Lithium Metal Electrode Cutting With Protective Layers and Ultrasonics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electrode assemblies face issues with deformation due to stress accumulation during charge and discharge, leading to uneven spacing between electrodes and safety risks, and the processing of lithium metal for stacked-folded electrode assemblies is challenging due to its high ductility and viscosity, affecting productivity.
Innovation Solution
A method involving the use of protective layers and precise cutting techniques, such as ultrasonication, to process longitudinally extended lithium metal for negative electrodes in stacked-folded electrode assemblies, minimizing defects like adhesion and wrinkling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If lithium metal is processed by conventional cutting methods, then the electrode assembly can be manufactured, but the high ductility and viscosity of lithium metal cause processing difficulties and defects
Solution Approach 1:
The patent replaces conventional mechanical cutting methods with ultrasonic vibration cutting. The ultrasonic cutter generates high-frequency vibrations that reduce the mechanical stress on lithium metal during cutting, preventing defects caused by lithium's high ductility and viscosity. This substitution of mechanical cutting with ultrasonic vibration solving the processing difficulty while maintaining reliability.
Solution Approach 2:
The ultrasonic cutter applies periodic high-frequency vibrations during the cutting process. This periodic action creates micro-impacts that facilitate clean cutting of lithium metal without causing deformation or adhesion defects, directly addressing the processing challenges posed by lithium's material properties.
2Productivity
If conventional cutting methods are used on lithium metal, then processing can be performed, but defects like adhesion and wrinkling occur
Solution Approach 1:
The ultrasonic vibration cutting system replaces conventional mechanical cutting, enabling faster processing speeds while simultaneously reducing defects. The high-frequency vibrations allow the cutter to rapidly remove material without causing adhesion or wrinkling, thus improving both productivity and manufacturing precision.
Solution Approach 2:
The patent employs mechanical vibration through ultrasonic frequencies during cutting. This vibration prevents the cutter from sticking to the lithium metal surface, eliminating adhesion defects, and reduces wrinkling by creating clean separation. The vibrational energy enables high-speed cutting with high precision.
3Ease of manufacture
If jelly-roll electrode assembly structure is used, then electrode assembly can be formed, but stress accumulation during charge and discharge causes deformation
Solution Approach 1:
The patent introduces a stress relief groove that segments the electrode assembly structure, creating a dedicated region for stress accumulation. This segmentation allows the assembly to maintain its overall structure while providing a specific zone that absorbs expansion and contraction stresses, preventing deformation and maintaining electrode spacing stability.
Solution Approach 2:
The stress relief groove acts as an intermediary element between the electrodes and the external environment. It mediates the stress generated during charge and discharge by providing a controlled path for stress relief, thereby protecting the electrode spacing from deformation while maintaining the jelly-roll structure's manufacturing advantages.
4Volume of moving object
If jelly-roll electrode assembly is wound densely, then space efficiency is improved, but winding speed decreases and productivity is reduced
Solution Approach 1:
The patent introduces the stress relief groove during the electrode formation process, before assembly. This preliminary action prepares the electrode structure to accommodate future stress, enabling faster winding speeds without compromising the ability to maintain dense packing and space efficiency in the final assembly.
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 enhances the processing speed and suitability for mass production of lithium metal, ensuring high reliability and improved battery performance by reducing defects and stress-related issues.
Implementation Method 1
cutting the lithium metal by pressurizing the supplied raw materials with a cutter on the first and second protective layers
Implementation Method 2
precise cutting techniques, such as ultrasonication, to process longitudinally extended lithium metal
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A method of processing lithium metal for the negative electrode of an electrode assembly is provided. The processing method comprises the steps of: supplying raw materials by separating a first raw material comprising lithium metal bonded with a first protective layer on one side, and a second raw material comprising a second protective layer, so that the lithium metal is located between the first and second protective layers; cutting the lithium metal by pressurizing the supplied raw materials with a cutter on the first and second protective layers; and recovering the raw materials by separating the first and second raw materials after cutting. The method of processing lithium metal according to one embodiment of the present invention is effective for processing longitudinally extended lithium metal that is applied as a negative electrode in a stacked-folded electrode assembly, and can produce highly reliable processed lithium metal.