KR102078801B1 - Electrode assembly and manufacturing method of electrode assembly - Google Patents

Abstract

The present invention relates to an electrode assembly and a method of fabricating the electrode assembly of the stacked structure and folding the electrode on the separator.
In addition, the present invention is developed to be foldable (folding), the separator member is formed with a plurality of wings, the first electrode stacked on the separator member and the plurality of wings laminated and laminated to the separator member and the separator member It characterized in that it comprises a second electrode separated from the first electrode by.

Description

Electrode assembly and electrode assembly manufacturing method {ELECTRODE ASSEMBLY AND MANUFACTURING METHOD OF ELECTRODE ASSEMBLY}

The present invention relates to an electrode assembly and a method for manufacturing the electrode assembly, and more particularly, to an electrode assembly and a method of manufacturing the electrode assembly of the stacked structure and folding the electrode on the separator.

Cells or batteries that generate electric energy through physical or chemical reactions of materials and supply power to the outside cannot obtain AC power supplied to buildings according to the living environment surrounded by various electrical and electronic devices. It is used when DC power is needed.

Among such batteries, a primary battery and a secondary battery, which are chemical cells using chemical reactions, are generally used. The primary battery is a consumable battery, which is commonly referred to as a battery. In addition, the secondary battery is a rechargeable battery manufactured using a material that can be repeated a number of redox process between the current and the material, the power is charged when the reduction reaction to the material by the current, the oxidation reaction to the material When performed, the power is discharged. As the charge-discharge is repeatedly performed, electricity is generated.

The method of manufacturing a lithium secondary battery has the advantage of ensuring safety and high energy efficiency because there is little risk of ignition or explosion because the electrolyte does not leak out even when the battery is damaged due to an accident.

In addition, there is no need to use a solid metal sheath, it can be manufactured in various sizes and shapes according to the application, it can be manufactured to a thickness of less than 3mm, weight can be reduced by more than 30%, mass production and large battery manufacturing is possible. .

For this reason, a method of manufacturing a lithium secondary battery is currently commercialized and used in various fields.

Korean Patent Laid-Open Publication No. 10-2008-0005631 discloses a stack and folding electrode assembly which prevents internal short circuits due to conventional heat shrinkage and an electrochemical cell including the same.

In the conventional laminated and folding secondary battery, since a bi-cell is stacked and folded on a separator, there is a difficulty in separately manufacturing a separator and a separator for folding the bi-cell.

Accordingly, the present invention has been made to solve the above difficulties, to provide an electrode assembly and a method for manufacturing an electrode assembly that can be used to assemble a secondary battery of a laminated and folded structure using a single separator.

The electrode assembly according to the present invention is developed to be foldable, and includes a separator member having a plurality of wings formed thereon, a first electrode stacked on the separator member, and the plurality of wings stacked and folded on the separator member. And a second electrode separated from the first electrode by a separator member.

The first electrode may be folded after being stacked on the separator member so as to be arranged in a row in a horizontal direction.

The second electrodes may be folded and stacked on the separator member such that a plurality of the second electrodes are arranged in a row in a horizontal direction so as to cross the first electrode.

The first first electrode closest to one end of the separator member among the plurality of first electrodes may be folded and spaced apart from the second electrodes stacked in a horizontal direction to intersect with the second first electrode. .

The first electrode or the second electrode that is farthest from one end in the folding direction of the separator member among the plurality of first electrodes or the second electrodes is horizontally spaced apart from the other end in the folding direction of the separator member. It may be folded.

One wing of one of the plurality of wings may be folded and stacked on the first electrode and the second electrode.

A second electrode may be stacked on the one wing portion stacked on the first electrode, and a first electrode may be stacked on the one wing portion stacked on the second electrode.

The other wing portion of the plurality of wing portions may be stacked on the first electrode and the second electrode stacked on the one wing portion.

A second electrode may be stacked on the other wing portion stacked on the first electrode, and a first electrode may be stacked on the other wing portion stacked on the second electrode.

The plurality of wings may be formed to face each other at both ends in the lateral direction of the folding member.

The first electrode and the second electrode may be stacked between the plurality of wing parts formed so as to face each other at both ends in a lateral direction of the separator member of the separator member.

The plurality of wings may be larger in size than the first electrode and the second electrode.

The plurality of wing portions may be formed with tab grooves cut through the electrode tabs of the first electrode and the second electrode.

In the electrode assembly manufacturing method according to the present invention, a separator cutting step of cutting a separator member to form a plurality of wings, a first electrode laminated step of stacking a plurality of first electrodes in a row so as to be arranged in a horizontal direction on the separator member, the A second electrode stacking step of stacking a plurality of second electrodes in a row such that the plurality of second electrodes are arranged in a horizontal direction so as to intersect the plurality of first electrodes on the separator member; the plurality of first electrodes and the plurality of stacked electrodes on the separator member A first wing folding step of folding and stacking one wing of the plurality of wings to each of the second electrode, the second electrode is laminated on the one wing respectively laminated on the plurality of first electrodes and the plurality of A first counter electrode stacking step of stacking a first electrode on the one wing part respectively stacked on two second electrodes, the one A second wing folding step of folding and stacking another wing part of the plurality of wing parts on the first electrode and the second electrode stacked on the open part, and a second on the other wing part stacked on the first electrode Stacking electrodes and stacking a second counter electrode stacking a first electrode on the other wing portion stacked on the second electrode and folding the separator member in one direction to vertically align the first electrode and the second electrode. It characterized in that it comprises a separator folding step of laminating so as to cross in the direction.

In addition, it may include a fixing step of fixing the membrane member folded in one direction using the end of the membrane member.

According to the present invention, there is an effect that both the stacking and folding of the electrode in one separator by cutting the wing to the separator member.

According to the present invention, as the electrode is laminated and folded with one separator, there is an effect of easily assembling the electrode assembly.

According to the present invention, there is no need to prepare a separate separator by stacking and folding electrodes with one separator, thereby simplifying the assembly process.

1 is a block diagram showing the development of a separator according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an electrode stacked on the separator of FIG. 1.
FIG. 3 is a diagram illustrating a configuration in which one of the plurality of wings is folded and stacked on the electrode of FIG. 2.
FIG. 4 is a configuration diagram illustrating an electrode laminated on one of the plurality of wing parts of FIG. 3.
FIG. 5 is a diagram illustrating a configuration in which the other wing part of the plurality of wing parts is folded and stacked on an electrode stacked on one wing part of the plurality of wing parts of FIG. 4.
FIG. 6 is a diagram illustrating an electrode laminated on a plurality of other wing parts of FIG. 5.
FIG. 7 is a view illustrating folding of the separator member of FIG. 6 in one direction.
FIG. 8 is a diagram illustrating the folding of the end of the separator member in FIG. 7.
9 is a flowchart sequentially illustrating a method of manufacturing an electrode assembly according to an exemplary embodiment of the present invention.

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

The terms or words used in this specification and claims are not to be construed as being limited to the common or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meanings and concepts 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 and variations.

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.

1 is a block diagram showing the development of a separator according to an embodiment of the present invention, Figure 2 is a block diagram showing the electrode laminated on the separator of Figure 1, Figure 3 is a plurality of electrodes of the electrode of FIG. FIG. 4 is a configuration diagram showing one wing part of the three wing parts folded and stacked, and FIG. 4 is a configuration diagram illustrating an electrode laminated on one wing part of the plurality of wing parts of FIG. 3.

As shown in Figures 1 to 4, the electrode assembly according to an embodiment of the present invention is developed to be foldable (folding), the membrane member 100, a plurality of wings 110 is formed, the membrane member The first electrode 10 stacked on the 100 and the separator member 100 are stacked on the separator 110 and separated from the first electrode 10 by the plurality of wings 110 and the separator member 100 that are folded. It includes a second electrode 20 to be.

As shown in FIG. 1, the membrane member 100 may include, for example, 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 any one substrate selected from the group consisting of a polymer).

The separation membrane member 100 is for separating the first electrode 10 and the second electrode 20.

The plurality of wings 110 are formed at opposite ends of the membrane member 100, respectively, and the pair of wings 110 formed at opposite ends of the membrane member 100 are positioned in a straight line to face each other. .

The first electrode 10 and the second electrode 20 may be an anode or a cathode of the electrode assembly, and the first electrode 10 and the second electrode 20 have different polarities.

That is, when the first electrode 10 is an anode, the second electrode 20 is made of a cathode. On the contrary, when the first electrode 10 is a cathode, the second electrode 20 is made of an anode.

The positive electrode may be an aluminum plate, and may include a positive electrode active material portion coated with a positive electrode active material and a positive electrode non-coated portion not coated with the positive electrode active material.

The positive electrode active material may be a lithium-containing transition metal oxide such as LiCoO 2, LiNiO 2, LiMnO 2, LiMnO 4, or a lithium chalcogenide compound.

For example, the positive electrode active material may be formed by applying a positive electrode active material to a portion of at least one surface of the aluminum plate, and the remaining portion of the aluminum plate not coated with the positive electrode active material may be a positive electrode non-coating portion.

The negative electrode may be a copper plate, and may include a negative electrode active material portion coated with a negative electrode active material and a negative electrode non-coated portion not coated with the negative electrode active material.

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

For example, the negative electrode active material portion may be formed by applying a negative electrode active material to at least a portion of at least one surface of the copper plate, and the remaining portion of the copper plate not coated with the negative electrode active material may be a negative electrode non-coating portion.

As illustrated in FIG. 2, the first electrodes 10 are stacked in a row along the surface of the separator member 100 on the separator member 100.

The second electrodes 20 are stacked in a row along the surface of the separator member 100 such that the second electrodes 20 intersect between the plurality of first electrodes 10 stacked on the separator member 100. do.

In this case, the first electrode 10 and the second electrode 20 are stacked between the pair of wing parts 110 formed on both sides of the membrane member 100. Here, the wing 110 may have a shape protruding outward on the same plane (vertical direction) with respect to the folding direction (horizontal direction) of the membrane member 100.

As shown in FIG. 3, each of the plurality of first electrodes 10 and the plurality of second electrodes 20 stacked on the separator member 100 includes one wing portion 110a of the plurality of wing portions 110. Is stacked in the direction of the arrow of FIG. That is, the wing 110 is folded and stacked on the electrode.

In this case, one wing portion 110a of the plurality of wing portions 110 is positioned at a portion where electrode tabs T of each of the plurality of first electrodes 10 and the plurality of second electrodes 20 are formed. The tab groove 111 through which the electrode tab T can penetrate is formed so that the electrode tab T does not interfere with the folding of the wing 110 when the 110 is folded.

The tab groove 111 is formed by partially cutting the boundary between the wing 110a of the plurality of wing portions 110 and the separator member 100, and the electrodes of the first electrode 10 and the second electrode 20. The position corresponding to the tap T is cut off.

As shown in FIG. 4, a second electrode 20 is stacked on one wing portion 110a of the plurality of wing portions 110 stacked on the plurality of first electrodes 10, and a plurality of second electrodes ( The first electrode 10 is stacked on one wing portion 110a of the plurality of wing portions 110 stacked on 20.

That is, the first electrode 10 and the second electrode 20 are stacked to cross each other with the wing portion 110a interposed therebetween, so that the first electrode 10 and the second electrode 20 are formed by the wing portion 110a. Are separated from each other.

In this case, the plurality of wing parts 110 may be stacked between the first electrode 10 and the second electrode 20 so that the first electrode 10 may be sufficiently separated from the first electrode 10 and the second electrode 20. The size is larger than that of the 10 and the second electrode 10.

FIG. 5 is a diagram illustrating a configuration in which another wing part of the plurality of wing parts is folded and stacked on an electrode stacked on one wing part of the plurality of wing parts of FIG. 4.

As illustrated in FIG. 5, the first electrode 10 and the second electrode 20 stacked on one wing 110a of the plurality of wing parts 110 are respectively different from the plurality of wing parts 110. One wing 110b is folded and stacked in the direction of the arrow of FIG. 5.

Here, one wing portion 110a of the plurality of wing portions 110 is a wing portion formed in one row along one end of the plurality of wing portions 110 formed to face each other at both ends of the membrane member 100, The other wing portion 110b of the inner part 110 is separated from the membrane member 100 so as to face the one wing portion 110a of the plurality of wing portions 110 formed to face each other at both ends of the membrane member 100. Along the other end of the wings are formed in a row.

FIG. 6 is a diagram illustrating an electrode laminated on a plurality of other wing parts of FIG. 5.

As shown in FIG. 6, a second electrode 20 is stacked on the other wing 110b stacked on the first electrode 10, and the other wing is stacked on the second electrode 20. The first electrode 10 is stacked on the unit 110b.

As described above, the first electrode 10 and the second electrode 20 are separated from each other by the plurality of wing parts 110 and are stacked on the separator member 100 to form a plurality of unit cells 120.

FIG. 7 is a view illustrating folding of the separator member of FIG. 6 in one direction.

As shown in FIG. 7, the plurality of unit cells 120 fold the separator member 100 to one side, and the first electrode 10 and the second electrode 20 forming the plurality of unit cells 120 are mutually different. The plurality of unit cells 120 are stacked while being separated from each other by the membrane member 100 and the wing 110.

2 to 6, the first first electrode (closest to one end of the separator member 100 in which the separator member 100 starts folding to one side among the plurality of first electrodes 10) 10 is spaced apart from the second electrode 20 stacked on the separator member 100 so as to intersect with the second first electrode 10.

That is, the plurality of first electrodes 10 and the plurality of second electrodes 20 stacked on the separator member 100 so as to cross each other form the unit cell 120 and then fold the separator member 100 to one side. Stacked to cross each other.

However, as shown in FIG. 6, in the process of folding the membrane member 100 in one direction so that the plurality of unit cells 120 are stacked on each other, the first one positioned closest to one end of the folding of the membrane member 100 is started. When the unit cell 120 and the second unit cell 120 closest to the first unit cell 120 are not spaced more than a predetermined interval, it is difficult to fold the membrane member 100 to one side.

Therefore, the first first electrode 10 closest to one end of the separator member 100 where the folding of the separator member 100 is started among the plurality of first electrodes 10 is the second stacked on the separator member 100. The electrode 20 is spaced apart from the first electrode 10 and the closest second electrode 20.

In addition, the separator member 100 is separated from the first electrode 10 or the second electrode 20 so that the separator member 100 is folded to one side, and thus the separator member 100 is stacked with each other. The other end of the 100 is folded to the other side (the direction opposite to the direction in which the separation membrane member 100 is folded) and attached to the unit cell 120 stacked on the uppermost layer so that the electrode assembly is fastened in the folded state.

FIG. 8 is a diagram illustrating the folding of the end of the separator member in FIG. 7.

As shown in FIG. 8, when the folding of the membrane member 100 is completed, an electrode assembly in which a plurality of unit cells 120 are stacked is assembled.

9 is a flowchart sequentially illustrating a method of manufacturing an electrode assembly according to an exemplary embodiment of the present invention.

1 to 9 will be described in detail an electrode assembly manufacturing method according to an embodiment of the present invention.

1 to 9, the electrode assembly manufacturing method according to an embodiment of the present invention is a separator cutting step (S1), the first electrode stacking step (S2), the second electrode stacking step (S3), A first wing folding step S4, a first counter electrode stacking step S5, a second wing folding step S6, a second counter electrode stacking step S7, and a separator folding step S8 are included.

As shown in FIG. 1 and FIG. 9, the separator cutting step (S1) is a step of cutting the separator member 100 to form a plurality of wings 110 at opposite ends of the separator member 100. Here, the separation membrane cutting step (S1) may be formed so as to project the plurality of wings 110 to the outside (vertical direction) on the same plane with respect to the folding direction (horizontal direction) of the separation membrane member 100.

The plurality of wing parts 110 are formed in plural numbers so as to form a pair while facing each other with respect to the separation membrane member 100.

And the plurality of wings 110 is formed larger in size than the electrode.

2 and 9, the first electrode stacking step S2 is a step of stacking a plurality of first electrodes 10 having one polarity among a plurality of electrodes along the separator member 100 in a row. to be.

The second electrode stacking step (S3) is polarized with the first electrode 10 to intersect the plurality of first electrodes 10 between the plurality of first electrodes 10 stacked in a row along the separator member 100. The second plurality of second electrodes 20 are stacked in a row along the membrane member 100.

As shown in FIGS. 3 and 9, the first wing folding step S4 may be performed by folding one wing part 110a formed in a row along one end of the membrane member 100 among the plurality of wing parts 110. By laminating to the plurality of first electrodes 10 and the plurality of second electrodes 20 stacked on the separator member 100.

As shown in FIGS. 4 and 9, in the stacking of the first counter electrode S5, the second electrode 20 is stacked on one wing part 110a respectively stacked on the plurality of first electrodes 10. The first electrode 10 is stacked on one wing 110a stacked on the plurality of second electrodes 20.

As illustrated in FIGS. 5 and 9, the second wing folding step S6 may include a plurality of wing parts formed on the first electrode 10 and the second electrode 20 stacked on one wing part 110a. Folding and stacking the other wing portion 110b formed to face the one wing portion 110a of the 110.

As shown in FIGS. 6 and 9, in the stacking of the second counter electrode S7, the second electrode 20 is stacked on the other wing 110b stacked on the first electrode 10, and the second electrode 20 is stacked. The first electrode 10 is stacked on the other wing part 110b stacked on the electrode 20.

As described above, the first electrode 10 and the second electrode 20 are separated from each other by using the wing unit 110, and thus, the plurality of unit cells are formed in the separator member 100 by forming the plurality of unit cells 120. Allow 120 to be stacked in one row.

As shown in FIG. 7 and FIG. 9, the separator folding step S8 may be performed by folding the separator member 100 to one side so that a plurality of unit cells 120 stacked in a row on the separator member 100 are separated from each other and stacked. This is the step.

8 and 9, after folding the membrane member 100 in one direction, the end of the membrane member 100 is folded in the opposite direction in which the membrane member 100 is folded to fold the unit cell positioned on the uppermost layer. In accordance with the attachment to 120 may further comprise a fixing step (S9) for fixing the folded membrane member 100.

According to the present invention as described above, there is an effect that both the stacking and folding of the electrode with one separator by cutting the wing portion to the separator member.

According to the present invention, as the electrode is laminated and folded with one separator, there is an effect of easily assembling the electrode assembly.

According to the present invention, there is no need to prepare a separate separator by stacking and folding electrodes with one separator, thereby simplifying the assembly process.

As described above, the electrode assembly and the method of manufacturing the electrode assembly according to the present invention have been described with reference to the illustrated drawings, but the present invention is not limited to the embodiments and drawings described above, and the present invention belongs to the claims. Many modifications and variations are possible to those skilled in the art.

10: first electrode
20: second electrode
100: membrane member
110: wing
110a: one wing
110b: another wing
111: tap groove
120: unit cell
T: tab

Claims (15)

A separator member 100 that is deployed to be foldable and has a plurality of wings 110 formed therein;
A first electrode 10 stacked on the separator member 100; And
A second electrode 20 stacked on the separator member 100 and separated from the first electrode 10 by the plurality of wing parts 110 and the separator member 100 that are folded; Including,
The plurality of wing parts 110 protruding vertically outwardly on the same plane with respect to the folding direction of the separator member 100 are folded and stacked on the first electrode 10 and the second electrode 20. Electrode assembly. The method according to claim 1,
The first electrode (10) is an electrode assembly, characterized in that the folded after being stacked in a plurality of rows arranged in the horizontal direction in the separator member (100). The method according to claim 2,
The second electrode (20) is an electrode assembly, characterized in that the plurality of stacked in the horizontal direction arranged in a row to cross the first electrode (10) on the membrane member 100 and then folded. The method according to claim 3,
The first first electrode 10 closest to one end of the separator member 100 among the plurality of first electrodes 10 is arranged in a horizontal direction so as to intersect with the second first electrode 10. Electrode assembly, characterized in that folded and spaced apart from the second electrode (20). The method according to claim 3,
Among the plurality of first electrodes 10 or the second electrodes 20, the first electrode 10 or the second electrode 20 farthest from the one end in the folding direction of the separator member 100 may be the separator. Electrode assembly, characterized in that the folding direction is spaced apart from the other end in the folding direction of the member 100 in the horizontal direction. delete The method according to claim 1,
One wing portion 110a of the plurality of wing portions 110 is folded and stacked on the first electrode 10 and the second electrode 20,
A second electrode 20 is stacked on the one wing portion 110a stacked on the first electrode 10, and a first electrode is placed on the one wing portion 110a stacked on the second electrode 20. Electrode assembly, characterized in that the stack (10). The method according to claim 7,
The first electrode 10 and the second electrode 20 stacked on the one wing portion 110a is characterized in that the other wing portion 110b of the plurality of wing portions 110 is stacked. Electrode assembly. The method according to claim 8,
A second electrode 20 is stacked on the other wing portion 110b stacked on the first electrode 10, and a second electrode 20 is stacked on the other wing portion 110b stacked on the second electrode 20. Electrode assembly, characterized in that the electrode 10 is laminated. The method according to claim 1,
The plurality of wing parts 110 is formed to face each other at both ends in the lateral direction of the folding direction of the membrane member (100). The method according to claim 10,
The plurality of wings 110 formed to face each other at both ends of the first electrode 10 and the second electrode 20 in the lateral direction of the separator member 100 in the folding direction of the separator member 100. Electrode assembly, characterized in that laminated between. The method according to claim 1,
The plurality of wings 110 is an electrode assembly, characterized in that the size is larger than the first electrode (10) and the second electrode (20). The method according to claim 1,
The plurality of wing parts (110) is an electrode assembly, characterized in that the tab groove 111 is formed to be cut through the electrode tab (T) of the first electrode (10) and the second electrode (20). Separating membrane cutting step (S1) to form a plurality of wings to protrude to the vertical outward on the same plane with respect to the folding direction of the membrane member by cutting the membrane member;
Stacking the first electrodes in a row such that the plurality of first electrodes are arranged in the horizontal direction on the separator member (S2);
A second electrode stacking step (S3) of stacking the plurality of second electrodes in a row such that the plurality of second electrodes are arranged in a horizontal direction so as to cross the plurality of first electrodes on the separator member;
A first wing folding step (S4) of folding and laminating one wing of the plurality of wings to each of the plurality of first electrodes and the plurality of second electrodes stacked so as to be arranged in a horizontal direction on the separator member. ;
Stacking a first counter electrode to stack a second electrode on the one wing part respectively stacked on the plurality of first electrodes and a first electrode on the one wing part respectively stacked on the plurality of second electrodes (S5);
A second wing folding step (S6) of folding and stacking another wing of the plurality of wings to the first electrode and the second electrode stacked on the one wing;
A second counter electrode stacking step (S7) of stacking a second electrode on the other wing portion stacked on the first electrode and a first electrode on the other wing portion stacked on the second electrode; And
A separator folding step (S8) of folding the separator member in one direction to stack the first electrode and the second electrode in a vertical direction; Electrode assembly manufacturing method comprising a. The method according to claim 14,
The electrode assembly manufacturing method characterized in that it further comprises a fixing step (S9) for fixing the membrane member folded in one direction using the end of the membrane member.

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