Electrode with enhanced performance and electrochemical device comprising the same

Abstract

Disclosed is an electrode slurry comprising: (a) an electrode active material capable of lithium intercalation / deintercalation; and (b) monomers capable of forming a polymer via polymerization. An electrode having a binder polymer formed by applying the electrode slurry onto a current collector and carrying out in situ polymerization of the monomers, and an electrochemical device comprising the electrode are also disclosed. The electrode uses monomers capable of forming a binder polymer via polymerization under heat or light upon drying of the electrode, instead of the conventional PVdF or SBR-based binders. Therefore, it is possible to simplify a process for manufacturing an electrode, to provide an eco-friendly electrode by virtue of the use of an aqueous solvent as a dispersion medium, to improve the ion conductivity of a binder by virtue of the use of a solvent for a battery electrolyte as a dispersion medium, and thus to improve the quality of an electrochemical device.

Description

technical field [0001] The present invention relates to an electrode with improved quality and no damage to the ecological environment, which replaces the recently used polymeric binder by using a monomer that is dried and polymerized to form a binder polymer during the manufacture of the electrode, thereby reducing the Simple way to manufacture electrodes. The invention also relates to a method of manufacturing an electrode, and an electrochemical device comprising the electrode. Background technique [0002] In recent years, portable electronic devices, such as portable computers, cellular phones, and camcorders, have been steadily developed to reduce the size and weight of products, and lithium secondary batteries used as driving energy for electronic devices are also required to be downsized and lightened. weight. [0003] A lithium secondary battery includes a cathode, an anode, and an electrolyte. After the first charge cycle, lithium ions are released from the cath...

AI Technical Summary

Problems solved by technology

Among such binders, polyvinylidene fluoride-based binders require the use of non-aqueous toxic solvents, such as N-methylpyrrolidone (NMP), as the dispersion medium for electrode pastes, so there is a potential risk of environmental pollution

In addition, such binders may lead to degradation of battery quality when the dispersion medium cannot be completely removed from the electrode paste after it is coated on the current collector

Therefore, an additional step of removing the dispersion medium must be added

At the same time, even after the electrode is completed, the polar electrolyte cannot easily penetrate into the electrode active material particles, resulting in an increase in the interface resistance of the electrode and an increase in the internal resistance of the battery, resulting in a decrease in battery quality

Furthermore, in order to allow the polar electrolyte to penetrate into the electrode, it takes a long time and complicated process conditions so that the electrode can be wetted by the electrolyte

In this case, smooth conduction of lithium ions cannot be achieved, resulting in lower battery quality

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