Pole piece, battery and electric equipment

Abstract

The utility model discloses a pole piece which is formed by cutting a sheet material by a laser cutting device, and at most one side of the pole piece is flush with one side of the sheet material. Single-station one-time cutting forming of the pole piece is achieved through the laser cutting equipment, the formed pole piece has higher precision, the pole piece production efficiency is improved, physical cutters are not needed, cutter abrasion and replacement cost are avoided, the long-term use cost is lower, the manufacturing cost is reduced, the product competitiveness is improved, the number of used equipment is small, and the production cost is low. The occupied space of equipment is saved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of machining, especially to a pole piece, a battery and an electric device. BACKGROUND

[0002] The laminated battery has the characteristics of high energy density, high power density and long service life, and is often used in watches, mobile phones and new energy vehicles and other products. In the production process of the laminated battery, the sheet material is first made into a single pole piece, and then the pole piece is stacked, hot-pressed, assembled and other processes to prepare a battery and an electric device.

[0003] In related technologies, the sheet material is usually cut into a single pole piece by laser cutting or hardware cutters or a combination of the two, for example, hardware cutter punching, mainly including full-size hardware cutter punching and hardware cutter punching tab shape + hardware cutting two sheet making methods; laser cutting + hardware cutting, the tab edge shape is punched by a hardware cutter, and the continuously formed pole piece is then cut open by a hardware cutter; laser cutting forming, including two methods, laser cutting tab shape + laser cutting, and laser cutting full-size pole piece.

[0004] However, the above cutting method adopts two-step forming, and the transmission between different positions increases the error of pole piece cutting, resulting in a decrease in the forming precision of the pole piece. UTILITY MODEL CONTENTS

[0005] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides a pole piece, which is cut into a single piece by a laser cutting device, and the formed pole piece has higher precision.

[0006] The utility model further provides a battery.

[0007] The utility model further provides an electric device.

[0008] According to the pole piece of the first aspect of the utility model, the pole piece is cut from a sheet material by a laser cutting device, and the pole piece is flush with one side of the sheet material.

[0009] According to the pole piece of the utility model, the pole piece is cut into a single piece by a laser cutting device, the formed pole piece has higher precision, the efficiency of producing the pole piece is improved, no physical cutter is used, there is no cutter wear and replacement cost, the cost is lower under long-term use conditions, the manufacturing cost is reduced, the competitiveness of the product is improved, and fewer devices are used, saving device space.

[0010] According to some embodiments of the present application, the upper side of the pole piece is flush with the upper side of the sheet; or, the lower side of the pole piece is flush with the lower side of the sheet; or, the upper side and the lower side of the pole piece are both not flush with the upper side and the lower side of the sheet.

[0011] According to some embodiments of the present application, the pole piece comprises: a hollow foil area and a tab area, the hollow foil area and the tab area are connected to each other; wherein the side of the hollow foil area away from the tab area is flush with the lower side of the sheet; or, the side of the hollow foil area away from the tab area is flush with the upper side of the sheet; or, the side of the hollow foil area away from the tab area and the tab area are both not flush with the upper side and the lower side of the sheet.

[0012] According to some embodiments of the present application, a heat affected zone is formed at the edge of the pole piece, the size of the heat affected zone is h, h satisfies the relationship: 10um≤h≤200um.

[0013] According to some embodiments of the present application, the edge of one of the pole pieces coincides with the edge of the other pole piece.

[0014] According to some embodiments of the present application, the sheet is arranged between the edge of one of the pole pieces and the edge of the other pole piece.

[0015] The battery according to the second aspect of the present application comprises the pole pieces cut by the pole piece cutting device, the pole pieces comprise: positive pole pieces and negative pole pieces; a plurality of separators, the plurality of separators are respectively arranged between adjacent positive pole pieces and negative pole pieces.

[0016] According to some embodiments of the present application, on one side in any direction, the size of the protrusion of the separator relative to the negative pole piece is L1, L1 satisfies the relationship: 0.5mm≤L1≤1.3mm.

[0017] According to some embodiments of the present application, on one side in any direction, the size of the protrusion of the negative pole piece relative to the positive pole piece is L2, L2 satisfies the relationship: 0.25mm≤L2≤0.45mm.

[0018] The electric device according to the third aspect of the present application comprises the battery.

[0019] The additional aspects and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, with reference to the following drawings in which:

[0021] Figure 1 is a partial view of a pole piece cutting device according to an embodiment of the present application;

[0022] Figure 2 is an embodiment of cooperation of a dust removal cover, a cutting plate and a blowing device according to an embodiment of the present application;

[0023] Figure 3 is a structural schematic view of a cutting plate according to an embodiment of the present application;

[0024] Figure 4 is a sectional view of a dust removal cover, a cutting plate and a blowing device according to an embodiment of the present application;

[0025] Figure 5 is another embodiment of cooperation of a dust removal cover and a cutting plate according to an embodiment of the present application;

[0026] Figure 6 is a structural schematic view of a battery according to an embodiment of the present application;

[0027] Figure 7 is Figure 6 is a partial view of a laser device cutting path according to an embodiment of the present application;

[0028] Figure 8 is an embodiment one of a laser device cutting path according to an embodiment of the present application;

[0029] Figure 9 is an embodiment two of a laser device cutting path according to an embodiment of the present application;

[0030] Figure 10 is an embodiment three of a laser device cutting path according to an embodiment of the present application;

[0031] Figure 11 is an embodiment four of a laser device cutting path according to an embodiment of the present application;

[0032] Figure 12 is an embodiment five of a laser device cutting path according to an embodiment of the present application;

[0033] Figure 13 is an embodiment six of a laser device cutting path according to an embodiment of the present application;

[0034] Figure 14 is a sectional view of different pole piece forming methods.

[0035] Reference signs:

[0036] 10, sheet; 20, cutting plate; 21, cutting groove; 30, dust removal cover; 31, suction port; 40, blowing device; 41, air knife; 42, blowing pipeline; 51, suction port; 60, battery; 61, positive plate; 62, negative plate; 63, diaphragm; 70, pole piece; 71, empty foil area; 72, tab area. DETAILED DESCRIPTION

[0037] The embodiments of the utility model are described in detail below, and the embodiments described with reference to the drawings are exemplary, and the embodiments of the utility model are described in detail below.

[0038] The embodiments of the utility model are described in detail below, and the embodiments described with reference to the drawings are exemplary, and the embodiments of the utility model are described in detail below. Figures 1-13 The pole piece 70 according to the embodiments of the utility model is described below, and the utility model further proposes a battery 60, and further, the utility model further proposes a power utilization equipment.

[0039] The pole piece 70 of the embodiments of the utility model is cut from the sheet 10 by the laser cutting device.

[0040] Specifically, referring to Figure 1-5 The pole piece cutting equipment includes a rack, a sheet 10, a cutting table and a laser cutting device.

[0041] The sheet 10 is arranged on one side of the rack, the cutting table is installed on the rack, the cutting table is provided with a cutting plate 20 for supporting the sheet 10, the cutting plate 20 is provided with a cutting groove 21, the laser cutting device is arranged above the cutting table, the laser cutting device corresponds to the cutting groove 21, and the laser cutting device is used for cutting the sheet 10, so that the sheet 10 is cut into the pole piece 70.

[0042] Specifically, the sheet 10 is the material for manufacturing single pole piece 70, and is moved on the rack in the form of unwinding the roll material, and a roller feeding mechanism is arranged on the rack and used for feeding the roll-shaped sheet 10 to the cutting table along the length direction of the rack. The continuous unwinding of the roll material can realize continuous production, reduce the frequency of material replacement, reduce manual intervention, improve the production automation level and production efficiency, and can realize continuous cutting, and the material utilization rate is higher.

[0043] The cutting table is installed on the rack, the cutting plate 20 on the cutting table is used for placing the sheet 10, the cutting plate 20 is further provided with the cutting groove 21, the shape of the cutting groove 21 is the shape of the pole piece 70 to be manufactured, the cutting groove 21 is a through structure, and the laser cutting device is arranged above the cutting plate 20, and the laser cutting device can cut the sheet 10 along the shape of the cutting groove 21.

[0044] During the laser cutting process, the laser beam is concentrated on the surface of the sheet 10, generating high temperature to melt or vaporize the sheet 10, and the cutting groove 21 helps to control the heat diffusion, reduce the heat affected zone, and also release the thermal stress of laser cutting, reducing the risk of deformation of the pole piece 70. Because the laser cutting follows the path of the cutting groove 21, the cutting path can be accurately controlled to avoid overcutting or undercutting, ensuring the dimensional accuracy of the cut piece. The cutting groove 21 can also control the molten slag and spatter generated during laser cutting, reduce the attachment of burrs and spatter, and improve the smoothness and quality of the cutting surface, thereby improving the cutting quality and precision.

[0045] In this way, the pole piece 70 is formed by cutting using a laser cutting device, and the cutting precision of laser cutting is higher, which can cut complex geometric shapes and small features with low error. Moreover, the laser cutting incision is smoother and has fewer burrs, and laser cutting does not require the use of physical tools, eliminating tool wear and replacement costs. Laser cutting is more cost-effective than conventional hardware cutting under long-term use conditions. Using laser cutting instead of hardware cutting reduces manufacturing costs and improves product competitiveness.

[0046] In this embodiment, the pole piece 70 is formed by cutting the sheet 10 along the cutting groove 21. The sheet 10 is fed to the cutting table by the driving roller of the roller feeding mechanism, and the position of the sheet 10 on the cutting table can be flush with one side of the cutting groove 21. In this way, when laser cutting is performed, one side of the sheet 10 does not need to be cut, and the other three sides can be cut. After cutting the other three sides, the pole piece 70 formed is the same size as the required pole piece 70. In this embodiment, the sheet 10 needs to be processed once with high precision before being fed to the cutting table along the length direction of the rack. The width of the sheet 10 needs to be controlled to the required size of the height of the pole piece 70. In this embodiment, the sheet 10 is fed to the cutting table along the length direction of the rack, and one side of the pole piece 70 is flush with one side of the sheet 10 in the width direction of the rack.

[0047] Alternatively, both sides of the sheet 10 can exceed the cutting groove 21, so that the four edges of the sheet 10 need to be cut. However, the sheet 10 does not need to be processed in advance, and the precision requirement of the sheet 10 is low, and the conventional slitting sheet 10 can meet the production requirements.

[0048] Any of the above methods of cutting the pole piece 70 can achieve single-station one-time cutting and forming of the pole piece 70. The formed pole piece 70 has higher precision, and the efficiency of producing the pole piece 70 is improved, and fewer devices are used, saving device space.

[0049] Therefore, the pole piece 70 is cut and formed by the laser cutting device in a single station at one time, the formed pole piece 70 has higher precision, the production efficiency of the pole piece 70 is improved, no physical cutter is needed, there is no cutter wear and replacement cost, the cost is lower under long-term use condition, the manufacturing cost is reduced, the competitiveness of the product is improved, and less equipment is used, and the equipment occupation space is saved.

[0050] When the size of the pole piece 70 is small, a single laser cutting device can meet the production efficiency requirement, and a large-power laser cutting device can be directly carried to complete the entire pole piece work. When the size of the pole piece 70 is large, a plurality of laser cutting devices are needed to splice to complete the cutting of the full-size pole piece 70, but the high forming precision of the pole piece 70 can still be realized. Therefore, the laser cutting device is at least one, and can be two or more.

[0051] Referring to Figure 2 As shown in the figure, the pole piece cutting device further comprises a first dust removal device, the first dust removal device comprises a dust removal cover 30, the dust removal cover 30 is arranged on the upper side of the cutting plate 20 and at least partially surrounds the cutting groove 21 on the cutting plate 20, and the side of the dust removal cover 30 facing the cutting plate 20 is provided with a suction port 31. The first dust removal device is used for removing dust generated in the laser cutting process to avoid the influence of the dust on the yield of the battery 60 and the performance of the subsequent battery 60. Specifically, the dust removal cover 30 is approximately in the shape of a "C" when viewed from above, is located directly above the cutting plate 20, and is partially arranged around the cutting groove 21. The dust removal cover 30 is provided with a suction port 31, the suction port 31 is in communication with a pipeline, and the dust generated in the laser cutting process can be sucked into the suction port 31 and discharged through the pipeline.

[0052] Referring to Figure 2 As shown in the figure, the pole piece cutting device further comprises a blowing device 40, the blowing device 40 comprises a air knife 41 and a blowing pipeline 42, the air knife 41 is arranged on the upper side of the sheet 10 and is in communication with the blowing pipeline 42, the dust removal cover 30 surrounds the blowing device 40, and the dust removal cover 30 is provided with a avoiding space for avoiding the blowing pipeline 42.

[0053] The blowing device 40 is arranged above the cutting plate 20 and the pole piece 70, and an air flow isolation is formed between the cutting path and the pole piece 70 to fully ensure the yield of the pole core production. The air knife 41 is a cover-shaped air knife 41 structure, covers the upper side of the sheet 10, and a tapered passage arranged in the cover-shaped air knife 41 structure can compress the gas, so that the gas pressure is larger when the gas is blown out, the dust can be blown up, and the yield of the battery 60 is avoided. The air knife 41 is in communication with the blowing pipeline 42, the blowing pipeline 42 is connected to the gas for blowing up the dust, and the blowing pipeline 42 needs to be in communication with other devices. The dust removal cover 30 is provided with an avoiding space for avoiding the blowing pipeline 42.

[0054] And, the projection of the air knife 41 on the cutting plate 20 is located in the cutting groove 21. In this way, it can be ensured that the air knife 41 does not affect the path of laser cutting during laser cutting, and the air knife 41 is tightly attached to the inside of the cutting groove 21, which can isolate the pole piece 70 and the dust splashed during cutting. When laser cutting the sheet 10, the air blowing pipe 42 is connected to the gas, and the gas is further compressed by the conical passage in the cover-shaped air knife 41 structure and is sprayed out of the air outlet, wherein the direction of the air outlet is inclined to the inside of the edge of the cutting groove 21, and after the high-speed airflow is sprayed into the inside of the cutting groove 21, the dust generated during cutting is carried into the suction port of the dust removal cover 30, and is concentrated and discharged by the dust removal cover 30, avoiding the dust falling on the surface of the pole piece 70, and improving the yield of the battery 60.

[0055] When using such a dust removal cover 30 and air blowing structure, the laser cutting path needs to avoid the air blowing pipe 42, so at most only the cutting of three edges of the pole piece 70 can be performed, and through the previous processing, one side of the sheet 10 can be flush with one side of the cutting groove 21.

[0056] In some embodiments, the upper side of the pole piece 70 is flush with the upper side of the sheet 10. Referring to the laser cutting path shown in Figure 10 When the air blowing pipe 42 is located on the upper side of the pole piece 70, in order to avoid the cutting path interfering with the air blowing pipe 42, the upper side of the sheet 10 is processed in advance by laser cutting the remaining three edges, and the upper edge of the pole piece 70 after cutting and forming is the upper edge of the sheet 10.

[0057] In some embodiments, the lower side of the pole piece 70 is flush with the lower side of the sheet 10. Referring to the laser cutting path shown in Figure 8 When the air blowing pipe 42 is located on the bottom edge of the pole piece 70, the lower side of the sheet 10 is processed in advance by laser cutting the remaining three edges, and the lower edge of the pole piece 70 after cutting and forming is the lower edge of the sheet 10.

[0058] In some embodiments, the upper side and the lower side of the pole piece 70 are not flush with the upper side and the lower side of the sheet. Referring to the laser cutting path shown in Figure 5As shown, the projection of the dust hood 30 on the cutting plate 20 can also be arranged around the cutting groove 21, that is, a "hui" type dust hood 30 can also be used to absorb and discharge dust, and the dust hood 30 is provided with an air suction port 31 which is in communication with a pipeline, so that the laser cutting dust can be sucked into the air suction port 31 and discharged through the pipeline. Since the dust hood 30 is in a closed shape and completely surrounds the cutting groove 21, the blowing device 40 is not needed, and the dust is only absorbed by the negative pressure of the dust hood 30. In this way, there is no interference between the blowing pipeline 42 and the laser cutting path, and the laser can complete full-size cutting, and both sides of the sheet 10 can exceed the cutting groove 21, and the upper side and the lower side of the sheet and the upper side and the lower side of the sheet are not aligned, so that the sheet 10 has low requirements for incoming material precision, and the conventionally slit sheet 10 can meet the production requirements.

[0059] The pole piece 70 includes: a hollow foil area 71 and a tab area 72, the hollow foil area 71 and the tab area 72 are connected to each other, in some embodiments, the side of the hollow foil area 71 away from the tab area 72 is flush with the lower side of the sheet. Figure 10 As shown in the laser cutting path, the blowing pipeline 42 is located in the tab area 72, and the upper side of the sheet 10 is cut into the remaining three edges by the laser through the previous treatment, and the upper edge of the pole piece 70 after cutting and forming is the upper edge of the sheet 10.

[0060] In some embodiments, the side of the hollow foil area 71 away from the tab area 72 is flush with the upper side of the sheet 10. Referring to Figure 8 As shown in the laser cutting path, the blowing pipeline 42 is located on the side of the hollow foil area 71 away from the tab area 72, and the lower side of the sheet 10 is cut into the remaining three edges by the laser through the previous treatment, and the lower edge of the pole piece 70 after cutting and forming is the lower edge of the sheet 10.

[0061] In some embodiments, the side of the hollow foil area 71 away from the tab area 72 and the tab area 72 are not flush with the upper side and the lower side of the sheet. When the laser cutting equipment uses a "hui" type dust hood 30, both sides of the sheet 10 can exceed the cutting groove 21, and the side of the hollow foil area 71 away from the tab area 72 and the tab area 72 are not flush with the upper side and the lower side of the sheet, so that the sheet 10 has low requirements for incoming material precision, and the conventionally slit sheet 10 can meet the production requirements.

[0062] According to the test results, there are obvious differences between the laser cutting and forming pole piece 70 and the hardware cutting and forming pole piece 70 in the cross section and the front of the pole piece 70, referring to Figure 14 As shown, the hardware cutting cross-sectional image is shown as 01 in the figure, the end face of the pole piece 70 has obvious shear deformation, and the current collector is deformed and discontinuous.

[0063] A typical cross-sectional image of a poor laser cutting state is shown in FIG. 02, and the cross section of the pole piece 70 after high heat from laser cutting appears molten. A cross-sectional image of a good laser cutting state is shown in FIG. 03, and the cross section of the pole piece 70 is regular, the current collector is continuous and clear, but the common point of laser cutting in different states is that the cross section is not stress deformed.

[0064] A heat-affected zone is formed at the edge of the pole piece 70, and the size of the heat-affected zone is h, which satisfies the relationship: 10um≤h≤200um. The size of the heat-affected zone can be used to determine the forming method of the pole piece 70.

[0065] Specifically, the heat-affected zone of laser cutting is small, resulting in material deformation much smaller than the shear deformation caused by hardware cutting. It should be noted that the high heat during laser processing will oxidize the adhesive near the cutting path, i.e., the edge of the pole piece 70, resulting in a color change of the pole piece 70. In theory, the overall shape of the heat-affected zone on the pole piece 70 is Gaussian, so the heat-affected zone is most obvious at the laser incidence surface. In addition, due to the difference in the laser used and the difference in the processing parameters, the size of the heat-affected zone (HAZ) will also differ. Generally, the size of the heat-affected zone is in the range of 10-200um. That is, the size of the heat-affected zone can be used to determine whether the pole piece 70 is formed by laser cutting or hardware cutting. The pole piece 70 formed by laser cutting generally has a heat-affected zone size in the range of 10-200um.

[0066] In some embodiments, the edge of one pole piece 70 overlaps the edge of another pole piece 70. Referring to the laser cutting path shown in FIG. 01, the edges of two adjacent pole pieces 70 do not need to be cut repeatedly, and the production efficiency is higher. Figure 9 and Figure 13 In some embodiments, the edge of one pole piece 70 overlaps the edge of another pole piece 70. Referring to the laser cutting path shown in FIG. 01, the edges of two adjacent pole pieces 70 do not need to be cut repeatedly, and the production efficiency is higher.

[0067] In some embodiments, the edge of one pole piece 70 overlaps the edge of another pole piece 70. Referring to the laser cutting path shown in FIG. 01, the edges of two adjacent pole pieces 70 do not need to be cut repeatedly, and the production efficiency is higher. Figure 12 In some embodiments, the edge of one pole piece 70 overlaps the edge of another pole piece 70. Referring to the laser cutting path shown in FIG. 01, the edges of two adjacent pole pieces 70 do not need to be cut repeatedly, and the production efficiency is higher.

[0068] Further, the pole piece 70 is formed by one-time laser cutting, avoiding the cooperation of the laser cutting device and the hardware cutter, and having better production flexibility, so it can be used to produce special-shaped pole pieces 70. Referring to the laser cutting path shown in FIG. 02, the middle "L" shaped part of the pole piece 70 is obviously not suitable for cutter forming, and the cutting range is located in the middle of the pole piece 70 instead of the top and bottom of the pole piece 70, which cannot be achieved by laser cutting only at the edge. Figure 11

[0069] Figure 3 ​​As shown, the pole piece cutting device further comprises: a suction device, a plurality of suction ports 51 are arranged on the outer periphery and the inner periphery of the cutting groove 21, and the suction device and the plurality of suction ports 51 are communicated for adsorbing the sheet 10. The sheet 10 is arranged above the suction port 51, the suction port 51 is a through structure, and the sheet 10 can be fixed by suction of the suction device, negative pressure below the suction port 51, facilitating laser cutting, and also absorbing dust generated by laser cutting, achieving the purposes of optimizing the cutting section and reducing the short circuit rate of the battery cell.

[0070] Referring to Figure 6 As shown, according to the battery 60 of the second aspect of the utility model, the pole piece is cut by the pole piece cutting device, and the pole piece comprises: a positive pole piece 61, a negative pole piece 62 and a plurality of diaphragms 63, and the plurality of diaphragms 63 are respectively arranged between adjacent positive pole pieces 61 and negative pole pieces 62. Wherein the positive pole piece 61 and the negative pole piece 62 can be made by the pole piece cutting device, and the preparation process of the laminated battery 60 is as follows:

[0071] 1. The roll-shaped sheet 10 is fed to the cutting table along the length direction of the rack by the roller feeding mechanism.

[0072] 2. When the sheet 10 reaches the cutting plate 20 corresponding to the laser cutting device, the roller feeding mechanism stops moving, and the suction port 51 below the cutting plate 20 fixes the pole piece by negative pressure.

[0073] 3. The first dust removal device, the air blowing device 40 and the laser cutting device work, and the pole piece cutting is completed according to the set path (the pole piece is formed after cutting).

[0074] 4. The platform moves or the manipulator moves to take the material, and the formed pole piece is taken.

[0075] 5. The positive / negative pole piece part repeats the above-mentioned 1-3 processes to circulate the pole piece.

[0076] 6. The prepared positive and negative pole pieces of the battery 60 are alternately stacked on the laminated platform, and the laminated pole core is prepared after heat pressing.

[0077] 7. The battery 60 is prepared after assembly, liquid injection, formation and other processes.

[0078] Wherein, if the overall size of the pole piece is small, a single laser cutting device can meet the production requirements, and one laser can be arranged in the cutting area. Generally, for the negative electrode material, the cutting difficulty is low, and the nanosecond laser is preferred, and the laser power is 200W-1000W. When cutting the positive pole piece 61 and other difficult-to-cut materials, the picosecond laser is preferred, and the laser power is 200W-1000W. If the pole piece size is large or the pole piece efficiency is required to be high, two or more lasers can also be selected for cutting path splicing.

[0079] It should also be noted that the pole piece cutting equipment is suitable for pole pieces with a width of 10-500mm, a height of 15-500mm, and a thickness of 20-200um. After splicing and cutting at the same station using two or more lasers, the processing size of the pole piece can be increased to 1000*1000mm.

[0080] And, refer to Figure 7 As shown, on any side in any direction, the protrusion of the separator 63 relative to the negative electrode sheet 62 is L1, where L1 satisfies the relationship: 0.5mm≤L1≤1.3mm. On any side in any direction, the protrusion of the negative electrode sheet 62 relative to the positive electrode sheet 61 is L2, where L2 satisfies the relationship: 0.25mm≤L2≤0.45mm. Specifically, within the battery 60, the separator 63 needs to wrap around the negative electrode, and the negative electrode needs to wrap around the positive electrode. Due to the high precision of laser one-step cutting, especially when using a spaced cutting method, the electrode sheet forming accuracy is very high. This higher electrode sheet manufacturing accuracy provides a prerequisite for reducing the size of the stacked sheets. Due to the high manufacturing accuracy of the battery 60, the dimensional margin of the separator 63 wrapping around the negative electrode (SAOH) and the dimensional margin of the negative electrode wrapping around the positive electrode (ACOH) can be designed to be smaller during the design of the battery 60, i.e., SAOH: 0.9±0.4mm, ACOH: 0.35±0.1mm, resulting in a battery 60 with a higher energy density.

[0081] The pole pieces in the battery 60 are manufactured using pole piece cutting equipment, which simplifies the manufacturing process of the laminated battery 60 to a certain extent and saves space for equipment development.

[0082] The electrical device according to the third embodiment of the present invention includes a battery 60 .

[0083] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the 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, and therefore should not be understood as a limitation to the present invention.

[0084] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily mean the same embodiment or example.

[0085] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made thereto without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A pole piece, characterized in that: The pole piece is made by cutting a sheet material by a laser cutting device, and one side of the pole piece is at most flush with one side of the sheet material.

2. The pole piece according to claim 1, characterized in that: The upper side of the pole piece is flush with the upper side of the sheet; Alternatively, the lower side of the pole piece is flush with the lower side of the sheet; Alternatively, the upper side and the lower side of the pole piece are not flush with the upper side and the lower side of the sheet.

3. The pole piece according to claim 1, characterized in that: The electrode sheet includes: a hollow foil area and a tab area, wherein the hollow foil area and the tab area are connected to each other; wherein, The side of the empty foil area facing away from the tab area is flush with the lower side of the sheet; Alternatively, the side of the empty foil area facing away from the tab area is flush with the upper side of the sheet; Alternatively, the side of the empty foil area facing away from the tab area and the tab area are not flush with the upper side and the lower side of the sheet.

4. The pole piece according to claim 1, characterized in that: A heat-affected zone is formed at the edge of the pole piece, and the size of the heat-affected zone is h, and h satisfies the relationship: 10um≤h≤200um.

5. The pole piece according to claim 1, characterized in that: An edge of one of the pole pieces coincides with an edge of the other pole piece.

6. The pole piece according to claim 1, characterized in that: A sheet material is provided between an edge of one of the pole pieces and an edge of the other pole piece.

7. A battery, characterized in that: include: The electrode sheet according to any one of claims 1 to 6, wherein the electrode sheet comprises: a positive electrode sheet and a negative electrode sheet; A plurality of separators are respectively sandwiched between the adjacent positive electrode sheets and the adjacent negative electrode sheets.

8. The battery according to claim 7, characterized in that On one side in any direction, the protruding dimension of the separator relative to the negative electrode sheet is L1, and L1 satisfies the relationship: 0.5 mm ≤ L1 ≤ 1.3 mm.

9. The battery according to claim 7, characterized in that On one side in any direction, the protruding dimension of the negative electrode sheet relative to the positive electrode sheet is L2, and L2 satisfies the relationship: 0.25mm≤L2≤0.45mm.

10. An electrical device, characterized in that: include: The battery according to any one of claims 7 to 9.

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