WO2018097606A1

WO2018097606A1 - Electrode assembly manufacturing device and electrode assembly manufacturing method by same electrode assembly manufacturing device

Info

Publication number: WO2018097606A1
Application number: PCT/KR2017/013375
Authority: WO
Inventors: 이민재; 이주성
Original assignee: 주식회사 엘지화학
Priority date: 2016-11-23
Filing date: 2017-11-22
Publication date: 2018-05-31
Also published as: KR20180057847A; CN208539012U; KR102080256B1

Abstract

The present invention relates to an electrode assembly manufacturing device capable of preventing a short circuit from being caused inside a second battery due to an external impact, and a method for manufacturing an electrode assembly by the electrode assembly manufacturing device. Further, the present invention comprises: a transfer part for unwinding and transferring a first electrode, a separation film, a second electrode; a stacking part for forming an electrode laminate by stacking the first electrodes, the separation films, and the second electrodes, which have been transferred from the transfer part, in the order of the first electrode, the separation film, the second electrode, the separation film, and the first electrode; and a bonding part for bonding ends of the at least two neighboring separation films in the electrode laminate to each other.

Description

Electrode assembly manufacturing apparatus and electrode assembly manufacturing method using the electrode assembly manufacturing apparatus

Citation with Related Applications

This application claims the benefit of priority based on Korean Patent Application No. 2016-0156195 dated November 23, 2016, and all the contents disclosed in the documents of that Korean patent application are incorporated as part of this specification.

Technical Field

The present invention relates to an electrode assembly manufacturing apparatus and an electrode assembly manufacturing method using the electrode assembly manufacturing apparatus, and more particularly, an electrode assembly manufacturing apparatus and an electrode assembly manufacturing apparatus capable of preventing a short inside the secondary battery due to an external impact. It relates to a method for producing an electrode assembly by.

As the development and demand for mobile devices increases, the demand for secondary batteries as energy sources is increasing rapidly. Among them, many researches have been conducted and commercialized and widely used for lithium secondary batteries with high energy density and discharge voltage. It is used.

The secondary battery has a structure in which an electrode assembly having a separator interposed between a positive electrode and a negative electrode is stacked or wound and sealed in a case in which an electrolyte is impregnated.

The electrode assembly of the secondary battery has a jelly-roll type wound in a state of interposing the electrode assembly and a plurality of positive and negative electrodes coated with electrode active materials on both sides of a current collector foil having a predetermined unit size through a separator. Ecologically divided into stack-type (stack-type) sequentially stacked.

The jelly-roll type electrode assembly is coated with an electrode active material or the like on a metal foil used as a current collector, dried and pressed, cut into bands of a desired width and length, and the membrane is separated by using a separator to form a spiral. It is manufactured by winding.

Such a jelly-roll type electrode assembly may be preferably used in a cylindrical battery, but in application to a square or pouch type battery, the stress is locally concentrated and the electrode active material is peeled off or the battery shrinks due to shrinkage and expansion phenomenon repeated during charge and discharge. There is a problem that causes deformation.

On the other hand, the stacked electrode assembly is a structure in which a plurality of anode and cathode unit cells are sequentially stacked, and it is easy to obtain a rectangular shape, but when the manufacturing process is complicated and an impact is applied, the electrode is pushed to cause a short circuit. There are disadvantages.

In order to solve this problem, the electrode assembly of the advanced structure of the jelly-roll type and the stacked form, a full cell or anode (cathode) / separator / cathode of a certain unit size of the anode / separator / cathode structure A stack-and-foldable electrode assembly was developed in which a bicell of (anode) / separator / anode (cathode) structure was folded using a continuous separation film of a long length, which is a conventional Korean patent application publication. 2001-82058.

The conventional bicell type electrode assembly has a problem that damage to the electrode may occur when the separator is not bonded unless the gap between the cathode electrode and the separator is maintained at a constant interval.

In addition, when an external impact such as a drop, the electrode between the separator is protruded to the outside there is a problem that may cause a short inside the secondary battery.

Therefore, the present invention has been made to solve the above problems, the object of the present invention is to prevent the short inside the secondary battery due to external shock and to improve the stability of the secondary battery manufacturing apparatus and the electrode assembly manufacturing It is to provide a method for producing an electrode assembly by the device.

Electrode assembly manufacturing apparatus according to an embodiment of the present invention is to be laminated in the order of the first electrode, the separator, the transfer unit for unwinding and transferring the second electrode, the first electrode, the separator, the second electrode, the separator, the first electrode It characterized in that it comprises a laminate for stacking the first electrode, the separator, the second electrode received from the transfer unit to form an electrode laminated body and a bonding portion for bonding the ends of at least two neighboring membrane neighboring in the electrode laminate do.

The bonding part is a roller that rotates and presses the separator, and the roller may rotate in a direction opposite to the advancing direction of the electrode laminate.

The surface of the roller may be embossed or engraved.

The bonding part may include a heating wire that generates heat, and heat-compresses end portions of the plurality of separation membranes.

The bonding part may be formed of a pair of rollers, and end portions of the plurality of separation membranes may be bonded in a direction facing each other between the pair of rollers.

The second electrode may be formed between a plurality of separators, and the second electrode may be fixed by a plurality of separators whose ends are bonded to each other by the bonding part.

In the electrode laminate, a plurality of the separators are larger than the first electrode and the second electrode, and an end portion of the plurality of separators protrudes from the side of the electrode laminate, and an end portion of the bonding portion protrudes from the side of the electrode laminate. It may be located to correspond to the ends of the plurality of separation membrane.

The joining portion is formed of a pair of press plates that are pressed in an opposite direction, and end portions of the plurality of separators are joined in a direction facing each other by the pair of press plates when positioned between the pair of press plates. Can be.

The pair of press plates may be embossed or indented on the surface.

Electrode assembly manufacturing method using an electrode assembly manufacturing apparatus according to an embodiment of the present invention is a transfer step of unwinding and transporting the first electrode, the separator, the second electrode, the first electrode, the separator, the second electrode, the separator, the first Laminating step of laminating the first electrode, the separator, and the second electrode transferred in the transfer step so as to be stacked in the order of the electrodes; and bonding the ends of at least two neighboring separators adjacent to each other after the electrode step. It is characterized by.

In the bonding step, the ends of at least two neighboring separators may be heat-compressed with each other.

In the bonding step, a pair of rollers or a pair of press plates may be bonded to each other in the direction in which the ends of at least two neighboring separators face each other.

In the bonding step, the ends of at least two neighboring separators may be bonded to each other to fix a second electrode located between the separators.

According to the present invention, there is an effect of preventing the internal short even in the external impact, such as falling of the secondary battery.

According to the present invention, it is easy to apply to the existing secondary battery manufacturing process has the advantage that the additional process is not complicated.

According to the present invention, there is an effect of improving the stability by preventing contact between the positive electrode and the negative electrode.

1 is a configuration diagram schematically showing the electrode assembly manufacturing apparatus of the present invention from the side.

Figure 2 is a plan view showing a partially enlarged planar view of the electrode laminated body is transferred toward the bonding portion according to an embodiment of the present invention.

3 is a partially enlarged view illustrating a state in which end portions of the separation membrane are bonded by the bonding portion according to an embodiment of the present invention.

Figure 4 is a side view schematically showing the bonding portion according to another embodiment of the present invention.

FIG. 5 is a side view schematically showing the cemented portion according to another embodiment of the present invention. FIG.

6 is a flowchart illustrating a method of manufacturing an electrode assembly by the electrode assembly manufacturing apparatus of the present invention.

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

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

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

As shown in Figure 1, the electrode assembly manufacturing apparatus according to an embodiment of the present invention, the transfer unit (1), the first electrode 10, the separation membrane 20, the second electrode 30 unwinding and conveying The first electrode 10 and the separator 20 received from the transfer unit so as to be stacked in the order of the first electrode 10, the separator 20, the second electrode 30, the separator 20, and the first electrode 10. In addition, the stacking unit 3 stacking the second electrode 30 to form the electrode stack 100 and the end portions 21 of the at least two separation membranes 20 adjacent to each other in the electrode stack 100 are connected to each other. And a fitting part 5 to be bonded.

The transfer unit 1 unwinds the first electrode 10, the separator 20, and the second electrode 30 from each of the wound first electrode 10, the separator 20, and the second electrode 30, and bonds them together. It is for conveying in the direction of the part 5.

The transfer unit 1 may be formed of any one or more of a transfer roller or a conveyor belt.

The stacking unit 3 is for stacking the first electrode 10, the separator 20, and the second electrode 30 transferred by the transfer unit 1.

The stacking unit 3 may stack the first electrode 10 and the second electrode 30 so as to be separated by the separator 20. In the preferred embodiment of the present invention, the first electrode 10 and the separator 20 may be stacked. ), The second electrode 30, the separator 20, and the first electrode 10 are stacked in this order to describe a bicell shape in which the same electrode is positioned on both outermost sides, but is not limited thereto. In the present invention, the electrode stacked structure 100 has a shape or the first electrode 10 and the second electrode 30 if the first electrode 10 and the second electrode 30 are stacked to be separated by the separator 20. The number of stacked layers of the separator 20 may not be limited.

The stacking unit 3 may be stacked using any one or more of heat or pressure to stack the electrode stacks 100.

The first electrode 10 and the second electrode 30 forming the electrode stacked structure 100 may be any one of a positive electrode to which a positive electrode active material is applied and a negative electrode to which a negative electrode active material is applied to form an upper electrode.

That is, when the first electrode 10 forms an anode, when the second electrode 30 forms a cathode, and when the first electrode 10 forms an anode, the second electrode 30 may form an anode. .

The positive electrode generally be panil aluminum, and the positive electrode active material may be a lithium-containing chalcogenides or lithium transition metal oxide compound such as a knife _{_{_{LiCoO 2, LiNiO 2, LiMnO 2}}} , LiMnO 4.

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

The separator 20 is, for example, any selected from the group consisting of polyethylene (PE), polystyrene (PS), polypropylene (PP) and a copolymer of polyethylene (PE) and polypropylene (PP). It can be prepared by coating a polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP co-polymer) on one substrate.

When the electrode stack 100 forms the first electrode 10, the separator 20, the second electrode 30, the separator 20, and the first electrode 10, the pair of separators 20 One of the positive electrode and the negative electrode may be located.

The stacking unit 3 may be formed at the outlet side for discharging the

electrodes

10 and 20 and the separator 20 from the transfer unit 1.

Therefore, the stacking unit 3 according to the present invention has an advantage in that it can be implemented by installing at the end of the process of transporting the electrode assembly in the conventional electrode assembly manufacturing process, it is easy to implement.

FIG. 2 is a schematic view showing, in part, an enlarged plan view of the electrode stacked body being transferred toward the cemented portion 5 according to an embodiment of the present invention.

As shown in FIG. 2, the separator 20 is larger than the first electrode 10 and the second electrode 30 to prevent a short circuit between the first electrode 10 and the second electrode 30. It can be formed large.

Therefore, the end portion 21 of the separator 20 in the electrode laminate 100 may be formed to protrude toward the side of the electrode laminate 100.

In addition, the bonding part 5 may be disposed at a position corresponding to the end 21 of the separator 20 in the electrode stack 100 to be transferred.

Figure 3 is a state diagram showing the use of the side portion of the enlarged part of the separation membrane is bonded to the bonding portion according to an embodiment of the present invention.

As shown in FIG. 3, the electrode assembly manufacturing apparatus according to the exemplary embodiment of the present invention rotates in a direction (d1) and a reverse direction (d2) in which the bonding portion 5 transfers the electrode laminate 100 and the separation membrane ( It is possible to form a pair of rollers for pressing the end portion 21 of 20).

And the pair of rollers forming the bonding portion 5 may be bonded in a direction facing each other end 21 of the plurality of separation membrane (20).

In addition, the pair of rollers forming the cemented portion 5 may have a built-in heating wire to heat and compress the end portions 21 of the plurality of separators 20 in a direction facing each other, thereby increasing the cemented effect.

As such, when the end portions 21 of the plurality of separators 20 are bonded to each other, the second electrodes 30 stacked between the plurality of separators 20 are fixed between the separators 20 so that the secondary battery may receive an external shock such as a drop. Even if it receives, the 1st electrode 10 and the 2nd electrode 30 can be prevented from short-circuiting.

That is, since the second electrode 30 is fixed by the separator 20 stacked on both sides, the first electrode 10 and the second electrode 30 are not shorted to each other, thereby improving stability of the secondary battery. .

As shown in Figure 4, according to another embodiment of the present invention, the cemented portion 5a may be embossed or indented on the surface of the roller.

If an embossed or engraved surface is formed on the surface of the roller, the bonding force of the ends 21 of the plurality of separation membranes 20 compressed between the pair of rollers may be increased.

On the other hand, if the embossed or intaglio formed on the pair of rollers are formed to cross between the pair of rollers facing each other can increase the bonding rate of the end 21 of the plurality of separation membrane 20.

As shown in Figure 5, according to another embodiment of the present invention, the cemented portion (5b) may be formed as a pair of press plate pressed in the opposite direction.

When the electrode laminate 100 moves between the pair of press plates, the end 21 of the plurality of separation membranes 20 is compressed between the pair of press plates that reciprocate (d3) in a direction facing each other. The ends 21 of the two separation membranes 20 may be bonded to each other.

In addition, the pair of press plates may have a built-in heating wire and may compress the ends 21 of the plurality of separation membranes 20 while heating.

In addition, the pair of press plates are indented or embossed in a direction facing each other to compress the end 21 of the plurality of separation membranes 20 to each other, the bonding force of the end 21 of the plurality of separation membranes 20 are bonded together Can increase.

In addition, the pair of press plates may further improve the bonding force of the end portions 21 of the plurality of separation membranes 20 formed by bonding the intaglio or embossed portions formed in a direction facing each other.

Hereinafter, a method of manufacturing an electrode assembly by the manufacturing apparatus of the present invention will be described in detail with reference to the drawings.

As shown in Figure 6, the electrode assembly manufacturing method by the electrode assembly manufacturing apparatus of the present invention includes a transfer step (S1), lamination step (S2) and bonding step (S3).

The transfer step S1 is a step of unwinding the first electrode 10, the separator 20, and the second electrode 30 wound as shown in FIG. 1, and transferring the wound first electrode 10, the separator 20, and the second electrode 30.

In the stacking step S2, the first electrode 10, the separator 20, and the second electrode 30 to be transferred are stacked such that the first electrode 10 and the second electrode 30 are separated by the separator 20. To form the electrode laminate 100.

In this case, the stacking step (S2) is such that the electrode stack 100 is stacked in the order of the first electrode 10, the separator 20, the second electrode 30, the separator 20, and the first electrode 10. can do.

The bonding step S3 is a step of bonding the end portions 21 of at least two neighboring separators 20 adjacent to each other after the stacking step S2.

And the bonding step (S3) is a pair of rollers or a pair of presses to secure the second electrode 30 located between the separation membrane 20 by bonding the end 21 of the at least two separation membranes 20 adjacent to each other. A plate may be used to bond the end portions 21 of at least two neighboring membranes 20 to each other by heat compression.

As described above, according to the present invention, there is an effect of preventing the internal short even in the external impact such as falling of the secondary battery.

In addition, according to the present invention, it is easy to apply to the existing secondary battery manufacturing process has the advantage that the additional process is not complicated.

In addition, according to the present invention, there is an effect of improving the stability by preventing contact between the positive electrode and the negative electrode.

The electrode assembly manufacturing apparatus and the electrode assembly manufacturing method by the electrode assembly manufacturing apparatus according to the present invention as described above with reference to the illustrated drawings, but the present invention is not limited to the embodiments and drawings described above, Various implementations are possible by those skilled in the art within the scope of the claims.

Claims

A transfer unit 1 which unwinds and transfers the first electrode 10, the separator 20, and the second electrode 30;

The first electrode 10 and the separator 20 received from the transfer unit so as to be stacked in the order of the first electrode 10, the separator 20, the second electrode 30, the separator 20, and the first electrode 10. ), A stacking unit 3 stacking the second electrodes 30 to form the electrode stack 100; And

A bonding part 5 for bonding the end portions 21 of the at least two separation membranes 20 adjacent to each other in the electrode stack 100 to each other; Electrode assembly manufacturing apparatus comprising a.
The method according to claim 1,

The bonding part 5 is a roller which rotates and pressurizes the separation membrane 20.

The roller assembly manufacturing apparatus, characterized in that for rotating in the opposite direction to the traveling direction of the electrode laminated body (100).
The method according to claim 2,

Electrode assembly manufacturing apparatus, characterized in that the surface of the roller is embossed or engraved.
The method according to claim 1 or 2,

The bonding part (5) has a built-in heating wire that generates heat, and electrode assembly manufacturing apparatus, characterized in that for heating and pressing the end portion 21 of the plurality of separation membrane (20).
The method according to claim 1 or 2,

The bonding part 5 is formed of a pair of rollers, the electrode assembly manufacturing apparatus, characterized in that the end portion 21 of the plurality of separation membrane 20 is bonded in a direction facing each other between the pair of rollers. .
The method according to claim 5,

The second electrode 30 is formed between a plurality of separation membranes 20, and the second electrode 30 is a plurality of separation membranes 20 in which end portions 21 are bonded to each other by the bonding part 5. Electrode assembly manufacturing apparatus characterized in that is fixed by).
The method according to claim 1,

In the electrode stack 100, the plurality of separators 20 are larger in size than the first electrode 10 and the second electrode 30, so that an end portion 21 has a side surface of the electrode stack 100. Protrudes into

The end of the bonding portion (5) is an electrode assembly manufacturing apparatus, characterized in that it is located to correspond to the end (21) of the plurality of separation membrane (20) protruding to the side of the electrode laminated body (100).
The method according to claim 1,

The bonding portion 5 is formed of a pair of press plates that are pressed in the opposite direction, and the end portions 21 of the plurality of separation membranes 20 are positioned between the pair of press plates. Electrode assembly manufacturing apparatus characterized in that the bonding in the direction facing each other by a press plate.
The method according to claim 8,

The pair of press plate is an electrode assembly manufacturing apparatus, characterized in that the surface is embossed or engraved.
A transfer step (S1) of unwinding and transferring the first electrode 10, the separator 20, and the second electrode 30;

The first electrode 10 and the separator transferred in the transfer step such that the first electrode 10, the separator 20, the second electrode 30, the separator 20, and the first electrode 10 are stacked in this order. 20, a stacking step of stacking the second electrode 30 (S2); And

A bonding step (S3) of bonding the end portions 21 of at least two neighboring membranes 20 adjacent to each other after the electrode step S2; Electrode assembly manufacturing method comprising a.
The method of claim 10,

The bonding step (S3) is a method for manufacturing an electrode assembly, characterized in that the heat-compression bonding the end (21) of at least two neighboring separation membrane (20) with each other.
The method of claim 10,

The bonding step (S3) using the pair of rollers or a pair of press plate to manufacture the electrode assembly, characterized in that the bonding in the direction facing each other end 21 of the at least two separation membrane 20 adjacent to each other Way.
The method of claim 10,

In the bonding step (S3), the electrode assembly is manufactured by fixing the second electrode 30 located between the separators 20 by bonding the end portions 21 of at least two neighboring separators 20 to each other. Way.