Method for manufacturing electrode for secondary battery and electrode manufactured thereby
The present invention provides a method for manufacturing an electrode, the method comprising the steps of: preparing a lump of mixture bulk; milling the mixture bulk to prepare granular powder having an average particle diameter of 30 micrometers to 180 micrometers; sprinkling the granular powder on the surface of a metal current collector; and rolling the granular powder on the metal current collector to laminate the granular powder on the metal current collector.
1. A method of manufacturing an electrode for a secondary battery, comprising:
preparing a mixture bulk of a lump form;
milling the mixture bulk to prepare a granular powder having an average particle size of 30 micrometers to 180 micrometers;
scattering the granular powder on a surface of a metal current collector; and
rolling the granular powder on the metal current collector, and laminating the granular powder on the metal current collector,
wherein the preparing of the mixture bulk comprises:
forming a first mixture by mixing a first binder, an electrode active material, and a conductive material;
mixing a second binder with the first mixture to form a second mixture; and
applying a shear stress to the second mixture to fiberize the second binder to obtain the mixture bulk of a lump form in which the fibrous second binder is entangled in the second mixture; and
wherein a Hausner ratio of the granular powder is between 1.10 and 1.25
wherein a content of the second binder is not less than 0.8% and not more than 1% based on total weight of the mixture bulk;
wherein a content of the first binder is not less than 2.1% and not more than 2.4% based on a total weight of the mixture bulk.
2. The method of claim 1 , wherein the second binder is polytetrafluoroethylene (PTFE).
3. The method of claim 1 , wherein the first binder is one or more selected from the group consisting of polyethylene oxide (PEO), polyvinylidene fluoride (PVdF), and polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP).
4. The method of claim 1 , wherein the electrode active material is a positive electrode active material.
5. The method of claim 1 , wherein the electrode active material is a negative electrode active material.
6. The method of claim 1 , wherein the laminating comprises:
rolling the granular powder on the metal current collector by a roller heated to a predetermined temperature, to produce a rolled granular powder; and
attaching the rolled granular powder to the current collector by using the pressure and temperature of the roller.
7. The method of claim 6 , wherein the attaching is performed as at least one of the first binder and the second binder contained in the granular powder is melted.