Bag sealing apparatus capable of targeting heating portion

Abstract

A structure of a sealing apparatus is provided that includes a pair of sealing tool assemblies including an exothermic sealing tool, an endothermic sealing tool, and an endothermic / exothermic device. The heat release sealing means and the heat absorption sealing means each extend in a width direction of the bag and are juxtaposed to each other in a length direction of the bag. An endothermic / exothermic device is interposed between the exothermic sealing tool and the endothermic sealing tool to radiate heat to the exothermic sealing tool and absorb heat from the endothermic sealing tool.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0173079, filed on December 12, 2022, and Korean Patent Application No. 10-2023-0066867, filed on May 24, 2023, and the entire contents disclosed in these patent application documents are incorporated herein by reference as part of this specification.

[0002] The present invention relates to a sealing device for fusion-sealing a pouch for accommodating an electrode assembly in a pouch-type battery cell. Background Art

[0003] Secondary batteries that provide application convenience according to product groups and have electrical characteristics such as high energy density are widely used not only in portable devices but also in electric vehicles or hybrid vehicles driven by an electric drive source.

[0004] These secondary batteries are attracting attention as new energy sources for improving eco-friendliness and energy efficiency, not only because they have the main advantage of significantly reducing the use of fossil fuels but also because they do not produce any by-products due to energy use.

[0005] Currently and widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these secondary battery cells, i.e., the operating voltage of a single battery cell, is approximately 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack can be manufactured by connecting multiple battery cells in series. Additionally, according to the charge and discharge capacity required for the battery pack, a battery pack can be manufactured by connecting multiple battery cells in parallel. Therefore, the number of battery cells included in the battery pack and the type of electrical connection can be selected in various ways according to the required output voltage and / or charge and discharge capacity.

[0006] Meanwhile, generally, according to the shape of the battery case, secondary batteries are divided into: cylindrical batteries and prismatic batteries, in which the electrode assemblies are respectively built into cylindrical metal cans or prismatic metal cans; and pouch-type batteries, in which the electrode assemblies are built into a pouch-type case made of a pouch film of a metal foil material.

[0007] Figure 1 is a perspective view illustrating the structure of a pouch-type battery cell, and Figure 2 is a cross-sectional view illustrating the sealed portion of a pouch-type battery cell. Refer to Figure 1 and Figure 2, the pouch-type battery cell is manufactured by accommodating the electrode assembly 11 in a pouch 14 made of a metal sheet material, where the electrode assembly 11 has a plurality of electrodes and separators stacked alternately therein. The pouch 14 surrounds the electrode assembly 11 and is sealed at a first sealing portion 143a and a second sealing portion 143b. The electrode tab 12 extends from the plurality of electrodes and is welded to the electrode lead 13, and the electrode lead 13 protrudes from the pouch 14 through the first sealing portion 143a. Here, a lead film 131 made of a thermoplastic synthetic resin provided on the electrode lead 13 is interposed between the pouch 14 and the electrode lead 13.

[0008] Figure 3 is an enlarged cross-sectional view showing the structure of the insulating layer of the pouch. Referring to Figure 3 , the pouch 14 includes a metal layer 141 and an inner insulating layer 142a and an outer insulating layer 142b respectively coated on the inner and outer surfaces of the metal layer 141. Each of the inner insulating layer 142a and the outer insulating layer 142b includes a thermoplastic synthetic resin, and the inner insulating layer 142a insulates the electrode assembly 11 and the electrode tab 12 from the metal layer 141, and the outer insulating layer 142b insulates the outside of the pouch 14 from the metal layer 141.

[0009] Figure 4 and Figure 5 illustrate the structure and arrangement of a conventional sealing device. Referring to Figure 4 and Figure 5 , the sealing device 2 is used to seal the pouch 14. Hereinafter, the sealing device for forming the first sealing portion 143a will be exemplified. However, the same applies to the second sealing portion 143b.

[0010] The sealing device 2 includes a sealing tool 21 that applies pressure and heat at the location where the first sealing portion 143a is to be formed, a sealing block 22 connected to the sealing tool 21, an insulating frame 24 that houses the sealing block 22, and a heating rod 23 inserted into the sealing block 22. A pair of sealing devices 2 are provided above and below the location where the first sealing portion 143a is to be formed. Here, the sealing tool 21 is provided with a groove 211 having a shape corresponding to the electrode lead 13.

[0011] Figure 6 is a cross-sectional view showing the Figure 4 sealing device sealing the pouch. When the heating rod 23 heats the sealing block 22, the sealing tool 21 is heated through the sealing block 22, and the sealing tool 21 applies pressure and heat at the location where the first sealing portion 143a is to be formed, thereby fusing the inner insulating layer 142a and the lead film 131 to seal the pouch 14.

[0012] Meanwhile, the melting point of the polypropylene resin, which is mainly used as the material for the inner insulating layer 142a and the lead film 131, is approximately 160 degrees Celsius. Therefore, the sealing tool 21 must be heated to a temperature higher than 160 degrees Celsius. When performing the sealing, not only is the thermal energy of the sealing tool 21 directly conducted to the location where the first sealing portion 143a is to be formed, but also the conducted heat that conducts along the metal layer 141 from the first sealing portion 143a and the radiant heat and convective heat that are conducted from the sealing tool 21 to the bag 14 can reach portions of the bag 14 other than the location where the first sealing portion 143a is to be formed. Such conducted heat, radiant heat, and convective heat may cause the insulating layer 142 to melt and result in damage, and thus there is a risk that the insulating performance of the bag 14 may be reduced.

[0013] In addition, since the sealing tool 21 is directly exposed to the air, thermal energy is lost in the form of radiant heat and convective heat, and the energy efficiency is reduced. Summary of the Invention

[0014] Technical Problem

[0015] In order to solve the above problems of the prior art, an object of the present invention is to provide a structure of a sealing device that can minimize heat conduction to portions other than the portion to be sealed when sealing a bag.

[0016] Another object of the present invention is to provide a structure of a sealing device that can improve the insulating performance of a battery cell and reduce the defect rate by preventing damage to the inner insulating layer and the outer insulating layer of the bag.

[0017] Still another object of the present invention is to provide a structure of a sealing device that can cool portions other than the portion to be sealed to below room temperature during sealing.

[0018] Still another object of the present invention is to provide a structure of a sealing device that can accurately target the portion to be heated during sealing, thereby heating only the desired portion without heating other portions.

[0019] Still another object of the present invention is to provide a structure of a sealing device that can minimize heat loss and improve energy efficiency.

[0020] Still another object of the present invention is to provide a structure of a sealing device that can quickly heat the portion to be heated to a high temperature and maintain the heated portion at a constant temperature.

[0021] Still another object of the present invention is to provide a sealing device having a simple structure and manufactured with the fewest number of parts.

[0022] The technical problems to be solved by the present invention are not limited to the above objects, and other objects and advantages not described in the present invention can be understood through the following description and will be more clearly understood through the examples of the present invention. Additionally, it is obvious that the objects and advantages of the present invention can be embodied by the means and their combinations pointed out in the claims.

[0023] Technical solution

[0024] To solve the above problems, the present invention provides a structure of a sealing device, the sealing device including a pair of sealing tool assemblies, the pair of sealing tool assemblies including an exothermic sealing tool, an endothermic sealing tool, and an endothermic / exothermic device.

[0025] [First Embodiment]

[0026] The first embodiment of the present invention can be applied to a sealing device for forming, by welding, a first sealing portion along the width direction of the bag at two longitudinal ends of the bag of a pouch-type battery cell. The pouch-type battery cell may include electrode leads extending from the inside of the bag and protruding through the first sealing portion.

[0027] The exothermic sealing tool can extend along the width direction of the bag. The exothermic sealing tool can be provided with a first groove corresponding to the shape of the electrode lead.

[0028] According to the first embodiment of the present invention, the first groove can be formed by recessing a part of the width direction center of one height direction end of the exothermic sealing tool toward the other height direction end. The length of the first groove in the width direction of the bag can be equal to the width of the electrode lead, and the depth of the first groove can be equal to the thickness of the electrode lead or half of it.

[0029] The endothermic sealing tool can extend along the width direction of the bag. The endothermic sealing tool can be provided with a second groove corresponding to the shape of the electrode lead.

[0030] According to the first embodiment of the present invention, the second groove can be formed by recessing a part of the width direction center of one height direction end of the endothermic sealing tool toward the other height direction end. The length of the second groove in the width direction of the bag can be equal to the width of the electrode lead, and the depth of the second groove can be equal to the thickness of the electrode lead or half of it.

[0031] The endothermic sealing tool can be juxtaposed with the exothermic sealing tool along the length of the bag. Here, each sealing tool assembly can be provided with one endothermic sealing tool, or each sealing tool assembly can be provided with two or more endothermic sealing tools. When each sealing tool assembly is provided with one endothermic sealing tool, the endothermic sealing tool can be arranged more inward than the exothermic sealing tool in the length direction of the bag, and when each sealing tool assembly is provided with two endothermic sealing tools, the endothermic sealing tools can be arranged on two lengthwise sides of the exothermic sealing tool.

[0032] The endothermic / exothermic device can be interposed between the exothermic sealing tool and the endothermic sealing tool, while radiating heat to the exothermic sealing tool and absorbing heat from the endothermic sealing tool respectively. For example, when an electric current is applied, the endothermic / exothermic device can radiate heat through the first side of the endothermic / exothermic device and absorb heat through the second side opposite to the first surface of the endothermic / exothermic device, and the endothermic / exothermic device can be interposed between the exothermic sealing tool and the endothermic sealing tool, wherein the first side is in contact with the exothermic sealing tool and the second side is in contact with the endothermic sealing tool.

[0033] A plurality of endothermic / exothermic devices can be arranged to be in contact with the wider surface of the exothermic sealing tool and the wider surface of the endothermic sealing tool. Specifically, a plurality of endothermic / exothermic devices arranged in a grid form can be arranged to be in contact with the surface of the exothermic sealing tool and the surface of the endothermic sealing tool parallel to the length direction of the bag.

[0034] According to the first embodiment of the present invention, the endothermic / exothermic device can include a thermoelectric element, which radiates heat through the first surface of the thermoelectric element and absorbs heat through the second surface opposite to the first surface of the thermoelectric element when an electric current is applied. The thermoelectric element is a semiconductor device, which includes multiple pairs of P-type semiconductors and N-type semiconductors connected in electrical series and thermal parallel and can maintain a constant temperature difference between the first side and the second side when a constant DC voltage is applied.

[0035] The sealing tool assembly can further include an insulating plate, which is arranged in the space between the exothermic sealing tool and the endothermic sealing tool where no endothermic / exothermic device is provided. The insulating plate can include an insulating material.

[0036] According to the first embodiment of the present invention, the insulating plate includes a plate made of an insulating material and is interposed between the exothermic sealing tool and the endothermic sealing tool. The insulating plate can be provided with through holes for mounting the endothermic / exothermic device therein.

[0037] The sealing device of the present invention may further include a pair of insulating frames that respectively accommodate the pair of sealing tool assemblies. Each of the insulating frames may have five closed side portions that respectively cover five side portions of each of the sealing tool assemblies in the sealing tool assembly except for the first height-direction end portion and the second height-direction end portion that respectively face the first sealing portion.

[0038] [Second Embodiment]

[0039] The second embodiment of the present invention may be applied to a sealing device that forms a first sealing portion along the length direction of a bag at one width-direction end of a bag of a pouch-type battery cell by welding. The pouch-type battery cell may include electrode leads that extend from the inside of the bag and protrude through the first sealing portion.

[0040] The exothermic sealing tool may extend along the length direction of the bag.

[0041] The endothermic sealing tool may extend along the length direction of the bag.

[0042] The endothermic sealing tool may be juxtaposed with the exothermic sealing tool along the width direction of the bag. Here, each sealing tool assembly may be provided with one endothermic sealing tool, or each sealing tool assembly may be provided with two or more endothermic sealing tools. When each sealing tool assembly is provided with one endothermic sealing tool, the endothermic sealing tool may be disposed more inward in the width direction of the bag than the exothermic sealing tool, and when each sealing tool assembly is provided with two endothermic sealing tools, the endothermic sealing tools may be disposed on two width-direction sides of the exothermic sealing tool.

[0043] The endothermic / exothermic device may be interposed between the exothermic sealing tool and the endothermic sealing tool while radiating heat to the exothermic sealing tool and absorbing heat from the endothermic sealing tool respectively. For example, when an electric current is applied, the endothermic / exothermic device may radiate heat through the first side portion of the endothermic / exothermic device and absorb heat through the second side portion opposite to the first surface of the endothermic / exothermic device, and the endothermic / exothermic device may be interposed between the exothermic sealing tool and the endothermic sealing tool, wherein the first side portion is in contact with the exothermic sealing tool and the second side portion is in contact with the endothermic sealing tool.

[0044] A plurality of endothermic / exothermic devices may be arranged to be in contact with the wider surface of the exothermic sealing tool and the wider surface of the endothermic sealing tool. Specifically, a plurality of endothermic / exothermic devices arranged in a grid pattern may be arranged to be in contact with the surface of the exothermic sealing tool and the surface of the endothermic sealing tool parallel to the length direction of the bag.

[0045] According to a second embodiment of the present invention, the heat absorption / exotherm device may include a thermoelectric element which, when a current is applied, radiates heat through a first surface of the thermoelectric element and absorbs heat through a second surface of the thermoelectric element opposite to the first surface. The thermoelectric element is a semiconductor device which includes a plurality of pairs of P-type semiconductors and N-type semiconductors connected in electrical series and thermal parallel and which can maintain a constant temperature difference between a first side portion and a second side portion when a constant DC voltage is applied.

[0046] The sealing tool assembly may further include an insulating plate disposed in a space between the exothermic sealing tool and the endothermic sealing tool where the heat absorption / exotherm device is not provided. The insulating plate may include an insulating material.

[0047] According to a second embodiment of the present invention, the insulating plate includes a plate made of an insulating material and is interposed between the exothermic sealing tool and the endothermic sealing tool. The insulating plate may be provided with a through hole in which the heat absorption / exotherm device is installed.

[0048] The sealing device of the present invention may further include a pair of insulating frames respectively accommodating the pair of sealing tool assemblies. Each of the insulating frames may have five closed side portions respectively covering five side portions of each of the sealing tool assemblies in the sealing tool assembly except for a first height direction end portion and a second height direction end portion thereof respectively facing the first sealing portion.

[0049] Advantageous Effects

[0050] The present invention can provide a structure of a sealing device which can use an endothermic sealing tool to prevent battery cell defects and improve performance. When the exothermic sealing tool heats the sealing portion, the endothermic sealing tool absorbs heat from the bag except for the sealing portion of the bag, thereby preventing heat transfer to portions other than the sealing portion and preventing damage to the insulating layer.

[0051] In addition, by using the thermoelectric element, the present invention can provide a structure of a sealing device with high efficiency by directly transferring the thermal energy absorbed by the endothermic sealing tool to the exothermic sealing tool, and a structure of a sealing device with a simple structure capable of being heated to above 150 degrees Celsius and cooled to room temperature or below only by applying a voltage.

[0052] The sealing device according to a second embodiment of the present invention can only concentrate on heating and sealing a desired area by juxtaposing the endothermic sealing tool on both sides of the exothermic sealing tool.

[0053] The advantages of the present invention also lie in that the present invention can provide a structure of a sealing device with minimum heat loss by covering five side portions of the exothermic sealing tool except for one side portion facing the sealing portion with the endothermic sealing tool, the insulating plate and the insulating frame.

[0054] Another advantage of the present invention is that the present invention can provide a structure of a sealing device capable of quickly heating and cooling and maintaining a constant temperature by arranging a plurality of heat absorption / exotherm devices in contact with the wider surface of the exothermic sealing tool and the wider surface of the heat absorption sealing tool.

[0055] In addition, the present invention can have various other effects, and descriptions of various other effects will be given in each embodiment, or descriptions of effects that can be easily inferred by those skilled in the art will be omitted. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is a perspective view illustrating the structure of a pouch-type battery cell, and Figure 2 is a cross-sectional view illustrating the first sealing portion of the pouch-type battery cell.

[0057] Figure 3 is an enlarged cross-sectional view illustrating the structure of the insulating layer of the pouch.

[0058] Figure 4 and Figure 5 illustrate the structure and arrangement of a conventional sealing device.

[0059] Figure 6 is an illustration of Figure 4 a cross-sectional view of the sealing device sealing the pouch.

[0060] Figure 7 and Figure 8 are an exploded perspective view and a perspective view respectively illustrating the structure of a sealing tool assembly according to a first embodiment of the present invention.

[0061] Figure 9 and Figure 10 illustrate the structure of a thermoelectric element and the heating and cooling operations of the thermoelectric element according to a first embodiment of the present invention, respectively.

[0062] Figure 11 illustrates the sealing tool assembly accommodated in an insulating frame according to a first embodiment of the present invention.

[0063] Figure 12 illustrates the arrangement of a sealing device according to a first embodiment of the present invention.

[0064] Figure 13 is a cross-sectional view illustrating the sealing device according to a first embodiment of the present invention sealing the pouch.

[0065] Figure 14 illustrates the movement of heat when the sealing device seals the pouch according to a first embodiment of the present invention.

[0066] Figure 15And Figure 16 are an exploded perspective view and a perspective view respectively showing the structure of a sealing tool assembly according to a second embodiment of the present invention.

[0067] Figure 17 Shows a sealing tool assembly accommodated in an insulating frame according to a second embodiment of the present invention.

[0068] Figure 18 Shows the arrangement of a sealing device according to a second embodiment of the present invention.

[0069] Figure 19 Is a cross-sectional view of a sealing device for sealing a bag according to a second embodiment of the present invention.

[0070] [Description of reference numerals]

[0071] 1: Battery cell

[0072] 11: Electrode assembly

[0073] 12: Electrode tab

[0074] 13: Electrode lead

[0075] 131: Lead film

[0076] 14: Bag

[0077] 141: Metal layer

[0078] 142: Insulating layer

[0079] 142a: Inner insulating layer

[0080] 142b: Outer insulating layer

[0081] 143: Sealing portion

[0082] 143a: First sealing portion

[0083] 143b: Second sealing portion

[0084] 2: Sealing device 1

[0085] 21: Sealing tool

[0086] 211: Groove

[0087] 22: Sealing block

[0088] 221: First hole

[0089] 23: Heating rod

[0090] 24: Insulating frame

[0091] 241: Second hole

[0092] 3: Sealing device 2

[0093] 31: Exothermic sealing tool

[0094] 311: First groove

[0095] 32: Endothermic sealing tool

[0096] 321: Second groove

[0097] 33: Endothermic / exothermic device (Peltier element)

[0098] 34: Insulating plate

[0099] 35: Insulating frame

[0100] 4: Sealing device 3

[0101] 41: Exothermic sealing tool

[0102] 42: Endothermic sealing tool

[0103] 43: Endothermic / exothermic device (Peltier element)

[0104] 44: Insulating plate

[0105] 45: Insulating frame

[0106] X: Length direction

[0107] Y: Width direction

[0108] Z: Height direction / Thickness direction Detailed implementation manners

[0109] The above objects, features and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art will be able to implement the technical concept of the present invention. When determining that the detailed description of the prior art related to the present invention unnecessarily obscures the key points of the present invention, the detailed description thereof will be omitted. Below, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to represent the same or similar components.

[0110] Although "first", "second", etc. are used to describe various elements, these elements are of course not limited by these terms. These terms are only used to distinguish one element from another, and unless otherwise specifically stated, the first element may also be the second element.

[0111] Throughout the specification, unless otherwise stated, each element may be singular or plural.

[0112] Hereinafter, "arranging an element at an upper portion (or a lower portion) of an element" or "arranging an element at a top (or a bottom) of an element" not only means "arranging the element in contact with an upper surface (or a lower surface)", but also means "arranging the element above an upper surface (or a lower surface) in such a manner that another element is interposed between the element and the upper surface (or the lower surface)".

[0113] In addition, when an element is described as "connected to another element", "coupled to another element", or "in contact with another element", it should be understood that the element can be "directly connected to another element", "directly coupled to another element", or "directly in contact with another element", or the element can be "connected to another element", "coupled to another element", or "in contact with another element" in such a manner that yet another element is interposed between the element and the other element or via yet another element.

[0114] Unless the context clearly indicates otherwise, expressions in the singular form used herein include the plural form. Terms such as "consisting of" or "including" used herein should not be construed as necessarily including all elements in the elements described in the specification or all steps in the steps, and should be construed as not including some elements in the elements or some steps in the steps, or including additional elements or steps.

[0115] In addition, unless the context clearly indicates otherwise, expressions in the singular form used herein include the plural form. Terms such as "consisting of" or "including" used herein should not be construed as necessarily including all elements in the elements described in the specification or all steps in the steps, and should be construed as not including some elements in the elements or some steps in the steps, or including additional elements or steps.

[0116] Throughout the specification, unless otherwise specifically stated, "A and / or B" means A, B, or A and B, and unless otherwise specifically stated, "C to D" means from equal to or higher than C to equal to or lower than D.

[0117] Hereinafter, an example of the structure of a pouch-type battery cell that can be sealed by a sealing device according to the present invention will be described with reference to the accompanying drawings.

[0118] Figure 1 is a perspective view illustrating the structure of a pouch-type battery cell, and Figure 2 is a cross-sectional view illustrating a first sealing portion of the pouch-type battery cell. Referring to Figure 1 and Figure 2 , the pouch-type battery cell 1 may include an electrode assembly 11, an electrode tab 12, an electrode lead 13, and a pouch 14.

[0119] The electrode assembly 11 can be formed by repeatedly stacking a plurality of electrodes with separators interposed therebetween. The electrodes can include a positive electrode and a negative electrode. That is, the electrode assembly 11 can be formed by repeatedly and alternately stacking a plurality of positive electrodes and a plurality of negative electrodes, with a separator interposed between the positive electrode and the negative electrode.

[0120] The electrode tabs 12 can extend from each electrode of the electrode assembly 11. A plurality of electrode tabs 12 of the same polarity extending from a plurality of electrodes can be stacked together to form a single tab. That is, a plurality of positive electrodes can be connected in parallel to jointly form the electrode tab 12, and a plurality of negative electrodes can be connected in parallel to jointly form another electrode tab 12.

[0121] The pouch 14 can include a metal sheet material. The pouch 14 can surround and accommodate the electrode assembly 11. The pouch 14 can be sealed at a first sealing portion 143a and a second sealing portion 143b. The first sealing portion 143a is provided at two longitudinal ends of the pouch and extends along the width direction of the pouch, and the second sealing portion 143b is provided at one widthwise end of the pouch and extends along the length direction of the pouch. Each of the sealing portions can be formed by welding. The sealing method of the pouch 14 will be described later.

[0122] The electrode lead 13 can be connected to the electrode tab 12. The connection can be established by welding. The welding can be achieved by various methods such as ultrasonic welding, resistance welding, and laser welding. The electrode lead 13 can extend along the length direction of the pouch and protrude from the pouch 14 through the first sealing portion 143a.

[0123] Here, a lead film 131 can be provided at the electrode lead 13. The lead film 131 can be provided at a position corresponding to the first sealing portion 143a and is interposed between two layers of the pouch 14. The lead film 131 can include a fusible material such as a thermoplastic synthetic resin. The lead film 131 can include a material having electrical insulation properties. For example, the lead film 131 can include a polypropylene material.

[0124] Figure 3 is an enlarged cross-sectional view showing the structure of the insulating layer of the pouch. Refer to Figure 3 The pouch 14 can include a metal layer 141 and an insulating layer 142. The insulating layer 142 can include an inner insulating layer 142a and an outer insulating layer 142b.

[0125] The metal layer 141 can include a metal sheet material. The metal layer 141 can include a conductive metal material. For example, the metal layer 141 can include aluminum.

[0126] The insulating layer 142 can include a material having electrical insulation properties. For example, the insulating layer can include a synthetic resin having electrical insulation properties.

[0127] The inner insulating layer 142a can be coated on the inner surface of the metal layer 141. The inner insulating layer 142a can include a fusible material, such as a thermoplastic synthetic resin. For example, the inner insulating layer 142a can include a polypropylene material. The inner insulating layer 142a can insulate the electrode assembly 11, the electrode tab 12, and the electrode lead 13 from the metal layer 141.

[0128] The outer insulating layer 142b can be coated on the outer surface of the metal layer 141. The outer insulating layer 142b can include the same material as the inner insulating layer 142a. The outer insulating layer 142b can insulate the metal layer 141 from the outside of the bag 14. For example, when a plurality of battery cells 1 are stacked to form a battery module, the outer insulating layer 142b can insulate the metal layers of the bags of the plurality of battery cells 1 from each other.

[0129] The first sealing portion 143a can be formed by a fusion seal. The fusion seal can be achieved by subjecting the inner insulating layer 142a and the lead film 131 to fusion. Specifically, the seal between the two layers of the bag 14 is achieved by subjecting the inner insulating layer 142a to fusion, and the seal between the bag 14 and the electrode lead 13 is achieved by subjecting the lead film 131 to fusion. Thus, the bag 14 can be sealed with two mutually insulated metal layers 141, and the electrode lead 13 is also insulated from the metal layer of the bag 14.

[0130] When both the lead film 131 and the inner insulating layer 142a are made of polypropylene, since polypropylene has a melting point of about 160 degrees Celsius, a sealing device capable of heating the portion to be sealed to more than 160 degrees Celsius and applying pressure to this portion is required to form the first sealing portion 143a.

[0131] The second sealing portion 143b can be formed by a fusion seal. The fusion seal can be achieved by subjecting the inner insulating layer 142a to fusion. Thus, the bag 14 can be sealed with mutually insulated metal layers 141.

[0132] When the inner insulating layer 142a is made of polypropylene, since polypropylene has a melting point of about 160 degrees Celsius, a sealing device capable of heating the portion to be sealed to more than 160 degrees Celsius and applying pressure to this portion is required to form the second sealing portion 143b.

[0133] Hereinafter, the structure and problems of a conventional sealing device will be described. Hereinafter, although the first sealing portion 143a is illustrated, the structure and problems of the second sealing portion 143b are the same.

[0134] Figure 4 and Figure 5 illustrates the structure and arrangement of a conventional sealing device. Refer to Figure 4 andFigure 5 The conventional sealing device 2 includes a sealing tool 21 , a sealing block 22 , a heating rod 23 and an insulating frame 24 .

[0135] The sealing tool 21 includes a metal material and extends in the width direction of the bag. A groove 211 is provided at the center in the width direction of the sealing tool 21, and the groove 211 has a width and a depth corresponding to the width and thickness of the electrode lead 13.

[0136] The sealing block 22 is connected to the sealing tool 21. The sealing block 22 is made of a metal material and extends in the width direction of the bag. A first hole 221 extending in the width direction of the bag is provided in the sealing block 22.

[0137] The insulating frame 24 has one open end in the height direction and accommodates the sealing block 22. The insulating frame 24 includes an insulating material. Second holes 241 corresponding to the first holes 221 are respectively provided at both ends in the width direction of the insulating frame 24.

[0138] The heating rod 23 is inserted into the first hole 221 through the second hole 241. The heating rod 23 may be heated, and then, the sealing block 22 and the sealing tool 21 are heated.

[0139] A pair of sealing devices 2 are arranged along the height direction of the bag in such a manner that the sealing tools 21 face each other. When sealing the bag 14, the pair of sealing devices 2 are arranged at both height direction sides of the portion to be sealed of the bag to form a first sealed portion 143a.

[0140] Figure 6 It's a picture. Figure 4 Cross-sectional view of a sealing device sealing a bag. Figure 6 When the heated sealing tool 21 heats the portion to be sealed and applies pressure to the portion to form a first sealing portion 143 a , the lead film 131 and the inner insulating layer 142 a are melted, re-solidified, and welded to seal the bag 14 and the electrode lead 13 .

[0141] Here, the heat conducted from the sealing tool 21 to the bag 14 may be conducted along the metal layer 141 to the bag 14 except the first sealing portion 143a. Heat is also conducted from the sealing tool 21 to the bag 14 by radiation and convection. Due to such conductive heat, radiant heat, and convection heat, the bag 14 except the first sealing portion 143a is also heated, so that the inner insulating layer 142a and / or the outer insulating layer 142b may be melted and damaged. When the insulating layer 142 is damaged, the performance of the battery cell 1 may be reduced, and there is a risk that a short circuit may occur, resulting in a fire.

[0142] In addition, the heat conducted from the sealing tool 21 to parts other than the first sealing part 143a is not recovered and is lost, thereby reducing the energy efficiency of the sealing device 2.

[0143] Therefore, the present invention provides a structure of a sealing device, which includes a pair of sealing tool assemblies, and the pair of sealing tool assemblies includes an exothermic sealing tool, an endothermic sealing tool, and an endothermic / exothermic device.

[0144] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0145] [First Embodiment]

[0146] The sealing device according to the first embodiment of the present invention can be used to form a first sealing part.

[0147] Figure 7 And Figure 8 are an exploded perspective view and a perspective view respectively illustrating the structure of the sealing tool assembly according to the first embodiment of the present invention. Refer to Figure 7 and Figure 8 , the sealing device according to the present invention may include a pair of sealing tool assemblies, and each of the pair of sealing tool assemblies includes an exothermic sealing tool 31, an endothermic sealing tool 32, and an endothermic / exothermic device 33.

[0148] The exothermic sealing tool 31 may include a metal material and extend along the width direction of the bag. The exothermic sealing tool 31 may be provided with a first groove 311 corresponding to the shape of the electrode lead 13. The first groove 311 may be formed by recessing a part of the center in the width direction of one height direction end of the exothermic sealing tool toward the other height direction end. The length of the first groove 311 in the width direction of the bag may be equal to the width of the electrode lead 13, and the depth of the first groove 311 may be equal to the thickness of the electrode lead 13 or half of it.

[0149] The endothermic sealing tool 32 may include a metal material and extend along the width direction of the bag. The endothermic sealing tool 32 may be provided with a second groove 321 corresponding to the shape of the electrode lead 13. The second groove 321 may be formed by recessing a part of the center in the width direction of one height direction end of the endothermic sealing tool toward the other height direction end. The length of the second groove 321 in the width direction of the bag may be equal to the width of the electrode lead 13, and the depth of the second groove 321 may be equal to the thickness of the electrode lead 13 or half of it.

[0150] The endothermic sealing tool 32 can be juxtaposed with the exothermic sealing tool 31 along the length of the bag. Here, one endothermic sealing tool 32 can be included in each sealing tool assembly, or two endothermic sealing tools 32 can be included in each sealing tool assembly. When one endothermic sealing tool 32 is provided in each sealing tool assembly, the endothermic sealing tool 32 can be set more inward in the length direction than the exothermic sealing tool 31. When two endothermic sealing tools 32 are provided in each sealing tool assembly, the endothermic sealing tools 32 can be provided on both lengthwise sides of the exothermic sealing tool 31.

[0151] The endothermic / exothermic device 33 can be interposed between the exothermic sealing tool 31 and the endothermic sealing tool 32. The endothermic / exothermic device 33 can radiate heat through its first surface and absorb heat through its second surface opposite to the first surface. The endothermic / exothermic device 33 can be arranged such that its first surface is in contact with the exothermic sealing tool 31 and its second surface is in contact with the endothermic sealing tool 32. Thus, the endothermic / exothermic device 33 can heat the exothermic sealing tool 31 and cool the endothermic sealing tool 32. Preferably, when a voltage is applied to the endothermic / exothermic device 33, the first surface of the endothermic / exothermic device 33 radiates heat, and the second surface of the endothermic / exothermic device 33 absorbs heat, thereby heating the exothermic sealing tool 31 and cooling the endothermic sealing tool 32.

[0152] A plurality of endothermic / exothermic devices 33 can be arranged to be in contact with the wider surfaces of the exothermic sealing tool 31 and the endothermic sealing tool 32. Specifically, a plurality of endothermic / exothermic devices 33 arranged in a grid form can be arranged to be in contact with the surfaces of the exothermic sealing tool 31 and the endothermic sealing tool 32 parallel to the length direction of the bag. Since the plurality of endothermic / exothermic devices 33 are in contact with the exothermic sealing tool 31 and the endothermic sealing tool 32 at a plurality of points, heating and cooling can occur quickly and at a high level, and it is beneficial to maintain the heating state and the cooling state.

[0153] The sealing tool assembly can include an insulating plate 34. The insulating plate 34 can be arranged in the space between the exothermic sealing tool 31 and the endothermic sealing tool 32 where the endothermic / exothermic device 33 is not provided. The insulating plate 34 can include an insulating material. The insulating plate 34 can be interposed between the exothermic sealing tool 31 and the endothermic sealing tool 32, and the insulating plate 34 can be provided with through holes for mounting the endothermic / exothermic device 33 therein. By providing the insulating plate 34, heat conduction between the exothermic sealing tool 31 and the endothermic sealing tool 32 only occurs in the area where the endothermic / exothermic device 33 is provided, and heat energy of the exothermic sealing tool 31 is prevented from being conducted to the endothermic sealing tool 32 through other parts.

[0154] Figure 9 and Figure 10Illustrated are the structure of a thermoelectric element and the heating and cooling operations of the thermoelectric element according to a first embodiment of the present invention. Referring to Figure 9 and Figure 10 , the heat absorption / dissipation device 33 may include a thermoelectric element (Peltier element). A thermoelectric element is a semiconductor device that includes multiple pairs of P-type semiconductors and N-type semiconductors that are electrically connected in series and thermally connected in parallel and can maintain a constant temperature difference between a first side portion and a second side portion when a constant DC voltage is applied.

[0155] The thermoelectric element 33 releases the thermal energy absorbed from the heat absorption sealing tool 32 to the heat dissipation sealing tool 31, thereby maintaining a constant temperature difference between the heat dissipation sealing tool 31 and the heat absorption sealing tool 32. When a DC voltage is applied to the thermoelectric element 33 when both the heat dissipation sealing tool 31 and the heat absorption sealing tool 32 are at room temperature, the temperature of the heat dissipation sealing tool 31 can rise above room temperature, and the temperature of the heat absorption sealing tool 32 can drop below room temperature. Here, when the heat absorption sealing tool 32 is provided on both sides of the heat dissipation sealing tool 31, the thermal energy obtained by the heat dissipation sealing tool 31 is twice the thermal energy lost by each heat absorption sealing tool 32.

[0156] Figure 11 Illustrated is a sealing tool assembly accommodated in an insulating frame according to a first embodiment of the present invention. Referring to Figure 11 , the sealing device may include a pair of insulating frames 35 that respectively accommodate a pair of sealing tool assemblies. The insulating frames 35 may be entirely made of an insulating material or may be provided with an insulating layer that covers each side portion, preferably the vertical side portion, from the inside or the outside. Preferably, each of the insulating frames 35 in the insulating frames 35 may have five closed side portions that respectively cover five side portions of each of the sealing tool assemblies in the sealing tool assembly except for a first height direction end portion and a second height direction end portion that respectively face a first sealing portion. Compared with a conventional sealing device in which a sealing tool is fixed to a sealing block and the insulating frame only covers the sealing block, in the sealing device according to the first embodiment, the sealing tool assembly itself is covered, so that heat loss due to radiant heat and convective heat generated along the horizontal direction from the sealing tool assembly can be reduced more effectively, and thus the energy efficiency is excellent.

[0157] Figure 12 Illustrated is the arrangement of a sealing device according to a first embodiment of the present invention. Referring to Figure 12, the sealing device includes a pair of sealing tool assemblies and a pair of insulating frames 35 that respectively accommodate the pair of sealing tool assemblies, and the pair of sealing devices are respectively provided on both sides of the first sealing portion 143a in the height direction of the bag. When the first groove 311 and / or the second groove 321 are provided in the exothermic sealing tool 31 and / or the endothermic sealing tool 32, each of the sealing tool assemblies in the sealing tool assembly can be arranged in such a way that the first groove 311 and / or the second groove 321 face the first sealing portion 143a.

[0158] Figure 13 is a cross-sectional view showing the sealing of a bag by the sealing device according to the first embodiment of the present invention. Refer to Figure 13 , the exothermic sealing tool 31 of the sealing device applies pressure and heat from above and below the portion to be sealed to weld the inner insulating layer 142a and the lead film 131, thereby forming the first sealing portion 143a. Here, the endothermic sealing tool 32 contacts the bag 14 on both longitudinal sides of the portion to be sealed to cool both longitudinal sides of the portion to be sealed, thereby preventing damage to portions of the insulating layer 142 other than the first sealing portion 143a of the insulating layer 142.

[0159] Figure 14 illustrates the movement of heat when the sealing device seals the bag according to the first embodiment of the present invention. Refer to Figure 14 , when a predetermined DC voltage is applied to the thermoelectric element 33, the thermoelectric element 33 absorbs the thermal energy of the endothermic sealing tool 32 and radiates heat to the exothermic sealing tool 31 to keep the temperature difference between the endothermic sealing tool 32 and the exothermic sealing tool 31 constant, thereby heating the exothermic sealing tool 31 to a temperature higher than room temperature and cooling the endothermic sealing tool 32 to a temperature lower than room temperature. Here, since the heat transfer from the exothermic sealing tool 31 to the endothermic sealing tool 32 due to conduction, radiation, and convection is blocked by the insulating plate 34, only one-way heat transfer from the endothermic sealing tool 32 to the exothermic sealing tool 31 occurs. Even when thermal energy is transferred from the exothermic sealing tool 31 to the endothermic sealing tool 32, the thermal energy is transferred back to the exothermic sealing tool 31 through the thermoelectric element 33. In addition, due to the insulating plate 34 and the endothermic sealing tool 32, heat loss due to conduction, radiation, and convection from the exothermic sealing tool 31 to the outside can also be prevented.

[0160] The thermal energy absorbed by the exothermic sealing tool 31 is transferred to the inner insulating layer 142a and the lead film 131 inside the portion to be sealed through the surface of the portion to be sealed in contact with the exothermic sealing tool 31. The remaining thermal energy after melting the inner insulating layer 142a and the lead film 131 is transferred to both longitudinal sides of the first sealing portion 143a through the bag 14, and the endothermic sealing tool 32 can absorb the transferred thermal energy. That is, the endothermic sealing tool 32 absorbs the remaining heat after the exothermic sealing tool 31 melts the lead film 131 and the inner insulating layer 142a to form the first sealing portion 143a, and the absorbed heat is supplied back to the exothermic sealing tool 31 through the thermoelectric element 33. Here, the endothermic sealing tool 32 can not only absorb thermal energy from the bag 14 but also absorb thermal energy from the external air and supply the absorbed thermal energy back to the thermoelectric element 33.

[0161] In summary, the sealing device according to the first embodiment of the present invention can absorb and utilize the remaining energy after forming the first sealing portion 143a, and the insulating plate 34, the endothermic sealing tool 32, and the insulating frame 35 prevent heat loss caused by conduction, radiation, and convection from the exothermic sealing tool 31 to the outside, resulting in high energy efficiency. At the same time, only the desired area can be targeted and sealed, and the adjacent portions can be cooled below room temperature, reducing the risk of damaging the adjacent portions.

[0162] [Second Embodiment]

[0163] The sealing device according to the second embodiment of the present invention can be used to form the second sealing portion 143b. Hereinafter, the parts not separately described in the second embodiment are the same as those in the first embodiment.

[0164] Figure 15 and Figure 16 are an exploded perspective view and a perspective view respectively illustrating the structure of the sealing tool assembly according to the second embodiment of the present invention. Referring to Figure 15 and Figure 16 , the sealing device according to the present invention may include a pair of sealing tool assemblies, and each of the pair of sealing tool assemblies includes an exothermic sealing tool 41, an endothermic sealing tool 42, and an endothermic / exothermic device 43.

[0165] The exothermic sealing tool 41 may include a metallic material and extend along the longitudinal direction of the bag.

[0166] The endothermic sealing tool 42 may include a metallic material and extend along the longitudinal direction of the bag.

[0167] The endothermic sealing tool 42 can be juxtaposed with the exothermic sealing tool 41 along the width direction of the bag. Here, one endothermic sealing tool 42 can be included in each sealing tool assembly, or two endothermic sealing tools 42 can be included in each sealing tool assembly. When one endothermic sealing tool 42 is provided in each sealing tool assembly, the endothermic sealing tool 42 can be set more inward in the width direction than the exothermic sealing tool 41. When two endothermic sealing tools 42 are provided in each sealing tool assembly, the endothermic sealing tools 42 can be provided on both width direction sides of the exothermic sealing tool.

[0168] The endothermic / exothermic device 43 can be interposed between the exothermic sealing tool 41 and the endothermic sealing tool 42. The endothermic / exothermic device 43 can radiate heat through its first surface and absorb heat through its second surface opposite to the first surface. The endothermic / exothermic device 43 can be arranged such that its first surface is in contact with the exothermic sealing tool 41 and its second surface is in contact with the endothermic sealing tool 42. Therefore, the endothermic / exothermic device 43 can heat the exothermic sealing tool 41 and cool the endothermic sealing tool 42. Preferably, when a voltage is applied to the endothermic / exothermic device 43, the first surface of the endothermic / exothermic device 43 radiates heat, and the second surface of the endothermic / exothermic device 43 absorbs heat, thereby heating the exothermic sealing tool 41 and cooling the endothermic sealing tool 42. The endothermic / exothermic device 43 can include a thermoelectric element (Peltier element).

[0169] A plurality of endothermic / exothermic devices 43 can be arranged to be in contact with the wider surfaces of the exothermic sealing tool 41 and the endothermic sealing tool 42. Specifically, a plurality of endothermic / exothermic devices 43 arranged in a grid form can be arranged to be in contact with the surfaces of the exothermic sealing tool 41 and the endothermic sealing tool 42 parallel to the width direction of the bag. Since the plurality of endothermic / exothermic devices 43 are in contact with the exothermic sealing tool 41 and the endothermic sealing tool 42 at multiple points, heating and cooling can occur quickly and at a high level, and it is beneficial to maintain the heating state and the cooling state.

[0170] The sealing tool assembly can include an insulating plate 44. The insulating plate 44 can be arranged in the space between the exothermic sealing tool 41 and the endothermic sealing tool 42 where the endothermic / exothermic device 43 is not provided. The insulating plate 44 can include an insulating material. The insulating plate 44 can be interposed between the exothermic sealing tool 41 and the endothermic sealing tool 42, and the insulating plate 44 can be provided with through holes for mounting the endothermic / exothermic device 43 therein. By providing the insulating plate 44, heat conduction between the exothermic sealing tool 41 and the endothermic sealing tool 42 only occurs in the area where the endothermic / exothermic device 43 is provided, and heat energy of the exothermic sealing tool 41 is prevented from being conducted to the endothermic sealing tool 42 through other parts.

[0171] Figure 17Illustrated is a sealing tool assembly accommodated in an insulating frame according to a second embodiment of the present invention. Referring to Figure 17 , the sealing device may include a pair of insulating frames 45 that respectively accommodate a pair of sealing tool assemblies. The insulating frames 45 may be entirely made of an insulating material or may be provided with an insulating layer that covers each side, preferably the vertical sides, from the inside or the outside. Preferably, each of the insulating frames 45 in the pair of insulating frames may have five closed sides that respectively cover five sides of each of the sealing tool assemblies in the pair of sealing tool assemblies, excluding the first height-direction end and the second height-direction end that respectively face the first sealing portion. Compared with a conventional sealing device in which the sealing tool is fixed to the sealing block and the insulating frame only covers the sealing block, in the sealing device according to the second embodiment, the sealing tool assembly itself is covered, so that heat loss due to radiant heat and convective heat generated along the horizontal direction from the sealing tool assembly can be more effectively reduced, and thus the energy efficiency is excellent.

[0172] Figure 18 Illustrated is the arrangement of a sealing device according to a second embodiment of the present invention. Referring to Figure 18 , the sealing device includes a pair of sealing tool assemblies and a pair of insulating frames 45 that respectively accommodate the pair of sealing tool assemblies, and the pair of sealing devices are respectively provided on both sides of a second sealing portion 143b in the height direction of the bag.

[0173] Figure 19 is a cross-sectional view illustrating the sealing of a bag by a sealing device according to a second embodiment of the present invention. Referring to Figure 19 , the exothermic sealing tool 41 of the sealing device applies pressure and heat from above and below the portion to be sealed to fuse the inner insulating layer 142a, thereby forming the second sealing portion 143b. Here, the endothermic sealing tool 42 contacts the bag 14 on both width-direction sides of the second sealing portion 143b to cool both width-direction sides of the portion to be sealed, thereby preventing damage to portions of the insulating layer 142 other than the portion of the insulating layer 142 provided at the portion to be sealed.

[0174] It should be understood that the described embodiments are illustrative in all aspects and not restrictive, and the scope of the present invention will be indicated by the following claims rather than the described detailed description. And the meaning and scope of the claims to be described later, as well as all variations and modifications derived from equivalent concepts, should be construed as being included within the scope of the present invention.

[0175] Although the present invention has been described with reference to the illustrative drawings, it is to be understood that the present invention is not limited to the embodiments and the drawings disclosed in this specification, and those skilled in the art will understand that various modifications can be made without departing from the scope and concept of the present invention. In addition, although the operational effects of the configuration according to the present invention are not explicitly described when describing the embodiments of the present invention, it should be understood that predictable effects will also be recognized by this configuration.

Claims

1. A sealing device for forming, by welding, a first sealing portion along a width direction at two longitudinal ends of a bag of a pouch-type battery cell, the sealing device comprising: A pair of sealing tool assemblies respectively disposed above and below the first sealing portion, each sealing tool assembly of the pair of sealing tool assemblies comprising: an exothermic sealing tool extending along the width direction; an endothermic sealing tool extending along the width direction and juxtaposed with the exothermic sealing tool along a length direction; and an endothermic / exothermic device interposed between the exothermic sealing tool and the endothermic sealing tool, wherein the endothermic / exothermic device simultaneously radiates heat to the exothermic sealing tool and absorbs heat from the endothermic sealing tool, respectively.

2. The sealing device according to claim 1, wherein, When an electric current is applied, the endothermic / exothermic device radiates heat through a first surface of the endothermic / exothermic device and absorbs heat through a second surface of the endothermic / exothermic device opposite to the first surface, and the endothermic / exothermic device is interposed between the exothermic sealing tool and the endothermic sealing tool, wherein the first surface contacts the exothermic sealing tool and the second surface contacts the endothermic sealing tool.

3. The sealing device according to claim 2, wherein, The endothermic / exothermic device includes a Peltier element which, when an electric current is applied, radiates heat through the first surface and absorbs heat through the second surface.

4. The sealing device according to claim 1, wherein, The pouch-type battery cell includes electrode leads extending from inside the bag and protruding through the first sealing portion, and the exothermic sealing tool is provided with a first groove corresponding to the shape of the electrode leads.

5. The sealing device according to claim 4, wherein, The endothermic sealing tool is provided with a second groove corresponding to the shape of the electrode leads.

6. The sealing device according to claim 1, wherein, Each sealing tool assembly is provided with one endothermic sealing tool, and the one endothermic sealing tool is disposed more inward in the length direction than the exothermic sealing tool.

7. The sealing device according to claim 1, wherein Each sealing tool assembly is provided with two endothermic sealing tools, and the two endothermic sealing tools are disposed on two longitudinal sides of the exothermic sealing tool.

8. The sealing device according to claim 1, wherein, Each sealing tool assembly of the pair of sealing tool assemblies further includes an insulating plate disposed in a space between the exothermic sealing tool and the endothermic sealing tool where the endothermic / exothermic device is not provided.

9. The sealing device according to claim 1, further comprising a pair of insulating frames respectively accommodating the pair of sealing tool assemblies.

10. The sealing device according to claim 9, wherein, Each insulating frame of the insulating frames has five closed side portions respectively covering five sides of each sealing tool assembly of the sealing tool assemblies except for a first height-direction end portion and a second height-direction end portion thereof respectively facing the first sealing portion.

11. A sealing device for forming, by welding, a second sealing portion along a length direction at one width direction end of a bag of a pouch-type battery cell, the sealing device comprising: A pair of sealing tool assemblies are respectively arranged above and below the second sealing part. Each sealing tool assembly in the pair of sealing tool assemblies includes: an exothermic sealing tool that extends along the length direction; an endothermic sealing tool that extends along the length direction and is juxtaposed with the exothermic sealing tool along the width direction; and an endothermic / exothermic device that is inserted between the exothermic sealing tool and the endothermic sealing tool. Wherein, the endothermic / exothermic device simultaneously radiates heat to the exothermic sealing tool and absorbs heat from the endothermic sealing tool respectively.

12. The sealing device according to claim 11, wherein, When an electric current is applied, the endothermic / exothermic device radiates heat through the first surface of the endothermic / exothermic device and absorbs heat through the second surface of the endothermic / exothermic device opposite to the first surface, and the endothermic / exothermic device is inserted between the exothermic sealing tool and the endothermic sealing tool, wherein the first side portion contacts the exothermic sealing tool and the second side portion contacts the endothermic sealing tool.

13. The sealing device according to claim 12, wherein, The endothermic / exothermic device includes a Peltier element. When an electric current is applied, the Peltier element radiates heat through the first side portion and absorbs heat through the second side portion.

14. The sealing device according to claim 11, wherein, Each sealing tool assembly is provided with one endothermic sealing tool, and the one endothermic sealing tool is arranged more inward in the width direction than the exothermic sealing tool.

15. The sealing device according to claim 11, wherein, Each sealing tool assembly is provided with two endothermic sealing tools, and the two endothermic sealing tools are arranged on two width direction sides of the exothermic sealing tool.

16. The sealing device according to claim 11, wherein, Each sealing tool assembly in the pair of sealing tool assemblies further includes an insulating plate, and the insulating plate is arranged in the space between the exothermic sealing tool and the endothermic sealing tool where the endothermic / exothermic device is not provided.

17. The sealing device according to claim 11 further includes a pair of insulating frames that respectively accommodate the pair of sealing tool assemblies.

18. The sealing device according to claim 17, wherein, Each insulating frame in the pair of insulating frames has five closed side portions that respectively cover five side portions of each sealing tool assembly in the sealing tool assemblies except for the first height direction end portion and the second height direction end portion that respectively face the second sealing part.

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