Method for manufacturing electrode plates and method for manufacturing batteries

Abstract

To provide a method for manufacturing high-quality electrode plates, and a method for manufacturing batteries equipped with high-quality electrode plates. [Solution] The current collector foil of a negative electrode plate, which is an example of a product to be manufactured, has a main body and a tab. The main body has first and second ends that are opposite to each other, and the tab protrudes from the first end. In the manufacture of the negative electrode plate, an asphalt paste is applied to the coating area of ​​the current collector foil to form a coating film and then dried. The coating area is wider than the main body area between the first planned line which will be the first end and the second planned line which will be the second end. A first press is performed to compress the asphalt layer, and a first cut is performed to cut the current collector foil. In the first cut, the cut is made outside the outer edge of the tab, the first planned line, and the second planned line. The asphalt layer is further compressed and cut at the second planned line L2. Then, the asphalt paste is applied along the cut location in the first cut so as to provide a large area with a high basis weight of negative electrode material.

Claims

1. The current collector foil and the composite layer provided on the surface of the current collector foil, which consists of an electrode material containing at least an active material, The aforementioned current collector foil is The composite material layer is provided on the surface, and the main body portion has a first end and a second end facing the first end, A method for manufacturing an electrode plate having a tab protruding from the first end, A coating film is formed by coating a composite paste, in which the electrode material is dispersed in a solvent, onto the surface of the current collector foil before the tab, the first end, and the second end are formed, in a coating area wider than the main body area between the first planned line which will be the first end and the second planned line which will be the second end. The formed coating film is dried to form the composite layer by removing the solvent. After drying, the aforementioned composite layer is subjected to a first press, which compresses it in the thickness direction. With respect to the pre-tab current collector foil after the first press, a first cut is performed along the outer edge of the tab, the first planned line, and the second outer line which is located outside the second planned line when viewed from the main body region. The asphalt layer after the first cutting is subjected to a second press, which compresses it in the thickness direction. The current collector foil after the second press is subjected to a second cut along the second planned line. A method for manufacturing an electrode plate, wherein in forming the coating film, the composite paste is applied such that a large portion is provided in a strip-shaped first region including the first planned line and extending along the first planned line, and in a strip-shaped second region located outside the main body region and including the second outer line and extending along the second outer line, where the basis weight of the electrode material is greater than that of a reference region other than the first and second regions within the coating region.

2. A method for manufacturing an electrode plate according to claim 1, In forming the aforementioned coating film, A first coating is performed by applying the first asphalt paste as the asphalt paste to the coating area, A method for manufacturing an electrode plate, comprising: applying a second mixture paste as the mixture paste onto the first mixture paste applied to the first and second regions by the first coating; and performing a second coating on the area where the second mixture paste is applied, with the area being the large-volume portion.

3. A method for manufacturing an electrode plate according to claim 2, A method for manufacturing an electrode plate, wherein the second composite paste has a higher viscosity than the first composite paste.

4. A method for manufacturing an electrode plate according to claim 2, A method for manufacturing an electrode plate, wherein the second composite paste has a solid content NV that is 2 wt% or more higher than that of the first composite paste.

5. A method for manufacturing an electrode plate according to any one of claims 2 to 4, A method for manufacturing an electrode plate, comprising coating the second composite paste within the first region such that the large portion is intermittently provided in the longitudinal direction of the first region in the second coating process.

6. A method for manufacturing an electrode plate according to claim 5, A method for manufacturing an electrode plate in which the second coating is not applied to the area corresponding to the tab in the longitudinal direction of the first region.

7. A method for manufacturing an electrode plate according to any one of claims 1 to 4, A method for manufacturing an electrode plate, comprising coating the composite paste such that, in forming the coating film, the basis weight of the electrode material in the large portion is 3% or more and 5% or less than the basis weight of the electrode material in the reference region.

8. A method for manufacturing an electrode plate according to any one of claims 1 to 4, In the first press described above, the density of the portion designated as the excess in the composite layer is 1.2 g / cm³. ３ A method for manufacturing an electrode plate that compresses the composite material layer as follows:

9. The electrode body has a positive electrode plate and a negative electrode plate stacked together with a separator in between. The first electrode plate, which is either the positive electrode plate or the negative electrode plate, The current collector foil and the composite layer provided on the surface of the current collector foil, which consists of an electrode material containing at least an active material, The aforementioned current collector foil is The composite material layer is provided on the surface, and the main body portion has a first end and a second end facing the first end, A method for manufacturing a battery having a tab protruding from the first end, The first electrode plate, A coating film is formed by coating a composite paste, in which the electrode material is dispersed in a solvent, onto the surface of the current collector foil before the tab, the first end, and the second end are formed, in a coating area wider than the main body area between the first planned line which will be the first end and the second planned line which will be the second end. The formed coating film is dried to form the composite layer by removing the solvent. After drying, the aforementioned composite layer is subjected to a first press, which compresses it in the thickness direction. With respect to the pre-tab current collector foil after the first press, a first cut is performed along the outer edge of the tab, the first planned line, and the second outer line which is located outside the second planned line when viewed from the main body region. The asphalt layer after the first cutting is subjected to a second press, which compresses it in the thickness direction. The current collector foil after the second press is subjected to a second cut along the second planned line. In forming the coating film, the composite paste is applied such that a large portion is provided in a strip-shaped first region that includes the first planned line and extends along the first planned line, and in a strip-shaped second region located outside the main body region, which includes the second outer line and extends along the second outer line, where the basis weight of the electrode material is greater than that of the reference region other than the first and second regions within the coating region. A method for manufacturing a battery, comprising stacking the manufactured first electrode plate and a second electrode plate, which is the other of the positive electrode plate and the negative electrode plate, with the separator in between, to produce the electrode body.

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