Secondary Battery Electrode Lamination With Succinonitrile Binder
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The lamination process for secondary batteries, particularly for stack and stack/folding types, often damages separators and increases resistance due to high temperature and pressure, leading to poor adhesive forces between electrodes and separators.
Innovation Solution
A method involving an electrode slurry with succinonitrile is used, where succinonitrile acts as a binder between electrodes and separators, allowing for lower temperature and pressure lamination, minimizing damage and resistance by rearranging its distribution during drying and dissolving in the electrolyte solution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high temperature and high pressure are applied during lamination to improve adhesive force between negative electrode and separator, then adhesive force is improved, but binder melts and acts as resistance, deteriorating battery performance
Solution Approach 1:
The patent changes the chemical composition parameter of the binder from conventional materials (PVDF, CMC, SBR) to succinonitrile, which has a higher melting point and does not melt under lamination conditions. This parameter change allows the binder to maintain adhesive force without melting and forming resistance, thus resolving the contradiction between improving adhesive force and preventing resistance generation.
2Strength
If high pressure is applied during lamination to improve adhesive force of negative electrode, then adhesive force is improved, but pores of separator are reduced, increasing resistance
Solution Approach 1:
The patent changes the binder material parameter to succinonitrile, which provides sufficient adhesive force at lower pressures. This allows the lamination process to be performed at reduced pressure, preventing excessive compression of separator pores while still achieving strong adhesive bonding between the negative electrode and separator.
3Strength
If high temperature and high pressure are applied during lamination to secure adhesive force, then adhesive force is improved, but damage to separator occurs
Solution Approach 1:
The patent changes the binder material to succinonitrile, which maintains its binding properties at lower temperatures and pressures. This parameter change enables the lamination process to proceed under milder conditions, reducing thermal and mechanical stress on the separator and preventing damage while still achieving strong adhesive force.
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 enhances adhesive forces between electrodes and separators, reduces battery resistance, and lowers manufacturing costs by avoiding high-pressure processes, while maintaining battery performance.
Implementation Method 1
succinonitrile acts as a binder between electrodes and separators
Implementation Method 2
dissolving in the electrolyte solution
Data Source
Figure 1(a)~1(b)
Figure 2
Figure 3(a)~3(e)
AI summary
The present invention relates to a method for manufacturing a secondary battery having improved resistance, in which an electrode is manufactured using an electrode slurry comprising succinonitrile, and by which, compared to the prior art, an effect is achieved of, in a process for laminating the electrode with a separator, improving an adhesive force between the electrode and the separator even without requiring a high-pressure process. In addition, the succinonitrile in the electrode dissolves in an electrolyte, and thus an effect is achieved of improving the resistance of the battery.