Lithium-Ion Battery Electrolyte Recycling via Supercritical CO2 Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for recycling electrolytic solutions from lithium ion batteries face high costs, complex separation processes, residual solvent issues, and low efficiency, especially when using supercritical CO2 due to weak polarity and low intersolubility.
Innovation Solution
A method involving cooling, disassembling, and crushing lithium ion batteries, followed by supercritical CO2 extraction with an entrainer, and using lithiated molecular sieves to adsorb impurities, resulting in a reusable electrolytic solution product.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If supercritical CO2 extraction is used to avoid residual solvent, then environmental safety is improved, but extraction efficiency deteriorates due to weak polarity and low intersolubility
Solution Approach 1:
The patent introduces an entrainer as an intermediary substance to facilitate the extraction process. The entrainer acts as a mediator between supercritical CO2 and the electrolytic solution components, enhancing the extraction efficiency by improving intersolubility while maintaining the environmental benefits of supercritical CO2 extraction.
Solution Approach 2:
The patent optimizes extraction parameters including pressure (25-35 MPa), temperature (40-55°C), and CO2 flow rate (5-10 mL/min) to enhance the solubility and extraction efficiency of supercritical CO2. By adjusting these parameters, the system overcomes the weak polarity limitation of CO2 while avoiding residual solvent issues.
2Productivity
If organic solvent extraction is used to improve extraction efficiency, then productivity is improved, but cost increases and residual solvent problems occur
Solution Approach 1:
The entrainer serves as an intermediary that enables efficient extraction without requiring large amounts of organic solvent. It facilitates the transfer of electrolytic solution components into the supercritical CO2 phase, achieving high extraction efficiency while eliminating the need for residual organic solvent removal.
Solution Approach 2:
The patent utilizes the phase transition properties of supercritical CO2, which can be easily converted from supercritical phase to gas phase by decompression. This phase transition allows for complete separation of the extracted components from the CO2, eliminating residual solvent issues while maintaining high extraction efficiency.
3Manufacturing precision
If multiple adsorption steps are added to remove impurities, then purity is improved, but device complexity increases
Solution Approach 1:
The patent segments the impurity removal process into distinct functional units: water removal unit, HF removal unit, and organic acid/alcohol removal unit. Each unit uses a specifically designed adsorbent material targeted at removing particular impurities, achieving high purity through modular, systematic treatment rather than complex integrated systems.
Solution Approach 2:
Different adsorbent materials with specific local properties are used for different impurity types: hydrophilic adsorbents for water, base-type adsorbents for HF, and specific molecular sieves for organic acids and alcohols. This localized optimization of adsorbent properties for specific impurities achieves high purity while keeping each treatment step relatively simple.
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 method effectively removes water, HF, organic acid, and alcohol impurities, enabling a reusable electrolytic solution with improved extraction efficiency and reduced environmental impact.
Implementation Method 1
adsorbing water in the extraction product using a 4 Å type lithiated molecular sieve, adsorbing HF in the extraction product using weak-base anion-exchange resin and adsorbing organic acid and alcohol in the extraction product using a 5 Å type lithiated molecular sieve
Implementation Method 2
extracting the electrolytic solution of the battery with introduction of the supercritical CO2
Implementation Method 3
collecting an extraction product with a cryogenic device
Data Source
AI summary
A method for recycling and treating an electrolytic solution of a lithium ion battery includes S1: cooling a fully discharged lithium ion battery below a freezing point of the electrolytic solution, and then disassembling and crushing the lithium ion battery to obtain a crushed solid containing the electrolytic solution, S2: under a protection of an inert gas, placing the crushed solid in a supercritical CO2 extraction instrument in which an entrainer is added; S3: conducting extraction; and S4: collection an extraction product with a cryogenic device, and adsorbing water in the extraction product using a 4 Å type lithiated molecular sieve, adsorbing HF in the extraction product using weak-base anion-exchange resin and adsorbing organic acid and alcohol in the extraction product using a 5 Å type lithiated molecular sieve.