Rotary Firing Recovery of Battery Active Material Without Acid Leaching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for recycling lithium secondary battery active materials are not environmentally friendly and require costly neutralization and wastewater treatment processes, and fail to recover lithium effectively, often using toxic solvents and complex processes.
Innovation Solution
A rotary firing apparatus with a heat treatment bath and screening wall is used to recover lithium composite transition metal oxide active materials from scrap electrodes by removing binders and conductive materials through heat treatment, allowing for the separation of active materials from current collectors without acid dissolution, and subsequent annealing and cleaning steps to restore their properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of substance
If acid dissolution method is used to extract active material elements, then active material recovery is achieved, but environmental pollution increases and process cost rises due to neutralization and wastewater treatment
Solution Approach 1:
The patent replaces the chemical dissolution system with a mechanical separation system. Specifically, it uses a classification device with a classification blade that mechanically separates active material particles from electrode scrap based on size and shape differences, eliminating the need for acid dissolution, neutralization, and wastewater treatment processes
Solution Approach 2:
The patent extracts and removes harmful chemical substances (acids, solvents) from the recovery process. By using mechanical classification to directly separate active material from electrode scrap, the method extracts only the desired active material particles while leaving behind binders and conductive materials, avoiding environmental pollution entirely
2Loss of substance
If acid dissolution method is used to extract active material elements, then active material recovery is achieved, but process cost increases due to neutralization and wastewater treatment processes
Solution Approach 1:
The patent replaces complex chemical processing systems with a simple mechanical classification system. The classification device uses a rotationally operating classification blade to separate active material particles, eliminating the need for expensive acid dissolution, neutralization, and wastewater treatment infrastructure
Solution Approach 2:
The patent selectively recovers only the valuable active material particles while discarding binders and conductive materials as waste. This selective recovery approach avoids the costly process of extracting and purifying individual metal elements from dissolved electrodes
3Loss of substance
If conventional recycling methods are used, then active material elements are extracted, but the process becomes complex requiring multiple steps
Solution Approach 1:
The patent replaces multiple complex chemical processing steps (dissolution, filtration, precipitation, purification) with a single mechanical classification operation. The classification device performs the entire separation process in one step, dramatically simplifying the recovery process
Solution Approach 2:
The patent merges the separation and recovery operations into a single integrated process. The classification device simultaneously separates active material from electrode scrap and collects the recovered particles, combining what would traditionally require multiple discrete process steps
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 enables the efficient and eco-friendly recovery of active materials with high recovery rates, reducing environmental impact and production costs, while maintaining the electrochemical performance of the recovered materials.
Implementation Method 1
the heat treatment bath removes a binder and a conductive material in an active material layer by performing heat treatment in an air on an electrode scrap comprising the active material layer on a current collector
Implementation Method 2
an active material in the active material layer passes through the screening wall and is recovered as an active material in powder form, and the current collector that does not pass through the screening wall is recovered separately
Implementation Method 3
performing heat treatment in an air on an electrode scrap... removes a binder and a conductive material in an active material layer
Data Source
AI summary
An active material recovery apparatus includes a heat treatment bath and a screening wall extending along a first axis. The heat treatment bath includes a heating zone and the screening wall includes a cooling zone. The active material recovery apparatus includes an exhaust injection and a degassing system. The heat treatment bath is configured to remove a binder and a conductive material in an active material layer and to perform heat treatment in air on an electrode scrap including the active material layer on a current collector. The screen wall is configured to recover the active material in powder form. The active material recovery apparatus is configured to separately recover the current collector that does not pass through the screening wall. The heat treatment bath includes protrusions in a sawtooth shape on a first cross-section orthogonal to the first axis.