ELECTRODE FOR SECONDARY BATTERY AND METHOD FOR PRODUCING THE SAME

Abstract

This secondary battery electrode is provided with a core material configured from a metal foil that softens at less than or equal to 200° C. and an electrode mixture sheet which is bonded on the surface of the core material. The electrode mixture sheet includes an active material and a fibrous binder, and the active material bites into the core material, with the maximum bite depth at least 30% of the thickness of the core material. The fibrous binder may for example have polytetrafluoroethylene as the main component.

Description

Claims

1. An electrode for a secondary battery, comprising: a core constituted with a metal foil that softens at 200° C. or lower; andan electrode mixture sheet joined to a surface of the core, wherein the electrode mixture sheet includes an active material and a fibrous binder, andthe active material is embedded in the core and a maximum embedded depth is 30% or more of a thickness of the core.

2. The electrode for a secondary battery according to claim 1, wherein the fibrous binder is mainly composed of polytetrafluoroethylene.

3. The electrode for a secondary battery according to claim 1, wherein the core is an aluminum alloy foil containing 1.2 to 1.7 mass% of iron.

4. The electrode for a secondary battery according to claim 1, wherein a melting point of the fibrous binder is higher than a softening point of the core by 100° C. or more.

5. A method of manufacturing an electrode for a secondary battery, the method comprising: mixing an active material and a fibrous binder without a solvent to produce an electrode mixture having a solid content concentration of substantially 100%;rolling the electrode mixture and forming into a sheet to produce an electrode mixture sheet; anddisposing the electrode mixture sheet on a surface of a core constituted with a metal foil that softens at 200° C. or lower, and heat-pressing a stacked body of the electrode mixture sheet and the core at a temperature equal to or lower than a melting point of the fibrous binder.

6. The method of manufacturing an electrode for a secondary battery according to claim 5, wherein the heat-pressing is performed at a temperature that is equal to or higher than a temperature at which the core softens and at a temperature that is equal to or lower than the melting point of the fibrous binder.

7. The method of manufacturing an electrode for a secondary battery according to claim 5, wherein the heat-pressing is performed at a temperature that is equal to or higher than a temperature at which the core softens and at a temperature that is lower than the melting point of the fibrous binder by 50° C. or more.