Battery cell and manufacturing method thereof, battery device, and electric device

Abstract

The application relates to the technical field of batteries, in particular to a battery monomer, a manufacturing method thereof, a battery device and an electric equipment. In the embodiment of the application, a convex part is arranged on the first circle segment and the last circle segment of the main body part of the first pole piece, and the stiffness of the convex part is greater than that of the first pole lug, so that the bending resistance of the convex part is greater than that of the first pole lug. In the embodiment of the application, when the tension changes, the bending resistance of the convex part is greater than that of the first pole lug, so that the convex part can be in a more stable state compared with the first pole lug when the tension changes, the winding alignment and the winding alignment of the electrode assembly can be determined by using the convex part which is less prone to bending, the detection accuracy of the winding alignment and the winding alignment is improved, and the detection accuracy of the alignment of the electrode assembly is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery monomer, a manufacturing method thereof, a battery device and an electric equipment. BACKGROUND

[0002] At present, the electrode assembly in the battery is mainly manufactured through a lamination process or a winding process. In the manufacturing process of the winding electrode assembly, the alignment degree is a key index for measuring the relative position accuracy of the positive and negative electrode sheets in the winding process, and the advantages and disadvantages thereof directly affect the performance, safety and production consistency of the electrode assembly. Therefore, it is necessary to improve the detection accuracy of the alignment degree of the electrode assembly. SUMMARY

[0003] Based on this, the present application provides a battery monomer, a manufacturing method thereof, a battery device and an electric equipment to improve the detection accuracy of the alignment degree of the electrode assembly.

[0004] According to one aspect of the present application, the present application provides a battery monomer, comprising an electrode assembly, the electrode assembly is in a winding structure, and the electrode assembly comprises a first electrode sheet, a second electrode sheet and a separator, the separator separates the first electrode sheet and the second electrode sheet. The first electrode sheet comprises a main body part, a plurality of first tabs and a protruding part respectively arranged at a first circle segment and a last circle segment of the main body part; along the winding axis direction of the electrode assembly, the plurality of first tabs and all the protruding parts are arranged on the same side of the main body part, and the stiffness of the protruding part is greater than the stiffness of the first tab.

[0005] In the technical scheme of the present application, the protruding part is arranged at the first circle segment and the last circle segment of the main body part of the first electrode sheet, and the stiffness of the protruding part is greater than the stiffness of the first tab, so that the bending resistance of the protruding part is greater than the bending resistance of the first tab. Since there is no tension constraint when the head and tail of the first electrode sheet are cut off, the actual relative position of the first electrode sheet and the second electrode sheet may change during winding, thereby causing the result of the electrode sheet alignment degree detection to be inaccurate. In the present application, since the bending resistance of the protruding part is greater than the bending resistance of the first tab, the protruding part can be in a more stable state relative to the first tab when the tension changes, so that the winding alignment degree and the winding alignment degree of the electrode assembly can be determined by using the protruding part which is less likely to bend, the detection accuracy of the winding alignment degree and the winding alignment degree is improved, and the detection accuracy of the alignment degree of the electrode assembly is further improved.

[0006] In some embodiments, the first electrode sheet further comprises an insulating layer, the insulating layer comprises a first insulating part and a second insulating part connected with the first insulating part; the edge region of the side where the plurality of first tabs and the protruding part are arranged of the main body part is a first region, and the root region of the first tab adjacent to the main body part is a second region; the first insulating part is arranged at the first region, and the second insulating part covers at least part of the protruding part and is arranged at the second region.

[0007] By setting the insulating layer, the insulating protection effect can be achieved. Even if the first tab is inserted between the first and second tabs, the first tab and the second tab can be separated by the insulating layer, thereby reducing the risk of short circuit and improving safety performance. Since the insulating layer has a certain thickness, the thickness of the area of the first tab covered with the insulating layer can be increased, the cross-sectional moment of inertia can be improved, and thus the stiffness of the area of the first tab covered with the insulating layer can be increased, which is conducive to further improving the stiffness of the protrusion, and further improving the detection accuracy of the in-roll alignment and the roll alignment.

[0008] In some embodiments, the protrusion includes a first surface and a second surface oppositely arranged along a thickness direction of the protrusion; the thickness direction of the protrusion is perpendicular to a winding axis direction of the electrode assembly; wherein the ratio of the area of the first surface covered by the second insulating part to the area of the first surface is 0.8 to 1; and / or, the ratio of the area of the second surface covered by the second insulating part to the area of the second surface is 0.8 to 1.

[0009] By controlling the area ratio of the first surface and / or the second surface of the protrusion covered by the second insulating part, the stiffness of the protrusion can be further improved, and the detection accuracy of the in-roll alignment and the roll alignment can be further improved.

[0010] In some embodiments, the ratio of the surface area of the area of the protrusion covered by the second insulating part to the surface area of the protrusion is 0.8 to 1.

[0011] By controlling the area ratio of the protrusion covered by the second insulating part, the stiffness of the protrusion can be further improved, and the detection accuracy of the in-roll alignment and the roll alignment can be further improved.

[0012] In some embodiments, along the winding axis direction of the electrode assembly, the size of the protrusion is smaller than the size of the first tab; and / or, along the winding direction of the electrode assembly, the size of the protrusion is smaller than the size of the first tab.

[0013] By controlling the size of the protrusion along the winding axis direction of the electrode assembly and / or along the winding direction of the electrode assembly, the stiffness of the protrusion can be adjusted.

[0014] In some embodiments, the ratio of the size of the protrusion along the winding direction of the electrode assembly to the size of the protrusion along the winding axis direction of the electrode assembly is greater than or equal to 7.

[0015] By controlling the ratio of the size of the protrusion along the winding direction of the electrode assembly to the size of the protrusion along the winding axis direction of the electrode assembly, the stiffness of the protrusion can be further adjusted.

[0016] In some embodiments, the electrode assembly has a reference plane on which the winding axis of the electrode assembly is located; the reference plane has oppositely arranged first and second sides, the plurality of first tabs are located on the first side, and all the protrusions are located on the second side.

[0017] By arranging the first tabs and the protrusions on different sides, all the first tabs can be arranged in the same region, which not only facilitates the connection of all the first tabs with the electrode terminals of the battery monomer, but also helps to improve the space utilization.

[0018] In some embodiments, the orthogonal projection of all the protrusions on the reference plane has an overlapping portion with the orthogonal projection of the plurality of first tabs on the reference plane.

[0019] In this way, the protrusions can provide a supporting force to support the first tabs, thereby reducing the risk of short circuit caused by the insertion of the first tabs between the first and second tabs during the process of installing the electrode assembly into the shell of the battery monomer after the connection of the first tabs with the electrode terminals of the battery monomer, so as to reduce the risk of tab redundancy and improve safety performance.

[0020] In some embodiments, the orthogonal projection of any one of the protrusions on the reference plane has an overlapping portion with the orthogonal projection of any one of the first tabs on the reference plane; and / or, the number of the loop segments of the main body part is M, and the number of the loop segments provided with the protrusions is N; wherein 0.5≤N / M≤1, and N and M are positive integers.

[0021] In this way, each protrusion can provide a supporting force acting on the first tabs, thereby further improving the supporting effect on the first tabs and further reducing the risk of tab redundancy. By controlling the number of loop segments provided with the protrusions, the protrusions can have a certain supporting effect on the first tabs.

[0022] In some embodiments, at least one intermediate loop segment of the main body part is provided, and the at least one intermediate loop segment is provided with the protrusions.

[0023] In this way, since the at least one intermediate loop segment is provided with the protrusions, the alignment of the intermediate loop segment can be verified by the protrusions provided on the intermediate loop segment, thereby facilitating the further improvement of the detection accuracy of the alignment of the electrode assembly. When the orthogonal projection of the protrusions on the reference plane has an overlapping portion with the orthogonal projection of the first tabs on the reference plane, the supporting performance of the protrusions on the first tabs can be improved.

[0024] In some embodiments, the intermediate loop segment is provided in multiple loops, and each intermediate loop segment is provided with the protrusions.

[0025] In this way, the convex portion of each intermediate ring segment can be used to check the alignment of the intermediate ring segment, thereby further facilitating the detection accuracy of the alignment of the electrode assembly. When the convex portion on each intermediate ring segment has an overlapping portion with the normal projection of the first tab on the reference surface, the support performance of the convex portion on the first tab is further improved.

[0026] In some embodiments, along the winding direction of the electrode assembly, the same number of first tabs is arranged between every two adjacent convex portions.

[0027] Since the distribution of the convex portions and the first tabs has periodicity, not only can the tension for winding the electrode assembly be more balanced along the circumferential direction of the winding, thereby improving the stability of the winding formation, but also facilitates the automatic production of the first tabs and the convex portions.

[0028] In some embodiments, the convex portion has a first projection on a plane perpendicular to the thickness direction of the convex portion, and the thickness direction of the convex portion is perpendicular to the winding axis direction of the electrode assembly; the shape of all the first projections comprises at least one of a rectangle, a square, a rhombus, and a trapezoid.

[0029] In this way, by controlling the shape of the convex portion, the manufacturing convenience is improved while the convex portion has certain mechanical properties.

[0030] In some embodiments, along the winding direction of the electrode assembly, the size of the convex portion along the winding axis direction of the electrode assembly changes in a first rule; the first rule comprises one of unchanging, first decreasing and then increasing, first increasing and then decreasing, first decreasing and then increasing and then decreasing, and first increasing and then decreasing and then increasing.

[0031] When the first rule is unchanging, it is beneficial to make the convex portion have certain mechanical properties while facilitating the production of the convex portion. When the first rule comprises one of first decreasing and then increasing, first increasing and then decreasing, first decreasing and then increasing and then decreasing, and first increasing and then decreasing and then increasing, it is beneficial to control the mechanical stress through the morphological change of the convex portion, thereby improving the reliability of the convex portion.

[0032] In some embodiments, along the winding axis direction of the electrode assembly, the size of the convex portion along the winding direction of the electrode assembly changes in a second rule; the second rule comprises one of unchanging, decreasing, increasing, first decreasing and then increasing, first increasing and then decreasing, first decreasing and then increasing and then decreasing, and first increasing and then decreasing and then increasing.

[0033] When the second rule is unchanging, it is beneficial to make the convex portion have certain mechanical properties while facilitating the production of the convex portion. When the second rule comprises one of decreasing, increasing, first decreasing and then increasing, first increasing and then decreasing, first decreasing and then increasing and then decreasing, and first increasing and then decreasing and then increasing, it is beneficial to control the mechanical stress through the morphological change of the convex portion, thereby improving the reliability of the convex portion.

[0034] In some embodiments, the protrusion has a dimension along the winding axis direction of the electrode assembly of 2mm to 6mm; and / or, a dimension along the winding direction of the electrode assembly of 5mm to 9mm.

[0035] By controlling the height and / or width of the protrusion, not only is the protrusion easy to manufacture, but also the protrusion has certain mechanical reliability and is adapted to the space limitations during winding.

[0036] In some embodiments, the first tab is a positive electrode tab, and the second tab is a negative electrode tab.

[0037] In this way, the positive electrode tab includes the first tab and the protrusion. Since the overall rigidity of the positive electrode tab is greater than that of the negative electrode tab, the stability of the protrusion is improved, and the detection accuracy of the alignment is improved. At the same time, since the size of the negative electrode tab is usually slightly larger than that of the positive electrode tab, using the protrusion on the positive electrode tab as a detection reference, it is more direct to judge whether the negative electrode tab effectively covers the positive electrode tab.

[0038] According to another aspect of the present application, the present application provides a method for manufacturing a battery cell, comprising:

[0039] providing a first tab, a second tab, and a separator; the first tab includes a main body, a plurality of first tabs, and a protrusion respectively arranged at the first and last winding sections of the main body; along the width direction of the first tab, the plurality of first tabs and all the protrusions are arranged on the same side of the main body, and the stiffness of the protrusion is greater than the stiffness of the first tab;

[0040] stacking and winding the separator, the first tab, and the second tab to form an electrode assembly;

[0041] In the case where the in-winding alignment and the winding alignment of the first tab and the second tab both meet the alignment qualification condition, the electrode assembly is loaded into the receiving cavity of the shell to form a battery cell; wherein the in-winding alignment is determined based on the protrusion located at the first winding section of the main body, and the winding alignment is determined based on the protrusion located at the last winding section of the main body.

[0042] In the technical solution of the embodiment of the application, the convex part is arranged on the first circle segment and the last circle segment of the main body part of the first tab, and the stiffness of the convex part is greater than the stiffness of the first tab, so that the bending resistance of the convex part is greater than the bending resistance of the first tab. Since the head part and the tail part of the first tab are not bound by tension when being cut off, the actual relative position of the first tab and the second tab may change during winding, so that the result of the alignment detection of the tab is inaccurate. In the embodiment of the application, since the bending resistance of the convex part is greater than the bending resistance of the first tab, when the tension changes, the convex part can be in a more stable state relative to the first tab, so that the winding alignment and the winding alignment of the electrode assembly can be determined by using the convex part which is less likely to be bent, the detection accuracy of the winding alignment and the winding alignment is improved, and the detection accuracy of the alignment of the electrode assembly is further improved.

[0043] In some embodiments, the method for manufacturing the battery cell further includes:

[0044] The first image of the convex part located on the first circle segment of the main body part and the main body part before the first tab is wound is acquired; and the first distance between the convex part located on the first circle segment of the main body part and the main body part in the width direction of the first tab is determined according to the first image.

[0045] The second image of the convex part located on the first circle segment of the main body part and the main body part wound on the winding part after the first tab is wound is acquired; and the second distance between the convex part located on the first circle segment of the main body part and the second tab in the width direction of the first tab is determined according to the second image.

[0046] Whether the winding alignment meets the alignment qualified condition is determined based on the difference between the first distance and the second distance.

[0047] During the winding process of the first tab, the tension of the first tab changes. Since the convex part located on the first circle segment of the main body part can be in a more stable state, the first distance between the convex part located on the first circle segment of the main body part and the main body part determined is more accurate, which is beneficial to improve the accuracy of the detected winding alignment.

[0048] In some embodiments, the method for manufacturing the battery cell further includes:

[0049] The third image of the convex part located on the last circle segment of the main body part and the main body part before the last circle segment of the main body part is wound is acquired; and the third distance between the convex part located on the last circle segment of the main body part and the main body part in the width direction of the first tab is determined according to the third image.

[0050] The fourth image is obtained after the last winding section of the main body is wound, and the convex portion located at the last winding section of the main body and the main body are wound on the winding piece; and the fourth distance between the convex portion located at the first winding section of the main body and the second pole piece in the width direction of the first pole piece is determined according to the fourth image.

[0051] The difference between the third distance and the fourth distance is used to determine whether the winding alignment meets the alignment qualified condition.

[0052] During the winding of the first pole piece, the tension of the first pole piece changes. Since the convex portion located at the last winding section of the main body can be in a more stable state, the third distance between the convex portion located at the last winding section of the main body and the main body determined is more accurate, which is beneficial to improve the accuracy of the detected winding alignment.

[0053] In some embodiments, the intermediate winding section of the main body is provided with a convex portion; and the method for manufacturing the battery cell further comprises:

[0054] The reference alignment of the intermediate winding sections of the first pole piece and the second pole piece is verified based on the verification alignment of the intermediate winding sections of the first pole piece and the second pole piece; wherein the reference alignment is determined based on the first tab located at the intermediate winding section of the main body, and the verification alignment is determined based on the convex portion located at the intermediate winding section of the main body.

[0055] In the case that the winding-in alignment and the winding alignment both meet the alignment qualified condition, and the reference alignment meets the verification qualified condition, the electrode assembly is loaded into the accommodating cavity of the shell to form the battery cell.

[0056] In this way, the verification alignment is obtained through the convex portion provided on the intermediate winding section, which can further improve the accuracy of the alignment of the intermediate winding section.

[0057] In some embodiments, the first pole piece, the second pole piece and the separator are provided, comprising:

[0058] The first pole piece strip is provided;

[0059] The first pole piece strip is die-cut to form a plurality of first tabs and all convex portions, so as to obtain the first pole piece.

[0060] In this way, the first tab and the convex portion can be manufactured through the same process, which not only utilizes the structure of the first pole piece to manufacture the convex portion, thereby improving the convenience of manufacturing the convex portion, but also is beneficial to improve the production efficiency.

[0061] In some embodiments, the method for manufacturing the battery cell further comprises:

[0062] When the first pole piece is wound at the winding-in end of the first pole piece, an acting force acting on the side of the winding-in end of the first pole piece away from the winding piece is provided, so that the winding-in end of the first pole piece can be close to the winding piece.

[0063] Thus, by providing the acting force acting on the material inlet end of the first tab, the material inlet end of the first tab can be more stably and reliably fed, and the risk of the material inlet end of the first tab being wrinkled, bent, or the like is reduced, thereby facilitating improvement of the performance of the electrode assembly.

[0064] According to yet another aspect of the present application, the present application provides a battery device comprising the battery cell in any of the above embodiments; or a battery cell manufactured by the manufacturing method of the battery cell in any of the above embodiments.

[0065] The battery device also has the advantages of the battery cell in any of the above embodiments and the battery cell manufactured by the manufacturing method of the battery cell in any of the above embodiments, which will not be repeated here.

[0066] According to still another aspect of the present application, the present application provides a power utilization device comprising the battery device in any of the above embodiments.

[0067] The power utilization device also has the advantages of the battery device in any of the above embodiments, which will not be repeated here.

[0068] The above description is only a summary of the technical solutions of the present application. In order to enable one of ordinary skill in the art to better understand the technical means of the present application and implement it according to the content of the description, and in order to enable the above and other purposes, characteristics and advantages of the present application to be more apparent and understandable, the specific implementation manner of the present application is described below. BRIEF DESCRIPTION OF DRAWINGS

[0069] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the implementation. The accompanying drawings are included only to illustrate implementations and are not considered a limitation of the present application. Moreover, in all the drawings, the same reference numbers are used to denote the same components. In the drawings:

[0070] Figure 1 is a structural schematic diagram of a vehicle in some embodiments of the present application;

[0071] Figure 2 is an exploded structural schematic diagram of a battery device in some embodiments of the present application;

[0072] Figure 3 is an exploded structural schematic diagram of a battery cell in some embodiments of the present application;

[0073] Figure 4 is a perspective structural schematic diagram of an electrode assembly in some embodiments of the present application;

[0074] Figure 5A top view schematic diagram of an electrode assembly in some embodiments of the present application in a schematic case;

[0075] Figure 6 A schematic diagram of a first electrode sheet in an unfolded state in some embodiments of the present application;

[0076] Figure 7 A top view schematic diagram of an electrode assembly in some embodiments of the present application in another schematic case;

[0077] Figure 8 A schematic diagram of a comparative first electrode sheet in an unfolded state in some comparative examples of the present application;

[0078] Figure 9 A top view schematic diagram of a comparative electrode assembly in some comparative examples of the present application;

[0079] Figure 10 A schematic diagram of a comparative electrode assembly in some comparative examples of the present application in a state during fabrication;

[0080] Figure 11 A schematic diagram of a comparative electrode assembly in some comparative examples of the present application in another state during fabrication;

[0081] Figure 12 A schematic diagram of a first electrode sheet in an unfolded state in some embodiments of the present application in a perspective view;

[0082] Figure 13 A schematic diagram of a first electrode sheet in an unfolded state in some embodiments of the present application in another perspective view;

[0083] Figure 14 A sectional view schematic diagram of a partial structure of a battery cell in some embodiments of the present application;

[0084] Figure 15 A schematic diagram of a partial structure of a battery cell in some embodiments of the present application;

[0085] Figure 16 A sectional view schematic diagram of a partial structure of a comparative battery cell in some comparative examples of the present application;

[0086] Figure 17 A schematic diagram of a partial structure of a battery cell in some comparative examples of the present application;

[0087] Figure 18 A flowchart of a fabrication method of a battery cell in some embodiments of the present application;

[0088] Figure 19A schematic view of an electrode assembly in a state during manufacturing in some embodiments of the present application;

[0089] Figure 20 A schematic view of an electrode assembly in another state during manufacturing in some embodiments of the present application;

[0090] Figure 21 A schematic view of steps SI, SJ, SK in a manufacturing method of a battery cell in some embodiments of the present application;

[0091] Figure 22 A schematic view of a first image in some embodiments of the present application;

[0092] Figure 23 A schematic view of a portion of a first electrode sheet corresponding to the first image in some embodiments of the present application;

[0093] Figure 24 A schematic view of a second image in some embodiments of the present application;

[0094] Figure 25 A schematic view of a portion of a wound electrode assembly corresponding to the second image in some embodiments of the present application;

[0095] Figure 26 A schematic view of steps SF, SG, SH in a manufacturing method of a battery cell in some embodiments of the present application;

[0096] Figure 27 A schematic view of a portion of a first electrode sheet corresponding to the third image in some embodiments of the present application;

[0097] Figure 28 A schematic view of a portion of a wound electrode assembly corresponding to the fourth image in some embodiments of the present application;

[0098] Figure 29 A schematic view of steps SO, SP in a manufacturing method of a battery cell in some embodiments of the present application;

[0099] Figure 30 A schematic view of steps S111, S112 in some embodiments of the present application.

[0100] BRIEF DESCRIPTION OF THE DRAWINGS

[0101] Vehicle 1;

[0102] Battery device 10, controller 20, motor 30;

[0103] Battery cell 100, shell 110, housing 111, end cover 112, electrode terminal 1121, electrode assembly 120, first pole piece 121, main body 1211, first coil segment Q1, last coil segment Q2, middle coil segment Q3, first tab 1212, convex part 1213, first face m1, second face m2, first insulating layer 1214, first insulating part 12141, second insulating part 12142, first region Z1, second region Z2, second pole piece 122, second tab 1221, spacer 123;

[0104] Box 200, first box part 210, second box part 220;

[0105] Winding 1000, image acquisition device 2000, first image acquisition component 2100, second image acquisition component 2200, cutting device 3000, conveying device 4000, image acquisition blind area W;

[0106] Contrast electrode assembly 120', contrast first pole piece 121', redundancy area A;

[0107] First distance h1, second distance h2, third distance h3, fourth distance h4;

[0108] First size d1, second size d2, third size d3, fourth size d4;

[0109] Reference surface E;

[0110] First direction F1, second direction F2, third direction F3, winding axis direction J1, winding direction J2, winding axis L. DETAILED DESCRIPTION

[0111] The embodiments of the technical scheme of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical scheme of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0112] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0113] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly specified and limited.

[0114] Reference herein to "embodiments" means that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily a separate or alternative embodiment to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0115] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, B1 and / or B2, which can mean that B1 exists alone, B1 and B2 exist together, and B2 exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after it.

[0116] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0117] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0118] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0119] At present, from the development of market situation, the application of power battery is more and more extensive. The power battery is not only applied to the energy storage power supply system of water power, fire power, wind power and solar power station, but also widely used in electric bicycles, electric motorcycles, electric vehicles and other electric vehicles, military equipment and aerospace and other fields. With the continuous expansion of the application field of power battery, the demand of its market is also increasing.

[0120] In the winding process of the electrode assembly, the alignment of the electrode sheet needs to be detected. The relative position of the positive and negative electrode sheets is usually obtained before winding to detect the alignment, however, due to the absence of tension constraint when the head and tail of the electrode sheet are cut off, the actual relative position of the positive and negative electrode sheets may change during winding, thereby leading to inaccurate alignment detection results.

[0121] Therefore, in order to improve the detection accuracy of the alignment of the electrode assembly, the battery monomer provided by the embodiments of the present application sets protrusions on the first circle segment and the last circle segment of the main body of the first electrode sheet, and uses the protrusions to improve the detection accuracy of the alignment. Specifically, by configuring the stiffness of the protrusions on the first circle segment and the last circle segment of the main body to be greater than the stiffness of the first tab, the bending resistance of the protrusions can be improved, and the alignment can be detected by using the protrusions as a detection reference, thereby improving the detection accuracy of the alignment.

[0122] The battery monomer disclosed in the embodiments of the present application can be used in, but not limited to, electric equipment such as vehicles, ships or aircraft. The power supply system of the electric equipment can be composed of the battery monomer disclosed in the present application and other components. In this way, the detection accuracy of the alignment of the electrode assembly can be improved, thereby improving the performance, safety and production consistency of the battery monomer.

[0123] The embodiments of the present application provide a power consumption equipment using a battery device as a power supply. The power consumption equipment is a device that uses electric energy as energy and realizes corresponding functions by consuming electric energy. Exemplarily, the power consumption equipment can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric car, an electric vehicle, a ship, a spacecraft, etc. The electric toy can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric plane toys, etc. The spacecraft can include airplanes, rockets, space shuttles and spacecraft, etc.

[0124] The power consuming device in the embodiments of the present application can include a device body and a power supply device, the power supply device is used to supply power to the device body, and the power supply device can include a battery cell or a battery pack. The device body refers to the main structure that consumes power to realize corresponding functions. For example, the power consuming device can be a mobile phone, and the device body is the part that can realize communication functions, and the part that can realize communication functions is powered by the battery cell or the battery pack. For example, the power consuming device can be a car, and the device body is the part that can provide a seat for a person and can drive on the road, and the part that can provide a seat for a person and can drive on the road is powered by the battery cell or the battery pack. The power supply device refers to a device that can output power. For example, the battery pack composed of the battery cell can output power.

[0125] The following embodiments are described by taking a power consuming device in an embodiment of the present application as a vehicle for example for convenience of description.

[0126] Please refer to Figure 1 , Figure 1 is a schematic structural diagram of a vehicle 1 in some embodiments of the present application. The vehicle 1 can be a fuel car, a gas car or a new energy car, and the new energy car can be a pure electric car, a hybrid car or a range extended car. The vehicle 1 is internally provided with a battery device 10, which can be arranged at the bottom, the head or the tail of the vehicle 1. The battery device 10 can be used for power supply of the vehicle 1, for example, the battery device 10 can be used as an operating power source of the vehicle 1. The vehicle 1 can further include a controller 20 and a motor 30, and the controller 20 is used to control the battery device 10 to supply power to the motor 30, for example, to meet the power demand of the vehicle 1 during starting, navigation and driving.

[0127] In some embodiments of the present application, the battery device 10 can not only be used as an operating power source of the vehicle 1, but also be used as a driving power source of the vehicle 1, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1.

[0128] In order to meet different power consumption requirements, the battery device 10 can include a plurality of battery cells 100, and the battery cell 100 refers to the smallest unit of a battery module or a battery pack. The plurality of battery cells 100 can be connected in series and / or in parallel via electrode terminals to be applied to various application occasions. The battery mentioned in the present application includes a battery module or a battery pack. Among them, the plurality of battery cells 100 can be connected in series or in parallel or in a mixed manner. The mixed connection refers to a mixture of series connection and parallel connection. The battery device 10 can also be referred to as a battery pack. In the embodiments of the present application, the plurality of battery cells 100 can directly constitute a battery pack, or first constitute a battery module, and then the battery module constitutes a battery pack.

[0129] Please refer to Figure 2 , Figure 2A schematic diagram of an exploded structure of a battery device 10 in some embodiments of the present application. Figure 2 In some embodiments, the battery device 10 can include a plurality of battery modules and a box 200, and the plurality of battery modules are accommodated inside the box 200. The box 200 is used to accommodate the battery monomer 100 to reduce the risk of liquid or other foreign matters affecting the charging or discharging of the battery monomer 100. The box 200 can be a simple cuboid or a cylinder or a sphere or the like, or a complex cuboid structure composed of a simple cuboid or a cylinder or a sphere or the like, and the embodiments of the present application are not limited thereto. The material of the box 200 can be an alloy material such as an aluminum alloy or an iron alloy, a polymer material such as polycarbonate or polyisocyanurate foam plastic, or a composite material such as glass fiber and epoxy resin, and the embodiments of the present application are not limited thereto.

[0130] In some embodiments, the box 200 can include a first box part 210 and a second box part 220, and the first box part 210 and the second box part 220 are mutually covered. The first box part 210 and the second box part 220 jointly define a space for accommodating the battery monomer 100. The second box part 220 can be a hollow structure with one end open, and the first box part 210 can be a plate-shaped structure, and the first box part 210 is covered on the open side of the second box part 220 to jointly define the space for accommodating the battery monomer 100 with the second box part 220. The first box part 210 and the second box part 220 can also be hollow structures with one side open, and the open side of the first box part 210 is covered on the open side of the second box part 220.

[0131] The battery module can include a plurality of battery monomers 100, and the plurality of battery monomers 100 can be connected in series or in parallel or in a mixed manner to form a battery module, and a plurality of battery modules are connected in series or in parallel or in a mixed manner to form a battery. In the present application, the battery monomer 100 can include a lithium ion battery, a sodium ion battery or a magnesium ion battery device, and the embodiments of the present application are not limited thereto. The battery monomer 100 can be in the shape of a cylinder, a flat body, a cuboid or other shapes, and the embodiments of the present application are not limited thereto. The battery monomer 100 can be in the shape of a cylinder, a flat body, a cuboid or other shapes, and the embodiments of the present application are not limited thereto. However, for the sake of simplicity, the following embodiments will be described by taking a square battery monomer as an example.

[0132] Please refer to Figure 3 , Figure 3 A schematic diagram of an exploded structure of a battery monomer 100 in some embodiments of the present application. The battery monomer 100 refers to the smallest unit that constitutes the battery device 10. As shown in Figure 3 , the battery monomer 100 includes a shell 110, an electrode assembly 120 and other functional components.

[0133] The shell 110 is a component for forming an internal environment of the battery cell 100. The shell 110 can include a casing 111 and an end cover 112. The casing 111 is a component for cooperating with the end cover 112 to form the internal environment of the battery cell 100. The internal environment formed thereby can be used to accommodate the electrode assembly 120, electrolyte (not shown in the figure), and other components. The casing 111 and the end cover 112 can be independent components, and an opening can be provided on the casing 111, and the end cover 112 is made to cover the opening to form the internal environment of the battery cell 100. Without limitation, the end cover 112 and the casing 111 can also be integrated, specifically, the end cover 112 and the casing 111 can be formed into a common connecting surface before other components are put into the casing, and when it is necessary to seal the inside of the casing 111, the end cover 112 is made to cover the casing 111. The casing 111 can be of various shapes and sizes, such as a cuboid, a cylinder, a hexagonal prism, etc. Specifically, the shape of the casing 111 can be determined according to the specific shape and size of the electrode assembly 120. The material of the casing 111 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not make special limitations thereon. The opening of the casing 111 can be located on the side or bottom of the casing 111, and the embodiments of the present application do not make limitations thereon.

[0134] The end cover 112 refers to a component that can be fitted on the opening of the housing 111 to isolate the internal environment of the battery cell 100 from the external environment. Without limitation, the shape of the end cover 112 can be adapted to the shape of the housing 111 to fit the housing 111. For example, the end cover 112 can be made of a material with certain hardness and strength, such as aluminum alloy, so that the end cover 112 is less likely to deform when subjected to extrusion collision, allowing the battery cell 100 to have higher structural strength and improved safety performance. The end cover 112 can be provided with functional components such as electrode terminals 1121. The electrode terminals 1121 can be used to electrically connect with the electrode assembly 120 for outputting or inputting the electrical energy of the battery cell 100. In some embodiments, the end cover 112 can also be provided with a pressure relief mechanism for relieving the internal pressure of the battery cell 100 when the internal pressure or temperature of the battery cell 100 reaches a threshold value. In some embodiments, the end cover 112 can also be provided with a liquid injection hole for injecting electrolyte into the interior of the battery cell 100. Of course, the electrode terminals 1121 and the liquid injection hole can also be provided on the housing 111. The material of the end cover 112 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not make special limitations thereon. In some embodiments, an insulating member can also be provided on the inner side of the end cover 112, which can be used to isolate the electrical connection components in the housing 111 from the end cover 112 to reduce the risk of short circuit. For example, the material of the insulating member can be plastic, rubber, etc. In some embodiments, the housing 111 and / or the end cover 112 can also be provided with a pressure relief mechanism. The pressure relief mechanism is used to relieve the internal pressure of the battery cell 100 when the internal pressure or temperature of the battery cell 100 reaches a threshold value, to improve the safety performance of the battery cell 100. The threshold value varies according to different design requirements. The threshold value can depend on the material of one or more of the electrode assembly 120 and the separator in the battery cell 100. The pressure relief mechanism can take the form of a relief valve, a gas valve, a pressure relief valve, or a safety valve, and can specifically take the form of a pressure-sensitive or temperature-sensitive element or structure, i.e., when the internal pressure or temperature of the battery cell 100 reaches the threshold value, the pressure relief mechanism performs an action or the weak structure provided in the pressure relief mechanism is broken, thereby forming an opening or passage for the internal pressure or temperature to be relieved.

[0135] The electrode assembly 120 is a component in which electrochemical reactions occur in the battery cell 100. The housing 110 can contain one or more electrode assemblies 120.

[0136] The electrode assembly 120 is mainly formed by winding the positive electrode sheet and the negative electrode sheet, and generally has a separator between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have portions with active materials, which constitute the main body of the electrode assembly 120, and portions without active materials, which each constitute a tab. The positive electrode tab and the negative electrode tab can be located at one end of the main body or at two ends of the main body respectively, and can be located at the top of the main body or at the side wall of the main body, which are not specifically limited herein. During the charging and discharging process of the battery device 10, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab is connected to the electrode terminal 1121 to form a current loop. The separator is used to separate the positive electrode sheet and the negative electrode sheet, and to prevent the electrons in the battery monomer 100 from freely passing through, so that the ions in the electrolyte can freely flow between the positive electrode sheet and the negative electrode sheet. The separator can be a thin film made of PE (polyethylene), PP (polypropylene) or the like.

[0137] According to some embodiments of the present application, please refer to Figures 4 to 6 , Figure 4 is a perspective view of the electrode assembly 120 in some embodiments of the present application, Figure 5 is a top view of the electrode assembly 120 in some embodiments of the present application, Figure 6 is a structure schematic view of the first electrode sheet 121 in an unfolded state, the present application provides a battery monomer 100, which comprises an electrode assembly 120, the electrode assembly 120 is in a wound structure, the electrode assembly 120 comprises a first electrode sheet 121, a second electrode sheet 122 and a separator 123, the separator 123 separates the first electrode sheet 121 and the second electrode sheet 122. The first electrode sheet 121 comprises a main body 1211, a plurality of first tabs 1212, and a protruding part 1213 arranged at the first coil segment Q1 and the last coil segment Q2 of the main body 1211 respectively. Along the winding axis direction J1 of the electrode assembly 120, the plurality of first tabs 1212 and all the protruding parts 1213 are arranged on the same side of the main body 1211, and the stiffness of the protruding part 1213 is greater than that of the first tab 1212.

[0138] The first electrode sheet 121 and the second electrode sheet 122 are electrode sheets with opposite polarities. One of the first electrode sheet 121 and the second electrode sheet 122 is a positive electrode sheet, and the other is a negative electrode sheet. In the embodiments of the present application, the first electrode sheet 121 can be a positive electrode sheet, and the second electrode sheet 122 can be a negative electrode sheet. The positive electrode sheet, the negative electrode sheet, the separator 123 and the main body 1211 can be understood with reference to the above-mentioned embodiments, which will not be repeated here.

[0139] For example, Figure 4In the illustrated configuration, the first electrode 121 includes a first tab 1212, and the second electrode 122 includes a second tab 1221. The first tab 1212 and the second tab 1221 are located on the same side of the electrode assembly 120. The first tab 1212 and the second tab 1221 are respectively connected to different electrode terminals 1121 of the battery cell 100. The first direction F1, the second direction F2, and the third direction F3 can be considered as the length, width, and height directions of the electrode assembly 120; that is, the first direction F1, the second direction F2, and the third direction F3 can be perpendicular to each other. It should be noted that the length, width, and height directions do not limit the size of the electrode assembly 120, but rather indicate that the electrode assembly 120 has certain dimensions in three directions. The winding axis direction J1 of the electrode assembly 120 is the extension direction of the winding axis L of the electrode assembly 120, and the extension direction of the winding axis L of the electrode assembly 120 can be the first direction F1. That is, the first tab 1212 and the protrusion 1213 are provided on one side of the main body 1211 along the first direction F1.

[0140] In the structure of the wound electrode assembly 120, a "segment" is a structural unit defined based on the sequence and positional characteristics of the winding process of the electrode sheet and the separator 123, used to describe the winding portion at different positions. The number of segments is consistent with the number of turns in the electrode assembly 120. During the winding process of the electrode assembly 120, in the continuous layer structure formed by rotational winding with the winding axis L as the reference, the segment forming the innermost turn is the first turn segment of the electrode assembly 120, and the segment forming the outermost turn is the last turn segment of the electrode assembly 120. When the number of turns in the electrode assembly 120 is greater than or equal to three, the electrode assembly 120 includes an intermediate segment connecting the first turn segment and the last turn segment of the electrode assembly 120. When there are multiple intermediate segments in the electrode assembly 120, all the intermediate segments of the electrode assembly 120 are connected sequentially, with the first intermediate segment of the electrode assembly 120 connected to the first turn segment, and the last intermediate segment of the electrode assembly 120 connected to the last turn segment. The first loop segment Q1 of the main body 1211 is the portion of the main body 1211 located in the first loop segment of the electrode assembly 120, the last loop segment Q2 of the main body 1211 is the portion of the main body 1211 located in the last loop segment of the electrode assembly 120, and the middle loop segment Q3 of the main body 1211 is the portion of the main body 1211 located in the middle loop segment of the electrode assembly 120.

[0141] For example, with Figure 6 For example, the main body 1211 is illustrated as including a first segment Q1, a last segment Q2, and multiple intermediate segments Q3 connecting the first segment Q1 and the last segment Q2. Figure 6In the illustrated case, some intermediate ring segments Q3 are omitted for ease of illustration, and the various ring segments are distinguished by dashed lines. The dashed lines merely illustrate the division of the ring segments, and do not imply that there is a clear structural boundary in the actual structure. Of course, relevant boundaries can also be provided on the first pole tab 121 to distinguish the various ring segments, which are not specifically limited herein. It can be understood that the inlet end of the main body 1211 is the leading end of the first ring segment Q1 of the main body 1211, and the outlet end of the main body 1211 is the trailing end of the last ring segment of the main body 1211.

[0142] Please continue to refer to Figure 5 , and refer to Figure 7 , Figure 7 is a top view structural schematic diagram of the electrode assembly 120 in another illustrative case in some embodiments of the present application. It can be seen that the first ring segment Q1 and the last ring segment Q2 of the main body 1211 are each provided with a protrusion 1213. In Figure 5 and Figure 7 , the first tab 1212 and the protrusion 1213 are illustrated in different illustrative forms. Of course, the intermediate ring segment Q3 of the main body 1211 can also be provided with a protrusion 1213, or can not be provided with a protrusion 1213, which is not specifically limited herein. In Figure 4 , Figure 5 and Figure 7 , the case where the intermediate ring segment Q3 of the main body 1211 is also provided with a protrusion 1213 is illustrated. In addition, Figure 4 , the relative positions of the first tab 1212, the second tab 1221, and the protrusion 1213 are different from those illustrated in Figure 5 , Figure 7 . It can be understood that only different structural forms are provided, but this is not limited thereto.

[0143] Stiffness is the ability of a component to resist bending deformation, and is a performance parameter for measuring the ability of a component to maintain its shape (e.g., resistance to bending) when subjected to external forces. Stiffness can be used to characterize the mechanical properties of a component to resist deformation. The stiffness of the protrusion 1213 is greater than the stiffness of the first tab 1212, that is, the ability of the protrusion 1213 to resist deformation is stronger than the ability of the first tab 1212 to resist deformation. Illustratively, the stiffness of the protrusion 1213 can be adjusted by controlling the shape, structure, and size of the protrusion 1213, which is not specifically limited herein.

[0144] It should be noted that the stiffness of the component can be detected by simulating the bending force, quantifying the force value or deformation during bending. For example, cantilever beam method or four-point bending method can be used for detection. Taking the cantilever beam method as an example, one end of the component is fixed, a vertical force is applied to the free end of the component, and the force value required to bend the free end to a certain angle (such as 15°, 30° or other angles) is measured. The greater the force value, the higher the corresponding stiffness. No specific limitation is made herein.

[0145] With reference to Figure 8 and Figure 9 , Figure 8 is a structural schematic view of the comparison first pole piece 121' in an unfolded state in some comparative examples of the present application, Figure 9 is a top view structural schematic view of the comparison electrode assembly 120' in some comparative examples of the present application, in which only the first lug 1212 is provided on the comparison first pole piece 121' in the comparison electrode assembly 120' in some comparative examples of the present application, and no convex portion 1213 is provided. Again with reference to Figure 10 and Figure 11 , Figure 10 is a schematic view of the comparison electrode assembly 120' in some comparative examples of the present application in a state during the manufacturing process, Figure 11 is a schematic view of the comparison electrode assembly 120' in some comparative examples of the present application in another state during the manufacturing process, showing the situation of the comparison first pole piece 121' before and after feeding, when the image acquisition device 2000 acquires the image of the first lug 1212 of the comparison first pole piece 121' before feeding, in combination with Figure 10 and Figure 11 It can be seen that due to the existence of the image acquisition blind area W, the image acquisition device 2000 cannot acquire more accurate images. At the same time, before the comparison first pole piece 121' is fed, the feeding end of the comparison first pole piece 121' is a free end, and after the comparison first pole piece 121' is fed, the feeding end of the comparison first pole piece 121' is wound at the winding member 1000. During the feeding process, the tension of the comparison first pole piece 121' changes, so that the position of the first lug 1212 of the comparison first pole piece 121' is prone to change, and it is further difficult to acquire more accurate images. Similarly, during the feeding process of the comparison first pole piece 121', the comparison first pole piece 121' is cut off by the cutting device 3000, so that the tension of the feeding end of the comparison first pole piece 121' changes, and there is also an image acquisition blind area W, so that it is also impossible to acquire more accurate images.

[0146] In the embodiment of the present application, the stiffness of the convex portion 1213 is greater than that of the first tab 1212, so that when the tension changes due to the feeding and the collecting, the image can be collected based on the more stable state of the convex portion 1213, and thus a more accurate image can be collected, which is beneficial to determining more accurate feeding alignment and collecting alignment. Even if there is an image collection blind area W, because the convex portion 1213 can be in a more stable state, more accurate images can be collected before and after the feeding of the first tab 121, and before and after the collecting of the first tab 121.

[0147] It should be noted that the "feeding alignment" refers to the alignment of the first tab 121 and the second tab 122 at the first turn section of the electrode assembly 120, and the "collecting alignment" refers to the alignment of the first tab 121 and the second tab 122 at the last turn section of the electrode assembly 120.

[0148] Therefore, by arranging the convex portion 1213 at the first turn section Q1 and the last turn section Q2 of the main body portion 1211 of the first tab 121, and making the stiffness of the convex portion 1213 greater than that of the first tab 1212, the bending resistance of the convex portion 1213 is greater than that of the first tab 1212. Because there is no tension constraint when the head and the tail of the first tab 121 are cut off, the actual relative position of the first tab 121 and the second tab 122 may change during winding, which leads to inaccurate detection results of the tab alignment. In the embodiment of the present application, because the bending resistance of the convex portion 1213 is greater than that of the first tab 1212, the convex portion 1213 can be in a more stable state relative to the first tab 1212 when the tension changes, so that the feeding alignment and the collecting alignment of the electrode assembly 120 can be determined by using the convex portion 1213 which is less likely to be bent, thereby improving the detection accuracy of the feeding alignment and the collecting alignment, and further improving the detection accuracy of the alignment of the electrode assembly 120.

[0149] According to some embodiments of the present application, please continue to refer to Figure 6 The first tab 121 further comprises an insulating layer, and the insulating layer comprises a first insulating portion 12141 and a second insulating portion 12142 connected with the first insulating portion 12141. The edge region of one side of the convex portion 1213 of the main body portion 1211 is a first region Z1, and the root region of the first tab 1212 adjacent to the main body portion 1211 is a second region Z2. The first insulating portion 12141 is arranged at the first region Z1, and the second insulating portion 12142 is arranged at the second region Z2 and covers at least part of the convex portion 1213.

[0150] In the Figure 6 , the positions of the first region Z1 and the second region Z2 are shown in dashed lines.

[0151] The insulating layer is a layer for insulation protection. Exemplarily, the insulating layer comprises inorganic fillers and a binder. The inorganic fillers comprise one or more of boehmite, alumina, magnesia, titania, zirconia, silica, silicon carbide, boron carbide, calcium carbonate, aluminum silicate, calcium silicate, potassium titanate, barium sulfate. The binder comprises one or more of polyvinylidene fluoride, polyacrylonitrile, polyacrylic acid, polyacrylate, polyacrylic acid-acrylate, polyacrylonitrile-acrylic acid, polyacrylonitrile-acrylate.

[0152] Exemplarily, the thickness of the insulating layer can be 80 μm to 200 μm. For example, the thickness of the insulating layer can be 80 μm, 90 μm, 100 μm, 110 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm or 200 μm. The thickness of the insulating layer can be any value within 80 μm to 200 μm, which is not specifically limited herein.

[0153] The second insulating portion 12142 can cover part or all of the convex portion 1213, which is not specifically limited herein. For example, the second insulating portion 12142 covers part of the convex portion 1213. Figure 6 For example, the second insulating portion 12142 covers part of the convex portion 1213. Figure 12 For example, Figure 12 For example, the second insulating portion 12142 covers part of the convex portion 1213.

[0154] Exemplarily, for example, Figure 12 and Figure 13 For example, Figure 13 For example, the second insulating portion 12142 covers part of the convex portion 1213.

[0155] By providing the insulating layer, insulation protection can be achieved. Even if the first tab 1212 is inserted between the first tab 1212 and the second tab 122, the first tab 1212 and the second tab 122 can be separated by the insulating layer, thereby reducing the risk of short circuit and improving safety performance. Since the insulating layer has a certain thickness, the thickness of the area of the first tab 121 covered by the insulating layer can be increased, the cross-sectional moment of inertia can be increased, thereby increasing the stiffness of the area of the first tab 121 covered by the insulating layer, which is conducive to further improving the stiffness of the convex portion 1213, and further improving the detection accuracy of the in-roll alignment and the roll alignment.

[0156] It should be noted that the stiffness of the convex portion 1213 can be adjusted by controlling the material, thickness and covered area of the insulating layer, which is not specifically limited here.

[0157] According to some embodiments of the present application, please continue to refer to Figure 6 , Figure 12 and Figure 13 , the convex portion 1213 includes a first surface m1 and a second surface m2 oppositely arranged along the thickness direction of the convex portion 1213. The thickness direction of the convex portion 1213 is perpendicular to the winding axis direction J1 of the electrode assembly 120. Among them, the ratio of the area of the first surface m1 covered by the second insulating portion 12142 to the area of the first surface m1 is 0.8 to 1; and / or, the ratio of the area of the second surface m2 covered by the second insulating portion 12142 to the area of the second surface m2 is 0.8 to 1.

[0158] For example, the ratio of the area of the first surface m1 covered by the second insulating portion 12142 to the area of the first surface m1 can be 0.8, 0.81, 0.83, 0.86, 0.9, 0.92, 0.94, 0.97 or 1. Of course, the ratio of the area of the first surface m1 covered by the second insulating portion 12142 to the area of the first surface m1 can be any value within the range of 0.8 to 1, which is not specifically limited here. The ratio of the area of the second surface m2 covered by the second insulating portion 12142 to the area of the second surface m2 can be 0.8, 0.81, 0.83, 0.86, 0.9, 0.92, 0.94, 0.97 or 1. Of course, the ratio of the area of the second surface m2 covered by the second insulating portion 12142 to the area of the second surface m2 can be any value within the range of 0.8 to 1, which is not specifically limited here. It can be understood that the more area covered by the insulating layer on the convex portion 1213, the more conducive to improving the stiffness of the convex portion 1213.

[0159] By controlling the area ratio of the first surface m1 and / or the second surface m2 of the convex portion 1213 covered by the second insulating portion 12142, the stiffness of the convex portion 1213 can be further improved, and the detection accuracy of the in-roll alignment and the winding alignment can be further improved.

[0160] According to some embodiments of the present application, please continue to refer to Figure 6 , Figure 12 and Figure 13 , the ratio of the surface area of the area covered by the second insulating portion 12142 to the surface area of the convex portion 1213 is 0.8 to 1.

[0161] For example, the ratio of the surface area of the area of the convex portion 1213 covered by the second insulating portion 12142 to the surface area of the convex portion 1213 can be 0.8, 0.81, 0.83, 0.86, 0.9, 0.92, 0.94, 0.97, or 1. Of course, the ratio of the surface area of the area of the convex portion 1213 covered by the second insulating portion 12142 to the surface area of the convex portion 1213 can be any value in the range of 0.8 to 1, which is not specifically limited herein. It can be understood that the more the area of the convex portion 1213 covered by the insulating layer, the more conducive to improving the stiffness of the convex portion 1213.

[0162] The size of the area of the first surface m1 of the convex portion 1213 covered by the insulating layer and the size of the area of the second surface m2 of the convex portion 1213 covered by the insulating layer can be the same or different, which is not specifically limited herein. In the embodiments of the present application, the size of the area of the first surface m1 of the convex portion 1213 covered by the insulating layer and the size of the area of the second surface m2 of the convex portion 1213 covered by the insulating layer are the same. In this way, it is conducive to manufacturing the insulating layer and the convex portion 1213.

[0163] By controlling the area ratio of the area of the convex portion 1213 covered by the second insulating portion 12142, the stiffness of the convex portion 1213 can be further improved, and the detection accuracy of the roll-in alignment and the roll alignment can be further improved.

[0164] According to some embodiments of the present application, please continue to refer to Figure 6 , Figure 12 and Figure 13 , the size of the convex portion 1213 is smaller than the size of the first tab 1212 along the winding axis direction J1 of the electrode assembly 120; and / or, the size of the convex portion 1213 is smaller than the size of the first tab 1212 along the winding direction J2 of the electrode assembly 120.

[0165] The size of the convex portion 1213 is a first size d1 along the winding axis direction J1 of the electrode assembly 120. The size of the first tab 1212 is a second size d2 along the winding axis direction J1 of the electrode assembly 120. That is, the first size d1 is smaller than the second size d2. The size of the convex portion 1213 is a third size d3 along the winding direction J2 of the electrode assembly 120. The size of the first tab 1212 is a fourth size d4 along the winding direction J2 of the electrode assembly 120. That is, the third size d3 is smaller than the fourth size d4.

[0166] In this way, by controlling the size of the convex portion 1213 along the winding axis direction J1 of the electrode assembly 120 and / or along the winding direction J2 of the electrode assembly 120, the size of the convex portion 1213 is substantially smaller than the first tab 1212, thereby facilitating adjustment of the stiffness of the convex portion 1213.

[0167] According to some embodiments of the present application, please continue to refer to Figure 6 The ratio of the dimension of the protrusion 1213 along the winding direction J2 of the electrode assembly 120 to the dimension of the protrusion 1213 along the winding axis direction J1 of the electrode assembly 120 is greater than or equal to 7.

[0168] That is, the ratio of the third dimension d3 to the first dimension d1 is greater than or equal to 7. For example, the ratio of the third dimension d3 to the first dimension d1 can be 7, 8, 9, 10, or 15. The upper limit of the ratio of the third dimension d3 to the first dimension d1 can be determined according to the first dimension d1. As shown in some embodiments described above, the first dimension d1 is less than the second dimension d2. That is, the ratio of the third dimension d3 to the second dimension d2 is less than 7. No specific limitation is made herein.

[0169] By controlling the ratio of the dimension of the protrusion 1213 along the winding direction J2 of the electrode assembly 120 to the dimension of the protrusion 1213 along the winding axis direction J1 of the electrode assembly 120, the stiffness of the protrusion 1213 is further adjusted.

[0170] It should be noted that in the case of “the dimension of the protrusion 1213 along the winding axis direction J1 of the electrode assembly 120 is less than the dimension of the first tab 1212”, “the dimension of the protrusion 1213 along the winding direction J2 of the electrode assembly 120 is less than the dimension of the first tab 1212”, and “the ratio of the dimension of the protrusion 1213 along the winding direction J2 of the electrode assembly 120 to the dimension of the protrusion 1213 along the winding axis direction J1 of the electrode assembly 120 is greater than or equal to 7”, the protrusion 1213 can have a small height and a large lateral dimension, so that the protrusion 1213 is roughly provided in a short and thick shape, thereby facilitating the improvement of the stiffness of the protrusion 1213.

[0171] According to some embodiments of the present application, please continue to refer to Figure 4 , Figure 5 and Figure 7 The electrode assembly 120 has a reference surface E, and the winding axis L of the electrode assembly 120 is located on the reference surface E. The reference surface E has oppositely arranged first and second sides, and the plurality of first tabs 1212 is located on the first side, and all the protrusions 1213 are located on the second side.

[0172] In the perspective of Figure 5 and Figure 7 , the reference surface E is provided in a linear shape, and the winding axis L is provided in a point shape.

[0173] By arranging the first tabs 1212 and the protrusions 1213 on different sides, all the first tabs 1212 can be arranged in the same area, which not only facilitates the connection of all the first tabs 1212 to the electrode terminal 1121 of the battery monomer 100, but also facilitates the improvement of the space utilization.

[0174] Of course, in some other embodiments, a part of the first tab 1212 and a part of the protrusion 1213 can be located on the first side, and another part of the first tab 1212 and another part of the protrusion 1213 can be located on the second side. No specific limitation is made herein.

[0175] According to some embodiments of the present application, please continue to refer to Figure 4 , Figure 5 and Figure 7 , the orthographic projection of all protrusions 1213 on the reference surface E has an overlapping part with the orthographic projection of the plurality of first tabs 1212 on the reference surface E.

[0176] That is, in the third direction F3 as shown in Figure 4 , Figure 5 and Figure 7 , the protrusion 1213 and the first tab 1212 have an overlapping part. The orthographic projection of all protrusions 1213 on the reference surface E can partially overlap or fully overlap with the orthographic projection of the plurality of first tabs 1212 on the reference surface E. No specific limitation is made herein.

[0177] In this way, the protrusion 1213 can provide a supporting force to support the first tab 1212, thereby reducing the risk of short circuit caused by the insertion of the first tab 1212 between the first and second tab plates 121 and 122 during the process of installing the electrode assembly 120 into the shell 110 of the battery cell 100 after the first tab 1212 is connected to the electrode terminal 1121 of the battery cell 100, thereby reducing the risk of tab redundancy and improving safety performance.

[0178] It should be noted that when the plurality of electrode assemblies 120 are combined and assembled into the shell 110 of the battery cell 100, tab redundancy may occur due to factors such as process and jig interference. In the embodiments of the present application, the protrusion 1213 is arranged on the opposite side of the first tab 1212, thereby supporting the first tab 1212.

[0179] According to some embodiments of the present application, please continue to refer to Figure 4 , Figure 5 and Figure 7 , the orthographic projection of any protrusion 1213 of all protrusions 1213 on the reference surface E has an overlapping part with the orthographic projection of any first tab 1212 of the plurality of first tabs 1212 on the reference surface E; and / or, the number of the loop segments of the main body 1211 is M, and the number of the loop segments provided with the protrusion 1213 is N; wherein 0.5≤N / M≤1, and N and M are positive integers.

[0180] The normal projection of any one of the protrusions 1213 on the reference surface E has an overlapping portion with the normal projection of any one of the first tabs 1212 on the reference surface E, that is, all the first tabs 1212 and all the protrusions 1213 can be seen as being arranged in a stacked manner in the third direction F3. It can be understood that the more protrusions 1213 stacked with the first tabs 1212, the more conducive to improving the supporting effect on the first tabs 1212. Figure 4 , Figure 5 and Figure 7 The normal projection of any one of the protrusions 1213 on the reference surface E has an overlapping portion with the normal projection of any one of the first tabs 1212 on the reference surface E, that is, all the first tabs 1212 and all the protrusions 1213 can be seen as being arranged in a stacked manner in the third direction F3. It can be understood that the more protrusions 1213 stacked with the first tabs 1212, the more conducive to improving the supporting effect on the first tabs 1212.

[0181] “0.5≤N / M≤1”, that is, most of the circle segments are provided with protrusions 1213. For example, the ratio of N / M can be 0.5, 0.8 or 1, which is not limited herein. Figure 4 and Figure 5 For example, the number of circle segments of the electrode assembly 120 is three, and each circle segment is provided with a protrusion 1213. That is, the first circle segment Q1, the middle circle segment Q3 and the last circle segment Q2 of the main body 1211 are all provided with protrusions 1213. It can be understood that the more circle segments provided with protrusions 1213, the more conducive to arranging the protrusions 1213 in a stacked manner as described above, thereby more conducive to improving the supporting effect on the first tabs 1212.

[0182] In this way, each protrusion 1213 can provide a supporting force acting on the first tabs 1212, thereby further improving the supporting effect on the first tabs 1212 and further reducing the risk of tab redundancy. By controlling the number of circle segments provided with protrusions 1213, the protrusions 1213 can have a certain supporting effect on the first tabs 1212.

[0183] Of course, in some other embodiments, the protrusions 1213 can not be stacked with the first tabs 1212 in the third direction F3, which is not limited herein.

[0184] According to some embodiments of the present application, please continue to refer to Figure 7 The middle circle segment Q3 of the main body 1211 is provided with at least one protrusion 1213.

[0185] In this way, since the at least one middle circle segment Q3 is provided with a protrusion 1213, the alignment of the middle circle segment Q3 can be verified by using the protrusion 1213 arranged on the middle circle segment Q3, thereby being conducive to further improving the detection accuracy of the alignment of the electrode assembly 120. When the normal projection of the protrusion 1213 on the reference surface E has an overlapping portion with the normal projection of the first tab 1212 on the reference surface E, it is conducive to improving the supporting performance of the protrusion 1213 on the first tab 1212.

[0186] According to some embodiments of the present application, please continue to refer to Figure 4 The intermediate ring segment Q3 is provided as multiple ring segments, and each intermediate ring segment Q3 is provided with a protrusion 1213.

[0187] In this way, the protrusion 1213 of each intermediate ring segment Q3 can be used to check the alignment of the intermediate ring segment Q3, thereby further facilitating the detection accuracy of the alignment of the electrode assembly 120. Of course, when the orthogonal projection of the protrusion 1213 on each intermediate ring segment Q3 on the reference surface E has an overlapping portion with the orthogonal projection of the first tab 1212 on the reference surface E, it is further beneficial to improve the support performance of the protrusion 1213 on the first tab 1212.

[0188] It should be noted that in combination with reference to Figure 5 and Figure 7 , Figure 4 is a cross-sectional structure schematic diagram of part of the structure of the battery monomer 100 in some embodiments of the present application, Figure 5 is an image schematic diagram of part of the structure of the battery monomer 100 in some embodiments of the present application, the first tab 1212 is connected with the electrode terminal 1121. Since the protrusion 1213 can support the first tab 1212, the first tab 1212 can be better kept in a redundant state after the two electrode assemblies 120 are installed in the shell 110. In combination with reference to Figure 7 , Figures 4 to 7 , Figures 4 to 7 and Figure 14 , since the protrusion 1213 is not provided, the first tab 1212 generates redundancy after the two comparative electrode assemblies 120' are installed in the shell 110. Referring to the redundant area A in the figure, there is a risk of short circuit between the first tab 121 and the second tab 122. Therefore, in the embodiments of the present application, the protrusion 1213 is used to support the first tab 1212, which can reduce the risk of tab redundancy and improve the safety performance of the battery.

[0189] According to some embodiments of the present application, please continue to refer to Figure 15 , Figure 14 and Figure 15 , along the winding direction J2 of the electrode assembly 120, the same number of first tabs 1212 are arranged between every two adjacent protrusions 1213.

[0190] In the cases shown in Figure 8 , Figure 9 and Figure 16 , one first tab 1212 is arranged between every two adjacent protrusions 1213. Of course, two first tabs 1212, three first tabs 1212 or other numbers of first tabs 1212 can also be arranged between every two adjacent protrusions 1213, which is not specifically limited here.

[0191] Since the distribution of the convex portions 1213 and the first tabs 1212 has periodicity, not only can the tension for winding the electrode assembly 120 be more balanced along the circumferential direction of the winding 1000, thereby improving the stability of the winding formation, but also the automated manufacturing of the first tabs 1212 and the convex portions 1213 is facilitated.

[0192] Of course, in some other embodiments, along the winding direction J2 of the electrode assembly 120, different numbers of the first tabs 1212 can be arranged between every two adjacent convex portions 1213. No specific limitation is made herein.

[0193] According to some embodiments of the present application, please continue to refer to Figure 17 , Figures 5 to 7 and Figure 12 , the convex portions 1213 are orthographically projected on a plane perpendicular to the thickness direction of the convex portions 1213 as first projections, and the thickness direction of the convex portions 1213 is perpendicular to the winding axis direction J1 of the electrode assembly 120. The shapes of all the first projections include at least one of a rectangle, a square, a rhombus, and a trapezoid.

[0194] The shapes of all the convex portions 1213 can be the same or different. For example, Figure 13 , Figures 5 to 7 and Figure 12 are used to illustrate the case where the shapes of all the convex portions 1213 are the same. In the cases illustrated in Figure 13 , Figure 6 and Figure 12 , the convex portions 1213 are roughly rectangular bodies.

[0195] In this way, by controlling the shapes of the convex portions 1213, the manufacturing convenience is improved while the convex portions 1213 have certain mechanical properties.

[0196] According to some embodiments of the present application, along the winding direction J2 of the electrode assembly 120, the size of the convex portions 1213 along the winding axis direction J1 of the electrode assembly 120 changes in a first regularity. The first regularity includes one of being constant, first decreasing and then increasing, first increasing and then decreasing, first decreasing and then increasing and then decreasing, and first increasing and then decreasing and then increasing.

[0197] For example, Figure 13 , Figure 6 and Figure 12 are used to illustrate the case where the size of the convex portions 1213 along the winding axis direction J1 of the electrode assembly 120 is constant along the winding direction J2 of the electrode assembly 120.

[0198] When the first rule is constant, it is beneficial to make the convex portion 1213 have certain mechanical properties while facilitating the manufacture of the convex portion 1213. When the first rule includes one of decreasing first and then increasing, increasing first and then decreasing, decreasing first and then increasing and then decreasing, and increasing first and then decreasing and then increasing, it is beneficial to control mechanical stress through the morphological change of the convex portion 1213, thereby improving the reliability of the convex portion 1213.

[0199] According to some embodiments of the present application, along the winding axis direction J1 of the electrode assembly 120, the size of the convex portion 1213 along the winding direction J2 of the electrode assembly 120 changes according to a second rule. The second rule includes one of constant, decreasing, increasing, decreasing first and then increasing, increasing first and then decreasing, decreasing first and then increasing and then decreasing, and increasing first and then decreasing and then increasing.

[0200] For example, along the winding axis direction J1 of the electrode assembly 120, the size of the convex portion 1213 along the winding direction J2 of the electrode assembly 120 is constant. Figure 13 、 Figure 6 and Figure 12 For example, along the winding axis direction J1 of the electrode assembly 120, the size of the convex portion 1213 along the winding direction J2 of the electrode assembly 120 is constant.

[0201] When the second rule is constant, it is beneficial to make the convex portion 1213 have certain mechanical properties while facilitating the manufacture of the convex portion 1213. When the second rule includes one of decreasing, increasing, decreasing first and then increasing, increasing first and then decreasing, decreasing first and then increasing and then decreasing, and increasing first and then decreasing and then increasing, it is beneficial to control mechanical stress through the morphological change of the convex portion 1213, thereby improving the reliability of the convex portion 1213.

[0202] According to some embodiments of the present application, please continue to refer to Figure 13 , the size of the convex portion 1213 along the winding axis direction J1 of the electrode assembly 120 is 2mm to 6mm; and / or, the size of the convex portion 1213 along the winding direction J2 of the electrode assembly 120 is 5mm to 9mm.

[0203] For example, the size of the convex portion 1213 along the winding axis direction J1 of the electrode assembly 120 is a first size d1, and the first size d1 can be 2mm, 3mm, 4mm, 5mm or 6mm. The first size d1 can be any value within the range of 2mm to 6mm, which is not limited here.

[0204] For example, the size of the convex portion 1213 along the winding direction J2 of the electrode assembly 120 is a third size d3, and the third size d3 can be 5mm, 6mm, 7mm, 8mm or 9mm. The third size d3 can be any value within the range of 5mm to 9mm.

[0205] The dimension of the protrusion 1213 along the winding axis direction J1 of the electrode assembly 120 can be regarded as the height dimension of the protrusion 1213, and the dimension of the protrusion 1213 along the winding direction J2 of the electrode assembly 120 can be regarded as the width dimension of the protrusion 1213. It can be understood that the aforementioned height dimension of the protrusion 1213 and the width dimension of the protrusion 1213 do not limit the placement manner of the electrode assembly 120, but are only used to distinguish the two dimensions of the protrusion 1213. By controlling the height and / or width of the protrusion 1213, not only the manufacturing of the protrusion 1213 is facilitated, but also the protrusion 1213 has certain mechanical reliability and is adapted to the space limitation in the winding process.

[0206] According to some embodiments of the present application, the first tab 121 is a positive electrode tab, and the second tab 122 is a negative electrode tab.

[0207] In this way, the positive electrode tab can include the first tab 1212 and the protrusion 1213. Since the overall rigidity of the positive electrode tab is greater than that of the negative electrode tab, the stability of the protrusion 1213 is improved, and the detection accuracy of the alignment degree is improved. At the same time, since the size of the negative electrode tab is usually slightly larger than that of the positive electrode tab, taking the protrusion 1213 on the positive electrode tab as a detection reference, it can be more direct to judge whether the negative electrode tab effectively covers the positive electrode tab.

[0208] Of course, in some other embodiments, the first tab 121 can be a negative electrode tab, and the second tab 122 can be a negative electrode tab.

[0209] According to some embodiments of the present application, please refer to Figure 6 , Figure 12 FIG. 1 is a flow diagram of a method for manufacturing a battery cell according to some embodiments of the present application. The present application provides a method for manufacturing a battery cell, which includes the following steps:

[0210] S110, providing a first tab, a second tab, and a separator; the first tab includes a main body portion, a plurality of first tabs, and a protrusion respectively arranged at a first circle segment and a last circle segment of the main body portion; along the width direction of the first tab, the plurality of first tabs and all the protrusions are arranged on the same side of the main body portion, and the stiffness of the protrusion is greater than the stiffness of the first tab;

[0211] S120, laminating and winding the separator, the first tab, and the second tab to form an electrode assembly;

[0212] S130, in the case that the in-winding alignment degree and the winding alignment degree of the first tab and the second tab both satisfy the alignment degree qualified condition, the electrode assembly is loaded into the accommodating cavity of the shell to form a battery cell; wherein the in-winding alignment degree is determined based on the protrusion located at the first circle segment of the main body portion, and the winding alignment degree is determined based on the protrusion located at the last circle segment of the main body portion.

[0213] In step S110, the first tab sheet provided by the first tab sheet strip roll can include the first tab and the protrusion, or the first tab and the protrusion can be formed by a die-cutting process during the process of conveying the first tab sheet from the first tab sheet strip roll, which is not specifically limited herein. The second tab sheet and the separator can also be provided by corresponding strip rolls. For the related embodiments of the first tab sheet, the second tab sheet and the separator, and the stiffness of the protrusion and the stiffness of the first tab, reference can be made to the contents shown in some of the foregoing embodiments, which will not be repeated here.

[0214] In step S120, for example, in combination with the foregoing Figure 13 and Figure 6 , Figure 12 is a schematic view of an electrode assembly in some embodiments of the present application in a state during the manufacturing process, Figure 13 is a schematic view of an electrode assembly in some embodiments of the present application in another state during the manufacturing process, the first tab sheet 121 is a positive electrode tab sheet, the second tab sheet 122 is a negative electrode tab sheet, and they can be stacked into a roll in the order of “first tab sheet 121 → separator 123 → second tab sheet 122 → separator 123” to form a stacked body. Through the rotation of the winding member 1000, the stacked body is wound to form a wound body. In the winding stage, the wound body can be cut by the cutting device 3000 to form the electrode assembly 120. In the process of forming the electrode assembly 120, the first tab sheet 121, the separator 123 and the second tab sheet 122 are conveyed by the conveying device 4000. Among them, the winding member 1000 can be a winding needle, and the conveying device 4000 can be a roller assembly.

[0215] In step S130, the entry alignment and the winding alignment can be understood in combination with the foregoing embodiments, which will not be repeated here. The alignment qualified condition is a condition set based on the required alignment of the electrode assembly. The alignment qualified condition can be an alignment range, and when the entry alignment and the winding alignment are within the alignment range, it means that the entry alignment and the winding alignment are qualified. When both the entry alignment and the winding alignment meet the alignment qualified condition, it means that the alignment of the first tab sheet and the second tab sheet at the first turn section of the electrode assembly and the alignment of the first tab sheet and the second tab sheet at the last turn section of the electrode assembly meet the alignment qualified condition, and the electrode assembly is qualified. When either of the entry alignment and the winding alignment does not meet the alignment qualified condition, it means that the electrode assembly is unqualified.

[0216] After the qualified electrode assembly is loaded into the receiving cavity of the shell, a battery cell can be formed through the steps of liquid injection, packaging of the shell, etc., which will not be repeated here.

[0217] In the technical solution of the embodiment of the application, the convex part is arranged on the first circle segment and the last circle segment of the main body part of the first tab, and the stiffness of the convex part is greater than the stiffness of the first tab, so that the bending resistance of the convex part is greater than the bending resistance of the first tab. Since the head part and the tail part of the first tab are not bound by tension when being cut off, the actual relative position of the first tab and the second tab may change when being wound, so that the result of the alignment detection of the tab is inaccurate. In the embodiment of the application, when the tension changes, the convex part can be in a more stable state relative to the first tab because the bending resistance of the convex part is greater than the bending resistance of the first tab when the electrode assembly is manufactured, so that the winding alignment and the winding alignment of the electrode assembly can be determined by using the convex part which is less likely to be bent, the detection accuracy of the winding alignment and the winding alignment is improved, and the detection accuracy of the alignment of the electrode assembly is further improved.

[0218] According to some embodiments of the application, please refer to Figure 6 , Figure 18 The flowchart of steps SI, SJ and SK in the manufacturing method of the battery cell in some embodiments of the application, the manufacturing method of the battery cell further includes the following steps:

[0219] SI, obtaining the first image of the convex part located on the first circle segment of the main body part and the main body part before the first tab is wound; determining the first distance between the convex part located on the first circle segment of the main body part and the main body part in the width direction of the first tab according to the first image;

[0220] SJ, obtaining the second image of the convex part located on the first circle segment of the main body part and the main body part after the first tab is wound on the winding part; determining the second distance between the convex part located on the first circle segment of the main body part and the second tab in the width direction of the first tab according to the second image;

[0221] SK, determining whether the winding alignment meets the alignment qualified condition based on the difference between the first distance and the second distance.

[0222] The above steps SI, SJ and SK are executed in the process of forming the electrode assembly.

[0223] In step SI, for example, please continue to refer to Figure 18 and Figure 19 The image acquisition device 2000 includes a first image acquisition component 2100 for acquiring the first image. For example, the first image acquisition component 2100 can be a camera. For a better understanding, please refer to Figure 20 and Figure 19 , Figure 20 The schematic diagram of the first image in some embodiments of the application is shown in Figure 21For the schematic view of the part of the first electrode tab 121 corresponding to the first image in some embodiments of the present application, the first distance h1 can be the distance between the side edge of the protrusion 1213 away from the main body part 1211 and the side edge of the insulating layer on the main body part 1211 away from the protrusion 1213. A processor (not shown in the figure) electrically connected to the first image acquisition component 2100 can be provided, and the processor is configured to determine the first distance h1 according to the first image. It should be noted that, Figure 21 The first image shown in the schematic view is only a part of the structure. Figure 19 The first image shown in the schematic view is only a part of the structure.

[0224] In step SJ, for example, please continue to refer to Figure 20 and Figure 22 The image acquisition device 2000 further comprises a second image acquisition component 2200 configured to acquire a second image. For example, the second image acquisition component 2200 can be a camera. For a better understanding, Figure 23 and Figure 22 , Figure 23 For the schematic view of the second image in some embodiments of the present application, Figure 22 For the schematic view of the part of the wound electrode assembly 120 corresponding to the second image in some embodiments of the present application, the second distance h2 can be the distance between the side edge of the protrusion 1213 away from the main body part 1211 and the edge of the second electrode tab 122 arranged towards the protrusion 1213. The aforementioned processor can be electrically connected to the second image acquisition component 2200, and the processor is configured to determine the second distance h2 according to the second image. It should be noted that, Figure 23 The first image shown in the schematic view is only a part of the structure. Figure 19 The first image shown in the schematic view is only a part of the structure.

[0225] In step SK, for example, please continue to refer to Figure 20 and Figure 24 Since the first distance h1 and the second distance h2 are determined based on the same protrusion 1213 located on the first turn segment Q1 of the main body part 1211, the difference between the first distance h1 and the second distance h2 can be used to represent the winding alignment of both the first electrode tab 121 and the second electrode tab 122. The processor can also be configured to determine whether the winding alignment meets the alignment qualification condition according to the first distance h1 and the second distance h2.

[0226] During the winding process of the first electrode tab, the tension of the first electrode tab will change. Since the protrusion located on the first turn segment of the main body part can be in a more stable state, the first distance between the protrusion located on the first turn segment of the main body part and the main body part determined is more accurate, which is conducive to improving the accuracy of detecting the winding alignment.

[0227] According to some embodiments of the present application, please refer to Figure 25 , Figure 24 FIG. 6 is a flowchart of a method for manufacturing a battery cell according to some embodiments of the present application. The method for manufacturing a battery cell includes the following steps:

[0228] SF, obtaining a third image of the protrusion at the end section of the main body portion and the main body portion before winding the end section of the main body portion; and determining, according to the third image, a third distance between the protrusion at the end section of the main body portion and the main body portion in the width direction of the first electrode tab;

[0229] SG, obtaining a fourth image of the protrusion at the end section of the main body portion and the main body portion after winding the end section of the main body portion; and determining, according to the fourth image, a fourth distance between the protrusion at the end section of the main body portion and the second electrode tab in the width direction of the first electrode tab;

[0230] SH, determining whether the winding alignment meets the alignment qualification condition based on a difference between the third distance and the fourth distance.

[0231] In step SF, the third image can be collected by the first image collection component 2100 as shown in the foregoing, and the processor is configured to determine the third distance h3 according to the third image. For example, please refer to Figure 25 , Figure 24 FIG. 6 is a flowchart of a method for manufacturing a battery cell according to some embodiments of the present application. The method for manufacturing a battery cell includes the following steps:

[0232] In step SG, the fourth image can be collected by the second image collection component 2200 as shown in the foregoing, and the processor is configured to determine the fourth distance h4 according to the fourth image. For example, please refer to Figure 25 , Figure 23 FIG. 6 is a flowchart of a method for manufacturing a battery cell according to some embodiments of the present application. The method for manufacturing a battery cell includes the following steps:

[0233] In step SH, please refer to Figure 25 and Figure 26Since the third distance h3 and the fourth distance h4 are determined based on the same protrusion 1213 located on the last coil segment Q2 of the main body part 1211, the difference between the third distance h3 and the fourth distance h4 can be used to represent the winding alignment of both the first pole piece 121 and the second pole piece 122. The processor can also be configured to determine whether the winding alignment satisfies the alignment qualified condition according to the third distance h3 and the fourth distance h4.

[0234] During the winding process of the first pole piece, the tension of the first pole piece changes. Since the protrusion located on the last coil segment of the main body part can be in a more stable state, the third distance between the protrusion located on the last coil segment of the main body part and the main body part determined is more accurate, which is beneficial to improve the accuracy of the detected winding alignment.

[0235] According to some embodiments of the present application, a protrusion is arranged on the middle coil segment of the main body part. Please refer to Figure 26 , Figure 27 The flowchart of the steps SO, SP and SQ in the manufacturing method of the battery cell in some embodiments of the present application is shown in the figure. The manufacturing method of the battery cell further includes the following steps:

[0236] SO, based on the check alignment of the first pole piece and the second pole piece, the reference alignment of the first pole piece and the second pole piece is checked. The reference alignment is determined based on the first tab located on the middle coil segment of the main body part, and the check alignment is determined based on the protrusion located on the middle coil segment of the main body part.

[0237] SP, in the case that the winding alignment and the winding alignment both satisfy the alignment qualified condition, and the reference alignment satisfies the check qualified condition, the electrode assembly is loaded into the accommodating cavity of the shell to form the battery cell.

[0238] In step SO, the check alignment of the middle coil segment determined by the protrusion located on the middle coil segment of the main body part can be determined according to the determination of the winding alignment and the winding alignment in some embodiments described above, which is not limited here.

[0239] In step SP, for the electrode assembly that satisfies the alignment qualified condition and the check qualified condition, that is, the winding alignment, the winding alignment and the alignment of the middle coil segment of the electrode assembly are all determined to satisfy the corresponding conditions, so that the alignment of each part of the electrode assembly satisfies the requirements.

[0240] In this way, the check alignment is obtained by the protrusion arranged on the middle coil segment, which can further improve the accuracy of the alignment of the middle coil segment.

[0241] It should be noted that the first image acquisition component 2100 and the second image acquisition component 2200 shown in the foregoing embodiments can include a linear array camera and a planar array camera. In addition, based on the acquired image, edge detection processing can be performed to obtain a corresponding edge line, and then the processor can determine the corresponding distance and whether the corresponding condition is met according to the obtained corresponding edge line. The technical logic of the edge detection processing can include gradient calculation, convolution operation on the image by a specific operator, and the like, which is not specifically limited here.

[0242] Of course, in some other embodiments, in the case that any one of the winding alignment degree and the winding alignment degree does not meet the alignment qualified condition, a warning information can be output to facilitate the operator to perform the related operation. Further, the unqualified electrode assembly can be placed in an unqualified area to facilitate subsequent destruction or repair of the unqualified electrode assembly. In the case that the verification qualified condition is not met, the foregoing embodiments can also be implemented, which is not specifically limited here.

[0243] According to some embodiments of the present application, please refer to Figure 27 , Figure 28 Figure 28 Figure 27 Figure 28 Figure 29 Figure 29 Figure 30 Figure 30 FIG. 1 is a flowchart of steps S111 and S112 in some embodiments of the present application, and FIG. 2 is a schematic diagram of a process of providing a first electrode sheet, a second electrode sheet and a separator according to some embodiments of the present application. The process includes the following steps:

[0244] S111, providing a first electrode sheet strip;

[0245] S112, die cutting the first electrode sheet strip to form a plurality of first electrode tabs and all convex portions to obtain a first electrode sheet.

[0246] In this way, the first electrode tab and the convex portion can be manufactured by the same process, which not only utilizes the structure of the first electrode sheet to manufacture the convex portion, thereby improving the convenience of manufacturing the convex portion, but also helps to improve the production efficiency.

[0247] According to some embodiments of the present application, the method for manufacturing a battery cell further includes:

[0248] When the first electrode sheet is wound at the inlet end, an acting force acting on the inlet end of the first electrode sheet away from the winding member is provided to enable the inlet end of the first electrode sheet to be close to the winding member.

[0249] For example, a blowing mechanism can be provided to provide the air flow acting force.

[0250] In this way, by providing the acting force acting on the inlet end of the first electrode sheet, the inlet end of the first electrode sheet can be more stably and reliably fed, thereby reducing the risk of wrinkles, bending and the like at the inlet end of the first electrode sheet, and thus helping to improve the performance of the electrode assembly.

[0251] According to some embodiments of the present application, the embodiments of the present application provide a battery device comprising the battery cell in any of the above embodiments; or the battery cell manufactured by the manufacturing method of the battery cell in any of the above embodiments.

[0252] The battery device also has the advantages of the battery cell in any of the above embodiments and the battery cell manufactured by the manufacturing method of the battery cell in any of the above embodiments, which will not be repeated here.

[0253] According to some embodiments of the present application, the embodiments of the present application provide a battery device comprising the battery cell in any of the above embodiments; or the battery cell manufactured by the manufacturing method of the battery cell in any of the above embodiments.

[0254] The battery device also has the advantages of the battery cell in any of the above embodiments and the battery cell manufactured by the manufacturing method of the battery cell in any of the above embodiments, which will not be repeated here.

[0255] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the above embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. Especially, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, The electrode assembly includes a first tab, a second tab, and a separator separating the first tab and the second tab; The first tab includes a main body, a plurality of first tabs, and a protrusion provided at a first circle segment and a last circle segment of the main body; along the winding axis direction of the electrode assembly, the plurality of first tabs and all the protrusions are provided on the same side of the main body, the stiffness of the protrusion is greater than the stiffness of the first tab; along the winding axis direction of the electrode assembly, the size of the protrusion is smaller than the size of the first tab; along the winding direction of the electrode assembly, the size of the protrusion is smaller than the size of the first tab; The electrode assembly has a reference surface, and the winding axis of the electrode assembly is located on the reference surface; The reference surface has a first side and a second side arranged opposite to each other, and the plurality of first tabs are located on the first side, and all the protrusions are located on the second side; The normal projection of all the protrusions on the reference surface has an overlapping part with the normal projection of the plurality of first tabs on the reference surface.

2. The battery cell of claim 1, wherein, The first tab further includes an insulating layer, and the insulating layer includes a first insulating part and a second insulating part connected with the first insulating part; The edge region of the side of the main body where the plurality of first tabs and the protrusions are provided is a first region, and the root region of the first tab adjacent to the main body is a second region; The first insulating part is provided in the first region, and the second insulating part is provided on the second region and covers at least part of the protrusion.

3. The battery cell of claim 2, wherein, The protrusion includes a first surface and a second surface arranged opposite to each other along the thickness direction of the protrusion; the thickness direction of the protrusion is perpendicular to the winding axis direction of the electrode assembly; The ratio of the area of the first surface covered by the second insulating part to the area of the first surface is 0.8 to 1; and / or The ratio of the area of the second surface covered by the second insulating part to the area of the second surface is 0.8 to 1.

4. The battery cell of claim 2, wherein, The ratio of the surface area of the region covered by the second insulating part to the surface area of the protrusion is 0.8 to 1.

5. The battery cell according to any one of claims 1 to 4, characterized in that, The ratio of the size of the protrusion along the winding direction of the electrode assembly to the size of the protrusion along the winding axis direction of the electrode assembly is greater than or equal to 7.

6. The battery cell of any one of claims 1-4, wherein, The normal projection of any protrusion in all the protrusions on the reference surface has an overlapping part with the normal projection of any first tab in the plurality of first tabs on the reference surface; and / or The number of circle segments of the main body is M, and the number of circle segments provided with the protrusions is N; wherein 0.5≤N / M≤1, and N and M are positive integers.

7. The battery cell of any one of claims 1-4, wherein, At least one of the intermediate circle segments of the main body is provided with the protrusion.

8. The battery cell of claim 7, wherein, Each of the plurality of intermediate circle segments is provided with the protrusion.

9. The battery cell of claim 7, wherein, Along the winding direction of the electrode assembly, the same number of first tabs is arranged between every two adjacent protrusions.

10. The battery cell of any one of claims 1-4, wherein, The convex portion is orthographically projected on a plane perpendicular to the thickness direction of the convex portion as a first projection, and the thickness direction of the convex portion is perpendicular to the winding axis direction of the electrode assembly; The shape of all the first projections includes at least one of a rectangle, a square, a rhombus, and a trapezoid.

11. The battery cell of any one of claims 1-4, wherein, In the winding direction of the electrode assembly, the size of the convex portion in the winding axis direction of the electrode assembly changes in a first regularity; The first regularity includes one of no change, first decreasing and then increasing, first increasing and then decreasing, first decreasing and then increasing and then decreasing, and first increasing and then decreasing and then increasing.

12. The battery cell of any one of claims 1-4, wherein, In the winding axis direction of the electrode assembly, the size of the convex portion in the winding direction of the electrode assembly changes in a second regularity; The second regularity includes one of no change, decreasing, increasing, first decreasing and then increasing, first increasing and then decreasing, first decreasing and then increasing and then decreasing, and first increasing and then decreasing and then increasing.

13. The battery cell of any one of claims 1-4, wherein, The size of the convex portion in the winding axis direction of the electrode assembly is 2 mm to 6 mm; and / or The size of the convex portion in the winding direction of the electrode assembly is 5 mm to 9 mm.

14. The battery cell of any one of claims 1-4, wherein, The first tab is a positive electrode tab, and the second tab is a negative electrode tab.

15. A method of manufacturing a battery cell, characterized by, Comprise: A first tab, a second tab, and a separator are provided; the first tab comprises a main body portion, a plurality of first tabs, and a convex portion respectively provided at the first and last circle segments of the main body portion; in the width direction of the first tab, the plurality of first tabs and all the convex portions are provided on the same side of the main body portion, and the stiffness of the convex portion is greater than that of the first tab; The separator, the first tab, and the second tab are laminated and wound to form an electrode assembly; in the winding axis direction of the electrode assembly, the size of the convex portion is smaller than that of the first tab; in the winding direction of the electrode assembly, the size of the convex portion is smaller than that of the first tab; the electrode assembly has a reference surface, and the winding axis of the electrode assembly is located on the reference surface; The reference surface has oppositely arranged first and second sides, and the plurality of first tabs are located on the first side, and all the convex portions are located on the second side; The orthographic projection of all the convex portions on the reference surface has an overlapping portion with the orthographic projection of the plurality of first tabs on the reference surface; In the case where the in-winding alignment and the winding alignment of the first tab and the second tab both meet the alignment qualification condition, the electrode assembly is loaded into the accommodating cavity of the shell to form a battery monomer; wherein the in-winding alignment is determined based on the convex portion located at the first circle segment of the main body portion, and the winding alignment is determined based on the convex portion located at the last circle segment of the main body portion.

16. The method of claim 15, wherein The method for manufacturing the battery monomer further comprises: Before the first tab is wound in, a first image of the convex portion located at the first circle segment of the main body portion and the main body portion is obtained; and based on the first image, a first distance between the convex portion located at the first circle segment of the main body portion and the main body portion in the width direction of the first tab is determined. acquire a second image of the protrusion located at the first winding section of the main body portion and the main body portion after the first tab is wound into the winding piece; and determine a second distance between the protrusion located at the first winding section of the main body portion and the second tab in the width direction of the first tab according to the second image; determine whether the winding alignment meets an alignment qualification condition based on a difference between the first distance and the second distance.

17. The method of claim 15, wherein The method for manufacturing the battery cell further includes: acquire a third image of the protrusion located at the last winding section of the main body portion and the main body portion before the last winding section of the main body portion is wound into the winding piece; and determine a third distance between the protrusion located at the last winding section of the main body portion and the main body portion in the width direction of the first tab according to the third image; acquire a fourth image of the protrusion located at the last winding section of the main body portion and the main body portion after the last winding section of the main body portion is wound into the winding piece; and determine a fourth distance between the protrusion located at the first winding section of the main body portion and the second tab in the width direction of the first tab according to the fourth image; determine whether the winding alignment meets an alignment qualification condition based on a difference between the third distance and the fourth distance.

18. The method of claim 15, 16 or 17, wherein the method further comprises: The protrusion is located on the middle winding section of the main body portion. The method for manufacturing the battery cell further includes: verify a reference alignment of the middle winding sections of the first tab and the second tab based on a verification alignment of the middle winding sections of the first tab and the second tab; wherein the reference alignment is determined based on the first tab ear located on the middle winding section of the main body portion, and the verification alignment is determined based on the protrusion located on the middle winding section of the main body portion; in a case where the winding alignment and the winding alignment both meet the alignment qualification condition, and the reference alignment meets a verification qualification condition, assemble the electrode assembly into a receiving cavity of an outer shell to form the battery cell.

19. The method of claim 15, 16, or 17, wherein the method further comprises: The method for manufacturing the battery cell further includes: provide the first tab strip; die cut the first tab strip to form the plurality of first tab ears and all the protrusions to obtain the first tab.

20. The method of claim 15, 16, or 17, wherein the method further comprises: The method for manufacturing the battery cell further includes: when the first tab is wound at the feeding end of the first tab, provide an acting force acting on the feeding end of the first tab away from one side of the winding piece, so that the feeding end of the first tab can be close to the winding piece.

21. A battery device, characterized by The battery cell includes any one of the battery cells according to claims 1-14; or the battery cell is manufactured by the method for manufacturing the battery cell according to any one of claims 15-20.

22. An electrical device, comprising: The battery device includes the battery device according to claim 21.

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