Sealing Device

Abstract

The present invention relates to a sealing device, and more particularly to a sealing device capable of maintaining a constant temperature of a sealing surface of the sealing device even when a suitable solvent is continuously heated using a phase change of a material, thereby manufacturing a pouch sealing part of a pouch secondary battery product with uniform and excellent quality. The sealing device according to the present invention includes a sealing body having a sealing surface on one side for sealing an object to be sealed, a solvent contacting the other side of the sealing body to supply heat to the sealing body, and a heat source for heating the solvent such that at least a portion of the solvent changes phase to gas.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0093793 dated July 16, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a sealing device, and more particularly to a sealing device capable of maintaining a constant temperature of a sealing surface of the sealing device even when a suitable solvent is continuously heated using a phase change of a material, thereby manufacturing a pouch sealing part of a pouch secondary battery product with uniform and excellent quality. [Background technology]

[0003] Secondary batteries capable of repeated charging and discharging may be classified into cylindrical secondary batteries, prismatic secondary batteries, pouch-type secondary batteries, etc., depending on their structure and manufacturing method. Among them, the pouch-type secondary battery is manufactured by accommodating an electrode assembly in a pouch sheet and then sealing the pouch sheet. It has a simple structure and a large capacity per unit volume compared to other types of secondary batteries, and is widely used in automobile batteries, energy storage devices, etc.

[0004] More specifically, a pouch-type secondary battery is generally manufactured by forming a cup in a pouch sheet, accommodating an electrode assembly in the cup, folding the pouch sheet so that a region of the pouch sheet covers the electrode assembly, and then forming a sealing portion that seals the periphery of the electrode assembly.

[0005] FIG. 1 is a cross-sectional view illustrating a conventional sealing device.

[0006] Referring to Fig. 1, a conventional sealing device 1 has a heat source 30, such as a heat line, built into a sealing tool 10 that performs sealing. When the sealing tool 10 is heated by the heat source 30, the temperature of the sealing tool 10 increases, and the temperature of the sealing surface 11 that directly contacts the pouch to perform sealing increases accordingly. Then, sealing is performed after the temperature of the sealing surface 11 is increased to a temperature suitable for sealing.

[0007] FIG. 2 is a diagram illustrating a temperature change on the sealing surface in the sealing device of FIG.

[0008] 2, in the conventional sealing device 1, the temperature of the sealing surface 11 was not always kept constant at the sealing target temperature. When the temperature of the sealing surface 11 rose above the sealing target temperature, the heat source 30 was turned off to lower the temperature of the sealing surface 11, and when the temperature of the sealing surface 11 fell below the sealing target temperature, the heat source 30 was turned on to heat the sealing surface 11 to raise the temperature of the sealing surface 11. Therefore, the temperature of the sealing surface 11 could not always be kept constant, but was controlled to draw a fluctuating form as shown in FIG. 2.

[0009] If the pouch sealing is performed at such an inconsistent temperature, the quality of the sealed pouch will not be uniform, which may result in defects such as leakage or breakage. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been devised to solve the above problems, and an object of the present invention is to provide a sealing device that can maintain a constant temperature of the sealing surface of the sealing device even when an appropriate solvent is continuously heated using a phase change of a material, thereby manufacturing a pouch sealing part of a pouch secondary battery product with uniform and excellent quality. [Means for solving the problem]

[0011] The sealing device according to the present invention includes a sealing body having a sealing surface on one side for sealing an object to be sealed, a solvent contacting the other side of the sealing body to supply heat to the sealing body, and a heat source for heating the solvent such that at least a portion of the solvent changes phase to gas.

[0012] The sealing body can seal the object while at least a portion of the solvent undergoes a phase change to gas.

[0013] The sealing body may further include a housing having a structure coupled thereto and configured to contain a solvent.

[0014] The housing may include a sidewall portion extending upward from a frame portion of the sealing body, and the solvent may be contained in a liquid state in an inner space having a concave shape formed by the other surface of the sealing body and the sidewall portion.

[0015] The heat source may be at least partially immersed in the solvent in a liquid state but spaced a predetermined distance from the sealing body.

[0016] The apparatus may further include a condenser for condensing the solvent that has undergone a phase change to a gas into a liquid.

[0017] The condenser can be located above the heat source.

[0018] The solvent can be vaporized by a heat source and move upward, and can be liquefied by a condenser and move downward.

[0019] The condenser may be located within the housing.

[0020] Between the heat source and the condenser there may be an insulating gap or an insulating plate.

[0021] The solvent may be a substance with a boiling point between 180 and 200 degrees Celsius.

[0022] The solvent may be any one selected from the group consisting of ethylene glycol, propylene glycol, and dimethyl sulfoxide. Effect of the Invention

[0023] The sealing device according to the present invention includes a sealing body having a sealing surface on one side for sealing a sealing target, a solvent contacting the other side of the sealing body to supply heat to the sealing body, and a heat source for heating the solvent so that at least a part of the solvent changes phase to gas, so that the temperature of the sealing surface of the sealing device can be kept constant even when the appropriate solvent is continuously heated using the phase change of the material, and as a result, the pouch sealing part of the pouch secondary battery product can be manufactured with uniform and excellent quality. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a cross-sectional view illustrating a conventional sealing device. [Diagram 2] 2 is a diagram illustrating a temperature change of a sealing surface in the sealing device of FIG. 1. [Diagram 3] FIG. 1 is a cross-sectional view illustrating a sealing device according to a first embodiment of the present invention. [Figure 4] 4 is a diagram illustrating a temperature change of a sealing surface in the sealing device of FIG. 3. [Diagram 5] FIG. 4 is a cross-sectional view illustrating a sealing device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

[0026] This invention may, however, be embodied in many different forms and should not be construed as limited to or by the embodiments set forth herein.

[0027] In order to clearly explain the present invention, detailed descriptions of parts that are not relevant to the explanation or related prior art that may unnecessarily obscure the gist of the present invention will be omitted, and when adding reference symbols to components in each drawing in this specification, the same or similar reference symbols will be used for the same or similar components throughout the specification.

[0028] Furthermore, the terms and words used in the description and claims of the present invention should not be interpreted in a limited manner to their ordinary or dictionary meanings, but should be interpreted in a manner consistent with the technical ideas of the present invention, based on the principle that an inventor can appropriately define the concepts of terms in order to best describe his or her invention.

[0029] (Embodiment 1) Fig. 3 is a cross-sectional view illustrating a sealing device according to embodiment 1 of the present invention, and Fig. 4 is a view illustrating a temperature change of a sealing surface in the sealing device of Fig. 3.

[0030] Referring to FIG. 3, a sealing device 100 according to the first embodiment of the present invention may include a sealing body 110, a solvent 120, and a heat source .

[0031] The sealing body 110 may have a sealing surface 111 on one side for sealing the object to be sealed. The object to be sealed may be a pouch for a secondary battery used as a case for the secondary battery. Among secondary batteries, a pouch-type battery may be manufactured by forming a pouch made of aluminum coated with resin to create an internal space, housing an electrode assembly in the internal space, and sealing a peripheral portion of the pouch located around the housed electrode assembly. The sealing device 100 according to the first embodiment of the present invention may be used to seal the pouch in a sealing process during a manufacturing process of such a pouch-type secondary battery.

[0032] The solvent 120 may be configured to contact the other surface 112 of the sealing body and supply heat to the sealing body 110. The solvent 120 may be in a liquid form and provided to contact the other surface 112 of the sealing body. The solvent 120 may be heated by receiving heat from a heat source 130 described below, and when the temperature of the solvent 120 increases, the solvent 120 may supply heat to the sealing body 110.

[0033] The heat source 130 may be configured to heat the solvent 120. In particular, the heat source 130 may be configured to heat the solvent 120 such that at least a part of the solvent 120 changes phase from liquid to gas. In addition, the sealing device 100 according to the first embodiment of the present invention may allow the sealing body 110 to seal the sealing target through the sealing surface 111 while at least a part of the solvent 120 changes phase to gas.

[0034] In this manner, the sealing device 100 according to the first embodiment of the present invention uses a phase change of a material, so that the temperature of the sealing surface 111 of the sealing device 100 can be kept constant even if the appropriate solvent is continuously heated. As a result, the pouch sealing can be performed at a constant temperature. As a result, the pouch sealing part of the pouch type secondary battery product can be manufactured with uniform and excellent quality.

[0035] 2, it can be seen that the temperature of the sealing surface 111 is maintained constant in the sealing device 100 according to embodiment 1. In particular, the temperature may be maintained constant in accordance with a sealing target temperature, and in this case, uniform and excellent sealing quality may be realized.

[0036] The sealing target temperature may be a value between 180 degrees Celsius and 200 degrees Celsius. Therefore, the solvent 120 may be a substance having a boiling point between 180 degrees Celsius and 200 degrees Celsius. In one embodiment, the solvent 120 may be any one selected from ethylene glycol, propylene glycol, and dimethyl sulfoxide. The boiling point of ethylene glycol may be about 198 degrees Celsius. The boiling point of propylene glycol may be about 188.2 degrees Celsius. The boiling point of dimethyl sulfoxide may be about 189 degrees Celsius.

[0037] In this manner, the sealing device 100 according to the first embodiment of the present invention can perform sealing at a constant temperature by utilizing the fact that when a material undergoes a phase change, energy flows in and out but there is no change in temperature.

[0038] Also, the sealing device 100 according to the first embodiment of the present invention may further include a housing 140 to accommodate the solvent 120. The housing 140 may have a structure connected to the sealing body 110 and may be configured to accommodate the solvent 120. Since the solvent 120 is positioned to contact the other surface 112 of the sealing body, the housing 140 may be configured to extend to the other surface 112 of the sealing body.

[0039] Specifically, the housing 140 may include a sidewall 141 extending upward from a frame of the sealing body 110. When such a sidewall 141 is formed, a space may be provided by the other surface 112 of the sealing body and the sidewall 141. At this time, the solvent 120 may be in a liquid state and may be contained in the concave-shaped internal space formed by the other surface 112 of the sealing body and the sidewall 141. Due to this structure, even if the sealing body 110 moves around for sealing, the solvent 120 may always be in contact with the other surface 112 of the sealing body.

[0040] The heat source 130 may be positioned such that at least a portion of it is immersed in the liquid solvent 120 to heat the solvent 120. The heat source 130 may be spaced a predetermined distance from the sealing body 110. If the heat source 130 comes into contact with the sealing body 110, it may rapidly affect the temperature of the sealing body 110, particularly the sealing surface 111. Therefore, the heat source 130 may be positioned so as not to come into contact with the sealing body 110.

[0041] The sealing apparatus 100 according to the first embodiment of the present invention may further include a condenser 150 for condensing the solvent 120, which has changed from a gas phase, into a liquid. The condenser 150 may be located above the heat source 130. The condenser 150 may be located within the housing 140. When the condenser 150 is located within the housing 140, the travel distance of the solvent 120 may be minimized, thereby improving efficiency.

[0042] The principle of operation of the solvent 120 from the sealing device 100 according to the first embodiment of the present invention will be described as follows.

[0043] First, the solvent 120 begins to evaporate when it reaches its boiling point by being heated by the heat source 130. During the process in which the solvent 120 evaporates, the temperature of the solvent 120 is maintained constant, and during that time, the temperature of the sealing body 110 may also be maintained constant.

[0044] 2, the solvent 120 that is heated and vaporized by the heat source 130 can move upward (see arrow No. 1 in FIG. 2). The solvent 120 that moves upward can encounter the condenser 150. When the solvent 120 encounters the condenser 150, it can be condensed (see arrow No. 2 in FIG. 2). That is, the solvent can change phase from gas to liquid.

[0045] After being liquefied by the condenser 150, the solvent 120 may move downward again toward the sealing body 110 (see the third arrow in FIG. 2), and may be heated again by the heat source 130. The solvent 120 heated in this manner may be vaporized again, and may be continuously circulated in this cycle.

[0046] When the cycle is repeated in this manner, the heat source 130 continuously supplies heat, but the temperature of the solvent 120 and the temperature of the sealing surface 111 are continuously maintained constant to perform the sealing operation.

[0047] (Embodiment 2) FIG. 5 is a cross-sectional view illustrating a sealing device according to a second embodiment of the present invention.

[0048] The second embodiment of the present invention is different from the sealing device according to the first embodiment of the present invention in that a heat insulating part 260 is further added.

[0049] The contents common to the first embodiment will be omitted as much as possible, and the differences will be mainly described in the second embodiment. In other words, when the contents not described in the second embodiment are necessary, it is obvious that the contents of the first embodiment can be used to supplement the contents.

[0050] 5, the sealing device 200 according to the second embodiment of the present invention may include a heat insulating part 260 between the heat source 130 and the condenser 150. The heat source 130 and the condenser 150 are located in one housing 140, and since the heat source 130 and the condenser 150 may be maintained at different temperatures, it is necessary that no heat exchange occurs between the two in consideration of energy efficiency. Therefore, a heat insulating part 260 that blocks such heat exchange may be provided between the heat source 130 and the condenser 150.

[0051] Here, the heat insulating portion 260 may be specifically a heat insulating gap or a heat insulating plate, or may be a heat insulating coating or a heat insulating material layer.

[0052] The insulating gap may be a space gap between the heat source 130 and the condenser 150 for thermal insulation. This gap may be a space gap created when the heat source 130 and the condenser 150 are spaced apart from each other. The insulating gap may be filled with a gas having insulating properties, or may be evacuated.

[0053] The heat insulating plate or heat insulating material layer may be formed by forming a material composed of heat insulating components into a layer and disposing it between the heat source 130 and the condenser 150. This may form a physical barrier layer. In particular, when the heat insulating part 260 is formed of a heat insulating plate having a hard property, it may also function as a support part for supporting the weight of the condenser 150.

[0054] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited thereto, and various implementations of the present invention may be made by a person having ordinary skill in the art to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the claims described below. [Explanation of symbols]

[0055] 100, 200: Sealing device 110:Ceiling body 111: Sealing surface 112: Other side of sealing body 120: Solvent 130:Heat source 140: Housing 141: Side wall 150: Condenser 260: Insulation section

Claims

1. A sealing body having a sealing surface on one side for sealing an object to be sealed; a solvent contacting the other surface of the sealing body to supply heat to the sealing body; and a heat source for heating the solvent such that at least a portion of the solvent undergoes a phase change to a gas; The sealing body seals the sealing target while at least a portion of the solvent changes phase to gas; a housing having a structure connected to the sealing body and configured to accommodate the solvent; The housing includes a side wall portion extending upward from a frame portion of the sealing body, The solvent is poured in a liquid state into an inner space having a concave shape formed by the other surface of the sealing body and the side wall portion, The heat source is at least partially contained in the solvent in a liquid state, The sealing body is spaced apart from the sealing member by a predetermined distance. Sealing device.

2. A sealing body having a sealing surface on one side for sealing an object to be sealed; a solvent contacting the other surface of the sealing body to supply heat to the sealing body; and a heat source for heating the solvent such that at least a portion of the solvent undergoes a phase change to a gas; The sealing body seals the sealing target while at least a portion of the solvent changes phase to gas; a housing having a structure connected to the sealing body and configured to accommodate the solvent; The method further includes a condenser for condensing the solvent that has changed into a gas phase into a liquid. Sealing device.

3. The condenser is located above the heat source.

3. The sealing device according to claim 2 , characterized in that

4. The solvent is The liquid is vaporized by the heat source and moves upward, The liquid is liquefied by the condenser and moves downward.

4. The sealing device according to claim 3, characterized in that

5. The condenser is located within the housing.

5. The sealing device according to claim 4, characterized in that

6. There is a thermal insulator between the heat source and the condenser.

4. The sealing device according to claim 3, characterized in that

7. The solvent is a substance with a boiling point between 180 and 200 degrees Celsius.

3. A sealing device according to claim 1 or 2, characterized in that it is

8. The solvent is any one selected from the group consisting of ethylene glycol, propylene glycol, and dimethyl sulfoxide.

8. The sealing device of claim 7.

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