Folding device and method for a sealing portion of a pouch-type secondary battery

Abstract

The folding method according to the present invention is a method for folding a sealing part of a pouch-type secondary battery in which a sealing part protrudes in a lateral direction of a pouch incorporating an electrode assembly, and includes a sealing part heating step of heating the sealing part; and a folding step of pressing and folding the heated sealing part; wherein the heating step includes a non-contact heating step of using a heat lamp to irradiate light to the sealing part to heat it. The folding device according to the present invention is a folding device for a sealing part of a pouch-type secondary battery in which a sealing part protrudes in a lateral direction of a pouch incorporating an electrode assembly, and includes: a heating part for heating the sealing part; and a folding part for pressurizing and folding the heated sealing part; the heating part includes a heating lamp for irradiating light to the sealing part to heat it, and the heating lamps are respectively disposed above and below the sealing part, and heat the upper and lower surfaces of the sealing part simultaneously.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0015836, filed on February 7, 2022, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a folding device and a folding method for folding a sealing part formed along the periphery of a pouch-type secondary battery, and more particularly to a folding device and a folding method for folding a sealing part of a pouch-type secondary battery, which can solve the problem of a conventional structure in which excessive pressure is applied to the sealing part, causing damage to the sealing part. [Background technology]

[0003] Demand for secondary batteries as an energy source is rapidly increasing in various fields, including personal portable terminals and electric vehicles.

[0004] Unlike primary batteries, secondary batteries, which can be charged and discharged, are being developed not only for digital devices but also for transportation means such as electric vehicles.

[0005] Secondary batteries can be classified into various categories according to the materials of the positive and negative electrodes and their external shapes. Among them, lithium secondary batteries using lithium compounds have large capacity and a low self-discharge rate, and are therefore widely used in place of conventional nickel-cadmium secondary batteries.

[0006] The lithium secondary battery can be manufactured in various shapes, and typically, it is generally manufactured in a cylinder type, a prismatic type, or a pouch type.

[0007] Among these, the pouch-type secondary battery includes a pouch and an electrode assembly that is housed in the pouch and charges and discharges electrical energy.

[0008] The electrode assembly is constructed by alternately stacking negative and positive electrodes together with separators, and electrode tabs, each consisting of a negative electrode tab protruding from the negative electrode and a positive electrode tab protruding from the positive electrode, are joined to an electrode lead, one end of which protrudes outside the pouch. Depending on the manufacturing method of the positive and negative electrodes, the positive and negative electrode tabs may be positioned on opposite sides of each other or spaced apart on the same side.

[0009] Meanwhile, the pouch is manufactured with a structure that can be separated into two parts (for example, a structure that can be separated into an upper part and a lower part) so that it can accommodate the electrode assembly by covering one side and the other side thereof, and when the electrode assembly and electrolyte are placed inside, the two separated parts join together to form a sealing part 1.

[0010] For example, the pouch 2 may be manufactured so that the upper and lower portions each have a recessed groove of a predetermined size to accommodate the electrode assembly, and the periphery of the groove is flat along the periphery.

[0011] Therefore, when the upper and lower parts of the pouch 2 are closed after the electrode assembly is installed, the edges of the pouch 2 come into contact with each other, and in this state, the sealing part 1 is formed along the edge of the pouch 2, where the edges are heat-sealed to each other to seal the pouch 2.

[0012] Referring to Figure 1, which shows how a sealing part of a pouch-type secondary battery is folded in a conventional manner, the sealing part 1 of the pouch 2 is heated via heating blocks 3a and 3b. The heating blocks 3a and 3b are composed of an upper mold 3a and a lower mold 3b that can slide toward or away from each other, and the upper mold 3a and the lower mold 3b are provided in a heated state at a predetermined temperature.

[0013] When the sealing part 1 enters between the upper and lower dies 3a and 3b, the upper and lower dies 3a and 3b apply pressure and heat to the sealing part 1 from above and below to thermally seal the sealing part 1. Then, with the lower die 3b supporting the sealing part 1 from below, the upper die 3a slides sideways (left and right in FIG. 1) to fold the sealing part 1. Alternatively, the sealing part 1 may be folded by a separate folding device (not shown) after being removed from the heating block.

[0014] However, this heating method using pressure from the upper and lower dies 3a and 3b may cause damage such as dielectric breakdown to the synthetic resin layer made of thermoplastic resin contained in the pouch 2. Also, repeated use of the heating blocks 3a and 3b can cause temperature deviations, making it difficult to maintain sealing quality. Summary of the Invention [Problem to be solved by the invention]

[0015] Therefore, the main object of the present invention is to provide a folding device and folding method for a sealing part of a pouch-type secondary battery that can solve the problem of damage to the synthetic resin layer due to pressure generated by direct contact when heating the sealing part and can heat the sealing part while maintaining a uniform temperature. [Means for solving the problem]

[0016] To achieve the above-mentioned object, the present invention provides a method and device for folding a sealing part of a pouch-type secondary battery in which the sealing part protrudes laterally (left and right in Figure 2, etc.) along the periphery of a pouch containing an electrode assembly.

[0017] The folding method according to the present invention is a method for folding a sealing part of a pouch-type secondary battery, and includes a sealing part heating step of heating the sealing part; and a folding step of applying pressure to the heated sealing part and folding it; wherein the heating step includes a non-contact heating step of using a heat lamp to irradiate light onto the sealing part to heat it.

[0018] The sealing portion includes a layer made of a thermoplastic resin, and the thermoplastic resin is polypropylene.

[0019] The light emitted by the heat lamp is infrared light.

[0020] The heating step may further include a contact heating step of contacting a heated heating block with the sealing portion to heat it.

[0021] The heating step is configured such that a contact heating step is performed followed by a non-contact heating step, or a non-contact heating step is performed followed by a contact heating step.

[0022] In this case, one of the contact heating step and the non-contact heating step is performed first, and then a part of the folding step is performed, and the other of the contact heating step and the non-contact heating step is performed first, and then the remaining part of the folding step is performed.

[0023] The heating step is a non-contact heating step in which a heat lamp irradiates light onto the sealing portion to heat it, which is performed multiple times. After the non-contact heating step is performed first, a part of the folding step is performed, and in that state, the non-contact heating step is performed again, and then the remaining part of the folding step is performed.

[0024] and a taping step of attaching a fixing tape to fix the folded sealing portion after the folding step is completed.

[0025] The folding device according to the present invention is a folding device for a pouch-type secondary battery sealing part in which a sealing part protrudes toward a side of a pouch containing an electrode assembly, and includes a heating part for heating the sealing part and a folding part for applying pressure to the heated sealing part to fold it, and the heating part includes heat lamps for irradiating light onto the sealing part to heat it. In this case, the heat lamps are respectively disposed above and below the sealing part to heat the upper and lower surfaces of the sealing part simultaneously.

[0026] The heating unit includes an upper mold and a lower mold that can slide toward or away from each other, at least one of the upper mold and the lower mold is heated to a predetermined temperature, and further includes a heating block that contacts and heats the sealing unit when the sealing unit enters between the upper mold and the lower mold. In this case, the heating lamp and the heating block are configured to slide toward each other so that their positions can change.

[0027] The folding unit includes a fixing unit that fixes a folding point of the sealing unit when folding is performed, and a pressing unit that presses the sealing unit in a folding direction. [Effects of the Invention]

[0028] The present invention, which has the above-mentioned technical features, heats the sealing part by irradiating infrared rays from a heating lamp, thereby eliminating the conventional problem of damage caused by pressure acting on the sealing part (due to direct contact with the heating block).

[0029] Furthermore, since the heating temperature can be maintained uniformly compared to the conventional contact heating method, the sealing quality of the sealing part can be maintained constant.

[0030] At the same time, in the present invention, contact heating may be performed by contacting a heated heating block with the sealing portion, so that the sealing portion can be heated by applying an appropriate pressure. In this case, since contact heating is performed before or after non-contact heating, the pressure applied to the sealing portion can be lower than in conventional methods, thereby preventing damage to the sealing portion. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is a diagram showing a state in which a sealing part of a pouch-type secondary battery is folded in a conventional manner. [Figure 2] 10 is a view showing a state in which a sealing part of a pouch-type secondary battery is folded in a state where non-contact heating is performed in a heating step according to the present invention; FIG. [Figure 3] 3 is a diagram showing a manner in which the next step is performed after the step shown in FIG. 2 is performed. [Figure 4] FIG. 3 is a diagram showing a state in which the folding of the sealing portion is performed through the same steps as in FIG. 2, contact heating is performed in the first heating step, and non-contact heating is performed in the second heating step. [Figure 5] FIG. 3 is a diagram showing a state in which the folding of the sealing portion is performed through the same steps as in FIG. 2, non-contact heating is performed in the first heating step, and contact heating is performed in the second heating step. DETAILED DESCRIPTION OF THE INVENTION

[0032] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings so that those skilled in the art can easily understand and practice the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

[0033] In order to clearly describe the present invention, parts that are not relevant to the description will be omitted and the same reference numerals will be used throughout the specification to refer to the same or similar components.

[0034] Furthermore, the terms and words used in this specification and claims should not be interpreted in a way that is limited to their ordinary and dictionary meanings, but should be interpreted in a way that is consistent with the technical idea of ​​the present invention, in accordance with the principle that the inventor himself / herself can appropriately define the concept of terms in order to explain the invention in the best possible way.

[0035] The present invention relates to a method and device for folding a sealing part of a pouch-type secondary battery in which a sealing part 1 protrudes laterally (left and right in FIG. 2) along the periphery of a pouch 2 containing an electrode assembly. Hereinafter, an embodiment of the present invention will be described in more detail with reference to the accompanying drawings.

[0036] First embodiment The present invention provides a method for folding the sealing portion 1 of a pouch-type secondary battery as a first embodiment.

[0037] The folding method according to the present invention includes a heating step and a folding step, and the heating step includes a non-contact heating step in which the sealing part 1 does not come into direct contact with a heat source.

[0038] The heating step is a process of heating the sealing unit 1 to a predetermined temperature, and is performed at least twice during the folding method provided in this embodiment, and at least one of the heating steps is a non-contact heating step in which the sealing unit 1 is heated by irradiating light from a heat lamp 11. The heat lamp 11 described here is considered to provide an output capable of heating the sealing unit 1 to a predetermined temperature and to be capable of irradiating light evenly over the entire sealing unit 1, since the heat lamp 11 can heat the sealing unit 1 by radiant heat.

[0039] 2 is a view showing a state in which the sealing part of the pouch-type secondary battery is folded in a state in which non-contact heating is performed in the heating step according to the present invention. , first folding stage , second folding stage <c>, second heating stage <d>FIG. 3 shows the state in which the step shown in FIG. 2 is performed, and the next step (third folding step) is performed. <e>, 4th folding stage <f>, taping stage <g>) is performed.

[0040] As shown in the drawing, in the folding method according to the present invention, each of the heating step and the folding step is repeated multiple times.

[0041] First heating stage< / g> < / f> < / e> < / d> < / c> This is done with the sealing part 1 open flat. Heating lamps 11 are placed on the upper and lower sides of the sealing part 1, and infrared rays are irradiated onto the upper and lower surfaces of the sealing part 1 to heat the sealing part 1 to a predetermined temperature.

[0042] Meanwhile, the infrared rays irradiated in this embodiment are preferably near-infrared rays, which belong to the shortest wavelength range. Near-infrared rays have wavelengths in the range of 750 nm to 4 μm, and have the advantage that they can heat up in a shorter time than mid-infrared or far-infrared rays and can ensure worker stability even during long-term exposure. While ultraviolet rays, which have a shorter wavelength, can be used instead of infrared rays for heating, the present application provides near-infrared rays as a heat source, as they have high heating efficiency and ensure stability. Therefore, the heating lamp may be a halogen lamp, LED lamp, diode lamp, or the like, which can irradiate near-infrared rays.

[0043] In this case, the sealing part 1 includes a layer made of a thermoplastic resin, which is polypropylene, so that when heat is applied, the flexibility of the sealing part 1 increases (it becomes more flexible).

[0044] Then, when the sealing unit 1 is heated to a predetermined temperature, a folding step is performed, which may be performed by a folding unit 20 included in a folding device, which will be described later.

[0045] The folding unit 20 includes fixing units 21 and 23 that fix the folding point of the sealing unit 1 when folding is performed, and pressure units 22 and 24 that press the sealing unit 1 in the folding direction. Therefore, the folding step of the sealing unit 1 is performed when the fixing units 21 and 23 support the sealing unit so that it is fixed, and the pressure units 22 and 24 slide to fold the sealing unit 1 at a predetermined point.

[0046] At this time, the folding step may be performed in accordance with the length and thickness of the sealing portion 1 and the number of folding steps. , second folding stage <c>, and the third folding stage shown in FIG. <e>, 4th folding stage <f>That is, the folding step may be selectively omitted, repeated, or added depending on the length and thickness of the sealing portion 1.

[0047] In each folding stage, the fixing parts 21, 23 and the pressure parts 22, 24 may be provided with different types of devices. In order to fold the sealing part 1 at a right angle, the fixing part 21 is provided in the form of a plate having a slit or hole, and when the sealing part enters the slit or hole, the pressure part 22 slides vertically, thereby folding the sealing part at a 90° angle.

[0048] In the second folding step, the fixing part 23 may be provided (in the form of a plate or block) to support the underside of the sealing part 1 so that the sealing part 1 can be folded at an angle of 180°, and the pressure part 24 may slide horizontally (left and right in FIG. 2) on the fixing part 23 to fold the sealing part 1 at an angle of 180°.

[0049] If the sealing part 1 cools down below a certain temperature during the folding step, the second heating step is started. <d>will be carried out.

[0050] Then the first folding stage The third folding step is similar to the above. <e>After the above, the fourth folding step is performed to maintain the folded pattern or adjust the folding angle. <f>is selectively performed.

[0051] Finally, after the folding step is completed, a taping step is performed in which a fixing tape 30 is attached to fix the folded sealing portion.

[0052] Meanwhile, in this embodiment, it has been described that two heating steps are performed during the folding step, but the heating step may be performed only once or additionally as needed during the folding step.

[0053] However, at least one of the multiple heating steps is a non-contact heating step in which the heating lamp 11 irradiates the sealing portion 1 with light to heat it (in this case, if the heating step is performed once, it is a non-contact heating step).

[0054] However, in order to apply an appropriate pressure when heating the sealing portion 1, the heating step may further include a contact heating step in which heated heating blocks 12a and 12b are brought into contact with the sealing portion 1 to heat it.

[0055] That is, the heating step provided in this embodiment is configured such that a contact heating step is performed followed by a non-contact heating step, or a non-contact heating step is performed followed by a contact heating step.

[0056] In this case, one of the contact heating step and the non-contact heating step is performed first, and then a part of the folding step is performed, and the other of the contact heating step and the non-contact heating step is performed first, and then the remaining part of the folding step is performed.

[0057] FIG. 4 is a diagram showing a state in which the sealing portion is folded through the same steps as FIG. 2, contact heating is performed in the first heating step, and non-contact heating is performed in the second heating step. FIG. 5 is a diagram showing a state in which the sealing portion is folded through the same steps as FIG. 2, non-contact heating is performed in the first heating step, and contact heating is performed in the second heating step.

[0058] That is, the heating step may be performed multiple times. As shown in FIG. 4, a contact heating step using heating blocks 12a and 12b may be performed first, followed by a part of the folding step. In this state, a non-contact heating step may be performed in which heating lamps 11 irradiate light onto sealing portion 1 to heat it, followed by the remaining folding steps.

[0059] Alternatively, as shown in FIG. 5, the non-contact heating step may be performed first, followed by a portion of the folding step, and then the contact heating step may be performed again, followed by the remaining portion of the folding step.

[0060] That is, the folding method provided in the first embodiment may include one or more non-contact heating steps while multiple heating steps are performed, and may also include a contact heating step optionally.

[0061] Second embodiment The present invention provides a device for folding the sealing part 1 of a pouch-type secondary battery as a second embodiment. The folding device according to the present invention is a folding device for folding the sealing part of a pouch-type secondary battery in which the sealing part protrudes in a lateral direction of a pouch containing an electrode assembly, and includes a heating unit and a folding unit 20.

[0062] The heating unit is configured to heat the sealing unit 1 at a predetermined temperature and includes heating lamps 11 that irradiate light onto the sealing unit 1 to heat it, and the heating lamps 11 are arranged on the upper and lower sides of the sealing unit 1, respectively, to heat the upper and lower surfaces of the sealing unit 1 simultaneously.

[0063] More specifically, the heating unit provided in this embodiment may further include heating blocks 12a and 12b in addition to the heating lamp 11 that irradiates light onto the sealing unit to heat it.

[0064] The heating blocks 12a and 12b include an upper mold 12a and a lower mold 12b that can slide to move away from or approach each other, and at least one of the upper mold 12a and the lower mold 12b is heated to a predetermined temperature, and when the sealing part 1 enters between the upper mold 12a and the lower mold 12b, it comes into contact with and heats the sealing part 1. At this time, the upper mold 12a and the lower mold 12b may apply an appropriate pressure to the sealing part 1.

[0065] The heating lamp 11 and the heating blocks 12a and 12b are configured to be slidable so that their positions can be changed relative to each other.

[0066] At the same time, the folding unit 20 is configured to pressurize and fold the heated sealing unit 1. As described above, the folding unit includes fixing units 21 and 23 that fix the folding point of the sealing unit when folding is performed, and pressure units 22 and 24 that pressurize the sealing unit 1 in the folding direction.

[0067] The fixing parts 21 and 23 may be provided in the form of a plate having a slit or hole for the sealing part to enter (as described above) so as to efficiently fix the sealing part according to the length, thickness and number of folding times of the sealing part 1. Alternatively, the fixing parts may be provided in the form of a plate or block to support the bottom surface of the sealing part while it is folded 180°.

[0068] The pressure units 22 and 24 may be configured to be slidable so that appropriate pressure can be applied in various directions so that folding can be performed according to the rotational position of the sealing unit 1.

[0069] The present invention having the above technical features heats the sealing part 1 by irradiating infrared rays from the heating lamp 11, thereby eliminating the problem of the conventional method in which pressure acts on the sealing part 1 and causes damage.

[0070] Furthermore, since the heating temperature can be maintained uniformly compared to the conventional contact heating method, the sealing quality of the sealing part 1 can be maintained constant.

[0071] At the same time, in the present invention, contact heating may be performed by bringing heated heating blocks 12a and 12b into contact with the sealing part 1 to heat it, so that appropriate pressure can be applied to the sealing part 1 to heat it. In this case, since contact heating is performed before or after non-contact heating, the pressure applied to the sealing part 1 can be lower than in the conventional method, and therefore damage to the sealing part can be prevented.

[0072] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited thereto, and various implementations are possible within the technical spirit of the present invention and the scope of the claims set forth below by a person having ordinary skill in the art to which the present invention pertains. [Explanation of symbols]

[0073] 1 Sealing part 11 Heat Lamp 12a upper mold 12b Lower mold 20 Folding section 21, 23 Fixed part 22, 24 Pressurizing section< / f> < / e> < / d> < / f> < / e> < / c>

Claims

1. A method for folding a sealing part of a pouch-type secondary battery in which a sealing part protrudes toward a side of a pouch containing an electrode assembly, comprising: a sealing portion heating step of heating the sealing portion; a folding step of pressing and folding the heated sealing portion, The heating step of the sealing portion includes a non-contact heating step of using a heat lamp to irradiate light onto the sealing portion to heat it, The heating step of the sealing portion includes a contact heating step of contacting a heated heating block with the sealing portion to heat the sealing portion. How to fold the sealing part of a pouch-type secondary battery.

2. The method of claim 1 , wherein the sealing part includes a layer made of a thermoplastic resin.

3. The method of claim 2 , wherein the thermoplastic resin is polypropylene.

4. The method for folding a sealing part of a pouch-type secondary battery according to claim 1 , wherein the light irradiated by the heat lamp is infrared light.

5. The method of claim 1 , wherein the heating of the sealing portion is performed by performing a contact heating step and then a non-contact heating step.

6. The method of claim 1 , wherein the heating of the sealing part is performed by a contact heating step after a non-contact heating step.

7. One of the contact heating step and the non-contact heating step is performed first, and then a part of the folding step is performed, 7. The method of claim 5, wherein the remaining folding step is performed after the other of the contact heating step and the non-contact heating step is performed.

8. A method for folding a sealing portion of a pouch-type secondary battery in which the sealing portion protrudes in a lateral direction of a pouch containing an electrode assembly, comprising: a sealing portion heating step of heating the sealing portion; a folding step of pressing and folding the heated sealing portion, The heating step of the sealing portion includes a non-contact heating step of using a heat lamp to irradiate light onto the sealing portion to heat it, The heating step of the sealing portion includes a non-contact heating step in which the heating lamp irradiates the sealing portion with light to heat it, the non-contact heating step being performed multiple times; The non-contact heating step is first performed, and then a part of the folding step is performed, and in that state, the non-contact heating step is performed again, and then the remaining part of the folding step is performed. How to fold the sealing part of a pouch-type secondary battery.

9. 9. The method for folding a sealing part of a pouch-type secondary battery according to claim 1, further comprising a taping step of attaching a fixing tape to fix the folded sealing part after the folding step is completed.

10. A folding device for a pouch-type secondary battery sealing part, in which a sealing part protrudes in a lateral direction of a pouch containing an electrode assembly, a heating unit that heats the sealing unit; a folding unit that applies pressure to the heated sealing unit to fold it; the heating unit includes a heat lamp that irradiates light onto the sealing unit to heat it; The heating unit is The sealing device further includes an upper mold and a lower mold that are slidable to move away from or approach each other, at least one of the upper mold and the lower mold is heated at a predetermined temperature, and further includes a heating block that contacts and heats the sealing part when the sealing part enters between the upper mold and the lower mold, The heating lamp and the heating block are slidable so that their positions can be changed relative to each other. Folding device for the sealing part of pouch-type secondary batteries.

11. A folding device for a pouch-type secondary battery sealing portion, the sealing portion of which protrudes in a lateral direction of a pouch containing an electrode assembly, a heating unit that heats the sealing unit; a folding unit that applies pressure to the heated sealing unit to fold it; the heating unit includes a heat lamp that irradiates light onto the sealing unit to heat it; The folding portion is a fixing portion for fixing a folding point of the sealing portion when folding is performed; and a pressure unit that presses the sealing unit in the folding direction. Folding device for the sealing part of pouch-type secondary batteries.

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