Electrode sheet preparation method, electrode sheet preparation apparatus, electrode sheet and battery cell

Abstract

An electrode sheet preparation method, an electrode sheet preparation apparatus, an electrode sheet and a battery cell. The electrode sheet preparation method comprises: cutting a dry electrode film material to form dry electrode films; cutting a current collector material to form current collectors, wherein the size of the current collectors is less than or equal to the size of the dry electrode films; and stacking multiple dry electrode films, a current collector and multiple dry electrode films in sequence, and performing pressing to form an electrode sheet, wherein the multiple dry electrode films on a same side of the current collector are arranged alternately face up and face down relative to the current collector.

Description

Electrode sheet preparation method, electrode sheet preparation device, electrode sheet and battery cell

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202410375915.4 and application date of March 29, 2024, and claims the priority of the above-mentioned Chinese patent application. The entire content of the above-mentioned Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to an electrode sheet preparation method, an electrode sheet preparation device, an electrode sheet, a battery cell and a battery device. Background Art

[0004] In recent years, a new dry electrode manufacturing technology has emerged. The electrode film is prepared by a solvent-free method and then bonded to the current collector to form an electrode. This method is environmentally friendly and does not require solvent evaporation, which greatly reduces costs. In addition, the dry electrode does not use solvents in the production process, and the binder exists in fiber or sheet form, which does not affect the internal contact between the active material particles. The electrode has good conductivity, high capacity, and good rate performance.

[0005] However, at present, dry electrode membranes are basically directly rolled together with current collectors to obtain electrode rolls. Due to the uneven thickness of dry electrode membranes, as can be seen from Figure 1, the thickness of the electrode rolls will be uneven. During the pressing process, uneven extension will occur, and obvious depressions, bulges and other deformations will appear. In addition, in the general laminated battery production process, the electrode rolls need to be cut and laminated. During cutting, burrs are prone to appear on the aluminum foil or copper foil, which affects the safety performance of the lithium-ion battery.

[0006] Summary of the Invention

[0007] The present application aims to solve one of the technical problems in the related art at least to a certain extent.

[0008] To this end, one purpose of the present application is to propose a method for preparing an electrode sheet to improve the flatness of the electrode sheet after lamination, reduce the risk of defects such as burrs on the electrode sheet, and improve the safety performance of the battery cell.

[0009] The present application further proposes an electrode sheet preparation device.

[0010] The present application further proposes an electrode sheet.

[0011] The present application further proposes a battery cell.

[0012] The present application further proposes a battery device.

[0013] According to the electrode sheet preparation method of the embodiment of the present application, the method includes: cutting the dry electrode film material to form a dry electrode film; cutting the current collector material to form a current collector, the size of the current collector is less than or equal to the size of the dry electrode film; stacking multiple layers of dry electrode film, current collector and multiple layers of dry electrode film in this order and then pressing them to form an electrode sheet, and the multiple layers of dry electrode film located on the same side of the current collector are placed alternately in front and back relative to the current collector.

[0014] According to the electrode sheet preparation method of the embodiment of the present application, by placing the multi-layer dry electrode membrane in an alternating manner relative to the current collector in a positive and negative direction, the risk of uneven thickness of the electrode sheet can be reduced, thereby improving the flatness of the electrode sheet after lamination, and reducing the risk of defects such as burrs on the electrode sheet, thereby improving the safety performance of the battery cell.

[0015] According to the embodiment of the present application, the electrode sheet preparation device includes: a fixed frame, the top wall of the fixed frame is provided with a linear module, the linear module has a movable block that can move along a first direction; a laminator, the laminator is arranged in the fixed frame, the laminator includes a laminating machine body and a pressure head, the laminating machine body is movably provided on the bottom wall of the fixed frame, the pressure head is provided on the top wall of the fixed frame, along the second direction the pressure head is located on one side of the linear module, the laminating machine body selectively moves to below the pressure head, the first direction, the second direction and the height direction of the electrode sheet preparation device are perpendicular to each other; two placing tables, along the first direction, the two placing tables are arranged in the fixed frame and on the bottom wall of the fixed frame, and the two placing tables are respectively arranged on both sides of the laminating machine body; a suction component, the suction component is connected to the movable block, and drives the suction component to move when the movable block moves, the suction component includes two adsorption structures, the two adsorption structures can be raised and lowered along the height direction of the electrode sheet preparation device, the two adsorption structures are arranged along the first direction, and the adsorption structure is used to selectively absorb the dry electrode film of the electrode sheet.

[0016] According to the electrode sheet preparation device of the embodiment of the present application, by arranging two placement tables on both sides of the laminating body, the placement directions of the dry electrode membranes on the two placement tables are opposite, so that the two adsorption structures can absorb the dry electrode membranes on the corresponding placement tables in turn, and the dry electrode membranes on the corresponding placement tables can be stacked on the current collector in turn, so that the multi-layer dry electrode membranes can be placed alternately in front and back relative to the current collector, reducing the risk of uneven thickness of the electrode sheet, thereby improving the flatness of the electrode sheet after lamination, and can also reduce the risk of defects such as burrs on the electrode sheet, thereby improving the safety performance of the battery cell.

[0017] According to the electrode sheet of the embodiment of the present application, it is prepared according to the electrode sheet preparation method of the above embodiment, and the electrode sheet includes: a current collector and a multilayer dry electrode film, the current collector and the multilayer dry electrode film are stacked, the current collector has a first side and a second side relative to each other, the first side and the second side are both provided with a multilayer dry electrode film, and the multilayer dry electrode film located on the same side of the current collector is placed alternately in front and back relative to the current collector.

[0018] According to the electrode sheet of the embodiment of the present application, the current collector and the multi-layer dry electrode film are stacked. Along the thickness direction of the current collector, the current collector has a first side and a second side relative to each other. The first side and the second side are both provided with a multi-layer dry electrode film, and the multi-layer dry electrode film located on the same side of the current collector is placed alternately in front and back relative to the current collector, thereby reducing the risk of uneven thickness of the electrode sheet, thereby improving the flatness of the electrode sheet after lamination, and can also reduce the risk of defects such as burrs on the electrode sheet.

[0019] A battery cell according to an embodiment of the present application includes the electrode sheet according to the above embodiment.

[0020] According to the battery cell of the embodiment of the present application, by arranging two placement tables on both sides of the laminating body respectively, the placement directions of the dry electrode membranes on the two placement tables are opposite, so that the two adsorption structures can absorb the dry electrode membranes on the corresponding placement tables in turn, and the dry electrode membranes on the corresponding placement tables can be stacked on the current collector in turn, so that the multi-layer dry electrode membranes can be placed alternately in front and back relative to the current collector, reducing the risk of uneven thickness of the electrode sheet, thereby improving the flatness of the electrode sheet after lamination, and can also reduce the risk of defects such as burrs on the electrode sheet, thereby improving the safety performance of the battery cell.

[0021] The battery device according to an embodiment of the present application includes the battery cell of the above embodiment.

[0022] According to the battery device of the embodiment of the present application, by arranging two placement tables on both sides of the lamination body respectively, the placement directions of the dry electrode membranes on the two placement tables are opposite, so that the two adsorption structures can absorb the dry electrode membranes on the corresponding placement tables in turn, and the dry electrode membranes on the corresponding placement tables are stacked on the current collector in turn, so that the multi-layer dry electrode membranes can be placed alternately in front and back relative to the current collector, reducing the risk of uneven thickness of the electrode sheet, thereby improving the flatness of the electrode sheet after lamination, and can also reduce the risk of defects such as burrs on the electrode sheet, thereby improving the safety performance of the battery cell, and thus improving the safety performance of the battery device.

[0023] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a schematic diagram of a dry electrode membrane stacking structure in the prior art;

[0025] FIG2 is a flow chart of an electrode sheet preparation method according to an embodiment of the present application;

[0026] FIG3 is a schematic structural diagram of an electrode sheet preparation device according to an embodiment of the present application;

[0027] FIG4 is a bottom view of a fixing bracket according to an embodiment of the present application;

[0028] FIG5 is a schematic structural diagram of a material suction assembly according to an embodiment of the present application;

[0029] FIG6 is a partially enlarged view of a suction assembly according to an embodiment of the present application;

[0030] FIG7 is a schematic structural diagram of a laminator according to an embodiment of the present application;

[0031] FIG8 is a top view of a laminating body according to an embodiment of the present application;

[0032] FIG9 is a schematic diagram of the stacking order of the current collector and the dry electrode membranes on both sides thereof according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0034] The electrode sheet preparation device according to an embodiment of the present application is described below with reference to Figures 2 to 9.

[0035] As shown in FIG2 , the electrode sheet preparation method according to an embodiment of the present application includes:

[0036] S1. Cutting the dry electrode membrane material to form a dry electrode membrane.

[0037] The dry electrode membrane material is cut so that the shape and size of the dry electrode membrane match the shape and size of the electrode sheet. It should be noted that the dry electrode membrane includes a positive electrode dry electrode membrane and a negative electrode dry electrode membrane.

[0038] S2. Cut the current collector material to form a current collector, the size of which is smaller than or equal to the size of the dry electrode film.

[0039] Wherein, as some embodiments of the present application, the current collector material can be constructed as aluminum foil. As some embodiments of the present application, the current collector material can be constructed as copper foil. The current collector material is cut so that the shape and size of the current collector are adapted to the shape of the electrode sheet. It should be noted that the size of the current collector is adapted to the size of the dry electrode film. As some embodiments of the present application, the size of the current collector is smaller than the size of the dry electrode film. As some embodiments of the present application, the size of the current collector is equal to the size of the dry electrode film, so that the dry electrode film and the current collector can be smoothly pressed to form an electrode sheet and the dry electrode film can cover the current collector.

[0040] S3. Stacking the multi-layer dry electrode film, the current collector and the multi-layer dry electrode film in this order and pressing them to form an electrode sheet, and the multi-layer dry electrode film on the same side of the current collector is placed alternately in front and back relative to the current collector.

[0041] In some embodiments of the present invention, the stacked multi-layer dry electrode film, the current collector, and the multi-layer dry electrode film are stacked in this order, and along the thickness direction of the current collector, the multi-layer dry electrode film on one side of the current collector is placed alternately in front and back relative to the current collector, and the multi-layer dry electrode film on the other side of the current collector is also placed alternately in front and back relative to the current collector. In some embodiments of the present application, the stacked multi-layer dry electrode film, the current collector, and the multi-layer dry electrode film can be pressed by a laminator to form an electrode sheet.

[0042] It should be noted that the positive electrode sheet is formed by pressing the positive electrode dry-process electrode film, and the negative electrode sheet is formed by pressing the negative electrode dry-process electrode film. Along the thickness direction of the current collector, the multi-layer dry-process electrode film on both sides of the current collector can cover the edges of the current collector, reducing the risk of burrs on the electrode sheet.

[0043] Specifically, the dry electrode film material is cut so that the shape and size of the dry electrode film are adapted to the shape and size of the electrode sheet. It should be noted that the dry electrode film includes a positive electrode dry electrode film and a negative electrode dry electrode film. The current collector material is cut so that the shape and size of the current collector are adapted to the shape of the electrode sheet. It should be noted that the size of the current collector is adapted to the size of the dry electrode film. As some embodiments of the present application, the size of the current collector is smaller than the size of the dry electrode film. As some embodiments of the present application, the size of the current collector is equal to the size of the dry electrode film, so that the dry electrode film and the current collector can be smoothly pressed to form an electrode sheet.

[0044] As some embodiments of the present application, the current collector may include a positive electrode current collector and a negative electrode current collector. The positive electrode sheet is prepared by placing multiple layers of positive electrode dry-process electrode membranes alternately in front and back, and the positive electrode current collector and multiple layers of positive electrode dry-process electrode membranes alternately in front and back, and then pressing the stacked positive electrode dry-process electrode membranes and the positive electrode current collector.

[0045] The negative electrode sheet is prepared by placing multiple layers of negative dry electrode membranes alternately in front and back, placing the negative electrode current collector and multiple layers of negative dry electrode membranes alternately in front and back, and then pressing the stacked negative dry electrode membranes and negative electrode current collectors.

[0046] The multilayer dry electrode film, the current collector, and the multilayer dry electrode film are stacked in this order, and along the thickness direction of the current collector, the multilayer dry electrode film on one side of the current collector is placed alternately in front and back relative to the current collector, and the multilayer dry electrode film on the other side of the current collector is also placed alternately in front and back relative to the current collector. In some embodiments of the present application, the stacked multilayer dry electrode film, the current collector, and the multilayer dry electrode film can be pressed by a laminator to form an electrode sheet.

[0047] By placing the dry-process electrode films on the same side of the current collector in sequence, the uneven thickness of the electrode film that occurs during the pressing process can be eliminated, and the safety performance of the electrode sheet can be improved. The size of the multilayer electrode film is greater than or equal to the size of the current collector. During the lamination process, the first electrode film layer or the second electrode film layer can be uniformly deformed and extended toward the edge, covering the cut edge of the current collector, which can eliminate the influence of burrs. At the same time, alternating the front and back of the electrode film can effectively reduce the risk of local excessive thickness or thinness due to stacking the electrode film only on the front or back, thereby improving the flatness of the electrode sheet.

[0048] Therefore, through the electrode sheet preparation method of the present application, the multi-layer dry electrode membrane is placed alternately in the positive and negative directions relative to the current collector, which can reduce the risk of uneven thickness of the electrode sheet, thereby improving the flatness of the electrode sheet after lamination, and can also reduce the risk of defects such as burrs on the electrode sheet, thereby improving the safety performance of the battery cell.

[0049] In some embodiments of the present application, as shown in FIG9 , the current collector is provided with a tab.

[0050] Among them, the tab is an important interface connecting the current collector inside the battery cell and the external circuit. By providing a tab on the current collector, the current generated by the battery cell can be conducted to the external circuit through the tab.

[0051] As shown in Figures 3 to 6, according to the electrode sheet preparation device of the embodiment of the present application, the electrode sheet is manufactured using the electrode sheet preparation device according to the electrode sheet preparation method in the above embodiment. The electrode sheet preparation device includes: a fixed frame 10, the top wall of the fixed frame 10 is provided with a linear module 11, the linear module 11 has a movable block that can move along a first direction; a laminator, the laminator is arranged in the fixed frame 10, the laminator includes a laminating machine body 40 and a pressing head 41, the laminating machine body 40 is movably arranged on the bottom wall of the fixed frame 10, the pressing head 41 is arranged on the top wall of the fixed frame 10, along the second direction, the pressing head 41 is located on one side of the linear module 11, and the laminating machine body 40 is provided with a pressing head 41. 0 selectively moves to the bottom of the pressure head 41, and the first direction, the second direction and the height direction of the electrode sheet preparation device are perpendicular to each other; two placement tables 30, along the first direction, the two placement tables 30 are arranged in the fixed frame 10 and on the bottom wall of the fixed frame 10, and the two placement tables 30 are respectively arranged on both sides of the laminating machine body 40; the suction component, the suction component is connected to the moving block, and drives the suction component to move when the moving block moves. The suction component includes two adsorption structures, and the two adsorption structures can be raised and lowered along the height direction of the electrode sheet preparation device. The two adsorption structures are arranged along the first direction, and the adsorption structure is used to selectively absorb the dry electrode film of the electrode sheet.

[0052] Among them, along the height direction of the electrode sheet preparation device, the top wall of the fixed frame 10 is provided with a linear module 11, and the linear module 11 has a movable block, and the movable block can move back and forth along the first direction, the first direction is the X direction in Figure 1, and the first direction is perpendicular to the height direction of the electrode sheet preparation device. The laminator includes a laminating body 40 and a pressure head 41. The laminating body 40 is used to place the stacked dry electrode film and current collector, and the pressure head 41 is used to press the stacked dry electrode film and current collector on the laminating body 40 to form an electrode sheet. The laminating body 40 and the pressure head 41 are both arranged in the fixed frame 10. The laminating body 40 is movably arranged on the bottom wall of the fixed frame 10. As some embodiments of the present application, the laminating body 40 can be, but is not limited to, movably arranged on the bottom wall of the fixed frame 10 by means of a slide, a conveyor belt, etc., so that the laminating body 40 can be freely moved to a suitable position on the bottom wall of the fixed frame 10.

[0053] The pressing head 41 can be, but is not limited to, mounted on the top wall of the fixing frame 10 by means of bolts, welding, or the like. The second direction is perpendicular to the first direction and the height direction of the electrode sheet preparation apparatus. Along the second direction, i.e., the Y direction in FIG2 , the pressing head 41 is located on one side of the linear module 11, thereby reducing the risk of interference between the linear module 11 and the pressing head 41 during operation. Along the height direction of the electrode sheet preparation apparatus, the laminating body 40 is selectively moved below the pressing head 41 so that the pressing head 41 can smoothly press the dry-process electrode membrane and current collector stacked on the laminating body 40 to form an electrode sheet.

[0054] The placement table 30 is used to place the dry electrode film. The two placement tables 30 are both arranged in the fixed frame 10 and can be connected to the bottom wall of the fixed frame 10 by, but not limited to, bolts, welding, etc. Along the first direction, the two placement tables 30 are respectively arranged on both sides of the laminating machine body 40. The suction component is connected to the moving block so that when the moving block moves, it can drive the suction component to move. The suction component includes two adsorption structures. Along the height direction of the electrode sheet preparation device, the two adsorption structures can be raised and lowered so that the adsorption structure can smoothly absorb the dry electrode film of the electrode sheet. The two adsorption structures are arranged along the first direction. The two adsorption structures correspond one-to-one to the two placement tables 30. The two adsorption structures can be moved with the moving block to the top of the corresponding placement table 30. The adsorption structure can be raised and lowered to smoothly absorb the dry electrode film.

[0055] Specifically, along the thickness direction of the dry electrode film, the cut dry electrode film has two sides, front and back. The multi-layer dry electrode film is placed with the front side facing up on one placement platform 30, and the multi-layer electrode film is placed with the front side facing down on another placement platform 30. The adsorption structure is moved to the top of the corresponding placement platform 30 by the moving block, and the adsorption structure is lowered along the height direction of the electrode sheet preparation device to smoothly adsorb the dry electrode film with the front side facing up.

[0056] After the adsorption structure adsorbs the dry electrode film, it rises along the height direction of the electrode sheet preparation device and is moved to the laminating machine body 40 via a moving block. It then descends along the height direction of the electrode sheet preparation device to place the adsorbed dry electrode film facing up on the laminating machine body 40. The other adsorption structure operates in the same manner, placing the adsorbed dry electrode film facing down on the laminating machine body 40, thereby enabling the dry electrode films on the two sets of placement tables 30 to be alternately stacked on the laminating machine body 40 in opposite directions.

[0057] A current collector is placed on a certain number of stacked dry electrode films. The same number of dry electrode films are then stacked on the current collector in the same manner, but in opposite directions, to complete the stacking of multiple layers of dry electrode films, current collectors, and dry electrode films. The laminating machine 40 moves the stacked layers of dry electrode films, current collectors, and dry electrode films to the bottom of a pressing head 41, which presses the stacked layers of dry electrode films, current collectors, and dry electrode films to form an electrode sheet.

[0058] Therefore, by arranging two placement platforms 30 on both sides of the laminating body 40 respectively, the placement directions of the dry electrode membranes on the two placement platforms 30 are opposite, so that the two adsorption structures can absorb the dry electrode membranes on the corresponding placement platforms 30 in turn, and stack the dry electrode membranes on the corresponding placement platforms 30 on the current collector in turn, so that the multi-layer dry electrode membranes can be placed alternately in front and back relative to the current collector, reducing the risk of uneven thickness of the electrode sheet, thereby improving the flatness of the electrode sheet after lamination, and can also reduce the risk of burrs and other defects on the electrode sheet, thereby improving the safety performance of the battery cell.

[0059] In some embodiments of the present application, as shown in FIG. 3 , along the first direction, the intervals between the laminating body 40 and the two placement platforms 30 are the same.

[0060] In the first direction, the laminating body 40 and the two placement platforms 30 are spaced the same distance apart. That is, the distance between the laminating body 40 and the placement platform 30 on one side is L1, and the distance between the laminating body 40 and the placement platform 30 on the other side is L2, where L1 = L2. This arrangement allows for the proper positioning of the two placement platforms 30. It should be noted that the distance between the center of the laminating body 40 and the centers of the two placement platforms 30 is equal to the distance between the centers of the two adsorption structures. This facilitates the simultaneous lowering of the two adsorption structures, allowing one adsorption structure to adsorb the dry electrode film on one placement platform 30 while the other adsorption structure simultaneously deposits the dry electrode film onto the laminating body 40, thereby improving the operating efficiency of the electrode sheet preparation apparatus.

[0061] In some embodiments of the present application, as shown in FIG3 , the laminating body 40 is movably disposed on the fixing frame 10 along the second direction.

[0062] Among them, as some embodiments of the present application, the laminating body 40 can be arranged on the fixed frame 10 through a slide rail. As some embodiments of the present application, the laminating body 40 can be arranged on the fixed frame 10 through a conveyor belt, so that the laminating body 40 can be moved along the second direction, and the second direction is the Y direction of Figure 2, so that the laminating body 40 can be moved along the second direction to below the pressure head 41 or below the linear module 11, so that the laminating body 40 can have both the functions of a stacking device and a pressing device, reducing the risk of increased production costs of the electrode sheet preparation device due to separate designs of the stacking device and the pressing device, thereby facilitating a low-cost design of the electrode sheet preparation device.

[0063] In some embodiments of the present application, as shown in Figure 3, the suction assembly may also include: a first lifting drive structure 20 and a fixed column 21, the first lifting drive structure 20 is arranged on the moving block, the lifting end of the first lifting drive structure 20 is fixed with a fixed column 21, and two adsorption structures are fixed on the fixed column 21.

[0064] Among them, as some embodiments of the present application, the first lifting drive structure 20 can be constructed as a drive motor. As some embodiments of the present application, the first lifting drive structure 20 can be constructed as a drive cylinder. Along the height direction of the electrode sheet preparation device, the first lifting drive structure 20 has two opposite ends, and one end of the first lifting drive structure 20 is provided on the moving block, so that the moving block can drive the first lifting drive structure 20 to move along the first direction. The end of the first lifting drive structure 20 away from the moving block is the lifting end, and the lifting end of the first lifting drive structure 20 is fixed with a fixed column 21. The two adsorption structures can be fixed to the fixed column 21 by, but not limited to, welding, bolts, etc., so that the lifting end of the first lifting drive structure 20 can drive the adsorption structure to move up and down along the height direction of the electrode sheet preparation device by driving the fixed column 21, thereby achieving the effect of moving the adsorption structure to a suitable height to smoothly adsorb the dry electrode film.

[0065] In some embodiments of the present application, as shown in Figure 6, the suction assembly may further include: a switching member 27, two air flow channels 211 are formed in the fixed column 21, the two air flow channels 211 are arranged along the first direction and spaced apart, the adsorption structure is constructed as an adsorption disk 26, the two adsorption structures are respectively connected to the two air flow channels 211, the switching member 27 is arranged in the fixed column 21 and is located between the two air flow channels 211, and the switching member 27 is controlled to be connected to one air flow channel 211 and disconnected from the other air flow channel 211 by moving the switching member 27 along the first direction, so as to control one adsorption structure to absorb the dry electrode film and the other adsorption structure to place the dry electrode film.

[0066] Two airflow channels 211 are formed within the fixed column 21. Along a first direction, the two airflow channels 211 are located near each end of the fixed column 21, and the two airflow channels 211 are spaced apart. The adsorption structure can be constructed as adsorption discs 26, with the two airflow channels 211 corresponding to the two adsorption discs 26, and the adsorption structure is connected to the corresponding airflow channels 211. A switching member 27 is disposed within the fixed column 21 and located between the two airflow channels 211, so that the switching member 27 can selectively connect to one airflow channel 211 and disconnect from the other airflow channel 211.

[0067] Specifically, the switching member 27 can be connected to the connecting tube 23, and the connecting tube 23 can be connected to the air source. When the switching member 27 moves along the first direction toward one of the air flow channels 211, the switching member 27 is connected to the air flow channel 211, and the switching member 27 is disconnected from the other air flow channel 211. When the switching member 27 moves along the first direction toward the other air flow channel 211, the switching member 27 is connected to the air flow channel 211, and the switching member 27 is disconnected from the other air flow channel 211. By controlling the switching member 27 to be connected to one air flow channel 211 and disconnected from the other air flow channel 211, the adsorption structure connected to the switching member 27 can be controlled to absorb the dry electrode membrane and the adsorption structure disconnected from the switching member 27 can be controlled to place the dry electrode membrane, thereby improving the stacking efficiency of the dry electrode membrane.

[0068] In some embodiments of the present application, as shown in Figure 5, a plurality of exhaust holes 25 are formed in the adsorption disk 26, and a plurality of jet channels 28 are formed at the adsorption end of the adsorption disk 26. The plurality of jet channels 28 extend radially along the adsorption disk 26. The plurality of exhaust holes 25 and the plurality of jet channels 28 correspond one to one, and the exhaust holes 25 connect the corresponding jet channels 28 and the corresponding airflow channels 211.

[0069] The multiple exhaust holes 25 and the multiple jet channels 28 can be evenly arranged along the circumference of the adsorption disk 26 to improve the stability of the dry electrode film absorption process and reduce the risk of failure of the dry electrode film absorption due to blockage of any exhaust hole 25 or jet channel 28. The multiple exhaust holes 25 and the multiple jet channels 28 correspond one to one, that is, one exhaust hole 25 corresponds to one jet channel 28, and the exhaust hole 25 connects the corresponding jet channel 28 and the corresponding air flow channel 211.

[0070] When one of the adsorption plates 26 moves to above the corresponding placement table 30, the switching member 27 moves along the first direction toward the adsorption plate 26, and the switching member 27 is connected to the air flow channel 211. At this time, the switching member 27, the air flow channel 211, the corresponding exhaust hole 25 and the corresponding jet channel 28 are all connected, so that the air flow can flow between the switching member 27, the air flow channel 211, the corresponding exhaust hole 25 and the corresponding jet channel 28, so that the adsorption plate 26 can adsorb the dry electrode membrane.

[0071] Another adsorption plate 26 moves to above the laminating body 40, and the switching member 27 is disconnected from the air flow channel 211 corresponding to this adsorption plate 26. At this time, the air flow is disconnected between the switching member 27 and the air flow channel 211, and there is no gas flowing in the corresponding exhaust hole 25 and the corresponding jet channel 28. This adsorption plate 26 no longer adsorbs the dry electrode membrane, and the dry electrode membrane falls into the laminating body 40 under the action of gravity, thereby achieving the effect of one adsorption plate 26 absorbing the dry electrode membrane and the other adsorption plate 26 stacking the dry electrode membrane working at the same time, thereby improving the stacking efficiency of the dry electrode membrane.

[0072] In some embodiments of the present application, as shown in Figure 6, a connecting channel is formed in the fixed column 21, and the connecting channel is located between the two air flow channels 211 and connects the two air flow channels 211. The switching member 27 extends along the first direction and is partially arranged in the connecting channel. A cavity for conveying air flow is formed in the switching member 27, and a connecting hole 271 connected to the cavity is opened on the side wall of the cavity near the end positions of the switching member 27 along the first direction. The switching member 27 is moved along the first direction so that the connecting hole 271 at one end of the switching member 27 is in the air flow channel 211 and the connecting hole 271 at the other end of the switching member 27 is in the connecting channel.

[0073] In particular, along the first direction, the connecting channel is located between the two airflow channels 211, and the two airflow channels 211 are connected through the connecting channel. The switching member 27 extends along the first direction, and a portion of the switching member 27 is disposed within the connecting channel. A cavity for conveying airflow is formed within the switching member 27. Along the first direction, the sidewalls of the cavity near the ends of the switching member 27 are provided with connecting holes 271 that communicate with the cavity. There are multiple connecting holes 271, which can connect the cavity with the corresponding airflow channel 211, so that airflow can flow between the switching member 27 and the corresponding airflow channel 211.

[0074] By moving the switching member 27 along the first direction, the connecting hole 271 located at one end of the switching member 27 is located in the air flow channel 211, and the connecting hole 271 located at the other end of the switching member 27 is located in the connecting channel. The connecting hole 271 located in the air flow channel 211 can be connected to the cavity and the corresponding air flow channel 211, and the connecting hole 271 located in the connecting channel is disconnected from the corresponding air flow channel 211, so as to disconnect the cavity and the corresponding air flow channel 211. At this time, the air flow flows between the cavity on the side of the connecting hole 271 located in the air flow channel 211, the air flow channel 211, the exhaust hole 25 and the jet channel 28, so that the corresponding adsorption plate 26 can adsorb the dry electrode membrane.

[0075] The airflow is disconnected between the cavity on one side of the connecting hole 271 in the connecting channel and the airflow channel 211, so that the corresponding adsorption plate 26 no longer adsorbs the dry electrode membrane. The dry electrode membrane falls into the laminating body 40 under the action of gravity, thereby achieving the effect of one adsorption plate 26 absorbing the dry electrode membrane and the other adsorption plate 26 stacking the dry electrode membrane working at the same time.

[0076] In some embodiments of the present application, as shown in FIG5 , the material suction assembly may further include: a connecting pipe 23 , the connecting pipe 23 being connected to the switching member 27 and communicating with the cavity.

[0077] Among them, the connecting pipe 23 is connected to the switching part 27, and the connecting pipe 23 is connected to the cavity, so that the airflow of the connecting pipe 23 can be continuously delivered to the cavity, so that the two adsorption plates 26 can be connected to the connecting pipe 23 in turn, thereby realizing one adsorption plate 26 adsorbing the dry electrode membrane and the other adsorption plate 26 stacking the dry electrode membrane, one adsorption plate 26 stacking the dry electrode membrane and the other adsorption plate 26 adsorbing the dry electrode membrane in a cyclical manner, thereby further improving the stacking efficiency of the dry electrode membrane.

[0078] In some embodiments of the present application, as shown in Figure 5, the suction assembly may also include: a driving member 24, a connecting pipe 23 is passed through the fixed column 21 and extends into the connecting channel, the connecting pipe 23 is fixedly connected to the switching member 27, the driving member 24 is fixed to the fixed column 21 and connected to the connecting pipe 23, and the driving member 24 drives the connecting pipe 23 to move along the first direction to move the switching member 27.

[0079] Among them, along the height direction of the electrode sheet preparation device, the connecting tube 23 can be passed through the upper side wall of the fixed column 21, and the connecting tube 23 extends into the connecting channel. As some embodiments of the present application, the connecting tube 23 is welded to the switching member 27. As some embodiments of the present application, the connecting tube 23 is connected to the switching member 27 by bolts. The driving member 24 can be, but is not limited to, constructed as a driving motor or a driving cylinder, etc. The driving member 24 can be, but is not limited to, fixed to the fixed column 21 by bolts, welding, etc., and the driving end of the driving member 24 is connected to the connecting tube 23, so that the driving end of the driving member 24 can move along the first direction by driving the connecting tube 23, and the connecting tube 23 drives the switching member 27 to move along the first direction, so as to achieve the effect of indirectly driving the switching member 27 to move along the first direction, thereby achieving the effect of controlling the connection or disconnection of the cavity of the switching member 27 with the corresponding air flow channel 211.

[0080] In some embodiments of the present application, as shown in FIG. 5 , an extension structure 22 protruding from the fixing post 21 is formed on the outer peripheral wall of the fixing post 21 , and the driving member 24 is fixed to the extension structure 22 .

[0081] Among them, the fixed column 21 is formed with an extension structure 22, and the extension structure 22 can be annular. The extension structure 22 is formed on the outer peripheral wall of the fixed column 21 and protrudes from the fixed column 21. Such an arrangement can make the extension structure 22 be set outside the air flow channel 211 and the connecting channel of the fixed column 21, reducing the risk of the driving member 24 interfering with the air flow circulation, and the extension structure 22 can provide an assembly position for the driving member 24. By fixing the driving member 24 to the extension structure 22, further, the driving member 24 is fixed in the extension structure 22, which can reduce the interference of the external environment on the driving member 24, which is beneficial to improving the working stability of the driving member 24, thereby extending the service life of the driving member 24.

[0082] In some embodiments of the present application, as shown in Figure 6, the connecting channel includes a movable channel 213 and two connecting channels 212, the movable channel 213 is located between the two connecting channels 212 and connects the two connecting channels 212, the two connecting channels 212 are arranged along the first direction and are located between the two air flow channels 211, the cross-sectional size of the movable channel 213 is larger than the cross-sectional size of the connecting channel 212, and the outer peripheral wall of the switching member 27 is provided with two limiting rings 273, the two limiting rings 273 are located in the movable channel 213 and arranged along the first direction.

[0083] In the first direction, the two connecting channels 212 are respectively located at the two ends of the connecting channel, and the movable channel 213 is located between the two connecting channels 212. In other words, the connecting channels 212, the movable channel 213, and the connecting channels 212 are arranged in sequence along the first direction. The movable channel 213 connects the two connecting channels 212. The two connecting channels 212 are arranged in the first direction and are located between the two airflow channels 211. In other words, the airflow channels 211, the connecting channels 212, the movable channel 213, the connecting channels 212, and the airflow channels 211 are arranged in sequence along the first direction.

[0084] The cross-sectional dimensions of the movable channel 213 are greater than those of the connecting channel 212, so that limiting bosses are formed between the movable channel 213 and the connecting channels 212 on both sides. Two limiting rings 273 are provided on the outer peripheral wall of the switching member 27. The two limiting rings 273 can be fixed to the outer peripheral wall of the switching member 27 by, but are not limited to, welding. The two limiting rings 273 are both located within the movable channel 213, and the two limiting rings 273 are arranged along the first direction. When the switching member 27 moves along the first direction, the two limiting rings 273 respectively abut against the corresponding limiting bosses to limit excessive movement of the switching member 27, thereby reducing the risk of damage to the connecting tube 23 caused by collision between the connecting tube 23 and the outer peripheral wall of the fixed column 21 when the driving member 24 drives the connecting tube 23, thereby reducing the risk of failure of the suction assembly, which is conducive to extending the service life of the electrode sheet preparation device.

[0085] In some embodiments of the present application, as shown in FIG6 , the switching member 27 is sleeved with a sealing ring 272 , and each communicating hole 271 is provided with a sealing ring 272 on both sides along the first direction, and the sealing ring 272 is suitable for abutting against the inner wall of the connecting channel.

[0086] In some embodiments of the present application, the sealing ring 272 may be made of rubber. In some embodiments of the present application, the sealing ring 272 may be made of felt. A plurality of sealing rings 272 may be provided, and the plurality of sealing rings 272 are all sleeved on the outer peripheral wall of the switching member 27. Along the first direction, sealing rings 272 are provided on both sides of each connecting hole 271. When the switching member 27 moves along the first direction, the connecting hole 271 on one side and the sealing rings 272 on both sides of the connecting hole 271 are all moved into the air flow channel 211, and the sealing ring 272 is separated from the inner wall of the connecting channel. The connecting hole 271 connects the cavity with the corresponding air flow channel 211, so that the adsorption disk 26 on this side can adsorb the dry electrode membrane.

[0087] The connecting hole 271 on the other side and the sealing rings 272 on both sides of the connecting hole 271 are moved into the connecting channel 212. The sealing ring 272 abuts against the inner wall of the connecting channel. The adsorption disk 26 on this side no longer adsorbs the dry electrode membrane. The dry electrode membrane falls into the laminating body 40 under the action of gravity, realizing the stacking effect of the dry electrode membrane. By setting the sealing ring 272, the gap between the cavity and the corresponding airflow channel 211 can be reliably sealed, reducing the risk of dry electrode membrane adsorption or stacking failure due to airflow leakage, thereby improving the working stability of the electrode sheet preparation device.

[0088] In some embodiments of the present application, as shown in FIG. 7 , the electrode sheet preparation device may further include: a second lifting drive structure 42 , which is connected between the pressing head 41 and the top wall of the fixing frame 10 .

[0089] Wherein, as some embodiments of the present application, the second lifting drive structure 42 can be constructed as a drive motor. As some embodiments of the present application, the second lifting drive structure 42 can be constructed as a drive cylinder. The second lifting drive structure 42 is connected between the pressure head 41 and the top wall of the fixed frame 10. Further, along the height direction of the electrode sheet preparation device, the second lifting drive structure 42 can have two opposite ends, and the output end of the second lifting drive structure 42 is connected to the pressure head 41 to control the lifting and lowering of the pressure head 41 along the electrode sheet preparation device, so that the pressure head 41 can press the stacked current collector and dry electrode film to form an electrode sheet. The side of the second lifting drive structure 42 away from the output end can be fixedly connected to the top wall of the fixed frame 10 by, but not limited to, welding, bolts, etc., to improve the working stability of the second lifting drive structure 42, which is beneficial for the second lifting drive structure 42 to reliably drive the pressure head 41 and achieve the effect of smoothly pressing the electrode sheet.

[0090] In some embodiments of the present application, as shown in FIG3 , a movable track 12 is fixedly provided on the bottom wall of the fixing frame 10 , and the laminating machine body 40 is movably disposed on the movable track 12 .

[0091] The fixed frame 10 is provided with a movable track 12. The movable track 12 is arranged on the bottom wall of the fixed frame 10 along the height direction of the electrode sheet preparation device. The movable track 12 extends along the second direction. The laminating machine body 40 is movably arranged on the movable track 12 so that the laminating machine body 40 can be selectively moved along the second direction to below the pressure head 41 or below the linear module 11. When the dry electrode film and the current collector need to be stacked in the laminating machine body 40, the laminating machine body 40 is moved along the second direction to below the linear module 11 to complete the stacking of multiple layers of dry electrode film, current collector, and multiple layers of dry electrode film in sequence. The laminating body 40 drives the stacked multi-layer dry electrode membrane, current collector and multi-layer dry electrode membrane to move along the second direction to the bottom of the pressure head 41 through the moving track 12. The pressure head 41 descends under the action of the second lifting drive structure 42 to press the electrode sheet. After the electrode sheet is pressed, the laminating body 40 continues to move along the second direction to the bottom of the linear module 11 through the moving track 12 for stacking again, and the cycle is repeated to achieve the effect of continuous processing of the electrode sheet.

[0092] In some embodiments of the present application, as shown in Figures 7 and 8, a groove 1 401 is formed on the upper end surface of the laminating body 40, and a groove 2 411 corresponding to the groove 1 401 is formed on the lower end surface of the pressure head 41. The pressure head 41 is driven to move downward so that the edges of the dry electrode membranes on both sides of the current collector of the electrode sheet abut against each other.

[0093] The laminating body 40 is formed with a groove 1 401 , which is formed on the upper end surface of the laminating body 40 and is recessed inwardly of the laminating body 40 . The dry-process electrode membrane and current collector are stacked within groove 1 401 , facilitating accurate stacking. The lower end surface of the pressing head 41 is formed with a groove 2 411 , which corresponds to groove 1 401 . The dimensions and shapes of groove 1 401 and groove 2 411 are adapted. When the second lifting drive structure 42 drives the pressing head 41 downward, the current collector is disposed in the space between groove 1 401 and groove 2 411 , reducing the risk of the pressing head 41 damaging the electrode sheet. The size of the dry electrode membrane can be larger than the size of the current collector so that the outer edges of the dry electrode membrane on both sides of the current collector can abut under the pressing action of the pressure head 41. The size of the dry electrode membrane can be equal to the size of the current collector so that the outer edges of the dry electrode membrane on both sides of the current collector can first extend and then abut under the pressing action of the pressure head 41, so that the dry electrode membrane can cover the current collector, reduce the risk of defects such as burrs on the electrode sheet, and thus improve the safety performance of the battery cell.

[0094] In some embodiments of the present application, as shown in FIG8 , a tab placement groove 402 adjacent to and in communication with the groove 1 401 is further formed on the upper end surface of the laminating body 40 .

[0095] Among them, the upper end surface of the laminating body 40 is also formed with a tab placement groove 402. The tab placement groove 402 is adjacent to the groove 1 401. When the current collector is placed in the groove 1 401, the tab placement groove 402 can be used to place the tab of the current collector, thereby reducing the risk of damage to the current collector caused by interference between the tab and the sidewall of the groove 1 401. Furthermore, two tab placement grooves 402 can be provided. Since the tab is provided near one end of the current collector, by providing two tab placement grooves 402, the current collector can be smoothly placed in the laminating body 40 regardless of whether the current collector is placed upright or inverted, which is beneficial to improving the use efficiency of the laminating body 40.

[0096] As shown in Figure 9, the electrode sheet according to the embodiment of the present application is prepared according to the electrode sheet preparation method of the above embodiment. The electrode sheet may include: a current collector and a multilayer dry electrode film, the current collector and the multilayer dry electrode film are stacked, the current collector has a first side and a second side relative to each other, the first side and the second side are both provided with a multilayer dry electrode film, and the multilayer dry electrode film located on the same side of the current collector is placed alternately in front and back relative to the current collector.

[0097] Among them, the current collector and the multi-layer dry electrode film are stacked. Along the thickness direction of the current collector, the current collector has a first side and a second side relative to each other. The first side and the second side are both provided with a multi-layer dry electrode film, and the multi-layer dry electrode film located on the same side of the current collector is placed alternately in front and back relative to the current collector, reducing the risk of uneven thickness of the electrode sheet, thereby improving the flatness of the electrode sheet after lamination, and can also reduce the risk of defects such as burrs on the electrode sheet, thereby improving the safety performance of the battery cell.

[0098] According to the battery cell of the embodiment of the present application, including the electrode sheet of the above embodiment, by arranging two placement platforms 30 on either side of the laminating machine body 40, and placing the dry electrode films on the two placement platforms 30 in opposite directions, the two adsorption structures can sequentially absorb the dry electrode films on the corresponding placement platforms 30, and the dry electrode films on the corresponding placement platforms 30 can be sequentially stacked on the current collector. This allows the multi-layer dry electrode films to be placed alternately in front and back relative to the current collector, reducing the risk of uneven thickness of the electrode sheets, thereby improving the flatness of the laminated electrode sheets, and reducing the risk of defects such as burrs on the electrode sheets, thereby improving the safety performance of the battery cell.

[0099] According to an embodiment of the present application, the battery device includes the battery cell of the above embodiment. By arranging two placement platforms 30 on either side of a laminating machine body 40, with the dry electrode films placed in opposite directions on the two placement platforms 30, the two adsorption structures can sequentially absorb the dry electrode films on the corresponding placement platforms 30 and sequentially stack the dry electrode films on the corresponding placement platforms 30 on the current collector. This allows the multiple layers of dry electrode films to be placed alternately in front and back relative to the current collector, reducing the risk of uneven thickness of the electrode sheets, thereby improving the flatness of the laminated electrode sheets, reducing the risk of defects such as burrs on the electrode sheets, and improving the safety performance of the battery cells, thereby improving the safety performance of the battery device.

[0100] Example 1

[0101] The electrode sheet preparation method comprises the following steps:

[0102] The first electrode film layer, the current collector, and the second electrode film layer are placed in a laminator in this order and pressed into shape, so that the first electrode film layer and the second electrode film layer on both sides of the current collector cover the edge of the current collector to obtain a dry-process positive / negative electrode sheet;

[0103] The first electrode film layer is obtained by alternately stacking m layers on the front and back of the dry electrode film, and the second electrode film layer is obtained by alternately stacking n layers on the front and back of the dry electrode film. The size of the current collector is not larger than the size of the dry electrode film, m≥2, n≥2, and are integers.

[0104] The dry-process electrode films on the same side of the current collector are placed in sequence on the front and back sides, which can eliminate the uneven thickness of the electrode film that occurs during the rolling process, so that the upper end face or the lower end face of the electrode sheet is on the same horizontal plane, and there will be no obvious depressions, bulges, etc., which improves the safety performance of the electrode sheet. The electrode film size is greater than or equal to the current collector size. During the lamination process, referring to Figure 7, the first electrode film layer or the second electrode film layer can be uniformly deformed and extended toward the edge to cover the cut edge of the current collector to eliminate the influence of burrs. At the same time, alternating the front and back of the electrode film can effectively eliminate the problem of uneven deformation and extension caused by excessive thickness or thinness in local areas during the stacking of the electrode film only on the front or back, and the inability to cover the cut edge of the current collector. If m≠n, then the m≠n of the corresponding negative or positive electrode sheet; if m=n, then the m=n of the corresponding negative or positive electrode sheet; the current collector material is aluminum foil or copper foil.

[0105] Example 2

[0106] An electrode sheet preparation device, comprising:

[0107] A fixed frame 10, wherein a linear module 11 is provided on the top of the fixed frame 10, and the linear module 11 has a moving block that can move linearly;

[0108] The laminator is disposed in the fixing frame 10 and includes a laminator body 40 disposed at the bottom of the fixing frame 10 and a pressing head 41 disposed at the top of the fixing frame 10 and away from one end of the linear module 11;

[0109] The placement table 30 is disposed on the fixing frame 10 and is located on both sides of the laminating machine body 40 .

[0110] The material suction component includes a first lifting drive structure 20 arranged on the moving block and a fixed column 21 arranged at the telescopic end of the first lifting drive structure 20, air flow channels 211 are provided on both sides of the fixed column 21, and adsorption plates 26 connected to the corresponding air flow channels 211 are provided on both sides of the bottom of the fixed column 21. A switching member is provided between the two groups of air flow channels 211 to drive the switching member to move and control the switching member to be connected or disconnected with the air flow channel 211, thereby controlling one group of the adsorption plates 26 to absorb the electrode membrane and the other group of the adsorption plates 26 to place the electrode membrane.

[0111] Specifically, the cut electrode film is placed with its front side facing upward on one of the placement tables 30, and the electrode film is placed with its front side facing downward on the other placement table 30. The suction component is used to allow the electrode films on the two groups of placement tables 30 to be alternately stacked on the laminating body 40. First, through the cooperation of the linear module 11, one group of adsorption plates 26 can be located directly above the placement table 30, and the adsorption plates 26 on the other side can be located directly above the laminating body 40. The first lifting drive structure 20 pushes the fixed column 21 to move downward. When the electrode film on the placement table 30 needs to be adsorbed and the electrode film on the laminating body 40 needs to be placed, the switching member moves, and the switching member is disconnected from the air flow channel 211 above the laminating body 40, so that the electrode film adsorbed on the lower end face of the adsorption plate 26 connected to the air flow channel 211 can be detached, thereby making the switch The component is connected to another group of air flow channels 211 to adsorb the electrode film on the placement table 30. At this time, the first lifting drive structure 20 pushes the fixed column 21 to move upward, and then the linear module drives the fixed column 21 to move, so that the adsorption plate 26 without the electrode film moves to another group of placement tables 30, and the adsorption plate 26 adsorbed with the electrode film moves to the top of the laminating body 40. Repeating the above operation can make the electrode membranes on the two groups of placement tables 30 alternately stacked, and the electrode membranes on the two groups of placement tables 30 can be placed alternately front and back. Stacking the front and back of the electrode membrane can eliminate the problem of uneven thickness of the electrode sheet caused by uneven thickness of the electrode membrane during the rolling process, and then place the cut current collector on the multilayer electrode membrane, and then use the suction component to alternately stack the front and back of the multilayer electrode membrane on the current collector, and press it into shape through the cooperation of the laminating body 40 and the pressure head 41.

[0112] In order to reduce the damage to the surface of the electrode membrane by the adsorption disk 26 during the adsorption process, referring to Figures 3, 5 and 6, a plurality of exhaust holes 25 are provided in the adsorption disk 26, and a jet channel 28 is provided on the bottom end surface of the adsorption disk 26, which is connected to the exhaust holes 25 in a one-to-one correspondence. Specifically, when the electrode membrane on the placement table 30 needs to be adsorbed and the electrode membrane on the laminating body 40 needs to be placed, the switching member moves, and the switching member is disconnected from the airflow channel 211 above the laminating body 40, which has formed a high-pressure gas exhaust channel, and the jet channel 28 is connected to the external environment, so that the airflow channel 211 connected to the airflow channel 211 is connected to the external environment. The electrode film adsorbed on the lower end surface of the adsorption plate 26 can be detached, and the switching component is connected to another set of air flow channels 211 to form a high-pressure gas exhaust channel. The high-pressure gas in the adsorption plate 26 enters the jet channel 28 through the exhaust hole 25 to form a high-speed jet, and then is discharged from the outer edge of the bottom surface of the adsorption plate 26, taking away the air at the bottom of the adsorption plate 26 to form a negative pressure area, thereby adsorbing the electrode film on the placement table 30, and using air flow to generate suction instead of directly applying high pressure, low pressure or vacuum for adsorption, which can better protect the surface of the electrode membrane and reduce damage to the surface of the electrode membrane. The switching component is connected to the air compressor.

[0113] In one embodiment, referring to Figure 6, the switching member includes a switching member 27 movably arranged inside the fixed column 21, the switching member 27 has a cavity for conveying airflow, both ends of the switching member 27 extend into the corresponding airflow channel 211, and the side walls of the switching member 27 are provided with connecting holes 271 near the end positions of both ends. A moving channel 213 is provided in the fixed column 21 and located in the middle position. A connecting pipe 23 is provided on the top of the switching member 27 and located in the moving channel 213. An extension structure 22 is provided at the center of the top of the fixed column 21. The top of the connecting pipe 23 passes through the side wall of the fixed column 21 and extends into the extension structure 22. The side wall of the extension structure 22 is provided with a driving member 24. The telescopic end of the driving member 24 is detachably connected to the connecting pipe 23. A connecting channel 212 is provided between the moving channel 213 and the air flow channel 211. The driving member 24 pushes the switching member 27 to move, so that the connecting hole 271 at one end of the switching member 27 is in the air flow channel 211 and the connecting hole 271 at the other end of the switching member 27 is in the connecting channel 212. Specifically, the driving member 24 pushes the switching member 27 to move, so that the connecting hole 271 at one end of the switching member 27 enters the air flow channel 211, so that the air flow channel 211 and the switching member form a complete high-pressure gas exhaust channel to adsorb the electrode membrane, and the connecting hole 271 at the other end of the switching member 27 moves into the connecting channel 212 and is disconnected from the corresponding air flow channel 211. Therefore, the adsorption plate 26 corresponding to the air flow channel can be detached from the electrode membrane, so that the electrode membrane is stacked on the laminating body 40.

[0114] In order to prevent the communicating hole 271 entering the communicating channel 212 from affecting the airflow pressure inside the switching member 27, referring to Figures 3 and 4, the surface of the switching member 27 and on both sides of the communicating hole 271 are inlaid with sealing rings 272, and the circumferential surface of the switching member 27 and located in the moving channel 213 are provided with two groups of limiting rings 273, the diameter of the limiting ring 273 is larger than the diameter of the communicating channel 212, and the diameter of the moving channel 213 is larger than the diameter of the limiting ring 273. The two groups of sealing rings 272 form a closed area around the communicating hole 271 under the cooperation of the inner wall of the communicating channel 212, and the problem of pressure relief will not occur, and the normal operation of the other group of communicating holes 271 will not be affected. At the same time, the limiting ring 273 can seal the communicating channel 212 that forms the high-pressure gas discharge channel, effectively avoiding the problem of pressure relief.

[0115] In one embodiment, referring to Figures 7 and 8, a second lifting drive structure 42 is fixedly provided between the pressure head 41 and the fixed frame 10, the upper end surface of the laminating machine body 40 is provided with a groove 1 401, and the lower end surface of the pressure head 41 is provided with a groove 2 411. The pressure head 41 is driven to move downward to control the edges of the electrode film on the upper and lower end surfaces of the current collector to be coated on both sides of the current collector. Specifically, the electrode sheet of the first electrode film layer, the current collector, and the second electrode film layer is formed on the laminating machine body 40. The laminating machine body 40 is driven to move so that the laminating machine body 40 moves to the bottom of the pressure head 41, and the pressure head 41 is driven to move downward so that the pressure head 41 moves downward to extrude the dry positive / negative electrode sheet. During the extrusion process, the pressure head 41 is pressed Groove 2 411 can squeeze the edge of the first electrode film layer on the upper end face of the current collector so that it is covered on both sides of the current collector. Similarly, in the process of the pressure head 41 moving downward, the edge of the second electrode film layer on the lower end face of the current collector is pushed toward the current collector with the cooperation of groove 1 401, so that it is covered on both sides of the current collector. The electrode film will cover the edge of the current collector and eliminate the influence of burrs. The heating temperature of the pressure head 41 is 100-300℃, the pressure is 0.1-500MPa, and the holding time is 0.1-10min. The width of groove 1 401 and groove 2 411 is greater than the width of the current collector, and the width of the electrode film is greater than the width of groove 1 401 and groove 2 411.

[0116] In order to move the laminating body 40, referring to Figures 3, 5 and 7, a movable track 12 is provided at the bottom of the fixed frame 10, and the laminating body 40 is set on the movable track 12. When it is necessary to stack the electrode film in the laminating body 40, the laminating body 40 is moved to the center position between the two groups of placement tables 30. When the electrode sheets are stacked, the laminating body 40 is moved to the bottom of the pressing head 41 for pressing.

[0117] In one embodiment, referring to Figures 7 and 8, two sets of tab placement grooves 402 are provided on the upper end surface of the laminate body 40 and at one end of the groove 1 401. When pressed into a battery cell, the tabs of different electrode sheets are pressed, and the combination is more firm due to the intermolecular bonding force, which can reduce the occurrence of cold solder joints.

[0118] Example 3

[0119] An electrode sheet is prepared according to the preparation method of Example 1.

[0120] Example 4

[0121] A high-power soft-pack lithium-ion battery includes the electrode sheet described in the third embodiment.

[0122] The negative electrode sheet, the separator and the positive electrode sheet are stacked L times in the order of L≥1 and are an integer. The sheets are placed in a laminating machine 40 and heated to a temperature of 100-300°C, a pressure of 0.1-500MPa and a holding time of 0.1-10min to obtain a cell and then a battery. Since the laminating machine 40 is provided with a tab placement groove 402, when the tabs of different electrode sheets are pressed, the binding is more secure due to the intermolecular binding force, which can reduce the occurrence of cold solder joints.

[0123] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0124] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for preparing an electrode sheet, wherein: include: Cutting the dry electrode film material to form a dry electrode film; Cutting the current collector material to form a current collector, wherein the size of the current collector is smaller than or equal to the size of the dry electrode film; The plurality of dry electrode films, the current collector and the plurality of dry electrode films are stacked in this order and then pressed to form an electrode sheet, and the plurality of dry electrode films on the same side of the current collector are alternately placed in a positive and negative direction relative to the current collector.

2. The method for preparing an electrode sheet according to claim 1, wherein: The current collector is provided with a tab.

3. An electrode sheet preparation device, wherein: include: A fixed frame (10), wherein a top wall of the fixed frame (10) is provided with a linear module (11), and the linear module (11) has a moving block movable along a first direction; A laminator, the laminator being arranged in the fixed frame (10), the laminator comprising a laminator body (40) and a pressing head (41), the laminator body (40) being movably arranged on the bottom wall of the fixed frame (10), the pressing head (41) being arranged on the top wall of the fixed frame (10), the pressing head (41) being located on one side of the linear module (11) along a second direction, the laminator body (40) being selectively moved below the pressing head (41), the first direction, the second direction and the height direction of the electrode sheet preparation device being perpendicular to each other; Two placement tables (30), along the first direction, the two placement tables (30) are arranged in the fixing frame (10) and on the bottom wall of the fixing frame (10), and the two placement tables (30) are respectively arranged on both sides of the laminating machine body (40); A suction component is connected to the moving block, and drives the suction component to move when the moving block moves. The suction component includes two adsorption structures, and the two adsorption structures can be raised and lowered along the height direction of the electrode sheet preparation device. The two adsorption structures are arranged along the first direction, and the adsorption structures are used to selectively absorb the dry electrode film of the electrode sheet.

4. The electrode sheet preparation device according to claim 3, wherein: Along the first direction, the laminating machine body (40) and the two placement tables (30) are spaced at the same distance.

5. The electrode sheet preparation device according to claim 3 or 4, wherein: The laminating machine body (40) is movably arranged on the fixing frame (10) along the second direction.

6. The electrode sheet preparation device according to any one of claims 3 to 5, wherein: The material suction component further comprises: a first lifting drive structure (20) and a fixed column (21); the first lifting drive structure (20) is arranged on the moving block; the lifting end of the first lifting drive structure (20) is fixedly provided with the fixed column (21); and the two suction structures are fixedly provided on the fixed column (21).

7. The electrode sheet preparation device according to claim 6, wherein: The suction component further includes: a switching member (27); two air flow channels (211) are formed in the fixed column (21); the two air flow channels (211) are arranged along the first direction and spaced apart; the adsorption structure is constructed as an adsorption disk (26); the two adsorption structures are respectively connected to the two air flow channels (211); the switching member (27) is provided in the fixed column (21) and is located between the two air flow channels (211); the switching member (27) is controlled to be connected to one air flow channel (211) and disconnected from the other air flow channel (211) by moving the switching member (27) along the first direction, so as to control one adsorption structure to absorb the dry electrode film and the other adsorption structure to place the dry electrode film.

8. The electrode sheet preparation device according to claim 7, wherein: The adsorption disk (26) is formed with a plurality of exhaust holes (25), and the adsorption end of the adsorption disk (26) is formed with a plurality of jet channels (28), and the plurality of jet channels (28) extend along the radial direction of the adsorption disk (26). The plurality of exhaust holes (25) and the plurality of jet channels (28) correspond one to one, and the exhaust holes (25) are connected to the corresponding jet channels (28) and the corresponding air flow channels (211).

9. The electrode sheet preparation device according to claim 8, wherein: A connecting channel is formed in the fixed column (21), and the connecting channel is located between the two air flow channels (211) and connects the two air flow channels (211). The switching member (27) extends along the first direction and is partially arranged in the connecting channel. A cavity for conveying air flow is formed in the switching member (27), and a connecting hole (271) connected to the cavity is opened on the side wall of the cavity at a position close to the end of each end of the switching member (27) along the first direction. When the switching member (27) moves along the first direction, the connecting hole (271) located at one end of the switching member (27) is located in the air flow channel (211) and the connecting hole (271) located at the other end of the switching member (27) is located in the connecting channel.

10. The electrode sheet preparation device according to claim 9, wherein: The material suction assembly further comprises a connecting pipe (23), wherein the connecting pipe (23) is connected to the switching member (27) and communicates with the cavity.

11. The electrode sheet preparation device according to claim 10, wherein: The material suction assembly further includes: a driving member (24); the connecting pipe (23) is passed through the fixed column (21) and extends into the connecting channel; the connecting pipe (23) is fixedly connected to the switching member (27); the driving member (24) is fixed to the fixed column (21) and connected to the connecting pipe (23); the driving member (24) drives the connecting pipe (23) to move along the first direction to move the switching member (27).

12. The electrode sheet preparation device according to claim 11, wherein: An extension structure (22) protruding from the fixing column (21) is formed on the outer peripheral wall of the fixing column (21), and the driving member (24) is fixed to the extension structure.

13. The electrode sheet preparation device according to any one of claims 9 to 12, wherein: The connecting channel comprises a moving channel (213) and two communicating channels (212); the moving channel (213) is located between the two communicating channels (212) and connects the two communicating channels (212); the two communicating channels (212) are arranged along the first direction and are located between the two air flow channels (211); the cross-sectional dimension of the moving channel (213) is greater than the cross-sectional dimension of the communicating channels (212); the outer peripheral wall of the switching member (27) is provided with two limiting rings (273); the two limiting rings (273) are located in the moving channel (213) and are arranged along the first direction.

14. The electrode sheet preparation device according to any one of claims 9 to 13, wherein: The switching member (27) is sleeved with a sealing ring (272), and each of the communicating holes (271) is provided with the sealing ring (272) on both sides along the first direction, and the sealing ring (272) is suitable for abutting against the inner wall of the connecting channel.

15. The electrode sheet preparation device according to any one of claims 3 to 14, wherein: Also includes: A second lifting drive structure (42), wherein the second lifting drive structure (42) is connected between the pressing head (41) and the top wall of the fixing frame (10).

16. The electrode sheet preparation device according to any one of claims 3 to 15, wherein: A movable track (12) is fixedly provided on the bottom wall of the fixed frame (10), and the laminating machine body (40) is movably arranged on the movable track (12).

17. The electrode sheet preparation device according to any one of claims 3 to 16, wherein: The upper end surface of the laminating body (40) is formed with a groove 1 (401), and the lower end surface of the pressure head (41) is formed with a groove 2 (411) corresponding to the groove 1 (401). The pressure head (41) is driven to move downward so that the edges of the dry electrode membrane on both sides of the current collector of the electrode sheet are abutted.

18. The electrode sheet preparation device according to claim 17, wherein: The upper end surface of the laminating body (40) is also formed with a tab placement groove (402) adjacent to and connected to the groove 1 (401).

19. An electrode sheet, wherein: The electrode sheet preparation method according to claim 1, wherein the electrode sheet comprises: A current collector and a multilayer dry electrode film, wherein the current collector and the multilayer dry electrode film are stacked, the current collector has a first side and a second side relative to each other, the first side and the second side are both provided with a multilayer dry electrode film, and the multilayer dry electrode film located on the same side of the current collector is placed alternately in front and back relative to the current collector.

20. A battery cell, wherein: Comprising the electrode sheet according to claim 19.

21. A battery device, wherein: Comprising the battery cell according to claim 20.

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