WO2018190691A1

WO2018190691A1 - Secondary battery and secondary battery manufacturing method

Info

Publication number: WO2018190691A1
Application number: PCT/KR2018/004366
Authority: WO
Inventors: 김재웅; 김형권; 김상욱
Original assignee: 주식회사 엘지화학
Priority date: 2017-04-14
Filing date: 2018-04-13
Publication date: 2018-10-18

Abstract

The present invention relates to a secondary battery and a secondary battery manufacturing method, wherein the mechanical strength of an electrode tab can be increased. In addition, the present invention is characterized by comprising: an electrode having a coated portion and a non-coated portion provided along the longitudinal direction of an electrode collector, the coated portion having an active material applied onto the electrode collector, and the non-coated portion having no active material applied onto the electrode collector; and a notching tab portion extending from the coated portion in the transverse direction of the electrode collector such that the active material is not applied thereto, the notching tab portion being formed to overlap in at least two tiers when the electrode is wound.

Description

Secondary Battery and Manufacturing Method of the Secondary Battery

Citation with Related Applications

This application claims the benefit of priority based on Korean Patent Application No. 10-2017-0048645 filed on April 14, 2017 and Korean Patent Application No. 10-2018-0043191 filed on April 13, 2018. All content disclosed in is included as part of this specification.

Field of technology

The present invention relates to a secondary battery and a method for manufacturing the secondary battery, and more particularly, to a secondary battery and a method for manufacturing the secondary battery that can increase the mechanical strength of the electrode tab.

Cells and batteries that generate electric energy through physical or chemical reactions of materials and supply power to the outside cannot obtain AC power supplied to buildings according to the living environment surrounded by various electric and electronic devices. It is used when DC power is needed.

Among such batteries, a primary battery and a secondary battery, which are chemical cells using chemical reactions, are generally used. The primary battery is a consumable battery, commonly referred to as a battery. In addition, the secondary battery is a rechargeable battery manufactured using a material that can be repeated a number of redox process between the current and the material, the power is charged when the reduction reaction to the material by the electric current, the oxidation reaction to the material When performed, the power is discharged. As the charge-discharge is repeatedly performed, electricity is generated.

On the other hand, the lithium ion battery of the secondary battery is coated with a positive active foil and a negative electrode conductive foil in a predetermined thickness, and the separator is interposed between the two conductive foils, so that a plurality of times in a jelly roll or cylindrical form. The electrode assembly produced by winding is housed in a cylindrical or square can, a pouch, or the like, and is manufactured by sealing it.

Korean Unexamined Patent Publication No. 10-2012-0006389 discloses a conventional electrode assembly and a secondary battery including the same.

In order to develop a low resistance cell, a conventional secondary battery needs to apply a metal having a low resistance to a negative electrode tab or increase a number of electrode tabs.

The negative electrode multi-tap structure developed by this necessity was a two-tap structure for attaching electrode tabs to the core and the outer side, or a three-tap structure for attaching the electrode tabs to the core and the outer side and the middle tab to the middle side.

However, in order to attach the middle tab due to the nature of the jelly roll, a non-coating portion should be formed at a predetermined position in the middle of the electrode.

Therefore, the present invention has been made to solve the above problems, the problem of the present invention is to provide a secondary battery and a method for manufacturing the secondary battery that can form a multi-tap while minimizing the unknowing.

In addition, an object of the present invention is to provide a secondary battery and a method for manufacturing the secondary battery that can increase the mechanical strength while forming the electrode tab by notching the electrode foil.

According to an embodiment of the present invention, a secondary battery includes an electrode and a device including a holding part coated with an active material on an electrode current collector and an uncoated part not coated with an active material on the electrode current collector along a length direction of the electrode current collector. It extends so that the active material is not applied from the holding portion in the width direction of the electrode current collector, and when the electrode is wound, it comprises a notching tab portion formed to overlap two or more layers.

The notching tab portion may extend continuously from one third or more of the entire length of the holding portion.

In the state where the electrode is wound, the notching tab part may be cut to form a plurality of notching tabs.

The width of the notching tab may be 4mm ~ 5mm.

The electrode may be accommodated in the can member, and the notching tab may be bent and connected to the can member.

The bent portion formed by bending the notching tab may be joined to the can member.

It may include an insulating member formed between the bent portion and the end of the electrode.

It may include an electrode tab attached to the uncoated portion.

The notching tab part may be notched while the electrode is wound to form a plurality of notching tabs, the electrode may be accommodated in a can member, and the plurality of notching tabs may be bent to overlap the electrode tab.

The electrode tab and the plurality of notching tabs connected to the electrode tab may be bonded to the can member together.

The notching lengths of the plurality of notching tabs may be 8 mm to 11 mm.

The notching lengths of the plurality of notching tabs may be 9 mm to 10 mm.

The electrode may be a cathode.

In the method of manufacturing a secondary battery according to an embodiment of the present invention, a preparing step of preparing an electrode having a holding part coated with an active material on an electrode current collector and an uncoated part not coated with an active material along a length direction of the electrode current collector And a notching tab portion forming step of notching the electrode such that a notching tab portion extending in a state in which the active material is absent in the width direction of the electrode current collector is formed in the electrode in a width direction of at least 1/3 of the length of the holding portion. Winding step of stacking the separator and the other electrode that is upstream with the electrode and then wound to form an electrode assembly, a notching tab forming step of forming the plurality of notching tabs by cutting the notching tab part from the electrode assembly, and the electrode assembly can member It accommodates in and includes an installation step of bonding the notching tab to the can member.

In the preparation step, an electrode of the cathode may be prepared.

In the preparing step, the holding part coated with the active material on the electrode current collector and the non-coating part not coated with the active material may be arranged in parallel with respect to the width direction of the electrode current collector.

In the forming of the notching tab portion, the notching tab portion, in which the active material is not coated in the width direction of the holding portion, may be notched while cutting the holding portion and the uncoated portion arranged in parallel in the longitudinal direction of the electrode current collector.

In the forming of the notching tab portion, the notching tab portion may be notched so that the notching tab portion is not coated with an active material in the width direction of the holding portion while cutting the electrode.

In the forming of the notching tab, the notching tab part may be cut by a laser.

In the installing step, the electrode assembly may be accommodated in a can member while the notching tab is bent to bond a portion bent from the notching tab to the can member.

In the installation step, the bent portion of the notching tab may be joined to the can member by welding.

In the installation step, the bent portions of the plurality of notching tabs may be overlapped with each other and simultaneously bonded to the can member.

The winding step may be formed to overlap the notching tab portion in two or more layers.

According to the present invention, there is an effect of forming a multi-tap while minimizing the formation of the plain portion.

According to the present invention, there is an effect of minimizing electrical resistance by forming a multi-tap.

According to the present invention, there is an effect of minimizing the formation of the uncoated portion to secure battery capacity.

According to the present invention, while forming a notching tab, which is a foil tab, from an electrode foil, the notching tab is overlapped by two or more layers, thereby increasing the mechanical strength.

According to the present invention, the mechanical strength of the notching tab, which is a foil tab, can be strengthened so that the notching tab is not broken in a bent state, so that the notching tab can be joined to the can member in a bent state, thereby ensuring the reliability of electrical connection. It is effective to increase.

According to the present invention, the notching tab and the electrode tab can be joined to the can member at the same time, thereby ensuring the welding processability.

According to the present invention, by forming a plurality of notching tabs on the outer periphery of the electrode assembly, an insulating member can be installed between the plurality of notching tabs and the ends of the electrode assembly, thereby preventing contact between the notching tabs and the electrode assembly to improve safety. It works.

1 is an exploded view showing the electrode in a deployed state according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the state in which FIG. 1 is wound; FIG.

3 is a perspective view illustrating a notching tab formed by cutting the notching tab part in FIG. 2.

4 is a perspective view illustrating the can member in a state in which an electrode assembly according to an embodiment of the present invention is installed in the can member;

FIG. 5 is a bottom view illustrating only the electrode assembly in FIG. 4 from the bottom.

6 is a flowchart sequentially illustrating a method of manufacturing a secondary battery according to an embodiment of the present invention.

FIG. 7 is a plan view illustrating a holding part and an uncoated part formed based on a length direction of an electrode current collector arranged in parallel with respect to a width direction of an electrode current collector, according to an exemplary embodiment.

FIG. 8 is a bottom view of the notch tab and the electrode tab in accordance with another embodiment of the present invention.

FIG. 9 is a side view of FIG. 8 from the side.

Hereinafter, a secondary battery and a method of manufacturing the secondary battery according to a preferred embodiment of the present invention with reference to the accompanying drawings will be described in detail.

The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents.

In the drawings, the size of each component or a specific portion constituting the components is exaggerated, omitted, or schematically illustrated for convenience and clarity of description. Thus, the size of each component does not entirely reflect its actual size. If it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, such description will be omitted.

1 is an exploded view showing the electrode in an unfolded state according to an embodiment of the present invention, Figure 2 is a perspective view showing the wound in FIG.

1 to 2, a secondary battery according to an exemplary embodiment of the present invention includes a holding part 110 coated with an active material a on an electrode current collector and an active material a on the electrode current collector. The uncoated non-coated portion 120 is provided along the longitudinal direction of the electrode current collector and extends from the holding portion 110 to the active material in the width direction of the electrode current collector. When the electrode 100 is wound, it includes a notching tab portion 111 formed to overlap two or more layers. (Notched tab portion 111 overlapped in two layers is illustrated in FIG. 2.)

While forming the notching tab portion, which is a foil tab, from the electrode foil of the electrode current collector, the foil tabs can be stacked in two or more layers, thereby increasing the mechanical strength.

The electrode 100 may be any one of a cathode coated with a cathode active material and a cathode coated with an anode active material. The electrode assembly 1 may be formed by stacking a cathode, a cathode, and a membrane a plurality of times so that a separator is interposed between the cathode and the anode. I can make it.

In addition, the electrode assembly 1 may be manufactured by winding a laminate in which a cathode, a separator, and a cathode are laminated in a jelly roll form.

The positive electrode may be an aluminum electrode current collector, and may include a positive electrode holding part to which the positive electrode active material is coated, and a positive electrode non-coating part to which the positive electrode active material is not coated.

The positive electrode active material may be a lithium-containing transition metal oxide such as LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , LiMnO ₄ , or a lithium chalcogenide compound.

For example, the positive electrode holding part is formed by applying a positive electrode active material to a portion of at least one surface of the aluminum electrode current collector, and the remaining portion of the aluminum electrode current collector without the positive electrode active material may be a positive electrode non-coating portion.

The negative electrode may be a copper electrode current collector, and may include a negative electrode holding portion to which the negative electrode active material is coated and a negative electrode non-coating portion to which the negative electrode active material is not coated.

The negative electrode active material may be crystalline carbon, amorphous carbon, carbon composite, carbon material such as carbon fiber, lithium metal, lithium alloy, or the like.

For example, the negative electrode holding part is formed by applying a negative electrode active material to a portion of at least one surface of the copper electrode current collector, and the remaining portion of the copper electrode current collector to which the negative electrode active material is not coated may be the negative electrode non-coating portion.

The separator is, for example, any one selected from the group consisting of polyethylene (PE), polystyrene (PS), polypropylene (PP), and copolymers of polyethylene (PE) and polypropylene (PP). It can be prepared by coating a polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP co-polymer).

As described above, the electrode 100 of the present invention may be any one or more of a positive electrode and a negative electrode forming the electrode assembly 1, and in particular, may be any one in which a resistance reduction is required in the positive electrode or the negative electrode.

In the present invention, the cathode is described as an embodiment.

The electrode 100 may have a non-coated portion 120 formed at one end thereof, and an electrode tab 121 may be attached to the non-coated portion 120 formed at one end of the electrode 100.

The notching tab part 111 may be formed by notching the electrode 100 to extend in the width direction from the holding part 110 of the electrode 100, and the entire length of the holding part 110 of the electrode 100 is notched. It is formed so that only the electrode current collector is extended in a region corresponding to 1/3 or more of the active material (a) may not be applied.

The notching tab part 111 may be formed by removing only the active material a from the holding part 110 extending from the electrode 100, or the active material a may be formed in the holding part 110 region of the electrode 100. It can also be formed by extending only the electrode foil without being coated.

Therefore, there can be an effect of forming a multi-tap while minimizing the formation of the uncoated portion, and it is possible to secure the battery capacity by minimizing the non-coated portion formation.

As shown in FIG. 3, the notching tabs 111 may be cut in a wound state to form a plurality of notching tabs 111a. As the number of notching tabs 111a increases, the resistance of all the electrode tabs decreases.

At this time, it is preferable that the width of one notching tab 111a is 4mm to 5mm. For this reason, if the width of the notching tab 111a is less than 4mm, the mechanical strength may be weak, and the width of the notching tab 111a may be reduced. This is because if it exceeds 5 mm, deformation may be difficult in the process of bonding for electrical connection with the can member.

Reinforcing the mechanical strength of the notching tab 111a, which is a foil tab, so that the notching tab 111a is not broken in a bent state, so that the notching tab 111a can be joined to the can member in a bent state, thereby providing reliable electrical connection. You can increase the bonding strength while securing.

4 is a perspective view showing the can member in a state in which the electrode assembly according to an embodiment of the present invention is installed in the can member, and FIG. 5 is a bottom view showing only the electrode assembly in FIG.

4 and 5, the electrode assembly 1 according to the secondary battery of the present invention is electrically connected to the can member 10 in a state in which the notching tab 111a is bent while being accommodated in the can member 10. The bent portion of the notching tab 111a may be welded to the can member 10 so as to be connected.

The notching tab 111a is bent so that the end of the notching tab 111a is coupled to the bottom center side of the can member 10 to facilitate electrical connection, and the plurality of notching tabs 111a are electrically connected to minimize electrical resistance. can do.

FIG. 8 is a bottom view of the notching tab and the electrode tab bonded in accordance with another embodiment of the present invention, and FIG. 9 is a side view of FIG.

As shown in FIGS. 8 and 9, in the secondary battery according to another exemplary embodiment of the present invention, the notching tab part 111 is cut from the electrode assembly 1 in which the electrode 100 is wound to form a plurality of notching tabs 111a. And a plurality of notching tabs 111a may be bent and connected to the electrode tab 121 formed at the center portion of the end of the electrode assembly 1.

The electrode assembly 1 is accommodated in the can member 10, and the plurality of notching tabs 111a connected to the electrode tab 121 are joined to the can member 10 together with the electrode tab 121 by welding or the like. Can be.

As described above, the secondary battery according to another embodiment of the present invention secures welding processability because the secondary battery is welded and joined together to the can member 10 in a state where the plurality of notching tabs 111a and the electrode tab 121 are overlapped with each other. Can be easy.

In the secondary battery according to another embodiment of the present invention, when the length of the diameter of the end of the electrode assembly 1 is 16 mm to 21 mm, the notching length of the plurality of notching tabs 111a may be in the range of 8 mm to 11 mm. The reason for this is that if the notching length of the notching tab 111a is less than 8 mm, the length of the notching tab 111a is short and the notching tab 111a is bent to overlap the electrode tab 121 formed at the center portion of the end of the electrode assembly 1. It can be difficult. In addition, if the notching length of the notching tab 111a exceeds 11 mm, the length of the notching tab 111a becomes longer than necessary, thereby increasing the cost due to material waste and the space occupied by the notching tab 111a in the can member 10. The increase in the amount of the electrolyte filled in the can member 10 may cause a decrease in capacity. Preferably, the notching length of the notching tab 111a may be 9 mm to 10 mm.

In the secondary battery according to another exemplary embodiment of the present invention, the insulating member 130 may be formed between the bent portion of the notching tab 111a and the end of the electrode assembly 1 in which the electrode 100 is wound.

The insulating member 130 may insulate between the notching tab 111a and the end of the electrode assembly 1 to prevent contact between the notching tab 111a and the electrode assembly 1.

The plurality of notching tabs 111a may be formed at an outer periphery of the end of the electrode assembly 1 so as not to interfere with the installation of the insulating member 130 at the end of the electrode assembly 1.

A plurality of notching tabs 111a are formed on the outer periphery of the electrode assembly to allow the insulating member 130 to be installed between the plurality of notching tabs 111a and the ends of the electrode assembly 1, thereby notching tabs 111a and the electrodes. Safety can be improved by preventing contact of the assembly 1.

A method of manufacturing a secondary battery according to an embodiment of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 6, the method of manufacturing a secondary battery according to an exemplary embodiment of the present invention includes a preparation step S1, a notching tab part forming step S2, a winding step S3, a notching tap forming step S4, and the like. It includes the installation step (S5).

The preparation step (S1) is an electrode having a holding unit 110 is coated with an active material (a) on the electrode current collector and the non-coating portion 120 is not coated with the active material (a) along the longitudinal direction of the electrode current collector Step 100 is to prepare.

In this case, the electrode 100 may be a cathode.

As shown in FIG. 7, in the preparation step S1, the holding part 110 and the uncoated part 120 formed based on the length direction L of the electrode current collector are referred to the width direction W of the electrode current collector. Can be arranged in parallel.

The notching tab portion forming step S2 may include a notching tab portion 111 extending from the electrode 100 in the width direction W of the holding portion 110 without an active material in a length 1/3 or more of the holding portion 110. Notching the electrode 100 to form a.

As described above, the notching tab portion 111 is notched in the electrode 100 by cutting the electrode 100 in the electrode current collector while the active material a formed in the width direction W of the holding portion 110 is not coated. It may be to form a notching tab portion 11 by notching a part.

In addition, when the holding part 100 and the uncoated part 120 formed based on the longitudinal direction L of the electrode current collector are arranged in parallel with respect to the width direction W of the electrode current collector, the holding parts arranged in parallel. Cutting between the holding portion 110 and the other holding portion 110a arranged in parallel with the width direction W while cutting the 110 and the uncoated portion 120 in the longitudinal direction L of the electrode current collector. The notched tab region not coated with the active material formed thereon may be formed to form the notched tab portion 111 in the width direction W of the holding portion 110.

The winding step S3 may be a step of forming an electrode assembly 1 by laminating the electrode 100 having the notched tab part 111 on the separator and the other electrode that is upper with the electrode 100.

In the process of winding the electrode 100, the notching tabs 111 may be formed to overlap two or more layers.

The notching tab forming step S4 may be a step of forming a plurality of notching tabs 111a by cutting the notching tab portion 111 in the electrode assembly 1.

The notching tabs 111a formed by cutting the notching tabs 111 may form a state of overlapping two or more layers in the same manner as the notching tabs 111.

At this time, the cutting of the notching tab part 111 may maximize the working efficiency by using a laser.

The installation step (S5) is a step of bonding the notching tab 111a to the can member 10 by receiving the electrode assembly 1 in the can member 10.

In the installation step S5, the notching tab 111a is electrically connected to the can member 10, and the notching tab 111a is bent to facilitate welding. May be accommodated in the can member 10.

At this time, since the notching tabs 111a are formed in two or more layers, the mechanical strength can be maintained even when the notching tabs 111a are bent, thereby not easily breaking.

The bent notched tab 111a may have an end portion directed toward the center of the bottom surface of the can member 10.

Coupling the bottom of the can member 10 and the notching tab 111a may allow the bent portion of the notching tab 111a to be welded to the bottom of the can member 10.

In addition, according to another embodiment of the present invention, the bent portion of the plurality of notching tabs 111a are overlapped with each other at the end center side of the electrode assembly 1 in the installation step S5, and the end center portion of the electrode assembly 1 is overlapped with each other. The electrode tab 121 may be joined to the can member 10 at the same time by welding or the like.

As described above with reference to the illustrated secondary battery and a method for manufacturing the secondary battery according to the present invention, the present invention is not limited by the embodiments and drawings described above, the present invention within the claims Various implementations are possible by those skilled in the art.

Claims

An electrode including a holding unit 110 coated with an active material a on an electrode current collector and an uncoated portion 120 on which the active material a is not coated on the electrode current collector along the longitudinal direction of the electrode current collector. 100; And

A notching tab part 111 extending from the holding part 110 in the width direction of the electrode current collector so as not to be coated with the active material and overlapping two or more layers when the electrode 100 is wound; Secondary battery comprising a.
The method according to claim 1,

The notching tab portion 111 is a secondary battery, characterized in that extending continuously from 1/3 or more of the entire length of the holding portion (110).
The method according to claim 1 or 2,

The secondary battery, characterized in that the notching tab portion 111 is cut in a state in which the electrode 100 is wound to form a plurality of notching tabs 111a.
The method according to claim 3,

Secondary battery, characterized in that the width of the notching tab (111a) is 4mm ~ 5mm.
The method according to claim 3,

The electrode 100 is accommodated in the can member 10, the notching tab 111a is bent and the secondary battery, characterized in that connected to the can member (10).
The method according to claim 5,

Secondary battery, characterized in that the bent portion formed by bending the notching tab (111a) is bonded to the can member (10).
The method according to claim 6,

Secondary battery, characterized in that it comprises an insulating member 130 formed between the bent portion and the end of the electrode (100).
The method according to claim 1,

Secondary battery, characterized in that it comprises an electrode tab 121 attached to the uncoated portion (120).
The method according to claim 8,

In the state in which the electrode 100 is wound, the notching tab part 111 is notched to form a plurality of notching tabs 111a.

The electrode 100 is accommodated in the can member 10, the plurality of notching tabs (111a) is bent and the secondary battery, characterized in that connected to overlap the electrode tab 121.
The method according to claim 9,

Secondary battery, characterized in that the plurality of notching tabs (111a) connected to overlap with the electrode tab 121 and the electrode tab 121 is bonded to the can member (10).
The method according to claim 9,

Secondary battery, characterized in that the notching length of the plurality of notching tabs (111a) is 8mm ~ 11mm.
The method according to claim 9,

Secondary battery, characterized in that the notching length of the plurality of notching tabs (111a) is 9mm ~ 10mm.
The method according to claim 1,

The electrode 100 is a secondary battery, characterized in that the negative electrode.
Preparing an electrode 100 having a holding portion 110 coated with the active material (a) and an uncoated portion 120 without the active material (a) coated on the electrode current collector along the longitudinal direction of the electrode current collector. Preparation step (S1);

Notching in which the electrode 100 is notched so that a notching tab portion 111 extending in the width direction of the electrode current collector without the active material is formed in a length 1/3 or more of the holding part 110 in the electrode 100. Tab portion forming step (S2);

A winding step of forming the electrode assembly 1 by stacking the electrode 100 having the notching tab part 111 on the separator and the other electrode that is opposite to the electrode 100 to form an electrode assembly 1;

A notching tab forming step (S4) of cutting the notching tab portion 111 from the electrode assembly 1 to form a plurality of notching tabs 111a; And

An installation step (S5) of accommodating the electrode assembly (1) in the can member (10) to bond the notching tab (111a) to the can member (10); Method of manufacturing a secondary battery comprising a.
The method according to claim 14,

Method of manufacturing a secondary battery, characterized in that for preparing the electrode (100) of the negative electrode in the preparing step (S1).
The method according to claim 14,

The preparation step (S1) is parallel to the holding unit 110, the active material (a) is coated on the electrode collector and the plain portion 120 is not coated on the electrode collector relative to the width direction of the electrode collector. Method for manufacturing a secondary battery, characterized in that arranged in.
The method according to claim 16,

The notching tab portion forming step (S2) may be performed by cutting the holding portion 110 and the uncoated portion 120 arranged in parallel in the longitudinal direction of the electrode current collector, in the width direction of the holding portion 110. ) Is a method of manufacturing a secondary battery, characterized in that notching the notching tab portion (11) is not applied.
The method according to claim 14,

The notching tab portion forming step (S2) may be performed by cutting the electrode 100 such that the notching tab portion 111 without the active material a is applied in the width direction of the holding portion 110 is formed. Method of manufacturing a secondary battery.
The method according to claim 14,

The method of manufacturing a secondary battery, wherein the notching tab forming step (S4) is performed by cutting the notching tab part 111 with a laser.
The method according to claim 14,

In the installation step S5, the electrode assembly 1 is accommodated in the can member 10 while the notching tab 111a is bent, so that the bent portion of the notching tab 111a is bent in the can member 10. The secondary battery manufacturing method characterized by bonding to.
The method of claim 20,

Method of manufacturing a secondary battery, characterized in that the bent portion of the notching tab (111a) is bonded to the can member (10) by welding in the installation step (S5).
The method of claim 20,

Method of manufacturing a secondary battery, characterized in that in the installation step (S5) by overlapping the bent portion of the plurality of notching tabs (111a) and bonded to the can member (10) at the same time.
The method according to claim 14,

The winding step (S3) is a manufacturing method of a secondary battery, characterized in that to form the notching tab portion 111 so as to overlap two or more.