Method for manufacturing secondary battery and secondary battery

Abstract

The present invention provides a method for manufacturing a secondary battery, which comprises: a step of preparing an electrode group (4) in which a positive electrode plate (1) and a negative electrode plate (2) are arranged opposite to each other via a porous insulating layer in such a manner that an end portion (1a, 2a) of at least one of the positive electrode plate (1) and the negative electrode plate (2) projects beyond the porous insulating layer; a step of preparing a collector plate (10), a major surface of which is provided with a plurality of projections (11) each having an apex; a step of bringing the end portion (1a, 2a) of the electrode plate projecting beyond the porous insulating layer into contact with the other major surface of the collector plate (10); and a step wherein a projection (11) is melted by an arc discharge toward the apex of the projection (11) and the end portion (1a, 2a) of the electrode plate and the collector plate (10) are welded to each other by a molten member (12) that is the molten projection (11).

Description

technical field

[0001] The present invention relates to a method for manufacturing a secondary battery having an electrode group with a so-called "tabless structure", a current collector plate used in the manufacturing method, and a secondary battery having an electrode group with a tabless structure. Background technique

[0002] With the miniaturization of portable electronic equipment, lithium-ion secondary batteries and nickel-metal hydride storage batteries are widely used as their power sources. In recent years, these batteries have been used as power sources that require vibration resistance and high current, such as electric tools and hybrid vehicles. Also attracted much attention. Therefore, there is an increasing demand for small, lightweight and high-output secondary batteries regardless of the shape of the battery, such as a cylindrical shape or a flat shape, in order to be able to cope with various types of use equipment.

[0003] The electrode group with no ta...

Examples

Embodiment 1

[0074] (1) Production of positive plate

[0075] First, 85 parts by weight of lithium cobaltate powder was prepared as a positive electrode active material, 10 parts by weight of carbon powder was prepared as a conductive material, and 5 parts by weight of polyvinylidene fluoride (PVdF) was prepared as a binder. Then, the prepared positive electrode active material, conductive material and binding material are mixed to prepare the positive electrode mixture coating.

[0076] Next, the positive electrode mixture paint was applied to both surfaces of the positive electrode current collector of an aluminum foil having a thickness of 15 μm and a width of 56 mm, and the positive electrode mixture paint was dried. Then, the positive electrode mixture layer 1 b coated with the positive electrode mixture paint was rolled to form a positive electrode plate 1 with a thickness of 150 μm. At this time, the width of the positive electrode mixture layer 1 b was 50 mm, and the width of the ...

Embodiment 2

[0094] (1) Production of positive plate

[0095] First, 85 parts by weight of lithium cobaltate powder was prepared as a positive electrode active material, 10 parts by weight of carbon powder was prepared as a conductive material, and 5 parts by weight of polyvinylidene fluoride (PVdF) was prepared as a binder. Then, the prepared positive electrode active material, conductive material, and binder were mixed to prepare a positive electrode mixture coating.

[0096] Next, the positive electrode mixture paint was applied to both surfaces of the positive electrode current collector of an aluminum foil having a thickness of 15 μm and a width of 83 mm. After the positive electrode mixture paint was dried, the positive electrode mixture layer 1 b was rolled to produce a positive electrode plate 1 with a thickness of 83 μm. At this time, the width of the positive electrode mixture layer 1 b was 77 mm, and the width of the non-coated portion 1 a of the positive electrode mixture was ...

technical field

[0001] The present invention relates to a method for manufacturing a secondary battery having an electrode group with a so-called "tabless structure", a current collector plate used in the manufacturing method, and a secondary battery having an electrode group with a tabless structure. Background technique

[0002] With the miniaturization of portable electronic equipment, lithium-ion secondary batteries and nickel-metal hydride storage batteries are widely used as their power sources. In recent years, these batteries have been used as power sources that require vibration resistance and high current, such as electric tools and hybrid vehicles. Also attracted much attention. Therefore, there is an increasing demand for small, lightweight and high-output secondary batteries regardless of the shape of the battery, such as a cylindrical shape or a flat shape, in order to be able to cope with various types of use equipment.

[0003] The electrode group with no ta...

Examples

Embodiment 1

[0074] (1) Production of positive plate

[0075] First, 85 parts by weight of lithium cobaltate powder was prepared as a positive electrode active material, 10 parts by weight of carbon powder was prepared as a conductive material, and 5 parts by weight of polyvinylidene fluoride (PVdF) was prepared as a binder. Then, the prepared positive electrode active material, conductive material and binding material are mixed to prepare the positive electrode mixture coating.

[0076] Next, the positive electrode mixture paint was applied to both surfaces of the positive electrode current collector of an aluminum foil having a thickness of 15 μm and a width of 56 mm, and the positive electrode mixture paint was dried. Then, the positive electrode mixture layer 1 b coated with the positive electrode mixture paint was rolled to form a positive electrode plate 1 with a thickness of 150 μm. At this time, the width of the positive electrode mixture layer 1 b was 50 mm, and the width of the ...

Embodiment 2

[0094] (1) Production of positive plate

[0095] First, 85 parts by weight of lithium cobaltate powder was prepared as a positive electrode active material, 10 parts by weight of carbon powder was prepared as a conductive material, and 5 parts by weight of polyvinylidene fluoride (PVdF) was prepared as a binder. Then, the prepared positive electrode active material, conductive material, and binder were mixed to prepare a positive electrode mixture coating.

[0096] Next, the positive electrode mixture paint was applied to both surfaces of the positive electrode current collector of an aluminum foil having a thickness of 15 μm and a width of 83 mm. After the positive electrode mixture paint was dried, the positive electrode mixture layer 1 b was rolled to produce a positive electrode plate 1 with a thickness of 83 μm. At this time, the width of the positive electrode mixture layer 1 b was 77 mm, and the width of the non-coated portion 1 a of the positive electrode mixture was ...

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