Method of producing electrode for secondary battery, electrode, and secondary battery including electrode

A method of producing an electrode for a secondary battery including any electrode current collector of positive and negative electrodes and an electrode active material layer, the method comprising:

• preparing a moisture powder formed of agglomerated particles containing at least an electrode active material, a binder resin, and a solvent, with a solid phase, a liquid phase, and a gas phase in at least 50 number % or more of the agglomerated particles forming a pendular state or a funicular state in the moisture powder;
• supplying the prepared moisture powder directly to the electrode current collector and forming a coating film composed of the supplied moisture powder on the electrode current collector, with a gas phase of the coating film being remained, with an average film thickness t1 (μm) of the coating film being 50 μm or more;
• transporting the coating film on the electrode current collector, in a transport direction, to a roll mold, and performing concavo-convex transfer by using the roll mold to form a plurality of grooves extending in a direction orthogonal to the transport direction on a surface part of the coating film so that a depth t2 (μm) of the grooves satisfies ( 9/10×t1)>t2;
• and
• drying the coating film on the electrode current collector to form an electrode active material layer,
• wherein
• the concavo-convex transfer is performed to the coating film while the coating film is still in a wet state and the gas phase of the coating film is maintained, and
• the drying is performed only after the concavo-convex transfer is completed.