KR20190041852A - Guide member, Method of making stacked type battery using the guide member and Stacked type battery manufactured therefrom - Google Patents

Abstract

The present invention relates to a method for manufacturing a stacked battery. A stack battery comprises: a guide member formed of a flat plate and two rods vertically spaced on the plate; and a plurality of unit cells. The method for manufacturing a stacked battery comprises the steps of: (S1) preparing an electrode current collector having a hole formed at an end of an electrode tab; (S2) manufacturing a plurality of unit cells using an electrode and a separator using the electrode current collector; (S3) aligning the plurality of unit cells by inserting a rod of the guide member according to any one of claims 1 to 3 into the hole formed in the electrode tab end of the unit cell; and (S4) removing the guide member from the aligned plurality of unit cells.

Description

[0001] The present invention relates to a guide member, a method of manufacturing a stacked battery using the guide member, and a stacked battery manufactured from the guide member, a method of making stacked type battery using the guide member and a stacked type battery manufactured therefrom,

The present invention relates to a guide member, a method of manufacturing a stacked battery using the guide member, and a stacked battery manufactured from the method.

BACKGROUND ART [0002] In recent years, rechargeable secondary batteries have been widely used as energy sources for wireless mobile devices. The secondary battery is also attracting attention as an energy source for electric vehicles and hybrid electric vehicles, which are proposed as solutions for air pollution of existing gasoline vehicles and diesel vehicles using fossil fuels. Accordingly, the types of applications using secondary batteries are diversifying due to the advantages of secondary batteries, and it is expected that secondary batteries will be applied to many fields and products in the future.

2. Description of the Related Art Generally, a secondary battery includes a unit cell composed of a positive electrode, a negative electrode, and a separator interposed between the positive and negative electrodes. The unit cell is stacked or wound into a case in the form of a laminate sheet or a metal can, .

The electrode assembly of the anode / separator / cathode structure constituting the secondary battery is largely divided into a jelly-roll type (wound type) and a stack type (laminated type).

The jelly-roll type electrode assembly is produced by coating an electrode active material or the like on a metal foil used as a current collector, drying and pressing the electrode active material, cutting the electrode into a band shape having a desired width and length, Followed by spiral winding. Such a jelly-roll type electrode assembly can be preferably used for a cylindrical battery. However, when the jelly-roll type electrode assembly is applied to a prismatic or pouch type battery, there is a problem that the local stress is concentrated and the electrode active material is peeled off or the battery is deformed due to repeated shrinkage and expansion phenomenon during charging and discharging .

On the other hand, the stacked electrode assembly has a structure in which two or more unit cells made up of an anode and a cathode are sequentially stacked, and it is easy to obtain a square shape. However, such a stacked electrode assembly has a disadvantage in that the manufacturing process is troublesome, and further, when the impact is applied, the electrode is pushed to cause a short circuit. Particularly, in the case of a pouch-type battery having a plurality of electrode tab structures, electrodes or unit cells may not be fixed at a predetermined position, and a great deal of effort is required to obtain or maintain a precise position. Overhang control between internal electrodes is not easy. Accordingly, attempts have been made to reduce the anode area and the cathode area, but there is a problem in that the battery capacity and the cell size required in the market are limited. That is, in order to meet the cell size and capacity required in the market, it is necessary to reduce the overhang as much as possible. To do so, a technique of stacking the unit cells so that the unit cells are accurately aligned with each other is required.

As used herein, the term " overhang " means that the anode area is designed to be wide enough to cover the anode in order to prevent lithium deposition of the battery. When the anode and the anode are stacked with the separator interposed therebetween, Quot; is understood to mean a further extended portion, for example, a cathode edge margin.

Meanwhile, a Hi-pot inspection process may be included in the manufacturing process of the battery. The Hi-pot test is a dielectric strength test that intentionally evaluates the short-cut by applying a high voltage to the battery to prevent the problem of insulation by the active material. Such a Hi-pot test is necessary to confirm the safety of a battery. However, charge is formed or accumulated in the unit cell through such a test, and these charges attract the surrounding dust or foreign matter to the electrostatic force and cause the unit cell or the battery to be contaminated .

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

One aspect of the present invention is to provide an electrode tab in which a hole is formed.

Another aspect of the present invention is to provide a guide member for use in manufacturing a stacked battery.

Another aspect of the present invention is to provide a method of manufacturing a stacked battery in which a plurality of unit cells are aligned in position using the electrode tab and the guide member.

Another aspect of the present invention is to provide a stacked battery in which foreign matter contamination is reduced by using the electrode tab and the guide member.

According to a first aspect of the present invention, there is provided a guide member formed of a flat plate and two rods vertically spaced on the plate.

According to a second aspect of the present invention, the guide member in the first aspect may be made of a charge-eliminating substance.

According to a third aspect of the present invention, in the first or second aspect, the guide member is made of conductive acrylic fiber, carbon fiber, metal fiber, conductive powder impregnated fiber, dielectric fiber, Or at least one selected from the group consisting of

According to a fourth aspect of the present invention, there is provided a method of manufacturing a stacked battery including a plurality of unit cells, comprising the steps of: (S1) preparing an electrode current collector having a hole formed at an end of the electrode tab; (S2) fabricating a plurality of unit cells using an electrode and a separator using the electrode current collector; (S3) aligning a plurality of unit cells by inserting a rod of a guide member according to any one of the first to third aspects into a hole formed in an electrode tab end of the unit cell; And (S4) fixing the plurality of unit cells and removing the guide member from the unit cells.

According to a fifth aspect of the present invention, in the fourth aspect, a Hi-pot test may be performed on the unit cell between steps (S2) and (S3).

According to the sixth aspect of the present invention, in the fifth aspect, the guide member is made of the antistatic substance, and the charge in the unit cell formed from the Hi-pot inspection can be removed.

According to a seventh aspect of the present invention, there is provided a stacked battery comprising a plurality of unit cells, wherein electrode tabs in each of the unit cells are coupled to electrode leads, Wherein the electrode tab is provided with the electrode tab and the electrode tab is combined with the electrode lead in a state where the electrode tab is overlapped with the electrode lead.

According to the present invention, it is possible to provide a stacked battery in which unit cells are aligned in a predetermined position by a hole formed in an electrode tab and a guide member.

Further, since a plurality of unit cells can be more accurately and precisely aligned in position, overhang control becomes possible, so that the anode size limitation due to overhang is reduced or eliminated. Thus, the anode size can be maximized.

In addition, since the guide member made of the antistatic substance has the effect of eliminating the charge formed in the cell during Hi-pot inspection. As a result, the electrostatic force of the battery is reduced, so that the problems of process deterioration due to dust contamination and the like can be improved and a stacked battery with reduced foreign matter can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and together with the description of the invention serve to further the understanding of the technical idea of the invention, It should not be construed as limited.
1 is a top plan view of a unit cell according to an aspect of the present invention.
2 is a schematic view of a guide member according to an embodiment of the present invention used for aligning an electrode tab.
3 is a view schematically showing an embodiment of the present invention in which a guide member is applied to a perforated tab of one unit cell.
4 is a side view schematically showing an embodiment of the present invention in which a guide member is applied to perforated tabs of a plurality of unit cells.
5 is a schematic view of an embodiment of the present invention in which a tape is applied to the side of a plurality of unit cells.
6 is a side view schematically showing a plurality of unit cells in which a guide member is removed after alignment is completed by a guide member, according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor may designate the concept of a term appropriately in order to describe its own invention in the best way possible. It should be interpreted as meaning and concept consistent with the technical idea of the present invention. Therefore, the constitutions described in the embodiments described herein are merely the most preferred embodiments of the present invention, and are not intended to represent all of the technical ideas of the present invention. Therefore, various equivalents which can be substituted at the time of application It should be understood that variations can be made.

The stacked battery of the present invention may be manufactured by housing an electrode assembly in which two or more unit cells are stacked in a pouch-shaped battery case including a battery case, for example, an aluminum laminate sheet. The pouch-shaped battery case may further include an electrolyte in addition to the electrode assembly.

The unit cell is formed by alternately laminating a cathode, a separator, and an anode. The unit cell includes a cathode-separator-anode-separator-cathode structure as well as a cathode-separator- The number of the electrodes and the number of the separator, as well as the configuration comprising the cathode-separator-anode, may not be particularly limited.

The electrode included in the unit cell has electrode active material on at least one surface of the current collector, and at least one end of the electrode current collector forms an unoccupied active material and is used as an electrode tab.

FIG. 1 is a top view schematically showing a unit cell according to an embodiment of the present invention, and FIG. 1 does not show the overhang portion of the anode / cathode. 1, an electrode tab 110 is extended from one electrode constituting the unit cell 100, another electrode tab 120 is protruded from another electrode, and the electrode tab 110 110 and 120 are formed with holes 111 and 121, respectively.

The electrode tab may have one positive electrode tab and one negative electrode tab or one positive electrode tab and one negative electrode tab, respectively, in one unit cell, depending on the structure of the unit cell. Even when one positive electrode tab and one negative electrode tab are formed in one unit cell, since the stacked battery according to the present invention is composed of a plurality of unit cells, each of the positive electrode tab and the negative electrode tab included in the stacked battery includes a plurality .

The size of the hole formed in the electrode tab should be determined in consideration of the rod size of the guide member. If the hole is too large, the electrode can be moved without being aligned in the correct position even if it is fixed by the rod of the guide member, so that the desired positive alignment can not be achieved. In addition, the effect of static elimination by the guide member formed of the antistatic substance may not be significant. On the other hand, if the hole is too small or is exactly the same as the guide member rod size, the electrode tab may be bent or damaged.

In addition, when the unit cells are stacked through the guide member in relation to the electrode tapped holes in the other unit cells, the electrode tapped holes of the unit cells are set at the same positions so that the unit cells are aligned in the correct positions . Therefore, it is important that the holes of the electrode tabs of a plurality of unit cells are formed at precise positions without error. In addition, the size and shape of the hole should be the same.

The shape of the hole is not particularly limited as long as it does not meet the object of the present invention, and for example, it may have a shape such as a circle, a rectangle, a square, a rhombus, and an ellipse. It is preferable that the guide member has the same shape as the rod end face of the guide member.

FIG. 2 is a schematic view of a guide member used for aligning an electrode tab according to an embodiment of the present invention, and FIG. 3 is a schematic view showing a state immediately before one unit cell is applied to the guide member.

Referring to FIGS. 2 and 3, the guide member 200 is formed of a flat plate 230 on which a unit cell to be stacked is placed, and two rods 210 and 220 spaced vertically on the plate.

Preferably, the plate 230 of the guide member has a size larger than that of the unit cell so that an area where the unit cell is sufficiently placed is secured.

The two rods 210 and 220 are positioned on the plate 230 so as to correspond to the holes 111 and 121 formed in the positive electrode tab and the negative electrode tab, respectively, It is desirable that the cells are stationary and do not move. In addition, the two rods 210 and 220 have appropriate hardness so that they are not bent or bent in the process of being inserted into the holes of the unit cell electrode tabs. In addition, the two rods 210 and 220 are preferably designed to have a height sufficiently larger than the stack height of the electrode tabs of the plurality of unit cells constituting the stacked electrode assembly.

The sectional shape of the rod is not limited to a great extent. However, as described above, when the electrode taps are supported on the rods so that the unit cells are not separated from the fixed position and the electrode tabs are inserted into the rods of the guide members, It is preferable to have the same shape as the hole. In addition, the cross-sectional size of the rod must be such that when the rod is inserted into the electrode tapped hole, the effect of eliminating the electrostatic force can be generated, and at the same time, the unit cell is fixed by the rod. Therefore, It should be designed so that it is not bent or damaged.

The guide member may be made entirely or at least partially made of an antistatic material and may have the effect of removing static electricity formed in the unit cell. More specifically, the antistatic material may be a conductive fiber or a conductive metal fiber. As a non-limiting example, the antistatic material may be formed by plating a nickel or copper metal layer on the surface of a non-conductive material such as a fiber or by using a material in which a conductive material such as a metal foil or a metal wire is wound around a urethane-based porous resin, or a conductive acrylic fiber, At least one selected from the group consisting of metal fiber, conductive powder impregnated fiber, dielectric fiber, and magnetic fiber.

According to another aspect of the present invention, there is provided a method of manufacturing a stacked battery using the electrode tab and the guide member.

The method for manufacturing the electrode tab according to the present invention is not particularly limited as long as it is in accordance with the object of the present invention. For example, the electrode tab may be formed by notching a part of the non-coated portion where the electrode active material layer is not coated, And a hole is formed in the electrode tab in the notching process.

Then, a Hi-pot inspection process can be performed by laminating (lamination) the positive electrode and the negative electrode with the separator interposed therebetween. Charge is formed or accumulated in the unit cell after the Hi-pot test, and this charge causes the contamination of the foreign matter by the static electricity in the subsequent process, so that the battery itself is contaminated and the process is also deteriorated.

The unit cells are stacked while fixing the unit cells to constitute the stacked electrode assembly one by one to the guide member according to the present invention through the electrode tapped holes. In this process, the inside circumference of the electrode tapped hole is brought into contact with the guide member rod, and the charge of the unit cell is reduced or eliminated due to the antistatic substance of the guide member.

4 is a view schematically showing an embodiment in which a guide member according to an embodiment of the present invention is applied to a plurality of unit cells. 4, the positive electrode tabs 110a to 110e and the negative electrode tabs 120a to 120e of the plurality of unit cells 100a, 100b, 100c, 100d and 100e are connected to the rods 210 and 220 of the guide member 200, And is fixed to the guide member 200.

Then, if necessary, the guide members are removed from a plurality of unit cells aligned in a fixed position while fixing the unit cells with a jig, a tape or the like.

5, tape 300 is applied along the sides of a plurality of unit cells 100a, 100b, 100c, 100d, and 100e to form a plurality of unit cells 100a, Thereby preventing the cells from moving or moving. The position and the number of application unit cells of the tape can be prevented from moving or moving. In addition to the position shown in FIG. 5, the position where the electrode tab is located and / Position. The tape may be applied only to the side portion as shown in FIG. 5, but may be applied in a manner to surround a plurality of unit cells when necessary. The material of the tape is not particularly limited as long as it meets the object of the present invention. For example, an adhesive material may be applied to a surface of an insulating material, which is applied to a plurality of unit cells.

6 is a view schematically showing a plurality of unit cells in which a guide member is removed after alignment of unit cells is completed by a guide member, according to an embodiment of the present invention. Referring to FIG. 6, it can be seen that a plurality of unit cells 100a, 100b, 100c, 100d, and 100e are aligned in parallel with each other.

Then, the positive electrode tabs are welded to the positive electrode tabs, the negative electrode tabs are welded to the negative electrode tabs, and then the welded electrode tabs are connected to the electrode leads by welding or the like. The welding of the electrode tab may be performed by a general welding method in the art, and is not particularly limited. For example, welding may be performed in a direction perpendicular to the weld surface of the electrode tab after the welds are positioned to overlap with each other in such a manner as to be bent in the vertical direction of the unit cell, and may be welded by various methods including laser welding and ultrasonic welding. have.

The combination of the electrode tab and the electrode lead can be performed after positioning the hole located in the electrode tab to overlap with the electrode lead. For example, ultrasonic welding may be performed. In order to secure welding reliability, laser welding may be performed after ultrasonic welding.

From the above, it can be seen that a stacked battery comprising a plurality of unit cells, wherein the electrode tabs in each of the unit cells are coupled to the electrode leads, and the stacked cells in which the electrode tabs are welded in overlapping relation with the electrode leads are obtained .

Alternatively, the electrode tab may be connected to the electrode lead by welding the electrode tab such that the hole located in the electrode tab is included in the welded portion, then removing the electrode tab hole portion in the process of assembling the welded portion, . The connection between the electrode tab and the electrode lead may be accomplished by ultrasonic welding and may be accomplished by additional laser welding after ultrasonic welding to assure welding reliability, but the present invention is not limited thereto.

While the present invention has been described with reference to the particular embodiments and drawings, it is to be understood that the present invention is not limited thereto and that various changes and modifications will be apparent to those skilled in the art. And various modifications and variations are possible within the scope of the appended claims.

Claims (7)

A guide member comprising a flat plate and two rods spaced vertically on the plate.
The method according to claim 1,
Wherein the guide member is made of an antistatic substance.
3. The method of claim 2,
Wherein the guide member is at least one member selected from the group consisting of conductive acrylic fiber, carbon fiber, metal fiber, conductive powder impregnated fiber, dielectric fiber, and magnetic fiber.
1. A method for manufacturing a stacked cell comprising a plurality of unit cells,
(S1) preparing an electrode current collector having a hole formed at an end of the electrode tab;
(S2) fabricating a plurality of unit cells using an electrode and a separator using the electrode current collector;
(S3) aligning a plurality of unit cells by inserting a rod of the guide member according to any one of claims 1 to 3 into a hole formed in an electrode tab end of the unit cell; And
(S4) fixing the plurality of unit cells and removing the guide members from the unit cells;
≪ / RTI >
5. The method of claim 4,
And a Hi-pot test is performed on the unit cell between steps (S2) and (S3).
6. The method of claim 5,
Wherein the guide member is made of an antistatic material and the charge in the unit cell formed from the Hi-pot test is removed.
A stacked battery comprising a plurality of unit cells,
Wherein the electrode tabs of the unit cells are coupled to the electrode leads, the electrode tabs are formed with holes at the ends thereof, and the electrode tabs are combined with the electrode leads in a state where the electrode tabs are overlapped with the electrode leads, Shaped battery.

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