Battery and method for manufacturing a battery

Abstract

The present application provides a battery and a manufacturing method of the battery in which a joint portion of a current collecting tab and a tab lead is not damaged and is sufficiently joined. The battery includes: an electrode group including a positive electrode and a negative electrode; a plurality of current collecting tabs electrically connected to the positive electrode or the negative electrode of the electrode group; and a tab lead joined to the plurality of current collecting tabs, and a joint portion (10) of the current collecting tab and the tab lead has a first joint portion (11) in a straight line shape and a second joint portion (12) in a dotted line shape along a length direction of the current collecting tab and the tab lead.

Description

Technical Field

[0001] This invention relates to batteries and methods for manufacturing batteries. Background Technology

[0002] In recent years, research and development related to secondary batteries that contribute to energy efficiency have been carried out in order to ensure that more people have access to affordable, reliable, sustainable and advanced energy.

[0003] To meet the requirements of high-energy-density secondary batteries, it is necessary to combine multiple current collector contacts into one. As a method for combining multiple current collector contacts into one, a method using an ultrasonic bonding head is known (for example, see Japanese Patent Application Publication No. 2024-019281). This ultrasonic bonding head is capable of ultrasonic vibration in a predetermined vibration direction. The ultrasonic bonding head includes a base portion, a platform portion rising from the upper surface of the base portion, and a pressing portion consisting of multiple protrusions protruding from the upper surface of the platform portion. The multiple protrusions constituting the pressing portion are arranged in a pyramidal or frustum shape, and in plan view, at least a portion of the periphery of the arranged portion of the multiple protrusions is serrated. This serrated portion is formed along at least one of the aforementioned vibration direction and a direction perpendicular to the aforementioned vibration direction. The upper surface of the base portion has an exposed surface where the platform portion is not formed.

[0004] Additionally, a method is known to join multiple current collectors and leads clamped by protection leads using ultrasonic waves in a manner that does not traverse the width end of any current collector that constitutes multiple current collectors. Summary of the Invention

[0005] However, in the conventional methods described above, the increased contact area between the current collectors reduces the contact resistance, which can be expected to improve the performance of the single cell. However, the increased input energy to the very thin current collectors can cause damage to the current collectors that come into contact with the crimping member.

[0006] The purpose of this invention is to provide a battery in which the junction between the current collector and the lead wire is fully engaged without breakage, and a method for manufacturing the battery. This invention contributes to the stabilization of battery performance, improves quality management in the manufacturing process, and consequently contributes to energy efficiency.

[0007] The first aspect of the present invention is a battery, wherein the battery comprises: an electrode group including a positive electrode and a negative electrode; a plurality of current collectors electrically connected to the positive electrode or the negative electrode of the electrode group; and a current collector lead wire engaging with the plurality of current collectors, wherein the engagement portion of the current collectors and the current collector leads has a straight first engagement portion and a dashed second engagement portion along the length direction of the current collectors and the current collector leads.

[0008] In the battery according to the first aspect of the present invention, the joint between the current collector and the lead wire has a straight first joint and a dotted second joint along the length direction of the current collector and the lead wire, so that the joint between the current collector and the lead wire will not be damaged and can be fully joined.

[0009] The second solution, based on the battery involved in the first solution, may also include a first joint portion and a second joint portion disposed along two edges of the first joint portion along its length direction.

[0010] In the battery according to the second aspect of the present invention, the joint has a first joint and a second joint disposed on two edges respectively along the length direction of the first joint, so that the joint between the current collector and the lead wire can be fully joined without damage.

[0011] The third option, based on the battery involved in the second option, may also have two first joints in the joint portion.

[0012] The battery according to the third aspect of the present invention has two first joints, so that the joint between the current collector and the lead wire is not damaged and can be fully joined.

[0013] The fourth embodiment relates to a method for manufacturing a battery, wherein the battery comprises: an electrode group including a positive electrode and a negative electrode; a plurality of current collector contacts electrically connected to the positive electrode or the negative electrode of the electrode group; and contact leads joined to the plurality of current collector contacts. The method for manufacturing the battery comprises the following steps: applying a load and performing ultrasonic vibration by clamping the current collector contacts and the contact leads together from both sides using an ultrasonic bonding tool, thereby ultrasonically bonding the current collector contacts and the contact leads. The ultrasonic bonding tool has a straight first pressing portion and a concave-convex second pressing portion along the length direction of the current collector contacts and the contact leads on the surface in contact with the current collector contacts or the contact leads.

[0014] In the battery manufacturing method according to the fourth aspect of the present invention, the ultrasonic bonding tool has a straight first pressing part and a concave-convex second pressing part on the surface that contacts the current collector and the lead wire along the length direction of the current collector and the lead wire, so that the joint between the current collector and the lead wire will not be damaged and they can be fully bonded.

[0015] The fifth embodiment, based on the battery manufacturing method involved in the fourth embodiment, may also include an ultrasonic bonding tool having a first pressing portion and a second pressing portion disposed on two edges respectively along the length direction of the first pressing portion.

[0016] In the battery manufacturing method according to the fifth aspect of the present invention, the ultrasonic bonding tool has a first pressing part and a second pressing part arranged along the length direction of the first pressing part, so that the bonding part between the current collector and the lead wire is not damaged and can be fully bonded.

[0017] The sixth embodiment, based on the battery manufacturing method involved in the fifth embodiment above, may also include an ultrasonic bonding tool having two of the first pressing portions.

[0018] In the battery manufacturing method according to the sixth aspect of the present invention, two first pressing portions are provided, so that the joint between the current collector and the lead wire is not damaged and can be fully joined.

[0019] According to the present invention, a battery and a method for manufacturing the battery are provided in which the junction of the current collector and the lead wire is fully engaged without breakage. Attached Figure Description

[0020] Figure 1 This is a top view showing the junction of the current collector and the lead wire of the battery according to an embodiment of the present invention.

[0021] Figure 2 This is a top view showing the junction of the current collector and the lead wire of the battery according to an embodiment of the present invention.

[0022] Figure 3 This is a schematic diagram illustrating a battery manufacturing method according to an embodiment of the present invention.

[0023] Figure 4 This is a top view showing the pressing member used in a battery manufacturing method according to an embodiment of the present invention.

[0024] Figure 5 This is a front view showing the first pressing portion of the pressing member used in a battery manufacturing method according to an embodiment of the present invention.

[0025] Figure 6 This is a front view showing the second pressing portion of the pressing member used in a battery manufacturing method according to an embodiment of the present invention.

[0026] Figure 7 This is a top view showing the pressing member used in a battery manufacturing method according to an embodiment of the present invention. Detailed Implementation

[0027] Hereinafter, a battery and a method for manufacturing the battery according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0028] [Battery]

[0029] An embodiment of the present invention relates to a battery comprising: an electrode group including a positive electrode and a negative electrode; a plurality of current collector contacts electrically connected to the positive electrode or the negative electrode of the electrode group; and contact leads engaged with the plurality of current collector contacts, wherein the engagement portion of the current collector contacts and the contact leads has a straight first engagement portion and a dashed second engagement portion along the length direction of the current collector contacts and the contact leads.

[0030] The electrode group may have, for example, a sheet-shaped positive electrode, a sheet-shaped negative electrode, and a separator disposed between the positive and negative electrodes. The positive and negative electrodes are wound or stacked in a spiral shape with the separator in between.

[0031] The positive electrode may have, for example, a current collector made of aluminum foil or aluminum alloy foil, and a positive electrode active material layer formed on one side of the current collector, comprising a positive electrode active material. Examples of positive electrode active materials include oxides, sulfides, and polymers capable of absorbing and releasing lithium. Examples of positive electrode active materials that can achieve high positive electrode potentials include lithium manganese composite oxides, lithium nickel composite oxides, lithium cobalt composite oxides, and lithium iron phosphate.

[0032] The negative electrode may have, for example, a current collector made of copper foil and a layer of negative electrode active material formed on one side of the current collector, which includes the negative electrode active material. Examples of negative electrode active materials include metal oxides, metal sulfides, metal nitrides, and alloys capable of absorbing and releasing lithium. Examples of negative electrode active materials include titanium oxide, lithium titanium oxide, tungsten oxide, amorphous tin oxide, tin silicon oxide, and silicon oxide.

[0033] Examples of membranes include microporous membranes, woven fabrics, nonwoven fabrics, and laminates of the same or different materials. Examples of materials forming the membrane include polyethylene, polypropylene, ethylene-propylene copolymers, and ethylene-butene copolymers.

[0034] A non-aqueous electrolyte is impregnated with the electrode group. The non-aqueous electrolyte is prepared by dissolving an electrolyte (e.g., a lithium salt) in a non-aqueous solvent. Examples of non-aqueous solvents include ethylene carbonate (EC), propylene carbonate (PC), butyl carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (EMC), γ-butyrolactone (γ-BL), sulfolane, acetonitrile, 1,2-dimethoxyethane, 1,3-dimethoxypropane, dimethyl ether, tetrahydrofuran (THF), and 2-methyltetrahydrofuran. One non-aqueous solvent may be used alone, or two or more may be mixed. Examples of electrolytes include lithium perchlorate (LiClO4), lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium hexafluoroarsenate (LiAsF6), and lithium trifluoromethanesulfonate (LiCF3SO3). One electrolyte may be used alone, or two or more may be mixed.

[0035] The positive current collector is electrically connected to multiple parts of the positive electrode and is led out from the electrode group. The negative current collector is electrically connected to multiple parts of the negative electrode and is led out from the electrode group.

[0036] As a positive current collector contact, for example, a positive current collector contact that partially extends from the positive current collector can be used, but it can also be separate from the positive current collector. Similarly, as a negative current collector contact, for example, a negative current collector contact that partially extends from the negative current collector can be used, but it can also be separate from the negative current collector. When it is separate, the current collector contact made of conductive material is electrically connected to the current collector by ultrasonic bonding or the like.

[0037] In the battery of this embodiment, such as Figure 1 As shown, the junction 10 between the current collector and the lead has a straight first junction 11 and a dashed second junction 12 along the length of the current collector and the lead. Preferably, the junction 10 has a first junction 11 and two second junctions 12, 12 arranged along the length of the first junction 11, respectively, at two edges 11a, 11a. This ensures that the junction 10 between the current collector and the lead is fully engaged without causing damage.

[0038] In the battery of this embodiment, such as Figure 2 As shown, in Figure 1 In the structure shown, it is preferable to have two first joints 11. That is, the joint 10 may preferably have two first joints 11, 11 arranged side by side, a second joint 12 arranged along the edge 11a of one of the first joints 11 along its length direction, and a second joint 12 arranged along the edge 11a of the other first joint 11 along its length direction. In this way, the joint 10 between the current collector and the lead can be fully joined without damage.

[0039] According to the battery of this embodiment, the junction 10 of the current collector and the terminal lead has a straight first junction 11 and a dashed second junction 12 along the length direction of the current collector and the terminal lead, so that the junction 10 of the current collector and the terminal lead will not be damaged and can be fully joined.

[0040] [Battery manufacturing method]

[0041] One embodiment of the present invention relates to a method for manufacturing a battery, the battery comprising: an electrode group including a positive electrode and a negative electrode; a plurality of current collector contacts electrically connected to the positive electrode or the negative electrode of the electrode group; and contact leads joined to the plurality of current collector contacts. The method for manufacturing the battery includes the following steps (hereinafter referred to as the "joining step"): applying a load and performing ultrasonic vibration by clamping the current collector contacts and the contact leads together from both sides using an ultrasonic joining tool, thereby ultrasonically joining the current collector contacts and the contact leads. The ultrasonic joining tool has a straight first pressing portion and a concave-convex second pressing portion along the length direction of the current collector contacts and the contact leads on the surface in contact with the current collector contacts or the contact leads.

[0042] In the joining process, such as Figure 3 As shown, while using an ultrasonic bonding tool 100 to clamp and pressurize the structure obtained by overlapping the current collector contact 300 and the contact lead 400 from both sides, an electric current is applied between the ultrasonic bonding tools 100 to bond the current collector contact 300 and the contact lead 400. More specifically, as... Figure 4 As shown, the ultrasonic bonding tool 100 has a pressing member 200 on the surface that contacts the current collector contact 300 or the contact lead 400. The pressing member 200 has a [specific feature] along the length direction of the current collector contact 300 and the contact lead 400 on the surface that contacts the current collector contact 300 or the contact lead 400. Figure 4 and Figure 5 The linear first pressing part 201 shown, and Figure 4 and Figure 6 The second pressing portion 202 has a concave-convex shape as shown. The pressing member 200 may preferably have a first pressing portion 201 and second pressing portions 202, 202 arranged along two edges 201a, 201a of the first pressing portion 201, respectively.

[0043] In the battery of this embodiment, it is preferable to have the following: Figure 7 As shown Figure 4The structure shown has two first pressing portions 201. That is, the pressing member 200 can preferably have two first pressing portions 201, 201 arranged side by side, a second pressing portion 202 arranged along the edge 201a of one of the first pressing portions 201 in the length direction, and a second pressing portion 202 arranged along the edge 201a of the other first pressing portion 201 in the length direction. As a result, the joint between the current collector 300 and the contact lead 400 can be fully engaged without damage.

[0044] According to the battery manufacturing method of this embodiment, the pressing member 200 of the ultrasonic bonding tool 100 has a straight first pressing portion 201 and a concave-convex second pressing portion 202 along the length direction of the current collector contact 300 and the contact lead 400 on the surface that contacts the current collector contact 300 or the contact lead 400. Therefore, the joint between the current collector contact 300 and the contact lead 400 will not be damaged and they can be fully bonded.

[0045] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the above embodiments. Various modifications and alterations can be made within the scope of the spirit of the present invention as described in the technical solution.

Claims

1. A battery, wherein, The battery has the following features: Electrode group, which includes positive and negative electrodes; Multiple current collectors are electrically connected to the positive or negative electrode of the electrode group; and The contact lead is connected to the plurality of current collector contacts. The junction of the current collector and the lead wire has a straight first junction and a dashed second junction along the length of the current collector and the lead wire.

2. The battery according to claim 1, wherein, The joint has a first joint and a second joint disposed along two edges of the first joint.

3. The battery according to claim 2, wherein, The joint has two first joints.

4. A method for manufacturing a battery, wherein, The battery has the following features: Electrode group, which includes positive and negative electrodes; Multiple current collectors are electrically connected to the positive or negative electrode of the electrode group; and The contact lead is connected to the plurality of current collector contacts. The battery manufacturing method includes the following steps: An ultrasonic bonding tool is used to clamp the current collector and the lead wire from both sides, thereby applying a load and subjecting the structure to ultrasonic vibration to ultrasonically bond the current collector and the lead wire. The ultrasonic bonding tool has a straight first pressing portion and a concave-convex second pressing portion along the length direction of the current collector and the lead wire on the surface that is in contact with the current collector or the lead wire.

5. The method for manufacturing a battery according to claim 4, wherein, The ultrasonic bonding tool has a first pressing portion and a second pressing portion arranged along two edges of the first pressing portion along its length.

6. The method for manufacturing a battery according to claim 5, wherein, The ultrasonic bonding tool has two of the first pressing parts.

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