Pick-and-place device and secondary battery manufacturing device comprising same

Abstract

The present invention relates to an electrode assembly inspection apparatus and, more specifically, to: an inspection apparatus for inspecting damage to the outermost separator of an electrode assembly; and a secondary battery manufacturing apparatus and manufacturing method for applying same to an in-line process. According to one embodiment of the present invention, a secondary battery lead welding device can be provided, the device comprising: a welding machine for welding a plurality of electrode tabs of an electrode assembly to an electrode lead; an unloading device, which receives the welded electrode assembly from the welding machine so as to transfer same for a subsequent process; a pick-and-place device including a picker that supports the bottom surface of the electrode assembly welded in the welding machine so as to transfer same to the unloading device; and an upper end sensing device for sensing whether the uppermost separator of the electrode assembly is damaged by the picker.

Description

Pick-and-place device and secondary battery manufacturing device including the same

[0001] The present invention relates to an electrode assembly inspection device, and more specifically, to a pick-and-place device having a function of inspecting damage to the outermost separator of an electrode assembly, and a secondary battery manufacturing device and manufacturing method applying the same to an inline process.

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0181385, filed December 14, 2023, and Korean Patent Application No. 10-2024-0184366, filed December 12, 2024, the entire contents of which are incorporated herein by reference.

[0003] With the proliferation of portable, small-sized electronic devices, the development of new types of secondary batteries, such as nickel-metal hydride batteries and lithium secondary batteries, is rapidly progressing. Recently, lithium secondary batteries are being widely used not only in power tools but also in automobiles.

[0004] A lithium secondary battery is a battery that uses carbon such as graphite as an anode active material, an oxide containing lithium as an anode material, and a non-aqueous solvent as an electrolyte.

[0005] These secondary batteries are manufactured in the form of a battery assembly, with the electrode assembly, in which the positive electrode, separator, and negative electrode are sequentially measured, housed in an outer packaging such as a pouch or cylindrical can. Subsequently, an electrolyte is injected into the battery assembly using an electrolyte injection device.

[0006] There are many different methods for stacking electrode assemblies. Representative examples include jelly-roll electrode assemblies, which are formed by rolling up long sheet-shaped anodes and cathodes with a separator interposed therebetween; stacked electrode assemblies, in which a plurality of anodes, a plurality of separators, and a plurality of cathodes cut into units of a predetermined size are sequentially stacked; and stacked / folded electrode assemblies, in which unit anodes or cathodes are stacked on a long sheet-shaped separator and then the separator is repeatedly folded.

[0007] A stacked electrode assembly may be formed by repeatedly stacking a unit anode, a unit separator, and a unit cathode multiple times, or may be formed by stacking a unit cell shape and then stacking a plurality of unit cells. In this case, a unit cell refers to a shape in which a unit separator and a unit anode or unit cathode are stacked, and may also be referred to as a semi-finished product.

[0008] For example, a unit cell in which a unit separator, a unit anode, a unit separator, and a unit cathode are laminated may be called a mono-cell, and a unit cell in which a unit separator, a unit anode, and a unit separator are laminated may be called a half-cell. Of course, the stacking order of the anode and cathode in the mono-cell may be changed, and a cathode may be laminated instead of an anode in the half-cell. First, a mono-cell and a half-cell may be manufactured, and then multiple mono-cells may be laminated, and finally, a half-cell may be laminated to manufacture an electrode assembly.

[0009] When a plurality of unit cells are stacked after manufacturing such a unit cell, there is an advantage in that sufficient adhesive strength can be provided between the separator and the anode and between the separator and the cathode, and there is an advantage in that stacking efficiency and stacking reliability can be improved.

[0010] While there are various methods for manufacturing electrode assemblies by laminating them, the uppermost and lowermost surfaces of the electrode assembly are formed by separators. These separators are referred to as the uppermost and lowermost separators, and are collectively referred to as the outermost separator.

[0011] Figure 1(a) is a plan view of the electrode assembly, and Figure 1(b) can be said to be a front view of the electrode assembly.

[0012] As illustrated, the electrode assembly (10) is manufactured so that a plurality of positive electrodes (4), separators (3), and negative electrodes (5) are sequentially stacked, and the separators (3) are positioned on the uppermost and lowermost surfaces. In addition, the electrode assembly (10) in the shape of a square may be provided with a positive electrode lead (1) on one short side and a negative electrode lead (2) on the other side. Of course, it may also be manufactured so that both the positive electrode lead (1) and the negative electrode lead (2) are provided on one short side.

[0013] An electrode assembly formed by sequentially stacking electrodes and separators can be called a stack-type electrode assembly, and can be distinguished from a jelly-roll type electrode assembly.

[0014] Electrode tabs protruding from the anode are provided, and these electrode tabs are pre-welded to electrically connect to each other. The pre-welded electrode tabs are then welded to a lead to form the anode lead. The cathode lead is also formed in the same manner.

[0015] The outer surface of the electrode assembly (10) can be wrapped with tape (6) to secure the laminated positive electrode, negative electrode, and separator. This electrode assembly (10) can be later inserted into a case such as a pouch together with an electrolyte, and the manufacture of a secondary battery can be completed through an activation process.

[0016] During the manufacturing process of the electrode assembly (10), damage to the outermost separator may occur. For example, the separator may tear or lift, or even fold. Previously, damage to the outermost separator was resolved through visual inspection of a sample, resulting in reduced reliability.

[0017] Damage to the outermost separator may occur at the long side and corner portions of the electrode assembly (10), and may occur during various processes such as the transport process or taping process.

[0018] Prior art (KR 2022-0077252A) discloses a separator damage inspection device. According to the prior art, the inspection device detects separator damage at a pre-manufacturing stage of an electrode assembly, for example, at the monocell and half-cell stages.

[0019] Prior art requires separate electrical and pressure plates, making it suitable for sample inspection but difficult to apply to automated electrode assembly manufacturing processes. Furthermore, while suitable for inspecting separator damage in monocells and half-cells, it presents a challenge in inspecting the outermost separator for damage in electrode assemblies manufactured by stacking monocells and half-cells.

[0020] In particular, according to the prior art, there is a problem in that it is difficult to inspect for damage to the outermost separator for the entire electrode assembly being manufactured.

[0021] Through one embodiment of the present invention, an apparatus and method capable of effectively detecting damage to a separator of an electrode assembly are provided.

[0022] Through one embodiment of the present invention, it is intended to provide a pick-and-place device capable of detecting damage to a separator of an electrode assembly.

[0023] Through one embodiment of the present invention, it is intended to provide a shuttle device capable of detecting damage to a separator of an electrode assembly.

[0024] Through one embodiment of the present invention, it is intended to provide a device and method capable of effectively performing the uppermost and lowermost separators of an electrode assembly in the final process of actually manufacturing the electrode assembly.

[0025] Through one embodiment of the present invention, it is intended to provide a lead welding device capable of performing damage to a separator of an electrode assembly in an inline process.

[0026] Through one embodiment of the present invention, it is intended to provide a method for manufacturing an electrode assembly, which can perform an inline process to check for damage to the uppermost and lowermost separators of the electrode assembly.

[0027] Through one embodiment of the present invention, it is intended to provide a device and method capable of effectively detecting damage to the uppermost and lowermost separators through a device and process for transferring an electrode assembly to an unloading machine after lead welding and a device and process for performing a transfer buffer for the electrode assembly in the unloading machine.

[0028] To achieve the aforementioned purpose, according to one embodiment of the present invention, a pick-and-place device having a function of inspecting damage to a separator of an electrode assembly can be provided. In particular, a pick-and-place device including an upper inspection device for inspecting damage to the uppermost separator of an electrode assembly can be provided.

[0029] The above pick-and-place device may include a picker that supports the lower surface of the electrode assembly and moves the electrode assembly through three-axis movement.

[0030] The picker may be equipped with a detection device that detects damage to the separator of the electrode assembly. Of course, the entire configuration or a portion of the detection device may be provided in the picker or the pick-and-place device. The detection device may operate in conjunction with the operation of the picker. Accordingly, the pick-and-place device may be implemented including the detection device.

[0031] The above detection device may include a current-carrying plate that is provided to move integrally with the picker and moves up and down with respect to the picker so as to selectively come into contact with the upper surface of the electrode assembly; a probe that is provided to move integrally with the picker and moves up and down with respect to the picker so as to selectively come into contact with the electrode leads of the electrode assembly; and a detector that applies current to the probe and detects whether the separator of the electrode assembly is damaged based on whether or not the current is detected through the current-carrying plate.

[0032] The above detection device can specifically detect damage to the upper separator of the electrode assembly. Therefore, it can be referred to as an upper detection device.

[0033] The above pick-and-place device may be provided between a welding machine that welds multiple electrode tabs of an electrode assembly to electrode leads and an unloading machine that moves the electrode assembly after welding for subsequent processing. The picker may move three-axis between the welding machine and the unloading machine to transport the electrode assembly from one point to two points. Of course, the pick-and-place device may be a part of the welding machine or a part of the unloading machine.

[0034] The above pick-and-place device may be provided to separate and move the electrode assembly from a pallet on which the electrode assembly is mounted and moved.

[0035] The above welding device may be configured to sequentially weld the positive electrode lead and the negative electrode lead to the electrode assembly mounted on the pallet as the electrode assembly moves through a linear motion system. The first electrode lead may be referred to as the positive electrode lead, and the second electrode lead may be referred to as the negative electrode lead, or vice versa.

[0036] For welding electrode leads, pre-welding may first be performed to connect multiple electrode tabs to each other, and then electrode leads may be welded to the multiple pre-welded electrode tabs. Accordingly, the welding machine may be sequentially equipped with a first electrode pre-welding stage, a first electrode welding stage, a second electrode pre-welding stage, and a second electrode welding stage.

[0037] Electrode lead welding can be completed as one electrode assembly passes through multiple stages via the linear motion system.

[0038] The above pick-and-place device may be configured to separate and move the electrode assembly from the pallet located at the transfer position after the welding is completed. That is, when the welding is completed and the pallet is moved to the transfer position, the electrode assembly at the transfer position is moved. The transfer position may be referred to as a first point.

[0039] The above picker includes a lower picker that supports the lower surface of the electrode assembly and an upper picker provided above the lower picker, and the conductive plate may be provided so as to be able to be lifted between the lower picker and the upper picker. The upper picker itself may also be lifted.

[0040] The above picker may include a cylinder configured to elevate the conductive plate relative to the upper picker. Of course, the picker may include a cylinder configured to elevate the conductive plate together with the upper picker relative to the lower picker.

[0041] One end of the cylinder may be connected to the upper picker, and the other end may be connected to the conductive plate. Accordingly, when the cylinder is driven, the conductive plate may move downward as the overall length of the cylinder increases.

[0042] The above picker may include a connecting picker connecting the upper picker and the lower picker, and the connecting picker may be provided with a cylinder for raising and lowering the energizing plate.

[0043] In order to achieve the above-described object, according to one embodiment of the present invention, a shuttle device for supporting a lower surface of an electrode assembly and transporting the electrode assembly through a reciprocating motion may be provided, the shuttle device comprising: a buffer plate provided to support and transport the electrode assembly; a current-conducting plate provided on an upper surface of the buffer plate and provided to be in close contact with the lower surface of the seated electrode assembly; a probe that moves up and down to selectively contact an electrode lead of the electrode assembly; and a detector that applies current to the probe and detects whether a separator of the electrode assembly is damaged based on whether or not current is detected through the current-conducting plate.

[0044] A detection device capable of detecting damage to the lowermost separator of an electrode assembly can be implemented using the above shuttle device. The shuttle device may include a detection device, and the operation of the detection device may be performed in conjunction with the operation of the shuttle device.

[0045] The above shuttle device may be provided in an unloading device that moves the electrode assembly, for which welding is completed, from a welding device that welds multiple electrode tabs of the electrode assembly to electrode leads for subsequent processing.

[0046] It is preferable that the above shuttle device or detection device includes a cylinder provided to elevate the probe.

[0047] In order to achieve the above-described object, according to one embodiment of the present invention, a secondary battery lead welding device may be provided, including: a welding machine for welding a plurality of electrode tabs of an electrode assembly with electrode leads; an unloading machine for receiving an electrode assembly, on which welding has been completed, from the welding machine and transporting it for a subsequent process; a pick-and-place device including a picker for supporting a lower surface of the electrode assembly, on which welding has been completed, in the welding machine and transporting it to the unloading machine; and an upper detection device for detecting whether a separator at the top of the electrode assembly is damaged through the picker.

[0048] In order to achieve the above-described object, according to one embodiment of the present invention, a secondary battery lead welding device may be provided, including a welding machine that welds a plurality of electrode tabs of the electrode assembly to electrode leads while sequentially moving the electrode assembly through a linear motion system; an unloading machine that receives the electrode assembly, on which welding has been completed, from the welding machine and transfers it for a subsequent process; a pick-and-place device that includes a picker that supports the lower surface of the electrode assembly, on which welding has been completed in the welding machine, and transfers the electrode assembly to the unloading machine through three-axis movement; and an upper detection device that detects whether the uppermost separator of the electrode assembly is damaged.

[0049] The above upper detection device may be a part of the above pick-and-place device.

[0050] The above upper detection device may include a current-carrying plate provided on the picker and selectively brought into close contact with the upper surface of the electrode assembly, a probe selectively contacting the electrode lead of the electrode assembly, and a detector that applies current to the probe and detects whether the uppermost separator of the electrode assembly is damaged based on whether current is detected through the current-carrying plate.

[0051] The above pick-and-place device may be provided between the welding machine and the unloading machine. Of course, the pick-and-place device may be a part of the welding machine or the unloading machine.

[0052] The above pick-and-place device may be provided to separate and move the electrode assembly from a pallet on which the electrode assembly is mounted and moved.

[0053] It is preferable that the above welding machine be equipped to sequentially perform pre-welding of the first electrode tab, welding of the first electrode lead, pre-welding of the second electrode tab, and welding of the second electrode lead as the electrode assembly mounted on the pallet moves through the linear motion system.

[0054] It is preferable that the above pick-and-place device be provided to separate and move the electrode assembly from the pallet located at the transfer position (first point) of the welding machine after the welding is completed.

[0055] The above picker includes a lower picker that supports the lower surface of the electrode assembly and an upper picker provided on the upper portion of the lower picker, and the conductive plate can be provided so as to be liftable between the lower picker and the upper picker.

[0056] The above picker may include a cylinder provided to elevate the energizing plate relative to the upper picker.

[0057] It is preferable that one end of the above cylinder is connected to the upper picker and the other end is connected to the energizing plate.

[0058] The above-described upper detection device can perform an inspection after lowering the energizing plate and probe before the picker moves to the first position and makes contact with the lower surface of the electrode assembly, i.e., while the electrode assembly is still seated on the pallet. After the inspection is completed, the entire picker can be raised, thereby separating the electrode assembly from the pallet.

[0059] The above-mentioned upper detection device can perform inspection while the picker is separating the electrode assembly from the pallet at the first point and transporting it to the second point. This is because the conductive plate and probe can be lowered relatively toward the electrode assembly, which is relatively fixed to the picker, while the entire picker is moving.

[0060] The above unloading device may include a shuttle device that transports the electrode assembly through reciprocating movement of a buffer plate that supports the lower surface of the electrode assembly.

[0061] A bottom inspection device that detects damage to the lowest separator of the electrode assembly can be implemented through the above shuttle device.

[0062] The above lower inspection device may include a current-carrying plate provided on the upper surface of the buffer plate to be in close contact with the lower surface of the electrode assembly installed thereon; a probe selectively contacting the electrode lead of the electrode assembly; and a detector that applies current to the probe and detects whether the lowermost separator of the electrode assembly is damaged based on whether or not the current is detected through the current-carrying plate.

[0063] In order to achieve the above-described object, according to one embodiment of the present invention, a secondary battery lead welding device may be provided, including a welding machine that welds a plurality of electrode tabs of the electrode assembly to electrode leads while sequentially moving the electrode assembly through a linear motion system; an unloading machine that receives the electrode assembly, on which welding has been completed, from the welding machine and transfers it for a subsequent process; a pick-and-place device that includes a picker that supports the lower surface of the electrode assembly, on which welding has been completed in the welding machine, and transfers the electrode assembly to the unloading machine through three-axis movement; and an upper detection device that detects whether the uppermost separator of the electrode assembly is damaged.

[0064] According to the present embodiment, a welding device for welding a lead of an electrode assembly may include a welding machine in which the lead of the electrode assembly is welded along a plurality of welding stages, and an unloading machine in which the electrode assembly, after welding, is transported from the welding machine.

[0065] Welding in the welding machine, transport to the unloading machine, and transport and buffering for subsequent processing can all be performed automatically. This can be done in-line. During this process, damage to the top and bottom separators of the electrode assembly can also be automatically checked. In particular, the use of a pick-and-place device and a shuttle device eliminates the need for independent, additional processes or inspection equipment, enabling a highly efficient electrode assembly manufacturing process.

[0066] In order to achieve the above-described purpose, according to one embodiment of the present invention, a control method for a welding device including a welding device for welding a lead to an electrode tab of an electrode assembly and an unloading device for moving the electrode assembly, after welding, to a subsequent process can be provided.

[0067] The above control method may include a welding process for welding a lead to an electrode tab while sequentially moving the electrode assembly in a welding stage, a pick-up process for transferring the electrode assembly, after the welding process has been completed, to a shuttle device of an unloading machine using a pick-and-place device, and a shuttle process for transferring the electrode assembly using the shuttle device.

[0068] In the above pickup process, it is preferable that an upper inspection process be performed using the pick-and-place device to check for damage to the uppermost separator of the electrode assembly. To perform the upper inspection process, it is preferable that a conductive plate that comes into contact with the upper surface of the electrode assembly is provided on the picker of the pick-and-place device.

[0069] In the above shuttle process, it is preferable that a lower inspection process be performed using the shuttle device to check for damage to the lowermost separator of the electrode assembly. In order to perform the lower inspection process, it is preferable that a conductive plate that comes into contact with the lower surface of the electrode assembly be provided on the shuttle device.

[0070] The above welding, pick-up, and shuttle processes are performed continuously and inline. That is, in an inline process in which the welding, pick-up, and shuttle processes are performed continuously and sequentially, the upper inspection process and the lower inspection process can be performed simultaneously.

[0071] Through one embodiment of the present invention, a device and method capable of effectively detecting damage to a separator of an electrode assembly can be provided.

[0072] According to one embodiment of the present invention, a pick-and-place device capable of detecting damage to a separator of an electrode assembly can be provided. In particular, a pick-and-place device with an added inspection function for inspecting damage to the uppermost separator of an electrode assembly can be provided.

[0073] According to one embodiment of the present invention, a shuttle device capable of detecting damage to a separator of an electrode assembly can be provided. In particular, a shuttle device with an added inspection function for inspecting damage to the lowermost separator of an electrode assembly can be provided.

[0074] Through one embodiment of the present invention, it is possible to provide a device and method capable of effectively performing the uppermost and lowermost separators of an electrode assembly in the final process of manufacturing the electrode assembly.

[0075] Through one embodiment of the present invention, a lead welding device capable of performing damage to a separator of an electrode assembly in an inline process can be provided.

[0076] Through one embodiment of the present invention, a method for manufacturing an electrode assembly can be provided, which can perform an inline process to check for damage to the uppermost and lowermost separators of the electrode assembly.

[0077] Through one embodiment of the present invention, a device and method capable of effectively detecting damage to the uppermost and lowermost separators can be provided through a device and process for transferring an electrode assembly to an unloading machine after lead welding and a device and process for performing a transfer buffer for the electrode assembly in the unloading machine.

[0078] Figure 1 is a conceptual diagram of an electrode assembly and a damaged portion of a separator of the electrode assembly.

[0079] Figure 2 is a conceptual diagram of an upper inspection device for inspecting damage to the uppermost separator according to one embodiment of the present invention.

[0080] Figure 3 is a conceptual diagram of a lower inspection device for inspecting damage to the lowermost separator according to one embodiment of the present invention.

[0081] Figure 4 is a layout diagram of a lead welding device according to one embodiment of the present invention.

[0082] Figures 5 and 6 are side and front views of the upper inspection device implemented in the pick-and-place device.

[0083] Figures 7 and 8 are side and front views of the lower inspection device implemented in the shuttle device.

[0084] Figure 9 illustrates an example of a method for manufacturing a secondary battery according to one embodiment of the present invention.

[0085] Hereinafter, with reference to the attached drawings, an electrode assembly inspection device according to an embodiment of the present invention will be described in detail.

[0086] Figure 2 is a conceptual diagram of an inspection device for inspecting damage to the uppermost separator of an electrode assembly, and Figure 3 is a conceptual diagram of an inspection device for inspecting damage to the lowermost separator of an electrode assembly.

[0087] It is preferable that the inspection device according to the present embodiment is a device that inspects an electrode assembly after electrode leads (including positive and negative leads) are formed through welding.

[0088] As shown in Fig. 2, the upper inspection device (100) for determining whether the inspection device, particularly the uppermost separator, is damaged may include a current plate (23), a probe (21, 22), and an inspection device (20).

[0089] The conductive plate (23) is formed of a conductive plate that allows electricity to flow through it, and may be configured to cover the upper surface of the electrode assembly (10). That is, the conductive plate (23) may be provided to uniformly press the entire upper surface of the electrode assembly (10). Therefore, it is preferable that the conductive plate (23) be manufactured to have a larger surface area than the upper surface of the electrode assembly (10).

[0090] Preferably, the conductive plate (23) may include a conductive sponge. For example, a conductive sponge having a predetermined thickness and an area that covers the entire upper surface of the electrode assembly (10) may be provided. The electrode assembly (10) may be inserted into the conductive sponge to a predetermined depth. That is, by pressing the electrode assembly through the conductive plate, the entire uppermost separator of the electrode assembly may be inserted into the conductive sponge. Through this, the entire outermost separator may be uniformly brought into contact with the conductive sponge, thereby enabling a more reliable inspection to be performed.

[0091] The tester (20) can be electrically connected through the above-mentioned conductive plate (23) wire (24).

[0092] The tester (20) can be electrically connected to the probes (21, 22) via wires (25, 26). That is, the tester (20) can be equipped to apply current to the probes (21, 22).

[0093] The probe (21, 22) may be provided to contact leads (1, 2). The leads are electrode leads and may include a positive lead (1) and a negative lead (2).

[0094] Here, the conductive plate (23) and probes (21, 22) may be provided to move up and down for inspection of the outermost separator. For example, after the electrode assembly (10) to be inspected is moved to the inspection position, the conductive plate (23) and probes (21, 22) may be lowered. Through the lowering, the conductive plate (23) comes into surface contact with the uppermost separator, and the probes (21, 22) come into contact with the leads (1, 2).

[0095] Afterwards, current can be applied to the probes (21, 22) in the tester (20) and it can be checked whether current flows to the current-carrying plate (23).

[0096] If the top separator is damaged, the electrodes adjacent to the top separator may be exposed, and if the electrodes are exposed, current may flow along the probes (21, 22), leads (1, 2), and the conductive plate (23). The tester (20) can detect this current to determine whether the top separator is damaged.

[0097] As described above, since the electrode assembly can be manufactured through various lamination methods, the electrode in contact with the uppermost separator can be either an anode or a cathode. For example, in the case of an anode, the cathode probe (22) and the cathode wire (26) can be omitted. For example, in the case of a cathode, the anode probe (21) and the cathode wire (25) can be omitted. However, in the case of a general-purpose inspection device, both an anode probe (21) and a cathode probe (22) may be provided.

[0098] Here, since the positions of the probes (21, 22) and the conductive plate (23) must be different before and after the inspection, a moving device or driving unit that changes the positions is required. For example, the inspection device (100) may further include a lifting device that elevates the probe and the conductive plate.

[0099] According to the present embodiment, the entire inspection device (100) is not provided separately, but can be applied to a portion of the electrode assembly manufacturing process, i.e., an inline manufacturing device. That is, by providing inspection functions to some devices used in the inline manufacturing device, it is possible to implement the inspection device (100) very easily. Such a manufacturing device may be a tap welder for a secondary battery or a lead welding device for a secondary battery. The moving device or driving unit will be described later.

[0100] As shown in Fig. 3, the lower inspection device (200) for determining whether the inspection device, particularly the lowermost separator, is damaged may include a current plate (23), a probe (21, 22), and an inspection device (20).

[0101] The present lower inspection device (200) may be configured in the same manner as the aforementioned upper inspection device (100). However, it may differ in that the conductive plate (23) is provided to cover the lower surface of the electrode assembly (10). Therefore, any duplicate description will be omitted.

[0102] Here, the probes (21, 22) must have different positions before and after inspection. That is, a moving device or driving unit that changes the position of the probe is required. However, in the inspection device (200) according to the present embodiment, the positions of the conductive plate (23) before and after inspection may be the same. Similarly, the entire inspection device (200) may not be provided separately, but may be applied to a part of the manufacturing process of the electrode assembly, i.e., an inline manufacturing device. Such a manufacturing device may be a tap welder for a secondary battery or a lead welding device for a secondary battery. The moving device or driving unit will be described later.

[0103] Fig. 4 illustrates an example of an electrode assembly manufacturing device. More specifically, Fig. 4 illustrates the arrangement of a lead welding device.

[0104] The lead welding device (300) may be defined as a device that gathers multiple electrode tabs of an electrode assembly and welds them to a single electrode lead. The multiple positive electrode tabs are welded to the positive electrode lead, and the multiple negative electrode tabs are welded to the negative electrode lead, thereby completing the manufacture of the electrode assembly. The electrode assembly may then be transferred to a device for subsequent processes, such as a packaging process for combining it with a battery case, such as a pouch, and an electrolyte injection process.

[0105] Electrode assemblies can be manufactured by laminating them using an electrode assembly laminating device prior to the lead welding process. After multiple monocells are laminated in the laminating device, half-cells can be laminated last. Furthermore, the laminating device can perform taping on the outer surface of the electrode assembly. After performing taping and passing an appearance inspection, the electrode assembly can then be input into the lead welding process. In other words, the lamination and stacking process can be performed prior to the lead welding process.

[0106] The electrode assembly (10) whose lamination is completed in the lamination device can be moved to the lead welding device (300). For this purpose, the lead welding device (300) can include a loader (loader, A). The lamination device can include the loader (A). Here, the loader can be referred to as a device that feeds the electrode assembly into the welding device, and can be a part of the lead welding device (300).

[0107] The electrode assembly (10) whose stacking is completed in the stacking device can be moved to the welding device (B) via the loading device (A). In the welding device (B), a welding process in which the positive electrode lead and the negative electrode lead are welded can be performed. The welding device (B) can be said to be the main component of the lead welding device (300). Here, the electrode assembly can be transferred from the loading device (A) to the welding device (B), particularly the positive electrode pre-welding stage (B1), using a pick and place device. That is, the electrode assembly can be moved from the stacking stage to the welding stage via the pick and place (PNP) device.

[0108] The welding process can be performed in multiple sub-processes, and each sub-process can be performed at different stages.

[0109] The sub-processes may include anodic pre-welding, anodic main-welding, cathodic pre-welding, and cathodic main-welding. These sub-processes may be performed through a sub-device or individual stages.

[0110] Here, pre-welding may include a tab guiding process that presses multiple electrode tabs up and down to gather them in the center. After the tab guiding process is complete, welding is performed using ultrasonic fusion to electrically connect and secure the electrode tabs. This process can be referred to as pre-welding.

[0111] Main welding can be defined as a welding process that electrically connects and secures electrode leads to pre-welded electrode tabs. Therefore, a single electrode lead can be electrically connected and secured to multiple electrode tabs.

[0112] In the positive electrode pre-welding stage (B1), the positive electrode tabs of the electrode assembly are pre-welded, and then the electrode assembly can be moved to the main welding stage (B2). In the main welding stage (B2), the positive electrode lead can be welded.

[0113] Thereafter, the negative electrode tabs of the electrode assembly are pre-welded in the negative pre-welding stage (B3), and the electrode assembly can then be moved to the main welding stage (B4). The negative lead can be welded in the main welding stage (B4).

[0114] That is, pre-welding and main welding of the cathode can be performed after pre-welding and main welding of the anode. Of course, pre-welding and main welding of the anode can be performed after pre-welding and main welding of the cathode.

[0115] The electrode assembly (10) can be transported through the above plurality of stages (B1 to B4) through a linear motion system or linear moving system (LMS). The linear motion system includes a plurality of pallets, and the electrode assembly (10) can be placed on the pallets. That is, the electrode assembly (10) is sequentially moved through the stages while positioned on the pallets, and through this, the first electrode lead and the second electrode lead can be sequentially welded, so that the overall welding can be completed.

[0116] The electrode assembly, after the welding process is completed, is transferred to the unloading machine (C) through the pick-and-place device.

[0117] The above winding machine (B) is equipped with a linear motion system, so that multiple pallets move linearly. That is, the electrode assembly placed on the pallet moves linearly sequentially through the linear motion system.

[0118] A linear motion system is a system in which multiple pallets are placed at regular intervals on a circular track, and multiple pallets move and stop simultaneously at regular intervals.

[0119] The electrode assembly can be transferred from the welding machine (B) to the unloading machine (C) using a pick-and-place device. In particular, it can be transferred from the cathode main welding stage (B4) to the unloading machine (C). The electrode assembly (10) is positioned at the transfer position (P, first point) of the welding machine (B) just before being transferred to the unloading machine (C). Here, the transfer position (P) can be said to be a position where the electrode assembly is placed and prepared on a pallet just before being transferred to the unloading machine (C) after the welding process of the electrode assembly is completely completed.

[0120] The unloading device (C) may be equipped with a shuttle (Q, R) device for transporting the electrode assembly. The shuttle device can be said to be a device for transporting the electrode assembly from a specific location to a specific location while moving back and forth.

[0121] First, the shuttle (Q, R) device may include a first shuttle (Q) and a second shuttle (R). The first shuttle (Q) may be configured to seat an electrode assembly transferred from a welding machine (B), and the second shuttle (R) may be configured to seat an electrode assembly transferred from the first shuttle (Q). The second shuttle may be configured to transport a plurality of electrode assemblies as a whole after the plurality of electrode assemblies have been seated.

[0122] Therefore, according to the present embodiment, the loading process, welding process, and unloading process can be performed continuously as a whole. In addition, the lamination process can also be performed continuously. That is, the manufacturing of the electrode assembly can be performed in-line using a pick-and-place device and a linear motion system. Here, according to the present embodiment, the outermost separator of the electrode assembly can be inspected during this in-line process. That is, the inspection can be performed using a device that performs the in-line process.

[0123] Since pick-and-place devices and linear motion systems are commonly used in the secondary battery manufacturing process, their detailed descriptions are omitted.

[0124] Hereinafter, with reference to FIGS. 5 and 6, an inspection device for inspecting the upper separator of an electrode assembly will be described in detail.

[0125] Fig. 5 is a side view of an inspection device that performs inspection using a pick-and-place device, and Fig. 6 is a front view of an inspection device that performs inspection using a pick-and-place device.

[0126] A pick-and-place device for moving an electrode assembly (10) is provided between the welding machine (B) and the unloading machine (C). In particular, the pick-and-place device moves in three axes between the transfer position (P, first point) and the first shuttle (Q, second point). For convenience of explanation, the xy direction is referred to as planar movement and the z direction is referred to as elevation movement.

[0127] The pick-and-place device may include a picker (40) that transports the electrode assembly (10) after placing it thereon. The entire picker (40) moves in a plane and up and down to move the electrode assembly from the transport position (P) to the first shuttle (Q).

[0128] The above picker (40) includes a lower picker (41) that supports and transports the lower surface of the electrode assembly (10) like a lifter of a forklift, and the lower picker (41) may be formed in a fork shape. The lower picker (41) supports the electrode assembly (10) mounted on the pallet (30) as it moves from the lower side to the upper side, thereby causing the electrode assembly (10) to detach from the pallet (30).

[0129] The pallet (30) has an opening (31) so as not to interfere with the rising lower picker (41). A plurality of openings (31) may be provided. That is, as the lower picker (41) rises and the fork-shaped lower picker (41) passes through the opening (31) of the pallet, the electrode assembly (10) can leave the pallet (30) and be placed on the lower picker (41).

[0130] Meanwhile, according to the present embodiment, the picker (40) may include an upper picker (42). The upper picker (42) may be provided above the lower picker (41) with a predetermined space (44) between the lower picker (41). The height of the predetermined space (44) between the upper picker (42) and the lower picker (41) may be fixed. For this purpose, a connecting picker (44) connecting one end of the lower picker (41) and the upper picker (42) may be provided. Accordingly, the cross-sectional shape of the picker (40) may have a channel shape or a “ㄷ” shape.

[0131] As shown, a device for inspecting the uppermost separator of the electrode assembly can be implemented through a picker (40).

[0132] Specifically, an upper inspection device (100) can be provided using the space (44) between the upper picker (42) and the lower picker (41).

[0133] The space (44) above is provided with a conductive plate (23), and the conductive plate (23) can be raised and lowered within the space (44). A probe (21, 22) can be provided to be raised and lowered within the space (44) or outside the space (44).

[0134] A cylinder (28) for elevating the above-mentioned conductive plate (23) and probes (21, 22) may be provided. The cylinder (28) may be provided to elevate the conductive plate (23) and probes (21, 22) together or may be provided to elevate them separately.

[0135] One end of the above cylinder (28) can be fixed to the upper picker (42) and the other end can be connected to the conductive plate (23). When the length of the cylinder (28) increases due to driving of the cylinder, the conductive plate (23) moves downward. Of course, at this time, the probes (21, 22) also move downward.

[0136] Figures 5(a) and 6(a) illustrate the state in which the conductive plate (23) and the probe (21, 22) are in the position before moving downward (original position), and Figures 5(b) and 6(b) illustrate the state in which the conductive plate (23) and the probe (21, 22) are in the position after moving downward (inspection position).

[0137] At the inspection position, the conductive plate (23) is in close contact with the upper surface of the electrode assembly (10), and the probes (21, 22) come into contact with the leads (1, 2) of the electrode assembly (10). At this time, by applying current to the probes (1, 2), it is possible to inspect whether the upper outermost separator is damaged.

[0138] Here, the picker (41) is raised as a whole to move the electrode assembly (10). That is, the electrode assembly (10) is separated from the pallet (30). Therefore, the inspection time through the inspection device (200) may vary.

[0139] For example, as illustrated, an inspection may be performed by moving the conductive plate (23) downward while the electrode assembly (10) is mounted on the pallet (30). At this time, the inspection may be performed after the electrode assembly (10) is pressed in both the upper and lower directions by the pallet (30) and the conductive plate (23). When the inspection is completed, the entire picker (41) may be raised and the electrode assembly (10) may be transported. In this case, it can be seen that the transport is performed after the inspection.

[0140] For example, after the entire picker (41) has been raised and the electrode assembly (10) has been separated from the pallet (30), inspection may be performed during transport of the electrode assembly (10). That is, inspection may be performed by moving the conductive plate (23) downward during transport of the electrode assembly (10). At this time, the electrode assembly (10) may be pressed in both the upper and lower directions by the lower picker (41) and the conductive plate (23) before inspection may be performed. In this case, it can be seen that inspection is performed during transport.

[0141] According to this embodiment, both post-inspection and during-transport inspection are possible. Post-inspection inspection requires separate time for inspection, which can increase process time. This is because both inspection and transport time are required. On the other hand, during-transport inspection does not require separate time for inspection.

[0142] For this reason, it is possible to inspect for damage to the uppermost separator of the electrode assembly very easily using a manufacturing device and manufacturing method using an existing welding machine and PNP.

[0143] Hereinafter, the lower inspection device (200) will be described in more detail with reference to FIGS. 7 and 8. FIG. 7 is a side view of the inspection device (200), and FIG. 8 is a front view of the inspection device (200).

[0144] Figures 7(a) and 8(a) illustrate the state in which the probe (21, 22) is at the position before moving downward (original position), and Figures 7(b) and 6(b) illustrate the state in which the probe (21, 22) is at the position to which it has moved downward (inspection position).

[0145] The shuttle device described above includes a buffer plate (50) on which an electrode assembly is mounted and transported through reciprocating movement. A plurality of buffer plates (50) may be provided, and an electrode assembly (10) may be mounted on each buffer plate (50). The buffer plate (50) may be moved to input the electrode assembly for a subsequent process, and the movement timing and interval may be adjusted according to the speed of the subsequent process. In other words, when the electrode assembly (10) is mounted on the buffer plate (50), the buffer plate (50) may be transported after a minimum buffering time has elapsed.

[0146] According to the present embodiment, a conductive plate (23) may be provided on the upper surface of the buffer plate (50). Unlike the conductive plate of the upper inspection device (10) described above, the conductive plate (23) has a fixed configuration and may thus be a part of the buffer plate (50). Accordingly, it may be referred to as a conductive mounting portion (60) of the buffer plate.

[0147] The electrode assembly (10) can be mounted on the current-carrying plate (23) and transported as one piece with the current-carrying plate (23).

[0148] According to this embodiment, damage to the lowermost separator can be inspected during the buffering period. To this end, probes (21, 22) are lowered and contact the leads (1, 2), and a tester applies current to the probes. If the applied current flows through the conducting plate and is detected by the tester, it can be determined that the lowermost separator of the electrode assembly is damaged.

[0149] In this embodiment, only the probes (21, 22) may be provided to be raised and lowered for inspection. The probes (21, 22) are provided independently of the buffer plate (50) and adjacent to the buffer plate (50), and are positioned above the buffer plate (50) through the probe bracket (26).

[0150] As the entire probe bracket (26) is raised and lowered, the probes (21, 22) can also be raised and lowered. The probes (21, 22) can be raised and lowered by driving a cylinder (not shown). In particular, the probe can be raised and lowered by the cylinder raising and lowering the probe bracket (26).

[0151] According to the lead welding device according to the present embodiment, damage to the uppermost separator and the lowermost separator of the electrode assembly can be detected by using a device or process for transferring the electrode assembly from a welding machine to an unloading machine and a device or process for transferring the electrode assembly after buffering it in the unloading machine.

[0152] Therefore, damage to the separator of the electrode assembly can be effectively detected in-line, without the need for separate additional processes or independent devices. Specifically, by detecting separator damage immediately prior to the process where the electrode assembly is combined with a battery case, such as a pouch, secondary batteries can be manufactured with higher reliability.

[0153] Meanwhile, according to one embodiment of the present invention, a control method for a welding device including a welding device for welding a lead to an electrode tab of an electrode assembly and an unloading device for moving the electrode assembly, after welding, to a subsequent process can be provided.

[0154] As illustrated in Fig. 9, a method or manufacturing process for manufacturing a secondary battery may include an electrode lead welding process. In particular, the electrode lead welding process (S20) may be necessarily performed in a process for manufacturing a secondary battery having a stacked electrode assembly.

[0155] The electrode lead welding process (S20) can be said to be a process of welding positive electrode tabs to positive leads and welding negative electrode tabs to negative leads in a stacked electrode assembly.

[0156] The welding process (S20) may be performed using a welding device. The welding device may include, in a narrow sense, a welding machine that directly performs welding, and may include an LMS that moves the electrode assembly for welding. The welding device may broadly include a loading device that moves the electrode assembly, on which the electrode assembly stacking process (S10) has been completed, to the welding machine, and an unloading device that moves the electrode assembly, on which the welding process (S20) has been completed, to a subsequent process, for example, an assembly process (S50).

[0157] The above control method may include a welding process (S20) of welding a lead to an electrode tab while sequentially moving the electrode assembly in a welding stage, a pick-up process (S30) of transferring the electrode assembly, for which the welding process has been completed, to a shuttle device of an unloading machine using a pick-and-place device, and a shuttle process (S40) of transferring the electrode assembly using the shuttle device.

[0158] According to this embodiment, it is preferable that the upper inspection process is performed in the pickup process (S30) and the lower inspection process is performed in the shuttle process (S40).

[0159] That is, in the above pickup process (S30), an upper inspection process can be performed using the pick-and-place device to check for damage to the uppermost separator of the electrode assembly. In order to perform the upper inspection process, it is preferable that a conductive plate that comes into contact with the upper surface of the electrode assembly is provided in a picker of the pick-and-place device. In addition, it is preferable that the pick-and-place device that performs the pickup process and the upper inspection process be a part of a welding device.

[0160] In addition, in the shuttle process (S40), a bottom inspection process may be performed using the shuttle device to check for damage to the bottommost separator of the electrode assembly. In order to perform the bottom inspection process, it is preferable that a conductive plate that comes into contact with the lower surface of the electrode assembly is provided on the shuttle device. In addition, it is preferable that the shuttle device that performs the shuttle process and the bottom inspection process be a part of a welding device.

[0161] The above welding, pick-up, and shuttle processes are performed continuously inline. That is, the welding, pick-up, and shuttle processes can be considered sub-processes within the overall inline process. The above inline process may include an upper inspection process and a lower inspection process. Preferably, the upper inspection process is performed during the pick-up process, and the lower inspection process is performed during the shuttle process.

[0162] The above welding process, pickup process, and shuttle process constitute an inline process that is performed continuously, and the upper inspection process and the lower inspection process are preferably part of the inline process. Therefore, the upper inspection process and the lower inspection process are preferably performed on the entire electrode assembly being manufactured, rather than on a portion of the electrode assembly. Of course, the inspection process may not be performed on an electrode assembly that is confirmed to be defective before the inspection process is performed.

[0163] Meanwhile, a stacking process (S10) is performed prior to the welding process (S20), and the electrode assembly manufactured by completing stacking through a loading machine can be transferred to a welding device. The electrode assembly for which welding is completed can be transferred to a subsequent assembly process (S50) through an unloading machine. The entire process from the stacking process (S10) to the assembly process (S50) can also be said to be an inline process that is performed continuously.

[0164] According to this embodiment, the separator is inspected for damage before moving from the welding process to the assembly process. Electrode assemblies with damaged separators may be judged defective during the activation process after the assembly process or after the activation process is completed. This means that defective electrode assemblies are not initially screened out and subsequent processes are performed without significance. For this reason, according to this embodiment, defective products can be screened out early, effectively reducing manufacturing costs, improving product quality, shortening manufacturing times, and enabling the construction and operation of compact equipment.

[0165] As described in the detailed description of the invention.

Claims

1. A pick-and-place device including a picker that supports the lower surface of an electrode assembly and moves the electrode assembly through three-axis movement, A current-carrying plate which is provided to move integrally with the picker and moves up and down with respect to the picker so as to selectively come into close contact with the upper surface of the electrode assembly; A probe which is provided to move integrally with the picker and moves up and down with respect to the picker so as to selectively contact the electrode leads of the electrode assembly; A pick-and-place device comprising a detector that applies current to the probe and detects whether the separator of the electrode assembly is damaged based on whether or not the current is detected through the current-carrying plate.

2. In paragraph 1, The above pick-and-place device is a pick-and-place device characterized in that it is provided between a welding device that welds a plurality of electrode tabs of an electrode assembly to electrode leads and an unloading device that moves the electrode assembly, on which the welding is completed, for a subsequent process.

3. In paragraph 1, A pick-and-place device characterized in that the pick-and-place device is provided to separate and move the electrode assembly from a pallet on which the electrode assembly is mounted and moves.

4. In paragraph 3, The above welding device is provided to sequentially weld the first electrode lead and the second electrode lead to the electrode assembly as the electrode assembly mounted on the pallet moves through the linear motion system. The pick-and-place device is characterized in that the pick-and-place device is provided to separate and move the electrode assembly from the pallet located at the transfer position after all welding is completed.

5. In paragraph 1, The above picker includes a lower picker that supports the lower surface of the electrode assembly and an upper picker provided on the upper portion of the lower picker. A pick-and-place device characterized in that the above-mentioned conductive plate is provided so as to be able to rise and fall between the lower picker and the upper picker.

6. In paragraph 5, A pick-and-place device characterized in that the picker includes a cylinder configured to elevate the energizing plate relative to the upper picker.

7. In paragraph 6, A pick-and-place device characterized in that one end of the cylinder is connected to the upper picker and the other end is connected to the conductive plate.

8. A control method for a welding device including a welding device for welding a lead to an electrode tab of an electrode assembly and an unloading device for moving the electrode assembly after welding is completed to a subsequent process. A welding process that welds leads to electrode tabs while sequentially moving the electrode assembly on the welding stage; A pick-up process in which the electrode assembly, after the welding process has been completed, is transferred to the shuttle device of the unloading machine using a pick-and-place device; Including a shuttle process for transporting the electrode assembly using the shuttle device, In the above pickup process, an upper inspection process is performed to inspect for damage to the uppermost separator of the electrode assembly using the pick-and-place device. A control method for a welding device, characterized in that a bottom inspection process is performed using the shuttle device in the above shuttle process to inspect whether the lowest separator of the electrode assembly is damaged.

9. In paragraph 8, The above pick-and-place device includes a picker having a conductive plate that comes into contact with the upper surface of the electrode assembly to perform the above upper inspection process, A control method for a welding device, characterized in that the above shuttle device includes a current-conducting plate that supports the lower surface of the electrode assembly.

10. In paragraph 9, A control method for a welding device, characterized in that the above welding process, pickup process, and shuttle process form an inline process that is performed continuously, and the upper inspection process and the lower inspection process are performed on the entire electrode assembly as part of the above inline process.

11. A welding machine that welds a plurality of electrode tabs of an electrode assembly to electrode leads while sequentially moving the electrode assembly through a linear motion system; An unloading machine that receives the electrode assembly, which has been welded, from the welding machine and transports it for subsequent processes; A pick-and-place device including a picker that supports the lower surface of an electrode assembly whose welding is completed in the welding machine and transfers the electrode assembly to the unloading machine through three-axis movement; and A secondary battery lead welding device including an upper detection device having a current-conducting plate provided on the picker and selectively in close contact with the upper surface of the electrode assembly, a probe selectively in contact with the electrode lead of the electrode assembly, and a detector that applies current to the probe and detects whether the uppermost separator of the electrode assembly is damaged based on whether current is detected through the current-conducting plate.

12. In paragraph 11, A secondary battery lead welding device characterized in that the above pick-and-place device is provided between the welding device and the unloading device.

13. In paragraph 11, A secondary battery lead welding device, characterized in that the pick-and-place device is provided to separate and move the electrode assembly from a pallet on which the electrode assembly is mounted and moved.

14. In paragraph 13, A secondary battery lead welding device characterized in that the welding machine is equipped to sequentially perform pre-welding of the first electrode tab, welding of the first electrode lead, pre-welding of the second electrode tab, and welding of the second electrode lead as the electrode assembly mounted on the pallet moves through the linear motion system.

15. In paragraph 14, A secondary battery lead welding device characterized in that the pick-and-place device is provided to separate and move the electrode assembly from the pallet located at the transfer position of the welding machine after the welding is completed.

16. In paragraph 15, The above picker includes a lower picker that supports the lower surface of the electrode assembly and an upper picker provided on the upper portion of the lower picker. A secondary battery lead welding device characterized in that the above-mentioned conductive plate is provided so as to be able to rise and fall between the lower picker and the upper picker.

17. In paragraph 16, A secondary battery lead welding device, characterized in that the picker includes a cylinder configured to elevate the conductive plate relative to the upper picker.

18. In paragraph 6, A secondary battery lead welding device characterized in that one end of the cylinder is connected to the upper picker and the other end is connected to the conductive plate.

19. In paragraph 11, A lead welding device characterized in that the above unloading device includes a shuttle device that transports the electrode assembly through the reciprocating movement of a buffer plate that supports the lower surface of the electrode assembly.

20. In paragraph 19, The above shuttle device includes a lower inspection device, The above lower inspection device is, A conductive plate provided on the upper surface of the buffer plate so as to be in close contact with the lower surface of the electrode assembly; A probe selectively contacting the electrode leads of the electrode assembly; and A secondary battery lead welding device characterized by including a detector that applies current to the probe and detects whether the lowest separator of the electrode assembly is damaged based on whether current is detected through the current-carrying plate.

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