implementation Method 3
Co(III) in LiCoO2 is reduced to Co(II) by the oxide and oxygen gas is generated
Implementation Method 4
Co(III) in LiCoO2 is reduced to Co(II) by the oxide and oxygen gas is generated
Implementation Method 5
99.4% of the Al content (as AlCl4−) can be removed by converting aluminum oxychloride to Al oxide followed by water rinse
Implementation Method 6
The Al-containing compound can be converted to aluminum oxide that is insoluble in water by mild heat treatment at 150° C.
Implementation Method 7
cobalt can be subsequently recovered as cobalt hydroxide (Co(OH)2) at a 99.7% recovery rate
Data Source
AI summary
Various examples disclosed relate to methods for recycling lithium-ion battery cathode materials. The present disclosure includes methods that use ionic liquids, such as containing tetrachloroaluminate anions, or organic solutions of aluminum chloride, for recycling.