Apparatus and method for membrane heat sealing and stacking

Abstract

Disclosed herein may be an apparatus and method for membrane heat sealing and stacking. The apparatus may include: a continuous diaphragm supply unit configured to supply a diaphragm in a continuous sheet form; a heat sealing unit configured to heat-seal the two diaphragms supplied from the continuous diaphragm supply unit; an electrode plate insertion unit configured to insert an electrode plate between the two heat-sealed diaphragms; and a cutting unit configured to cut the two diaphragms between which the electrode plates are inserted to produce a unit group.

Description

[0001] This application claims priority and benefit to Korean Patent Application No. 10-2024-0157526, filed on November 7, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates to an apparatus and method for heat-sealing and stacking diaphragms, and more specifically, to an apparatus and method for heat-sealing and stacking diaphragms, wherein electrode plates are physically contacted with the sealing portion via guide lines formed by the heat seal, thereby achieving automatic alignment. Background Technology

[0003] Unlike primary batteries, which are not designed for recharging, secondary batteries are designed for discharging and recharging. Low-capacity secondary batteries are used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity secondary batteries are widely used to power motors in hybrid or electric vehicles and as power sources for energy storage. A secondary battery includes an electrode assembly containing positive and negative electrodes, a housing that houses the electrode assembly, and terminals that connect to the electrode assembly.

[0004] The information disclosed in this background section is intended to enhance the understanding of the background art of this disclosure, and therefore may contain information that does not constitute related (or prior art). Summary of the Invention

[0005] Embodiments of this disclosure aim to provide an apparatus and method for heat-sealing and stacking diaphragms, wherein electrode plates are physically contacted with the sealing portion via guide lines formed by the heat seal, thereby achieving automatic alignment.

[0006] However, the technical problems to be solved by this disclosure are not limited to the above-mentioned problems, and those skilled in the art will clearly understand, through the description of this disclosure, other problems not mentioned herein, as well as the aspects and features of this disclosure that will solve these problems.

[0007] An apparatus for heat-sealing and stacking diaphragms according to an embodiment of the present disclosure may include: a continuous diaphragm supply unit configured to supply diaphragms in the form of continuous sheets; a heat-sealing unit configured to heat-seal two diaphragms supplied from the continuous diaphragm supply unit; an electrode plate insertion unit configured to insert an electrode plate between the two heat-sealed diaphragms; and a cutting unit configured to cut the two diaphragms between which the electrode plates are inserted to produce a unit assembly.

[0008] In an embodiment, the continuous diaphragm supply unit may include: a roller unit configured to supply diaphragms in the form of continuous sheets; and a conveyor belt configured to simultaneously receive diaphragms from the roller unit and convey the diaphragms at the same speed.

[0009] In one embodiment, the heat-sealing unit may include: a silicone rubber portion; a heat-sealing strip provided on one side of the silicone rubber portion for forming a heat-sealing area on both diaphragms; and a sealing motor configured to move the silicone rubber portion and the heat-sealing strip upwards or downwards. The silicone rubber portion and the heat-sealing strip can provide uniform pressure to the diaphragms.

[0010] In one embodiment, the heat-sealing unit may include a first heat-sealing unit and a second heat-sealing unit, which are sequentially positioned and each has a heat-sealing strip in a different region. The first heat-sealing unit may be configured to form a first heat-sealing area on one side of the two diaphragms, and the second heat-sealing unit may be configured to form a second heat-sealing area on the other side of the two diaphragms.

[0011] In one embodiment, the heat seal strip may be coated with Teflon material to prevent adhesion between the diaphragm and the heat seal strip.

[0012] In an embodiment, the electrode plate insertion unit can be configured to insert a first electrode plate into a first heat-sealing area and a second electrode plate into a second heat-sealing area.

[0013] In one embodiment, the first electrode plate and the second electrode plate may be inserted in opposite directions and aligned during insertion by contacting the first heat-sealing area and the second heat-sealing area, respectively.

[0014] In one embodiment, the cutting unit may include: a cutter configured to cut two diaphragms inserted therebetween into an electrode plate; and a cutting motor configured to move the cutter up or down.

[0015] In one embodiment, the apparatus may include a stacking unit configured to receive and stack the produced cell groups and align the produced cell groups.

[0016] In one embodiment, the stacking unit may include: a stacking platform configured to receive the produced unit group and tilt to allow the unit group to slide downwards; a stop configured to stop and align the sliding unit group; and a stacking motor configured to move the stacking platform up or down.

[0017] A method for heat-sealing and stacking diaphragms according to an embodiment of the present disclosure may include: supplying diaphragms in the form of continuous sheets via a continuous diaphragm supply unit; heat-sealing two diaphragms supplied from the continuous diaphragm supply unit via a heat-sealing unit; inserting an electrode plate between the two heat-sealed diaphragms via an electrode plate insertion unit; and cutting the two diaphragms between which the electrode plate is inserted via a cutting unit to produce a unit assembly.

[0018] In an embodiment, the supply of the diaphragm may include: supplying a diaphragm in the form of a continuous sheet through a roller unit of a continuous diaphragm supply unit; and simultaneously receiving two diaphragms from the roller unit through a conveyor belt of the continuous diaphragm supply unit, and conveying the two diaphragms at the same speed.

[0019] In an embodiment, the heat sealing unit may include: a silicone rubber portion; a heat sealing strip provided on one side of the silicone rubber portion; and a sealing motor; and heat sealing may include: moving the silicone rubber portion and the heat sealing strip upward or downward by means of the sealing motor, and forming a heat sealing area on the two diaphragms by means of the heat sealing strip.

[0020] In an embodiment, the heat sealing unit may include a first heat sealing unit and a second heat sealing unit, the first heat sealing unit and the second heat sealing unit being positioned sequentially and each having a heat sealing strip in a different region; and the heat sealing may include: forming a first heat sealing area on one side of the two diaphragms by the first heat sealing unit; and forming a second heat sealing area on the other side of the two diaphragms by the second heat sealing unit.

[0021] In an embodiment, the method may further include coating the heat seal with a Teflon material to prevent adhesion between the diaphragm and the heat seal.

[0022] In an embodiment, inserting the electrode plate may include: inserting a first electrode plate into a first heat-sealing area; and inserting a second electrode plate into a second heat-sealing area.

[0023] In an embodiment, the insertion of the first electrode plate and the second electrode plate may include inserting the first electrode plate and the second electrode plate in opposite directions, and aligning the first electrode plate and the second electrode plate by contacting the first heat-sealing area and the second heat-sealing area respectively during insertion.

[0024] In an embodiment, the cutting unit may include a cutter and a cutting motor; and the production of the unit group may include moving the cutter up or down by the cutting motor and cutting two diaphragms in which the electrode plates are inserted by the cutter.

[0025] In an embodiment, the method may further include receiving and stacking the produced cell groups via stacking cells, while aligning the produced cell groups.

[0026] In an embodiment, the stacking unit may include: a stacking platform configured to receive the produced unit group and tilt to allow the unit group to slide downwards; a stop configured to stop and align the sliding unit group; and a stacking motor; and the receiving and stacking of the unit group may include moving the stacking platform up or down via the stacking motor.

[0027] According to embodiments of this disclosure, an advantage that can be provided is that specific portions of the diaphragm can be selectively heat-sealed using a silicone rubber portion and a heat-sealing strip.

[0028] Furthermore, according to embodiments of this disclosure, when the diaphragm is stacked on a stacking platform after being cut, the stacking platform can move up or down to minimize damage to the diaphragm.

[0029] Furthermore, for negative and positive electrode plates of different sizes, the advantage is that multiple materials of different sizes can be precisely aligned by using guide lines of different sizes to align the corresponding electrode plates.

[0030] However, the aspects and features of this disclosure are not limited to those described herein, and those skilled in the art will clearly understand other aspects and features not mentioned from the detailed description herein. Attached Figure Description

[0031] The following accompanying drawings illustrate embodiments of the present disclosure and, together with the detailed description of the present disclosure, further describe aspects and features of the present disclosure. Therefore, the present disclosure should not be construed as limited to the drawings.

[0032] Figure 1A This is a top-view perspective view of a prismatic secondary battery.

[0033] Figure 1B It is along Figure 1A The cross-sectional view taken from line I-I'.

[0034] Figure 2 This is a view illustrating an apparatus for heat sealing and stacking diaphragms according to an embodiment of the present disclosure.

[0035] Figure 3 This is a view of a continuous diaphragm supply unit illustrating an apparatus for diaphragm heat sealing and stacking according to an embodiment of the present disclosure.

[0036] Figure 4A This is a view of a heat-sealing unit illustrating an apparatus for heat-sealing and stacking diaphragms according to an embodiment of the present disclosure.

[0037] Figure 4B This is a view illustrating a diaphragm sealed by a heat-sealing unit of an apparatus for heat-sealing and stacking diaphragms according to an embodiment of the present disclosure.

[0038] Figure 5 This is a view of a cutting unit illustrating an apparatus for heat sealing and stacking diaphragms according to an embodiment of the present disclosure.

[0039] Figure 6 This is a view of stacked units used to describe an apparatus for heat sealing and stacking diaphragms according to embodiments of the present disclosure.

[0040] Figure 7This is a view used to describe a method of aligning electrode plates using an apparatus for heat sealing and stacking diaphragms according to embodiments of the present disclosure.

[0041] Figure 8 This is a flowchart describing a method for heat sealing and stacking diaphragms according to embodiments of the present disclosure. Detailed Implementation

[0042] Exemplary embodiments of this disclosure will be described in detail herein with reference to the accompanying drawings. Before description, it should be noted that the terms or words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings, but should be understood to have meanings and concepts consistent with the spirit of this disclosure, based on the inventor's ability to appropriately define the concept of each term in order to best describe his / her own disclosure. Therefore, since the embodiments described in this specification and the configurations illustrated in the drawings are merely examples of this disclosure and do not cover all the technical ideas of this disclosure, it should be understood that various changes and modifications can be made at the time of filing this application.

[0043] It will be further understood that, when used herein, the terms “comprising” and / or “including” specify the presence of the said feature, integer, step, operation, element, component, and / or group thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0044] To facilitate understanding of this disclosure, the drawings are not to scale, and the dimensions of some components may be enlarged. It should be noted that in different embodiments, the same reference numerals indicate the same components.

[0045] Referring to two compared elements, features, etc., as "identical" means that they are "substantially identical." Therefore, the phrase "substantially identical" can include deviations considered low in the art, such as 5% or less. The uniformity of any parameter in a given region may mean that it is uniform from an average perspective.

[0046] While terms such as "first" and / or "second" are used to describe various components, these components are certainly not limited by these terms. These terms are used only to distinguish one component from another. Therefore, unless specifically stated otherwise, a first component may be referred to as a second component without departing from the teachings of the exemplary embodiments.

[0047] Throughout this specification, unless otherwise stated, each element may be singular or plural.

[0048] Arranging any component "above (or below)" or "on (or under)" a component may mean that any component is configured to contact the upper (or lower) surface of the component, and other components may be located between the component and any components positioned on (or below) the component.

[0049] It will be understood that when a component is referred to as “connected,” “joined,” or “engaged” to another component, it can be directly “connected,” “joined,” or “engaged” to the other component, or indirectly “connected,” “joined,” or “engaged” to the other component in the presence of other components in between.

[0050] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. The use of “may” in describing embodiments of this disclosure refers to “one or more embodiments of this disclosure.” Expressions such as “at least one of…” and “one or more of…” before / after the list of elements modify the entire list of elements, but not individual elements in the list.

[0051] Unless otherwise stated, throughout the specification, when “A and / or B” is stated, it means A, B, or A and B. Furthermore, unless explicitly stated otherwise, when “C to D” is stated, it means C or more and D or fewer.

[0052] When phrases such as “at least one of A, B and C”, “at least one of A, B or C”, “at least one selected from the group of A, B and C” or “at least one selected from A, B and C” are used to specify a list of elements A, B and C, the phrase can refer to any and all suitable combinations.

[0053] The term “use” may be considered synonymous with the term “utilization”. As used herein, the terms “approximately,” “about,” and similar terms are used as approximate terms rather than terms of degree and are intended to take into account the inherent variations in measurements or calculations that would be apparent to a person of ordinary skill in the art.

[0054] It will be understood that while the terms first, second, third, etc., may be used to describe various elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or segment from another element, component, region, layer, or segment. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or segment discussed herein may be referred to as the second element, component, region, layer, or segment.

[0055] To facilitate explanation when describing the relationship between one element or feature and another element or feature as shown in the figures, spatial relative terms such as “below,” “under,” “down,” “above,” and “above” are used herein. It will be understood that, in addition to the orientation depicted in the figures, spatial relative positions are also intended to cover different orientations of the device in use or operation. For example, if the device in the figures is flipped, any element described as “below” or “under” another element would be oriented as “above” or “above” another element. Therefore, the term “below” can include both upward and downward directions.

[0056] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit this disclosure.

[0057] This disclosure will be described in detail with reference to the accompanying drawings.

[0058] Electrode assemblies for secondary batteries are formed by inserting positive and negative electrode plates between a separator and stacking the inserted plates. Therefore, the apparatus used for stacking the separator and electrode plates is called a stacking apparatus. Conventional stacking apparatuses suffer from relatively low productivity due to the time consumed in identifying and aligning the electrode plates (a time consumption that makes ultra-high-speed stacking impossible). Furthermore, automation and high-precision stacking are difficult due to resolution limitations of components such as motors and cameras.

[0059] Examples of secondary batteries include coin-shaped, cylindrical, prismatic, and pouch-shaped types. This disclosure is essentially applicable to prismatic secondary batteries. Therefore, prismatic secondary batteries will be briefly described first before describing embodiments of this disclosure.

[0060] Figure 1A This is a top-view perspective view of a prismatic secondary battery. Figure 1B It is along Figure 1A The cross-sectional view taken from line I-I'.

[0061] First, the description Figure 1A The image shows the appearance of a prismatic secondary battery.

[0062] The housing 51 defines the overall appearance of the prismatic secondary battery and can be made of a conductive metal such as aluminum, aluminum alloy, or nickel-plated steel. Furthermore, the housing 51 provides space for housing the electrode assembly.

[0063] The cover assembly 60 may include a cover plate 61 that covers the opening of the housing 51, and the cover assembly 60 and the cover plate 61 may be made of a conductive material. Here, the first terminal 63 and the second terminal 62 may be electrically connected to corresponding positive and negative electrodes (or negative and positive electrodes) inside the housing 51, and may be mounted to protrude outward through the cover plate 61.

[0064] The cover plate 61 may be equipped with an electrolyte inlet 64 formed for mounting a sealing plug and a vent 66 formed with a notch 65. The vent 66 is used to degas the secondary battery, that is, to discharge the gas generated inside the secondary battery.

[0065] refer to Figure 1B The internal structure of the prismatic secondary battery and its connection structure with the cover assembly 60 will be described.

[0066] like Figure 1B As illustrated, a prismatic secondary battery may substantially include an electrode assembly 40, a first current collector 41, a first terminal 62, a second current collector 42, a second terminal 63, and a cover assembly 60.

[0067] Electrode assembly 40 can be formed by winding or stacking a first electrode plate, a diaphragm, and a second electrode plate in the form of a plate or film. When electrode assembly 40 is a wound stack, it can have a winding axis parallel to the longitudinal direction of housing 51. Electrode assembly 40 can be stacked rather than wound, but the shape of electrode assembly 40 is not limited in this disclosure. Furthermore, electrode assembly 40 can be a Z-stacked electrode assembly in which the first electrode plate and the second electrode plate are inserted into both sides of a diaphragm that is bent into a Z-stack. Furthermore, electrode assembly 40 can be composed of one or more electrode assemblies stacked such that their long sides are adjacent to each other and housed in housing 51, and the number of electrode assemblies is not limited in this disclosure. Electrode assembly 40 can have a first electrode plate and a second electrode plate, the first electrode plate serving as a negative electrode and the second electrode plate serving as a positive electrode, and vice versa.

[0068] The first electrode plate can be formed by coating a first electrode active material, such as graphite or carbon, onto a first electrode current collector plate made of a metal foil, such as copper, a copper alloy, nickel, or a nickel alloy. The first electrode plate may include a first electrode tab (or first uncoated portion) 43, which is a region where the first electrode active material is not coated. The first electrode tab 43 can serve as a current flow channel between the first electrode plate and the first current collector portion 41. In some examples, the first electrode tab 43 may be formed in advance during the manufacture of the first electrode plate by cutting the first electrode plate to protrude to one side, or it may protrude to one side further than the diaphragm without separate cutting.

[0069] The second electrode plate can be formed by coating a second electrode active material, such as a transition metal oxide, onto a substrate made of a metal foil such as aluminum or an aluminum alloy. The second electrode plate may include a second electrode tab (or second uncoated portion) 44, which serves as a region uncoated by the second electrode active material. The second electrode tab 44 can function as a current flow channel between the second electrode plate and the second current collector 42. In some examples, the second electrode tab 44 may be formed in advance during the manufacture of the second electrode plate by cutting the second electrode plate to protrude towards the other side, or it may protrude further towards the other side than the diaphragm without separate cutting.

[0070] In some embodiments, the first electrode contact 43 may be located on the right end of the electrode assembly 40, and the second electrode contact 44 may be located on the left end of the electrode assembly 40. Alternatively, the first electrode contact 43 and the second electrode contact 44 may be located on one end of the electrode assembly 40 in the same direction. Here, for ease of explanation, left and right are represented based on the secondary battery illustrated in FIG1, and the positions of left and right may change when the secondary battery is rotated left and right or up and down.

[0071] The separator is used to prevent short circuits between the first and second electrode plates and to allow lithium ions to migrate between them. For example, the separator can be made of polyethylene membrane, polypropylene membrane, or polyethylene-polypropylene membrane.

[0072] The first electrode tab 43 of the first electrode plate and the second electrode tab 44 of the second electrode plate extend from both ends of the electrode assembly 40 as described herein. In some embodiments, the electrode assembly 40 may be housed together with the electrolyte in a housing 51.

[0073] In the electrode assembly 40, the first current collector 41 and the second current collector 42 can be welded and connected to the first electrode terminal 43 extending from the first electrode plate and the second electrode terminal 44 extending from the second electrode plate, respectively.

[0074] For reference Figure 1A The first current collector 41 and the second current collector 42 are respectively connected to the first terminal 62 and the second terminal 63 via terminal pins 67. In some embodiments, the terminal pins 67 may each have a threaded outer peripheral surface and can be fastened to the first terminal 62 and the second terminal 63 by threaded connection. However, this disclosure is not limited thereto. For example, the terminal pins 67 may also be connected to the first terminal 62 and the second terminal 63 by riveting or welding.

[0075] Figure 2 This is a schematic diagram illustrating an apparatus for heat sealing and stacking of diaphragms according to an embodiment of the present disclosure.

[0076] refer to Figure 2The apparatus 100 for heat sealing and stacking of diaphragms according to embodiments of the present disclosure may include a continuous diaphragm supply unit 110, a heat sealing unit 120, an electrode plate insertion unit 130, a cutting unit 140, and a stacking unit 150.

[0077] The apparatus 100 for heat sealing and stacking diaphragms according to embodiments of the present disclosure can stack rolled diaphragms and individual electrode plates.

[0078] The continuous diaphragm supply unit 110 may include multiple diaphragm rollers and supply diaphragms 11 in the form of continuous sheets.

[0079] The heat sealing unit 120 can heat seal two diaphragms 11 supplied from the continuous diaphragm supply unit 110.

[0080] The electrode plate insertion unit 130 can insert each electrode plate 21 and 22 between two heat-sealed diaphragms 11.

[0081] The cutting unit 140 can cut the two diaphragms 11 that are inserted between each of the electrode plates 21 and 22, thereby producing the unit group 30.

[0082] Stacking unit 150 can receive and stack the produced unit group 30 while aligning the manufactured unit group 30.

[0083] In the following text, a detailed configuration of the apparatus for diaphragm heat sealing and stacking according to embodiments of the present disclosure will be provided with reference to Figures 3 to 5 describe.

[0084] Figure 3 This is a view of a continuous diaphragm supply unit illustrating an apparatus for diaphragm heat sealing and stacking according to an embodiment of the present disclosure.

[0085] refer to Figure 3 The continuous diaphragm supply unit 110 may include a plurality of diaphragm rollers 111 and a roller unit 112 for supplying diaphragms 11 in the form of continuous sheets from the plurality of diaphragm rollers 111, and may also include a conveyor belt 113 for simultaneously receiving diaphragms 11 from the roller unit 112 and conveying the diaphragms 11 at the same speed. In an embodiment, the roller unit 112 may include two rollers and may receive diaphragms 11 from two diaphragm rollers 111 and supply the diaphragms 11 to a heat sealing unit 120 as a subsequent device via the conveyor belt 113.

[0086] Figure 4A This is a view of a heat-sealing unit illustrating an apparatus for heat-sealing and stacking diaphragms according to an embodiment of the present disclosure, and Figure 4B This is a view illustrating a diaphragm sealed by a heat-sealing unit of an apparatus for heat-sealing and stacking diaphragms according to an embodiment of the present disclosure.

[0087] refer to Figure 4A The heat sealing unit 120 can heat seal two diaphragms 11 supplied from the continuous diaphragm supply unit 110, and may include a silicone rubber part 121, a heat sealing strip 122, and a sealing motor 123.

[0088] In one embodiment, a heat-sealing strip 122 may be provided on one side of the silicone rubber portion 121 to form a heat-sealing area on the two diaphragms 11. A sealing motor 123 may move the silicone rubber portion 121 and the heat-sealing strip 122 upwards or downwards.

[0089] In addition, the heat sealing unit 120 may include a control circuit (not shown) that controls the voltage or current supplied to the heat sealing strip 122, and may apply high-temperature heat to the heat sealing strip 22 instantaneously by transmitting a pulse current to the heat sealing strip 122 using the Joule heating principle, thereby melting the thermoplastic polymer component in the diaphragm 11.

[0090] Furthermore, the silicone rubber portion 121 and the heat seal 122 can provide uniform pressure to the diaphragm. The heat seal 122 can be coated with Teflon material to prevent adhesion between the diaphragm 11 and the heat seal 122.

[0091] Subsequently, as the pulse current signal ends and cooling begins, the molten thermoplastic polymer components of the diaphragm 11 can be fused together to allow the two diaphragms to be bonded into a single layer.

[0092] Here, during the cooling process, pressure can be applied to the heat-sealing strip 122 and the silicone rubber portion 121 to perform cooling via conduction. Cooling can be performed in a short time of 1 second or less, thereby achieving ultrafast diaphragm heat sealing.

[0093] In an embodiment, the heat-sealing unit 120 may include a first heat-sealing unit 120-1 and a second heat-sealing unit 120-2 that are continuously positioned and each equipped with a heat-sealing strip 122 located in a different region. Figure 4B As illustrated, a first heat-sealing unit 120-1 can form a first heat-sealing area 12 on one side of the two diaphragms 11, and a second heat-sealing unit 120-2 can form a second heat-sealing area 13 on the opposite sides of the two diaphragms. Therefore, in the heat-sealing unit 120, the first heat-sealing unit 120-1 and the second heat-sealing unit 120-2, each having heat-sealing strips 122 located in different regions, are provided continuously, thereby allowing the continuously sealed diaphragms 11 to have heat-sealing areas in different regions. In other words, the heat-sealing unit 120 applied to two diaphragms 11 continuously supplied on the conveyor belt 113 can selectively heat-seal specific portions of the two diaphragms. The heat-sealing areas formed by the above process can be used as physical guide lines for subsequent alignment.

[0094] In an embodiment, by setting the heat-sealing strip 122 of the first heat-sealing unit 120-1 and the heat-sealing strip 122 of the second heat-sealing unit 120-2 to different sizes, the first heat-sealing area 12 and the second heat-sealing area 13 can be formed to be different from each other. Accordingly, for negative electrode plates and positive electrode plates with different sizes, the advantage that can be provided is that multiple materials with different sizes can be precisely aligned using guide lines with different sizes to align the corresponding electrode plates.

[0095] Referring back to Figure 1, the electrode plate insertion unit 130 can insert the first electrode plate 21 into the first heat-sealing region 12 and the second electrode plate 22 into the second heat-sealing region 13. In an embodiment, the first electrode plate 21 and the second electrode plate 22 can be inserted in opposite directions and can be aligned during insertion by contacting the first heat-sealing region 12 and the second heat-sealing region 13, respectively. Here, the first electrode plate 21 and the second electrode plate 22 can have opposite polarities. For example, the first electrode plate 21 can be a positive electrode plate, and the second electrode plate 22 can be a negative electrode plate.

[0096] Furthermore, the electrode plate insertion unit 130 can push the first electrode plate 21 and the second electrode plate 22 into the first heat-sealed area 12 and the second heat-sealed area 13, which serve as guide lines formed by the heat sealing of the diaphragm 11. In this case, to prevent damage to the heat-sealed areas 12 and 13 of the diaphragm 11, a force less than the bonding strength should be used for insertion. At the same time, a force should be applied to make the first electrode plate 21 and the second electrode plate 22 contact the first heat-sealed area 12 and the second heat-sealed area 13, respectively, to ensure precise alignment.

[0097] As described herein, the first heat-sealing region 12 and the second heat-sealing region 13 can be formed with different sizes by the heat-sealing unit 120. Accordingly, for the first electrode plate 21 and the second electrode plate 22 with different sizes, guide lines with different sizes can be used to align the corresponding electrode plates, thereby achieving precise alignment of materials of different sizes.

[0098] Figure 5 This is a view of a cutting unit illustrating an apparatus for heat sealing and stacking diaphragms according to an embodiment of the present disclosure.

[0099] refer to Figure 5The cutting unit 140 can cut two diaphragms 11 inserted between electrode plates to produce unit groups 30. The cutting unit 140 can also cut two diaphragms 11 inserted between each of continuously supplied electrode plates to produce individual unit groups 30, each having a diaphragm-electrode-plate configuration. In an embodiment, the cutting unit 140 may include a cutter 141 and a cutting motor 142, the cutter 141 being configured to cut two diaphragms 11 inserted between electrode plates, and the cutting motor 142 being configured to move the cutter 141 upwards or downwards.

[0100] Figure 6 This is a view of stacked units used to describe an apparatus for heat sealing and stacking diaphragms according to embodiments of the present disclosure.

[0101] refer to Figure 6 The stacking unit 150 can receive and stack the produced unit groups 30 while aligning the produced unit groups 30. The stacking unit 150 can repeatedly stack the unit groups 30 produced by cutting two diaphragms 11 inserted between each of the electrode plates, thereby realizing the manufacture of the electrode assembly as the final product.

[0102] In an embodiment, the stacking unit 150 may include a stacking platform 151, a stop 152, and a stacking motor 153. The stacking platform 151 receives the produced unit groups 30 and tilts to allow each of the produced unit groups 30 to slide downward on the stacking platform 151. The stop 152 stops and aligns the downwardly sliding unit groups 30, and the stacking motor 153 moves the stacking platform 151 up or down.

[0103] The stacking unit 150 can place the supplied unit group 30 on the stacking platform 151, and the unit group 30 can automatically align itself by contacting the stop 152 under gravity. For this purpose, the stop 152 may have wing portions on opposite sides to match the height of the unit group 30. The stacking motor 153 can move the stacking platform 151 up or down, thus holding the stacking platform 151 in a position that minimizes damage to the unit group 30.

[0104] Figure 7 This is a view used to describe a method of aligning electrode plates using means for heat sealing and stacking diaphragms according to embodiments of the present disclosure.

[0105] refer to Figure 7 According to embodiments of the present disclosure, by using the apparatus 100 for heat sealing and stacking the diaphragm 11 to heat seal the first heat-sealing area 12 and the second heat-sealing area 13, the electrode plates can be automatically aligned through physical contact with the sealing portion.

[0106] As described herein, the first heat-sealing region 12 and the second heat-sealing region 13 can be formed with different sizes by the heat-sealing unit 120. Accordingly, for the first electrode plate 21 and the second electrode plate 22 with different sizes, guide lines with different sizes can be used to align the corresponding electrode plates, thereby achieving precise alignment of materials of different sizes.

[0107] like Figure 7 As illustrated, when "d_cathode" represents the width of the heat-sealed area of ​​the diaphragm where the negative electrode plate is inserted, "w_cathode" represents the width of the negative electrode plate, and "w_separator" represents the width of the diaphragm, "w_separator" can be set to satisfy "d_cathode + w_cathode + d_cathode = w_separator". Similarly, when "d_anode" represents the width of the heat-sealed area of ​​the diaphragm where the positive electrode plate is inserted, "w_anode" represents the width of the positive electrode plate, and "w_separator" represents the width of the diaphragm, "w_separator" can be set to satisfy "d_anode + w_anode + d_anode = w_separator".

[0108] Ultimately, the advantage lies in the alignment of the negative and positive electrode plates at the center of the diaphragm, achieving the same alignment not only in the width direction but also in the height direction. Furthermore, by setting "d_cathode" and "d_anode" to different sizes, positive and negative electrode plates of different dimensions can be automatically and precisely aligned.

[0109] Figure 8 This is a flowchart describing a method for heat sealing and stacking diaphragms according to embodiments of the present disclosure.

[0110] See Figure 8 The method for heat sealing and stacking of diaphragms according to embodiments of the present disclosure may include steps S210 to S250.

[0111] Step S210 may be a step of supplying a diaphragm in the form of a continuous sheet through a continuous diaphragm supply unit. In an embodiment, step S210 may include a step of supplying a diaphragm in the form of a continuous sheet through a roller unit and a step of simultaneously receiving the diaphragm from the roller unit via a conveyor belt and conveying the diaphragm at the same speed.

[0112] Step S220 may be a step of heat-sealing two diaphragms supplied from a continuous diaphragm supply unit using a heat-sealing unit. In an embodiment, step S220 may include providing a heat-sealing unit (which includes a silicone rubber portion, a heat-sealing strip provided on one side of the silicone rubber portion, and a sealing motor configured to move the silicone rubber portion and the heat-sealing strip upward or downward) and applying uniform pressure to the diaphragms through the silicone rubber portion and the heat-sealing strip while forming heat-sealed areas on the two diaphragms through the heat-sealing strip. Furthermore, in an embodiment, step S220 may include providing a heat-sealing unit (which includes a first heat-sealing unit and a second heat-sealing unit positioned continuously to each other and each equipped with a heat-sealing strip in a different region), forming a first heat-sealed area on one side of the two diaphragms through the first heat-sealing unit, and forming a second heat-sealed area on opposite sides of the two diaphragms through the second heat-sealing unit.

[0113] Step S230 may be a step of inserting an electrode plate between two heat-sealed diaphragms using an electrode plate insertion unit. In an embodiment, step S230 may include inserting a first electrode plate into a first heat-sealed region and inserting a second electrode plate into a second heat-sealed region. Furthermore, in an embodiment, step S230 may include inserting the first and second electrode plates in opposite directions and aligning the first and second electrode plates during insertion by contacting the first and second heat-sealed regions.

[0114] Step S240 may be a step of producing a unit group by cutting two diaphragms inserted between each of the electrode plates using a cutting unit. In an embodiment, step S240 may include providing a cutter configured to cut two diaphragms inserted between each of the electrode plates and a cutting motor configured to move the cutter up or down.

[0115] Step S250 may be a step of receiving and stacking the produced cell groups 30 simultaneously by a stacking unit. In an embodiment, step S250 may include a step of providing a stacking unit including a stacking platform, a stop, and a stacking motor. The stacking platform receives the produced cell groups and tilts to allow each of the produced cell groups to slide downward on the stacking platform. The stop stops and aligns the sliding cell groups. The stacking motor moves the stacking platform up or down.

[0116] The method for heat-sealing and stacking diaphragms according to embodiments of the present disclosure has been described herein with reference to the flowcharts shown in the accompanying drawings. For brevity, the method has been illustrated and described as a series of blocks, but the present disclosure is not limited to the order of the blocks. In other words, some blocks may be performed simultaneously with other blocks, or in an order different from that illustrated and described herein, and various branches, flow paths, and block sequences that yield equivalent or similar results may also be implemented. Furthermore, not all blocks are required to implement the method described in the specification.

[0117] Reference Figure 8 In the description, based on embodiments of this disclosure, each step can be further divided into additional steps, or some steps can be combined into fewer steps. Furthermore, some steps can be omitted as needed, and the order of the steps can be changed. Additionally, although other descriptions are omitted, references... Figures 1A to 7 The given description can be used as a reference. Figure 8 The given description. Additionally, see references. Figure 8 The provided description can be used as a reference. Figures 1A to 7 The description provided.

[0118] In the following, materials that can be used in secondary batteries according to embodiments of the present disclosure are described.

[0119] Compounds capable of reversibly inserting and deintercalating lithium (e.g., lithiation intercalation compounds) can be used as positive electrode active materials. Specifically, one or more composite oxides of lithium selected from metals selected from cobalt, manganese, nickel, and combinations thereof can be used as positive electrode active materials.

[0120] The composite oxide can be a lithium transition metal composite oxide. Detailed examples of composite oxides may include lithium nickel oxides, lithium cobalt oxides, lithium manganese oxides, lithium iron phosphate compounds, cobalt-free nickel manganese oxides, or combinations thereof.

[0121] For example, a compound represented by one of the following chemical formulas can be used. Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b- c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-g G g PO4 (0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3 (0≤f≤2); and Li a FePO4 (0.90≤a≤1.8).

[0122] In the above chemical formulas: A can be Ni, Co, Mn, or a combination thereof; X can be Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, or a combination thereof; D can be O, F, S, P, or a combination thereof; G can be Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; and L 1 It can be Mn, Al, or a combination thereof.

[0123] The positive electrode for a lithium secondary battery may include a current collector and a layer of positive electrode active material formed on the current collector. The positive electrode active material layer may include a positive electrode active material and may further include a binder and / or a conductive material.

[0124] With respect to 100 wt.% of the positive electrode active material layer, the content of the positive electrode active material can be 90 wt.% to 99.5 wt.%. With respect to 100 wt.% of the positive electrode active material layer, the contents of the binder and the conductive material can be 0.5 wt.% to 5 wt.%.

[0125] Al can be used as the current collector, but the present disclosure is not limited thereto.

[0126] The negative electrode active material can include a material capable of reversibly inserting / extracting lithium ions, lithium metal, lithium metal alloy, a material capable of doping and dedoping lithium, or a transition metal oxide.

[0127] Materials capable of reversibly inserting / extracting lithium ions can include carbon-based negative electrode active materials, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon can include graphite, such as natural graphite or synthetic graphite. Examples of amorphous carbon can include soft carbon, hard carbon, mesophase pitch carbide, and sintered coke.

[0128] Si-based negative electrode active materials or Sn-based negative electrode active materials can be used as materials capable of doping and dedoping lithium. The Si-based negative electrode active material can be silicon, a silicon-carbon composite, SiO x (0 < x < 2), a Si-based alloy, or a combination thereof.

[0129] The silicon-carbon composite can be a composite of silicon and amorphous carbon. According to an example of an embodiment, the silicon-carbon composite can include silicon particles and can have a form in which amorphous carbon has been coated on the surface of the silicon particles.

[0130] The silicon-carbon composite can further include crystalline carbon. For example, the silicon-carbon composite can include a core containing crystalline carbon and silicon particles and an amorphous carbon coating provided on the surface of the core.

[0131] The negative electrode for a lithium secondary battery can include a current collector and a negative electrode active material layer provided on the current collector. The negative electrode active material layer can include a negative electrode active material and can further include a binder and / or a conductive material.

[0132] For example, the negative electrode active material layer can include 90 wt.% to 99 wt.% of the negative electrode active material, 0.5 wt.% to 5 wt.% of the binder, and 0 wt.% to 5 wt.% of the conductive material.

[0133] A non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof can be used as the binder. If an aqueous binder is used as the binder for the negative electrode, the binder for the negative electrode can further include a cellulose-based compound capable of imparting viscosity.

[0134] A current collector selected from nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, polymer matrix coated with conductive metal, and combinations thereof, can be used as a negative electrode.

[0135] Electrolytes used in lithium secondary batteries may include non-aqueous organic solvents and lithium salts.

[0136] Non-aqueous organic solvents can act as a medium through which ions participating in the electrochemical reactions of the battery can move.

[0137] Non-aqueous organic solvents can be carbonates, esters, ethers, ketones, or alcohols, aprotic solvents, or combinations thereof. Carbonates, esters, ethers, ketones, or alcohols, or aprotic solvents, can be used alone, or two or more of them can be mixed and used as non-aqueous organic solvents.

[0138] In addition, if carbonate solvents are used, mixtures of cyclic carbonates and chain carbonates can be mixed and used.

[0139] Depending on the type of lithium-ion secondary battery, a separator may be present between the positive and negative electrodes. Polyethylene, polypropylene, and polyvinylidene fluoride, or multilayers having two or more of these layers, can be used as separators.

[0140] The membrane may include a porous substrate and a coating comprising organic, inorganic or a combination thereof disposed on one or two surfaces of the porous substrate.

[0141] Organic substances may include polyvinylidene fluoride heavy antibodies or (meth)acrylate polymers.

[0142] Inorganic substances may include inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite and combinations thereof, but this disclosure is not limited thereto.

[0143] Organic and inorganic substances can be in the form of organic and inorganic substances being mixed in a coating or in the form of a coating including organic substances and a coating including inorganic substances being stacked.

Claims

1. An apparatus for heat sealing and stacking diaphragms, comprising: A continuous diaphragm supply unit is configured to supply diaphragms in the form of continuous sheets; A heat-sealing unit is configured to heat-seal two diaphragms supplied from the continuous diaphragm supply unit; An electrode plate insertion unit is configured to insert an electrode plate between the two heat-sealed diaphragms; as well as A cutting unit is configured to cut the two diaphragms inserted between the electrode plates to produce a unit assembly.

2. The apparatus according to claim 1, wherein the continuous diaphragm supply unit comprises: Roller units are configured to supply the diaphragm in the form of the continuous sheet; as well as A conveyor belt is configured to simultaneously receive the two diaphragms from the roller unit and transport the two diaphragms at the same speed.

3. The apparatus according to claim 1, wherein the heat sealing unit comprises: Silicone rubber part; A heat-sealing strip is provided on one side of the silicone rubber portion to form a heat-sealing area on the two diaphragms; as well as A sealing motor is configured to move the silicone rubber portion and the heat-sealing strip upwards or downwards.

4. The apparatus according to claim 3, The heat-sealing unit includes a first heat-sealing unit and a second heat-sealing unit, which are positioned sequentially and each has the heat-sealing strip in different regions. The first heat-sealing unit is configured to form a first heat-sealing area on one side of the two diaphragms, and The second heat-sealing unit is configured to form a second heat-sealing zone on the other side of the two diaphragms.

5. The apparatus of claim 3, wherein the heat seal is coated with a Teflon material to prevent adhesion between the diaphragm and the heat seal.

6. The apparatus of claim 4, wherein the electrode plate insertion unit is configured to insert a first electrode plate into the first heat-sealing region and to insert a second electrode plate into the second heat-sealing region.

7. The apparatus of claim 6, wherein the first electrode plate and the second electrode plate are inserted in opposite directions and are aligned during insertion by contacting the first heat-sealing region and the second heat-sealing region, respectively.

8. The apparatus according to claim 1, wherein the cutting unit comprises: A cutter is configured to cut the two diaphragms inserted between the electrode plates; as well as A cutting motor is configured to move the cutter up or down.

9. The apparatus of claim 1, further comprising a stacking unit configured to receive and stack the produced unit groups while aligning the produced unit groups.

10. The apparatus of claim 9, wherein the stacking unit comprises: A stacking platform is configured to receive the produced cell groups and tilted to allow the cell groups to slide downwards; A stop is configured to stop and align the downward sliding unit group; as well as A stacking motor is configured to move the stacking platform up or down.

11. A method for heat-sealing and stacking diaphragms, comprising: A diaphragm in continuous sheet form is supplied via a continuous diaphragm supply unit; The two diaphragms supplied from the continuous diaphragm supply unit are heat-sealed by the heat-sealing unit; The electrode plate is inserted between the two heat-sealed diaphragms using the electrode plate insertion unit; and The two diaphragms inserted between the electrode plates are cut by a cutting unit to produce a unit assembly.

12. The method of claim 11, wherein the supply of the diaphragm comprises: The diaphragm, in the form of a continuous sheet, is supplied through the roller unit of the continuous diaphragm supply unit; and The two diaphragms are simultaneously received from the roller unit via the conveyor belt of the continuous diaphragm supply unit and are conveyed at the same speed.

13. The method according to claim 11, The heat sealing unit includes: Silicone rubber part; A heat-sealing strip is provided on one side of the silicone rubber portion; and sealed motor; and The heat sealing process includes: moving the silicone rubber portion and the heat sealing strip upward or downward using the sealing motor, and forming a heat sealing area on the two diaphragms using the heat sealing strip.

14. The method according to claim 13, The heat sealing unit includes a first heat sealing unit and a second heat sealing unit, the first heat sealing unit and the second heat sealing unit being positioned sequentially and each having the heat sealing strip in different regions; and The heat seal includes: The first heat-sealing unit forms a first heat-sealing area on one side of the two diaphragms; and A second heat-sealing zone is formed on the other side of the two diaphragms by the second heat-sealing unit.

15. The method of claim 13, further comprising coating the heat seal with a Teflon material to prevent adhesion between the diaphragm and the heat seal.

16. The method of claim 14, wherein the insertion of the electrode plate comprises: Insert the first electrode plate into the first heat-sealing area; and Insert the second electrode plate into the second heat-sealing area.

17. The method of claim 16, wherein the insertion of the first electrode plate and the second electrode plate comprises inserting the first electrode plate and the second electrode plate in opposite directions, and aligning the first electrode plate and the second electrode plate during insertion by contacting the first heat-sealing region and the second heat-sealing region, respectively.

18. The method of claim 11, wherein the cutting unit comprises a cutter and a cutting motor; and The production of the unit group includes: The cutting motor moves the cutter up or down, and the cutter cuts the two diaphragms inserted between the electrode plates.

19. The method of claim 11, further comprising receiving and stacking the produced cell groups via a stacking unit, while aligning the produced cell groups.

20. The method of claim 19, wherein the stacking unit comprises: A stacking platform is configured to receive the produced cell groups and tilted to allow the cell groups to slide downwards; A stop is configured to stop and align the downward sliding unit group; And stacked motors, and The receiving and stacking of the unit group includes moving the stacking platform up or down via the stacking motor.

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