Electrode assembly manufacturing device including ultrasonic cutter and electrode assembly manufacturing method using the same

Abstract

The present invention relates to an electrode assembly manufacturing device, comprising: an electrode plate supply unit for supplying an electrode plate having an electrode mixture coated portion and an electrode mixture non-coated portion formed thereon; a cutting unit disposed at the rear of the electrode plate supply unit for forming electrode tabs on the electrode plate; and a laminating unit disposed at the rear of the electrode plate supply unit for laminating the stacked positive and negative electrodes with a separator interposed between the positive and negative electrodes, wherein the cutting unit includes a mold for supporting the electrode plate and an ultrasonic cutter disposed separately from the mold, the ultrasonic cutter being used to form the electrode tabs, the cutting edge of the ultrasonic cutter being formed to correspond to the outer periphery of a unit electrode in a direction in which the electrode tabs are formed, the cutting unit and the laminating unit being disposed on the same processing line to perform continuous processing. Therefore, the space required for manufacturing the electrode assembly can be reduced, and deformation of the electrode plate foil and damage to the electrode mixture layer can be prevented in the cut cross-section of the electrode plate.

Description

Technical Field

[0001] This application claims priority from Korean Patent Application No. 2020-0117858, filed on September 14, 2020, the disclosure of which is incorporated herein by reference in its entirety.

[0002] The present invention relates to an electrode assembly manufacturing apparatus including an ultrasonic cutter and an electrode assembly manufacturing method using the apparatus. More specifically, the present invention relates to an electrode assembly manufacturing apparatus including an ultrasonic cutter capable of cutting an electrode mixture-coated portion and an electrode mixture-uncoated portion to form an electrode tab on an electrode plate, and an electrode assembly manufacturing method using the apparatus. Background Art

[0003] Secondary batteries that can be repeatedly charged and discharged have an advantage of a long battery cell life, and are used in a manner such that the secondary batteries are detachably attached to devices or built into devices. The types of devices using secondary batteries as energy sources have increased.

[0004] In particular, for lithium secondary batteries that are charged and discharged due to the movement of lithium ions, since lithium secondary batteries have the advantages of high energy density and high charging voltage, lithium secondary batteries are not only used in the field of small battery cells for use in mobile devices or small electronic products, but also in the field of medium or large battery packs used as energy sources for electric vehicles or power storage systems that require high output and high voltage.

[0005] Based on the shape of the battery case, lithium secondary batteries are divided into cylindrical secondary batteries having an electrode assembly mounted in a cylindrical metal can, prismatic secondary batteries having an electrode assembly mounted in a prismatic metal can, or pouch-shaped secondary batteries having an electrode assembly mounted in a pouch-shaped case made of an aluminum laminate.

[0006] The electrode assembly is formed by stacking positive electrodes and negative electrodes with a separator inserted between the positive electrodes and the negative electrodes, and the positive electrodes and negative electrodes are formed by forming electrode tabs on each of the positive electrode plates and the negative electrode plates and cutting each of the positive electrode plates and the negative electrode plates into unit electrodes.

[0007] Conventionally, the electrode tabs are formed by a punching method of removing the remaining portion of the non-coated portion of the electrode plate except for the electrode tabs.

[0008] In particular, a pressure cutter is placed on the electrode plate, the pressure cutter comprising an upper cutter and a lower cutter, and the upper cutter is used to perform punching to notch the electrode plate to form an electrode tab. However, if a pressure cutter comprising an upper cutter and a lower cutter is used, the distance between the upper cutter and the lower cutter must be kept at zero. As a result, a large amount of time is spent on maintaining the pressure cutter. In addition, during punching, the electrode mixture layer is easily broken due to the pressure applied to the electrode plate, and the electrode mixture layer may be separated from the electrode plate.

[0009] Furthermore, burrs may be generated on the cut cross-section of the electrode plate foil, or the cut cross-section of the electrode plate foil may be deformed, thereby possibly deteriorating the quality of the cut cross-section of the electrode plate foil.

[0010] Furthermore, due to the vibrations generated during the punching process using the press cutter, the electrode plate from which the electrode tabs are formed by cutting is wound into a reel, and the wound electrode plate is transferred to a laminating process line for lamination. As described above, since the cutting and laminating processes must be performed separately, it is necessary to secure a wide space required for the electrode assembly production facility, and automating the entire process for manufacturing the electrode assembly is very difficult.

[0011] In this regard, patent document 1 discloses an ultrasonic cutting device, which is used to cut a part of a precursor of a secondary battery, such as a positive electrode protrusion and a negative electrode protrusion. The precursor of the secondary battery includes a plurality of stacked power generation elements, each power generation element including a stack of positive electrodes, separators, and negative electrodes, the positive electrode having a positive electrode protrusion for terminal connection, and the negative electrode having a negative electrode protrusion for terminal connection.

[0012] The ultrasonic cutting device of Patent Document 1 cuts the positive and negative electrode protrusions while the power generating elements are stacked. However, no method for cutting the positive and negative electrodes from the electrode plates is provided, and the ultrasonic cutting device only cuts the non-coated portions of the positive and negative electrodes.

[0013] Thus, there is a need for an electrode plate cutter that can prevent separation of the electrode mixture layer and deformation of the electrode plate foil when cutting the electrode mixture coated portion.

[0014] (Prior art literature)

[0015] (Patent Document 1) Japanese Patent Application Publication No. 2018-09468 (June 21, 2018) Summary of the Invention

[0016] Technical issues

[0017] The present invention is made in view of the above problems, and the purpose of the present invention is to provide an electrode assembly manufacturing device and an electrode assembly manufacturing method using the device that can prevent deformation of the electrode plate foil and damage to the electrode mixture coating part during the process of cutting the electrode plate having steps formed due to the electrode mixture coating part, while reducing the facility space required for manufacturing the electrode assembly.

[0018] Technical Solution

[0019] In order to achieve the above-mentioned purpose, the electrode assembly manufacturing device according to the present invention includes: an electrode plate supply unit for supplying electrode plates formed with an electrode mixture coated portion and an electrode mixture non-coated portion; a cutting unit arranged at the rear of the electrode plate supply unit for forming electrode tabs on the electrode plates; and a laminating unit arranged at the rear of the electrode plate supply unit for laminating the stacked positive electrodes and negative electrodes in a state where a separator is inserted between the positive electrode and the negative electrode, wherein the cutting unit includes a mold for supporting the electrode plate and an ultrasonic cutter arranged separately from the mold, the ultrasonic cutter is used to form the electrode tabs, the cutting line of the cutting blade of the ultrasonic cutter is formed to correspond to the outer periphery of the unit electrode in the direction of forming the electrode tabs, and the cutting unit and the laminating unit are arranged on the same processing line to perform continuous processing.

[0020] In the electrode assembly manufacturing apparatus according to the present invention, the ultrasonic cutter may further include an auxiliary cutting edge for forming a recess for guiding the cutting of the unit electrode.

[0021] The electrode assembly manufacturing apparatus according to the present invention may further include an electrode forming unit provided between the cutting unit and the laminating unit, the electrode forming unit being configured to cut the electrode plate to manufacture the unit electrodes.

[0022] In the electrode assembly manufacturing apparatus according to the present invention, a cutting line of the cutting edge of the ultrasonic cutter may be formed to correspond to an outer circumference of the unit electrode.

[0023] In the electrode assembly manufacturing apparatus according to the present invention, the ultrasonic cutter may cut the electrode mixture coated portion.

[0024] In the electrode assembly manufacturing apparatus according to the present invention, the cutting line of the cutting edge of the ultrasonic cutter may be formed in a uniform plane.

[0025] In the electrode assembly manufacturing apparatus according to the present invention, the ultrasonic cutter may be coupled with an inspection member.

[0026] Furthermore, the present invention provides a method for manufacturing an electrode assembly using the electrode assembly manufacturing apparatus.

[0027] In particular, the electrode assembly manufacturing method may include: (a) conveying the electrode plate to the cutting unit, (b) using the ultrasonic cutter to form electrode tabs, (c) cutting the electrode plate into unit electrodes, and (d) laminating the positive electrode and the negative electrode with each other in a state where the separator is inserted between the positive electrode and the negative electrode, wherein steps (a) to (d) can be performed on a continuous processing line.

[0028] In the electrode assembly manufacturing method according to the present invention, step (b) and step (c) may be performed simultaneously.

[0029] In the electrode assembly manufacturing method according to the present invention, step (b) and step (c) may be performed sequentially, step (b) may be performed using a first ultrasonic cutter, and step (c) may be performed using a second ultrasonic cutter.

[0030] In the electrode assembly manufacturing method according to the present invention, the vibration direction of the ultrasonic cutter may be a direction perpendicular to the electrode plate.

[0031] In the electrode assembly manufacturing method according to the present invention, step (b) may include a process of forming a recess for guiding the cutting of the unit electrodes.

[0032] In the electrode assembly manufacturing method according to the present invention, step (b) can be performed by the following process: while the cutting edge of the ultrasonic cutter is placed on the outer surface of the electrode plate, the cutting edge of the ultrasonic cutter is pushed once to form the outer periphery of the unit electrode in the direction of forming the electrode tab.

[0033] Beneficial effects

[0034] As is clear from the above description, in the present invention, an ultrasonic cutter is used to form the electrode tab, thereby preventing deformation of the electrode plate foil or separation of the electrode mixture layer in the cut sections of the electrode mixture coated portion and the electrode mixture non-coated portion.

[0035] Furthermore, a cutting unit and a laminating unit for forming electrode tabs are provided on the same processing line, so that continuous processing can be performed, thereby reducing a space required for an electrode assembly manufacturing facility.

[0036] Furthermore, if the inspection member is coupled to the ultrasonic cutter, the cut cross-section of the electrode plate on which the electrode tab is formed can be inspected while the electrode tab is being formed. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a perspective view of an electrode assembly manufacturing apparatus according to a first embodiment.

[0038] Figure 2 is a perspective view of an ultrasonic cutter according to the present invention.

[0039] Figure 3 This is an enlarged view of the cutting edge of the ultrasonic cutter.

[0040] Figure 4 are plan views showing different shapes of cutting edges.

[0041] Figure 5 is a partially enlarged view showing a portion of the positive electrode plate where a positive electrode tab is formed.

[0042] Figure 6 is a perspective view of a portion of an electrode assembly manufacturing apparatus according to a second embodiment.

[0043] Figure 7 is a perspective view of a portion of an electrode assembly manufacturing apparatus according to a third embodiment.

[0044] Figure 8 is a perspective view showing a cutting blade of an electrode assembly manufacturing apparatus according to a fourth embodiment.

[0045] Figure 9 is an enlarged view of a cut section of an electrode plate cut using a pressure cutter.

[0046] Figure 10 This is a plan view of an electrode plate cut using a pressure cutter.

[0047] Figure 11 This is an enlarged view of a cut section of an electrode plate cut using an ultrasonic cutter.

[0048] Figure 12 This is a plan view of an electrode plate cut using an ultrasonic cutter.

[0049] Figure 13 1 is a diagram showing a comparison of cross sections of a positive electrode plate having an insulating coating cut using a pressure cutter and an ultrasonic cutter.

[0050] Figure 14 FIG. 1 is a diagram showing a comparison of cross sections of negative electrode plates cut using pressure, an ultrasonic cutter, and a laser. DETAILED DESCRIPTION

[0051] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the preferred embodiments of the present invention. However, in the process of describing the operating principles of the preferred embodiments of the present invention in detail, if a detailed description of known functions and structures introduced herein is likely to confuse the subject matter of the present invention, the description will be omitted.

[0052] In addition, the same reference numerals are used throughout the drawings to refer to components that perform similar functions or operations. If a component is referred to as being connected to another component in the specification, the component may be directly connected to the other component or indirectly connected to the other component via other components. In addition, the inclusion of an element does not exclude other elements; on the contrary, unless otherwise specified, it means that these elements may be further included.

[0053] Furthermore, unless otherwise limited, the description embodying elements through limitation or supplementation can be applied to all inventions and does not limit a specific invention.

[0054] Also, in the description of the present invention and the claims of the present application, unless otherwise stated, a singular form shall include a plural form.

[0055] Furthermore, in the specification of the present invention and the claims of this application, unless otherwise stated, "or" includes "and." Therefore, "including A or B" refers to three cases, namely, the case including A, the case including B, and the case including A and B.

[0056] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0057] Figure 1 is a perspective view of an electrode assembly manufacturing apparatus according to a first embodiment, Figure 2 is a perspective view of an ultrasonic cutter according to the present invention.

[0058] Figure 1 A process for manufacturing a single cell having a structure in which one positive electrode and one negative electrode are stacked in a state in which a separator is interposed between the positive electrode and the negative electrode is shown.

[0059] refer to Figure 1 and 2 The electrode assembly manufacturing device 10 includes: an electrode plate supplying unit 100 for supplying an electrode plate formed with an electrode mixture coated portion and an electrode mixture non-coated portion; a cutting unit 200 for forming electrode tabs on the electrode plate; and a laminating unit 300 for laminating the stacked positive electrodes and negative electrodes with a separator inserted between the positive electrodes and the negative electrodes.

[0060] The cutting unit 200 includes an ultrasonic cutter 210 and a mold 220. By using the ultrasonic cutter 210, an electrode tab is formed on the electrode plate moved over the mold 220.

[0061] Figure 2 The ultrasonic cutter 210 shown includes: an oscillator 212 for generating ultrasonic waves; an amplifier 213 for amplifying / reducing vibration energy generated by the oscillator 212; a cutting blade 211 for cutting an electrode plate; and a horn 214 for transmitting vibration energy from the amplifier 213 to the cutting blade 211.

[0062] In a specific example, the cutting speed of the ultrasonic cutter 210 may be set to 200 m / s or less. The ultrasonic wave of the ultrasonic cutter may have an oscillation frequency of 15 kHz to 40 kHz and an amplitude of 10 μm to 60 μm, which may vary depending on the configuration of the electrode plate.

[0063] As described above, in the present invention, an ultrasonic cutter is used to form the electrode tabs, and thus, damage to the electrode plates caused by vibration is relatively small compared to a conventional punching process in which a pressure cutter punch is used to cut the electrode tabs.

[0064] Furthermore, when conventional cutting units use a pressure cutter to cut the electrode plate, the distance between the upper and lower cutters must be maintained at zero, necessitating fine-tuning of the distance between them. However, in the present invention, the ultrasonic cutter's cutting blade is placed on the outer surface of the electrode plate and then pushed to form the electrode tab. Unlike conventional techniques, this process of maintaining the distance between the upper and lower cutters is unnecessary. This reduces the time required to maintain the distance between the upper and lower cutters, as is conventionally done.

[0065] At the same time, in conventional technology, the vibration generated during the cutting process using a pressure cutter is large. Therefore, if the cutting process and the lamination process of aligning and laminating the positive electrode and the negative electrode are performed on the same processing line, the vibration generated during the cutting process may affect the lamination process. Therefore, in conventional technology, the cutting process line and the lamination process line are set separately. In particular, the electrode assembly is manufactured using the following method: the electrode plate that has undergone the cutting process is wound into the form of a reel, the wound electrode plate is transferred to the lamination process line, and the lamination process is performed. Therefore, the cutting process and the lamination process are performed discontinuously.

[0066] However, in the present invention, an ultrasonic cutter that generates a small amount of vibration is used during the electrode tab formation process. Therefore, even if the cutting unit and the laminating unit are arranged on the same processing line, the vibration from the cutting unit has little effect on the laminating unit. Therefore, in the present invention, the cutting unit and the laminating unit are arranged on the same processing line, thereby enabling the electrode tab formation process and the laminating process to be performed continuously.

[0067] Therefore, the facility space required for manufacturing the electrode assembly can be reduced. In addition, since the time required to transport the electrode roll is not required, the time required to manufacture the electrode assembly can be shortened, and the cutting process and the lamination process can be automated.

[0068] For example, if the scoring and laminating processes are performed continuously on the same processing line, the time reduction may be approximately 5% to 50% of the time required when the scoring and laminating processes are performed discontinuously.

[0069] In a specific example, the inspection member 215 is attached to Figure 2 In the ultrasonic cutter 210, the inspection member 215 faces in a direction parallel to the cutting edge 211. A visual camera can be used as the inspection member 215.

[0070] Conventional pressure cutters are difficult to install inspection components on due to the impact of the cutting process. However, the present invention proposes a structure in which an inspection component is attached to the ultrasonic cutter. This allows the proper shape of the electrode tabs to be determined while the electrode plate is being cut. This shortens the manufacturing process of the electrode assembly, thereby improving productivity.

[0071] Figure 1 The electrode plate supply unit 100 includes a positive electrode plate supply unit for supplying positive electrode plates 110 and a negative electrode plate supply unit for supplying negative electrode plates 120 .

[0072] The positive electrode plate 110 is provided with a positive electrode mixture coating portion 111 on the opposite surface of the positive electrode plate foil 113, and a positive electrode mixture non-coating portion 112 on the opposite surface of the positive electrode plate foil 113, on which the positive electrode mixture is not formed by coating. In other words, the positive electrode mixture non-coating portion 112 is an exposed portion of the positive electrode plate foil 113.

[0073] The description of the positive electrode plate 110 having the positive electrode mixture coating portion 111 and the positive electrode mixture non-coating portion 112 not formed by the coating process to form a positive electrode mixture also applies to the negative electrode plate 120 having the negative electrode mixture coating portion 121 and the negative electrode mixture non-coating portion 122 not formed by the coating process to form a negative electrode mixture.

[0074] refer to Figure 1 and 2 , Figure 2 The cutting line 216 of the cutting blade 211 of the ultrasonic cutter 210 is formed to correspond to the outer periphery of the unit electrode in the direction in which the electrode tabs are formed.

[0075] Thus, when the cutting blade 211 of the ultrasonic cutter is set at the position where the electrode tab is to be formed and the ultrasonic cutter is used to punch the electrode plate, the remaining portion of the positive electrode mixture non-coated portion 112 except the positive electrode tab 114 is cut along the shape of the cutting line 216, thereby forming the positive electrode tab 114, and the remaining portion of the negative electrode mixture non-coated portion 122 except the negative electrode tab 124 is cut along the shape of the cutting line 216, thereby forming the negative electrode tab 124.

[0076] An electrode forming unit 400 is provided at the rear of the cutting unit 200. The electrode forming unit 400 is used to cut the positive electrode sheets having the positive electrode tabs 114 formed thereon to produce the positive electrodes, and to cut the negative electrode sheets having the negative electrode tabs 124 formed thereon to produce the negative electrodes. In other words, the electrode forming unit 400 is provided between the cutting unit 200 and the laminating unit 300.

[0077] The unit positive electrode and the unit negative electrode refer to a single positive electrode and a single negative electrode manufactured by cutting the positive electrode plate and the negative electrode plate at predetermined intervals. In this specification, the positive electrode includes the meaning of the unit positive electrode, and the negative electrode includes the meaning of the unit negative electrode.

[0078] In the electrode forming unit 400 , the cutter 410 for cutting the electrode plate may be a pressure cutter including an upper cutter and a lower cutter, or an ultrasonic cutter may be used.

[0079] If an ultrasonic cutter is used, the electrode plate can be cut to minimize damage to the electrode mix layer and the electrode plate foil.

[0080] The unit positive electrode and the unit negative electrode cut by the electrode forming unit are transferred to the laminating unit 300 in a state where they are attached to the separator 150 and spaced a predetermined distance apart from each other. The positive electrode 131 attached to the separator 150 and the negative electrode 132 attached to the separator 150 are laminated to each other while passing between a pair of rollers 310 included in the laminating unit 300. Subsequently, a separator cutting process is performed, thereby manufacturing a single cell having a structure in which a positive electrode, a separator, a negative electrode, and a separator are stacked in this order.

[0081] In a specific example, the electrode assembly manufacturing method according to the present invention may include: (a) a step of conveying an electrode plate to a cutting unit, (b) a step of forming an electrode tab using an ultrasonic cutter, (c) a step of cutting the electrode plate into unit electrodes, and (d) a step of laminating the positive electrode and the negative electrode with each other in a state where a separator is inserted between the positive electrode and the negative electrode, wherein steps (a) to (d) can be performed on a continuous processing line.

[0082] like Figure 1 As shown, step (b) performed on the cutting unit 200 and step (c) performed on the electrode forming unit 400 can be performed sequentially. In step (b), the ultrasonic cutter 210 can be used as the first ultrasonic cutter. In step (c), the cutter 410 can be used as the second ultrasonic cutter.

[0083] The ultrasonic cutter 210 vibrates in a direction perpendicular to the positive electrode plate 110 and the negative electrode plate 120. Therefore, the ultrasonic cutter 210 moves in a direction perpendicular to the positive electrode plate and the negative electrode plate so that the moving direction of the ultrasonic cutter is consistent with the vibration direction of the ultrasonic cutter.

[0084] Related to this, Figure 3 This is an enlarged view of the cutting edge of the ultrasonic cutter.

[0085] refer to Figure 3 , the cutting line 216 of the cutting blade 211 of the ultrasonic cutter is bent to correspond in shape to the outer periphery of the unit electrode formed with the electrode tab.

[0086] Referring to the enlarged cross-sectional view of the cutting blade taken along line A-A', the end of the cross-section of the cutting blade is formed into a V-shape. Therefore, the cutting blade must move in a state perpendicular to the electrode plate to cut the electrode plate by the end of the cutting blade. In this case, the contact between the cutting blade and the electrode plate can be minimized, thereby minimizing the friction between them. If the cutting blade moves in a state inclined relative to the electrode plate instead of perpendicular to the electrode plate to cut the electrode plate, then the electrode plate may be burned due to the friction generated by the contact between the V-shaped inclined surface of the end of the cutting blade and the electrode plate.

[0087] At the same time, the cutting line of the cutting edge of the ultrasonic cutter is formed in a uniform plane. That is, the length of the cutting edge in the y-axis direction is uniform as a whole.

[0088] Related to this, Figure 4 are plan views showing different shapes of cutting edges.

[0089] refer to Figure 4From (a) to (c), the length of the cutting edge in the y-axis direction is uneven. That is, the cutting lines 236, 246 and 256 of the cutting edge are not formed in a uniform plane.

[0090] If the electrode plate is cut using a conventional pressure cutter comprising an upper cutter and a lower cutter, a cutting blade having any of the above shapes will be used to increase the cutting force. Figure 4 When the cutting edge shown in (a) to (c) is used to cut the electrode plate, the cutting edge must be further moved h1, h2 and h3 in the y-axis direction.

[0091] In contrast, Figure 4 Compared with the cutting blade shown in FIG. 1 , the moving distances of the cutting blade used in the present invention in the y-axis direction are reduced by h1, h2, and h3, thereby reducing the time required to form the electrode tab compared with the case of using a conventional pressure cutter.

[0092] Figure 5 is a partially enlarged view showing a portion of the positive electrode plate where a positive electrode tab is formed.

[0093] refer to Figure 5 The positive electrode plate is cut to form an outer periphery 115 of the positive electrode at a portion offset G toward the positive electrode mixture coating portion 111 based on a boundary line 116 between the positive electrode mixture coating portion 111 and the positive electrode mixture non-coating portion 112 .

[0094] That is, the ultrasonic cutter cuts not only the positive electrode mixture non-coated portion 112 where the positive electrode tab 114 is formed, but also the positive electrode mixture coated portion 111 .

[0095] Figure 6 is a perspective view of a portion of an electrode assembly manufacturing apparatus according to a second embodiment.

[0096] refer to Figure 6 The positive electrode plate 110 supplied from the electrode plate supply part 100 is equipped with a positive electrode mixture coating part 111 and a positive electrode mixture non-coating part 112, and a positive electrode tab 114 is formed in the positive electrode mixture non-coating part 112 and at the boundary between the positive electrode mixture coating part 111 and the positive electrode mixture non-coating part 112.

[0097] and Figure 1 Differently, the two cutting edges 211 of the ultrasonic cutter 210 are provided continuously. The speed of forming the positive electrode tab can be increased in proportion to the extension of the cutting edge 211.

[0098] Figure 7is a perspective view of a portion of an electrode assembly manufacturing apparatus according to a third embodiment.

[0099] refer to Figure 7 ,and Figure 1 In contrast, the ultrasonic cutter further includes an auxiliary cutting edge 219. The auxiliary cutting edge 219 is used to form a recess for guiding the cutting of the unit electrode. The recess can be formed to indicate the position of cutting the electrode plate to produce the unit electrode.

[0100] The recess may be formed in a slit shape or a shape in which the recess size gradually increases from the inner side to the outer side of the electrode plate, but the shape of the recess is not particularly limited. Specifically, a V-shaped recess may be formed.

[0101] Therefore, a cutting process of forming the electrode tab and a cutting process of forming the recess for guiding the cutting of the unit electrode can be performed simultaneously, whereby the manufacturing process can be shortened.

[0102] Figure 8 is a perspective view showing a cutting blade of an electrode assembly manufacturing apparatus according to a fourth embodiment.

[0103] refer to Figure 8 , the cutting line 266 of the cutting blade 231 is formed in a shape corresponding to the outer periphery of the positive electrode 131 .

[0104] In use Figure 8 When the cutting blade is used, the steps of forming the electrode tabs using the ultrasonic cutter and cutting the electrode plate into unit electrodes can be performed simultaneously. Therefore, the positive electrode 131 formed with the positive electrode tabs can be separated from the positive electrode plate by punching the electrode plate once. In this case, there is no need to Figure 1 The electrodes form a unit.

[0105] Therefore, the manufacturing process of the electrode assembly can be simplified and the manufacturing time can be shortened.

[0106] In order to determine whether the electrode plate is damaged when using the electrode assembly manufacturing apparatus according to the present invention, electrodes obtained by cutting the electrode plate using an ultrasonic cutter and electrodes obtained by cutting the electrode plate using a pressure cutter are compared below.

[0107] Figure 9 This is an enlarged view of the cut section of the electrode plate cut using a pressure cutter. Figure 10 This is a plan view of an electrode plate cut using a pressure cutter. Figure 11 This is an enlarged view of the cut section of the electrode plate cut using an ultrasonic cutter. Figure 12 This is a plan view of an electrode plate cut using an ultrasonic cutter.

[0108] refer to Figure 9 and10 ,from Figure 9 As can be seen from the cut section of the electrode plate cut using a pressure cutter, the electrode plate foil 511 is bent and the electrode mixture layer 512 is separated from the electrode plate foil 511. Figure 10 As can be seen from the portion indicated by the dotted line in FIG, the electrode mixture layer 512 is separated from the electrode plate foil 511 .

[0109] Reference using ultrasonic cutter Figure 11 and 12 , it can be seen that the electrode plate foil 611 and the electrode mixture layer 612 are not deformed in the cut section of the electrode plate, and the electrode mixture layer 612 is normally attached to the electrode plate foil 611 .

[0110] Figure 13 1 is a diagram showing a comparison of cross sections of a positive electrode plate having an insulating coating cut using a pressure cutter and an ultrasonic cutter.

[0111] refer to Figure 13 , it can be seen that the insulating coating is separated from the positive electrode cut using pressure, as indicated by the dotted circle. However, it can be seen that the positive electrode cut using an ultrasonic cutter has a neat appearance with no separation of the insulating coating, and the boundary line of the positive electrode mixture layer remains smooth, that is, the positive electrode mixture layer is stably attached to the positive electrode plate foil.

[0112] Figure 14 FIG. 1 is a diagram showing a comparison of cross sections of negative electrode plates cut using pressure, an ultrasonic cutter, and a laser.

[0113] refer to Figure 14 , it can be seen that when pressure cutting is performed, the electrode plate bends, and burrs are generated on the electrode plate foil 711 in the cut section of the positive electrode plate. It can be seen that when laser cutting is performed, the electrode mixture layer 712 undergoes thermal deformation due to the heat from the laser in the cross-section of the electrode tab and the cut section. It can be seen that when cutting is performed using an ultrasonic cutter, neither the electrode plate foil 711 nor the electrode mixture layer 712 is damaged in the electrode tab and the cut section. The electrode plate foil 711 does not even bend in the cut section, and the electrode mixture layer 712 is normally attached to the electrode plate foil 711.

[0114] In the case of using the ultrasonic cutter as described above, the electrode mixture layer can be kept stably attached to the electrode plate foil, and burr generation on the cut section of the electrode plate foil and deformation of the cut section of the electrode plate foil can be minimized.

[0115] Those skilled in the art to which the present invention pertains will appreciate that, based on the above description, various applications and modifications are possible within the scope of the present invention.

[0116] (Description of reference numbers)

[0117] 10: Electrode assembly manufacturing equipment

[0118] 100: Electrode plate supply unit

[0119] 110: Positive electrode plate

[0120] 111: Positive electrode mixture coating part

[0121] 112: Positive electrode mixture non-coating part

[0122] 113: Positive electrode foil

[0123] 114: Positive electrode tab

[0124] 115: Outer periphery of positive electrode

[0125] 116: Boundary Line

[0126] 120: Negative electrode plate

[0127] 121: Negative electrode mixture coating part

[0128] 122: Negative electrode mixture non-coating part

[0129] 124: Negative electrode tab

[0130] 131: Positive electrode

[0131] 132: Negative electrode

[0132] 150: Partition

[0133] 200: Cutting unit

[0134] 210: Ultrasonic cutter

[0135] 211, 231: cutting edge

[0136] 212: Oscillator

[0137] 213: Amplifier

[0138] 214: welding head

[0139] 215: Check components

[0140] 216, 236, 246, 256, 266: cutting lines

[0141] 219: Auxiliary cutting edge

[0142] 220: Mold

[0143] 300: Lamination unit

[0144] 310: Roller

[0145] 400: Electrode forming unit

[0146] 410: Cutter

[0147] 511, 611, 711: electrode plate foil

[0148] 512, 612, 712: electrode mixture layer

[0149] Industrial Applicability

[0150] As is clear from the above description, in the present invention, an ultrasonic cutter is used to form the electrode tab, thereby preventing deformation of the electrode plate foil or separation of the electrode mixture layer in the cut sections of the electrode mixture coated portion and the electrode mixture non-coated portion.

[0151] Furthermore, the cutting unit and the laminating unit for forming the electrode tabs are provided on the same processing line, whereby continuous processing can be performed, thereby making it possible to reduce the space required for the electrode assembly manufacturing facility.

[0152] Also, in the case where the inspection member is coupled to the ultrasonic cutter, the cut cross-section of the electrode plate on which the electrode tab is formed can be inspected while the electrode tab is being formed.

Claims

1. An electrode assembly manufacturing device, comprising: an electrode plate supply unit for supplying an electrode plate having an electrode mixture coating portion and an electrode mixture non-coating portion; a cutting unit provided at the rear of the electrode plate supply unit, for forming electrode tabs on the electrode plates; as well as The laminating unit provided at the rear of the electrode plate supply unit is used to laminate the stacked positive and negative electrodes in a state where a separator is interposed between the positive and negative electrodes, wherein The cutting unit includes a mold for supporting the electrode plate and an ultrasonic cutter provided separately from the mold, wherein the ultrasonic cutter is used to form the electrode tabs. The cutting line of the cutting blade of the ultrasonic cutter is formed to correspond to the outer periphery of the unit electrode in the direction in which the electrode tab is formed. The cutting unit and the laminating unit are provided on the same processing line to perform continuous processing, The ultrasonic cutter further includes an auxiliary cutting edge for forming a recess on an edge of the electrode plate, the recess being used to guide cutting of the unit electrode. 2 . The electrode assembly manufacturing apparatus according to claim 1 , further comprising an electrode forming unit provided between the cutting unit and the laminating unit, the electrode forming unit being configured to cut the electrode plate to manufacture the unit electrodes. 3 . The electrode assembly manufacturing apparatus according to claim 1 , wherein the ultrasonic cutter cuts the electrode mixture coated portion. 4 . The electrode assembly manufacturing apparatus according to claim 1 , wherein a cutting line of the cutting edge of the ultrasonic cutter is formed in a uniform plane. The electrode assembly manufacturing apparatus according to claim 1 , wherein the ultrasonic cutter is coupled with an inspection member.

6. A method for manufacturing an electrode assembly using the electrode assembly manufacturing apparatus according to any one of claims 1 to 5, the method comprising: (a) transferring the electrode plate to the cutting unit; (b) forming electrode tabs and recesses using the ultrasonic cutter; (c) cutting the electrode plate into unit electrodes according to the positions indicated by the recesses; and (d) laminating the positive electrode and the negative electrode with each other in a state where a separator is interposed between the positive electrode and the negative electrode, wherein Steps (a) to (d) are performed on a continuous processing line.

7. The method for manufacturing an electrode assembly according to claim 6, wherein: Step (b) and step (c) are performed sequentially, Step (b) is performed using a first ultrasonic cutter, Step (c) is performed using a second ultrasonic cutter. 8 . The method for manufacturing an electrode assembly according to claim 6 , wherein a vibration direction of the ultrasonic cutter is a direction perpendicular to the electrode plate.

9. The electrode assembly manufacturing method according to claim 6, wherein step (b) is performed by the following processing: while the cutting edge of the ultrasonic cutter is placed on the outer surface of the electrode plate, the cutting edge of the ultrasonic cutter is pushed once to form the outer periphery of the unit electrode in the direction of forming the electrode tab.

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