Battery Thermal Opening in a Reducing Atmosphere
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The increasing demand for electrochemical energy storage devices, particularly lithium-ion batteries, results in a growing number of end-of-life batteries and production waste, necessitating a cost-effective and scalable method for recovering valuable materials as secondary raw materials, while posing challenges due to thermal reactivity and the risk of ignition.
Innovation Solution
A thermal treatment method using an indirectly heated furnace under atmospheric pressure with a reducing atmosphere, which controls the thermal treatment process by managing the reducing atmosphere and suction of gaseous products, allowing for continuous processing and reducing the formation of metal oxides, thereby simplifying downstream processing and increasing throughput.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If directly heated rotary kilns are used for thermal opening, then throughput can be increased, but metal oxides form requiring complex downstream processing
Solution Approach 1:
The patent applies an indirectly heated furnace that creates a reducing atmosphere (inert environment) during thermal treatment. This prevents oxidation of metal components by excluding oxygen from the treatment chamber, thereby producing metallic materials instead of metal oxides. This eliminates the need for complex oxide reduction processes in downstream processing while maintaining high throughput capability.
Solution Approach 2:
The patent replaces direct heating (mechanical/thermal contact) with indirect heating through a reducing atmosphere. Instead of direct flame or contact heating that causes oxidation, the system uses thermal radiation and conduction through the furnace walls to heat materials in an oxygen-deprived environment, substituting a chemical process (oxidation) with a physical process (thermal treatment in inert atmosphere).
2Productivity
If thermal treatment temperature is increased to improve processing speed, then throughput increases, but metal melting occurs reducing recovery quality
Solution Approach 1:
The indirectly heated furnace maintains a reducing atmosphere that prevents metal oxidation and allows precise temperature control. By creating an inert environment, the system can operate at optimal temperatures for thermal decomposition without risking metal melting or unwanted chemical reactions, thereby maintaining material recovery quality while achieving efficient processing speeds.
Solution Approach 2:
The patent utilizes parameter changes in the thermal treatment process, specifically controlling temperature gradients and atmosphere composition. By adjusting these parameters within the indirectly heated furnace, the system achieves complete decomposition of organic materials and electrolytes while keeping metal temperatures below melting points, thus maintaining recovery quality.
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 safe and efficient thermal opening of electrochemical energy storage devices, reducing the need for additional oxide separation steps, increasing throughput, and lowering costs by utilizing residual charge as an energy source, while maintaining a reducing atmosphere to minimize thermal reactivity and oxide formation.
Implementation Method 1
indirectly heated furnace
Implementation Method 2
indirectly heated furnace
Implementation Method 3
reducing atmosphere
Implementation Method 4
suction device for suctioning off gaseous evaporation and decomposition products
Implementation Method 5
thermal post-combustion system to clean the gases suctioned out of the treatment chamber with heat recovery
Implementation Method 6
gaseous evaporation and decomposition products that develop during the thermal treatment
Implementation Method 7
thermal (pyrolytic) treatment of the energy storage devices
Data Source
AI summary
A method for opening up electrochemical energy storage devices in connection with a subsequent recovery of valuable materials contained therein as secondary raw materials, in which method the energy storage devices are opened up by a thermal treatment system to remove the electrolytes and reactive substances, before the thermally treated material is subjected to processing, whereby secondary raw materials in the thermally treated material are separated from one another. The thermal treatment is performed in an indirectly heated furnace under atmospheric pressure conditions or a slight overpressure relative to the ambient pressure of up to 20 mbar in a reducing atmosphere, and influence is exerted on the course of the thermal treatment process via the reducing atmosphere, as a control variable. Furthermore, a thermal treatment system is described for removing electrolytes and reactive substances in electrochemical energy storage devices and consequently for pyrolytic opening.