Electrode plate laminating device, bare cell winding apparatus, and bare cell winding method

Abstract

Disclosed in the present application are an electrode plate laminating device (100), a bare cell winding apparatus, and a bare cell winding method. The electrode plate laminating device (100) comprises: a first laminating roller assembly (20), which comprises a first laminating roller (21) and a second laminating roller (22), the first laminating roller (21) and the second laminating roller (22) being arranged directly opposite each other, and the first laminating roller (21) and the second laminating roller (22) being configured to sequentially stack and laminate a first separator (11), a first electrode plate (12) and a second separator (13) together; and a side separator laminating assembly (30), which is configured to laminate the part of the first separator (11) extending beyond a side edge of the first electrode plate (12) with the part of the second separator (13) extending beyond the side edge of the first electrode plate (12). By applying the technical solution provided by the embodiments of the present application, the problem of the first electrode plate and a second electrode plate overlapping each other due to the fact that the separators are prone to being folded in the winding process during preparation of the bare cell by the first separator, the first electrode plate, the second separator and the second electrode plate is solved.

Description

Pole piece composite device, bare cell winding equipment and bare cell winding method

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 28, 2023, with application number 202311279469.9 and invention name “Pole piece composite device, bare cell winding equipment and bare cell winding method”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery manufacturing technology, and in particular to a pole piece composite device, a bare cell winding device, and a bare cell winding method. Background Art

[0003] In the related art, a first electrode sheet and a separator are laminated together using a laminating roller to form a first composite strip, with the separator's edge regions extending beyond the first electrode sheet's sides. A second electrode sheet and another separator are also laminated together using a laminating roller to form a second composite strip, with the separator's edge regions extending beyond the second electrode sheet's sides. The first and second composite strips are then stacked and passed through a winding mechanism to form a bare cell.

[0004] Since there is no restrictive structure between the edge of the diaphragm extending beyond the side of the first pole piece and the edge of the diaphragm extending beyond the side of the second pole piece, during the process of winding the first composite material strip and the second composite material strip, the edge of the diaphragm extending beyond the side of the first pole piece and the edge of the diaphragm extending beyond the side of the second pole piece are prone to opening away from each other. Subsequently, under the action of external force, the edge of the diaphragm extending beyond the side of the first pole piece and / or the edge of the diaphragm extending beyond the side of the second pole piece are prone to folding, resulting in overlapping of the first pole piece and the second pole piece in the wound bare cell, causing the positive second pole piece to short-circuit. If such a bare cell is further assembled into a battery through subsequent manufacturing processes, it will cause a low voltage problem in the battery, affecting the product yield of the battery.

[0005] Summary of the Invention

[0006] The purpose of the embodiments of the present application is to provide a pole piece composite device, a bare cell winding device and a bare cell winding method, including but not limited to solving the problem that the first diaphragm, the first pole piece, the second diaphragm and the second pole piece are prone to folding during the winding process of preparing the bare cell, resulting in overlapping of the first pole piece and the second pole piece.

[0007] The technical solution adopted in the embodiment of this application is:

[0008] In a first aspect, a pole piece composite device is provided, comprising:

[0009] A first composite roller assembly includes a first composite roller and a second composite roller, the first composite roller and the second composite roller are arranged opposite to each other, and the first composite roller and the second composite roller are used to laminate the first diaphragm, the first electrode piece and the second diaphragm together in sequence;

[0010] The side diaphragm composite component is used to composite the portion of the first diaphragm that extends beyond the side of the first pole piece with the portion of the second diaphragm that extends beyond the side of the first pole piece.

[0011] The electrode assembly device provided in the embodiment of the present application performs a composite operation on the first diaphragm, the first electrode piece, and the second diaphragm. Not only is the first diaphragm, the first electrode piece, and the second diaphragm composited together by the first composite roller assembly, but also, through the side diaphragm composite assembly, the edge region of the first diaphragm extending beyond one side of the first electrode piece is composited with the edge region of the second diaphragm, and the edge region of the first diaphragm extending beyond the other side of the first electrode piece is composited with the edge region of the second diaphragm, thereby obtaining a composite strip in which the first diaphragm and the second diaphragm wrap around the first electrode piece. In this way, when the composite strip is used in subsequent processes including but not limited to the winding process and other processes after winding, the problem of the first diaphragm and / or the second diaphragm loosening from the first electrode piece and causing the diaphragm to fold can be avoided, and the situation of the first electrode piece and the second electrode piece overlapping can be eliminated. The first electrode piece and the second electrode piece are well insulated and separated by the first diaphragm or the second diaphragm, and the problem of low voltage in the battery caused by the overlapping of the first electrode piece and the second electrode piece can be eliminated, which helps to improve the product yield of the battery.

[0012] In the electrode composite device of some embodiments of the present application, the side diaphragm composite assembly includes a first side roller and a second side roller, the first side roller corresponds to the first side of the first electrode without a pole ear, and the second side roller corresponds to the second side of the first electrode with a pole ear, the first side roller is used to roll and composite the portions of the first and second diaphragms that extend beyond the first side together, and the second side roller is used to roll and composite the portions of the first and second diaphragms that extend beyond the second side together. In this way, in the composite material strip obtained by performing the composite operation, the first and second diaphragms wrap around the first electrode, and when the composite material strip is wound in the subsequent winding process, the edge areas of the first and second diaphragms that extend beyond the two sides of the first electrode will not overlap the first and second electrode pieces due to folding of the diaphragms even under the action of external force.

[0013] In the pole piece composite device of some embodiments of the present application, the first side roller and / or the second side roller includes a first gear roller and a load-bearing portion, and the first gear roller and the load-bearing portion are arranged relative to each other. In the pole piece composite device of some embodiments of the present application, the load-bearing portion is configured as a second gear roller, and the first gear roller and the second gear roller rotate synchronously. During the rotation of the two, the convex teeth of the first gear roller and the convex teeth of the second gear roller squeeze the first diaphragm and the second diaphragm in a one-to-one correspondence. In the pole piece composite device of some embodiments of the present application, when the second side roller includes the first gear roller, the tooth pitch between two adjacent convex teeth in the first gear roller is greater than or equal to the width of the pole lug, and the convex teeth of the first gear roller are used to roll and composite the first diaphragm and the second diaphragm located between two adjacent pole lugs. The edge area of ​​the first diaphragm and the edge area of ​​the second diaphragm are composited together by the first gear roller and the load-bearing part, and the first diaphragm and the second diaphragm are composited through multiple spaced connection positions. In the manufactured battery, when the bare battery cell is immersed in the electrolyte, the electrolyte can penetrate through the gap between the first diaphragm and the second diaphragm without composite adhesion, thereby quickly infiltrating the first electrode piece and the second electrode piece, thereby improving the electrolyte infiltration efficiency.

[0014] In the electrode composite device of some embodiments of the present application, the side diaphragm composite assembly may be additionally provided with a gluing mechanism, the first side roller and / or the second side roller includes a first circular roller and a load-bearing portion, the first circular roller and the load-bearing portion are arranged relative to each other, the gluing mechanism is located upstream of the first circular roller, and the gluing mechanism is used to apply glue between the first diaphragm and the second diaphragm portions extending beyond the side of the first electrode. In the electrode composite device of some embodiments of the present application, the load-bearing portion is arranged as a second circular roller, and the second circular roller rotates synchronously with the first circular roller. Glue is applied between the first diaphragm and the second diaphragm extending beyond the side of the first electrode by the gluing mechanism, and then the edge area of ​​the first diaphragm and the edge area of ​​the second diaphragm extending beyond the side of the first electrode are continuously rolled by the first circular roller and the load-bearing portion, so that the edge area of ​​the first diaphragm and the edge area of ​​the second diaphragm are quickly glued and composited together.

[0015] In some embodiments of the present application, the side diaphragm assembly of the electrode assembly can be equipped with an additional UV lamp located downstream of the first circular roller. The UV lamp is used to illuminate the glue-coated areas of the first and second diaphragms. Illuminating the glue between the first and second diaphragms beyond the side of the first electrode assembly with the UV lamp helps increase the glue curing rate, thereby improving production efficiency.

[0016] In some embodiments of the electrode assembly device of the present application, the electrode assembly device further includes a first conveying roller, the first conveying roller being located upstream of and spaced apart from one of the first composite roller and the second composite roller, one of the first diaphragm and the second diaphragm being lapped around the first conveying roller to be conveyed obliquely between the first composite roller and the second composite roller; and / or the electrode assembly device further includes a second conveying roller, the second conveying roller being located upstream of and spaced apart from the other of the first composite roller and the second composite roller, the other of the first diaphragm and the second diaphragm being lapped around the second conveying roller to be conveyed obliquely between the first composite roller and the second composite roller. In this way, during the process of the first diaphragm, the first electrode sheet, and the second diaphragm being conveyed between the first composite roller and the second composite roller for stacking and performing the roll-pressing composite operation, the conveying paths of the first diaphragm, the first electrode sheet, and the second diaphragm do not interfere with each other, so that the first diaphragm, the first electrode sheet, and the second diaphragm can all be conveyed smoothly.

[0017] In some embodiments of the electrode assembly device of the present application, the electrode assembly device further includes a first cutting mechanism, the first cutting mechanism being located upstream of the first composite roller assembly and configured to cut the first electrode. In some embodiments of the electrode assembly device of the present application, the electrode assembly device further includes a first detection mechanism, the first detection mechanism being located between the first cutting mechanism and the first composite roller assembly, the first detection mechanism being electrically connected to the first cutting mechanism and configured to detect the conveying length of the first electrode. The first detection mechanism and the first cutting mechanism enable automatic cutting of the first electrode, thereby improving the degree of automation and production efficiency.

[0018] In a second aspect, a bare cell winding device is provided, comprising:

[0019] The aforementioned electrode composite device outputs a composite material strip formed by sequentially stacking and composited the first diaphragm, the first electrode and the second diaphragm;

[0020] A second composite roller assembly is located downstream of the electrode sheet composite device. The second composite roller assembly includes a third composite roller and a fourth composite roller. The third composite roller and the fourth composite roller are arranged opposite each other. The third composite roller and the fourth composite roller are used to composite the second electrode sheet onto one of the first diaphragm and the second diaphragm to output the battery core strip;

[0021] The winding mechanism is located downstream of the second composite roller assembly and is used to wind the battery core strip into a bare battery core.

[0022] In the bare cell winding device provided by the embodiment of the present application, the electrode composite device provided by the embodiment of the present application is used to perform a composite operation on the first diaphragm, the first electrode piece, and the second diaphragm. Not only are the first diaphragm, the first electrode piece, and the second diaphragm composited together by the first composite roller assembly, but also, through the operation of the side diaphragm composite assembly, the edge area of ​​the first diaphragm that exceeds one side of the first electrode piece is composited with the edge area of ​​the second diaphragm, and the edge area of ​​the first diaphragm that exceeds the other side of the first electrode piece is composited with the edge area of ​​the second diaphragm, thereby obtaining a composite material strip in which the first diaphragm and the second diaphragm wrap the first electrode piece. The second electrode piece is then rolled and composited on the first diaphragm or the second diaphragm of the composite material strip by the second composite roller assembly, and then a winding operation is performed to wind up a bare cell. In subsequent processes including but not limited to the winding process and other processes after winding, the problem of the first diaphragm and / or the second diaphragm loosening from the first electrode sheet, which may cause the diaphragm to fold, can be avoided, and the overlapping of the first electrode sheet and the second electrode sheet can be eliminated, thereby eliminating the overlapping of the first electrode sheet and the second electrode sheet in the wound bare battery cell, so that the first electrode sheet and the second electrode sheet are well insulated and separated by the first diaphragm or the second diaphragm, eliminating the problem of low voltage in the battery caused by the overlapping of the first electrode sheet and the second electrode sheet, and helping to improve the product yield of the battery.

[0023] In some embodiments of the present application, the bare cell winding apparatus further includes a second detection mechanism and a pressing mechanism. The second detection mechanism is located upstream of the second composite roller assembly and is electrically connected to the pressing mechanism. The pressing mechanism is used to press the end of the second pole piece against one of the first diaphragm and the second diaphragm. The cooperation between the second detection mechanism and the pressing mechanism allows the end of the second pole piece to be accurately and quickly pressed against the composite material strip, thereby accurately determining the center distance between the first pole tab of the first pole piece and the second pole tab of the second pole piece, thereby improving production efficiency.

[0024] In some embodiments of the present application, the bare cell winding apparatus further includes a second cutting mechanism, located upstream of the pressing mechanism and electrically connected to the second detection mechanism. The second cutting mechanism is configured to cut the second electrode sheet when the second detection mechanism detects a predetermined conveying length of the second electrode sheet. This improves the accuracy of cutting the second electrode sheet and enhances the product quality of the bare cell.

[0025] In some embodiments of the bare cell winding device of the present application, the bare cell winding device also includes a third conveying roller, which is located upstream of the second cutting mechanism. The second electrode sheet is wrapped around the third conveying roller so that the second electrode sheet is conveyed obliquely to the pressing mechanism, so that the second electrode sheet can always be conveyed smoothly, thereby improving production efficiency.

[0026] In the bare cell winding equipment of some embodiments of the present application, the bare cell winding equipment may be additionally provided with a film stripping guide roller, which is located downstream of the second composite roller assembly. The film stripping guide roller is used to peel off the release film of the electrostatic protective film composited with the second pole piece, thereby realizing a rapid peeling operation of the release film and improving production efficiency.

[0027] In a third aspect, a bare cell winding method is provided, comprising the following steps:

[0028] The first diaphragm, the first pole piece and the second diaphragm are laminated together in sequence;

[0029] Compounding the second electrode sheet on one of the first diaphragm and the second diaphragm to form a battery core strip;

[0030] The battery cell strip is wound to form a bare battery cell.

[0031] The bare cell winding method provided in the embodiment of the present application is used to wind and form a bare cell. Since the first diaphragm, the first electrode piece, the second diaphragm and the second electrode piece are compounded to form a cell strip through steps S10 and S20, and then the winding operation is performed, that is, the end of the cell strip formed by the first diaphragm, the first electrode piece, the second diaphragm and the second electrode piece is fixed on the winding mechanism at one time. Compared with the winding operation of the related technology, the problem of the second composite material strip swinging is eliminated, which not only greatly improves the winding work efficiency, but also improves the winding quality of the bare cell, and significantly improves the product yield of the bare cell.

[0032] In the bare cell winding method of some embodiments of the present application, before executing the step of "winding the cell material strip into a bare cell", the bare cell winding method further includes the steps of: compounding the first diaphragm that extends beyond one side of the first pole piece with the second diaphragm; compounding the first diaphragm that extends beyond the other side of the first pole piece with the second diaphragm. In this way, in subsequent processes including but not limited to the winding process and other processes after winding, the problem of the first diaphragm and / or the second diaphragm loosening from the first pole piece and causing the diaphragm to fold can be avoided, and the overlap of the first pole piece and the second pole piece can be eliminated, thereby eliminating the overlap of the first pole piece and the second pole piece in the wound bare cell, so that the first pole piece and the second pole piece are well insulated and separated by the first diaphragm or the second diaphragm, eliminating the problem of low voltage of the battery caused by the overlap of the first pole piece and the second pole piece, and helping to improve the product yield of the battery.

[0033] In some embodiments of the present application, in the bare cell winding method, when executing the step of "combining the first separator, the first electrode sheet, and the second separator in sequence in a stacked manner," the bare cell winding method further includes the steps of: detecting a first predetermined length of the first electrode sheet and cutting the first electrode sheet according to the first predetermined length; and, when executing the step of "combining the second electrode sheet on one of the first separator and the second separator to form a cell strip," the bare cell winding method further includes the steps of: detecting a second predetermined length of the second electrode sheet and cutting the second electrode sheet according to the second predetermined length. This greatly improves the automation process of winding bare cells and can significantly increase the production efficiency of bare cells.

[0034] In the bare cell winding method of some embodiments of the present application, the first predetermined length is greater than the second predetermined length, and both end ends of the cut first electrode sheet extend beyond both end ends of the second electrode sheet, thus meeting the standard requirement that the first electrode sheet in the production of bare cells is longer than the second electrode sheet.

[0035] In some embodiments of the present application, the bare cell winding method further includes, before performing the step of "combining the first separator, the first electrode piece, and the second separator in a sequentially stacked manner," the step of securing the end of the first electrode piece to one of the first separator and the second separator. Positioning the end of the first electrode piece reduces or even eliminates the frequency of offset of the first electrode piece relative to the first and second separators during the composite strip molding process, thereby improving both composite efficiency and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or exemplary technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0037] FIG1 is a schematic structural diagram of equipment for a compounding process and a winding process in the related art;

[0038] FIG2 is a schematic structural diagram of a device for a winding process in the related art;

[0039] FIG3 is a first structural diagram of a pole piece composite device according to an embodiment of the present application;

[0040] FIG4 is a second structural diagram of a pole piece composite device according to an embodiment of the present application;

[0041] FIG5 is a third structural diagram of a pole piece composite device according to an embodiment of the present application;

[0042] FIG6 is a fourth structural diagram of a pole piece composite device according to an embodiment of the present application;

[0043] FIG7 is a fifth structural diagram of a pole piece composite device according to an embodiment of the present application;

[0044] FIG8 is a sixth structural diagram of a pole piece composite device according to an embodiment of the present application;

[0045] FIG9 is a seventh structural diagram of a pole piece composite device according to an embodiment of the present application;

[0046] FIG10 is a structural schematic diagram eight of a pole piece composite device according to an embodiment of the present application;

[0047] FIG11 is a ninth structural diagram of a pole piece composite device according to an embodiment of the present application;

[0048] FIG12 is a schematic structural diagram of a bare cell winding device according to an embodiment of the present application;

[0049] FIG13 is a flowchart of a bare cell winding method according to an embodiment of the present application;

[0050] FIG14 is a second flow chart of the bare cell winding method according to an embodiment of the present application.

[0051] 1. The figures in the figure are as follows: 100, electrode assembly; 10, battery core strip; 11, first separator; 12, first electrode piece; 121, first electrode tab; 13, second separator; 14, composite strip; 15, second electrode piece; 16, release film; 20, first composite roller assembly; 21, first composite roller; 22, second composite roller; 30, side separator composite assembly; 31, side roller assembly; 311, first side roller; 312, second side roller; 313, first gear roller; 314, first convex tooth; 315, load-bearing portion; 316, second convex tooth; 317, first round roller; 32, gluing mechanism; 33, ultraviolet lamp; 41, first conveyor roller; 42, second conveyor roller; 43, third conveyor roller; 44, first cutting mechanism; 45, first detection mechanism; 50. Second composite roller assembly; 51. Third composite roller; 52. Fourth composite roller; 61. Winding mechanism; 62. Second detection mechanism; 63. Pressing mechanism; 64. Second cutting mechanism; 65. Demolding guide roller; 66. Positioning tape; 67. Positioning adhesive; 300. Composite roller; 301. First composite material strip; 302. Second composite material strip. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit this application.

[0053] It should be noted that when a component is referred to as being "fixed on" or "disposed on" another component, it may be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it may be directly or indirectly connected to the other component. The terms "upper", "lower", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of description and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this application. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances. The terms "first" and "second" are only used for the purpose of convenience of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. "Multiple" means two or more, unless otherwise clearly and specifically defined.

[0054] In order to illustrate the technical solution provided by this application, a detailed description is given below with reference to specific drawings and embodiments.

[0055] Currently, market developments indicate that the application of power batteries, particularly lithium batteries, is becoming increasingly widespread. Lithium batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric vehicles, as well as in police equipment, military equipment, and aerospace. As the application of lithium batteries continues to expand, market demand is also growing.

[0056] In the process of preparing lithium batteries, a series of processes are required, which include but are not limited to compounding process, winding process, shaping process, battery cell assembly process, welding process, etc. in the production order.

[0057] The composite process refers to compositely forming the first electrode sheet, the diaphragm and the second electrode sheet into a cell material strip for winding the bare cell.

[0058] The winding process refers to winding the composite-molded battery cell material strip to form a bare battery cell semi-finished product. At this time, the bare battery cell semi-finished product formed by winding is in a fluffy state, the shape outline of the bare battery cell is not fixed, and the first and second pole pieces in the bare battery cell are easy to slip and difficult to assemble.

[0059] The shaping process refers to the use of hot pressing or cold pressing to clamp and press the fluffy bare battery cell semi-finished products to fix the shape contour of the bare battery cell, thereby solving the problem that the first and second pole pieces in the fluffy bare battery cell are easy to slip and difficult to assemble, which is conducive to improving the assembly accuracy and efficiency of the subsequent battery cell assembly process.

[0060] The process of assembling battery cells refers to assembling the shaped bare cells, current collectors, shells, shell covers and other components into battery cells.

[0061] The welding process refers to welding components such as the shell, shell cover and electrode terminals so that the shell and shell cover are sealed and the electrode terminals are electrically connected to the bare battery cells.

[0062] In the related art, the compounding process and the winding process are generally combined and operated together. As shown in Figure 1, the first pole piece and a diaphragm are compounded together by a compounding roller 300 to form a first composite material strip 301, and the edge areas on both sides of the diaphragm exceed the side edges of the first pole piece; the second pole piece and another diaphragm are also compounded together by another compounding roller 300 to form a second composite material strip 302, and the edge areas on both sides of the diaphragm exceed the side edges of the second pole piece. Then, the first composite material strip 301 and the second composite material strip 302 are stacked and passed through the winding mechanism 61, so as to be wound into a bare battery cell. When the first composite material strip 301 and the second composite material strip 302 are stacked, the first pole piece and the second pole piece are insulated and separated by one of the diaphragms, and then the winding operation is performed. Since there is no restrictive structure between the edge of the diaphragm extending beyond the side of the first electrode piece and the edge of the diaphragm extending beyond the side of the second electrode piece, during the process of winding the first composite material strip 301 and the second composite material strip 302, the edge of the diaphragm extending beyond the side of the first electrode piece and the edge of the diaphragm extending beyond the side of the second electrode piece are prone to opening away from each other. Subsequently, when the diaphragm is wound around the roller, the diaphragm is prone to folding, resulting in the first electrode piece and the second electrode piece overlapping. That is to say, in the subsequent manufacturing process of the wound bare cell, the diaphragm is subjected to external forces (such as the force of air conditioning wind blowing, and the interference of the positioning block for correcting the deviation of the material strip, etc.), and the edge of the diaphragm extending beyond the side of the positive electrode piece and / or the edge of the diaphragm extending beyond the side of the negative electrode piece are prone to folding, resulting in the first electrode piece and the second electrode piece in the wound bare cell overlapping. If such a bare cell is assembled into a battery through subsequent manufacturing processes, it will cause the battery to have a low voltage problem, affecting the product yield of the battery.

[0063] Based on the above considerations, in order to solve the technical problems existing in the related art, namely: when compounding and winding the first pole piece, the second pole piece and the two diaphragms to form a bare cell, the edge of the diaphragm that exceeds the side of the first pole piece and / or the edge of the diaphragm that exceeds the side of the second pole piece is prone to folding, resulting in overlapping of the first pole piece and the second pole piece in the wound bare cell, resulting in low voltage problems in the assembled battery, therefore, the embodiment of the present application is designed to provide a pole piece compound device 100, a bare cell winding device and a bare cell winding method. The pole piece compound device 100, the bare cell winding device and the bare cell winding method provided in the embodiment of the present application are designed to compound the edge of the diaphragm that exceeds the side of the first pole piece and the edge of the diaphragm that exceeds the side of the second pole piece when compounding the first pole piece, the second pole piece and the two diaphragms, so that one of the first pole piece and the second pole piece is wrapped by the two diaphragms, and then the other of the first pole piece and the second pole piece is compounded on one of the diaphragms, and then wound to obtain a bare cell. In this way, during the process of winding the composite battery cell strip into a bare battery cell, the folding of the diaphragm edge beyond the side of the first pole piece and / or the diaphragm edge beyond the side of the second pole piece can be eliminated, so that the first pole piece and the second pole piece are well insulated and separated by the diaphragm, thereby eliminating the low voltage problem of the battery caused by the overlap of the first pole piece and the second pole piece, which helps to improve the product yield of the battery.

[0064] In the embodiment of the present application, the two diaphragms are a first diaphragm 11 and a second diaphragm 13. Furthermore, one of the first electrode piece and the second electrode piece is a first electrode piece 12, and the other of the first electrode piece and the second electrode piece is a second electrode piece 15. The following description assumes that the positive electrode piece is the first electrode piece 12 and the negative electrode piece is the second electrode piece 15.

[0065] As shown in Figures 3 and 4, the electrode sheet assembly device 100 provided in an embodiment of the present application includes a first composite roller assembly 20 and a side diaphragm composite assembly 30. The first composite roller assembly 20 includes a first composite roller 21 and a second composite roller 22. The first composite roller 21 and the second composite roller 22 are arranged opposite each other and rotate synchronously. The first composite roller 21 and the second composite roller 22 rotate in opposite directions. The first composite roller 21 and the second composite roller 22 are used to laminate the first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13 together in a stacked manner. That is, the first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13 are laminated in sequence and then rolled by the first composite roller 21 and the second composite roller 22, thereby laminating the first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13 together to form a composite strip 14. In the composite strip 14, the side edge regions of the first diaphragm 11 and the side edge regions of the second diaphragm 13 both extend beyond the side edges of the first electrode sheet 12. Then, the side diaphragm composite assembly 30 composites the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13 that extend beyond one side of the first electrode piece 12, and the side diaphragm composite assembly 30 composites the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13 that extend beyond the other side of the first electrode piece 12, so that the first diaphragm 11 and the second diaphragm 13 wrap around the first electrode piece 12. In this way, in subsequent processes including but not limited to the winding process and other processes after winding, the problem of the first diaphragm and / or the second diaphragm loosening from the first electrode piece and causing the diaphragm to fold can be avoided, and the overlap of the first and second electrode pieces can be eliminated.

[0066] The electrode composite device 100 provided in the embodiment of the present application performs a composite operation on the first diaphragm 11, the first electrode piece 12 and the second diaphragm 13. Not only are the first diaphragm 11, the first electrode piece 12 and the second diaphragm 13 composited together through the first composite roller assembly 20, but also, through the operation of the side diaphragm composite assembly 30, the edge area of ​​the first diaphragm 11 extending beyond one side of the first electrode piece 12 is composited with the edge area of ​​the second diaphragm 13, and the edge area of ​​the first diaphragm 11 extending beyond the other side of the first electrode piece 12 is composited with the edge area of ​​the second diaphragm 13, thereby obtaining a composite material strip 14 in which the first diaphragm 11 and the second diaphragm 13 wrap the first electrode piece 12. In this way, when the composite material strip 14 is wound in the subsequent winding process, the edge areas of the first diaphragm 11 and the second diaphragm 13 that extend beyond the two side edges of the first electrode sheet 12 are not easy to fold even under the action of external force, or even if they are folded, the first electrode sheet and the second electrode sheet will not be exposed, and the first electrode sheet and the second electrode sheet will not be overlapped, thereby eliminating the overlap of the first electrode sheet 12 and the second electrode sheet 15 in the wound bare battery cell, so that the first electrode sheet 12 and the second electrode sheet 15 are well insulated and separated by the first diaphragm 11 or the second diaphragm 13, eliminating the low voltage problem of the battery caused by the overlap of the first electrode sheet 12 and the second electrode sheet 15, and helping to improve the product yield of the battery.

[0067] In some embodiments of the present application, the side diaphragm composite assembly 30 may be located downstream of the first composite roller assembly 20. That is, after the first diaphragm 11, the first electrode piece 12, and the second diaphragm 13 are stacked in sequence, a rolling operation is first performed to composite the first diaphragm 11, the first electrode piece 12, and the second diaphragm 13 together, and then the edge areas of the first diaphragm 11 and the edge areas of the second diaphragm 13 that extend beyond the two sides of the first electrode piece 12 are composited.

[0068] Alternatively, in some other embodiments of the present application, the side diaphragm composite assembly 30 is located upstream of the first composite roller assembly 20. That is, after the first diaphragm 11, the first electrode piece 12, and the second diaphragm 13 are stacked in sequence, the edge areas of the first diaphragm 11 and the edge areas of the second diaphragm 13 that extend beyond the two sides of the first electrode piece 12 are composited first, and then a rolling operation is performed to composite the first diaphragm 11, the first electrode piece 12, and the second diaphragm 13 together.

[0069] In some embodiments of the present application, the first composite roller 21 and / or the second composite roller 22 are heated and then roll-pressed on the first diaphragm 11, the first pole piece 12, and the second diaphragm 13, i.e., hot pressing lamination. Alternatively, the first composite roller 21 and / or the second composite roller 22 are configured to transmit ultrasonic energy and ultrasonically roll-press the first diaphragm 11, the first pole piece 12, and the second diaphragm 13, i.e., ultrasonic lamination. Alternatively, the first composite roller 21 and / or the second composite roller 22 roll-press the first diaphragm 11, the first pole piece 12, and the second diaphragm 13 at room temperature, i.e., cold pressing lamination.

[0070] As shown in Figures 3 and 4, in some embodiments of the present application, the side diaphragm composite assembly 30 includes an edge roller assembly 31, which rolls the edge areas of the first diaphragm 11 and the edge areas of the second diaphragm 13 that extend beyond the two side edges of the first pole piece 12 respectively, thereby rolling the edge areas of the first diaphragm 11 and the second diaphragm 13 together.

[0071] As shown in Figures 3 and 4, in some embodiments of the present application, the edge roller assembly 31 includes a first edge roller 311, and the first edge roller 311 corresponds to the side of the first pole piece 12 where the pole tab is not provided. During the composite operation of the first diaphragm 11, the first pole piece 12, and the second diaphragm 13, the first edge roller 311 is used to roll and composite the first diaphragm 11 and the second diaphragm 13 that extend beyond the side of the first pole piece 12. In addition, the edge roller assembly 31 also includes a second edge roller 312, and the second edge roller 312 corresponds to the side of the first pole piece 12 where the pole tab is provided. During the composite operation of the first diaphragm 11, the first pole piece 12, and the second diaphragm 13, the second edge roller 312 is used to roll and composite the first diaphragm 11 and the second diaphragm 13 that extend beyond the side of the first pole piece 12. In this way, in the composite material strip 14 obtained after the composite operation is completed, the first diaphragm 11 and the second diaphragm 13 wrap the first electrode piece 12. When the composite material strip 14 is wound in the subsequent winding process, the edge areas of the first diaphragm 11 and the second diaphragm 13 that extend beyond the two side edges of the first electrode piece 12 are not easy to fold even under the action of external force, or even if they are folded, the first electrode piece and the second electrode piece will not be exposed, and the first electrode piece and the second electrode piece will not be overlapped.

[0072] As shown in Figures 3 to 5, in some embodiments of the present application, only the first side roller 311 includes a first gear roller 313 and a load-bearing portion 315, and the first gear roller 313 and the load-bearing portion 315 are arranged opposite each other. The load-bearing portion 315 supports the edge areas of the first diaphragm 11 and the second diaphragm 13 that extend beyond the side of the first pole piece 12. Then, the tooth tops of the first protruding teeth 314 of the first gear roller 313 press the edge areas of the first diaphragm 11 and the second diaphragm 13 against the load-bearing portion 315, thereby combining the edge areas of the first diaphragm 11 and the second diaphragm 13. At this time, the edge areas of the first diaphragm 11 and the second diaphragm 13 are discontinuous, and the first diaphragm 11 and the second diaphragm 13 are combined through multiple spaced connection locations. Moreover, there is a position without composite adhesion between two adjacent connection positions. In the manufactured battery, when the bare cell is immersed in the electrolyte, the electrolyte can penetrate through the gap between the first diaphragm 11 and the second diaphragm 13 without composite adhesion, thereby quickly infiltrating the first electrode 12 and the second electrode 15, thereby improving the electrolyte infiltration efficiency.

[0073] As shown in Figures 3 and 4, in some embodiments of the present application, only the second side roller 312 includes a first gear roller 313 and a load-bearing portion 315, with the first gear roller 313 and the load-bearing portion 315 disposed opposite each other. The load-bearing portion 315 supports the edge regions of the first diaphragm 11 and the second diaphragm 13 that extend beyond the side of the first electrode sheet 12, as well as each first electrode tab 121. The tooth tips of the first protruding teeth 314 then press the edge regions of the first diaphragm 11 and the second diaphragm 13 between two adjacent first electrode tabs 121 against the load-bearing portion 315, thereby combining the edge regions of the first diaphragm 11 and the second diaphragm 13. At this point, the edge regions of the first diaphragm 11 and the second diaphragm 13 corresponding to the first electrode tab 121 are not bonded to the first electrode tab 121, allowing electrolyte to pass through and wet the first and second electrode sheets 12 and 15, thereby improving electrolyte wetting efficiency.

[0074] As shown in Figures 3 to 5, in some embodiments of the present application, in order to further improve the wetting efficiency of the electrolyte in the first electrode piece 12 and the second electrode piece 15, the first side roller 311 and the second side roller 312 both include a first gear roller 313 and a load-bearing part 315.

[0075] In some embodiments of the present application, the load-bearing portion 315 can be configured as, but is not limited to, a second gear roller, a load-bearing workbench, or the like. When the load-bearing portion 315 is configured as a second gear roller, the first gear roller 313 and the second gear roller rotate synchronously, with the first gear roller 313 and the second gear roller rotating in opposite directions. Furthermore, the synchronous rotation of the first gear roller 313 and the second gear roller can provide a driving force for the composite strip 14 to move backward, thereby improving composite work efficiency. During the synchronous rotation of the first gear roller 313 and the second gear roller, the first protruding teeth 314 of the first gear roller 313 and the second protruding teeth 316 of the second gear roller correspond one-to-one to squeeze the first diaphragm 11 and the second diaphragm 13.

[0076] In some embodiments of the present application, the second side roller 312 includes a first gear roller 313, and the pitch between two adjacent first convex teeth 314 in the first gear roller 313 is greater than or equal to the width of the first pole tab 121 of the first pole piece 12. The first convex teeth 314 of the first gear roller 313 are used to roll and laminate the first diaphragm 11 and the second diaphragm 13 located between the two adjacent first pole tabs 121. Accordingly, when the load-bearing portion 315 is configured as a second gear roller, the pitch between two adjacent second convex teeth 316 in the second gear roller is greater than or equal to the width of the first pole tab 121 of the first pole piece 12. During the rotation of the first gear roller 313 and the second gear roller, the center of each first convex tooth 314 and the center of each second convex tooth 316 can be arranged in a one-to-one correspondence with each other. Because the pitch between two adjacent first protruding teeth 314 is greater than or equal to the width of the first pole tab 121 of the first pole piece 12, and the pitch between two adjacent second protruding teeth 316 is greater than or equal to the width of the first pole tab 121 of the first pole piece 12, the first protruding teeth 314 and the second protruding teeth 316 can avoid the first pole tabs 121 of the first pole piece 12, thereby avoiding squeezing the first pole tabs 121 and causing deformation or even breakage of the first pole tabs 121. Moreover, when the first protruding teeth 314 and the second protruding teeth 316 avoid the first pole tabs 121, the first diaphragm 11 and the second diaphragm 13 opposite the first pole tab 121 are not laminated to the first pole tab 121. That is, there is a gap between the first electrode tab 121 and the corresponding first diaphragm 11, and there is a gap between the first electrode tab 121 and the corresponding second diaphragm 13. In the manufactured battery, when the bare cell is immersed in the electrolyte, the electrolyte can penetrate through these gaps, thereby quickly infiltrating the first electrode sheet 12 and the second electrode sheet 15, thereby improving the electrolyte infiltration efficiency. Optionally, the pitch between two adjacent second protruding teeth 316 in the second gear roller is equal to the pitch between two adjacent first protruding teeth 314 in the first gear roller 313.

[0077] In some other embodiments of the present application, the width of the second teeth 316 is greater than the width of the first teeth 314, and the pitch between two adjacent second teeth 316 in the second gear roller is less than the pitch between two adjacent first teeth 314 in the first gear roller 313. Furthermore, during rotation of the first and second gear rollers, the centers of each first tooth 314 and each second tooth 316 can be aligned and aligned. In this manner, the first teeth 314 and the second teeth 316 not only roll-compound and composite-bond the first and second separators 11 and 13 between two adjacent first electrode tabs 121, but also increase the spacing between adjacent composite-bond locations compared to a situation where the pitch between two adjacent first teeth 314 is equal to the pitch between two adjacent second teeth 316, and the width of the first teeth 314 is equal to the width of the second teeth 316. This increases the spacing for electrolyte infiltration, allowing the electrolyte to quickly penetrate the first electrode sheet 12, thereby improving electrolyte infiltration efficiency.

[0078] Alternatively, in some other embodiments of the present application, the width of the second teeth 316 is smaller than the width of the first teeth 314, and the pitch between two adjacent second teeth 316 in the second gear roller is greater than the pitch between two adjacent first teeth 314 in the first gear roller 313. Furthermore, during rotation of the first and second gear rollers, the centers of each first tooth 314 and each second tooth 316 can be aligned and aligned. In this manner, the first teeth 314 and the second teeth 316 not only roll-compound and composite-bond the first and second separators 11 and 13 between two adjacent first electrode tabs 121, but also increase the spacing between adjacent composite-bond locations compared to a situation where the pitch between two adjacent first teeth 314 is equal to the pitch between two adjacent second teeth 316, and the width of the first teeth 314 is equal to the width of the second teeth 316. This increases the spacing opening for electrolyte infiltration, allowing the electrolyte to quickly infiltrate the first electrode sheet 12, thereby improving electrolyte infiltration efficiency.

[0079] In some embodiments of the present application, the first gear roller 313 and the load-bearing portion 315 are heated and then rolled onto the edge areas of the first diaphragm 11 and the edge areas of the second diaphragm 13, i.e., hot pressing. Alternatively, the first gear roller 313 and the load-bearing portion 315 are configured to transmit ultrasonic energy and ultrasonically roll onto the edge areas of the first diaphragm 11 and the edge areas of the second diaphragm 13, i.e., ultrasonic lamination. Alternatively, the first gear roller 313 and the load-bearing portion 315 roll onto the edge areas of the first diaphragm 11 and the edge areas of the second diaphragm 13 at room temperature, i.e., cold pressing.

[0080] In some embodiments of the present application, the first gear roller 313 and the load-bearing part 315 are replaced by circular rollers, and the edge areas of the first diaphragm 11 and the edge areas of the second diaphragm 13 that extend beyond the side of the first electrode piece 12 are continuously rolled, so that the electrolyte can pass through the micropores of the first diaphragm 11 and the second diaphragm 13, and then the electrolyte can infiltrate the first electrode piece 12, so that the electrochemical reaction can proceed normally to generate electrical energy.

[0081] As shown in FIG11 , in some embodiments of the present application, the side diaphragm composite assembly 30 further includes a gluing mechanism 32 for applying glue between the first diaphragm 11 and the second diaphragm 13 extending beyond the side of the first electrode piece 12. Furthermore, as shown in FIG3-4 and FIG11 , the first side roller 311 and / or the second side roller 312 include a first round roller 317 and a force-bearing portion 315 . The first round roller 317 and the force-bearing portion 315 are arranged relative to each other. The first round roller 317 and the force-bearing portion 315 continuously roll the edge areas of the first diaphragm 11 and the second diaphragm 13 extending beyond the side of the first electrode piece 12 , so that the edge areas of the first diaphragm 11 and the second diaphragm 13 are quickly glued together. At this time, the electrolyte can pass through the micropores of the first diaphragm 11 and the second diaphragm 13, and then the electrolyte can infiltrate the first electrode piece 12, thereby performing a normal electrochemical reaction to generate electrical energy.

[0082] When the side membrane composite assembly 30 is located downstream of the first composite roll assembly 20, as shown in FIG4 , the gluing mechanism 32 is located between the first round roller 317 and the first composite roll assembly 20. When the side membrane composite assembly 30 is located upstream of the first composite roll assembly 20, as shown in FIG3 , the gluing mechanism 32 is located on the side of the first round roller 317 away from the first composite roll assembly 20. The following description uses the example of "the side membrane composite assembly 30 being located downstream of the first composite roll assembly 20" as an example.

[0083] In some embodiments of the present application, only the first side roller 311 includes the first circular roller 317 and the load-bearing portion 315. On the side of the first electrode piece 12 where the first electrode tab 121 is not provided, the load-bearing portion 315 supports the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13 that extend beyond the side of the first electrode piece 12. Since glue has been applied between the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13, and the first circular roller 317 continuously rolls the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13, the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13 are continuously rolled together by the composite glue.

[0084] In some embodiments of the present application, only the second side roller 312 includes a first circular roller 317 and a load-bearing portion 315. On the side of the first pole piece 12 where the first pole tab 121 is provided, the load-bearing portion 315 supports the edge region of the first diaphragm 11, the edge region of the second diaphragm 13, and each first pole tab 121 that extends beyond the side of the first pole piece 12. Furthermore, the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13 that extend beyond the first pole piece 12 between two adjacent first pole tabs 121 have been coated with glue and continuously rolled by the first circular roller 317. Therefore, the edge region of the first diaphragm 11 and the edge region of the second diaphragm 13 are continuously rolled and bonded together by the composite glue.

[0085] In some embodiments of the present application, the first side roller 311 and the second side roller 312 both include a first round roller 317 and a load-bearing portion 315 , which can simplify the coordination layout of the first side roller 311 and the second side roller 312 and reduce the overall cost of the pole piece composite device.

[0086] In some embodiments of the present application, the load-bearing portion 315 can be, but is not limited to, configured as a second circular roller, a load-bearing workbench, or the like. When the load-bearing portion 315 is configured as a second circular roller, the second circular roller rotates synchronously with the first circular roller 317, with the first circular roller 317 and the second circular roller rotating in opposite directions. Furthermore, the synchronously moving first and second circular rollers 317 and 317 can also provide a driving force for the composite strip 14 to move backward, thereby improving composite efficiency.

[0087] As shown in FIG11 , in some embodiments of the present application, the side diaphragm composite assembly 30 further includes an ultraviolet lamp 33, which is located downstream of the first circular roller 317. Accordingly, ultraviolet curing UV glue (UV is the abbreviation of Ultra-Violet ray, which refers to ultraviolet rays) is applied between the edge area of ​​the first diaphragm 11 and the edge area of ​​the second diaphragm 13 that extend beyond the side of the first pole piece 12. After the glue between the edge area of ​​the first diaphragm 11 and the edge area of ​​the second diaphragm 13 that extend beyond the side of the first pole piece 12 is rolled by the first circular roller 317 and the second circular roller, the glue between the first diaphragm 11 and the second diaphragm 13 that extend beyond the side of the first pole piece 12 is irradiated by the ultraviolet lamp 33, which helps to increase the curing rate of the glue, thereby improving production efficiency.

[0088] As shown in Figures 6 to 10, in some embodiments of the present application, the electrode assembly device 100 further includes a first conveyor roller 41, which is located upstream of and spaced apart from one of the first composite roller 21 and the second composite roller 22; and / or the electrode assembly device 100 further includes a second conveyor roller 42, which is located upstream of and spaced apart from the other of the first composite roller 21 and the second composite roller 22. The following description uses the example of "the electrode assembly device 100 is provided with both the first conveyor roller 41 and the second conveyor roller 42; the first conveyor roller 41 is located upstream of and spaced apart from the first composite roller 21; and the second conveyor roller 42 is located upstream of and spaced apart from the second composite roller 22." For other embodiments, please refer to the example description. The first separator 11 is lapped around the first conveyor roller 41 and conveyed obliquely between the first composite roller 21 and the second composite roller 22. The second separator 13 is lapped around the second conveyor roller 42 and conveyed obliquely between the first composite roller 21 and the second composite roller 22. The first electrode sheet 12 is horizontally conveyed between the first diaphragm 11 and the second diaphragm 13 between the first composite roller 21 and the second composite roller 22. The first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13 are rolled and laminated together by the first composite roller 21 and the second composite roller 22. As the first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13 are conveyed between the first composite roller 21 and the second composite roller 22 for stacking and roll-combining, the conveying paths of the first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13 do not interfere with each other, allowing smooth conveyance of the first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13.

[0089] As shown in FIG12 , in some embodiments of the present application, the electrode assembly device 100 further includes a first cutting mechanism 44 , which is located upstream of the first composite roller assembly 20 . The first cutting mechanism 44 is used to cut the first electrode 12 . In each wound bare cell, the length of the first electrode 12 is a calculated first predetermined length. Therefore, the first electrode 12 is cut by the first cutting mechanism 44 after being conveyed to the first predetermined length. After the first electrode 12 is cut by the first cutting mechanism 44 , the first electrode 12 stops being conveyed for a period of time, and the first diaphragm 11 and the second diaphragm 13 continue to be conveyed, thereby obtaining a blank section where the first diaphragm 11 and the second diaphragm 13 are directly roll-combined (i.e., the blank section does not contain the first electrode 12 ), and the length of the blank section is also the calculated preset length. Then, the first electrode 12 continues to be conveyed, and the first composite roller 21 and the second composite roller 22 continue to roll-combine to obtain the composite material strip 14 .

[0090] As shown in FIG12 , in some embodiments of the present application, the electrode composite device 100 further includes a first detection mechanism 45, which is located between the first cutting mechanism 44 and the first composite roller assembly 20. The first detection mechanism 45 is used to detect the conveying length of the first electrode 12, that is, the first detection mechanism 45 detects the first electrode 12 of the first predetermined length. The first detection mechanism 45 is electrically connected to the first cutting mechanism 44. Therefore, when the first detection mechanism 45 detects the first predetermined length of the first electrode 12, the first detection mechanism 45 sends a signal, and the first cutting mechanism 44 cuts the first electrode 12 according to the signal, thereby cutting off the first electrode 12 of the first predetermined length. The first detection mechanism 45 and the first cutting mechanism 44 realize the automatic cutting function of the first electrode 12, thereby improving the degree of automation and improving production efficiency.

[0091] According to another aspect of an embodiment of the present application, a bare cell winding apparatus is provided, as shown in FIG12 . The bare cell winding apparatus includes a pole piece assembly, a second composite roller assembly 50, and a winding mechanism 61. Specifically, the pole piece assembly is the pole piece assembly 100 described above. The pole piece assembly 100 outputs a composite material strip 14. The second composite roller assembly 50 is located downstream of the pole piece assembly. The second composite roller assembly 50 includes a third composite roller 51 and a fourth composite roller 52. The third composite roller 51 and the fourth composite roller 52 are arranged opposite each other and rotate synchronously. The third composite roller 51 and the fourth composite roller 52 rotate in opposite directions. The third composite roller 51 and the fourth composite roller 52 are used to composite the second pole piece 15 onto one of the first separator 11 and the second separator 13 to output the battery cell strip 10. The winding mechanism 61 is located downstream of the second composite roller assembly 50 and winds the battery cell strip 10 into a bare cell.

[0092] The electrode composite device 100 provided in the embodiment of the present application performs a composite operation on the first diaphragm 11, the first electrode piece 12, and the second diaphragm 13. Not only are the first diaphragm 11, the first electrode piece 12, and the second diaphragm 13 composited together through the first composite roller assembly 20, but also, through the operation of the side diaphragm composite assembly 30, the edge area of ​​the first diaphragm 11 that exceeds one side of the first electrode piece 12 is composited with the edge area of ​​the second diaphragm 13, and the edge area of ​​the first diaphragm 11 that exceeds the other side of the first electrode piece 12 is composited with the edge area of ​​the second diaphragm 13, thereby obtaining a composite strip 14 in which the first diaphragm 11 and the second diaphragm 13 wrap around the first electrode piece 12. The second electrode piece 15 is then rolled and composited on the first diaphragm 11 or the second diaphragm 13 of the composite strip 14 by the second composite roller assembly 50, and then a winding operation is performed to wind up a bare cell. During the winding process, the edge areas of the first diaphragm 11 and the second diaphragm 13 that extend beyond the two side edges of the first electrode piece 12 will no longer fold over even under the action of external force, thereby eliminating the overlap of the first electrode piece 12 and the second electrode piece 15 in the wound bare battery cell, so that the first electrode piece 12 and the second electrode piece 15 are well insulated and separated by the first diaphragm 11 or the second diaphragm 13, eliminating the low voltage problem of the battery caused by the overlap of the first electrode piece 12 and the second electrode piece 15, and helping to improve the product yield of the battery.

[0093] As shown in Figure 12, in some embodiments of the present application, the bare cell winding device also includes a second detection mechanism 62 and a pressing mechanism 63. The second detection mechanism 62 is located upstream of the second composite roller assembly 50. The second detection mechanism 62 can be used to detect the preset length of the end of the first pole piece 12 passing through the pressing mechanism 63. The second detection mechanism 62 is electrically connected to the pressing mechanism 63. When the second detection mechanism 62 detects that the end of the first pole piece 12 has passed the preset length relative to the pressing mechanism 63, the second detection mechanism 62 sends a signal to the pressing mechanism 63, and the pressing mechanism 63 presses the end of the second pole piece 15 against the first diaphragm 11 or the second diaphragm 13 of the composite material strip 14 according to the signal. Through the cooperation of the second detection mechanism 62 and the pressing mechanism 63, the end of the second pole piece 15 can be pressed against the composite material strip 14 accurately and quickly, thereby accurately determining the center distance between the first pole tab 121 of the first pole piece 12 and the second pole tab of the second pole piece 15, thereby improving production efficiency.

[0094] Furthermore, after the second pole piece 15 is laminated onto the composite strip 14, the center-to-center distance between the first pole tab 121 and the second pole tab is fixed. Even during the winding process, the center-to-center distance between the first pole tab 121 and the second pole tab remains unchanged. This improves the quality of the bare cell and, in turn, the quality of the produced battery.

[0095] In some related technologies, as shown in FIG1 , a first electrode and a diaphragm are combined together by a composite roller 300 to form a first composite material strip 301, and the edge areas on both sides of the diaphragm extend beyond the side edges of the first electrode; a second electrode and another diaphragm are also combined together by another composite roller 300 to form a second composite material strip 302, and the edge areas on both sides of the diaphragm extend beyond the side edges of the second electrode. Then, the first composite material strip 301 and the second composite material strip 302 are stacked and passed through a winding mechanism 61, thereby being wound into a bare battery cell. However, during the winding process, when the running length of the first composite material strip 301 reaches a predetermined length, the first electrode of the first composite material strip 301 is cut off but the diaphragm is not cut off. The winding mechanism 61 continues to rotate, and the diaphragm continues to be transported, while the first electrode is stopped for a period of time so that the head end of the first electrode of the next section is spaced apart from the tail end of the first electrode of the previous section by one end. At this time, the blank section of the diaphragm is stretched and deformed by the pulling of the winding mechanism 61. Similarly, when the running length of the second composite material strip 302 reaches a predetermined length, the second electrode sheet is cut off, and the blank section of the diaphragm is stretched and deformed by the winding mechanism 61. If the stretching and deformation of the blank section of the diaphragm of the first composite material strip 301 is not equal to the stretching and deformation of the blank section of the diaphragm of the second composite material strip 302, the center distance between the subsequent tabs of the first electrode sheet and the second electrode sheet will shift and change, and the center distance cannot be maintained consistent.

[0096] As shown in Figure 12, in some embodiments of the present application, the bare cell winding device further includes a second cutting mechanism 64, which is located upstream of the pressing mechanism 63, and the second cutting mechanism 64 is located downstream of the second detection mechanism 62 (that is, the second cutting mechanism 64 is located between the second detection mechanism 62 and the pressing mechanism 63). In each wound bare cell, the length of the second electrode 15 is a calculated second predetermined length. Therefore, the second electrode 15 is cut off when the second detection mechanism 62 detects the predetermined conveying length of the second electrode 15 (that is, the second predetermined length) by the second cutting mechanism 64. The second cutting mechanism 64 is electrically connected to the second detection mechanism 62, that is, when the second detection mechanism 62 detects the second predetermined length of the second electrode 15, the second detection mechanism 62 sends a signal to the second cutting mechanism 64, and then the second cutting mechanism 64 cuts off the second electrode 15 according to the signal. After the second electrode 15 is cut by the second cutting mechanism 64, the second electrode 15 stops conveying for a period of time to correspond to the blank section where the first diaphragm 11 and the second diaphragm 13 are directly compounded.

[0097] Furthermore, the second detection mechanism 62 is electrically connected to the first detection mechanism 45. When the first detection mechanism 45 detects the first predetermined length of the first electrode piece 12 and sends a signal to the first cutting mechanism 44, the first detection mechanism 45 also sends a signal to the second detection mechanism 62 to instruct the first cutting mechanism 44 to perform a cutting operation. Thus, the first detection mechanism 45 interacts with the second detection mechanism 62 to confirm that the previous process is being performed normally and correctly. Then, when the second detection mechanism 62 detects the second predetermined length of the second electrode piece 15, it sends a signal to the second cutting mechanism 64. If the first detection mechanism 45 does not send a signal to the second detection mechanism 62 for a long period of time, the second detection mechanism 62 prejudges that the first detection mechanism 45 has failed and issues an alarm to prompt the staff to perform maintenance on the first detection mechanism 45. Furthermore, the second cutting mechanism 64 is electrically connected to the first detection mechanism 45, so that the first detection mechanism 45 serves as a backup for the second detection mechanism 62. When the second detection mechanism 62 fails (that is, the second detection mechanism 62 does not send a signal to the first detection mechanism 45 within the predetermined time), the first detection mechanism 45 predicts that the second detection mechanism 62 has failed. At this time, the first detection mechanism 45 issues an alarm to prompt the staff to inspect and maintain the second detection mechanism 62, and the first detection mechanism 45 sends a signal to the second cutting mechanism 64. The second cutting mechanism 64 cuts the second electrode 15 according to the signal sent by the first detection mechanism 45, thereby obtaining a second electrode 15 of a second predetermined length.

[0098] As shown in FIG12 , in some embodiments of the present application, the bare cell winding device further includes a third conveyor roller 43, which is located upstream of the second detection mechanism 62. The second electrode sheet 15 is wound around the third conveyor roller 43 so that the second electrode sheet 15 is conveyed obliquely to the pressing mechanism 63, so that the second electrode sheet 15 can always be smoothly conveyed, thereby improving production efficiency. In addition, the third conveyor roller 43 is used to reasonably arrange the incoming material position of the second electrode sheet 15 (i.e., the placement position for storing the second electrode sheet 15), thereby optimizing the utilization of the plant space.

[0099] As shown in Figure 12, in some embodiments of the present application, the bare cell winding equipment also includes a demolding guide roller 65, which is located downstream of the second composite roller assembly 50. The demolding guide roller 65 is used to peel off the release film 16 of the electrostatic protective film compounded on the second pole piece 15. In the process of compounding the second pole piece 15 on the first diaphragm 11 or the second diaphragm 13 of the composite material strip 14, the electrostatic protective film is also compounded on the second pole piece 15. Among them, the electrostatic protective film is attached to the release film 16. The side of the electrostatic protective film facing away from the release film 16 is fixed on the second pole piece 15, and then fixed on the pressing mechanism 63. At this time, the release film 16, the electrostatic protective film and the second pole piece 15 are stacked on the pressing mechanism 63 in sequence. After the release film 16 passes through the third composite roller 51 and the fourth composite roller 52, the release film 16 is wrapped around the film stripping guide roller 65, so that the release film 16 is separated from the electrostatic protective film upward, achieving a rapid peeling operation of the release film 16 and improving production efficiency.

[0100] According to another aspect of the embodiments of the present application, a bare cell winding method is provided, as shown in FIG13 . The bare cell winding method includes the following core steps:

[0101] Step S10: laminating the first diaphragm 11, the first pole piece 12 and the second diaphragm 13 in sequence to obtain a composite material strip 14;

[0102] Step S20: Composite the second electrode sheet 15 onto one of the first diaphragm 11 and the second diaphragm 13 of the composite material strip 14 to form the battery core material strip 10. At this time, the center distance between the first electrode tab 121 of the first electrode sheet 12 and the second electrode tab of the second electrode sheet 15 on the battery core material strip 10 is fixed;

[0103] Step S40: The battery cell strip 10 is wound to form a bare battery cell. Since the center distance between the first pole ear 121 of the first pole piece 12 and the second pole ear of the second pole piece 15 on the battery cell strip 10 is fixed, the center distance between the first pole ear 121 and the second pole ear of the battery cell strip 10 will no longer be offset and expanded during the winding process, thereby effectively improving the product quality of the bare battery cell.

[0104] In the related art, the compounding process and the winding process are combined and operated together. As shown in Figure 1, the first electrode and a diaphragm are compounded together by a compounding roller to form a first composite material strip, and the edge areas on both sides of the diaphragm exceed the side edges of the first electrode; the second electrode and another diaphragm are also compounded together by a compounding roller to form a second composite material strip. After the first composite material strip is wound on the winding mechanism, the starting end of the second composite material strip is then conveyed to the winding mechanism. Since the starting end of the second composite material strip is in a free state for a period of time before being conveyed to the winding mechanism (at this time, the starting end of the second composite material strip becomes the free end A, as shown in Figure 2). Therefore, during this period of time, the free end A of the second composite material strip is subjected to external force and will swing (such as the swing of the free end A caused by the external force of the winding correction effect), resulting in the free end A not being able to be quickly conveyed to the winding mechanism, thereby affecting the winding work efficiency. In serious cases, the free end A may even be unable to be accurately conveyed to the winding mechanism, resulting in the scrapping of the wound bare cell, affecting the product quality and production yield of the bare cell. The bare cell winding method provided in the embodiment of the present application is used to wind and form a bare cell. Since the first diaphragm 11, the first electrode 12, the second diaphragm 13 and the second electrode 15 are compounded to form a cell strip 10 through steps S10 and S20, and then the winding operation is performed, that is, the end of the cell strip 10 formed by the first diaphragm 11, the first electrode 12, the second diaphragm 13 and the second electrode 15 is fixed on the winding mechanism 61 at one time. Compared with the winding operation of the related art, the problem that the free end A of the second composite material strip is swung under the action of external force, resulting in the free end A cannot be accurately transported to the winding mechanism and accurately aligned with the first composite material strip for winding is eliminated. Not only the winding work efficiency is greatly improved, but also the winding quality of the bare cell is improved, and the product yield of the bare cell is significantly improved.

[0105] As shown in Figure 14, in some embodiments of the present application, before executing step S40, that is, before executing "winding the battery cell strip 10 into a bare battery cell", the bare battery cell winding method also includes step S30: compounding the first diaphragm 11 and the second diaphragm 13 that extend beyond one side of the first pole piece 12; compounding the first diaphragm 11 and the second diaphragm 13 that extend beyond the other side of the first pole piece 12. By compounding the edge area of ​​the first diaphragm 11 that exceeds one side of the first electrode sheet 12 with the edge area of ​​the second diaphragm 13, and compounding the edge area of ​​the first diaphragm 11 that exceeds the other side of the first electrode sheet 12 with the edge area of ​​the second diaphragm 13, the first diaphragm 11 and the second diaphragm 13 wrap the first electrode sheet 12. In this way, when the battery core strip 10 is wound, the edge area of ​​the first diaphragm 11 and the edge area of ​​the second diaphragm 13 that exceed the two side edges of the first electrode sheet 12 are not easy to fold even under the action of external force, or even if they are folded, the first and second electrode sheets will not be exposed, and the first and second electrode sheets will not be overlapped, thereby eliminating the overlap of the first and second electrode sheets 12 and 15 in the wound bare battery cell, so that the first and second electrode sheets 12 and 15 are well insulated and separated by the first diaphragm 11 or the second diaphragm 13, eliminating the low voltage problem of the battery caused by the overlap of the first and second electrode sheets 12 and 15, and helping to improve the product yield of the battery.

[0106] Among them: step S30 can be executed after step S20 is completed; or, step S30 can be executed after step S10 is completed and before step S20 is executed, which is a better solution, as shown in Figure 14; or, step S30 can be executed before step S10 is executed.

[0107] In fact, the bare cell winding method provided by the embodiment design of the present application can be but is not limited to being performed by the above-mentioned bare cell winding equipment provided by the embodiment design of the present application, thereby manufacturing formed bare cells, which not only improves the production efficiency of the bare cells, but also improves the product quality and product yield of the bare cells.

[0108] As shown in Figures 12 and 14, in some embodiments of the present application, when executing step S10, that is, when "the first diaphragm 11, the first electrode sheet 12, and the second diaphragm 13 are laminated together in sequence", the bare cell winding method further includes step S11: detecting a first predetermined length of the first electrode sheet 12, and cutting the first electrode sheet 12 according to the first predetermined length. Furthermore, when executing step S20, that is, when "the second electrode sheet 15 is laminated on one of the first diaphragm 11 and the second diaphragm 13 to form the battery strip 10", the bare cell winding method further includes step S21: detecting a second predetermined length of the second electrode sheet 15, and cutting the second electrode sheet 15 according to the second predetermined length. The first predetermined length is greater than the second predetermined length, and both ends of the first electrode sheet 12 obtained by cutting extend beyond both ends of the second electrode sheet 15, thus meeting the standard requirement that the first electrode sheet be longer than the second electrode sheet in the production of bare cells. The first detection mechanism 45 of the bare cell winding device detects the first predetermined length of the first electrode sheet 12, and then the first cutting mechanism 44 cuts the first electrode sheet 12 to obtain the first predetermined length of the first electrode sheet 12. Furthermore, the second detection mechanism 62 of the bare cell winding device detects the second predetermined length of the second electrode sheet 15, and then the second cutting mechanism 64 cuts the second electrode sheet 15 to obtain the second predetermined length of the second electrode sheet 15. In this way, the automation process of winding bare cells is greatly improved, which can greatly improve the production efficiency of bare cells.

[0109] As shown in Figures 9-10 and 14, in some embodiments of the present application, before executing step S10, that is, before executing "stacking the first diaphragm 11, the first electrode piece 12 and the second diaphragm 13 together in sequence", the bare cell winding method also includes step 01: fixing the end of the first electrode piece 12 on one of the first diaphragm 11 and the second diaphragm 13.

[0110] The end of the first electrode piece 12 can be positioned on one of the first diaphragm 11 and the second diaphragm 13 using a positioning tape 66. As shown in FIG9 , one end of the positioning tape 66 is attached to the end of the first electrode piece 12, and then the other end of the positioning tape 66 is attached to one of the first diaphragm 11 and the second diaphragm 13 to position the end of the first electrode piece 12. The first diaphragm 11, the first electrode piece 12, and the second diaphragm 13 are then stacked in sequence and passed through the first and second laminating rollers 21 and 22 to obtain a composite material strip 14.

[0111] Alternatively, the end of the first electrode piece 12 can also be positioned on one of the first diaphragm 11 and the second diaphragm 13 by means of a positioning adhesive 67. As shown in FIG10 , a positioning adhesive 67 (i.e., glue) is applied to one of the first diaphragm 11 and the second diaphragm 13, and then the end of the first electrode piece 12 is adhered and fixed to one of the first diaphragm 11 and the second diaphragm 13 by means of the positioning adhesive 67. This can position the end of the first electrode piece 12. Then, the first diaphragm 11, the first electrode piece 12, and the second diaphragm 13 are sequentially stacked and passed through the first composite roller 21 and the second composite roller 22, thereby obtaining the composite material strip 14 after composite.

[0112] By positioning the end of the first pole piece 12, the frequency of the first pole piece 12 offsetting relative to the first diaphragm 11 and the second diaphragm 13 is reduced or even eliminated during the composite molding process of the composite material strip 14, thereby improving the composite work efficiency and the composite quality.

[0113] The bare cell prepared by the electrode composite device, bare cell winding equipment and bare cell winding method provided by the embodiment of the present application is applied to battery manufacturing. The lithium battery produced can be used for, but not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery cars, electric cars, ships, spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles and spacecraft, etc.

[0114] The above are merely optional embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included within the scope of the claims of the present application.

Claims

1. A pole piece composite device, wherein: include: A first composite roller assembly, comprising a first composite roller and a second composite roller, wherein the first composite roller and the second composite roller are arranged opposite to each other, and the first composite roller and the second composite roller are used to laminate and composite the first diaphragm, the first pole piece and the second diaphragm in sequence; The side diaphragm composite component is used to composite the portion of the first diaphragm extending beyond the side of the first pole piece with the portion of the second diaphragm extending beyond the side of the first pole piece.

2. The pole piece composite device according to claim 1, wherein: The side diaphragm composite assembly includes a first side roller and a second side roller, the first side roller corresponds to the first side of the first pole piece where no pole ear is provided, and the second side roller corresponds to the second side of the first pole piece where the pole ear is provided, the first side roller is used to roll and composite the first diaphragm and the second diaphragm together with their portions exceeding the first side, and the second side roller is used to roll and composite the first diaphragm and the second diaphragm together with their portions exceeding the second side.

3. The pole piece composite device according to claim 2, wherein: The first side roller and / or the second side roller comprises a first gear roller and a load-bearing portion, and the first gear roller and the load-bearing portion are arranged opposite to each other.

4. The pole piece composite device according to claim 3, wherein: The load-bearing portion is configured as a second gear roller, and the first gear roller and the second gear roller are configured such that during rotation, the convex teeth of the first gear roller and the convex teeth of the second gear roller press the first diaphragm and the second diaphragm in a one-to-one correspondence.

5. The pole piece composite device according to claim 3 or 4, wherein: The second side roller comprises a first gear roller, the pitch between two adjacent protruding teeth of the first gear roller is greater than or equal to the width of the pole lug, and the protruding teeth of the first gear roller are used to roll and laminate the first diaphragm and the second diaphragm parts located between two adjacent pole lugs.

6. The pole piece composite device according to claim 2, wherein: The side diaphragm composite assembly may be additionally provided with a glue coating mechanism, the first side roller and / or the second side roller comprises a first round roller and a load-bearing part, the first round roller and the load-bearing part are arranged opposite to each other, the glue coating mechanism is located upstream of the first round roller, and the glue coating mechanism is used to apply glue between the parts of the first diaphragm and the second diaphragm that extend beyond the side of the first pole piece.

7. The pole piece composite device according to claim 6, wherein: The load-bearing part is configured as a second circular roller, and the second circular roller rotates synchronously with the first circular roller.

8. The pole piece composite device according to claim 6 or 7, wherein: The side diaphragm composite assembly may be additionally provided with an ultraviolet lamp, which is located downstream of the first round roller and is used to irradiate the glue-coated parts of the first diaphragm and the second diaphragm.

9. The pole piece composite device according to any one of claims 1 to 8, wherein: The electrode composite device further includes a first conveying roller, the first conveying roller is located upstream of one of the first composite roller and the second composite roller and is spaced therefrom, and one of the first diaphragm and the second diaphragm is wrapped around the first conveying roller to be obliquely conveyed between the first composite roller and the second composite roller; And / or, the electrode composite device also includes a second conveying roller, which is located upstream of the other of the first composite roller and the second composite roller and is spaced apart from it, and the other of the first diaphragm and the second diaphragm is wrapped around the second conveying roller to be conveyed obliquely between the first composite roller and the second composite roller.

10. The pole piece composite device according to any one of claims 1 to 9, wherein: The pole piece composite device further includes a first cutting mechanism, which is located upstream of the first composite roller assembly and is used to cut off the first pole piece.

11. The pole piece composite device according to claim 10, wherein: The electrode sheet composite device further includes a first detection mechanism, which is located between the first cutting mechanism and the first composite roller assembly, and is electrically connected to the first cutting mechanism, and is used to detect the conveying length of the first electrode sheet.

12. A bare cell winding device, wherein: include: The pole piece composite device according to any one of claims 1 to 11, wherein the pole piece composite device outputs a composite material strip formed by sequentially stacking and composited the first diaphragm, the first pole piece, and the second diaphragm; A second composite roller assembly, located downstream of the electrode sheet composite device, is used to composite the second electrode sheet onto one of the first diaphragm and the second diaphragm to output the battery core strip; The winding mechanism is located downstream of the second composite roller assembly and is used for winding the battery core material strip to form a bare battery core.

13. The bare cell winding device according to claim 12, wherein: The second composite roller assembly includes a third composite roller and a fourth composite roller, the third composite roller and the fourth composite roller are arranged opposite to each other, and the third composite roller and the fourth composite roller are used to composite the second pole piece on one of the first diaphragm and the second diaphragm.

14. The bare cell winding device according to claim 12 or 13, wherein: The bare cell winding device also includes a second detection mechanism and a pressing mechanism. The second detection mechanism is located upstream of the second composite roller assembly. The second detection mechanism is electrically connected to the pressing mechanism. The pressing mechanism is used to press the end of the second pole piece against one of the first diaphragm and the second diaphragm.

15. The bare cell winding device according to claim 14, wherein: The bare cell winding device also includes a second cutting mechanism, which is located upstream of the pressing mechanism. The second cutting mechanism is electrically connected to the second detection mechanism, and the second cutting mechanism is used to cut off the second pole piece when the second detection mechanism detects a predetermined conveying length of the second pole piece.

16. The bare cell winding device according to claim 15, wherein: The bare cell winding device also includes a third conveying roller, which is located upstream of the second cutting mechanism. The second pole piece is wrapped around the third conveying roller so that the second pole piece is conveyed to the pressing mechanism at an angle.

17. The bare cell winding device according to any one of claims 13 to 16, wherein: The bare cell winding device may be additionally provided with a film stripping guide roller, wherein the film stripping guide roller is located downstream of the second composite roller assembly, and the film stripping guide roller is used to peel off the release film composited to the second pole piece.

18. A bare cell winding method, wherein: The following steps are involved: The first diaphragm, the first pole piece and the second diaphragm are laminated together in sequence; Compounding a second pole piece on one of the first diaphragm and the second diaphragm to form a battery core strip; The battery core material strip is wound to form a bare battery core.

19. The bare cell winding method according to claim 18, wherein: Before "winding the battery core material strip into a bare battery core", the bare battery core winding method further comprises: The first diaphragm is combined with a portion of the second diaphragm that exceeds a side edge of the first pole piece.

20. The bare cell winding method according to claim 18 or 19, wherein: In the step of “combining the first diaphragm, the first pole piece and the second diaphragm in a stacked manner”, the running length of the first pole piece is detected, and the first pole piece is cut off when the running length reaches a first predetermined length; Furthermore, in the step of "combining the second pole piece on one of the first diaphragm and the second diaphragm to form a battery core strip", the running length of the second pole piece is detected, and the second pole piece is cut off when the running length is a second predetermined length.

21. The bare cell winding method according to claim 20, wherein: The first predetermined length is greater than the second predetermined length, and both ends of the first pole piece obtained by cutting are beyond both ends of the second pole piece.

22. The bare cell winding method according to any one of claims 18 to 21, wherein: Before the step of "combining the first diaphragm, the first pole piece and the second diaphragm in sequence by stacking them together", the bare cell winding method further includes the step of: fixing the end of the first pole piece on one of the first diaphragm and the second diaphragm.

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