Electrode supply device, electrode assembly manufacturing device using the same, electrode supply method, and electrode assembly manufacturing method using the same

Abstract

The present invention provides an electrode supply device, an electrode assembly manufacturing apparatus using the same, an electrode supply method, and an electrode assembly manufacturing method using the same.

Description

[Technical Field]

[0001] This application claims the benefit of the filing dates of Korean Patent Application No. 10-2023-0000693 filed with the Korean Intellectual Property Office on January 3, 2023, and Korean Patent Application No. 10-2023-0189250 filed with the Korean Intellectual Property Office on December 22, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to an electrode supply device, an electrode assembly manufacturing apparatus using the same, an electrode supply method, and an electrode assembly manufacturing method using the same. [Background technology]

[0003] Secondary batteries, unlike primary batteries, are rechargeable and have the potential to be small and have large capacities. As technological development and demand for mobile devices increases, the demand for secondary batteries as an energy source is rapidly increasing.

[0004] Secondary batteries are classified into coin-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries depending on the shape of the battery case. The electrode assembly attached to the inside of the battery case of a secondary battery is a power generating element that can be charged and discharged and is made up of a laminated structure of electrodes and a separator.

[0005] The electrode assemblies can be roughly classified into a jelly-roll type in which a sheet-like positive electrode and negative electrode coated with an active material are wound up with a separator interposed between them, a stack type in which a number of positive electrodes and negative electrodes are stacked in order with a separator interposed between them, and a stack-and-fold type in which a stack-type unit cell is wound up with a long separator film.

[0006] The electrode assembly is typically manufactured by receiving individual electrodes from a magazine in which a plurality of single electrodes are stacked, and in this process, there is a problem that the electrode to be supplied is not properly separated from the plurality of single electrodes stacked in the magazine, resulting in a defective manufactured electrode assembly.

[0007] Therefore, there is a need for a technology for appropriately separating electrodes for supply from among a plurality of electrodes stacked in a magazine. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention provides an electrode supply device, an electrode assembly manufacturing apparatus using the same, an electrode supply method, and an electrode assembly manufacturing method using the same. [Means for solving the problem]

[0009] One embodiment of the present invention provides an electrode supply device including: a magazine section in which a plurality of electrodes are stacked; an electrode pickup section that picks up a first electrode, which is the uppermost of the plurality of electrodes, and transports it toward a stack table; and an air supply section that injects air in the direction of an upper surface of the first electrode and a lower surface of a second electrode in contact with the first electrode, thereby reducing the pressure on the upper surface of the first electrode and the lower surface of the second electrode.

[0010] One embodiment of the present invention provides an apparatus for manufacturing an electrode assembly in which positive electrodes and negative electrodes are alternately arranged between folded separators, the apparatus including: a positive electrode supply unit that supplies the positive electrodes to a stack table; a negative electrode supply unit that supplies the negative electrodes to the stack table; a separator supply unit that supplies the separator to the stack table; a stack table in which a stack of positive electrodes, separators, and negative electrodes is manufactured so that the positive electrodes and negative electrodes are alternately arranged between the folded separators; and a press unit that heats and presses the stack to bond the positive electrodes, separators, and negative electrodes to manufacture an electrode assembly, wherein at least one of the positive electrode supply unit and the negative electrode supply unit includes the electrode supply device.

[0011] One embodiment of the present invention provides an electrode supply method including the steps of: injecting air in the direction of an upper surface of a first electrode that is the topmost among a plurality of electrodes stacked in a magazine section and a lower surface of a second electrode that is in contact with the first electrode, thereby reducing the pressure on the upper surface of the first electrode and the lower surface of the second electrode; and picking up the first electrode.

[0012] Finally, one embodiment of the present invention provides a method for manufacturing an electrode assembly in which positive and negative electrodes are alternately arranged between folded separators, the method comprising: supplying the positive electrode to a stacking table; supplying the negative electrode to a stacking table; supplying the separator to a stacking table; stacking the positive electrode, separator, and negative electrode on a stacking table so that the positive electrode and the negative electrode are alternately arranged between the folded separators to form a stack; and a heat pressing step of heating and pressurizing the stack to bond the positive electrode, separator, and negative electrode to form an electrode assembly, wherein at least one of the steps of supplying the positive electrode to the stacking table and supplying the negative electrode to the stacking table includes the electrode supplying method. [Effects of the Invention]

[0013] The electrode supplying method and electrode supplying device according to the embodiments of the present invention, the electrode assembly manufacturing device using the same, and the electrode assembly manufacturing method using the same can prevent two electrodes from being separated due to contact between the electrode surfaces or between the electrode surfaces and the separator.

[0014] The electrode supply method and electrode supply device according to the embodiments of the present invention, the electrode assembly manufacturing device using the device, and the electrode assembly manufacturing method using the method can prevent the phenomenon in which two electrodes do not separate, thereby increasing productivity.

[0015] Furthermore, secondary batteries manufactured using the same have excellent performance, especially in terms of the safety of the electrode assembly. [Brief explanation of the drawings]

[0016] [Figure 1] 4A to 4C are diagrams illustrating a process of separating electrodes in an electrode supplying device and an electrode supplying method according to an embodiment of the present invention. [Figure 2] 1 is a plan view illustrating an example of an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention. [Figure 3] 1 is a front view showing the concept of an electrode assembly manufacturing apparatus according to an embodiment of the present invention; [Figure 4] 1 is a cross-sectional view illustrating an example of a conventional electrode assembly. [Figure 5] 3 is a conceptual diagram illustrating a pressing process of a manufacturing method or apparatus for an electrode assembly according to an embodiment of the present invention; [Figure 6] 1(a) is a perspective view showing a first press section 50 according to one embodiment of the present invention, and FIG. 1(b) is a perspective view showing a second press section 60 according to one embodiment of the present invention. [Figure 7] 1 is a perspective view showing a stack table in an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention; [Figure 8] 1 is a perspective view showing a positive electrode mounting table in an electrode assembly manufacturing apparatus according to an embodiment of the present invention; [Figure 9] 1 is a perspective view showing a negative electrode mounting table in an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention; [Figure 10] 1 is a perspective view showing a first suction head in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 11] 3 is a bottom view showing a first suction head in the electrode assembly manufacturing apparatus according to an embodiment of the present invention. FIG. [Figure 12] 1 is a plan view showing a holding mechanism and a stack table in an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention. [Explanation of symbols]

[0017] 1. Electrode pickup section 2. The first electrode on the top of the stacked electrodes 3. Second electrode in contact with the first electrode 4. Other electrodes 7 Magazine Section 10...electrode assembly 11...Positive electrode 11a Positive electrode tab 12...Negative electrode 12a Negative electrode tab 14...Separation membrane 50 ···First Press Department 51 Gripper 51a Main body 51b...Fixed part 60 ···Second Press Department 60a, 60b: Second pressure block 100 Electrode assembly manufacturing apparatus 110 Stack Table 111 Table body 112 Stack Table Heater 120...Separation membrane supply section 121 Separation membrane heating section 122 Separation membrane roll 130 Positive electrode supply unit 131 Positive electrode placement table 132 Positive heater 133 Positive electrode roll 134 First cutter 135 No. 1 conveyor belt 136 Positive electrode supply head 140 Negative electrode supply unit 141 Negative electrode placing table 142 Negative electrode heater 143 Negative electrode roll 144 Second cutter 145 Second conveyor belt 146 Negative electrode supply head 150 Positive electrode stack section 151 First suction head 151a...Vacuum inlet 151b...Bottom surface 152 First head heater 153 First moving part 160 Negative electrode stack section 161 Second suction head 162 Second head heater 163 Second moving part 170 ···Holding mechanism 171 First holding mechanism 172 Second holding mechanism 180 ···Press Department 181 First pressure block 182 Second pressure block 183,184 Press heater S ···Laminate A: A thin layer of air A': Expanded air layer B Air supply section DETAILED DESCRIPTION OF THE INVENTION

[0018] While the present invention may be embodied in many different forms, it is to be understood that the invention is not limited to the embodiments set forth herein, and that the invention may be practiced in various different forms without departing from the spirit or scope of the present invention.

[0019] In this specification, when a part is said to "comprise" a certain component, this means that it may further include other components, rather than excluding other components, unless specifically stated to the contrary.

[0020] In this specification, "p to q" means "not less than p and not more than q."

[0021] In this specification, the term "electrode magazine" refers to a unit that functions to stack electrodes in a certain space inside, like bullets in a magazine.

[0022] In describing the present invention, detailed descriptions of related known techniques that may unnecessarily obscure the gist of the present invention will be omitted.

[0023] One embodiment of the present invention provides an electrode supply device including: a magazine section in which a plurality of electrodes are stacked; an electrode pickup section that picks up a first electrode, which is the uppermost of the plurality of electrodes, and transports it toward a stack table; and an air supply section that injects air in the direction of an upper surface of the first electrode and a lower surface of a second electrode in contact with the first electrode, thereby reducing the pressure on the upper surface of the first electrode and the lower surface of the second electrode, respectively.

[0024] In this specification, the term "electrode" refers to the electrode and / or a semi-finished electrode product. The semi-finished electrode product refers to all semi-assembled electrode products, such as coated electrodes, rolled electrodes, and notched electrodes, manufactured in the process of manufacturing an electrode assembly and a secondary battery including the electrode assembly. That is, in this specification, electrodes or semi-finished electrode products may be stacked in the magazine unit.

[0025] An electrode supply device according to an embodiment of the present invention is characterized in that it reduces the pressure on the upper surface of the first electrode and the lower surface of the second electrode using an air supply unit capable of injecting air. This feature makes it easier to separate the stacked electrodes by relatively increasing the pressure of the air layer existing between the first electrode and the second electrode, and prevents the two electrodes from being separated due to contact between the electrode surfaces.

[0026] As a result, the electrode assembly manufactured by the electrode assembly manufacturing apparatus according to the embodiment of the present invention has excellent performance.

[0027] The electrode supply device according to an embodiment of the present invention may include a magazine unit in which the electrodes are stacked. The magazine unit functions to stack the electrodes.

[0028] The electrode supply device according to one embodiment of the present invention may include an electrode pickup unit that picks up an uppermost first electrode from among the electrodes stacked inside the magazine unit and transports it to the stack table side.

[0029] More specifically, in one embodiment of the present invention, the electrode pickup unit may include an electrode fixing unit that fixes the first electrode; and an electrode transport unit that transports the first electrode fixed by the fixing unit toward the stack table.

[0030] In one embodiment of the present invention, the air supply unit is provided on one side of the magazine unit and includes an air inlet through which air can be injected; two air outlets through which air is sprayed onto the upper surface of the first electrode and the lower surface of the second electrode in contact with the first electrode; and a flow path connecting the air inlet and the two air outlets, and the air outlets may have a shape that advances in the direction of air injection and gradually decreases in diameter.

[0031] In one embodiment of the present invention, the apparatus may further include an electrode placement table on which the electrodes transported by the electrode supply device are placed and aligned in position. The electrodes placed on the electrode placement table may be stacked on a stack table by an electrode stacking unit described later.

[0032] One embodiment of the present invention provides an apparatus for manufacturing an electrode assembly in which positive electrodes and negative electrodes are alternately arranged between folded separators, the apparatus including: a positive electrode supply unit that supplies the positive electrodes to a stack table; a negative electrode supply unit that supplies the negative electrodes to the stack table; a separator supply unit that supplies the separator to the stack table; a stack table in which a stack of positive electrodes, separators, and negative electrodes is manufactured so that the positive electrodes and negative electrodes are alternately arranged between the folded separators; and a press unit that heats and presses the stack to bond the positive electrodes, separators, and negative electrodes to manufacture an electrode assembly, wherein at least one of the positive electrode supply unit and the negative electrode supply unit includes the electrode supply device.

[0033] In one embodiment of the present invention, the positive electrode supply unit includes the electrode supply device.

[0034] In one embodiment of the present invention, the negative electrode supply unit includes the electrode supply device.

[0035] In one embodiment of the present invention, the positive electrode supply section and the negative electrode supply section each include the electrode supply device.

[0036] That is, the positive electrode supply unit and the negative electrode supply unit may both supply positive electrodes and negative electrodes using the electrode supply device according to the present invention.

[0037] That is, an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention may include an electrode supply unit that supplies electrodes to a stack table, and the electrode supply unit may include an electrode placement table on which the electrodes are placed before being stacked on the stack table by the electrode stack unit. Furthermore, the electrodes transported by the electrode supply device according to the present invention may be placed on the electrode placement table and aligned in position. The aligned electrodes may be stacked on the stack table by the electrode stack unit. Furthermore, the electrodes may be positive or negative electrodes.

[0038] In this specification, manufacturing a stack in which the positive electrode and the negative electrode are alternately arranged between the folded separators is referred to as zigzag folding.

[0039] In this specification, the laminate may correspond to an unfinished electrode assembly, and the uppermost and lowermost ends of the electrode assembly may correspond to the upper and lower surfaces of the laminate, respectively, or the bottom and top surfaces of the unfinished electrode assembly.

[0040] That is, in one embodiment of the present invention, the positive electrode supply unit may include the positive electrode supply device, and the negative electrode supply unit may include the negative electrode supply device. The positive electrode supply device and the negative electrode supply device may each be an electrode supply device according to the present invention.

[0041] In addition, in the electrode assembly manufacturing apparatus according to one embodiment of the present invention, the positive electrode supply unit may include a positive electrode placing table on which the positive electrode is placed before being stacked on the stack table by the positive electrode stack unit, and the negative electrode supply unit may include a negative electrode placing table on which the negative electrode is placed before being stacked on the stack table by the negative electrode stack unit.

[0042] In one embodiment of the present invention, in order to stack the positive electrode, the separator, and the negative electrode so that the positive electrode and the negative electrode are alternately arranged between the folded separator, a method in which the stack table moves left and right, a method in which the separator moves left and right, or a method in which the stack table rotates may be used, and conventional techniques in the art may be applied to this.

[0043] The electrode assembly manufacturing apparatus according to an embodiment of the present invention may include a stack table moving unit that moves the stack table left and right, or a separation membrane guide unit that moves the separation membrane left and right. The stack table moving unit and the separation membrane guide unit may be configured in any manner as long as they function to move the stack table and the separation membrane left and right, respectively, and may be configured in any manner commonly used in the art.

[0044] In one embodiment of the present invention, the press unit may further include a pair of pressure blocks and a press heater for heating the pressure blocks, the pair of pressure blocks being moved in directions opposite to each other to apply surface pressure to the laminate, and the laminate being heated by the press heaters. In this case, in one embodiment of the present invention, the pair of pressure blocks may include the press heaters therein.

[0045] In one embodiment of the present invention, the stack may be heated by a heater contained within the stack table.

[0046] The pressure and temperature conditions for the heating and pressing by the pressing unit may be the same as those for the heat pressing step described below, and the same applies to the time (time conditions) for applying the heat and pressure.

[0047] Here, the pressure condition refers to the pressure applied by the pair of pressurizing blocks (or the pressurizing blocks for the stack table), and the temperature condition refers to the temperature of heat applied by a press heater or a heater included inside the stack table.

[0048] In one embodiment of the present invention, the heat-pressing device may further include a gripper for fixing the stack of the positive electrode, the separator, and the negative electrode during heating and pressure application by the press unit. Specifically, the gripper may be applied in a first heat-pressing step, which will be described later.

[0049] In one embodiment of the present invention, the press unit may include a first press unit and a second press unit. Specifically, the first press unit and the second press unit may be used in a first heat pressing step and a second heat pressing step, respectively, as described below, and the heating conditions and pressure conditions for the first heat pressing step and the second heat pressing step may be the same as those for the first heat pressing step and the second heat pressing step, as described below.

[0050] In one embodiment of the present invention, the first press unit may include a pair of first press blocks, and the press surfaces of the pair of first press blocks may include grooves corresponding to the grippers, and the press surfaces other than the grooves may be flat. That is, the first press unit may be used in the first heat pressing step described above.

[0051] In one embodiment of the present invention, the second press unit may include a pair of second press blocks, and the press surfaces of the pair of second press blocks may be flat. That is, the second press unit may be used in the second heat pressing step described above.

[0052] The apparatus for manufacturing a secondary battery according to an embodiment of the present invention may further include a holding mechanism for holding and fixing the laminate during the manufacturing process of the laminate.

[0053] In this specification, the term "holding mechanism" refers to a mechanism that grips the stacked structure on the stack table to stack the positive electrodes or negative electrodes in the process of manufacturing a stack of the positive electrodes, separators, and negative electrodes, with the positive electrodes and negative electrodes alternately arranged between the separators folded on the stack table, and has a different function from a gripper that grips the stacked structure in the process of heating and pressurizing the stacked structure. For specific operation processes of the holding mechanism, please refer to the description of the method for manufacturing a secondary battery described below.

[0054] One embodiment of the present invention provides an electrode supply method including the steps of: reducing the pressure on the upper surface of a first electrode and the lower surface of a second electrode in contact with the first electrode among the electrodes stacked in a magazine section; and picking up and transporting the first electrode among the electrodes stacked in the magazine section to supply the electrode to a stack table side.

[0055] An electrode supply method according to an embodiment of the present invention is characterized by including a step of reducing the pressure on the upper surface of a first electrode and the lower surface of a second electrode in contact with the first electrode among electrodes stacked in a magazine section. This feature makes it easier to separate the stacked electrodes by relatively increasing the pressure of the air layer existing between the first electrode and the second electrode in contact with the first electrode, and prevents the two electrodes from separating due to contact between the electrode surfaces.

[0056] As a result, the electrode assembly manufactured by the method for manufacturing an electrode assembly according to an embodiment of the present invention has excellent performance.

[0057] In one embodiment of the present invention, the method may further include stacking electrodes in the magazine unit. More specifically, in one embodiment of the present invention, the method may further include stacking two or more electrodes in the magazine unit.

[0058] In one embodiment of the present invention, the step of picking up and transporting a first electrode from among the electrodes stacked in the magazine section and supplying the electrode to the stack table side may include the steps of fixing the first electrode; and transporting the fixed first electrode to the stack table side.

[0059] In one embodiment of the present invention, the method may further include aligning the positions of the transported electrodes before supplying the electrodes to the stack table. The above description regarding the electrode placement table can be applied to this step.

[0060] In one embodiment of the present invention, the step of reducing the pressure on the upper surface of a first electrode and the lower surface of a second electrode in contact with the first electrode among the electrodes stacked in the magazine section may include the step of injecting air in the direction of the upper surface of a first electrode and the lower surface of a second electrode in contact with the first electrode among the electrodes stacked in the magazine section.

[0061] One embodiment of the present invention provides a method for manufacturing an electrode assembly in which positive and negative electrodes are alternately arranged between folded separators, the method comprising: supplying the positive electrode to a stacking table; supplying the negative electrode to the stacking table; supplying the separator to the stacking table; stacking the positive electrode, separator, and negative electrode on the stacking table so that the positive electrode and the negative electrode are alternately arranged between the folded separators to form a stack; and a heat pressing step of heating and pressurizing the stack to bond the positive electrode, separator, and negative electrode to form an electrode assembly, wherein at least one of the steps of supplying the positive electrode to the stacking table and supplying the negative electrode to the stacking table includes the electrode supplying method.

[0062] In one embodiment of the present invention, the step of supplying the positive electrode to the stack table side includes the electrode supply method.

[0063] In one embodiment of the present invention, the step of supplying the negative electrode to the stack table side includes the electrode supply method.

[0064] In one embodiment of the present invention, the step of supplying the positive electrode to the stack table side and the step of supplying the negative electrode to the stack table side each include the electrode supply method.

[0065] That is, the step of supplying the positive electrode to the stack table side and the step of supplying the negative electrode to the stack table side may both be performed by supplying the positive electrode and the negative electrode, respectively, using the electrode supply method according to the present invention.

[0066] In one embodiment of the present invention, the step of stacking the positive electrode, the separator, and the negative electrode on a stack table such that the positive electrode and the negative electrode are alternately arranged between the folded separators to manufacture a stack includes: (S1) stacking the negative electrodes on the stack table; (S2) stacking the separator on the stack table so that the separator covers an upper surface of the negative electrode stacked on the stack table; (S3) stacking a positive electrode on the surface of the separator covering the top surface of the negative electrode opposite to the surface that contacts the negative electrode; (S4) providing the separator to cover the upper surface of the positive electrode; (S5) stacking the negative electrode on the surface of the separator covering the upper surface of the positive electrode opposite to the surface that contacts the positive electrode; and (S6) providing the separator to cover the upper surface of the negative electrode; The steps (S1) to (S6) may be repeated one or more times, which means that the electrodes are stacked first on the stack table.

[0067] In one embodiment of the present invention, the step of stacking the positive electrode, the separator, and the negative electrode on a stack table such that the positive electrode and the negative electrode are alternately arranged between the folded separators to manufacture a stack includes: (SS1) stacking separation membranes on the stack table; (SS2) stacking a positive electrode on the separator; (SS3) providing the separator to cover the upper surface of the positive electrode; (SS4) stacking the negative electrode on the surface of the separator covering the upper surface of the positive electrode opposite to the surface that contacts the positive electrode; and (SS5) providing the separator to cover the upper surface of the negative electrode; The steps (SS1) to (SS5) may be repeated one or more times, which means that the separation membrane is first stacked on the stack table.

[0068] In one embodiment of the present invention, steps (S4), (S6), (SS3), and (SS5), i.e., steps of further supplying the separator to cover the upper surface of the positive electrode or the negative electrode, may be performed in one of a manner in which the stack table moves left and right, a manner in which the separator moves left and right, and a manner in which the stack table rotates.

[0069] In one embodiment of the present invention, the separation membrane may be provided in the form of a separation membrane sheet. That is, the additional separation membrane may be provided in a continuous form. Also, the "upper surface" may refer to the surface of the separation membrane or electrode opposite to the surface facing the stack table.

[0070] That is, in order to stack the positive electrode, the separator, and the negative electrode in a form in which the positive electrode and the negative electrode are alternately arranged between the folded separator, a method in which the stack table moves left and right, a method in which the separator moves left and right, or a method in which the stack table rotates may be used, and in this regard, conventional techniques in the art may be applied.

[0071] In this case, the stack may be held by a holding mechanism to maintain alignment of the stack during the process of adding the positive electrode, the negative electrode, and the separator, and a stack in which the positive electrode and the negative electrode are alternately arranged between the folded separators may be manufactured.

[0072] In one embodiment of the present application, the method for manufacturing the electrode assembly may further include a heat pressing step of heating and pressing the laminate along a lamination axis.

[0073] In addition, in one embodiment of the present application, the heat pressing step of applying heat and pressure along the lamination axis may include the steps of: moving the laminate between a pair of pressure blocks including a press heater; moving the pair of pressure blocks in directions opposite to each other along the lamination axis to apply surface pressure to the laminate; and heating the laminate with the press heater.

[0074] Furthermore, in one embodiment of the present application, the heat pressing step may include a first heat pressing step in which the laminate is gripped with a gripper and heated and pressurized; and a second heat pressing step in which, after the first heat pressing step, the gripper stops gripping and the laminate is heated and pressurized.

[0075] In one embodiment of the present application, the first heat pressing step may include the steps of: pressing the upper surface of the laminate using a gripper to fix the laminate; moving the laminate fixed by the gripper between a pair of pressure blocks including a press heater; moving the pair of pressure blocks in directions opposite to each other along the lamination axis of the laminate to apply surface pressure to the fixed laminate; and heating the fixed laminate by the press heater.

[0076] In one embodiment of the present application, the second heat pressing step may include the steps of: ceasing heating and pressing the laminate after the first heat pressing step; separating the grippers from the laminate; moving the laminate with the grippers separated between a pair of pressure blocks including a press heater; moving the pair of pressure blocks in opposite directions along the lamination axis of the laminate with the grippers separated to pressurize the laminate; and heating the laminate with the press heater.

[0077] In one embodiment of the present application, the pressurizing block used in the first heat pressing step may have grooves corresponding to the grippers.

[0078] In one embodiment of the present application, the step of moving the gripper away from the stack may include the steps of: ceasing to apply pressure to the top surface of the stack using the gripper; and moving the gripper away from the stack.

[0079] In addition, in the heat pressing step (including the first and second heat pressing steps), the step of moving the laminate between a pair of pressure blocks including a press heater may include not only the case where only the laminate itself is moved, but also the case where the laminate is moved together with a stack table while being placed on the stack table. In this case, the objects to be heated and pressed by the pair of pressure blocks and the press heater may refer to the laminate and the stack table.

[0080] In one embodiment of the present application, the first heat pressing step may involve heating and pressing the laminate at a temperature of 65°C to 90°C and a pressure of 1 MPa to 3 MPa for 10 to 30 seconds, or more preferably at a temperature of 65°C to 75°C and a pressure of 1.5 MPa to 2 MPa for 10 to 20 seconds.

[0081] In one embodiment of the present application, the secondary heat pressing step may heat and press the laminate under conditions of a temperature of 50°C to 90°C and a pressure of 1 MPa to 6 MPa for 5 to 60 seconds, preferably under conditions of a temperature of 65°C to 90°C and a pressure of 1.5 MPa to 6 MPa for 5 to 30 seconds, and more preferably under conditions of a temperature of 65°C to 85°C and a pressure of 3 MPa to 5.5 MPa for 7 to 25 seconds.

[0082] When heating and pressurizing are performed while satisfying the above conditions, the electrodes and separators of the laminate of the positive electrode, separator, and negative electrode can be easily bonded without damaging the positive electrode, separator, and negative electrode, and the performance of the manufactured electrode assembly can be excellent.

[0083] In one embodiment of the present application, the temperature, pressure, and time conditions of the heat pressing step may be the same as those of the second heat pressing step described above. That is, the heat pressing step may involve heating and pressing the laminate under conditions of a temperature of 50°C to 90°C and a pressure of 1 MPa to 6 MPa for 5 to 60 seconds, preferably a temperature of 65°C to 90°C and a pressure of 1.5 MPa to 6 MPa for 5 to 30 seconds. More preferably, the laminate may be heated and pressed under conditions of a temperature of 65°C to 85°C and a pressure of 3 MPa to 5.5 MPa for 7 to 25 seconds.

[0084] Hereinafter, a method and an apparatus for manufacturing a secondary battery according to an embodiment of the present invention will be described in more detail with reference to FIGS.

[0085] FIG. 1 illustrates a process for separating electrodes in an electrode supply method and electrode supply device according to one embodiment of the present invention. As shown in FIG. 1, a first electrode 2, which is the topmost electrode among a plurality of stacked electrodes, a second electrode 3 in contact with the first electrode, and a plurality of other electrodes 4 are stacked inside a magazine unit 7. The first electrode 2 is picked up and transported by an electrode pickup unit 1. A thin air layer A is formed between the first electrode 2 and the second electrode 3. An air outlet B provided on one side of the magazine unit reduces the pressure on the upper surface of the first electrode and the lower surface of the second electrode. As a result, the pressure between the second electrode 3 becomes relatively high, and the thin air layer A expands to form an air layer A', thereby widening the gap between the first electrode 2 and the second electrode 3 inside the magazine unit 7. The air injection may also cause some separation between the other plurality of electrodes 4 and the second electrode 3. Since the distance between the first electrode 2 and the second electrode 3 is increased, the electrode pickup unit 1 can pick up and transport only the first electrode 2.

[0086] Also, although not explicitly shown in the drawings, the air supply unit 8 includes an air inlet 8a through which air can be injected; two air outlets 8b through which air is sprayed onto the upper surface of a first electrode and the lower surface of a second electrode among the electrodes stacked in the magazine unit; and a flow path 8c connecting the air inlet and the air outlet, and the air outlet 8b may have a shape in which the diameter of the air outlet 8b gradually decreases as it advances in the air spray direction.

[0087] Fig. 2 is a plan view illustrating an exemplary apparatus for manufacturing an electrode assembly according to an embodiment of the present invention, and Fig. 3 is a front view illustrating the concept of the apparatus for manufacturing an electrode assembly according to an embodiment of the present invention. For convenience, Fig. 2 omits the holding mechanism 170 shown in Fig. 3, the pressing unit 180 located at the rear in the plan view is indicated by a dotted line, and Fig. 3 omits the separation membrane supply unit 120 shown in Fig. 2. For reference, the details described with reference to Fig. 1 can be applied to the parts indicated by dashed lines in Figs. 2 and 3.

[0088] 1 to 3, an electrode assembly manufacturing apparatus 100 according to an embodiment of the present invention includes a stack table 110, a separator supply unit 120 that supplies a separator 14, a cathode supply unit 130 that supplies a cathode 11, a cathode supply unit 140 that supplies anode 12, a cathode stacking unit 150 that stacks the cathode 11 on the stack table 110, anode stacking unit 160 that stacks the anode 12 on the stack table 110, and a press unit 180 that bonds the cathode 11, the separator 14, and the anode 12. The electrode assembly manufacturing apparatus 100 according to an embodiment of the present invention may further include a holding mechanism 170 that secures the cathode 11 and the anode 12 when they are stacked on the stack table 110.

[0089] In one embodiment of the present invention, the positive electrode, the separator, and the negative electrode may be heated and supplied to a stack table.

[0090] That is, the separation membrane supply unit may supply the separation membrane to the stack table while heating it, and the positive electrode supply unit and the negative electrode supply unit may supply the positive electrode and the negative electrode to the stack table while heating them, respectively.

[0091] 4 is a cross-sectional view showing an example of an electrode assembly. A secondary battery according to the present invention may include the electrode assembly.

[0092] 2 to 4, an apparatus 100 for manufacturing an electrode assembly according to an embodiment of the present invention is an apparatus for manufacturing an electrode assembly 10 by stacking a positive electrode 11, a separator 14, and a negative electrode 12.

[0093] As shown in Fig. 4, the electrode assembly 10 is generally a chargeable / dischargeable power generating element, and may be formed by alternately stacking and assembling a positive electrode 11, a separator 14, and a negative electrode 12. Here, the electrode assembly 10 may be formed, for example, by folding the separator 14 in a zigzag pattern, with the positive electrode 11 and the negative electrode 12 alternately arranged between the folded separator 14. In this case, as shown in Fig. 4, the electrode assembly 10 may be formed such that the outermost corners are wrapped by the separator 14.

[0094] In one embodiment of the present application, the separation membrane supply unit may further include a separation membrane roll on which the separation membrane is wound. The separation membrane wound on the separation membrane roll may be gradually unwound and supplied to the stack table. That is, the separation membrane may be in the form of a separation membrane sheet.

[0095] FIG. 5 is a perspective view illustrating an example of a press unit of an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention, and a state in which the press unit presses a laminate in the apparatus for manufacturing an electrode assembly according to an embodiment of the present invention.

[0096] 2, 3, and 5, the press unit 180 may include a pair of pressure blocks 181 and 182, which may be moved in a direction facing each other, and a stack of the positive electrode 11, the separator 14, and the negative electrode 12 may be disposed between the pressure blocks 181 and 182. Thereafter, the press unit 180 may apply heat and pressure to the stack, thereby pressing the stacked positive electrode 11, the separator 14, and the negative electrode 12 to bond them together.

[0097] The press unit 180 further includes press heaters 183 and 184 for heating the pair of pressure blocks 181 and 182, which can heat and press the laminate. This allows for better thermal fusion between the positive electrode 11, the separator 14, and the negative electrode 12 in the laminate, resulting in stronger adhesion.

[0098] The pair of pressure blocks 181, 182 may be formed so that the horizontal and vertical lengths of the pressure surfaces are longer than the horizontal and vertical lengths of the laminate. The pair of pressure blocks 181, 182 may include a first pressure block 181 and a second pressure block 182, which may be provided as rectangular blocks.

[0099] FIG. 6(a) is a perspective view showing a first press section 50 according to one embodiment of the present invention, and FIG. 6(b) is a perspective view showing a second press section 60 according to one embodiment of the present invention.

[0100] 6(a), the first press unit 50 can apply heat and pressure to the laminate S while it is fixed by the gripper 51. The first press unit 50 is composed of a pair of first press blocks 50a and 50b, and the pressurizing surfaces of the pair of first press blocks 50a and 50b are all flat except for a groove corresponding to the fixed portion 51b of the gripper 51.

[0101] The gripper 51 may include a main body 51a that corresponds to the length x and height y of the stack S or is wider than the length x and height y of the stack S, and a plurality of fixing portions 51b that are provided on one surface of the main body 51a and are columnar or plate-shaped along the width z direction of the stack S. Here, the length x of the stack S may refer to the longest part from one end to the other end of the stack S, the height y may refer to the distance in the stacking direction of the stack S, and the width z may refer to the distance across the top surface of the stack S.

[0102] The fixing portion 51b can be adjusted in position along the height direction of the main body 51a, and the fixing portion 51b can contact the upper and lower surfaces of the laminate S to fix the laminate S. Thereafter, a pair of first pressure blocks 50a and 50b included in the first press unit 50 are moved in directions facing each other to apply surface pressure to one or more of the laminate S and the gripper 51, thereby bonding the electrodes and the separators included in the laminate S.

[0103] 6(b), the second press unit 60 may finally heat and press the laminate S that has been primarily heated and pressed by the first press unit 50. The second press unit 60 includes a pair of second press blocks 60a and 60b, and the pair of press blocks 61 and 62 may move in directions opposite to each other to apply surface pressure to the laminate S. In addition, the pair of second press blocks 60a and 60b included in the second press unit 60 may all have flat press surfaces that come into contact with and press the laminate S.

[0104] FIG. 7 is a perspective view showing a stack table in an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention.

[0105] Referring to FIGS. 2, 3, and 7, the stack table 110 may have the positive electrodes 11, the separators 14, and the negative electrodes 12 stacked in a manner that the positive electrodes 11 and the negative electrodes 12 are alternately arranged between the folded separators 14.

[0106] The stack table 110 may also include a table body 111 on which the positive electrode 11, the separator 14, and the negative electrode 12 are stacked, and a stack table heater 112 that heats the table body 111 to heat the stacked stack S.

[0107] The positive electrode 11 may be composed of a positive electrode and the negative electrode 12 may be composed of a negative electrode, but the present invention is not necessarily limited to this. For example, the positive electrode 11 may be composed of a negative electrode and the negative electrode 12 may be composed of a positive electrode.

[0108] FIG. 8 is a perspective view showing a positive electrode placing table in an electrode assembly manufacturing apparatus according to one embodiment of the present invention.

[0109] 2, 3, and 8, the positive electrode supply unit 130 can supply the positive electrode 11 to the positive electrode stack unit 150 while heating it.

[0110] The positive electrode supply unit 130 may also include a positive electrode placement table 131 on which the positive electrode 11 is placed before being stacked on the stack table 110 by the positive electrode stack unit 150, and a positive electrode heater 132 that heats the positive electrode placement table 131 to heat the positive electrode 11.

[0111] Meanwhile, the positive electrode supply unit 130 may further include a positive electrode roll 133 around which the positive electrode 11 is wound in a sheet state, a first cutter 134 that cuts the sheet-like positive electrode 11 wound around the positive electrode roll 133 at regular intervals when it is unwound and supplied to form positive electrodes 11 of a predetermined size, a first conveyor belt 135 that moves the positive electrodes 11 cut by the first cutter 134, and a positive electrode supply head 136 that vacuum-sucks the positive electrodes 11 transported by the first conveyor belt 135 and places them on the positive electrode placement table 131. Here, when cutting the sheet-like positive electrode 11, the first cutter 134 may cut the positive electrode 11 so that a positive electrode tab 11a is formed protruding from an end portion.

[0112] In this case, the cut positive electrodes 11 may be stacked in a positive electrode magazine, and the description of FIG. 1 may be applied to a method of picking up the stacked positive electrodes 11 in the positive electrode magazine.

[0113] FIG. 9 is a perspective view showing a negative electrode placing table in an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention.

[0114] 2, 3, and 9, the negative electrode supply unit 140 can supply the negative electrode 12 to the negative electrode stack unit 160 while heating the negative electrode 12.

[0115] The negative electrode supply unit 140 may also include a negative electrode placing table 141 on which the negative electrode 12 is placed before being stacked on the stack table 110 by the negative electrode stack unit 160, and a negative electrode heater 142 that heats the negative electrode placing table 141 to heat the negative electrode 12.

[0116] Meanwhile, the negative electrode supply unit 140 may further include a negative electrode roll 143 around which the negative electrode 12 is wound in a sheet state, a second cutter 144 that cuts the sheet-like negative electrode 12 wound around the negative electrode roll 143 at regular intervals when it is unwound and supplied to form negative electrodes 12 of a predetermined size, a second conveyor belt 145 that moves the negative electrodes 12 cut by the second cutter 144, and a negative electrode supply head 146 that vacuum-sucks the negative electrodes 12 transported by the second conveyor belt 145 and places them on the negative electrode placement table 141. Here, when cutting the sheet-like negative electrode 12, the second cutter 144 may cut the negative electrode 12 so that a negative electrode tab 12a is formed protruding from an end portion.

[0117] In this case, the cut negative electrodes 12 may be stacked in a negative electrode magazine, and the method for picking up the stacked negative electrodes 12 in the negative electrode magazine can be the same as the description of FIG.

[0118] In one embodiment of the present invention, the positive electrode stack unit may include a first suction head that vacuum-sucks the positive electrode placed on the positive electrode placing table, and the negative electrode stack unit may include a second suction head that vacuum-sucks the negative electrode placed on the negative electrode placing table.

[0119] FIG. 10 is an oblique view showing a first suction head in an electrode assembly manufacturing apparatus according to one embodiment of the present invention, and FIG. 11 is a bottom view showing the first suction head in an electrode assembly manufacturing apparatus according to one embodiment of the present invention.

[0120] 2, 3, 10, and 11, the positive electrode stacking unit 150 can stack the positive electrodes 11 on the stack table 110.

[0121] The positive electrode stack unit 150 may also include a first suction head 151 and a first moving unit 153.

[0122] The first suction head 151 can vacuum-suck the positive electrode 11 placed on the positive electrode placement table 131. In this case, the first suction head 151 has a vacuum suction port 151a formed on a bottom surface 151b thereof, and can suck in the positive electrode 11 through the vacuum suction port 151a to fix the positive electrode 11 to the bottom surface 151b of the first suction head 151. Here, the first suction head 151 may have a passage formed therein that connects the vacuum suction port 151a to a vacuum suction device (not shown).

[0123] The first moving unit 153 can move the first suction head 151 to the stack table 110 so that the first suction head 151 can stack the positive electrode 11 placed on the positive electrode placing table 131 on the stack table 110.

[0124] Furthermore, the negative electrode stacking unit 160 can stack the negative electrodes 12 on the stack table 110. Here, the negative electrode stacking unit 160 may have the same structure as the above-described positive electrode stacking unit 150. In this case, the negative electrode stacking unit 160 may include a second suction head 161 and a second moving unit 163.

[0125] The second suction head 161 can vacuum-suck the negative electrode 12 placed on the negative electrode placing table 141. At this time, the second moving unit 163 can move the second suction head 161 to the stack table 110 so that the second suction head 161 can stack the negative electrode 12 placed on the positive electrode placing table 141 on the stack table 110.

[0126] FIG. 12 is a plan view showing a holding mechanism and a stack table in an apparatus for manufacturing an electrode assembly according to one embodiment of the present invention.

[0127] 2, 3 and 12, when the positive electrode 11 or negative electrode 12 is stacked on the stack table 110, the holding mechanism 170 can grip the positive electrode 11 or negative electrode 12 and fix it to the stack table 110.

[0128] In addition, when stacking the positive electrode 11 on the stack table 110, the holding mechanism 170 may pressurize and fix the upper surface of the positive electrode 11 stacked on the uppermost side of the stack table 110, and when stacking the negative electrode 12 on the stack table 110, the holding mechanism 170 may pressurize and fix the upper surface of the negative electrode 12 stacked on the uppermost side of the stack table 110. In addition, the holding mechanism 170 may pressurize and fix the upper surface of the stack of the positive electrode 11, the separator 14, and the negative electrode 12 stacked on the stack table 110.

[0129] That is, when the positive electrode 11 and the negative electrode 12 are positioned between the separators 14 and stacked to form a stack, the holding mechanism 170 holds the uppermost surface of the stack by applying pressure toward the stack table 110, thereby preventing the stack from coming off the stack table 110.

[0130] Meanwhile, the holding mechanism 170 includes, for example, a first holding mechanism 171 and a second holding mechanism 172 and can fix both sides of the positive electrode 11 or the negative electrode 12 .

[0131] As described above, taking the case where zigzag folding progresses while the stack table 110 rotates as an example, after the holding mechanism 170 grips the positive electrode 11 or the negative electrode 12, when the stack table 110 rotates, the separation membrane 14 is released from the separation membrane roll 122 in proportion to the amount of rotation of the stack table 110 and can be supplied to the stack table 110 side.

[0132] Meanwhile, for example, the holding mechanism 170 and the stack table 110 may be connected or coupled to a rotation device (not shown). Here, when the holding mechanism 170 grips the positive electrode 11 or the negative electrode 12, the rotation device can rotate the holding mechanism 170 and the stack table 110.

[0133] Thereafter, when the stacking of the positive electrode 11 and the negative electrode 12 between the separator 14 is completed, the stack is fixed with a gripper and then moved to the press unit, whereupon the stack can be heated and pressed by the press unit.

[0134] In one embodiment of the present invention, the stacking assembly may further include a rotating unit that rotates the stack table, wherein a positive electrode stacking unit is provided on one side of the rotating unit and a negative electrode stacking unit is provided on the other side of the rotating unit so that the separator can be zigzag folded in a manner such that it is positioned between the positive electrode and the negative electrode, and the rotating unit may alternately rotate the stack table to one side to face the first suction head of the positive electrode stack unit when stacking the positive electrode, and rotate the stack table to the other side to face the second suction head of the negative electrode stack unit when stacking the negative electrode.

[0135] The electrode assembly manufacturing apparatus according to another embodiment of the present invention may further include a vision device for performing a vision inspection of the positive electrode and the negative electrode.

[0136] The electrode assembly manufacturing apparatus according to another embodiment of the present invention may further include a rotating unit that rotates the stack table and a vision device that performs a vision inspection of the positive electrode and the negative electrode.

[0137] According to another embodiment of the present invention, the electrode assembly manufacturing apparatus may further include a stack table moving unit that moves the stack table left and right, or a separation membrane guide unit that moves the separator left and right, and may further include a vision device that performs vision inspection of the positive electrode and the negative electrode. The stack table moving unit and the separation membrane guide unit may be configured in any manner as long as they function to move the stack table and the separator left and right, respectively, and may be devices commonly used in the art.

[0138] In one embodiment of the present invention, the stack table moving unit may include a stack table moving unit that moves the stack table left and right, wherein a positive electrode stacking unit is provided on one side of the stack table and a negative electrode stacking unit is provided on the other side of the stack table so that zigzag folding is possible in a manner in which the separator is located between the positive electrode and the negative electrode, and the stack table moving unit may alternately move the stack table to one side to face the first suction head of the positive electrode stacking unit when stacking the positive electrode, and move the stack table to the other side to face the second suction head of the negative electrode stacking unit when stacking the negative electrode.

[0139] In one embodiment of the present invention, the stack table may include a separation membrane guide unit that moves the separation membrane left and right, and the separation membrane guide unit may repeatedly move the separation membrane supplied to the stack table left and right so that the separation membrane can be zigzag folded in a manner such that the separation membrane is located between the positive electrode and the negative electrode.

[0140] That is, the electrode assembly manufacturing apparatus according to the embodiment of the present invention may further include additional components depending on the manner in which the stack table is moved or the manner in which the separator is supplied.

[0141] In one embodiment of the present invention, the vision device may include a first camera and a second camera. The first camera can capture images of positive electrodes placed on a positive electrode placement table in the positive electrode supply unit, and the second camera can capture images of negative electrodes placed on a negative electrode placement table in the negative electrode supply unit. The stacking quality of the positive electrodes and negative electrodes can be inspected using the image information acquired through the images captured by the first and second cameras. More specifically, the placement positions, sizes, stacking conditions, etc. of the positive electrodes and negative electrodes can be inspected.

[0142] In one embodiment of the present invention, the positive electrode may be a positive electrode and the negative electrode may be a negative electrode, or conversely, the positive electrode may be a negative electrode and the negative electrode may be a positive electrode.

[0143] In this specification, a description of an apparatus for manufacturing an electrode assembly can be applied to a method for manufacturing an electrode assembly and the electrode assembly itself, and vice versa.

[0144] In one embodiment of the present invention, the positive electrode is prepared by, for example, coating a mixture of a positive electrode active material, a conductive material, and a binder on a positive electrode current collector and then drying the mixture, and optionally adding a filler to the mixture. Materials commonly used in the art may be used for this purpose.

[0145] Specifically, the positive electrode active material is, for example, a layered compound such as lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), or a compound substituted with one or more transition metals; 1+x Mn 2-x Lithium manganese oxides such as LiMnO4 (where x is 0 to 0.33), LiMnO3, LiMn2O3, and LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiFe3O4, V2O5, and Cu2V2O7; and the chemical formula LiNi 1-x M x Ni-site lithium nickel oxide represented by the chemical formula LiMnO2 (where M=Co, Mn, Al, Cu, Fe, Mg, B, or Ga, and x=0.01 to 0.3). 2-x M x Examples of such compounds include, but are not limited to, lithium manganese composite oxides represented by Li2Mn3MO8 (where M is Co, Ni, Fe, Cr, Zn, or Ta, and x is 0.01 to 0.1) or Li2Mn3MO8 (where M is Fe, Co, Ni, Cu, or Zn); LiMn2O4, in which part of the Li in the chemical formula is replaced with an alkaline earth metal ion; disulfide compounds; and Fe2(MoO4)3.

[0146] Specifically, the positive electrode current collector is not particularly limited as long as it has high conductivity without inducing chemical changes in the battery. For example, stainless steel, aluminum, nickel, titanium, baked carbon, or aluminum or stainless steel surface-treated with carbon, nickel, titanium, silver, etc. may be used, but in particular aluminum may be used. The current collector may have fine irregularities on its surface to increase the adhesive strength of the positive electrode active material, and may be in various forms such as a film, sheet, foil, net, porous material, foam, or nonwoven fabric. The positive electrode current collector may generally have a thickness of 3 μm to 500 μm.

[0147] The conductive material may typically be added in an amount of 1 to 50 wt % based on the total weight of the mixture containing the positive electrode active material. Such a conductive material is not particularly limited as long as it is conductive and does not induce chemical changes in the battery. Examples of such a conductive material include graphite such as natural graphite and artificial graphite; carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fiber and metal fiber; metal powders such as carbon fluoride, aluminum, and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; and conductive materials such as polyphenylene derivatives.

[0148] The binder is a component that aids in binding the active material and conductive material, etc., and in binding them to the current collector, and is typically added in an amount of 1 to 50 wt % based on the total weight of the mixture including the positive electrode active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butylene rubber, fluororubber, and various copolymers.

[0149] The filler is selectively used as a component for suppressing the expansion of the positive electrode, and is not particularly limited as long as it is a fibrous material without inducing chemical changes in the battery. For example, olefin polymers such as polyethylene and polypropylene; fibrous substances such as glass fiber and carbon fiber are used.

[0150] Also, in one embodiment of the present invention, the negative electrode is manufactured by applying, drying, and pressing the negative electrode active material on a negative electrode current collector, and if necessary, the same conductive material, binder, filler, etc. as described above may be selectively further included. In this case as well, substances commonly used in the art may be used.

[0151] Specifically, the negative electrode active material is, for example, carbon such as graphitizable carbon and graphite-based carbon; LixFe2O3 (0 ≤ x ≤ 1), LixWO2 (0 ≤ x ≤ 1), SnxMe 1-x Me' y O z (Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, Group 1, Group 2, Group 3 elements of the periodic table, halogen; 0 < x ≤ 1; 1 ≤ y ≤ 3; 1 ≤ z ≤ 8), etc. metal composite oxides; lithium metal; lithium alloy; silicon-based alloy; tin-based alloy; SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO 2、 Metal oxides such as Bi2O3, Bi2O4, and Bi2O5; conductive polymers such as polyacetylene; Li-Co-Ni-based materials, etc. can be used. Such a negative electrode current collector is not particularly limited as long as it has conductivity without inducing chemical changes in the battery. For example, copper, stainless steel, aluminum, nickel, titanium, fired carbon, those surface-treated with carbon, nickel, titanium, silver, etc. on the surface of copper or stainless steel, aluminum-cadmium alloy, etc. may be used. Also, similar to the positive electrode current collector, fine irregularities can be formed on the surface to strengthen the binding force of the negative electrode active material, and it may be used in various forms such as films, sheets, foils, nets, porous bodies, foams, non-woven fabric bodies, etc. Also, the negative electrode current collector may generally have a thickness of 3 μm to 500 μm.

[0152] In one embodiment of the present invention, the separation membrane may be an organic / inorganic composite porous safety-reinforcing separator (SRS) membrane. The SRS separation membrane may have a structure in which a coating layer component including inorganic particles and a binder polymer is coated on a polyolefin-based separation membrane substrate.

[0153] The SRS separator does not shrink at high temperatures due to the heat resistance of the inorganic particles, so that the elongation of the safety separator can be maintained even if the electrode assembly is penetrated by the needle-shaped conductor.

[0154] Such an SRS separator may have a uniform pore structure formed by the pore structure contained in the separator substrate itself and the interstitial volume between the inorganic particles, which are components of the coating layer. The pores not only significantly reduce external impacts applied to the electrode assembly, but also allow smooth movement of lithium ions through the pores, allowing a large amount of electrolyte to be filled, resulting in a high impregnation rate, thereby improving battery performance.

[0155] In one embodiment of the present invention, the separator has a separator excess portion that extends beyond the width of the positive electrode and the negative electrode on both sides in the width direction, and a coating layer that is thicker than the separator is formed on one or both sides of the separator excess portion to prevent the separator from shrinking.

[0156] In one embodiment of the present invention, the size of each of the excess parts of the separation membrane may be 5% to 12% based on the width of the separation membrane.

[0157] In one embodiment of the present invention, the coating layer may be coated on both sides of the separator with a size that is 50% to 90% of the width of the excess portion of the separator on one side, and the widths of the coating layers on both sides may be the same or different.

[0158] In one embodiment of the present invention, the coating layer may contain inorganic particles and a binder polymer.

[0159] In one embodiment of the present invention, examples of the polyolefin-based separation membrane component include high-density polyethylene, linear low-density polyethylene, low-density polyethylene, ultra-high-molecular-weight polyethylene, polypropylene, or derivatives thereof.

[0160] In one embodiment of the present invention, the thickness of the coating layer may be smaller than the thickness of the positive electrode or negative electrode. In a specific example, the thickness of the coating layer may be 30% to 99% of the thickness of the positive electrode or negative electrode.

[0161] In one embodiment of the present invention, the coating layer may consist of a wet coating or a dry coating.

[0162] In one embodiment of the present invention, the substrate and the coating layer are present in a form in which the pores on the surface of the polyolefin-based separator substrate and the coating layer are intertwined (anchoring), thereby allowing for a strong physical bond between the separator substrate and the active layer. In this case, the substrate and the active layer may have a thickness ratio of 9:1 to 1:9, particularly 5:5, taking into account the physical bonding strength and the pore structure present on the separator.

[0163] In one embodiment of the present invention, the inorganic particles may be inorganic particles commonly used in the art. The inorganic particles function as spacers that allow the formation of void spaces between inorganic particles, forming micropores, and maintaining their physical shape. In addition, the inorganic particles generally have physical properties that do not change even at high temperatures of 200°C or higher, so the formed oil / inorganic composite porous film has excellent heat resistance.

[0164] Furthermore, the inorganic particles are not particularly limited as long as they are electrochemically stable. That is, the inorganic particles that can be used in the present invention are not particularly limited as long as they do not undergo oxidation and / or reduction reactions within the operating voltage range of the applied battery (e.g., 0 to 5 V based on Li / Li+). In particular, when inorganic particles with ion-transfer capabilities are used, those with as high an ion conductivity as possible are preferred because they can increase the ion conductivity within the electrochemical device and improve performance. Furthermore, inorganic particles with high density are not only difficult to disperse during coating but also result in weight increase during battery fabrication, so those with as low a density as possible are preferred. Furthermore, inorganic particles with high dielectric constants contribute to increasing the degree of dissociation of electrolyte salts, such as lithium salts, in the liquid electrolyte, thereby improving the ion conductivity of the electrolyte solution.

[0165] For the above reasons, the inorganic particles may be at least one selected from the group consisting of inorganic particles having piezoelectricity and inorganic particles having lithium ion transport ability.

[0166] The piezoelectric inorganic particles are non-conductors under normal pressure, but when a certain pressure is applied, they change their internal structure and become electrically conductive. They not only exhibit high dielectric constant characteristics with a dielectric constant of 100 or more, but also have the function of generating a potential difference between the two surfaces when tensioned or compressed by applying a certain pressure, generating charges on one side and negatively charging the other.

[0167] When inorganic particles having the above-described characteristics are used as a coating layer component, if an internal short circuit occurs between the electrodes due to an external impact such as a needle-shaped conductor, the inorganic particles coated on the separator not only prevent direct contact between the positive electrode and the negative electrode, but also generate a potential difference within the particles due to the piezoelectricity of the inorganic particles. This allows electrons to move between the electrodes, i.e., a minute current to flow, resulting in a gradual decrease in the battery voltage and thereby improved safety.

[0168] Examples of inorganic particles having piezoelectricity include BaTiO3, Pb(Zr,Ti)O3 (PZT), Pb 1-x La x Zr 1-y Ti y O3(PLZT), PB(Mg3Nb 2 / 3 )O3-PbTiO3 (PMN-PT) and hafnia (HfO2), but is not limited thereto.

[0169] The inorganic particles having lithium ion transport ability refer to inorganic particles that contain lithium but do not store lithium but have the function of transporting lithium ions. The inorganic particles having lithium ion transport ability can transport lithium ions through a type of defect present inside the particle structure, thereby improving the lithium ion conductivity in the battery and thereby improving the battery performance.

[0170] Examples of inorganic particles having lithium ion transfer ability include lithium phosphate (Li3PO4), lithium titanium phosphate (Li x Ti y (PO4)3,0 <x<2、0<y<3)、リチウムアルミニウムチタニウムホスフェート(Li x Al y Ti z (PO4)3,0 <x<2、0<y<1、0<z<3)、(LiAlTiP) x O y Type glass(0 <x<4、0<y<13)、リチウムランタンチタネート(Li x La y TiO3, 0 <x<2、0<y<3)、リチウムゲルマニウムチオホスフェート(Li x Ge y P z S w , 0 <x<4、0<y<1、0<z<1、0<w<5)、リチウムナイトライド(Li x N y , 0 <x<4、0<y<2)、SiS2(Lix Si y S z (where 0 < x < 3, 0 < y < 2, 0 < z < 4) system glass and P2S5 (Li x P y S z may be one or more selected from the group consisting of (where 0 < x < 3, 0 < y < 3, 0 < z < 7) system glass, but is not limited thereto.

[0171] The composition ratio of the inorganic particles and the binder polymer, which are the coating layer components, is not greatly restricted, but can be adjusted within the range of 10:90 to 99:1% by weight, and the range of 80:20 to 99:1% by weight is preferred. If it is less than the 10:90% by weight ratio, the content of the polymer becomes too large, and the pore size and porosity decrease due to the reduction of the empty space formed between the inorganic particles, leading to a decrease in the final battery performance. Conversely, if it exceeds the 99:1% by weight ratio, the polymer content is too small, so the adhesive force between the inorganics becomes weak, and the mechanical properties of the final oil / inorganic composite porous separation membrane may decrease.

[0172] In one embodiment of the present invention, the binder polymer may be a binder polymer commonly used in the art.

[0173] In the oil / inorganic composite porous separation membrane, the coating layer may further contain other commonly known additives in addition to the aforementioned inorganic particles and binder polymer.

[0174] In one embodiment of the present invention, the coating layer can also be used as the active layer.

[0175] As described above, the present invention has been described in detail with specific embodiments, but this is for specifically explaining the present invention, and the manufacturing apparatus for the electrode assembly according to the present invention is not limited thereto. It can be said that various implementations are possible by those with ordinary knowledge in the art within the technical idea of the present invention.

Claims

1. a magazine section in which a plurality of electrodes are stacked; an electrode pickup unit that picks up a first electrode that is located at the top of the plurality of electrodes; and an air supply unit that injects air toward the upper surface of the first electrode and the lower surface of the second electrode in contact with the first electrode to reduce the pressure on the upper surface of the first electrode and the lower surface of the second electrode, respectively; An electrode supply device comprising:

2. The electrode pickup unit an electrode fixing portion that fixes the first electrode; and an electrode transport section that transports the first electrode fixed by the electrode fixing section to the stack table side; 10. The electrode supply device of claim 1, comprising:

3. The air supply unit is Air inlet for injecting air; two air ejection ports for ejecting air onto the upper surface of the first electrode and the lower surface of the second electrode; and A flow path connecting the air inlet and the air outlet Including, The electrode supply device according to claim 1 , wherein the air ejection port has a shape in which the diameter of the flow path gradually decreases as the air ejection port advances in the air ejection direction.

4. An apparatus for manufacturing an electrode assembly in which positive and negative electrodes are alternately arranged between folded separators, comprising: a positive electrode supply unit that supplies the positive electrode to the stack table side; a negative electrode supply unit that supplies the negative electrodes to the stack table side; a separation membrane supply unit that supplies the separation membrane to the stack table side; a stack table on which a stack of the positive electrodes, the separators, and the negative electrodes is manufactured, with the positive electrodes and the negative electrodes alternately arranged between the folded separators; and A press unit that heats and presses the laminate to bond the positive electrode, the separator, and the negative electrode together to manufacture the electrode assembly. Including, 4. An apparatus for manufacturing an electrode assembly, wherein at least one of the positive electrode supply unit and the negative electrode supply unit includes the electrode supply device according to claim 1.

5. a step of reducing pressure on an upper surface of a first electrode at the top of the plurality of electrodes stacked in the magazine section and a lower surface of a second electrode in contact with the first electrode; and Picking up the first electrode An electrode supply method comprising:

6. The step of picking up and transporting the first electrode and supplying the electrode to a stack table side includes: securing the first electrode; and transporting the fixed first electrode to a stack table side; 6. The electrode supply method of claim 5, comprising:

7. The step of reducing the pressure on the upper surface of the first electrode and the lower surface of the second electrode comprises: injecting air toward the upper surface of the first electrode and the lower surface of the second electrode; 6. The electrode supply method of claim 5, comprising:

8. A method for manufacturing an electrode assembly in which a positive electrode and a negative electrode are alternately arranged between folded separators, comprising: supplying the positive electrode to a stack table side; supplying the negative electrode to a stack table side; supplying the separation membrane to a stack table; stacking the positive electrodes, the separators, and the negative electrodes on a stack table so that the positive electrodes and the negative electrodes are alternately arranged between the folded separators to manufacture a stack; and a heat pressing step of heating and pressing the laminate to bond the positive electrode, the separator, and the negative electrode together to manufacture the electrode assembly; Including, A method for manufacturing an electrode assembly, wherein at least one of the steps of supplying the positive electrode to the stack table side and supplying the negative electrode to the stack table side includes the electrode supply method according to any one of claims 5 to 7.

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