Method and apparatus for manufacturing secondary batteries

Abstract

The present invention relates to a method for manufacturing a secondary battery, and more specifically, to an apparatus and method for manufacturing a secondary battery that can effectively cut pouches and remove foreign matter through a roll conveying process, and can continuously form unit pouches. According to one embodiment of the present invention, a method for manufacturing a secondary battery and an apparatus using the same can be provided, comprising: a conveying step of supplying pouch fabric via a roll conveying device; and a slitting step of partially cutting the conveyed pouch fabric in a direction perpendicular to the conveying direction to correspond to the length of a unit pouch, but excluding both ends in the cutting direction of the pouch fabric, wherein the conveying step includes a double-ended support conveying step after the slitting step of supporting and conveying the uncut portions at both ends of the pouch fabric, excluding the cut portions.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a secondary battery, and more specifically, to a manufacturing apparatus and method for a secondary battery capable of effectively performing pouch cutting and foreign matter removal through a roll conveyance process and continuously forming unit pouches.

Background Art

[0002] A secondary battery is a battery that can be repeatedly used through a discharging process of converting chemical energy into electrical energy and a charging process of converting electrical energy into chemical energy.

[0003] Secondary batteries may include nickel-cadmium (Ni-Cd) batteries, nickel-metal hydride (Ni-MH) batteries, lithium-metal batteries, lithium-ion (Li-Ion) batteries, and lithium-ion polymer batteries (hereinafter referred to as "LIPB").

[0004] Lithium secondary batteries have a cycle life of about 500 times or more and a short charging time of about 1 to 2 hours. They are about 30% to 40% lighter than nickel-metal hydride batteries and can be lightweight. Among existing secondary batteries, they have the highest voltage per unit cell (30 to 37V) and excellent energy density, and may have characteristics optimized for mobile devices.

[0005] Lithium secondary batteries can be provided as pouch-type secondary batteries, where the battery cells are sealed by a pouch made of an aluminum sealing material.

[0006] Pouch-type secondary batteries may include an electrode assembly housed in a pouch as a sealing material, a lead electrically connected to an electrode tab of the electrode provided in the electrode assembly and drawn out to the outside of the pouch, and an insulating film for electrically insulating the lead.

[0007] A pouch is typically formed from a core material in the form of a thin aluminum sheet and an insulating film coated on the top and bottom surfaces of the core material. The insulating film is typically made of polypropylene (PP) film.

[0008] The manufacture of single-pouch rechargeable batteries requires unit pouches. These unit pouches are formed by a slitting process, which involves cutting a roll of pouch material at regular intervals.

[0009] In one example, the width of the pouch fabric may be equal to the width of a single pouch, and the pouch fabric may be cut at intervals corresponding to the length of a single pouch to form unit pouches.

[0010] While pouch slitting is performed by a slit cutter, a problem can arise during the slitting process where aluminum fragments, or foreign matter, are generated and adhere to the top and bottom surfaces of the pouch. These foreign objects can cause damage to the pouch as it is transported through the rolls, and subsequently lead to defects in the molding process that deforms the pouch's shape. Of course, if such foreign matter is not properly removed, it can result in a decrease in the performance of the manufactured pouch-type rechargeable battery.

[0011] Korean Published Patent 10-2021-0047469 (hereinafter referred to as the "Prior Patent") discloses an example in which the pouch slitting process and molding process are carried out sequentially.

[0012] The features disclosed in the prior patent can be explained using Figure 1 as follows:

[0013] The pouch dough P is continuously supplied via a roll conveying device R and can be cut into unit pouches by a slit cutter 1. At this time, a foreign matter removal device 2 is provided to remove foreign matter generated by the cutting. The foreign matter removal device 2 is configured to suck air, and removes foreign matter from the pouch by suction.

[0014] The cut unit pouches are preheated by a preheating lamp 3 and then molded by a molding device 4. The molding device 4 is a device for forming a housing section, or housing space, in which the electrode assembly is housed through forming. The unit pouch 5, after the molding of the pouch is complete, is then assembled with the electrode assembly through an assembly process.

[0015] As shown in the diagram, the pouch material P is transported by a roll conveying device R until it reaches the slit cutter 1, and then moves on the stage 6 via another conveying device. In other words, the cut unit pouches are moved on the stage 6 by pickers and linear conveying devices (not shown), so foreign matter can only be removed from the top surface of the unit pouch. In other words, there is a problem in that it is difficult to remove foreign matter that may adhere to the bottom surface of the unit pouch during the slitting process.

[0016] Furthermore, the pouch dough P is conveyed via a roll conveying device only up to the slitting process, and thereafter the molding process is carried out while the unit pouch is conveyed via a separate conveying device. Therefore, there is a problem in that it is difficult to provide a pouch molding method in which the conveying process of the pouch dough, the slitting process, and the molding process are carried out continuously and organically.

[0017] In particular, the molding process that forms the containment section of the pouch requires complex loading and unloading equipment for loading, molding, and unloading the unit pouches, which inevitably increases the process time. [Overview of the project] [Problems that the invention aims to solve]

[0018] The present invention aims to solve the problems of conventional methods and apparatus for manufacturing secondary batteries. In particular, it aims to solve the problems of pouch molding methods and apparatus for forming unit pouches from pouch material.

[0019] One embodiment of the present invention provides a method and apparatus for manufacturing a secondary battery that can perform a forming process using a roll conveying device.

[0020] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery is provided that can effectively remove foreign matter generated during pouch slitting by using a horizontal blower and a vertical blower in combination.

[0021] One embodiment of the present invention provides a method and apparatus for manufacturing a secondary battery that can use a roll conveying device to use both a horizontal blower and a vertical blower.

[0022] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery is provided, which involves performing vertical blowing on a pouch that is suspended in the air at both ends by a roll conveying device, thereby effectively removing foreign matter from the cut surface of the pouch.

[0023] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery is provided, which allows a roll conveying device to sequentially and continuously perform a slitting process, a blowing process, and a forming process. [Means for solving the problem]

[0024] To achieve the aforementioned objectives, according to one embodiment of the present invention, a method for manufacturing a secondary battery is provided, comprising: a conveying step of supplying pouch fabric via a roll conveying device; and a slitting step of cutting the conveyed pouch fabric in a direction perpendicular to the conveying direction to correspond to the length of a unit pouch, but partially cutting the pouch fabric such that both ends are excluded in the cutting direction of the pouch fabric, wherein the conveying step includes a double-ended support conveying step of supporting and conveying the uncut portions at both ends of the pouch fabric after the slitting step, excluding the cut portions.

[0025] The conveying process preferably includes an overall support conveying process in which the entire widthwise direction of the pouch fabric is supported and conveyed before the slitting process.

[0026] Through the overall support conveyance process, the pouch fabric can be stably supported and supplied before the slitting process. Through the both-end support conveyance process, except for the cutting part of the pouch, the non-cut parts at both ends are supported, enabling continuous conveyance of the pouch fabric and avoidance of the cutting part.

[0027] Preferably, it includes a blowing process for removing foreign matters generated in the slitting process through a blower.

[0028] The blowing process may include a horizontal blowing process of supplying gas horizontally to the upper and lower surfaces of the pouch fabric conveyed through the roll conveyance device.

[0029] The blowing process may include a vertical blowing process of supplying gas vertically to the upper and lower surfaces of the pouch fabric conveyed through the roll conveyance device.

[0030] After the horizontal blowing process, the vertical blowing process may be performed, or vice versa.

[0031] Effective blowing can be achieved by performing blowing while maintaining the continuity of the pouch fabric through partial cutting of the pouch fabric.

[0032] It may include a forming process of pressing the pouch fabric to form a housing part for the electrode assembly.

[0033] The input and discharge of the pouch fabric in the forming process can also be performed through the roll supply device. Therefore, a separate input and discharge device is not required.

[0034] The forming process is preferably performed after the slitting process and the blowing process.

[0035] The slitting process, the blowing process, and the forming process can be continuously performed without interruption of the pouch fabric through the roll conveyance device.

[0036] The roll conveying device repeatedly stops after conveying the length of the unit pouch, and the slitting and forming processes can be performed during these stops. That is, they can be performed simultaneously at different locations via different devices.

[0037] The process may include a cutting step in which the uncut portion of the pouch fabric is cut to form the unit pouch. The cutting step may also be performed simultaneously at a different location from the slitting step and the forming step.

[0038] To achieve the aforementioned objectives, according to one embodiment of the present invention, a secondary battery manufacturing apparatus can be provided, comprising: a roll conveying device for supplying and conveying pouch fabric; a slit cutter provided to partially cut the conveyed pouch fabric in a direction perpendicular to the conveying direction so as to correspond to the length of a unit pouch, and to maintain the conveyance of the pouch fabric via the roll conveying device even after cutting, wherein the roll conveying device comprises a whole support roll located upstream of the slit cutter and supporting the entire widthwise portion of the pouch fabric, and a partial support roll located downstream of the slit cutter and supporting the uncut portions at both ends of the pouch fabric except for the cut portion.

[0039] The width of the pouch fabric may be the same as the width of the unit pouch.

[0040] Preferably, the system includes a blower located downstream of the slit cutter to remove foreign matter generated during the slitting process.

[0041] Preferably, the blower includes a horizontal blower that supplies gas horizontally to the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device to remove foreign matter generated in the slitting process.

[0042] Preferably, the blower includes a vertical blower that supplies gas vertically to the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device to remove foreign matter generated in the slitting process.

[0043] Preferably, the vertical blower includes an upper vertical blower and a lower vertical blower that are spaced apart from each other along the conveying direction via the roll conveying device.

[0044] The horizontal blower may be located upstream of the vertical blower, or vice versa.

[0045] Preferably, the system includes a forming device located downstream of the blower, which pressurizes the pouch fabric, which is conveyed via the roll conveying device, to form the housing portion of the electrode assembly.

[0046] The partial support roll is preferably located downstream of the forming device.

[0047] To achieve the aforementioned objectives, according to one embodiment of the present invention, a pouch molding apparatus for secondary batteries can be provided, comprising: a roll conveying device for supplying and conveying pouch fabric; a slit cutter provided to partially cut the conveyed pouch fabric in a direction perpendicular to the conveying direction to correspond to the length of a unit pouch, with both ends excluded from cutting in the cutting direction, and to maintain the conveyance of the pouch fabric via the roll conveying device even after cutting; a horizontal blower for removing foreign matter generated during pouch cutting in a horizontal direction from the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device; and a vertical blower for removing foreign matter generated during pouch cutting in a vertical direction from the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device.

[0048] The pouch dough is provided in roll form, and the pouch dough can be continuously supplied via a roll conveying device as the roll is unrolled. In other words, the pouch dough is continuously conveyed via the roll conveying device without interruption.

[0049] When the slit cutter completely cuts the pouch fabric in the width direction, the continuous state of the pouch fabric is no longer maintained, and a unit pouch is formed. In this embodiment, the slit cutter can cut only the central portion in the width direction of the pouch fabric to form a cut portion. Therefore, uncut portions are formed at both ends in the width direction of the pouch fabric. This allows the continuous state of the pouch fabric to be maintained even after passing through the slit cutter. This means that the pouch fabric can be continuously conveyed via a roll feeder after the slit cutter.

[0050] The unit pouch may refer to a pouch, i.e., a sealing material, for forming a single secondary battery cell. The pouch material can be partially cut at regular intervals to form the unit pouch using a slit cutter. The uncut portions can then be completely cut off in a later process using another cutter to finally form the unit pouch.

[0051] The width of the pouch fabric may be the same as the width or length of the unit pouch. In this case, the interval between partial cuts of the pouch fabric may be the same as the length or width of the unit pouch.

[0052] The horizontal blower may include a blower nozzle that injects gas on one side and a suction nozzle that sucks gas in corresponding to the blower nozzle on the other side. In other words, it can simultaneously scatter foreign matter and suck up the scattered foreign matter.

[0053] Preferably, a plurality of the blower nozzles and suction nozzles are provided along the conveying direction via the roll conveying device.

[0054] Preferably, the blower nozzle and the suction nozzle are provided on the upper and lower surfaces, respectively, of the unit pouch.

[0055] The positions of the blower nozzle and suction nozzle may be arranged so as to intersect along the conveying direction via the roll conveying device. That is, the positions of a pair of blower nozzles and suction nozzles and an adjacent pair of blower nozzles and suction nozzles may be diametrically opposed. That is, the gas injection directions of adjacent blower nozzles may be diametrically opposed.

[0056] The vertical blower may include an upper vertical blower and a lower vertical blower, which are spaced apart from each other along the conveying direction via the roll conveying device.

[0057] Preferably, the gas injection centers of the upper vertical blower and the lower vertical blower are positioned to intersect each other.

[0058] The horizontal blower may be positioned in front of the vertical blower. That is, horizontal blowing may occur after vertical blowing along the conveying direction of the pouch fabric. Of course, the opposite is also possible.

[0059] On the other hand, foreign matter generated during the slitting process is most likely to adhere to or near the cutting line. Therefore, horizontal and vertical blowers can be positioned to coincide with the cutting line.

[0060] The blowing via the horizontal and vertical blowers may be performed simultaneously with the transport of the pouch fabric, or when the transport of the pouch fabric has stopped. Of course, blowing may be performed in all conditions, both when the pouch fabric is being transported and when it is stopped. The slitting may be performed when the pouch fabric is stopped.

[0061] The pouch fabric can move one pitch in a sequence corresponding to the width or length of the unit pouch, then stop repeatedly, and slitting can be performed when it stops. Then, it can move one pitch, stop, and slitting can be performed again. Therefore, the blower can be positioned at a location corresponding to n pitches downstream from the slit cutter, where n is a natural number.

[0062] This allows the blower to be positioned opposite the cutting line of the pouch, enabling effective blowing of the pouch fabric while it is stationary.

[0063] The roll conveying device may include an unwinding roll that rotatably supports the pouch dough in a rolled state, a first support roll that supports the pouch dough upstream of the slit cutter, and a second support roll that supports the pouch dough downstream of the horizontal blower and the vertical blower.

[0064] Slitting and blowing processes can be performed on the pouch fabric between the first support roll and the second support roll.

[0065] The first and second support rolls may be configured to support the entire width of the pouch fabric. This enables stable support and transport of the pouch fabric. In particular, it is preferable that the first and second support rolls are configured to support the top and bottom surfaces of the pouch fabric simultaneously.

[0066] A forming device may be provided for forming the housing portion of the electrode assembly with the pouch fabric conveyed via the roll conveying device. That is, the slitting process, blowing process, and forming process may be carried out using conveyance via a roll conveying device in a continuous manner.

[0067] The forming apparatus may include a lower die and an upper press for heat-pressurizing the unit pouch placed on the lower die.

[0068] The forming device may include a third support roll downstream for supporting and transporting the unit pouches.

[0069] The third support roll may be provided to support the uncut portions at both ends in the width direction of the unit pouch, which have been excluded from cutting by the slit cutter. That is, the third support roll may be provided to support the pouch fabric while avoiding the portion that houses the electrode assembly formed after the pouch forming process. That is, the third support roll may be provided to support only both ends in the width direction of the pouch fabric. Of course, the third support roll may be provided to support both the upper and lower surfaces of the pouch fabric simultaneously.

[0070] A linear moving device may be provided for linearly moving the pouch dough discharged by the third support roll.

[0071] A linear transfer device may be configured to provide unit pouches that have been discharged or supplied by a third support roll and formed. On the linear transfer device, unit pouches are not completely separated from nearby unit pouches; that is, they are connected by non-cutting sections.

[0072] Therefore, the unit pouches can be completely separated from each other by cutting the non-cutting portion on the linear moving device.

[0073] After the unit pouches are separated, they are moved via a linear transfer device and can then be moved to the assembly process by another means, such as a picker.

[0074] The linear moving device may include a cutter for cutting the uncut portion of the unit pouch.

[0075] The cutters may be provided in four locations, corresponding to the four corners of the unit pouch. Of course, two cutters may be provided so that the unit pouch can be cut after it has been moved by one pitch.

[0076] Preferably, the roll conveying device is configured to stop after conveying the length or width of a unit pouch, and to repeat the conveying and stopping process.

[0077] To achieve the aforementioned objectives, according to one embodiment of the present invention, a method for manufacturing a pouch-type secondary battery is provided, comprising: a conveying step of supplying pouch fabric via a roll conveying device; a slitting step of cutting the conveyed pouch fabric in a direction perpendicular to the conveying direction to correspond to the length of a unit pouch; a blowing step of removing foreign matter generated in the slitting step via a blower; and a forming step of pressurizing the pouch fabric to form a housing portion for an electrode assembly, wherein the slitting step, blowing step and forming step are performed continuously via the roll conveying device, and in the slitting step, both ends of the pouch fabric are partially cut so as to be excluded from cutting in the cutting direction.

[0078] The roll conveying device is preferably configured to repeatedly stop after conveying a length equal to the length of a unit pouch. [Effects of the Invention]

[0079] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery can be provided that allows a forming process to be performed using a roll conveying device.

[0080] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery can be provided that effectively removes foreign matter generated during pouch slitting by using a horizontal blower and a vertical blower in combination.

[0081] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery can be provided that allows the use of both a horizontal blower and a vertical blower using a roll conveying device.

[0082] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery can be provided that performs vertical blowing on a pouch with both ends suspended in the air by a roll conveying device, thereby effectively removing foreign matter from the cut surface of the pouch.

[0083] In one embodiment of the present invention, a method and apparatus for manufacturing a secondary battery can be provided that allows a roll conveying device to sequentially and continuously perform a slitting process, a blowing process, and a forming process. [Brief explanation of the drawing]

[0084] [Figure 1] This figure shows a conventional pouch molding apparatus and method.

[0085] [Figure 2] This is a side view of a pouch molding apparatus according to one embodiment of the present invention.

[0086] [Figure 3] This figure shows a top view of the molding apparatus shown in Figure 2.

[0087] [Figure 4] This figure shows another embodiment regarding the positioning of the vertical and horizontal blowers.

[0088] [Figure 5] This figure schematically shows a pouch molding apparatus and molding method according to one embodiment of the present invention.

[0089] [Figure 6] This diagram shows a top-down view of the pouch dough after it has been transported following the forming process. [Modes for carrying out the invention]

[0090] A pouch molding apparatus and molding method for secondary batteries according to one embodiment of the present invention will be described in detail below with reference to the attached drawings.

[0091] Figure 2 shows a pouch molding apparatus according to one embodiment of the present invention, viewed from the side, of the pouch dough being conveyed via a roll conveying device, and Figure 3 shows a pouch molding apparatus according to one embodiment of the present invention, viewed from above, of the pouch dough being conveyed via a roll conveying device.

[0092] The roll conveying device may include a first support roll R2, and the roll conveying device means a device that can continuously convey pouch dough P between rolls. Conveying can be performed continuously without stopping, or stopping can be repeated after conveying at regular intervals. Further details about the roll conveying device will be described later.

[0093] As shown in Figures 2 and 3, the pouch fabric P can be conveyed while being supported by a first support roll R2, and can be cut by a slit cutter 10 after passing through the first support roll R2. It can be said that the slit cutter 10 is located downstream of the first support roll R2 along the conveying direction, and conversely, the first support roll R2 is located upstream of the slit cutter 10.

[0094] Here, it is preferable that the slit cutter 10 does not cut the entire width of the pouch fabric P. That is, it is preferable to cut the central part of the width but not both ends of the width. More specifically, as shown in Figure 3, the slit cutter 10 cuts the central part of the pouch fabric P to form a cut portion through the cutting line S, and uncut portions N may be formed at both ends of the cutting line S.

[0095] The non-cut portion N maintains the continuity of the pouch fabric P, and therefore, continuous conveyance by the roll conveying device is possible even after slitting.

[0096] The slit cutter 10 is configured to cut the pouch fabric P to form unit pouches. That is, the pouch fabric P is cut at regular intervals or to a regular length, and a unit pouch can be formed when both ends are completely cut. In other words, the total width of the pouch fabric P may correspond to the length of the unit pouch, and in this case, the cutting interval of the pouch fabric P, that is, the distance between nearby cutting lines S and cutting lines S, may correspond to the width of the unit pouch.

[0097] As shown in the figure, the pouch dough P is supported by a roll conveying device, and therefore the slit cutter 10 cuts the pouch dough P while it is suspended in the air. Any foreign matter d generated at this time can be placed near the cutting line S. In particular, foreign matter can adhere to the upper and lower surfaces of the pouch dough P.

[0098] A horizontal blower 20 may be provided to effectively remove these foreign objects from the pouch dough P. The horizontal blower 20 may be located in front of the slit cutter 10. That is, after slitting, the foreign objects d can be removed via the horizontal blower 20.

[0099] The horizontal blower 20 may be provided to remove foreign matter horizontally from the top and bottom surfaces of the pouch dough P or unit pouches that are conveyed via the roll conveying device.

[0100] The horizontal blower 20 may include blower nozzles 21 and 23 that inject gas on one side, and suction nozzles 22 and 24 that suck in gas on the other side in correspondence with the blower nozzles 21 and 23.

[0101] Blower nozzles 21 and 23 may be configured to inject gas in the widthwise and horizontal directions of the pouch fabric P. The gas injected may be compressed air.

[0102] The blower nozzles 21 and 23 may be configured to move in the width direction. That is, they can move in the direction of the other side while spraying air from one side of the pouch fabric P in the width direction. In other words, they can perform the function of gradually pushing out foreign matter.

[0103] Suction nozzles 22 and 24 may be provided on the opposite side of the blower nozzles 21 and 23, and one blower nozzle and one suction nozzle may correspond one-to-one while facing each other. The suction nozzles may be provided so as to be fixed without moving in the width direction of the pouch fabric P.

[0104] Here, in order to more effectively remove foreign matter in the horizontal direction, multiple pairs of blower nozzles and suction nozzles may be provided along the conveying direction. Furthermore, it is preferable that the directions in which air is injected and suctioned intersect with each other.

[0105] Furthermore, it is preferable that the blower nozzle and suction nozzle pair be arranged so as to be vertically symmetrical with respect to the pouch fabric P. It is also preferable that the directions in which air is injected and sucked are equal.

[0106] For example, a blower nozzle and a suction nozzle positioned above and below the slit cutter 10 may be configured to spray or suck air in the same direction. Similarly, a blower nozzle and a suction nozzle positioned above and below the slit cutter 10 may also be configured to spray or suck air in the same direction. However, as shown in Figure 3, it is preferable that the directions of air spraying and suctioning are opposite. This allows for more effective removal of foreign matter.

[0107] On the other hand, even after removing foreign matter horizontally, there is still a possibility that some foreign matter may remain. In particular, there is a possibility that foreign matter may remain in the thickness portion of the cutting line S.

[0108] To remove these foreign objects more effectively, vertical blowers 30 and 40 may be provided. The vertical blowers 30 and 40 may be provided to remove foreign objects vertically from the top and bottom surfaces of the pouch dough P or unit pouches that are conveyed via a roll conveying device.

[0109] The vertical blowers 30 and 40 may include an upper vertical blower 30 and a lower vertical blower 40. The upper vertical blower 30 can inject gas downward toward the upper surface of the pouch fabric P, and the lower vertical blower 40 can inject gas upward toward the lower surface of the pouch fabric P.

[0110] Here, it is preferable that the injection centers of the upper vertical blower 30 and the lower vertical blower 40 are not equal to each other. That is, it is preferable that they have a predetermined deviation. This makes it possible to generate vertical oscillation of the pouch fabric P more effectively. In particular, with respect to the cutting line S, the upper blower can inject gas toward one side adjacent to the cutting line S, and the lower blower can inject gas toward the other side adjacent to the cutting line S. At this time, with respect to the cutting line S, the pouch fabric P on one side can move upward, and the pouch fabric P on the other side can move downward. That is, the pouch fabric P can expand vertically with respect to the cutting line S, and at this time, the cut surface by the cutting line S (i.e., the thickness surface of the cut pouch fabric) is exposed and affected by the injected gas. And, since uncut portions N are formed at both ends of the cutting line S, there is a certain limit to the width to which the pouch fabric expands.

[0111] Furthermore, the vertical blowers 30 and 40 cause the pouch dough P to flutter up and down, allowing it to flow. At this time, foreign matter d adhering to the pouch dough can be effectively removed while being detached from the dough P.

[0112] On the other hand, the vertical blowers 30 and 40 may be configured to move along the cutting line S. That is, they can inject gas while moving.

[0113] As shown in Figure 3, the horizontal blower 20 and the vertical blowers 30 and 40 may be configured to remove foreign matter in line with the cutting line S. That is, the cutting line S does not move continuously, but can stop at positions corresponding to the horizontal blower 20 and the vertical blowers 30 and 40.

[0114] In other words, the pouch dough P can move and stop repeatedly via the roll conveying device without moving continuously. Between movement and stopping, the pouch dough P can move by the width of a unit pouch. That is, when the pouch dough moves by a certain pitch and stops, a cutting line S is formed by the slit cutter 10, and after cutting is complete, the pouch dough P can move by another certain pitch and stop to be cut again.

[0115] Here, it is preferable that when the pouch dough P is stopped, not only slitting but also removal of foreign matter via the horizontal blower and vertical blower is performed. Therefore, it is preferable that the slit cutter 10, the horizontal blower and the vertical blower be positioned at intervals of n pitches along the longitudinal direction of the pouch dough P, where n is a natural number.

[0116] Ultimately, when the pouch fabric P is stopped, it is preferable that the slit cutter drive, horizontal blower drive, and vertical blower drive are performed simultaneously at different positions.

[0117] Figure 4 shows an example where the positions of the horizontal blower 20 and the vertical blowers 30 and 40 shown in Figure 3 are swapped. The vertical blowers may have a structure that makes it difficult to include a suction nozzle for sucking up foreign matter. Therefore, foreign matter d scattered via the vertical blowers 30 and 40 can reattach to the pouch fabric P. Of course, foreign matter on the cut surface can be effectively removed via the vertical blowers.

[0118] Therefore, as shown in Figure 4, it may be very effective to remove foreign matter primarily via vertical blowers 30 and 40 and secondarily via horizontal blower 20. In other words, it is preferable that the horizontal blower 20 be located downstream of the vertical blowers 30 and 40.

[0119] The following describes in more detail the roll conveying devices R1 to R4 and the manufacturing method of a secondary battery manufacturing apparatus according to one embodiment of the present invention.

[0120] As shown in the figure, the roll conveying device may include an unwinding roll R1 that rotatably supports the pouch dough in a rolled state. That is, the pouch dough can be supplied by the unwinding roll R1. The pouch dough can be supplied continuously from the unwinding roll R1 without being cut. That is, the pouch dough conveying process can be carried out by driving the roll conveying device. As mentioned above, it is preferable that the conveying of the pouch dough via the roll conveying device is carried out in such a way that conveying at a constant pitch is followed by repeated stops.

[0121] The roll conveying device may include a first support roll R2 that supports the pouch fabric P upstream of the slit cutter 10. The first support roll R2 can stably and continuously convey the pouch fabric P conveyed from the unwinding roll R1 to the slit cutter 10.

[0122] After a slitting process in which the pouch fabric P is partially cut at a constant pitch by the slit cutter 10, a blowing process may be performed to remove foreign matter.

[0123] For the blowing process, horizontal blowers 20 and vertical blowers 30 and 40 are provided, and it is preferable that these blowers be installed at pre-set positions on the conveying path of the pouch dough P.

[0124] It is preferable that a second support roll R3 be provided downstream of the horizontal blower 20 and the vertical blowers 30 and 40. That is, if the roll conveying device includes a first support roll R2 and a second support roll R3, the slitting and blowing processes of the pouch dough P can be performed between the first support roll and the second support roll. In other words, the first support roll and the second support roll not only have the function of conveying the pouch dough P, but also the function of supporting the pouch dough during the slitting and blowing processes.

[0125] According to this embodiment, the slitting process, the blowing process, and the forming process can be performed continuously using a roll conveying device.

[0126] The forming process may be a process for pressurizing the unit pouch to form a housing or groove in which the electrode assembly will be contained. In the forming process, the unit pouch can be said to be in a state where it is not completely separated from the pouch material.

[0127] To perform the forming process, the forming device 40 may be located on the transport path of the pouch dough P. More preferably, the forming process may be performed after the blowing process.

[0128] The pouch dough P, which has undergone the slitting and blowing processes, can be conveyed by the second support roll R3 and supplied to the forming device 40. In other words, no separate device is needed to supply and discharge the pouches to the forming device; the roll conveying device can be used as is.

[0129] The forming apparatus may include an upper press 41 that applies pressure to the pouch dough P from top to bottom, and a lower die 42 that supports the pouch dough P from below when the upper press 41 applies pressure. Specifically, the upper press 41 may be located above the upper surface of the pouch dough P, and the lower die 42 may be located below the lower surface of the pouch dough P, separated from the bottom surface. During the forming process, the upper press 41 and the lower die 42 move toward the pouch dough, and the pouch dough interposed between the upper press 41 and the lower die 42 can be formed at this time. The shapes of the upper press 41 and the lower die 42 may be formed to correspond to the profile of the unit pouch after forming is complete.

[0130] During the forming process, the stopped pouch dough can be formed using such a forming device, and the pouch dough can be transported without interference from the forming device upon completion of the forming process.

[0131] The forming device 40 may include strippers (not shown) for securing both ends or the frame of the unit pouch during forming. These strippers may be part of the lower die 42.

[0132] The roll conveying device may include a third support roll R4. The third support roll R4 may be located downstream of the forming device 40. The pouch dough may be supported and conveyed and formed between the second support roll R3 and the third support roll R4.

[0133] Figure 6 shows the pouch fabric P after the slitting and forming processes have been completed.

[0134] As shown in the figure, the pouch between the cutting lines S may be a unit pouch and must ultimately be completely separated from nearby unit pouches. That is, the uncut portion N must ultimately be cut. For this reason, it is preferable that a cutting or separation step is performed after the forming step in which the uncut portion N is cut.

[0135] As shown in Figures 5 and 6, when the forming process creates a storage section a in the pouch, a step is formed on the pouch surface. Therefore, it is not easy to support or convey this step with a roll. On the other hand, the storage section a is located between the cutting lines S, and a non-forming section, i.e., a flat section, is formed between the storage section a and the cutting lines S for the subsequent pouch sealing.

[0136] Similarly, the containment section a is formed only at the center of the pouch dough P in the width direction, while non-forming sections, i.e., flat sections, are formed at both ends. As mentioned above, non-cut sections N are formed at both ends of the pouch dough P in the width direction. In other words, the cutting line S is formed only at the center of the pouch dough in the width direction. Therefore, the pouch dough P can maintain continuity through the non-cut sections N. That is, the pouch dough P can be conveyed using a roll conveying device even after the forming process.

[0137] For this reason, the third support roll R4 may have a different shape from the other support rolls R2 and R3. The first and second support rolls may be provided to support the entire width of the pouch above and below the pouch fabric. Therefore, the first and second support rolls can be called full support rolls. However, the third support roll may be provided to support only both ends of the pouch width. That is, it may be provided to support and transport the pouch fabric while avoiding the containment section a. Of course, the third support roll may be provided to support the top and bottom of the pouch. Therefore, the third support roll can be called a double-ended support roll or a partial support roll.

[0138] Here, the process of conveying the pouch dough via a roll conveying device is called the conveying process, and the conveying process can be subdivided according to the shape and position of the support rolls. For example, conveying using the entire support roll, such as the first or second support roll, is called the overall support conveying process, and conveying using partial support rolls, such as the third support roll, can be called the partial support conveying process.

[0139] On the other hand, two storage sections a may be formed in the width direction of the pouch fabric P. The portion indicated by the center line between the two storage sections a can be said to be the portion that will be folded when the electrode assembly and unit pouch are later assembled.

[0140] After the pouch forming process for creating the containment section a is completed, the pouch material P can be transported to the next process while being supported by the third support roll R4.

[0141] After the forming process is completed, the aforementioned cutting or separation process of the uncut portion N may be performed.

[0142] The pouch dough P, conveyed by the third support roll R4, can ultimately be formed into unit pouches by cutters 11 and 12. That is, the cutters 11 and 12 may be provided to cut the uncut portions N at each of the four corners of the unit pouch. Of course, it is also possible to form a unit pouch by cutting only two corners.

[0143] The pouch dough P conveyed by the third support roll R4 is supplied to the linear conveying device 60, where the unit pouches can be completely separated individually by a cutter.

[0144] The linear conveying device 60 may be provided with a pallet or jig for supporting and conveying each unit pouch.

[0145] The unit pouches, completely separated by the cutters 11 and 12, can be transported to the linear transport device 60 and then to the subsequent assembly process, namely the process in which the electrode assembly and the unit pouches are assembled.

[0146] A picker 50 may be provided near the linear conveying device 60 for picking up individually separated unit pouches and moving them to the assembly process location.

[0147] As mentioned above, the slitting process, blowing process, forming process, and separation process can be carried out via the roll conveying devices R1 to R4 while the pouch dough P is still intact. In particular, since both horizontal and vertical blowing can be performed in the blowing process, foreign matter generated during slitting can be removed very effectively.

[0148] Furthermore, the features of this roll conveying device and partial cutting slits allow slitting, blowing, forming, and separation to be performed simultaneously, enabling highly efficient and continuous pouch molding. In particular, since the roll conveying device can be used throughout the pouch molding process, it becomes possible to realize an efficient and easy-to-install molding apparatus. [Industrial applicability]

[0149] This is included in the detailed description of the present invention.

Claims

1. A conveying process that supplies pouch dough via a roll conveying device, The process includes a slitting step in which the conveyed pouch fabric is cut in a direction perpendicular to the conveying direction to correspond to the length of a unit pouch, but with the ends excluded from the cutting direction of the pouch fabric, A method for manufacturing a secondary battery, wherein the conveying step includes a double-ended conveying step in which, after the slitting step, the pouch fabric is conveyed while supporting the uncut portions at both ends, excluding the cut portions.

2. The method for manufacturing a secondary battery according to claim 1, wherein the conveying step includes a whole-support conveying step of supporting and conveying the entire widthwise portion of the pouch fabric before the slitting step.

3. A method for manufacturing a secondary battery according to claim 2, comprising a blowing step to remove foreign matter generated in the slitting step via a blower.

4. The method for manufacturing a secondary battery according to claim 3, wherein the blowing step includes a horizontal blowing step of supplying gas horizontally to the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device.

5. The method for manufacturing a secondary battery according to claim 4, wherein the blowing step includes a vertical blowing step of supplying gas vertically to the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device.

6. The method for manufacturing a secondary battery according to claim 5, wherein the vertical blowing step is performed after the horizontal blowing step.

7. A method for manufacturing a secondary battery according to claim 3, comprising a forming step of pressurizing the pouch fabric to form a housing for the electrode assembly.

8. The method for manufacturing a secondary battery according to claim 7, wherein the forming step is performed after the slitting step and the blowing step.

9. The method for manufacturing a secondary battery according to claim 8, wherein the slitting step, the blowing step, and the forming step are performed continuously without interruption of the pouch fabric via the roll conveying device.

10. The method for manufacturing a secondary battery according to claim 9, wherein the roll conveying device repeatedly stops after conveying the length of the unit pouch, and the slitting process and forming process are performed when the device stops.

11. A method for manufacturing a secondary battery according to claim 7, comprising a cutting step of cutting the uncut portion of the pouch fabric to form the unit pouch.

12. A roll conveying device that supplies and transports pouch dough, The system includes a slit cutter that cuts the conveyed pouch fabric in a direction perpendicular to the conveying direction to correspond to the length of a unit pouch, partially cutting so that both ends are excluded from cutting in the cutting direction, and maintaining the conveyance of the pouch fabric via the roll conveying device even after cutting, The roll conveying device includes a full support roll located upstream of the slit cutter and supporting the entire width of the pouch fabric, and a partial support roll located downstream of the slit cutter and supporting the uncut portions at both ends of the pouch fabric, excluding the cut portion, in a secondary battery manufacturing apparatus.

13. The apparatus for manufacturing a secondary battery according to claim 12, wherein the width of the pouch fabric is the same as the width of the unit pouch.

14. The secondary battery manufacturing apparatus according to claim 12, further comprising a blower located downstream of the slit cutter for removing foreign matter generated during the slitting process.

15. The secondary battery manufacturing apparatus according to claim 14, wherein the blower includes a horizontal blower that supplies gas horizontally to the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device to remove foreign matter generated in the slitting process.

16. The secondary battery manufacturing apparatus according to claim 15, wherein the blower includes a vertical blower that supplies gas vertically to the upper and lower surfaces of the pouch fabric conveyed via the roll conveying device to remove foreign matter generated in the slitting process.

17. The secondary battery manufacturing apparatus according to claim 16, wherein the vertical blower includes an upper vertical blower and a lower vertical blower that are spaced apart from each other along the conveying direction via the roll conveying device.

18. The secondary battery manufacturing apparatus according to claim 16, wherein the horizontal blower is located upstream of the vertical blower.

19. The secondary battery manufacturing apparatus according to claim 14, further comprising a forming device located downstream of the blower, which pressurizes the pouch fabric conveyed via the roll conveying device to form the housing portion of the electrode assembly.

20. The secondary battery manufacturing apparatus according to claim 19, wherein the partial support roll is located downstream of the forming device.

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