KR20230000343A - Electric energy storage device comprising electrode lead in rivet structure - Google Patents

Abstract

The present invention relates to an electric energy storage device comprising an electrode lead coupled with a rivet structure. More specifically, the present invention relates to an electric energy storage device comprising an electrode lead coupled with a rivet structure. The electric energy storage device comprising an electrode lead coupled with a rivet structure includes: a sheet consisting of a positive electrode, a negative electrode, and a separator; a positive electrode terminal connected to the positive electrode of the sheet and formed on one side; a negative electrode terminal connected to the negative electrode of the sheet and formed on the other side; internal electrode leads connected to the positive electrode terminal or the negative electrode terminal, and bonded to upper and lower surfaces of the sheet; pouch films stacked on upper and lower surfaces of the internal electrode leads and coupled to each other to form an electric energy storage device; external electrode leads bonded to both upper and lower surfaces of the pouch films and transmitting electricity generated by the sheet to the outside; and a rivet coupled through holes provided in the internal electrode leads, pouch films, and external electrode leads, wherein the external electrode lead includes a connection part for connecting the external electrode leads so that the adjacent electric energy storage device is connected and fixed. According to the present invention, the rivet can be protected through the connection part.

Description

Electric energy storage device comprising electrode lead in rivet structure

The present invention relates to an electrical energy storage device including electrode leads coupled in a rivet structure, and more particularly, an electrical energy storage device capable of being laminated at a low pressure by combining an internal electrode lead, an external electrode lead, and a pouch film in a rivet structure. The present invention relates to an electrical energy storage device including electrode leads coupled in a rivet structure capable of reducing contact resistance and connecting and fixing the electrical energy storage device through a connection portion provided in an external electrode lead.

In general, an energy storage device refers to a device that stores electrical energy inside and supplies it to the outside when necessary. Among energy storage devices, electrical energy storage devices using electrochemical reactions typically include batteries and capacitors.

Here, the battery generates electricity through the oxidation-reduction reaction of lithium ion in the case of a lithium ion battery and can charge and discharge power slowly for a long time, and a capacitor has high power density but low energy density and can output high power at once. However, the charging/discharging time is very fast.

On the other hand, supercapacitors are located in the middle of conventional capacitors and batteries, and can store a large amount of energy compared to conventional capacitors while generating a much higher output than batteries. A supercapacitor is an energy storage device that stores a lot of energy by using simple ion movement between electrode and electrolyte interface or charging phenomenon by surface chemical reaction and then emits high energy for tens of seconds to minutes. It is also called an ultra capacitor. do.

The electric energy storage device as described above is mainly cylindrical, coin-shaped, or pouch-shaped. Here, the pouch-type electrical energy storage device has a structure in which an electrode assembly capable of charging and discharging is sealed inside an exterior material, and an electrode lead electrically connected to the electrode assembly protrudes from the exterior material to transmit current.

Here, when the electrical energy storage device has an internal electrode lead, a pressurization process is required when stacking the electrical energy storage device due to a step difference between the exterior material and the internal electrode lead. Since the pressure process may cause damage to electrode leads, a technique for stacking electric energy storage devices even at low pressure is required.

As the prior art, Korean Patent Publication No. 10-2018-0104953 "pouch-type secondary battery" is described. The technology includes an electrode assembly in which an anode, a separator, and a cathode are alternately stacked, and each electrode has a lead protruding outward; and a pouch case having an accommodating portion capable of accommodating the electrode assembly, wherein a lead protrusion direction of the positive electrode and a lead protrusion direction of the negative electrode form a right angle to each other, suggesting a pouch-type secondary battery. .

Such a technique has a problem in that the pressurization process cannot be performed at a low pressure, the contact force of the electric energy storage device is low, and the surface deviation is large.

Therefore, the present invention has been proposed to improve such conventional problems, and more specifically, an electrical energy storage device can be laminated at a low pressure by combining an internal electrode lead, an external electrode lead, and a pouch film in a rivet method, and contact An object of the present invention is to provide an electrical energy storage device including electrode leads coupled in a rivet structure capable of lowering resistance and connecting and fixing the electrical energy storage device through a connection portion provided in an external electrode lead.

In order to solve the above problems, an electric energy storage device including electrode leads coupled in a rivet structure according to a first embodiment of the present invention includes a sheet composed of an anode, a cathode, and a separator; a positive electrode terminal connected to the positive electrode of the sheet and formed on one side; a negative electrode terminal connected to the negative electrode of the sheet and formed on the other side; Internal electrode leads connected to the positive terminal and the negative terminal, respectively, and located on the upper and lower surfaces of the sheet; a pouch film installed in contact with the internal electrode leads and coupled to each other to form an electrical energy storage device; Includes an external electrode lead bonded to both upper and lower surfaces of the electrical energy storage device to transmit electricity generated in the sheet to the outside, and a rivet coupled through a hole provided in the internal electrode lead, pouch film, and external electrode lead The external electrode leads may include a connecting portion for connecting the external electrode leads to connect and fix an electrical energy storage device positioned adjacent thereto.

In addition, the rivet includes a head and a body, and the body protrudes to the outside of the external electrode lead after being coupled to serve as a protrusion of the electric energy storage device.

In addition, the connection part is formed in plurality on one surface of the external electrode lead, and includes a fitting member formed adjacent to the rivet and a mounting member formed on the other surface of the external electrode lead to insert the fitting member into a pair. It may include an electrode lead coupled with a rivet structure including.

In addition, in the electric energy storage device including the electrode leads coupled in a rivet structure according to the second embodiment of the present invention, the body of the rivet is divided into a plurality of parts at the bottom, but is formed to open at an acute angle in the center, so that the pressurization process with low pressure It may include a tail to enable this.

In addition, the outer side of the lower end of the tail portion is formed in a curved shape, so that the external electrode lead can be prevented from being damaged during coupling.

In addition, in the electric energy storage device including the electrode leads coupled in a rivet structure according to the third embodiment of the present invention, the head of the rivet is formed across the circumference at the lower end and contacts the internal electrode lead to change the rivet connection position when pressurized. It may include a fixing protrusion to prevent shaking.

A rivet of an electric energy storage device including electrode leads coupled in a rivet structure according to a fourth embodiment of the present invention includes an external rivet exposed to the outside of the external electrode lead and an internal rivet coupled to the external rivet, The external rivet includes an external rivet head contacting an outer surface of the external electrode lead and an external rivet shaft formed in a tubular shape and coupled to the internal rivet, wherein the internal rivet is buried inside through a hole of the internal electrode lead. It may include an inner rivet head and an inner rivet shaft formed to have a length at a lower end of the inner rivet head and inserted into and coupled to the outer rivet shaft.

According to an embodiment of the present invention, an electrical energy storage device including electrode leads coupled in a rivet structure can laminate an electrical energy storage device at low pressure by combining an internal electrode lead, an external electrode lead, and a pouch film in a rivet method. .

In addition, as the pressure of the pressing process is increased, the contact resistance may be lowered.

In addition, it is possible to laminate the electrical energy storage device as well as protect the rivet through the connection.

In addition, the body of the rivet serves as a protrusion of the electrical energy storage device to increase the contact surface between the electrical energy storage devices.

In addition, rivets can be coupled with low pressure through the tail.

In addition, the riveting position can be fixed through the fixing protrusion.

In addition, the thickness of the electric energy storage device can be reduced by embedding the internal rivet head into the internal electrode lead.

In addition, the effects according to the embodiments of the present invention mentioned above are not limited to the described content, and may further include all effects predictable from the specification and drawings.

1 is a perspective view showing an electrical energy storage device including electrode leads coupled in a rivet structure according to a first embodiment of the present invention, except for a connection part;
Figure 2 is a perspective view showing the appearance of the sheet, positive electrode terminal and negative terminal of Figure 1;
3 is a cross-sectional view taken along line A-A' of FIG. 1;
4(a) and (b) are a perspective view and a bottom perspective view illustrating an electric energy storage device including electrode leads coupled in a rivet structure according to a first embodiment of the present invention.
5(a) and (b) are side views illustrating the electrical energy storage device of FIG. 4 before and after being stacked.
FIG. 6(a) is a perspective view showing an electric energy storage device including electrode leads coupled in a rivet structure according to a second embodiment of the present invention before rivets are coupled, and FIG. 6(b) is A perspective view showing the appearance after the rivets are joined.
Figure 7 (a) is a cross-sectional view taken along line BB' of Figure 6 (a), Figure 7 (b) is a cross-sectional view taken along line C-C' of Figure 6 (b).
8 is a perspective view illustrating a lower surface of an electric energy storage device including electrode leads coupled in a rivet structure according to a third embodiment of the present invention.
9 is an exploded perspective view of FIG. 8;
Figures 10 (a) to (c) are exemplary views showing the process of coupling rivets through a cross section along the line D-D' of FIG.
11 is a cross-sectional view of an electrical energy storage device including electrode leads coupled in a rivet structure according to a fourth embodiment of the present invention.
12 (a) to (c) are exemplary diagrams illustrating a process in which the rivets of FIG. 11 are combined.

Hereinafter, the description of the present invention with reference to the drawings is not limited to specific embodiments, and various transformations may be applied and various embodiments may be applied. In addition, the content described below should be understood to include all conversions, equivalents, or substitutes included in the spirit and scope of the present invention.

In the following description, terms such as first and second are terms used to describe various components, and are not limited in meaning per se, and are used only for the purpose of distinguishing one component from another.

Like reference numbers used throughout this specification indicate like elements.

Singular expressions used in the present invention include plural expressions unless the context clearly dictates otherwise. In addition, terms such as "include", "include" or "have" described below are intended to designate that features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist. should be construed, and understood not to preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

Prior to describing the present invention, the electrical energy storage device described in the present invention may be configured in various shapes that are not limited to, such as a prismatic shape, a pouch shape, and a cylindrical shape.

In addition, the electrical energy storage device may use various electrical energy storage cells capable of storing electrical energy, such as supercapacitor cells, lithium ion battery cells, and lithium ion capacitor cells, but in the present invention, pouch-type battery cells formed in the form of pouches will be explained based on

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 12 attached. In addition, FIGS. 6 to 12 are shown excluding connection parts in order to more clearly show the configuration of the embodiment.

1 is a perspective view showing an electrical energy storage device including electrode leads coupled by a rivet structure according to a first embodiment of the present invention, excluding connection parts, and FIG. 2 is a sheet, positive terminal, and negative terminal of FIG. 1 It is a perspective view showing the appearance of, Figure 3 is a cross-sectional view taken along line A-A 'of Figure 1, Figure 4 (a) and (b) are electrodes coupled by a rivet structure according to the first embodiment of the present invention It is a perspective view and a bottom perspective view showing an electric energy storage device including a lead, and FIGS. 5 (a) and (b) are side views showing the electric energy storage device of FIG. 4 before and after being laminated. .

1 to 3, the electrical energy storage device 1 including the electrode leads combined in the rivet structure of the present invention largely includes a sheet 10, a positive terminal 20, a negative terminal 30, and an internal electrode. It may include a lead 40, a pouch film 50, and an external electrode lead 60.

First, the sheet 10 is composed of an anode, a cathode, and a separator, and may be formed of a sheet 10 commonly used in the art to which the present invention belongs. The shape of the sheet 10 may be formed in a stack type, a jelly roll type, a stack and folding type, or a Z-folding type, It is not limited to this. It is not limited to this.

A positive electrode is a positive electrode current collector coated with a positive electrode active material, and a negative electrode is a negative electrode active material coated. The positive electrode current collector and the negative electrode current collector may generally have a thickness of 3 to 500 μm.

The separation membrane is not particularly limited as long as it is commonly used in the technical field to which the present invention belongs. For example, a multilayer film formed of PE, PP, or a combination thereof having a microporous structure, or a polymer film for a solid polymer electrolyte or a gel polymer electrolyte may be used.

The positive terminal 20 may be connected to the positive electrode of the sheet 10 and protrude on one side, and the negative electrode terminal 30 may be connected to the negative electrode of the sheet 10 and protrude on the other side.

The internal electrode lead 40 is formed in the form of a thin plate, connected to the positive terminal 20 and the negative terminal 30, respectively, and may be positioned on both upper and lower surfaces of the sheet 10. At this time, the internal electrode lead 40 connected to the positive terminal 20 has a positive electrode, and the internal electrode lead 40 connected to the negative terminal 30 has a negative electrode.

Specifically, when the internal electrode lead 40 connected to the positive terminal 20 is located on the upper surface of the sheet 10, the internal electrode lead 40 connected to the negative terminal 30 is located on the lower surface of the sheet 10 can do. In addition, the internal electrode lead 40 may be joined to the positive terminal 20 or the negative terminal 30 by welding such as ultrasonic welding, but is not limited thereto.

The pouch film 50 may be installed in contact with the internal electrode lead 40 and coupled to each other to form the electrical energy storage device 1 .

The material of the pouch film 50 is not particularly limited as long as it is commonly used in the technical field to which the present invention belongs. The pouch film 50 may be composed of a laminated multi-layer structure, a resin inner layer serving as a heat sealing layer, a substrate maintaining mechanical strength, a metal foil layer serving as a moisture and oxygen barrier layer, and a substrate and protective layer. External layers serving as may be sequentially laminated.

The external electrode leads 60 are bonded to both upper and lower surfaces of the electrical energy storage device 1, and can transmit electricity generated in the sheet 10 to the outside. Here, the outside may be an electronic device that is driven by receiving electricity or may be another electrical energy storage device (1).

In addition, the external electrode lead 60 is formed in a form exposed to the outside in order to electrically connect with the inner sheet 10, and an insulating film for protecting the external electrode lead 60 may be attached to the upper and lower surfaces.

Finally, the rivet 70 can penetrate through the holes provided in the internal electrode lead 40, the pouch film 50, and the external electrode lead 60, and for this purpose, the head portion 71 and the body 72 can include

Hereinafter, the direction of the rivet 70 toward the upper surface of the head 71 is referred to as 'upward', and the opposite direction is referred to as 'downward'.

In general, a rivet is a rod-shaped connecting material used to permanently join metal materials, and metal materials with holes are overlapped, rivets are inserted by matching holes, and the heads are supported and fastened by beating with a machine.

Through the combination of these rivets 70, the electrical energy storage device 1 can combine the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 with a low pressure, and the pressure is further increased to Contact resistance between the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 may be reduced.

The head portion 71 is formed to have a larger diameter than the hole provided in the internal electrode lead 40 and can contact the outer surface of the internal electrode lead 40 . The shape of the head 71 can be formed in a round shape, a flat shape, a round dish shape, a pot shape, a thin flat shape, etc., but is not limited thereto.

The body 72 is formed on the lower side of the head 71 and may be formed to have a length in a vertical direction. The lower end of the body 72 may be deformed in a horizontal direction by a pressing process and coupled thereto.

In addition, the body 72 may protrude to the outside of the external electrode lead 60 after being coupled to serve as a protrusion of the electrical energy storage device 1 . It is preferable that the height of the body 72 protruding from the external electrode lead 60 protrudes from the external electrode lead 60 in a range of 100 μm to 5 mm. In this case, when the height of the protruding body 72 is less than 100 μm, the contact effect between the electric energy storage devices 1 may be insignificant, and when the height exceeds 5 mm, electricity transmission efficiency may be reduced.

The material of the rivet 70 may allow current to flow normally by using the same material as the internal electrode lead 40 and the external electrode lead 60 . However, it is not limited thereto and can be used in various ways as a heat-resistant material capable of withstanding heat generated and transmitted from the inside and as a conductive material capable of transmitting current.

For example, when the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 are combined in a state in which holes are provided only in the internal electrode lead 40 and the pouch film 50, the external electrode lead ( 60) can be rolled inside during the rivet 70 coupling process. Accordingly, current transfer efficiency may be increased.

Also. Holes provided in the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 are the diameter of the body 72 increases when the rivet 70 is coupled, so that the body 72 of the rivet 70 It is preferable to form slightly larger than the diameter. However, it is not limited thereto.

For example, the body of the rivet 70 is formed to have the same diameter as the diameter of the hole provided in the internal electrode lead 40, the pouch film 50, and the external electrode lead 60, so that the internal electrode lead 40, the pouch film (50) and an external electrode lead (60).

Referring to FIGS. 4 and 5 , the external electrode lead 60 may include a connection portion 61 to be connected to the external electrode lead 60 of another electrical energy storage device 1 .

The connecting portion 61 is capable of connecting the external electrode leads 60 so as to connect and fix the adjacent electric energy storage device 1, and may include a fitting member 610 and a mounting member 611. there is.

The fitting member 610 is formed on the external electrode lead 60 on one side of the electrical energy storage device 1 and may be formed adjacent to the rivet 70 . The fitting member 610 may be spaced apart from the position of the rivet 70 formed on the external electrode lead 60 at a predetermined interval and arranged in a line along the position of the rivet 70 .

In addition, the fitting member 610 is formed at both ends of the external electrode lead 60 so that the electrical energy storage device 1 can be stably stacked when combined with the seating member 611 . However, it is not limited thereto and may be formed in various positions such as the center and the side.

The seating member 611 may be formed on the external electrode lead 60 on the other surface of the electrical energy storage device 1 and formed in a pair so that the fitting member 610 is inserted therein. The seating member 611 is formed at a position corresponding to the fitting member 610 and secures a space having the same shape as the fitting member 610 so that the fitting member 610 can be inserted.

In addition, the fitting member 610 and the mounting member 611 are preferably formed at a height at which the rivets 70 can come into contact with each other when the electrical energy storage device 1 is stacked, but is not limited thereto.

Specifically, as shown in (a) of FIG. 4, the rivet 70 is formed to protrude from the external electrode lead 60, and the fitting member 610 is formed on the upper surface of the external electrode lead 60 by rivet 70. and can be formed adjacent to. Meanwhile, as shown in (b) of FIG. 4 , the seating member 611 may be formed on the upper surface of the external electrode lead 60 at a position corresponding to the fitting member 610 .

As such, when the electrical energy storage device 1 is stacked on the adjacent electrical energy storage device 1, the connection portion 61 connects the two electrical energy storage devices 1 through the combination of the fitting member 610 and the seating member 611. It can increase the stability of the liver.

Specifically, as shown in (a) of FIG. 5, an external electrode lead 60 having a fitting member 610 is formed on the upper surface of the electrical energy storage device 1, and the electrical energy storage device 1 An external electrode lead 60 provided with a pair of seating members 611 may be formed on the lower surface of the .

When a plurality of electrical energy storage devices 1 formed as described above are provided and stacked, as shown in FIG. 5(b), the lower surface of one electrical energy storage device 1 and the other electrical energy storage device The fitting member 610 may be inserted into the seating member 611 while the upper surfaces of (1) meet. Electrical energy storage devices 1 can be connected to this.

In addition, the connection part 61 can not only stack the electric energy storage device 1 only by combining the fitting member 610 and the seating member 611, but also increase the contact area between the rivets 70.

FIG. 6(a) is a perspective view showing an electric energy storage device including electrode leads coupled in a rivet structure according to a second embodiment of the present invention before rivets are coupled, and FIG. 6(b) is It is a perspective view showing a state after rivets are coupled, and FIG. 7 (a) is a cross-sectional view taken along line BB 'of FIG. 6 (a), and FIG. 7 (b) is FIG. 6 (b) It is a cross-sectional view along line C-C'.

Referring to FIGS. 6 and 7 , the electrical energy storage device 1 including electrode leads coupled in a rivet structure according to the second embodiment of the present invention has a tail portion 720 attached to a body 71 of a rivet 70. ) may be included.

Here, except for the tail portion 720, the electrical energy storage device 1 including the electrode leads coupled in the rivet structure according to the second embodiment of the present invention according to the first embodiment of the present invention described above It can be said that it is substantially the same as the electrical energy storage device 1 including the electrode leads joined in a rivet structure.

Therefore, only the tail portion 720 will be described in detail.

The tail portion 720 is formed such that one end of the body 72 is divided into a plurality of pieces, and is formed to open at an acute angle from the center so that a pressurization process can be performed at a low pressure. The tail portion 720 may be formed by being divided from a point spaced apart from the body 72 on the side of the head portion 71 by a predetermined interval.

At this time, the tail portion 720 can be compressed to the undivided body 72 by the pressing process, and the height of the body 72 excluding the tail portion 720 is the internal electrode lead 40 and the pouch film 50 and a height at which the external electrode lead 60 is bonded. However, it is not limited thereto.

In addition, the height of the rivet 70 may vary depending on the degree of pressing, and may be slightly smaller than the height of the body 72 excluding the tail portion 720 after the pressing process, but is not limited thereto.

In addition, the point where the tail portion 720 is formed in the body 72 may be determined according to the user's request, and accordingly, the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 are bonded. The height can be adjusted.

In addition, the outer side of the lower end of the tail portion 720 is formed in a curved shape, so that the external electrode lead 60 can be prevented from being damaged during coupling. The outer side of the lower end of the tail portion 720 is a portion in contact with the external electrode lead 60, and if formed at a right angle, the surface of the external electrode lead 60 may be damaged. Accordingly, by curving the outside of the lower end of the tail portion 720, not only surface damage of the external electrode lead 60 by the tail portion 720 is prevented, but also corrosion caused by the surface damage can be prevented.

Specifically, referring to FIGS. 6(a) and 7(a), the tail portion 720 protrudes from the external electrode lead 60 and is pushed outward with respect to the center of the body 72 by pressure. The tail portion 720 may be bent. Then, as shown in (b) of FIG. 6 and (b) of FIG. 7 , the tail portion 720 is compressed while bending outward from the divided point, and thus the tail portion 720 attaches to the external electrode lead 60. can be contacted and bonded.

At this time, the surface of the external electrode lead 60 comes into contact with the curved shape of the tail portion 720 so that the external electrode lead 60 can be combined while preventing surface damage.

In addition, the tail portion 720 may increase the contact force between the rivets 70 when the electrical energy storage device 1 is stacked by forming protrusions after coupling according to the number of divisions. For example, as shown in FIG. 6 , if the tail portion 720 is divided into four parts, four protrusions per rivet 70 may be formed in the electric energy storage device 1 after the rivet 70 is coupled. there is.

8 is a perspective view showing a lower surface of an electric energy storage device including electrode leads coupled by a rivet structure according to a third embodiment of the present invention, FIG. 9 is an exploded perspective view of FIG. 8, and FIG. 10 ( A) to (c) are exemplary diagrams illustrating a process of coupling rivets through a cross section along line D-D' in FIG. 8 .

8 to 10, the electric energy storage device 1 including electrode leads coupled in a rivet structure according to the third embodiment of the present invention has a fixing protrusion ( 710) may be included.

Here, except for the fixing protrusion 710, the electric energy storage device 1 including the electrode leads coupled in the rivet structure according to the third embodiment of the present invention according to the first embodiment of the present invention described above It can be said that it is substantially the same as the electrical energy storage device 1 including the electrode leads joined in a rivet structure.

Therefore, only the fixing protrusion 710 will be described in detail.

The fixing protrusions 710 protrude downward from the lower end of the head 71 of the rivet 70, and may be formed in plurality to contact the outer surface of the internal electrode lead 40.

In addition, the internal electrode lead 40 may be provided with a fixing groove 42 at a position corresponding to the fixing protrusion 710 to increase the fixing and coupling force between the fixing protrusion 710 and the internal electrode lead 40 .

Accordingly, the rivet 70 penetrates through the holes provided in the internal electrode lead 40, the pouch film 50, and the external electrode lead 60, and the fixing protrusion 710 of the rivet 70 is attached to the internal electrode lead 40. ) Can be inserted into the fixing groove 42 and fixed.

Specifically, referring to FIG. 9, the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 are placed in order, and the inner hole 41, which is a hole provided respectively, the pouch hole 51 and It can be positioned according to the outer hole 62. In addition, when the number of fixing protrusions 710 on the head 71 is formed, four fixing grooves 42 may be formed on the outer surface of the internal electrode lead 40 to correspond to the fixing protrusions 710 . Accordingly, the body 72 of the rivet 70 may be positioned to coincide with the centers of the inner hole 41, the pouch hole 51 and the outer hole 62, and the fixing protrusion 710 of the head 71 is It may be positioned to correspond to the fixing groove 42 of the internal electrode lead 40.

Accordingly, as shown in (a) of FIG. 10, the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 are provided in the inner hole 41, the pouch hole 51, and the outer hole 62. can be stacked to fit. Then, as shown in (b) of FIG. 10, the body 72 of the rivet 70 penetrates the inner hole 41, the pouch hole 51 and the outer hole 62, and the fixing protrusion of the head 71 (710) can be inserted into the fixing groove (42). Finally, the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 may be coupled by the rivet 70 as shown in (c) of FIG. 10 through a pressing process.

At this time, since the rivet 70 is fixed to the internal electrode lead 40 by the fixing protrusion 710, the coupling position of the rivet 70 may not be shaken when pressurized. This is to prevent the contact force between the rivets 70 from being lowered due to a change in the position of the rivets 70 during the pressing process.

11 is a cross-sectional view of an electrical energy storage device including electrode leads coupled by a rivet structure according to a fourth embodiment of the present invention, and FIGS. 12 (a) to (c) show the process of coupling the rivets of FIG. 11 It is an example shown.

11 and 12, the rivet 70 of the electric energy storage device 1 including the electrode leads coupled in a rivet structure according to the fourth embodiment of the present invention includes an external rivet 73 and an internal rivet ( 74) may be included.

Here, except for the rivet 70, the electric energy storage device 1 including the electrode leads coupled in the rivet structure according to the fourth embodiment of the present invention has the rivet according to the first embodiment of the present invention described above. It can be said that it is substantially the same as the electrical energy storage device 1 including electrode leads combined in a structure.

Therefore, only the rivet 70 will be described in detail.

First, the external rivet 73 is exposed to the outside of the external electrode lead 60 and may include an external rivet head 730 and an external rivet shaft 731 .

The external rivet head 730 may contact the outer surface of the external electrode lead 60 to fix the internal electrode lead 40, the pouch film 50, and the external electrode lead 60.

The external rivet shaft 731 is formed to have a length from the external rivet head 730, and may be formed in a tubular shape having a length inward.

The internal rivet 74 may be combined with the external rivet 73 to bond the internal electrode lead 40 , the pouch film 50 and the external electrode lead 60 . To this end, the internal rivet 74 may include an internal rivet head 740 and an internal rivet shaft 741 .

The internal rivet head 740 may be buried inside through the internal hole 41 of the internal electrode lead 40 . The inner rivet head 740 may be formed in the same shape as the inner hole 41 and coupled thereto. For example, the inner hole 41 is formed in a shape that narrows in diameter toward the pouch film 50, and the inner rivet head 740 is formed in a shape that narrows toward the lower side so that it is inserted and buried even at low pressure when pressurized. It is desirable to do However, it is not limited thereto.

In addition, the surface of the internal rivet head 740 may be formed flat to be flush with the internal electrode lead 40 after being embedded in the internal electrode lead 40 .

At this time, as shown in FIG. 11, the internal rivet head 740 is embedded in the internal electrode lead 40 so that a step between the internal electrode lead 40 and the sheet 10 inside the electric energy storage device 1 does not occur. may not be Accordingly, the thickness of the electrical energy storage device 1 can be reduced, and the total stacking volume can be reduced when a plurality of electrical energy storage devices 1 are stacked.

The inner rivet shaft 741 is formed to have a length from the inner rivet head 740, but is smaller than the inner circumferential diameter of the outer rivet shaft 731 and can be inserted into the outer rivet shaft 731.

Specifically, as shown in (a) of FIG. 12, the inner electrode lead 40, the pouch film 50, and the outer electrode lead 60 are provided in the inner hole 41, the pouch hole 51, and the outer hole 62. can be stacked to fit. Then, as shown in (b) of FIG. 12, the external rivet head 730 of the external rivet 73 contacts the external electrode lead 60, and the external rivet shaft 731 forms an internal hole 41, a pouch hole ( 51) and may be inserted through the outer hole 62. Finally, as shown in (c) of FIG. 12, the inner rivet shaft 741 is inserted into the outer rivet shaft 731 and the inner rivet head 740 is pressed while being inserted into the inner hole 41 of the inner electrode lead 40. Through the process, the internal electrode lead 40, the pouch film 50, and the external electrode lead 60 may be combined.

At this time, the surface of the internal electrode lead 40 may be flat without protruding parts even after the rivet 70 is coupled, and may contact the sheet 10 inside the electric energy storage device 1 without a step.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art can implement them in other specific forms without changing the technical spirit or essential features of the present invention. you will be able to understand In addition, elements of the embodiments of the present invention may be combined, combined, or substituted with each other. Therefore, the embodiments described above are illustrative in all respects and are not restrictive.

1: Electrical energy storage device
10: sheet
20: positive terminal
30: negative terminal
40: internal electrode lead
41: inner hole
42: fixed groove
50: pouch film
51: pouch hole
60: external electrode lead
61: connection part
610: fitting member
611: seating member
62: outer hole
70 : rivet
71: head
710: fixed protrusion
72: body
720: tail
73: external rivet
730: external rivet head
731: external rivet shaft
74: internal rivet
740: internal rivet head
741: internal rivet shaft

Claims (7)

A sheet composed of an anode, a cathode and a separator;
a positive electrode terminal connected to the positive electrode of the sheet and formed on one side;
a negative electrode terminal connected to the negative electrode of the sheet and formed on the other side;
Internal electrode leads connected to the positive terminal and the negative terminal, respectively, and located on the upper and lower surfaces of the sheet;
a pouch film installed in contact with the internal electrode leads and coupled to each other to form an electrical energy storage device;
External electrode leads bonded to both upper and lower surfaces of the electrical energy storage device to transmit electricity generated in the sheet to the outside; and
A rivet coupled through holes provided in the inner electrode lead, the pouch film, and the outer electrode lead,
The external electrode lead,
An electrical energy storage device comprising electrode leads coupled in a rivet structure including a connecting portion for connecting and fixing adjacent electrical energy storage devices to the external electrode leads.
According to claim 1,
The rivet,
including the head and body,
the body,
An electrical energy storage device including an electrode lead coupled in a rivet structure, characterized in that after coupling, it protrudes to the outside of the external electrode lead and serves as a protrusion of the electrical energy storage device.
According to claim 1,
The connection part,
A fitting member formed on an external electrode lead on one side of the electrical energy storage device and adjacent to the rivet; and
An electrical energy storage device comprising an electrode lead formed on an external electrode lead on the other surface of the electrical energy storage device and coupled with a mounting member in a rivet structure so that the fitting member is inserted.
According to claim 2,
The body of the rivet,
An electrical energy storage device comprising electrode leads that are divided into a plurality of ends and are joined in a rivet structure including a tail portion that is formed to open at an acute angle in the center to enable a pressurization process at a low pressure.
According to claim 4,
The tail part,
An electric energy storage device including electrode leads coupled in a rivet structure, characterized in that the outer surface of the lower end is formed in a curved shape to prevent damage to the external electrode lead when coupled.
According to claim 2,
the head,
An electrical energy storage device comprising an electrode lead formed at a lower end protruding downward and coupled in a rivet structure including a plurality of fixing protrusions that contact the internal electrode lead and prevent the rivet coupling position from being shaken when pressurized.
According to claim 1,
The rivet,
An external rivet exposed to the outside of the external electrode lead and
Including an inner rivet engaged with the outer rivet
The outer rivet,
An external rivet head in contact with the outer surface of the external electrode lead, and
It is formed in a tubular shape and includes an external rivet shaft engaged with the internal rivet,
The inner rivet,
an internal rivet head buried in the hole of the internal electrode lead; and
An electric energy storage device comprising an electrode lead coupled to a rivet structure including an inner rivet shaft formed to have a length at the lower end of the inner rivet head and inserted into and coupled to the outer rivet shaft.

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