Electrode assembly wrapping device, electrode assembly wrapping method and electrode assembly manufactured by electrode assembly wrapping device and electrode assembly wrapping method

Abstract

In one example, a disclosed electrode assembly wrapping apparatus includes: a lower stage having a plurality of sealing rods on a top surface and movable up and down; the side sealing blocks are arranged on the two side surfaces of the lower table and can move front and back relative to the lower table; and an upper stage which is provided above the lower stage, has a plurality of sealing rods on the lower surface thereof, and is movable up and down with respect to the lower stage.

Description

Technical Field

[0001] The present disclosure relates to an electrode assembly wrapping device and an electrode assembly wrapping method for wrapping a film around the surface of an electrode assembly in which a plurality of battery cells are stacked to fix the battery cells so that they do not separate or misalign, and to an electrode assembly manufactured according to the electrode assembly wrapping device and wrapping method.

[0002] This application claims the priority of Korean Patent Application No. 10-2023-0063887 filed on May 17, 2023 and Korean Patent Application No. 10-2024-0063046 filed on May 14, 2024, all of which are incorporated herein by reference. Background Art

[0003] Unlike primary batteries, secondary batteries are rechargeable and have been widely studied and developed in recent years due to their potential for miniaturization and high capacity. Due to the increasing technological development and demand for mobile devices as well as electric vehicles and energy storage systems that have emerged in response to environmental protection needs, the demand for secondary batteries as an energy source is rapidly increasing.

[0004] Secondary batteries are classified into button-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries according to the shape of the battery case. Among secondary batteries, the electrode assembly installed inside the battery case is a charge-discharge power generation device having a stacked structure including electrodes and a separator.

[0005] Electrode assemblies are generally classified into: wound core type, in which a separator is interposed between a sheet-like positive electrode and a negative electrode coated with an active material and wound; stacked type, in which a plurality of positive electrodes and negative electrodes are sequentially stacked with a separator interposed therebetween; and stacked and folded type, in which stacked unit battery cells are wound in a separator having a relatively long length.

[0006] A stacked electrode assembly is formed by stacking a plurality of battery cells (dual-cell or single-cell with a separator interposed between a positive electrode and a negative electrode) to complete the electrode assembly, and each battery cell should be fixed to maintain precise alignment. To this end, a tape winding process is performed in which multiple rows of tape wrap around the surface of the electrode assembly.

[0007] However, the tape winding process of wrapping tape around the outer circumference of the electrode assembly, although effective in combining a plurality of stacked battery cells into one, is insufficient for suppressing the bending phenomenon of the electrode assembly impregnated with an electrolyte or suppressing the swelling phenomenon during use. Summary of the Invention

[0008] Technical Problem

[0009] The object of the present disclosure is to provide an electrode assembly winding device and an electrode assembly winding method, which can suppress the bending phenomenon of the electrode assembly impregnated with electrolyte or the bulging phenomenon during use by firmly fixing each battery cell of the electrode assembly stacked with a plurality of battery cells to each other.

[0010] In addition, another object of the present disclosure is to provide a battery cell winding device and an electrode assembly winding method, which can solve the problems of wrinkles on the surface of the film or damage to the battery cells during the winding process for ensuring that the battery cells are in a fixed state.

[0011] However, the technical problems to be solved by the present disclosure are not limited to the above problems, and those skilled in the art can clearly understand other problems not mentioned from the description of the present disclosure described below.

[0012] Technical solution

[0013] The present disclosure relates to an electrode assembly winding device. In one example, the electrode assembly winding device includes: a lower table, on the upper surface of which there are a plurality of sealing rods and the lower table can move up and down; a pair of side sealing blocks arranged on both sides of the lower table and capable of moving back and forth relative to the lower table; and an upper table, on the lower surface of which there are a plurality of sealing rods, and the upper table is arranged on the top of the lower table and can move up and down relative to the lower table.

[0014] In one embodiment of the present disclosure, the side sealing block may form a suction hole on the sealing surface.

[0015] In addition, the distance between the plurality of sealing rods in the lower table and the distance between the plurality of sealing rods in the upper table may be adjustable.

[0016] In addition, a film table and / or a battery cell table may be provided outside the pair of side sealing blocks based on the lower table.

[0017] The film table and the battery cell table may include a film library and a battery cell library that respectively stack and accommodate a plurality of films and a plurality of electrode assemblies.

[0018] In addition, the upper table may be installed on an XY table arranged along the XY plane parallel to the sealing surface of the lower table, so that the upper table can move relative to the lower table in three dimensions.

[0019] In addition, the upper table may include a carrier, which successively clamps the films and electrode assemblies respectively stacked and accommodated in the film library and the battery cell library and moves them to the lower table.

[0020] The present disclosure relates to a method for wrapping an electrode assembly, comprising: placing a cut first film above a plurality of sealing rods provided on the upper surface of a lower stage; aligning and placing the electrode assembly above the first film; moving the upper stage downward such that a plurality of sealing rods provided on the bottom surface of the upper stage contact the electrode assembly; bringing the lower stage and the upper stage into close contact with the electrode assembly while moving downward as a whole, so that a pair of side sealing blocks attach the first film protruding from the side of the sealing rods to the side of the electrode assembly, and operating the sealing rods and the side sealing blocks of the lower stage to attach the first film to the bottom surface and the side of the electrode assembly; in the case where the upper stage deviates relative to the lower stage, aligning and placing a cut second film on the upper surface of the electrode assembly; moving the upper stage downward such that a plurality of sealing rods provided in the upper stage contact the second film; and bringing the lower stage and the upper stage into close contact with the electrode assembly while moving downward as a whole to below the side sealing blocks and then moving upward, so that the side sealing blocks attach the second film protruding from the side of the sealing rods to the side of the electrode assembly, and operating the sealing rods and the side sealing blocks of the upper stage to attach the second film to the upper surface and the side of the electrode assembly.

[0021] The pair of side sealing blocks are provided on both sides of the lower stage so as to be movable back and forth relative to the lower stage and move toward the lower stage to attach the first film and the second film to the side of the electrode assembly.

[0022] Furthermore, during attaching the first film and the second film to the side of the electrode assembly, the pair of side sealing blocks may apply a negative pressure to make the first film and the second film adhere to the sealing surface, thereby preventing wrinkles.

[0023] In addition, the spacing between the plurality of sealing rods provided in the lower stage and the spacing between the plurality of sealing rods provided in the upper stage may be adjustable to correspond to the width of the electrode assembly.

[0024] According to an embodiment of the present disclosure, the electrode assembly, the first film, and the second film are respectively stacked and accommodated in a film library and a cell library, and are clamped one by one by a carrier and movable to the lower stage.

[0025] Furthermore, the first film and the second film may include an adhesive layer activated by heating, and after wrapping the bottom surface, the upper surface, and the side of the electrode assembly, heat may be applied to the first film and the second film to make the first film and the second film adhere to the electrode assembly.

[0026] In one embodiment, the adhesive layer is an ethylene-vinyl acetate (EVA) layer, and the EVA layer can be activated for adhesion within a temperature range of 140 ± 20 °C.

[0027] The wrapping method according to the present disclosure includes a series of steps as described above, providing an electrode assembly including: a plurality of battery cells stacked therein; a first film attached to the bottom surface and both sides of the electrode assembly; and a second film attached to the top surface and both sides of the electrode assembly.

[0028] Here, on both sides of the electrode assembly, the second film may be overlapped and attached to the first film.

[0029] For example, the first film and the second film may be polyethylene terephthalate (PET) films.

[0030] In addition, an adhesive layer may be interposed between the first film, the second film and the electrode assembly.

[0031] For example, the adhesive layer may be an EVA layer, and the EVA layer can be activated for adhesion by heating.

[0032] In addition, the first film and the second film may wrap the bottom surface, the top surface and both sides of the electrode assembly so that they are not exposed.

[0033] In addition, the first film and the second film apply a compressive force across the bottom surface, the top surface and both sides of the electrode assembly.

[0034] Beneficial effects

[0035] According to the electrode assembly wrapping device and wrapping method of the present disclosure having the same structure as described above, it enables the film to be precisely attached to the surface of the electrode assembly through a lower stage and an upper stage each having a plurality of sealing rods and a pair of side sealing blocks.

[0036] In addition, through the suction holes provided in the side sealing blocks, the film can be adhered while sucking the side surface of the film under negative pressure, thereby effectively preventing wrinkles from appearing on the surface of the film attached to a small area.

[0037] In addition, the electrode assembly manufactured by the electrode assembly wrapping device and wrapping method of the present disclosure can exhibit strong resistance to bending or bulging phenomena of the electrode assembly because each stacked battery cell is firmly fixed to each other by the wrapped film.

[0038] However, the technical effects that can be obtained through the present disclosure are not limited to the above effects, and other effects not mentioned can be clearly understood by those skilled in the art through the description of the present disclosure described below. Description of the drawings

[0039] The following drawings attached to this specification illustrate exemplary embodiments of the present disclosure and are used to facilitate understanding of the technical concept of the present disclosure together with the following detailed description of the present disclosure. Therefore, the exemplary embodiments of the present disclosure should not be limited to the interpretation based on the drawings.

[0040] Figure 1 is a view showing an external view of a wrapping device according to an embodiment of the present disclosure.

[0041] Figure 2 is a perspective view showing the main structure of the wrapping device.

[0042] Figure 3 is a perspective view of the wrapping device observed from another direction.

[0043] Figure 4 is a front view of the wrapping device.

[0044] Figures 5 to 10 is a view showing a series of steps of attaching a film to the surface of an electrode assembly using the wrapping device according to an embodiment of the present disclosure.

[0045] Figure 11 is a view showing an example of an electrode assembly completed by the wrapping method of the present disclosure.

[0046] Figure 12 is a view showing another example of an electrode assembly completed by the wrapping method of the present disclosure. Detailed Embodiments

[0047] The present disclosure can have various modifications and various embodiments, and thus specific embodiments thereof will be described in detail below.

[0048] However, it should be understood that the present disclosure is not limited to specific embodiments, and includes all modifications, equivalents or alternatives within the spirit and technical scope of the present disclosure.

[0049] As used herein, the terms "comprising", "including" and "having" indicate the presence of features, quantities, steps, actions, components or elements described in the specification or combinations thereof, and it should be understood that the possibility of the existence or addition of one or more other features, quantities, steps, actions, components, elements or combinations thereof is not precluded in advance.

[0050] In addition, in the present disclosure, when a part of a layer, film, region, plate, etc. is disposed “on” another part, this includes not only the case where one part is directly disposed on another part, but also the case where another part is interposed therebetween. Conversely, when a part of a layer, film, region, plate, etc. is disposed “under” another part, this includes not only the case where one part is directly disposed under another part, but also the case where another part is interposed therebetween. Further, in the present application, “on” may include not only the case of being disposed in the upper part, but also the case of being disposed in the lower part.

[0051] The present disclosure relates to an electrode assembly wrapping device. In one example, the electrode assembly wrapping device includes: a lower table having a plurality of sealing rods on an upper surface and capable of moving up and down; a pair of side sealing blocks disposed on both sides of the lower table and capable of moving back and forth relative to the lower table; and an upper table having a plurality of sealing rods on a lower surface and disposed on top of the lower table and capable of moving up and down relative to the lower table.

[0052] Further, in an embodiment of the present disclosure, the side sealing block may be formed with suction holes on a sealing surface.

[0053] By using the electrode assembly wrapping device having the above-described configuration, the film can be precisely attached to the surface of the electrode assembly by the lower table and the upper table each having a plurality of sealing rods and a pair of side sealing blocks.

[0054] In addition, the film can be attached while sucking the side surface of the film by negative pressure through the suction holes provided in the side sealing blocks, thereby effectively preventing wrinkles from appearing on the surface of the film attached to a small area.

[0055] Modes for Implementing the Present Invention

[0056] Hereinafter, specific embodiments of the present disclosure will be described in detail with reference to the drawings.

[0057] [First Embodiment]

[0058] Figure 1 FIG. is a view showing an external view of an electrode assembly wrapping device 10 (hereinafter, simply referred to as “wrapping device”) according to an embodiment of the present disclosure. In Figure 1 the wrapping device 10, as an example, main devices, components, etc. are installed in a space inside a cabinet 12, and the internal main components are protected from various foreign matters such as dust by the closed structure of the cabinet 12. The main components are fixed and supported in a frame 14 installed longitudinally inside the cabinet 12, and the electrode assembly 520 and the film 420 can be supplemented, inspected, repaired, etc. through doors provided at various positions.

[0059] Figure 2 and Figure 3 is a perspective view showing the main structure of the wrapping device 10 installed in the cabinet 12, Figure 4 and is a front view of the wrapping device. The shown wrapping device 10 mainly includes a lower table 100, a pair of side seal blocks 200, and an upper table 300.

[0060] The lower table 100 has a plurality of seal rods 110 on its upper surface and can move up and down in the Z-axis direction (height direction) in the figure. The seal rods 110 are components that generate and supply the heat required to attach the film 420 to the surface of the electrode assembly 520.

[0061] The pair of side seal blocks 200 are arranged on both sides of the lower table 100. The side seal blocks 200 are sealing devices for attaching the film 420 to both sides of the electrode assembly 520, and the heating temperature of the sealing surface 210 corresponds to the heating temperature of the seal rods 110 of the lower table 100. In addition, each of the pair of side seal blocks 200 can move back and forth relative to the lower table 100. The back-and-forth movement of the side seal blocks 200 is performed together with the up-and-down movement of the lower table 100 and the upper table 300 described below, and the film 420 is attached to the top surface, bottom surface, and both sides of the electrode assembly 520 through this associated back-and-forth movement and up-and-down movement.

[0062] The upper table 300 is arranged above the lower table 100, and the bottom surface of the upper table 300 is provided with seal rods 310 corresponding to the seal rods 110 of the lower table 100. The seal rods of the upper table 300 are also heated to a temperature corresponding to the heating temperature of the seal rods 110 of the lower table 100. The upper table 300 can move up and down relative to the lower table 100, and during the wrapping process, the lower table 100 and the upper table 300 fix the electrode assembly 520 located therebetween and apply an appropriate sealing pressure.

[0063] The up-and-down movement of the lower table 100 and the upper table 300 can be achieved by a conventional cylinder device. The cylinder device can be electric, hydraulic, pneumatic, etc., and in the embodiments of the present disclosure, the up-and-down movement of the lower table 100 and the upper table 300 can preferably be pneumatic because the suction holes 220 of the side seal blocks 200 (to be described below) use air pressure. The sealing pressure of the pneumatically operated lower table 100 and upper table 300 will correspond to the air pressure, and the sealing pressure can be approximately in the range of 3 ± 0.2 bar. For the same reason, the pair of side seal blocks 200 can also move back and forth pneumatically.

[0064] Refer to Figure 2Partial enlarged view of the side seal block 200 in []. A plurality of suction holes 220 are formed on the sealing surface 210 of the side seal block 200. During the wrapping operation of the wrapping device 10, the side seal block 200 enters the lower stage 100 and attaches the film 420 to the narrow area of the electrode assembly 520. By attaching the end of the film 420 to the narrow area, wrinkles are likely to occur in the film 420 during the attachment process. Since the wrinkles that occur in the film 420 during the wrapping process are defect factors, it is necessary to prevent them. For this purpose, the present disclosure provides a plurality of suction holes 220 on the sealing surface 210 of the side seal block 200. In other words, the side seal block 200 adsorbs the film 420 by the negative pressure generated by the suction holes 220, and keeps the film 420 in a taut state during the attachment, so that no wrinkles occur even when the front end of the film 420 is attached to the side of the electrode assembly 520.

[0065] In addition, referring to Figures 2 to 4 , the sealing rods 110 and 310 respectively provided on the lower stage 100 and the upper stage 300 are exemplarily three in number. According to an embodiment of the present disclosure, wherein the sealing rods 110 and 310 are multiple, the spacing between the sealing rods 110 and 310 can be configured to be adjustable. For example, among the three sealing rods 110 and 310, the area occupied by the entire sealing rods 110 and 310 can be changed by linearly moving the sealing rods on both sides around the central sealing rod. The area formed by the multiple sealing rods 110 and 310 corresponds to the width of the electrode assembly 520. In other words, by adjusting the spacing between the multiple sealing rods 110 and 310, it is possible to wrap various specifications of electrode assemblies 520 with different width dimensions. Of course, corresponding to the adjustment of the spacing between the sealing rods 110 and 310, the distance of the forward and backward movement of the pair of side seal blocks 200 is also adjusted.

[0066] Meanwhile, based on the lower stage 100, a film stage 400 and / or a cell stage 500 can be provided on the outer sides of the pair of side seal blocks 200 to effectively perform the wrapping process sequentially for the multiple electrode assemblies 520. The film stage 400 and the cell stage 500 each include a film library 410 and a cell library 510, in which a plurality of films 420 and electrode assemblies 520 are stacked and accommodated.

[0067] In addition, the upper stage 300 can be installed on an XY stage 600 provided along the XY plane parallel to the sealing surface 210 of the lower stage 100, so that the upper stage 300 is configured to achieve three-dimensional relative movement with respect to the lower stage 100. The XY stage 600 is fixedly installed on a frame 14 installed in the cabinet 12, and the upper stage 300 suspended on the XY stage 600 can move to any position along the XY plane. Moreover, as described above, the upper stage 300 can move up and down relative to the lower stage 100, so the upper stage 300 can move three-dimensionally in the XYZ space relative to the lower stage 100.

[0068] The upper stage 300 capable of performing such three-dimensional movement may be provided with a carrier 700 corresponding to the installation of the film stage 400 and / or the battery cell stage 500. The carrier 700 is used to successively grip and move the films 420 and the electrode assemblies 520 respectively stacked and accommodated in the film library 410 and the battery cell library 510 onto the lower stage 100. Through the configuration of the carrier 700, the film stage 400, and / or the battery cell stage 500, the wrapping operation of multiple electrode assemblies 520 can be automatically and effectively performed.

[0069] In addition, the sealing rods 110 of the lower stage 100, the sealing rods 310 of the upper stage 300, and the sealing surfaces 210 of the side sealing blocks 200 may have heating members, such as electric heating wires, embedded therein. The heating members embedded in the sealing surfaces 210 of each of the sealing rods 110, 310 of the lower stage 100 and the upper stage 300 and the side sealing blocks 200 may be provided to activate the adhesive layer 430 (refer to Figure 12 ) provided on the surface of the film 420.

[0070] When wrapping the upper surface, bottom surface, and both sides of the electrode assembly 520 with the film 420, if the adhesive layer 430 on the surface of the film 420 has viscosity, the wrapping becomes difficult and the risk of defects becomes very high. Therefore, it may be necessary to form the adhesive layer 430 on the attachment surface of the film 420 using a material that remains smooth and non-sticky at room temperature but activates the adhesive function only when heated to a specific temperature. This will be described in detail in the second embodiment below.

[0071] [Second Embodiment]

[0072] Referring to Figures 1 to 4 , the structure of the wrapping device 10 has been described in detail in the first embodiment. Subsequently, in the second embodiment, a method of wrapping the electrode assembly by attaching the film 420 to the surface of the electrode assembly 520 using the above-mentioned wrapping device 10 (hereinafter, simply referred to as the "wrapping method") will be described. Figures 5 to 10 FIG. is a diagram showing a series of steps of attaching the film 420 to the surface of the electrode assembly 520 using the wrapping device 10 of the present disclosure. According to the drawings and the description, the wrapping method of the electrode assembly 520 according to the present disclosure will be clearly understood.

[0073] Figure 5 FIG. shows the step of placing the first film 421 cut to a certain size for the electrode assembly 520 above the plurality of sealing rods 110 provided on the upper surface of the lower stage 100, and the step of aligning and placing the electrode assembly 520 above the first film 421. In Figure 5 this step, the lower stage 100 is raised to a position suitable for placing the first film 421 and the electrode assembly 520, and a pair of side sealing blocks 200 move backward.

[0074] Figure 6 shows the next step, where the upper stage 300 moves downward such that a plurality of sealing rods 310 provided on the bottom surface of the upper stage 300 contact the electrode assembly 520 placed above the sealing rod 110 of the lower stage 100. Thus, in Figure 6 this step, the sealing rod 310 of the upper stage 300, the electrode assembly 520, the first film 421, and the sealing rod 110 of the lower stage 100 are positioned from top to bottom, and the upper stage 300 and the lower stage 100 are pressed and fixed to the electrode assembly 520 and the first film 421 under a pressure suitable for attaching the first film 421 (such as a pressure in the range of 3 ± 0.2 bar).

[0075] In addition, referring to Figure 6 and Figure 7 , when the lower stage 100 and the upper stage 300 are brought into contact with the electrode assembly 520, at an appropriate time, a pair of side sealing blocks 200 move forward such that their sealing surfaces 210 are in positions corresponding to the sides of the electrode assembly 520. In this case, the sealing surfaces 210 of the side sealing blocks 200 are located below the first film 421 and the electrode assembly 520. In this state, when the lower stage 100 and the upper stage 300 move downward as a whole, the pair of side sealing blocks 200 attach the first film 421 protruding from the sides of the sealing rods 110, 310 to the sides of the electrode assembly 520, and attach the first film 421 to the bottom surface and the sides of the electrode assembly 520 by operating and heating the sealing rod 110 of the lower stage 100 and the side sealing blocks 200.

[0076] After attaching the first film 421, the process of attaching the second film 422 is then performed. As Figure 8 shown, in order to place the second film 422 on the upper surface of the electrode assembly 520, the upper stage moves upward and deviates from the lower stage 100, and the similarly cut second film 422 is aligned and placed on the exposed upper surface of the electrode assembly 520.

[0077] Similar to the above Figure 6 , Figure 9 shows the upper stage 300 moving downward such that a plurality of sealing rods 310 provided on the upper stage 300 contact the second film 422. Here, different from the case of attaching the first film 421 in Figure 6 , the second film 422 is located below the sealing surface 210 of the side sealing blocks 200. This is because the second film 422 is located above the upper surface of the electrode assembly 520, so the force for attaching the front end of the second film 422 to the side of the electrode assembly 520 should act in the opposite direction to Figure 6 the case. Therefore, a pair of side sealing blocks 200 should move forward after the lower stage 100 and the upper stage 300 move downward as a whole and the second film 422 is positioned below the sealing surface 210.

[0078] Figure 10 shows the final process of attaching the second film 422, in which the lower stage 100 and the upper stage 300 are in close contact with the electrode assembly 520, while moving integrally upward from below the sealing surface 210 of the side sealing block 200, so that the side sealing block 200 fits the second film 422 protruding from the sides of the sealing rods 110, 310 to the side of the electrode assembly 520. In this state, the sealing rod 310 of the upper stage 300 and the side sealing block 200 are heated to attach the second film 422 to the upper surface and the side of the electrode assembly 520.

[0079] In the wrapping method including such a series of steps, various configurations of the wrapping device 10 described in the first embodiment can be used. For example, a pair of side sealing blocks 200 can apply negative pressure during attaching the first film 421 and the second film 422 to the side of the electrode assembly 520 to make them fit to the sealing surface 210 and prevent wrinkling. In addition, the spacing between the plurality of sealing rods 110, 310 provided on the lower stage 100 and the upper stage 300 can be adjusted corresponding to the width of the electrode assembly 520, and the films 420 and the electrode assemblies 520 respectively stacked and accommodated in the film library 410 and the battery cell library 510 can be individually clamped by the carrier 700 and moved onto the lower stage 100.

[0080] Figure 11 is a diagram showing an example of the electrode assembly 520 completed using the wrapping method of the present disclosure described with reference to Figures 5 to 10 The shown electrode assembly 520 refers to the electrode assembly 520 with the attached film 420, in other words, the electrode assembly 520 after the wrapping process, and includes the electrode assembly 520 having a plurality of battery cells stacked, the first film 421 attached to the bottom surface and both sides of the electrode assembly 520, and the second film 422 attached to the upper surface and both sides of the electrode assembly 520. The first film 421 and the second film 422 can be films 420 made of a material that is thin while having excellent various strengths (tensile strength, breaking strength, etc.), such as a polyethylene terephthalate (PET) film.

[0081] In addition, with reference to Figure 11 both sides of the shown electrode assembly 520, the second film 422 covering the upper surface of the electrode assembly 520 is overlapped and attached above the first film 421. It will be easily understood that such an overlapping structure of the films 421, 422 on both sides of the electrode assembly 520 is generated by the above wrapping method.

[0082] In addition, Figure 12 is a diagram showing another example of the electrode assembly 520 completed using the wrapping method of the present disclosure. Although the basic attachment structure of the electrode assembly 520 and the film 420 is the same, there are some differences in the configuration.Figure 12 The characteristic configuration of the electrode assembly 520 is described as follows.

[0083] The first film 421 and the second film 422 include an adhesive layer 430 activated by heating. The adhesive layer 430 is formed on the surface (attachment surface) to which the first film 421 and the second film 422 are attached to the electrode assembly 520. The adhesive layer 430 is preferably composed of a material that remains smooth and non-sticky at room temperature but activates the adhesive function when heated to a specific temperature. For example, the adhesive layer may be an EVA (ethylene-vinyl acetate) layer, and the adhesive action of the EVA layer can be activated within a temperature range of 140 ± 20°C. Due to this characteristic of the adhesive layer 430, the film 420 can be attached to the surface of the electrode assembly 520 flat and smoothly, without wrinkles, bubbles, etc. as described above.

[0084] The adhesive layer 430 such as an EVA layer provided in the film 420 has its adhesive function activated after the wrapping of the bottom surface, the top surface, and the sides of the electrode assembly 520 is completed, which may be desirable in preventing defects such as the occurrence of wrinkles. Therefore, in the wrapping method according to an embodiment of the present disclosure, the heating members embedded in the sealing surfaces 210 of each of the sealing rods 110, 310 of the lower table 100 and the upper table 300 and the side sealing block 200 can be operated as a step after applying the film 420 having the adhesive layer 430 activated by heating, provided that the first film 421 and the second film 422 wrap both the bottom surface and the top surface as well as the sides of the electrode assembly 520. By heating to activate the adhesive layer 430, the wrapping process of the film 420 on the electrode assembly 520 is completed more firmly.

[0085] In addition, referring to Figure 12 , the first film 421 and the second film 422 can be attached to the electrode assembly 520 with a larger area without exposing the bottom surface, the top surface, and both sides of the electrode assembly 520. In other words, the first film 421 and the second film 422 can be attached across the entire full-width direction of the electrode assembly 520. In fact, considering any alignment errors that may occur between the first film 421 and the second film 422 and the electrode assembly 520 on the wrapping device 10, the first film 421 and the second film 422 can have a width exceeding the full width of the electrode assembly 520, such as a width corresponding to approximately 105% to 110% of the full width of the electrode assembly 520.

[0086] The first film 421 and the second film 422 can be closely attached to the bottom surface and the upper surface of the electrode assembly 520 and span both sides thereof, so as to apply a uniform compressive force around the electrode assembly 520. This compressive force of the film 420 can be further enhanced with the assistance of the adhesive layer 430. In the conventional tape winding process of winding the electrode assembly 520 with a tape, the tape applies a local fixing force on the electrode assembly 520, and the adhesiveness of the tape is insufficient and uneven. In contrast, in the electrode assembly 520 manufactured by the winding device 10 and the winding method according to the embodiments of the present disclosure, the fixing force of the film 420 is uniformly applied over a large area in the entire width direction, so that each stacked battery cell is firmly fixed to each other by the wound film, and thus the electrode assembly 520 exhibits strong resistance to bending phenomena, swelling phenomena, etc.

[0087] In particular, the electrode assembly 520 manufactured by the winding device 10 and the winding method according to the embodiments of the present disclosure can reliably fix a plurality of battery cells to each other through the film 420 attached in the entire width direction and by a pair of side sealing blocks 200 that apply a negative pressure while attaching the first film 421 and the second film 422 to the sides of the electrode assembly 520, without causing defects such as wrinkles or bubbles in the film 420 during the winding process. In addition, with the assistance of the adhesive layer 430 activated by heating, the attachment of the film 420 to the electrode assembly 520 can be stably maintained for a long time, thereby improving the stability of the electrode assembly 520.

[0088] As described above, the present disclosure has been described in more detail through the drawings and embodiments. However, since the configurations described in the drawings or embodiments described herein are only one embodiment of the present disclosure and do not represent the overall technical idea of the present invention, it should be understood that the present disclosure covers various equivalents, modifications, and substitutions at the time of filing of this application.

[0089] [Description of Reference Numerals]

[0090] 10: Winding device 12: Cabinet

[0091] 14: Frame 100: Lower stage

[0092] 110: Sealing rod 200: Side sealing block

[0093] 210: Sealing surface 220: Suction hole

[0094] 300: Upper stage 310: Sealing rod

[0095] 400: Film stage 410: Film library

[0096] 420: Film 421: First film

[0097] 422: Second film 430: Adhesive layer

[0098] 500: Battery cell stage 510: Battery cell storage

[0099] 520: Electrode assembly 600: XY stage

[0100] 700: Carrier

Claims

1. An electrode assembly wrapping device, the electrode assembly wrapping device comprising: A lower table, having a plurality of sealing rods on the upper surface thereof and capable of moving up and down; A pair of side sealing blocks disposed on both sides of the lower table and capable of moving back and forth relative to the lower table; And An upper table, having a plurality of sealing rods on the lower surface thereof, and the upper table is disposed on top of the lower table and capable of moving up and down relative to the lower table.

2. The electrode assembly wrapping device according to claim 1, wherein, Suction holes are formed on the sealing surfaces of the side sealing blocks.

3. The electrode assembly wrapping device according to claim 1, wherein, The spacing between the plurality of sealing rods disposed in the lower table and the spacing between the plurality of sealing rods disposed in the upper table are adjustable.

4. The electrode assembly wrapping device according to claim 1, wherein, Based on the lower table, a film table and / or a battery cell table are disposed outside the pair of side sealing blocks.

5. The electrode assembly wrapping device according to claim 4, wherein, The film table and the battery cell table include a film library and a battery cell library that respectively stack and accommodate a plurality of films and a plurality of electrode assemblies.

6. The electrode assembly wrapping device according to claim 5, wherein, The upper table is mounted on an XY table disposed along the XY plane parallel to the sealing surface of the lower table, so that the upper table can move relative to the lower table in three dimensions.

7. The electrode assembly winding device according to claim 6, wherein, The upper table includes a carrier that successively clamps the films and electrode assemblies respectively stacked and accommodated in the film library and the battery cell library and moves them to the lower table.

8. An electrode assembly wrapping method, the electrode assembly wrapping method comprising the following steps: Placing the cut first film above a plurality of sealing rods provided on the upper surface of the lower table; Aligning and placing the electrode assembly above the first film; Moving the upper table downward so that a plurality of sealing rods provided on the bottom surface of the upper table contact the electrode assembly; Bringing the lower table and the upper table into close contact with the electrode assembly while moving downward as a whole, so that a pair of side sealing blocks attach the first film protruding from the side of the sealing rod to the side of the electrode assembly, and operating the sealing rods and the side sealing blocks of the lower table to attach the first film to the bottom surface and side surface of the electrode assembly; In the case where the upper table deviates from the lower table, aligning and placing the cut second film on the upper surface of the electrode assembly; Moving the upper table downward so that a plurality of sealing rods provided in the upper table contact the second film; And Bringing the lower table and the upper table into close contact with the electrode assembly while moving downward as a whole to below the side sealing blocks and then moving upward, so that the side sealing blocks attach the second film protruding from the side of the sealing rod to the side of the electrode assembly, and operating the sealing rods and the side sealing blocks of the upper table to attach the second film to the upper surface and side surface of the electrode assembly.

9. The method for wrapping the electrode assembly according to claim 8, wherein, The pair of side sealing blocks are disposed on both sides of the lower table to be capable of moving back and forth relative to the lower table and moving toward the lower table to attach the first film and the second film to the side surface of the electrode assembly.

10. The method for wrapping an electrode assembly according to claim 9, wherein, During the attachment of the first film and the second film to the side surface of the electrode assembly, the pair of side sealing blocks apply a negative pressure to make the first film and the second film fit to the sealing surface, thereby preventing wrinkles.

11. The method for wrapping the electrode assembly according to claim 8, wherein, The spacing between the plurality of sealing rods disposed in the lower table and the spacing between the plurality of sealing rods disposed in the upper table can be adjusted to correspond to the width of the electrode assembly.

12. The method for wrapping an electrode assembly according to claim 8, wherein, The electrode assembly, the first film, and the second film are respectively stacked and accommodated in a film library and a battery cell library, and are clamped one by one by a carrier and moved onto the lower table.

13. The method for wrapping an electrode assembly according to claim 8, wherein, The first film and the second film include an adhesive layer activated by heating, and After wrapping the bottom surface, the upper surface, and the sides of the electrode assembly, heat is applied to the first film and the second film, so that the first film and the second film are adhered to the electrode assembly.

14. The method for wrapping an electrode assembly according to claim 13, wherein, The adhesive layer is an ethylene-vinyl acetate (EVA) layer, wherein the EVA layer is activated and adhered within a temperature range of 140 ± 20 °C.

15. An electrode assembly, the electrode assembly comprising: A plurality of battery cells stacked therein; A first film attached to the bottom surface and both sides of the electrode assembly; And A second film attached to the upper surface and both sides of the electrode assembly.

16. The electrode assembly according to claim 15, wherein, On both sides of the electrode assembly, the second film is overlapped and attached to the first film.

17. The electrode assembly according to claim 15, wherein, The first film and the second film are polyethylene terephthalate (PET) films.

18. The electrode assembly according to claim 15, wherein, An adhesive layer is interposed between the first film and the electrode assembly and between the second film and the electrode assembly.

19. The electrode assembly according to claim 18, wherein, The adhesive layer is an EVA layer, and The EVA layer is activated and adhered by heating.

20. The electrode assembly according to claim 15, wherein The first film and the second film prevent the bottom surface, the upper surface, and both sides of the electrode assembly from being exposed.

21. The electrode assembly according to claim 15, wherein, The first film and the second film apply a compressive force across the bottom surface, the upper surface, and both sides of the electrode assembly.

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