阅读说明：本技术 用于二次电池的冲切装置和方法 (Punching device and method for secondary battery ) 是由 李秉揆 具滋训 表廷官 金津坤 郑太轸 金元年 于 2019-04-01 设计创作，主要内容包括：本发明包括一种用于二次电池的冲切装置。所述冲切装置包括：包括冲模和冲模保持器的下部机构,设有涂覆部分和未涂覆部分的电极设置在冲模上,所述冲模固定到所述冲模保持器；脱模器,包括按压涂覆部分的第一脱模器和按压及固定未涂覆部分的一对第二脱模器；包括冲头和冲头保持器的上部机构,冲头设在一对第二脱模器之间且设有切割刀片,所述切割刀片切割设置在一对第二脱模器之间的未涂覆部分,所述冲头保持器允许冲头在下部机构的方向上移动；及按压构件,在所述未涂覆部分被所述冲头切割时,所述按压构件按压设置在一对第二脱模器之间的未涂覆部分,以增加所述未涂覆部分的张力。(The present invention includes a die-cutting device for a secondary battery. The die-cutting device includes: a lower mechanism including a die on which an electrode provided with a coated portion and an uncoated portion is disposed and a die holder to which the die is fixed; a stripper including a first stripper pressing the coated portion and a pair of second strippers pressing and fixing the uncoated portion; an upper mechanism including a punch provided between the pair of second strippers and provided with a cutting blade that cuts an uncoated portion provided between the pair of second strippers, and a punch holder that allows the punch to move in a direction of the lower mechanism; and a pressing member that presses an uncoated portion provided between the pair of second strippers to increase a tension of the uncoated portion when the uncoated portion is cut by the punch.)

1. A punching device for a secondary battery, comprising:

a lower mechanism including a die on which an electrode is provided, the electrode being provided with a coated portion coated with an electrode active material and an uncoated portion uncoated with the electrode active material, and a die holder to which the die is fixed;

a stripper including a first stripper disposed above a coated portion disposed on the lower mechanism to press the coated portion while descending toward the coated portion, and a pair of second strippers disposed above an uncoated portion disposed on the lower mechanism to press and fix the uncoated portion while descending toward the uncoated portion;

an upper mechanism including a punch provided between the pair of second strippers and provided with a cutting blade that cuts the uncoated portion provided between the pair of second strippers, and a punch holder that fixes the punch to allow the punch to move in a direction of the lower mechanism; and

a pressing member that presses the uncoated portion disposed between the pair of second strippers to increase a tension of the uncoated portion when the uncoated portion is cut by the punch.

2. The die cutting device according to claim 1, wherein the pressing member is provided on a bottom surface of the punch and protrudes further downward than the cutting blade when viewed from a surface of the uncoated portion.

3. The punching device according to claim 1, wherein the pressing member is integrally provided on a bottom surface of the punch or detachably provided on the bottom surface of the punch.

4. The die-cutting device according to claim 1, wherein a pressing surface of the pressing member that presses the uncoated portion is provided as a horizontal surface.

5. The die-cutting device according to claim 1, wherein the pressing member is made of synthetic resin having elasticity.

6. The die-cutting device according to claim 1, wherein the first ejector is provided on the punch holder corresponding to the coated portion to press the coated portion when being lowered by the punch holder.

7. A blanking device according to claim 6, wherein the first stripper is mounted on the punch holder so as to be adjustable in length in the direction of the lower mechanism or in the opposite direction.

8. The die cutting device according to claim 1, wherein the second ejector is provided on the punch holder corresponding to the uncoated portion to press the uncoated portion.

9. A blanking unit according to claim 8, wherein each of the second strippers is mounted to be adjustable in length in the direction of the lower mechanism or in the opposite direction.

10. The die cutting device of claim 1, wherein the uncoated portion includes a connecting surface connected to the coated portion and an uncoated surface extending from the connecting surface, and

the second stripper presses the uncoated surface to fix the uncoated surface to the die.

11. The die cutting device according to claim 10, wherein the punch sequentially cuts the connecting surface and the uncoated surface provided between the pair of second strippers.

12. The die cutting device of claim 11, wherein the second ejector presses the uncoated surface without securing the uncoated surface to the lower mechanism while the punch cuts the connecting surface.

13. The die cutting device of claim 12, wherein the second ejector presses the uncoated surface to secure the uncoated surface to the lower mechanism while the punch cuts the uncoated surface.

14. A die cutting method for a secondary battery, comprising:

a step (a) of disposing an electrode on the die of the lower mechanism, the electrode being provided with a coated portion coated with an electrode active material and an uncoated portion not coated with the electrode active material;

a step (b) of pressing and fixing the coated portion of the electrode provided on the die using a first ejector of the ejectors;

a step (c) of pressing the uncoated portion of the electrode disposed on the die using a second ejector of the ejectors, wherein the second ejector is provided as a pair of second ejectors, the uncoated portion includes a connecting surface connected with the coated portion and an uncoated surface extending from the connecting surface, and the pair of second ejectors primarily presses the uncoated surface of the uncoated portion without fixing the uncoated surface to the lower mechanism;

a step (d) of pressing the uncoated portion disposed between the pair of second strippers with a pressing member to increase the tension of the uncoated portion;

a step (e) of cutting the connecting surface of the uncoated portion increased in tension using a punch of an upper mechanism;

a step (f) of pressing the uncoated surface of the uncoated portion a second time using the second ejector upon completion of the cutting of the connecting surface so as to fix the uncoated surface to the lower mechanism; and

step (g) of cutting the uncoated surface using the punch of the upper mechanism when the uncoated surface is completely fixed.

15. The die cutting method according to claim 14, wherein in step (d), the pressing member presses the uncoated surface of the uncoated portion to increase the tension.

Technical Field

The present invention relates to a punching apparatus and method for a secondary battery that cuts an uncoated portion in an electrode, and more particularly, to a punching apparatus and method for a secondary battery that increases the tension of an uncoated portion when cutting the uncoated portion to improve the cutting accuracy.

Background

In general, a secondary battery refers to a chargeable and dischargeable battery, unlike a non-chargeable primary battery. Secondary batteries are being widely used in high-tech electronic fields such as mobile phones, notebook computers, and video cameras.

Such secondary batteries are classified into can type secondary batteries in which an electrode assembly is built in a metal can and pouch type secondary batteries in which an electrode assembly is built in a pouch. The pouch-type secondary battery includes an electrode assembly, an electrolyte, and a pouch accommodating the electrode assembly and the electrolyte. In addition, the electrode assembly has a structure in which a plurality of electrodes and a plurality of separators are alternately stacked.

The electrode includes a coated portion coated with an electrode active material and an uncoated portion uncoated with the electrode active material. In the electrode having such a configuration, the uncoated portion is cut by a punching device to form the electrode tab.

That is, the die-cutting device includes: a lower plate on which the die is mounted, the electrode being disposed on the die; a stripper which fixes the electrode provided on the die; and an upper plate on which a punch for cutting an uncoated portion of the electrode disposed on the die is mounted.

However, in the die-cutting device, although the coated portion is fixed by the ejector, there is a problem that the uncoated portion is not fixed due to the thickness of the coated portion. In particular, in the die-cutting device, when cutting an unfixed uncoated portion, there is a problem in that a surface to be cut is irregularly cut due to a moving phenomenon of the uncoated portion.

Disclosure of Invention

Technical problem

The present invention has been developed to solve the above-described problems, and an object of the present invention is to provide a die-cutting device and method in which each of a coated portion and an uncoated portion in an electrode is pressed to enhance a fixing force of the coated portion and the uncoated portion, and particularly, when the uncoated portion is cut, a tension of the uncoated portion is increased to improve cutting accuracy.

Technical scheme

In order to achieve the above object, a punching device for a secondary battery according to a first embodiment of the present invention includes: a lower mechanism including a die on which an electrode is provided, the electrode being provided with a coated portion coated with an electrode active material and an uncoated portion uncoated with the electrode active material, and a die holder to which the die is fixed; a stripper including a first stripper disposed above a coated portion disposed on the lower mechanism to press the coated portion while descending toward the coated portion, and a pair of second strippers disposed above an uncoated portion disposed on the lower mechanism to press and fix the uncoated portion while descending toward the uncoated portion; an upper mechanism including a punch provided between the pair of second strippers and provided with a cutting blade that cuts the uncoated portion provided between the pair of second strippers, and a punch holder that fixes the punch to allow the punch to move in a direction of the lower mechanism; and a pressing member that presses the uncoated portion disposed between the pair of second strippers to increase a tension of the uncoated portion when the uncoated portion is cut by the punch.

The pressing member may be provided on a bottom surface of the punch and protrude further downward than the cutting blade when viewed from a surface of the uncoated portion.

The pressing member may be integrally provided on the bottom surface of the punch or detachably provided on the bottom surface of the punch.

A pressing surface of the pressing member that presses the uncoated portion may be provided as a horizontal surface.

The pressing member may be made of synthetic resin having elasticity.

The first ejector may be mounted on the punch holder corresponding to the coating portion to press the coating portion when being lowered by the punch holder.

The first ejector may be provided on the punch holder so that the length is adjustable in the direction of the lower mechanism or in the opposite direction.

The second ejector may be provided on the punch holder corresponding to the uncoated portion to press the uncoated portion.

Each of the second strippers may be installed to be adjustable in length in the direction of the lower mechanism or in the opposite direction.

The uncoated portion may include a connecting surface connected with the coated portion and an uncoated surface extending from the connecting surface, and the second ejector may press the uncoated surface to fix the uncoated surface to the die.

The punch may sequentially cut the connecting surface and the uncoated surface provided between the pair of second strippers.

The second ejector may press the uncoated surface without fixing the uncoated surface to the lower mechanism while the punch cuts the connection surface.

The second ejector may press the uncoated surface so as to fix the uncoated surface to the lower mechanism while the punch cuts the uncoated surface.

In order to achieve the above object, a punching method for a secondary battery according to a first embodiment of the present invention includes: a step (a) of disposing an electrode on the die of the lower mechanism, the electrode being provided with a coated portion coated with an electrode active material and an uncoated portion uncoated with the electrode active material; a step (b) of pressing and fixing the coated portion of the electrode provided on the die using a first ejector of the ejectors; a step (c) of pressing the uncoated portion of the electrode disposed on the die using a second ejector of the ejectors, wherein the second ejector is provided as a pair of second ejectors, the uncoated portion includes a connecting surface connected with the coated portion and an uncoated surface extending from the connecting surface, and the pair of second ejectors primarily presses the uncoated surface of the uncoated portion without fixing the uncoated surface to the lower mechanism; a step (d) of pressing the uncoated portion disposed between the pair of second strippers with a pressing member to increase the tension of the uncoated portion; a step (e) of cutting the connecting surface of the uncoated portion increased in tension using a punch of an upper mechanism; a step (f) of pressing the uncoated surface of the uncoated portion a second time using the second ejector upon completion of the cutting of the connecting surface so as to fix the uncoated surface to the lower mechanism; and (g) cutting the uncoated surface using the punch of the upper mechanism when the uncoated surface is completely fixed.

In the step (d), the pressing member may press the uncoated surface of the uncoated part to increase tension.

Advantageous effects

1. According to the present invention, there is provided a stripper provided with a first stripper fixing a coated portion of an electrode and a second stripper fixing an uncoated portion of the electrode. Thus, the coated portion and the uncoated portion of the electrode can be pressed and fixed. Therefore, when cutting the uncoated part, the surface to be cut of the uncoated part can be prevented from being irregularly cut to improve cutting accuracy.

In particular, a pressing member that presses the uncoated portion to increase tension when cutting the uncoated portion may be provided to prevent wrinkles from occurring on the uncoated portion, thereby improving cutting accuracy of the uncoated portion.

2. According to the present invention, the pressing member may protrude more downward than the cutting blade when viewed from the surface of the uncoated portion. Therefore, the uncoated portion can be cut without generating wrinkles on the uncoated portion to improve cutting accuracy of the uncoated portion.

3. According to the present invention, the pressing member may be integrally or detachably provided on the bottom surface of the punch. That is, the pressing member and the punch may be integrally provided for easy manufacturing. In addition, the pressing member may be detachably provided on the punch. Therefore, pressing members having various sizes may be installed according to the size of the electrode to improve compatibility.

4. According to the present invention, the pressing surface of the pressing member that presses the uncoated portion may be provided as a horizontal surface. That is, the adhesion between the pressing member and the uncoated portion may be increased to prevent the uncoated portion from being damaged by the pressing member, and particularly, the uncoated portion may be stably pressed to prevent wrinkles from occurring on the uncoated portion.

5. According to the present invention, when the pressing member is detachably provided on the punch, the pressing member may be made of synthetic resin having elasticity. Therefore, the uncoated portion can be prevented from being excessively pressed by the pressing member to prevent damage to the uncoated portion.

6. According to the present invention, the first ejector may be provided on a punch holder including a punch to press the coating portion when being lowered by the punch holder. Therefore, the first ejector can be easily installed. In particular, the first ejector may be lowered together with the punch when the punch holder is lowered. As a result, the coated portion can be fixed, and the uncoated portion can be cut only by the descent of the punch holder.

7. According to the invention, the first stripper can be mounted on the punch holder so that the length towards the electrode can be adjusted. Therefore, the coated portions of the electrodes having different thicknesses can be effectively fixed, and the pressing force applied to the coated portions of the electrodes can be adjusted.

8. According to the present invention, the second ejector may be provided as a pair, and the pair of second ejectors may be mounted on the punch holder corresponding to the uncoated portion. Therefore, the second ejector can be easily installed. In particular, the second ejector may be lowered together with the punch when the punch holder is lowered. As a result, the uncoated portion can be fixed and cut only by the lowering of the punch holder. In particular, a pair of second strippers may be provided on both sides of the punch. Therefore, the uncoated portion can be cut more stably.

9. According to the invention, a second stripper can be mounted on the punch holder so that the length towards the electrode can be adjusted. Therefore, the uncoated portions of the electrodes having different thicknesses can be effectively fixed, and the pressing force applied to the uncoated portions of the electrodes can be adjusted.

10. According to the present invention, the uncoated portion has a connecting surface connected with the coated portion and an uncoated surface connected with the connecting surface, and the second ejector can press the uncoated surface of the uncoated portion. Therefore, the uncoated portion can be stably fixed without having wrinkles.

11. According to the present invention, the second ejector may press the uncoated surface without fixing the uncoated surface while the punch cuts the connecting surface of the uncoated portion. Therefore, the punch can stably cut the connection surface of the unfixed uncoated surface to improve the cutting quality.

12. According to the present invention, the second ejector may press the uncoated surface while fixing the uncoated surface when cutting the uncoated surface of the uncoated portion. Therefore, the punch can stably cut the uncoated surface of the uncoated portion to improve the cutting quality.

Drawings

Fig. 1 is a perspective view of a punching device for a secondary battery according to a first embodiment of the present invention.

Fig. 2 is a front view of a punching apparatus for a secondary battery according to a first embodiment of the present invention.

Fig. 3 is a side view of a punching apparatus for a secondary battery according to a first embodiment of the present invention.

Fig. 4 is a sectional view taken along line C-C of fig. 1.

Fig. 5 is a front view showing a pressed state of the pressing member according to the first embodiment of the present invention.

Fig. 6 is a side view showing a pressed state of the first and second strippers according to the first embodiment of the invention.

Fig. 7 is a process diagram of a punching method for a secondary battery according to a first embodiment of the present invention.

Fig. 8 is a schematic side view illustrating step (a) of the punching method for a secondary battery according to the first embodiment of the present invention.

Fig. 9 is a schematic side view showing step (b) of the punching method for a secondary battery according to the first embodiment of the present invention.

Fig. 10 is a schematic side view illustrating step (c) of the punching method for a secondary battery according to the first embodiment of the present invention.

Fig. 11 is a schematic front view showing step (d) of the die-cutting method for a secondary battery according to the first embodiment of the present invention.

Fig. 12 is a schematic side view showing step (e) of the punching method for a secondary battery according to the first embodiment of the present invention.

Fig. 13 is a schematic side view showing step (e) and step (f) of the punching method for a secondary battery according to the first embodiment of the present invention.

Fig. 14 is a sectional view of a punching device for a secondary battery according to a second embodiment of the present invention.

Fig. 15 is a perspective view showing another example of the punching device for a secondary battery according to the first embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings in such a manner that a person having ordinary skill in the art to which the present invention pertains can easily carry out the technical idea of the present invention. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, anything not necessary to describe the present invention will be omitted for clarity, and like reference numerals denote like elements throughout the drawings.

In the drawings, the front view is a view when viewed in the direction "a" of fig. 1, and the side view is a view when viewed in the direction "B" of fig. 1.

[ electrodes ]

Referring to fig. 6, the electrode 10 includes a coated portion 11 coated with an electrode active material and an uncoated portion 12 uncoated with the electrode active material. The uncoated portion 12 includes a connecting surface 12a connected with the coated portion 11 and an uncoated surface 12b extending from the connecting surface 12 a.

The uncoated portion 12 of the electrode 10 having the above-described configuration is processed into an electrode tab by cutting the uncoated portion 12. Here, the punching apparatus for a secondary battery according to the present invention is used.

In particular, the punching device for a secondary battery according to the present invention may have a structure in which, when cutting the uncoated portion, the uncoated portion is cut without forming wrinkles on the connection surface to improve the cutting quality.

Hereinafter, a punching apparatus for a secondary battery according to an embodiment of the present invention will be described.

[ punching device for secondary battery according to first embodiment of the invention ]

As shown in fig. 1 to 5, the die-cutting device 100 to be processed into an uncoated portion of an electrode tab in a cutting electrode according to a first embodiment of the present invention includes: a lower mechanism 110 on which the electrode 10 is disposed; a stripper 120 that fixes the electrode 10 provided on the lower mechanism 110; cutting the upper mechanism 130 fixed to the uncoated portion 12 of the ejector 120; and a pressing member 140, the pressing member 140 increasing the tension of the uncoated portion 12 by pressing the uncoated portion 12 with the upper member 130 when the uncoated portion 12 is cut.

Lower mechanism

The lower mechanism 110 may be configured to mount an electrode thereon and include a die 111 and a die holder 112, the electrode 10 constituted by the coated portion 11 and the uncoated portion 12 being disposed on the die 111, the die 111 being fixed to the die holder 112. An insertion groove 111a on which the uncoated portion 12 is disposed may be formed in the surface of the die 111, and a punch cutting the uncoated portion may be inserted into the insertion groove 111a to effectively cut the uncoated portion.

Demoulding device

The ejector may press each of the coated portion and the uncoated portion provided on the die to fix each of the coated portion and the uncoated portion. Therefore, when the uncoated portion is cut, the uncoated portion can be prevented from moving to improve the cutting quality of the uncoated portion.

For example, as shown in fig. 2 to 4, the ejector 120 includes a first ejector 121 and a second ejector 122, the first ejector 121 being disposed above the coated portion 11 placed on the lower mechanism 110 to press and fix the coated portion 11 while descending toward the coated portion 11, and the second ejector 122 being disposed above the uncoated portion 12 placed on the lower mechanism 110 to press and fix the uncoated portion 12 while descending toward the uncoated portion 12.

That is, the ejector 120 includes a first ejector 121 and a second ejector 122. The first and second strippers 121 and 122 may press the coated and uncoated portions 11 and 12 of the electrode 10 to fix the coated and uncoated portions 11 and 12, respectively. That is, the first ejector 121 may press and fix the coated portion 11, and the second ejector 122 may press and fix the uncoated portion 12. Therefore, both the coated portion 11 and the uncoated portion 12 can be securely fixed. In particular, the non-coating portion can be stably fixed regardless of the height deviation between the coating portion 11 and the non-coating portion 12 to improve cutting accuracy when cutting the non-coating portion 12.

Upper mechanism

The upper mechanism may be configured to cut an uncoated portion of the electrode held by the ejector. The upper mechanism includes a punch 131 and a punch holder 132, the punch 131 cutting the uncoated portion 12 of the electrode 10 fixed by the ejector 120, the punch holder 132 fixing the punch 131 to allow the punch 131 to move toward the lower mechanism 110.

That is, when the punch holder 132 is lowered toward the lower mechanism 110, the upper mechanism 130 cuts the uncoated portion 12 of the electrode 10 fixed by the ejector 120 while being lowered together with the punch holder 132.

Referring to fig. 1, a first ejector 121 is mounted on a punch holder 132 corresponding to the coating portion 11 provided on the die 111 to press the coating portion 11 while being lowered by the punch holder 132.

That is, the first ejector 121 may be mounted on the punch holder 132. Therefore, when the punch holder 132 descends, the first ejector 121 can press the coating portion 11 while descending together with the punch holder 132. As a result, the structure of the first ejector 121 can be simplified to reduce the manufacturing cost.

Here, the first ejector 121 may be disposed closer to the electrode 10 disposed on the die 111 than the punch 131 mounted on the punch holder 132. That is, there is a height difference between the first ejector 121 and the punch 131, so that the punch 131 cuts the uncoated portion 12 of the electrode 10 after the first ejector 121 presses and fixes the coated portion 11 of the electrode 10 while the punch holder 132 descends. For example, as shown in fig. 2, the first ejector 121 and the punch 131 are mounted on the bottom surface of the punch holder 132. Here, the first ejector 121 is installed at a position lower than the punch 131 when viewed from the die.

As shown in fig. 4, the second strippers 122 are provided in a pair, and the punch 131 is provided between the pair of second strippers 122. That is, the pair of second strippers 122 press and fix both ends of the uncoated part 12, respectively, and the punch 131 cuts the uncoated part 12 disposed between the pair of second strippers 122. Therefore, the fixing force and the cutting force of the uncoated portion 12 can be increased at the same time.

Here, the punch 131 includes a cutting blade 131a on each of both ends thereof disposed near the pair of second strippers 122, the cutting blade 131a cutting each surface of the uncoated part 12 disposed near the pair of second strippers 122.

The second ejector 122 is mounted closer to the electrode 10 than the punch 131 when fixed to the punch holder 132. That is, there is a height difference between the second ejector 122 and the punch 131, so that the punch 131 cuts the uncoated portion 12 of the electrode 10 after the second ejector 122 presses the uncoated portion 12 of the electrode 10 while the punch holder 132 descends. For example, the second ejector 122 and the punch 131 are mounted on the bottom surface of the punch holder 132. Here, the second ejector 122 is installed at a position lower than the punch 131 when viewed from the die.

The bottom surface of the second ejector 122 has a height difference of 10 μm to 20 μm, particularly 15 μm, from the bottom surface of the punch 131. That is, when the uncoated surface 12b of the electrode 10 is pressed by the second ejector 122, the connecting surface 12a of the uncoated portion 12 may be bent. Here, the height difference between the uppermost end portion of the curved connecting surface 12a and the uncoated surface 12b is formed to be 10 μm or less. Therefore, the height difference between the bottom surface of the second ejector 122 and the bottom surface of the punch 131 is formed to be 10 μm to 20 μm, particularly, to be 15 μm. Therefore, in a state where the second ejector 122 presses the uncoated surface 12b without fixing the uncoated surface 12b, the punch 131 can cut the connecting surface 12a of the uncoated portion 12.

In summary, as shown in fig. 5, the first ejector 121, the second ejector 122, and the punch 131 are mounted on the bottom surface of the punch holder 132. Here, the first ejector 121 is mounted so as to be disposed at the lowermost end portion when seen in fig. 2, the second ejector 122 is mounted so as to be disposed at the intermediate portion when seen in fig. 2, and the punch 131 is mounted so as to be disposed at the uppermost end portion when seen in fig. 2. Due to the above configuration, when the punch holder 132 is lowered, the first ejector 121 presses the coating portion 11 of the electrode 10. Then, the second ejector 122 presses the uncoated portion 12 of the electrode 10 without fixing the uncoated portion 12, and then, the punch 131 cuts the connecting surface of the uncoated portion 12 of the electrode 10.

The second ejector 122 presses the uncoated surface 12b of the uncoated portion 12 to fix the uncoated surface 12b to the die 111. That is, the connecting surface 12a of the non-coating portion 12 is connected to the coating portion 11. Therefore, when the connection surface 12a is pressed, the connection surface 12a can be bent at a right angle. Therefore, the second ejector 122 can press the uncoated surface 12b extending from the connecting surface 12a to stably press the uncoated portion 12.

The punch 131 sequentially cuts the connecting surface 12a and the uncoated surface 12b of the uncoated portion 12 disposed between the pair of second strippers 122. Here, the second ejector 122 presses the uncoated surface 12b to the die 111 of the lower mechanism 110 while the punch 131 cuts the connecting surface 12 a. That is, when the second ejector 122 presses the uncoated surface 12b to fix it to the die 111 of the lower mechanism 110, the connecting surface 12a of the uncoated portion 12 may wrinkle when bent. That is, the connecting surface 12a may be formed to be curved between the coated portion 11 and the uncoated surface 12 b. In this state, when the punch 131 cuts the connecting surface 12a, burrs may be formed on the cut surface of the connecting surface 12a, causing cutting defects. To avoid this phenomenon, when the punch 131 cuts the connecting surface 12a, the second ejector 122 may press the uncoated surface 12b without fixing the uncoated surface 12b to the die 111 of the lower mechanism 110 to prevent wrinkles from being formed on the connecting surface 12 a. In this state, the punch 131 cuts the connecting surface 12a to prevent burrs from being formed on the cut surface of the connecting surface 12a, thereby improving the cutting quality.

While the punch 131 cuts the uncoated surface 12b, the second ejector 122 presses the uncoated surface 12b to fix it to the die 111 of the lower mechanism 110. That is, the uncoated surface 12b is provided to closely adhere to the die 111. Therefore, even if the uncoated surface 12b is fixed, wrinkles are not formed on the uncoated surface 12 b. Therefore, when the punch 131 cuts the uncoated surface 12b, the second ejector 122 may press the uncoated surface 12b to fix it to the die 111 of the lower mechanism 110, thereby improving the cutting quality of the uncoated surface 12 b.

Pressing member

As shown in fig. 5, the pressing member 140 is configured to increase the tension of the uncoated portion disposed between the pair of second strippers. The pressing member 140 may press the uncoated part 12 to increase tension when the uncoated part 12 is cut by the punch 131, thereby effectively preventing wrinkles from being formed on the uncoated part 12 and improving cutting accuracy when the uncoated part 12 is cut by the punch 131.

Here, the pressing member 140 is provided on the bottom surface of the punch 131. Here, the pressing member 140 may protrude more downward (in the direction of the uncoated portion) than the cutting blade 131a when viewed from the surface of the uncoated portion 12. Accordingly, the pressing member 140 may press the uncoated portion to increase the tension before the cutting blade 131a cuts the uncoated portion 12. As a result, the uncoated portion 12 can be cut in a state where wrinkles are removed.

In particular, the pressing member 140 is disposed above the second ejector 122 when viewed from the surface of the uncoated portion 12. Accordingly, the second ejector 122 presses the uncoated portion 12, and then, the pressing member 140 presses the uncoated portion 12 to increase the tension of the uncoated portion 12.

In general, referring to fig. 2, the cutting blade 131a of the punch 131, the pressing member 140, the second ejector 122, and the first ejector 121 gradually protrude downward in sequence.

The pressing member 140 may be integrally provided on the bottom surface of the punch 131 or detachably provided on the bottom surface of the punch 131.

For example, as shown in fig. 1, the pressing member 140 is integrally provided on the bottom surface of the punch 131. That is, the pressing member 140 may be molded together with the punch 131 when the punch 131 is molded, to improve manufacturing simplicity.

As another example, as shown in fig. 15, the pressing member 140 is detachably provided on the bottom surface of the punch 131. That is, a coupling groove 131b is formed at the center of the bottom surface of the punch 131, and a coupling protrusion is formed on the pressing member 140 to be detachably coupled to the coupling groove 131 b. Accordingly, pressing members having different sizes may be selected according to the size of the electrode so as to be coupled to the punch 131, thereby improving ease of use and compatibility.

The pressing surface 141 of the pressing member 140 pressing the uncoated portion 12 may be provided as a horizontal surface to increase a contact area between the uncoated portion 12 and the pressing member 140. Therefore, the pressing force of the pressing member 140 can be uniformly dispersed to the contact area between the uncoated portion 12 and the pressing member 140 to effectively prevent the uncoated portion 12 from being damaged.

The pressing member 140 may be made of synthetic resin having elasticity. Therefore, the uncoated portion 12 can be elastically pressed by the pressing member 140 to effectively prevent damage to the uncoated portion 12.

The pressing member 140 presses the uncoated surface 12b provided on the uncoated portion 12 to increase the tension. That is, the connection surface 12a may be formed to be bent between the coated portion 11 and the uncoated surface 12 b. Therefore, when the pressing member 140 presses the connection surface 12a, the connection surface 12a may be buckled to cause a defect. Therefore, it is preferable that the pressing member 140 presses the uncoated surface 12b to increase the tension.

The punching device 100 for a secondary battery according to the first embodiment of the present invention having the above-described configuration includes the ejector 120 having the first ejector 121 and the second ejector 122. Therefore, the coated portion 11 and the uncoated portion 12 of the electrode 10 can be separately pressed and fixed. As a result, both the coated portion 11 and the uncoated portion 12 can be stably fixed. In particular, when the uncoated portion 12 is cut, the tension of the uncoated portion may be increased via the pressing member 140 to prevent wrinkles from being formed on the uncoated portion, thereby improving the cutting accuracy of the uncoated portion.

Hereinafter, a die-cutting method using the die-cutting device 100 according to the first embodiment of the present invention will be described.

[ punching method for secondary battery according to first embodiment of the invention ]

As shown in fig. 7, the die-cutting method for a secondary battery according to the first embodiment of the present invention includes a step (a) of providing an electrode, a step (b) of fixing a coated portion of the electrode, a step (c) of primarily pressing an uncoated portion of the electrode, a step (d) of adjusting the tension of the uncoated portion of the electrode, a step (e) of cutting a connection surface on the uncoated portion of the electrode, a step (f) of secondarily pressing the uncoated portion of the electrode so as to be fixed, and a step (g) of cutting the uncoated surface on the uncoated portion of the electrode.

As shown in fig. 8, in step (a), an electrode 10 composed of a coated portion 11 coated with an electrode active material and an uncoated portion 12 uncoated with the electrode active material is set on a die 111 of a lower mechanism 110. Here, the portion to be cut of the uncoated portion 12 is disposed in an insertion groove 111a formed in the die 111.

As shown in fig. 9, in step (b), the first ejector 121 of the ejector 120 is used to press and fix the coated portion 11 of the electrode 10 provided on the die 111 of the lower mechanism 110.

That is, when the punch holder 132 of the upper mechanism 130 is lowered, the ejector 120 including the first ejector 121 and the second ejector 122 mounted on the punch holder 132 is lowered together with the punch 131. Here, the first ejector 121 disposed at the lowermost end portion may first press and fix the coating portion 11 of the electrode 10.

As shown in fig. 10, in step (c), the uncoated portion 12 of the electrode 10 disposed on the die 111 of the lower mechanism 110 is pressed using the second ejector 122. Here, the second ejector 122 is provided as a pair. The uncoated portion 12 includes a connecting surface 12a connected with the coated portion 11 and an uncoated surface 12b extending from the connecting surface 12a, and the pair of second strippers 122 primarily presses the uncoated surface 12b of the uncoated portion 12 without fixing the uncoated surface 12b to the die 111.

That is, when the punch holder 132 is lowered again, the second ejector 122 is lowered together with the punch 131. therefore, the second ejector 122 disposed below the punch 131 presses the uncoated surface 12b of the uncoated portion 12. here, the second ejector 122 presses the uncoated surface 12b without fixing the uncoated surface 12b to the die 111. that is, as shown in the enlarged view of fig. 10, the uncoated surface 12b is movable because a gap α is formed between the uncoated surface 12b and the die 111. therefore, the connecting surface 12a formed between the coated portion 11 and the uncoated surface 12b may not be wrinkled by the restoring force.

As shown in fig. 11, in step (d), the uncoated surface 12b of the uncoated portion 12 disposed between the pair of second strippers 122 is pressed by the pressing member 140 to increase the tension of the uncoated surface 12 b. That is, the pressing member 140 may be provided on the bottom surface of the punch 131. Here, since the pressing surface 141 is disposed below the cutting blade 131a of the punch 131, the pressing member 140 may press the uncoated part 12 to increase the tension of the uncoated part 12 before the punch 131 cuts the joining surface 12 a. Therefore, wrinkles of the uncoated portion 12 can be effectively removed.

Here, the pressing member 140 may press the uncoated surface 12b of the uncoated portion 12 to increase the tension of the uncoated portion 12, thereby preventing the connecting surface 12a of the uncoated portion 12 from being wrinkled.

As shown in fig. 12, in step (e), the connecting surface 12a of the uncoated portion 12 disposed between the pair of second strippers 122 is cut using the punch 131 of the upper mechanism 130.

That is, when the punch holder 132 is lowered again, the punch 131 provided at the uppermost end portion cuts the uncoated portion 12. Here, since the connecting surface 12a of the uncoated portion 12 is disposed above the uncoated surface 12b, the punch 131 first cuts the connecting surface 12 a. Here, since wrinkles are not generated on the joining surface 12a, the joining surface 12a can be cut without forming burrs, thereby improving cutting quality.

As shown in fig. 13, in step (f), when the cutting of the connecting surface 12a is completed, the second ejector 122 presses the uncoated surface 12b of the uncoated portion 12a second time so as to fix the uncoated surface 12b to the die 111 of the lower mechanism 110.

That is, when the punch holder 132 is lowered again, the second ejector 122 secondarily presses the uncoated surface 12b while being lowered, so as to fix the uncoated surface 12b to the die 111 of the lower mechanism 110.

In step (g), when the uncoated surface 12b is completely fixed, the uncoated surface 12b may be cut by the punch 131 of the upper mechanism 130 to complete the electrode tab.

That is, when the punch holder 132 is lowered again, the punch 131 of the upper mechanism that cuts the connecting surface 12a may continue to cut the uncoated surface 12 b. Here, since both ends of the uncoated surface 12b are fixed by the second ejector 122, the uncoated surface 12b can be cut without forming burrs.

Therefore, in the punching method for a secondary battery according to the first embodiment of the present invention, the coated portion 11 and the uncoated portion 12 of the electrode 10 are respectively pressed and fixed. Here, the uncoated surface 12b of the uncoated portion 12 may be primarily pressed without being fixed, and then the uncoated surface 12b may be secondarily pressed to be fixed. Therefore, the uncoated portion of the electrode 10 can be accurately cut to improve the cutting quality. In particular, when cutting the uncoated portion 12, the uncoated portion may be pressed by the pressing member 140 to increase the tension to improve the cutting accuracy of the uncoated portion.

Hereinafter, in the description of another embodiment of the present invention, constituent parts of the second embodiment having the same functions as those of the first embodiment are given the same reference numerals in the drawings, and thus, the repetitive description will be omitted.

[ punching device for secondary battery according to second embodiment of the invention ]

As shown in fig. 14, a punching device 100 for a secondary battery according to a second embodiment of the present invention includes a lower mechanism 110, a ejector 120, an upper mechanism 130, and a pressing member 140. The ejector 120 includes first and second ejectors 121 and 122.

Here, the first ejector 121 is mounted on the punch holder 132 so that the length can be adjusted in the direction of the lower mechanism 110 or in the opposite direction. That is, the height of the first ejector 121 may be adjusted according to the electrode 10 provided on the lower mechanism 110. Therefore, when the punch holder 132 of the upper mechanism 130 is lowered, the time required to allow the first ejector 121 to press the electrode 10 can be adjusted, and moreover, the pressing force applied to the electrode 10 can be adjusted.

For example, the first ejector 121 includes a first guide member 121a disposed on a top surface of the first ejector 121 to pass through the punch holder 132, a first fixing nut 121b coupled with a front end of the first guide member 121a passing through the punch holder 132, and a first elastic member 121c wound on the first guide member 121a between the first ejector 121 and the punch holder 132.

That is, the first ejector 121 is mounted on the punch holder 132 so as to be movable in the direction of the lower mechanism 110 or in the opposite direction by the first guide member 121a, and is prevented from being separated from the punch holder 132 by the first fixing nut 121 b. Here, since the first fixing nut 121b is moved in the longitudinal direction of the first guide member 121a, the height of the first ejector 121 can be adjusted. Also, the first ejector 121 may be disposed to be spaced apart from the punch holder 132 by the elastic force of the first elastic member 121 c.

The second ejector 122 is mounted on the punch holder 132 so that the length can be adjusted in the direction of the lower mechanism 110 or in the opposite direction. That is, the height of the second ejector 122 may be adjusted according to the electrode 10 provided on the lower mechanism 110. Therefore, when the punch holder 132 of the upper mechanism 130 is lowered, the time required to allow the second ejector 122 to press the electrode 10 can be adjusted, and moreover, the pressing force applied to the electrode 10 can be adjusted.

For example, the second ejector 122 includes a second guide member 122a provided on a top surface of the second ejector 122 to pass through the punch holder 132, a second fixing nut 122b coupled with a front end of the second guide member 122a passing through the punch holder 132, and a second elastic member 122c wound around the second guide member 122a between the second ejector 122 and the punch holder 132.

That is, the second ejector 122 is mounted on the punch holder 132 so as to be movable in the direction of the lower mechanism 110 or in the opposite direction by the second guide member 122a, and is prevented from being separated from the punch holder 132 by the second fixing nut 122 b. Here, since the second fixing nut 122b moves in the longitudinal direction of the second guide member 122a, the height of the second ejector 122 may be adjusted. Also, the second ejector 122 may be disposed to be spaced apart from the punch holder 132 by the elastic force of the second elastic member 122 c.

The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description and the exemplary embodiments described herein. Various modifications made within the meaning of an equivalent of the claims of the invention and within the claims are to be considered as falling within the scope of the invention.