Apparatus and method for folding sealing part of a pouch-type secondary battery

Abstract

The folding method according to the present invention is a method for folding a sealing portion of a pouch-type secondary battery in which a sealing portion protrudes laterally from a pouch containing an electrode assembly, and comprises: a sealing portion heating step of heating the sealing portion; and a folding step of pressing the heated sealing portion to fold it; wherein the heating step comprises a non-contact heating step in which a heating lamp irradiates light onto the sealing portion to heat it. A folding device according to the present invention is a folding device for a sealing portion of a pouch-type secondary battery in which a sealing portion protrudes laterally from a pouch containing an electrode assembly, and comprises: a heating portion for heating the sealing portion; and a folding portion for folding by applying pressure to the heated sealing portion. The heating portion includes a heating lamp that irradiates light onto the sealing portion to heat it, and the heating lamp is positioned at the upper and lower sides of the sealing portion, respectively, to simultaneously heat the upper and lower surfaces of the sealing portion.

Description

Technology Field

[0001] The present invention relates to a folding device and a folding method for folding a sealing portion formed along the edge of a pouch-type secondary battery, and more specifically, to a folding device and a folding method for a sealing portion of a pouch-type secondary battery that can resolve the problem of a conventional structure in which excessive pressure is applied to the sealing portion, causing damage to the sealing portion. Background Technology

[0003] The demand for secondary batteries as an energy source is rapidly increasing in various fields, including personal mobile devices and electric vehicles.

[0004] Unlike primary batteries, rechargeable secondary batteries are being developed not only for digital devices but also for transportation means such as electric vehicles.

[0005] While secondary batteries can be classified in various ways depending on the materials of the positive and negative electrodes and their external shape, lithium secondary batteries using lithium compounds are widely used as a replacement for conventional nickel-cadmium secondary batteries due to their high capacity and low self-discharge rate.

[0006] In addition, the above-mentioned lithium secondary battery can be manufactured in various forms, but it is generally manufactured in typical cylinder, prismatic, and pouch types.

[0007] Among these, the pouch-type secondary battery includes a pouch and an electrode assembly embedded in the pouch for charging and discharging electrical energy.

[0008] The electrode assembly is configured such that a cathode and an anode are alternately stacked together with a separator, and the electrode tabs, which consist of a cathode tab protruding from the cathodes and an anode tab protruding from the anodes, are joined to an electrode lead, and one end of the electrode lead is manufactured to protrude outside the pouch. At this time, depending on the manufacturing method of the anode and cathode, the anode tab and the cathode tab may be positioned on opposite sides of each other, or they may be positioned spaced apart from each other on the same side.

[0009] Meanwhile, the above pouch is manufactured with a structure that can be separated into two parts (e.g., a structure that can be separated into an upper and a lower part) so as to cover and accommodate one side and the other side of the electrode assembly, and when the electrode assembly and electrolyte are loaded inside, the two separated parts are joined to form a sealing part (1).

[0010] For example, the above pouch (2) may be manufactured such that the upper and lower portions each have grooves formed in a shape that is recessed to a predetermined size so as to accommodate an electrode assembly, and the edges of the grooves are formed flat along the perimeter.

[0011] Accordingly, after the electrode assembly is mounted, when the upper and lower parts of the pouch (2) are closed, the edges of each other come into contact, and in that state, a sealing part (1) is formed along the edge of the pouch (2) so that they are heat-fused to each other to form a seal.

[0012] Referring to FIG. 1, which shows the folding of the sealing portion of a pouch-type secondary battery according to a conventional method, the sealing portion (1) of the pouch (2) is heated through heating blocks (3a, 3b). The heating blocks (3a, 3b) are composed of an upper mold (3a) and a lower mold (3b) that can slide apart from or close to each other, and the upper mold (3a) and the lower mold (3b) are provided in a state heated to a predetermined temperature.

[0013] Then, when the sealing portion (1) enters between the upper mold (3a) and the lower mold (3b), the upper mold (3a) and the lower mold (3b) press and heat the sealing portion (1) from top to bottom to heat-fuse the sealing portion (1). Then, while the lower mold (3b) supports the sealing portion (1) from below, the upper mold (3a) slides sideways (left and right directions in FIG. 1) to fold the sealing portion (1). Alternatively, the sealing portion (1) may be folded through a separate folding device (not shown) after being removed from the heating block.

[0014] However, the heating method using pressure of the upper mold (3a) and lower mold (3b) as described above had the potential to cause damage, such as insulation breakdown, to the synthetic resin layer made of thermoplastic resin contained in the pouch (1). In addition, as the heating blocks (3a, 3b) were used repeatedly, temperature variations occurred, making it difficult to maintain sealing quality. The problem to be solved

[0016] Accordingly, the primary objective of the present invention is to provide a folding device and a folding method for a pouch-type secondary battery sealing portion that resolve the problem of the synthetic resin layer being damaged by pressure generated by direct contact when heating the sealing portion, and can heat the sealing portion while maintaining a uniform temperature. means of solving the problem

[0018] The present invention, for achieving the aforementioned objectives, provides a method for folding a sealing portion of a pouch-type secondary battery and a folding device, wherein the sealing portion protrudes laterally (left-right direction based on the drawing) along the circumference of a pouch containing an electrode assembly.

[0019] The folding method according to the present invention is a method for folding a sealing portion of a pouch-type secondary battery, comprising: a sealing portion heating step for heating the sealing portion; and a folding step for folding the heated sealing portion by applying pressure; wherein the heating step comprises a non-contact heating step in which a heating lamp irradiates light onto the sealing portion to heat it.

[0020] The above sealing portion includes a layer made of a thermoplastic resin, wherein the thermoplastic resin is polypropylene.

[0021] The light emitted from the above heating lamp is infrared.

[0022] The above heating step further includes a contact heating step in which a heated heating block is brought into contact with a sealing part to heat it.

[0023] The above heating step is configured such that a non-contact heating step proceeds after a contact heating step is performed, or a contact heating step proceeds after a non-contact heating step is performed.

[0024] At this time, either the contact heating step or the non-contact heating step is performed first, followed by a portion of the folding step, and after the other of the contact heating step or the non-contact heating step is performed, the remainder of the folding step is carried out.

[0025] The above heating step involves a non-contact heating step in which a heating lamp irradiates light onto the sealing part to heat it, which is performed multiple times; wherein the non-contact heating step is performed first, followed by a portion of the folding step, and then the non-contact heating step is performed again in that state, after which the remaining process of the folding step is carried out.

[0026] And, after the folding step is completed, a taping step is included in which a fixing tape is attached to secure the folded sealing part.

[0027] A folding device according to the present invention is a folding device for a sealing portion of a pouch-type secondary battery in which a sealing portion protrudes laterally from a pouch containing an electrode assembly, and comprises: a heating portion for heating the sealing portion; and a folding portion for folding by applying pressure to the heated sealing portion. The heating portion includes a heating lamp that irradiates light onto the sealing portion to heat it. At this time, the heating lamp is positioned at the upper and lower sides of the sealing portion, respectively, to simultaneously heat the upper and lower surfaces of the sealing portion.

[0028] The heating unit further includes an upper mold and a lower mold that can slide apart from or close to each other, and at least one of the upper mold and the lower mold is heated to a predetermined temperature, and a heating block that contacts and heats the sealing part when the sealing part enters between the upper mold and the lower mold. At this time, the heating lamp and the heating block are configured to slide so that their positions can be changed.

[0029] The above folding part includes a fixing part that fixes the bending point of the sealing part when folding is performed; and a pressing part that presses the sealing part in the direction in which folding is performed. Effects of the invention

[0031] The present invention, having the technical features described above, can resolve the conventional problem in which damage occurs to the sealing part due to pressure acting on it (by direct contact with the heating block) because heating is achieved by irradiating infrared rays from a heating lamp to the sealing part.

[0032] In addition, compared to conventional contact heating methods, the heating temperature can be maintained uniformly, allowing the sealing quality of the sealing part to be maintained consistently.

[0033] Furthermore, in the present invention, contact heating can be performed by bringing a heated heating block into contact with the sealing part, thereby allowing heating while applying appropriate pressure to the sealing part. At this time, since contact heating is performed additionally before or after non-contact heating, the pressure applied to the sealing part can be reduced compared to conventional methods. Therefore, damage to the sealing part can be prevented. Brief explanation of the drawing

[0035] FIG. 1 is a drawing showing the folding of a sealing portion of a pouch-type secondary battery according to a conventional method. FIG. 2 is a drawing showing the folding of a pouch-type secondary battery sealing portion in a state where non-contact heating is performed during the heating step according to the present invention. FIG. 3 is a diagram showing the subsequent steps being performed after the steps shown in FIG. 2 have been performed. FIG. 4 is a drawing showing that the folding of the sealing portion is performed through the same steps as FIG. 2, wherein contact heating is performed in the first heating step and non-contact heating is performed in the second heating step. FIG. 5 is a drawing showing that the folding of the sealing portion is performed through the same steps as FIG. 2, wherein non-contact heating is performed in the first heating step and contact heating is performed in the second heating step. Specific details for implementing the invention

[0036] Hereinafter, the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement it. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0037] To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0038] Furthermore, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0039] The present invention relates to a method for folding a sealing portion and a folding device for a pouch-type secondary battery in which a sealing portion (1) protrudes laterally (left and right directions based on FIG. 2) along the circumference of a pouch (2) containing an electrode assembly. Hereinafter, embodiments according to the present invention will be described in more detail with reference to the attached drawings.

[0041] First embodiment

[0043] The present invention provides a method for folding a sealing portion (1) of a pouch-type secondary battery as a first embodiment.

[0044] The folding method according to the present invention comprises a heating step and a folding step, wherein the heating step includes a non-contact heating step in which direct contact between the sealing part (1) and the heat source does not occur.

[0045] The heating step described above is a process of heating the sealing part (1) to a predetermined temperature, and is performed at least twice during the folding method provided in this embodiment, wherein at least one of the steps is a non-contact heating step in which light is irradiated from a heating lamp (11) to the sealing part (1) to heat it. The heating lamp (11) described herein is considered to provide an output capable of heating the sealing part (1) to a predetermined temperature and to irradiate light evenly over the entire sealing part (1) so as to be able to heat the sealing part (1) through radiant heat.

[0046] FIG. 2 is a drawing including a view in which folding of a pouch-type secondary battery sealing portion is performed while non-contact heating is performed in the heating step according to the present invention. That is, FIG. 2 shows the first heating step , 1st folding stage , second folding stage <c>, second heating stage <d>FIG. 3 is a drawing illustrating the progress of the process, and FIG. 3 shows the subsequent steps (third folding step) after the steps shown in FIG. 2 have been completed. <e>, 4th folding stage <f>, taping stage <g>This is a drawing showing the process of ) taking place.

[0047] As shown in the drawing, the folding method according to the present invention performs the heating step and the folding step by repeating each of them multiple times.

[0048] First heating stage< / g> < / f> < / e> < / d> < / c> This is done when the sealing portion (1) is spread flat. With the heating lamp (11) positioned on the upper and lower sides of the sealing portion (1), the sealing portion (1) is heated to a predetermined temperature by irradiating infrared rays onto the upper and lower surfaces of the sealing portion (1).

[0049] Meanwhile, in this embodiment, it is preferable that the infrared radiation irradiated is near-infrared radiation belonging to the shortest wavelength region. Near-infrared radiation is infrared radiation with a wavelength in the range of 750 nm to 4 µm, and has the advantage of being able to heat up in a relatively short time compared to mid-infrared or far-infrared radiation, and ensuring the safety of the worker even during long-term exposure. Although heating may be achieved by irradiating ultraviolet radiation with a shorter wavelength instead of infrared radiation, the safety of the worker cannot be guaranteed when using ultraviolet radiation; therefore, the present invention provides near-infrared radiation as a heat source, which has high heating efficiency and ensures safety. Accordingly, the heating lamp may be a halogen lamp, LED lamp, diode lamp, etc., capable of irradiating near-infrared radiation.

[0050] At this time, the sealing portion (1) includes a layer made of a thermoplastic resin, wherein the thermoplastic resin is polypropylene. Therefore, when heat is applied, the flexibility of the sealing portion (1) increases (becomes more flexible).

[0051] And, when the sealing part (1) is heated to a predetermined temperature, a folding step is performed. The folding step can be performed by a folding part (20) included in a folding device to be described later.

[0052] The folding part (20) includes a fixing part (21, 23) that fixes the bending point of the sealing part (1) when folding is performed, and a pressing part (22, 24) that presses the sealing part (1) in the direction in which folding is performed. Accordingly, while the fixing part (21, 23) supports the sealing part so that it is fixed, the pressing part (22, 24) slides so that a predetermined point of the sealing part (1) bends, thereby performing the folding step of the sealing part (1).

[0053] At this time, the folding step is the first folding step shown in FIG. 2 according to the length and thickness of the sealing part (1) and the number of foldings. , second folding stage <c>and the third folding step shown in FIG. 3 <e>, 4th folding stage <f>It can be performed in multiple steps. That is, the folding steps may be selectively deleted, repeated, or added depending on the length and thickness of the sealing part (1).

[0054] Also, depending on each folding step, the fixing part (21, 23) and the pressing part (22, 24) may be provided with different types of devices. For example, the first folding step In order to bend the sealing part (1) at a right angle, the fixing part (21) is provided in the form of a plate with a slit or a hole, so that when the sealing part enters the slit or hole, the pressing part (22) slides in a vertical direction, thereby allowing the sealing part to be folded at a 90° angle.

[0055] In addition, in the second folding stage, the fixing part (23) can be provided (in the form of a plate or block) to support the lower surface of the sealing part (1) so that the sealing part (1) can be folded 180°, and the pressing part (24) can slide horizontally (left and right direction in FIG. 2) over the fixing part (23) to fold the sealing part (1) at an angle of 180°.

[0056] If the sealing part (1) cools down to a temperature below a certain level while the folding step is in progress, the second heating step <d>...is accomplished.

[0057] Next, the first folding stage The third folding stage in a similar manner <e>After this is done, the fourth folding step to maintain the shape of the folded part or to adjust the folding angle <f>It is done selectively.

[0058] Finally, after the folding step is completed, a taping step is performed to attach a fixing tape (30) so that the folded sealing part is fixed.

[0059] Meanwhile, although this embodiment describes two heating steps being performed during the folding step, the heating step may be added as needed or performed only once during the folding step.

[0060] However, at least one of the multiple heating steps is a non-contact heating step in which a heating lamp (11) irradiates light onto the sealing part (1) to heat it (at this time, when the heating step is performed once, it is a non-contact heating step).

[0061] However, in order to apply appropriate pressure when heating the sealing part (1), the heating step may further include a contact heating step in which the heated heating blocks (12a, 12b) are brought into contact with the sealing part (1) to heat it.

[0062] That is, the heating step provided in this embodiment is configured such that a non-contact heating step is performed after a contact heating step, or a contact heating step is performed after a non-contact heating step.

[0063] At this time, either the contact heating step or the non-contact heating step is performed first, followed by a portion of the folding step, and after the other of the contact heating step or the non-contact heating step is performed, the remainder of the folding step is carried out.

[0064] FIG. 4 is a drawing showing that the sealing part is folded through the same steps as FIG. 2, but contact heating is performed in the first heating step and non-contact heating is performed in the second heating step, and FIG. 5 is a drawing showing that the sealing part is folded through the same steps as FIG. 2, but non-contact heating is performed in the first heating step and contact heating is performed in the second heating step.

[0065] That is, the heating step is performed multiple times, but as shown in FIG. 4, a contact heating step through the heating blocks (12a, 12b) is performed first, followed by some of the folding steps, and then a non-contact heating step is performed in which a heating lamp (11) irradiates light onto the sealing part (1) to heat it, and then the remaining steps of the folding step can be performed sequentially.

[0066] Alternatively, as shown in FIG. 5, a non-contact heating step may be performed first, followed by some of the folding steps, and then a contact heating step may be performed again, after which the remaining steps of the folding step may be performed.

[0067] That is, the folding method provided in the first embodiment comprises at least one non-contact heating step during the process of multiple heating steps, and may also optionally include a contact heating step.

[0069] Second embodiment

[0071] The present invention provides a device for folding a sealing portion (1) of a pouch-type secondary battery as a second embodiment. The folding device according to the present invention is a folding device for a sealing portion of a pouch-type secondary battery in which the sealing portion protrudes laterally from a pouch containing an electrode assembly, and comprises a heating portion and a folding portion (20).

[0072] The heating unit is configured to heat the sealing unit (1) to a predetermined temperature and includes a heating lamp (11) that heats the sealing unit (1) by irradiating light onto it, and the heating lamp (11) is positioned at the upper and lower sides of the sealing unit (1) respectively to heat the upper and lower surfaces of the sealing unit (1) simultaneously.

[0073] More specifically, the heating unit provided in this embodiment may further include heating blocks (12a, 12b) in addition to a heating lamp (11) that heats the sealing unit by irradiating light onto it.

[0074] The heating blocks (12a, 12b) include an upper mold (12a) and a lower mold (12b) that can slide apart from or close to each other, and at least one of the upper mold (12a) and the lower mold (12b) is heated to a predetermined temperature so that when a 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) can apply appropriate pressure to the sealing part (1).

[0075] Also, the heating lamp (11) and the heating block (12a, 12b) are configured to slide so that their positions can be changed.

[0076] In addition, the folding part (20) is configured to fold by applying pressure to the heated sealing part (1). As described above, the folding part includes a fixing part (21, 23) that fixes the bending point of the sealing part when folding is performed, and a pressing part (22, 24) that applies pressure to the sealing part (1) in the direction in which folding is performed.

[0077] The above fixing part (21, 23) may be provided in the form of a plate with a slit or hole so that the sealing part can enter (as described above) in order to efficiently fix the sealing part according to the length and thickness of the sealing part (1) and the number of foldings. Alternatively, the above fixing part may be provided in the form of a plate or block so that it can support the bottom surface while the sealing part is folded 180°.

[0078] Also, the pressurizing part (22, 24) can be configured to slide so that appropriate pressure is applied in various directions so that folding can be achieved according to the rotational position of the sealing part (1).

[0080] The present invention, having the technical features described above, can resolve the problem of the conventional method in which pressure is applied to the sealing part (1) and damage occurs because heating is achieved by irradiating infrared rays from the heating lamp (11) to the sealing part (1).

[0081] In addition, compared to conventional contact heating methods, the heating temperature can be maintained uniformly, so the sealing quality of the sealing part (1) can be maintained consistently.

[0082] In addition, in the present invention, contact heating can be performed by bringing the heated heating blocks (12a, 12b) into contact with the sealing part (1), thereby allowing heating while applying appropriate pressure to the sealing part (1). At this time, since contact heating is performed additionally before and after non-contact heating, the pressure applied to the sealing part (1) can be reduced compared to the conventional method. Therefore, damage to the sealing part can be prevented.

[0083] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and various implementations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0085] 1 : Sealing part 11 : Heating lamp 12a : Hieroglyph 12b : Lower type 20 : Folding part 21, 23: Fixed part 22, 24: Pressurized section< / f> < / e> < / d> < / f> < / e> < / c>

Claims

Claim 1 A method for folding a sealing portion of a pouch-type secondary battery, wherein the sealing portion protrudes laterally from a pouch containing an electrode assembly, comprising: a sealing portion heating step for heating the sealing portion; and a folding step for folding the heated sealing portion by applying pressure; wherein the heating step includes a non-contact heating step in which a heating lamp irradiates light onto the sealing portion to heat it; wherein the heating step is performed multiple times, wherein a non-contact heating step in which a heating lamp irradiates light onto the sealing portion to heat it is performed first, and then a part of the folding step is performed, and then the non-contact heating step is performed again in that state, and then the remaining process of the folding step is performed. Claim 2 A folding method for a pouch-type secondary battery sealing portion according to claim 1, characterized in that the sealing portion comprises a layer made of a thermoplastic resin. Claim 3 A folding method for a pouch-type secondary battery sealing portion, characterized in that, in claim 2, the thermoplastic resin is polypropylene. Claim 4 A folding method for a pouch-type secondary battery sealing portion, characterized in that, in claim 1, the light irradiated from the heating lamp is infrared. Claim 5 A folding method for a pouch-type secondary battery sealing portion according to claim 1, wherein the heating step comprises a contact-type heating step in which a heated heating block is brought into contact with the sealing portion to heat it. Claim 6 In claim 5, the heating step is a folding method for a pouch-type secondary battery sealing part in which a non-contact heating step is performed after a contact heating step is performed. Claim 7 In claim 5, the heating step is a folding method for a pouch-type secondary battery sealing part in which a contact heating step is performed after a non-contact heating step. Claim 8 A folding method for a pouch-type secondary battery sealing portion according to claim 6 or 7, wherein either the contact heating step or the non-contact heating step is performed first, followed by a portion of the folding step, and the other of the contact heating step or the non-contact heating step is performed, followed by the remainder of the folding step. Claim 9 delete Claim 10 A method for folding a sealing portion of a pouch-type secondary battery, comprising: a taping step of attaching a fixing tape to secure the folded sealing portion after the folding step is completed, in any one of claims 1 to 7. Claim 11 delete Claim 12 delete Claim 13 delete

Images