Vibrating Calender Roller for Battery Electrode Manufacturing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing calendering processes for battery electrodes face issues such as wrinkling, delamination, and high friction, leading to defects and inefficiencies, particularly due to high stress concentrations and frictional forces during the compression of active materials, which affect the quality and performance of lithium-ion battery cells.
Innovation Solution
A vibration-assisted calendering method and device are employed, where at least one roll of the calender is excited to oscillate, reducing friction and stress concentrations through a 'stick and slip' effect, and creating micro-textures on the electrode surface to enhance electrolyte wetting and reduce adhesion to the rollers, thereby minimizing wrinkles and delamination without the need for heating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If high compression force is applied during calendering to increase specific capacitance and electrical conductivity, then the porosity of active material is reduced and density is increased, but stress concentration causes cracks and particle breakage in the active material
Solution Approach 1:
The patent applies ultrasonic vibration to the calender roller surface during the calendering process. This vibration creates a 'stick-slip' effect that reduces friction between the roller and active material, allowing high compression forces to be applied without causing excessive stress concentration. The vibration frequency is specifically chosen to resonate with the roller, amplifying the effect and preventing particle breakage while achieving the desired density increase.
Solution Approach 2:
The patent changes the physical state of the calender roller from stationary to vibrating by introducing ultrasonic frequency oscillations. This parameter change transforms the calendering process from a purely mechanical compression process to one that incorporates dynamic vibration, fundamentally altering the stress distribution and friction characteristics during compression.
2Manufacturing precision
If high compression force is applied during calendering to densify the active material coating, then specific capacitance is increased, but friction between the active material and roller increases leading to adhesion and delamination
Solution Approach 1:
Ultrasonic vibration of the calender roller creates continuous micro-separation between the roller surface and active material during compression. This vibration-induced 'stick-slip' motion dramatically reduces friction and prevents adhesion, allowing high compression forces to be applied without causing delamination or excessive friction-related defects.
Solution Approach 2:
The patent converts the potentially harmful high friction and adhesion forces into beneficial effects by using ultrasonic vibration. The vibration energy transforms the sticking tendency into a controlled stick-slip motion that actually improves the calendering process by preventing delamination while maintaining high compression for densification.
3Manufacturing precision
If the uncoated substrate material is not stretched in the conveying direction during calendering, then the coating area is preserved, but compressive stresses in the transverse direction cause wrinkling in the uncoated area
Solution Approach 1:
The ultrasonic vibration applied to the calender roller during calendering reduces the frictional forces that would otherwise cause the uncoated substrate material to wrinkle under compressive stress. The vibration creates a lubricating effect that allows the substrate to maintain its shape and flatness even in the uncoated areas where no tensile stress is applied to counteract the compressive forces.
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 approach reduces calendering force, minimizes wrinkles and delamination, improves surface quality, and increases the density of the active material, resulting in higher electrical conductivity and volumetric energy density without the need for additional heating or complex cleaning processes.
Implementation Method 1
at least one roller of the calender is excited to vibration by a vibration device
Implementation Method 2
reducing friction and stress concentrations through a 'stick and slip' effect
Implementation Method 3
creating micro-textures on the electrode surface to enhance electrolyte wetting
Implementation Method 4
compact the active material arranged on the carrier material... The active material is compressed by at least 20%
Implementation Method 5
high friction, leading to defects and inefficiencies, particularly due to high stress concentrations and frictional forces
Implementation Method 6
reducing adhesion to the rollers
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Method for manufacturing an electrode (1) of a battery cell (2); wherein the method comprises at least the following steps: a) providing an electrode (1) comprising a carrier material (4) at least partially coated with an active material (3); b) conveying the electrode (1) along a conveying direction (5) and compacting the active material (3) by means of at least one calender (6); wherein the electrode (1) has an uncoated first region (8) at an edge (7) extending parallel to the conveying direction (5); wherein at least one roller (9) of the calender (6) is excited to vibrations (11) via a vibration device (10). Device (17) for manufacturing an electrode (1) of a battery cell (2), wherein the electrode (1) comprises a carrier material (4) at least partially coated with an active material (3) and the device (17) is suitably configured for compacting the active material (3).