KR102501502B1 - Electrochemical energy storage device - Google Patents

Abstract

The present invention relates to an electrochemical energy storage device, and is intended to improve output while suppressing leakage of an electrolyte solution. The present invention is a storage device for storing electrochemical energy; a lower terminal plate bonded to and electrically connected to a lower portion of the storage element; a case made of a metal material having an inner space with an open portion formed on one side, a vent portion formed on a bottom surface, and a storage element inserted into the inner space through the opening portion so that the lower terminal plate faces the bottom surface; an upper terminal plate inserted into the opening of the case, electrically connected to the power storage element, fixed to the upper end of the case by beading and curling, and sealing the opening of the case; and a gasket made of rubber interposed between the upper terminal plate and the case.

Description

Electrochemical energy storage device

The present invention relates to an electrochemical energy storage device, and more particularly, to an electrochemical energy storage device capable of improving output while suppressing leakage.

In the information age, high value-added industries that collect and utilize various useful information in real time through various information and communication devices are leading, and stable energy supply is recognized as an important factor to secure the reliability of these systems.

As part of securing stable energy, an electrochemical energy storage device that converts electrical energy into chemical energy and stores it, and then converts it into electrical energy when necessary, is used.

Electrochemical energy storage devices include electrolytic capacitors, super capacitors, electric double layer capacitors (EDLCs), and lithium ion capacitors (LICs). cans, etc. The can shape includes a cylindrical shape (wound shape), a prismatic shape, and the like. At this time, the cylindrical shape is manufactured by winding the power storage element in the form of a jelly roll and then inserting it into a cylindrical case.

Cylindrical electrochemical energy storage devices, such as electric double layer capacitors (EDLCs) and lithium ion capacitors, mainly include a cylindrical case made of aluminum (Al) and a storage element embedded in the cylindrical case. At this time, the power storage element is a strip-shaped electrode laminate, specifically, a strip-shaped electrode laminate composed of an anode and cathode electrode elements and a separator interposed between the anode and cathode electrode elements in a cylindrical shape After winding, It is configured by taping the outer circumference to prevent the winding form from unraveling. The electrical storage element wound in this way is impregnated with an electrolyte and then embedded in a cylindrical case. A pair of leads electrically connecting the power storage element to the outside is formed on the top of the winding power storage element. A pair of leads are bonded to the positive electrode and the negative electrode, respectively, and protrude upward from the electrode stack.

In order to safely use such a cylindrical electrochemical energy storage device, an electrode laminate is built into a case and sealed with a rubber cap before use. At this time, the rubber cap is sealed and fixed through beading and curling with respect to the upper end of the case. The upper end of the lead protrudes out through the liver cap.

When such a cylindrical electrochemical energy storage device is used for a long time, foreign matter is generated on the surface of the rubber cap, and the life of the cylindrical electrochemical energy storage device is shortened due to the foreign matter. That is, although the rubber cap is fixed with beading and curling, leakage may occur between the case and the rubber cap due to the difference in thermal expansion coefficient between the metal case and the rubber cap.

In addition, since charging and discharging of the cylindrical electrochemical energy storage device is performed through a pair of leads, there is a limitation in performing smooth charging and discharging. For this reason, in the case of a cylindrical electrochemical energy storage device using a lead, there is a limit to improving output.

Registered Patent Publication No. 10-1508646 (Announced on April 7, 2015)

Accordingly, an object of the present invention is to provide an electrochemical energy storage device capable of solving the leakage problem caused by the use of a rubber cap.

Another object of the present invention is to provide an electrochemical energy storage device capable of improving output.

In order to achieve the above object, the present invention provides a storage device for storing electrochemical energy; a lower terminal plate having an upper surface contacted and bonded to a lower surface of the power storage element and electrically connected thereto; A metal material having an inner space with an open portion on one side, a vent portion formed on a bottom surface, and inserting the power storage element into the inner space through the opening portion so that the lower terminal plate faces the bottom surface. manufactured case; It is inserted into the opening of the case, the lower surface is contacted and bonded to the upper surface of the power storage element to be electrically connected, and is fixed to the upper end of the case by beading and curling, and the opening of the case is an upper terminal board for sealing; and a gasket made of rubber material interposed between the upper terminal plate and the case.

The power storage device includes an electrode laminate including an anode, a separator, a cathode, and an electrolyte solution, and is wound.

The lower terminal plate may be fixed to the lower portion of the case by beading or ultrasonic welding.

The upper terminal plate may include a bonding plate bonded to an upper surface of the power storage element; a gasket fitting pipe formed to protrude upward from the circumference of the bonding plate and having the gasket fitted to an outer surface thereof; and a terminal protruding higher than the gasket fitting tube on the upper surface of the bonding plate inside the gasket fitting tube.

The gasket covers the gasket fitting tube, and has a protruding portion of which a certain portion protrudes from an upper portion of the gasket fitting tube.

The protruding portion of the gasket is positioned between an upper end of the curled case and an upper end of the gasket fitting pipe.

The gasket may include a first gasket portion coupled to a lower portion of the gasket fitting pipe and into which a case portion to be beaded is inserted; and a second gasket portion connected to the first gasket portion, having an outer diameter larger than that of the first gasket portion, and including the protruding portion positioned between an upper end of the case curled at the upper end and an upper end surface of the gasket fitting pipe. includes;

The rubber material of the gasket may be butyl rubber.

The present invention also provides a storage device for storing electrochemical energy; a lower terminal plate bonded to and electrically connected to a lower portion of the power storage element; an upper terminal plate bonded to and electrically connected to an upper portion of the power storage element; a gasket made of rubber material inserted into an outer surface of the upper terminal plate; and an inner space formed with an opening portion having one side open, a vent portion formed on a bottom surface, and the power storage element being inserted into the inner space through the opening portion so that the lower terminal plate faces the bottom surface, and is embedded therein. It provides an electrochemical energy storage device including a metal case sealed to the upper terminal plate via the gasket by beading and curling.

According to the present invention, the leakage problem can be suppressed by sealing the case through beading and curling by interposing a gasket made of rubber between the upper terminal plate made of metal and the case.

In addition, the present invention improves the output characteristics compared to using a conventional lead by bonding the lower terminal plate and the upper terminal plate to the lower and upper surfaces of the electrode stack, respectively, and using them as electrode terminals of an electrochemical energy storage device. can

In the present invention, the lower terminal plate is bonded to the lower part of the case by beading or ultrasonic welding, and the upper terminal plate seals the open portion of the case with beading and curling through a gasket made of rubber, and the electrode laminate inside the case is sealed. It can be stably fixed in space.

1 is an exploded perspective view of an electrochemical energy storage device according to an embodiment of the present invention.
2 is a perspective view showing the electrochemical energy storage device of FIG. 1;
3 is a cross-sectional view of the electrochemical energy storage device of FIG. 1;

It should be noted that in the following description, only parts necessary for understanding the embodiments of the present invention are described, and descriptions of other parts will be omitted without disturbing the gist of the present invention.

The terms or words used in this specification and claims described below should not be construed as being limited to ordinary or dictionary meanings, and the inventors have appropriately used the concept of terms to describe their inventions in the best way. It should be interpreted as a meaning and concept consistent with the technical spirit of the present invention based on the principle that it can be defined in the following way. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only preferred embodiments of the present invention, and do not represent all of the technical spirit of the present invention, so various equivalents that can replace them at the time of the present application. It should be understood that there may be variations and variations.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

1 is an exploded perspective view of an electrochemical energy storage device according to an embodiment of the present invention. 2 is a perspective view showing the electrochemical energy storage device of FIG. 1; and FIG. 3 is a cross-sectional view of the electrochemical energy storage device of FIG. 1 .

1 to 3, the electrochemical energy storage device 100 according to the present embodiment includes a storage device 10, a lower terminal plate 20, a case 30 made of a metal material, and an upper terminal plate 40. and a gasket 60 made of rubber. The power storage element 10 stores electrochemical energy. The lower terminal plate 20 is bonded to and electrically connected to the lower portion of the storage element 10 . The case 30 has an inner space 33 with an open portion 31 formed on one side, a vent portion 35 formed on a bottom surface, and a lower terminal plate 20 opened toward the bottom surface. The power storage element 10 is inserted into the internal space 33 through the portion 31 and is incorporated therein. The upper terminal plate 40 is inserted into the opening 31 of the case 30 and electrically connected to the storage element 10, and is fixed to the upper end of the case 30 by beading and curling. . And the gasket 60 is interposed between the upper terminal plate 40 and the case 30 .

According to the shape of the case 30 according to the present embodiment, the electrochemical energy storage device 100 has disclosed an example implemented in a cylindrical structure, but may also be implemented in a rectangular pillar shape.

Here, the electricity storage element 10 includes a winding core 11 and an electrode laminate 13 wound around the winding core 11 . The core 11 may be removed after winding the electrode laminate 13 .

The electrode stack 13 includes an anode, a cathode, a separator, and an electrolyte. The anode generates electrons through an oxidation reaction. The cathode absorbs the generated electrons and a reduction reaction takes place. The separator is interposed between the cathode and the anode to physically separate the cathode and anode to isolate and separate the places where oxidation and reduction reactions occur. The electrolyte is an ion transfer medium that stores electrical energy in the anode and cathode. In the electrode stack 13, the positive electrode, the negative electrode, and the separator are sequentially wound around the core 11 to form a cylindrical shape as a whole. For example, the electrode stack 13 may have a cell structure forming a supercapacitor, an electric double layer capacitor (EDLC), or a lithium ion capacitor (LIC).

The case 30 is for isolating the power storage element 10 from the outside, and may be made of various materials and shapes according to the type of the power storage element 10 . The case 30 is tubular, and has an open portion 31 formed on one side and the other side blocked. The case 30 is provided with an internal space 33 into which the storage element 10 is inserted through the opening 31 . The case 30 has a vent portion 35 formed on the bottom surface of the case 30 to discharge the gas generated during operation of the electrochemical energy storage device 100 to the outside of the case 30 when the internal space 33 is filled with a certain pressure or more. there is. A metal material such as aluminum, stainless steel or tin-plated steel may be used as the material of the case 30 .

In case 30, "B" represents the beading portion, and "C" represents the curling portion. The beading portion is formed concave inward from the outer surface of the case 30 . The curling part is formed by bending the upper end of the case 30 in a C shape and bringing it into close contact with the upper surface of the upper terminal plate 40 with the gasket 60 interposed therebetween. Due to this, the case 30 and the upper terminal plate 40 are electrically separated by the gasket 60 .

The upper surface of the lower terminal plate 20 is bonded to the lower surface of the power storage element 10 and electrically connected thereto. A laser welding or ultrasonic welding method may be used as a bonding method of the lower terminal plate 20 . The lower terminal plate 20 is fixed to the lower portion of the case 30 by beading or ultrasonic welding. In this embodiment, an example in which the lower terminal plate 20 is fixed by beading has been disclosed, and “B1” indicates the corresponding part.

The lower surface of the upper terminal plate 40 is bonded to the upper surface of the power storage element 10 in contact with it. A laser welding or ultrasonic welding method may be used as a bonding method of the upper terminal plate 40 .

In this case, the lower terminal plate 20 and the upper terminal plate 40 may be made of the same metal material as the case 30 .

In addition, since the upper surface of the lower terminal plate 20 and the lower surface of the upper terminal plate 40 are contacted and bonded to and electrically connected to the lower and upper surfaces of the electrode stack 13, respectively, the electrochemical energy storage according to the present embodiment The output characteristics of the device 100 may be improved. That is, in the past, charging and discharging was performed only through a pair of leads, but in the electrochemical energy storage device 100 according to the present embodiment, the upper surface of the lower terminal board 20 and the lower surface of the upper terminal board 40 are higher than the conventional leads. This is because charging and discharging is performed through the lower terminal plate 20 and the upper terminal plate 40 having a wide contact area due to being bonded and electrically connected while being in contact with the lower and upper surfaces of the electrode stack 13, respectively. For example, the upper terminal plate 40 may be used as a negative terminal, and the case 30 connected to the lower terminal plate 20 may be used as a positive terminal.

The upper terminal plate 40 includes a bonding plate 41, a gasket fitting pipe 43, and a terminal 45. Bonding plate 41 is bonded to the upper surface of power storage element 10 . The gasket fitting pipe 43 is formed to protrude upward from the periphery of the joint plate 41, and the gasket 60 is inserted into the outer surface. Further, the terminal 45 protrudes higher than the gasket fitting pipe 43 from the upper surface of the bonding plate 41 inside the gasket fitting pipe 43.

Further, the gasket 60 is made of a rubber material having insulating properties, and suppresses leakage of electrolyte between the case 30 and the upper terminal plate 40 . The gasket 60 may be provided in a form inserted into the outer surface of the upper terminal plate 40 . Butyl rubber may be used as a material for the gasket 60 .

The gasket 60 covers the gasket fitting pipe 43 and has a protrusion 65 with a certain portion protruding from the top of the gasket fitting pipe 43 . The protrusion 65 of the gasket 60 is located between the top of the case 30 to be curled and the top of the gasket fitting pipe 43. That is, the protrusion 65 blocks electrical connection between the case 30 and the upper terminal plate 40 .

This gasket 60 includes a first gasket portion 61 and a second gasket portion 63 . The first gasket part 61 is coupled to the lower part of the gasket fitting pipe 43, and the case part B to be beaded is inserted. The second gasket portion 63 is connected to the first gasket portion 61, has a larger outer diameter than the first gasket portion 61, and is formed between the upper end of the case 30 curled at the upper end and the gasket fitting pipe 43. It has a protrusion 65 located between the top surfaces.

In this way, after the lower terminal plate 20, the storage element 10, and the upper terminal plate 40 are inserted into the inner space 33 of the case 30 through the opening 31 of the case 30, the gasket 60 ), the upper end of the case 30 is brought into close contact with the upper terminal plate 40 by beading and curling to seal the open portion 31 of the case 30. That is, in the present embodiment, the opening part 31 of the case 30 is opened by beading and curling the upper terminal plate 40 with the rubber gasket 60 inserted therein without using a lead and a rubber cap. Since it can be sealed, it is possible to solve the leakage problem of the electrolyte solution and increase the rigidity against external impact. Also, the sealing of the open portion 31 of the case 30 can be performed more simply.

By bonding the lower terminal plate 20 and the upper terminal plate 30 to the lower and upper surfaces of the electrode stack 13, respectively, and using them as electrode terminals of the electrochemical energy storage device 100, it is similar to using a conventional lead. By comparison, the output characteristics can be improved.

In addition, the lower terminal plate 20 is bonded to the lower part of the case 30 by beading or ultrasonic welding, and the upper terminal plate 40 is beaded and curled through the rubber gasket 60 to open the case 30. The internal electrode laminate 13 can be stably fixed to the internal space 33 of the case 30 while sealing the 31 .

On the other hand, the embodiments disclosed in this specification and drawings are only presented as specific examples to aid understanding, and are not intended to limit the scope of the present invention. In addition to the embodiments disclosed herein, it is obvious to those skilled in the art that other modifications based on the technical idea of the present invention can be implemented.

10: power storage element
11: Kwon Shim
13: electrode laminate
20: lower terminal board
30: case
31: opening
33: inner space
35: vent part
40: upper terminal board
41: joining plate
43: gasket fitting pipe
45: terminal
60: gasket
61: first gasket part
63: second gasket part
65: protrusion
100: electrochemical energy storage device

Claims (9)

an electricity storage element that stores electrochemical energy and includes an electrode laminate;
a lower terminal plate having an upper surface contacted and bonded to a lower surface of the electrode stack of the power storage element and electrically connected thereto;
A metal material having an inner space with an open portion on one side, a vent portion formed on a bottom surface, and inserting the power storage element into the inner space through the opening portion so that the lower terminal plate faces the bottom surface. manufactured case;
Inserted into the opening of the case, the lower surface is contacted and bonded to the upper surface of the electrode stack of the power storage element to be electrically connected, and is fixed to the upper end of the case by beading and curling, an upper terminal plate sealing the opening of the case; and
A gasket made of rubber material interposed between the upper terminal plate and the case,
The upper terminal plate,
a bonding plate bonded to an upper surface of the power storage element;
a gasket fitting pipe formed to protrude upward from the circumference of the junction plate and having the gasket fitted to an outer surface thereof; and
a terminal protruding higher than the gasket fitting tube on the upper surface of the bonding plate inside the gasket fitting tube;
An electrochemical energy storage device comprising a. According to claim 1,
The electrical storage device is an electrochemical energy storage device comprising an anode, a separator, a cathode, and an electrolyte. According to claim 1,
The electrochemical energy storage device, characterized in that the lower terminal plate is fixed to the lower portion of the case by beading or ultrasonic welding. delete According to claim 1,
The electrochemical energy storage device according to claim 1 , wherein the gasket covers the gasket fitting tube and has a protruding portion protruding from an upper portion of the gasket fitting tube. According to claim 5,
The electrochemical energy storage device, characterized in that the protruding portion of the gasket is located between the upper end of the curled case and the upper surface of the gasket fitting pipe. The method of claim 5, wherein the gasket,
a first gasket portion coupled to a lower portion of the gasket fitting pipe and into which a beaded case portion is inserted; and
a second gasket portion connected to the first gasket portion, having an outer diameter larger than that of the first gasket portion, and including the protruding portion positioned between an upper end of the case curled at the upper end and an upper end surface of the gasket fitting pipe;
An electrochemical energy storage device comprising a. According to claim 1,
Electrochemical energy storage device, characterized in that the rubber material of the gasket is butyl rubber. delete

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