Granulated Electrode Plate Lamination for Uniform Porosity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrode sheet preparation methods result in uneven pore distribution and thickness, leading to inconsistent discharge capacity and potential internal short circuits due to varying current densities and material separation during battery discharge.
Innovation Solution
A method involving mixing and granulating active material, conductive agent, and binder to form uniform particles, followed by diaphragm forming using a laminating machine with multiple rollers to ensure consistent thickness and porosity, enhancing adhesion and compaction density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional coating and drying methods are used to prepare electrode sheets, then the manufacturing process is simple, but the pore distribution inside the electrode sheet is uneven, resulting in different current densities in different regions
Solution Approach 1:
The patent applies preliminary action by performing granulation of the electrode material before coating onto the current collector. The mixed particles are pre-formed with uniform pore distribution through granulation in a solution, ensuring that the pore structure is established before the coating and drying stages. This preliminary granulation step prevents the pore distribution problems that would otherwise occur during conventional coating and drying processes.
2Manufacturing precision
If conventional coating and drying methods are used, then the process is straightforward, but the thickness of the electrode sheet is uneven, leading to inconsistent discharge capacity
Solution Approach 1:
The granulation step is performed in advance to create uniformly sized particles with consistent morphology. These pre-formed granulated particles then coat more evenly on the current collector during the subsequent coating process, resulting in more uniform electrode sheet thickness. The preliminary granulation ensures that particles pack and distribute uniformly, reducing thickness variations.
Solution Approach 2:
The patent changes the physical state and size parameters of the electrode material by granulating it into uniform particles with controlled size distribution (0.5-5 μm). This parameter change in particle size and morphology enables more uniform coating and thickness control in the final electrode sheet, addressing the thickness uniformity issue.
3Reliability
If conventional electrode preparation is used, then manufacturing is simple, but powder dropping occurs during discharge, increasing resistance and causing internal short circuits
Solution Approach 1:
The granulation process is performed beforehand to create particles with improved surface characteristics and binding properties. These granulated particles have better adhesion to the current collector and maintain stronger bonding during the discharge process, preventing powder dropping and the associated reliability issues like increased resistance and internal short circuits.
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 achieves improved discharge capacity, especially at larger currents and lower temperatures, with enhanced uniformity and reduced risk of internal short circuits, while maintaining high compaction density and process automation.
Implementation Method 1
performing diaphragm forming on the mixed particles and a current collector in a laminating machine to obtain the electrode sheet
Implementation Method 2
mixing and granulating an active material, a conductive agent and a binder to obtain mixed particles
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The present application provides an electrode plate and a preparation method therefor, and a battery. The preparation method comprises the following steps: (1) mixing and granulating an active substance, a conductive agent, a solvent and a binder to obtain mixed particles; and (2) performing lamination on the mixed particles in step (1) and a current collector in a laminator to obtain an electrode plate, wherein the laminator has three or more rollers.