Electrode assembly, battery device and electric equipment

Abstract

The invention discloses an electrode assembly, a battery device and electric equipment, and relates to the technical field of batteries, the battery device comprises a battery monomer, the battery monomer comprises a shell and an electrode assembly arranged in the shell, the electrode assembly comprises a positive tab and a negative tab, the positive tab comprises a plurality of first tab pieces, and the negative tab comprises a plurality of second tab pieces; the side edges of the positive plates of different layers extend to form a plurality of first tab pieces, the negative tab comprises a plurality of second tab pieces, and the side edges of the negative plates of different layers extend to form a plurality of second tab pieces; the plurality of first tab pieces form N first tab clusters, the plurality of second tab pieces form M second tab clusters, any first tab cluster and any second tab cluster are arranged at intervals, the projection edges of any two adjacent first tab clusters in the N first tab clusters in the thickness direction of the electrode assembly are in contact, and the projection edges of any two adjacent second tab clusters in the N second tab clusters in the thickness direction of the electrode assembly are in contact. And the projection edges of any two adjacent second tab clusters in the M second tab clusters in the thickness direction of the electrode assembly are in contact with each other. According to the battery monomer, the space for bending the tabs can be reduced, and the energy density can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to an electrode assembly, a battery device and an electrical equipment. Background Art

[0002] As the demand for battery performance increases, higher requirements are also placed on battery resistance. In the battery cell structure, the solution of one electrode and one tab can effectively reduce the internal resistance of the battery cell, but due to the large number of tab layers, the tabs are difficult to close tightly, resulting in the need for a higher tab folding space, which greatly reduces the energy density of the battery cell. Summary of the invention

[0003] The main purpose of the present invention is to provide a battery device, aiming to solve the technical problem that the multi-layer tabs in the battery device are difficult to close tightly.

[0004] To achieve the above object, the battery device provided by the present invention includes a battery cell, wherein the battery cell includes a housing and an electrode assembly disposed in the housing, wherein the electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a spacer disposed therebetween; The electrode assembly further includes a positive electrode tab and a negative electrode tab, wherein the positive electrode tab includes a plurality of first electrode tab sheets, and the plurality of first electrode tab sheets are extended from the sides of the positive electrode sheets of different layers, and the negative electrode tab includes a plurality of second electrode tab sheets, and the plurality of second electrode tab sheets are extended from the sides of the negative electrode sheets of different layers; Wherein, the plurality of first electrode tab sheets form N first electrode tab clusters, the N first electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each of the first electrode tab clusters is composed of 1 / N of the plurality of first electrode tab sheets, wherein N is a positive integer, and N is greater than or equal to 2; The plurality of second electrode tab sheets form M second electrode tab clusters, the M second electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each second electrode tab cluster is composed of 1 / M of the plurality of second electrode tab sheets, wherein M is a positive integer, and M is greater than or equal to 2; Any first electrode tab cluster is spaced apart from any second electrode tab cluster, and any two adjacent ones of the N first electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact, and any two adjacent ones of the M second electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact.

[0005] In this example, the battery device may include one battery cell or multiple battery cells, and the electrode assembly in the battery cell is formed by stacking and processing the positive electrode sheet, the negative electrode sheet and the spacer in sequence, and may be a winding structure or a laminated structure. The positive electrode tab of the electrode assembly includes multiple first electrode tab sheets, for example, each layer is provided with a first electrode tab sheet, and the negative electrode tab includes multiple second electrode tab sheets, for example, each layer is provided with a second electrode tab sheet.

[0006] The plurality of first pole tabs are divided into N first pole tab clusters, and the number of first pole tabs in each first pole tab cluster is the same and is 1 / N, so that the heights of the N first pole tab clusters after bending can be made equal, thereby minimizing the occupied space to the greatest extent and further improving the energy density. The number of first pole tabs that are not overlapped can be increased, and as the value of N increases, the bending space can be further reduced.

[0007] The plurality of second pole tabs are divided into M second pole tab clusters, and the number of second pole tabs in each second pole tab cluster is the same and is 1 / M, so that the heights of the M second pole tab clusters after bending can be made equal, thereby minimizing the occupied space to the greatest extent and further improving the energy density. And as the value of M increases, the number of second pole tabs that are not overlapped can be increased, which can further reduce the bending space, increase the welding area, and further improve the round-trip efficiency.

[0008] In the above structure, the number of stacked layers of the first and / or second pole tabs in the same column in the thickness direction is reduced, so that the multiple first and / or second pole tabs can be effectively closed, which facilitates the bending of the pole tabs and reduces the space required for bending the pole tabs, thereby improving the energy density of the battery cell; and the thickness of each column of the bent positive and negative pole tabs is reduced, which is also conducive to improving the pole tab welding yield. At the same time, the positive and negative pole tabs of this structure can also increase the ultrasonic welding area, reduce impedance, and thus improve the round-trip efficiency.

[0009] A plurality of first pole lug sheets form N first pole lug clusters, and a plurality of second pole lug sheets form M second pole lug clusters, and the projected edges of any two adjacent first pole lug clusters are brought into contact with each other, and the projected edges of any two adjacent second pole lug clusters are brought into contact with each other, that is, the N first pole lug clusters are arranged closely in a straight line, and the M second pole lug clusters are arranged closely in a straight line, and the first pole lug clusters and the second pole lug clusters are arranged at intervals, so as to avoid short circuits, maximize the use of the space of the electrode assembly in the length direction, further increase the number of non-overlapping pole lug clusters, reduce the height of each pole lug cluster, and improve the performance of the battery cell; and make welding as convenient as possible, so that the plurality of first pole lug clusters can be conveniently connected to the positive electrode terminal or the adapter structure, and the plurality of second pole lug clusters can be conveniently connected to the negative electrode terminal or the adapter structure.

[0010] In one embodiment of the present invention, the lateral dimension of the projection of the N first pole lug clusters in the thickness direction of the electrode assembly is S1, the lateral dimension of the projection of the M second pole lug clusters in the thickness direction of the electrode assembly is S2, the lateral spacing dimension between the first pole lug cluster and the second pole lug cluster with the closest lateral distance in the projection in the thickness direction of the electrode assembly is S3, and the length of the electrode assembly is L, wherein L=S1+S2+S3.

[0011] In this example, by setting the values ​​of N and M, the sum of the lateral dimensions occupied by the N first pole lug clusters and the M second pole lug clusters and the nearest spacing dimensions therebetween is equal to the lateral length of the electrode assembly, thereby maximizing the use of the space in the length direction of the electrode assembly and minimizing the bending height of each first pole lug cluster and each second pole lug cluster, thereby further improving the energy density.

[0012] In one embodiment of the present invention, at least two electrode assemblies are provided, and at least two electrode assemblies are arranged side by side in the shell along the thickness direction of the electrode assembly; At least two of the positive electrode tabs in the paired electrode assemblies are arranged non-overlappingly in the thickness direction of the electrode assembly; and / or at least two of the negative electrode tabs in the paired electrode assemblies are arranged non-overlappingly in the thickness direction of the electrode assembly.

[0013] In this example, when there are at least two electrode assemblies, for example, two or three, at least two adjacent electrode assemblies need to be paired, at least two of the positive pole ears and / or negative pole ears of the two paired electrode assemblies are arranged non-overlappingly in the thickness direction, thereby reducing the height of the paired pole ears in the two electrode assemblies after stacking and bending, further facilitating bending and welding, reducing the occupied space, and improving energy density.

[0014] In one embodiment of the present invention, at least two of the positive electrode ears in the paired electrode assembly are arranged with their projected edges in the thickness direction of the electrode assembly in contact with each other; and / or, at least two of the negative electrode ears in the paired electrode assembly are arranged with their projected edges in the thickness direction of the electrode assembly in contact with each other.

[0015] In this example, the positive and / or negative tabs that need to be paired can be made more compact, thereby facilitating welding connection, and can also save more space for the structure in which the positive tab is divided into multiple tab clusters and the structure in which the negative tab is divided into multiple tab clusters.

[0016] In one embodiment of the present invention, the battery cell further includes a first adapter plate and a second adapter plate, the first adapter plate includes a pole connecting portion and a first adapter portion connected to each other, the first adapter portion correspondingly electrically connecting N first pole lug clusters; the second adapter plate includes a pole connecting portion and a second adapter portion connected to each other, the second adapter portion correspondingly electrically connecting M second pole lug clusters.

[0017] In this example, the first adapter plate and the second adapter plate can be designed to achieve electrical connection between the positive electrode ear and the positive electrode column, and electrical connection between the negative electrode ear and the negative electrode column, thereby increasing the welding area, effectively reducing the internal resistance, and improving the round-trip efficiency.

[0018] In one embodiment of the present invention, the battery cell further comprises two flanges, wherein one flange is electrically connected to N first electrode tab clusters, and the other flange is electrically connected to M second electrode tab clusters.

[0019] In this example, one flange can simultaneously connect multiple pole lug clusters of the positive pole lug, and another flange can connect multiple pole lug clusters of the negative pole lug. The other surface of the flange is electrically connected to the pole. Through the large-area structure of the flange, the internal resistance is further reduced and the round-trip efficiency is improved.

[0020] The present invention also provides an electrode assembly, the electrode assembly comprising a positive electrode sheet, a negative electrode sheet and a separator disposed therebetween; The electrode assembly further includes a positive electrode tab and a negative electrode tab, wherein the positive electrode tab includes a plurality of first electrode tab sheets, and the plurality of first electrode tab sheets are extended from the sides of the positive electrode sheets of different layers, and the negative electrode tab includes a plurality of second electrode tab sheets, and the plurality of second electrode tab sheets are extended from the sides of the negative electrode sheets of different layers; Wherein, the plurality of first electrode tab sheets form N first electrode tab clusters, the N first electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each of the first electrode tab clusters is composed of 1 / N of the plurality of first electrode tab sheets, wherein N is a positive integer, and N is greater than or equal to 2; The plurality of second electrode tab sheets form M second electrode tab clusters, the M second electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each second electrode tab cluster is composed of 1 / M of the plurality of second electrode tab sheets, wherein N is a positive integer, and M is greater than or equal to 2; Any first electrode tab cluster is spaced apart from any second electrode tab cluster, and any two adjacent ones of the N first electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact, and any two adjacent ones of the M second electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact.

[0021] In this example, when a plurality of first pole tabs are bent to form a positive pole tab, two non-overlapping first pole tabs are bent into a row, and when a plurality of second pole tabs are bent to form a negative pole tab, two non-overlapping second pole tabs are bent into a row, so as to reduce the number of stacked layers of the first pole tab and / or the second pole tab in the same row in the thickness direction, so that the plurality of first pole tabs and / or the second pole tab can be effectively closed, convenient for bending the pole tabs, and reduce the space required for bending the pole tabs, thereby improving the energy density of the battery cell; and the thickness of each column of the positive pole tab and the negative pole tab after bending is thinned, which is also conducive to improving the pole tab welding yield. At the same time, the positive pole tab and the negative pole tab of this structure can also increase the ultrasonic welding area, reduce the impedance, and thus improve the round-trip efficiency. At the same time, the height of the N first pole tab clusters and / or the M second pole tab clusters after bending can be made equivalent, so as to minimize the occupied space and further improve the energy density, and as the values ​​of N and / or M are larger, the bending space can be further reduced.

[0022] The projected edges of any two adjacent first pole lug clusters are brought into contact, and the projected edges of any two adjacent second pole lug clusters are brought into contact, that is, N first pole lug clusters are arranged closely in a straight line, and M second pole lug clusters are arranged closely in a straight line, and the first pole lug clusters and the second pole lug clusters are arranged at intervals, so as to avoid short circuits, maximize the use of the space of the electrode assembly in the length direction, further increase the number of non-overlapping pole lug clusters, reduce the height of each pole lug cluster, and improve the performance of the battery cell; and make welding as convenient as possible, so that multiple first pole lug clusters can be conveniently connected to the positive electrode terminal or the adapter structure, and multiple second pole lug clusters can be conveniently connected to the negative electrode terminal or the adapter structure.

[0023] In one embodiment of the present invention, the electrode assembly is a wound structure; Protection of wound battery cells.

[0024] The present invention also provides an electrical device, comprising the battery device as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0026] Figure 1 It is a structural schematic diagram of the electrical equipment of the present invention; Figure 2 A partial exploded view of the battery device of the present invention; Figure 3It is a schematic diagram of the explosion structure of a battery cell in a battery device of the present invention; Figure 4 The structure of another embodiment of the electrode assembly of the battery cell in the battery device of the present invention is schematically shown; Figure 5 It is a schematic diagram of the explosion structure of another embodiment of a battery cell in the battery device of the present invention; Figure 6 FIG. 1 is an exploded schematic diagram of another embodiment of a battery cell in a battery device of the present invention.

[0027] Description of Figure Numbers: 100, battery device; 10, housing; 11, first part; 12, second part; 20, battery cell; 21, housing; 211, shell; 212, end cover; 22, electrode assembly; 221, positive electrode ear; 2211, first electrode ear cluster; 222, negative electrode ear; 2221, second electrode ear cluster; 23, first adapter; 231, first adapter part; 24, second adapter; 241, second adapter part; 25, flange; 200, controller; 300, motor.

[0028] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text is to include three parallel solutions. Taking "A and / or B as an example", it includes solution A, or solution B, or a solution that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] The battery devices mentioned in the art can be divided into disposable batteries and rechargeable batteries according to whether they are rechargeable. The common types of rechargeable batteries currently include: lead-acid batteries, nickel-metal hydride batteries and lithium-ion batteries. The battery device described in the embodiments of the present invention refers to a rechargeable battery. The embodiments disclosed in the present invention will be described below mainly using lithium-ion batteries as an example. It should be understood that the embodiments disclosed in the present invention are applicable to any other appropriate type of rechargeable battery. The battery device mentioned in the embodiments disclosed in the present invention can be directly or indirectly applied to an appropriate device to power the device.

[0034] The battery device mentioned in the embodiments disclosed in the present invention refers to a single physical module including one or more battery cells to provide a predetermined voltage and capacity, which can be a battery module or a battery pack. The battery cell is the basic unit in the battery device and can be used to make a battery module or a battery pack. The battery module is formed by connecting a certain number of battery cells in series and / or in parallel and placing them in a frame in order to protect the battery cells from external impact, heat, vibration, etc. The battery pack generally includes a battery module, a battery management system, and a box that accommodates the battery module and the battery management system.

[0035] The electrode assembly is an important component of the battery cell. According to the preparation method of the electrode assembly, it can be divided into a wound electrode assembly and a laminated electrode assembly. In a wound electrode assembly, the positive electrode sheet, the separator, and the negative electrode sheet are stacked in sequence and wound more than two times. In a laminated electrode assembly, multiple positive electrode sheets and multiple negative electrode sheets are alternately stacked. Among them, the wound electrode assembly is widely used because it is relatively simple to operate and the quality is easy to control. The wound electrode assembly can be a square structure or a cylindrical structure. Among them, the square wound electrode assembly is widely used due to its advantages such as good heat dissipation.

[0036] Battery cells mainly rely on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive current collector and a positive active material layer, and the positive active material layer is coated on the surface of the positive current collector; the positive current collector includes a positive current collector and a positive electrode tab connected to the positive current collector, the positive current collector is coated with a positive active material layer, and the positive electrode tab is not coated with the positive active material layer. Taking lithium-ion batteries as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, and the negative active material layer is coated on the surface of the negative current collector; the negative current collector includes a negative current collector and a negative electrode tab connected to the negative current collector, the negative current collector is coated with a negative active material layer, and the negative electrode tab is not coated with a negative active material layer. The negative electrode current collector may be made of copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon or silicon, etc. The separator may be made of PP (polypropylene) or PE (polyethylene), etc.

[0037] The electrode assembly draws out the current through the positive and negative tabs. In order to ensure that a large current can pass without melting, the positive tabs are multiple and stacked together, and connected to the electrode terminals or adapter components of the battery cell. The negative tabs are multiple and stacked together, and connected to the electrode terminals or adapter components of the battery cell. In this way, the more tabs there are, the greater the total thickness of the tabs, and the tabs are difficult to close tightly, resulting in a higher folding space for the tabs, which greatly reduces the energy density of the battery cell. At the same time, when the total thickness of the tabs reaches a certain value, it may cause poor connection between the tabs and the poles, or even cause the tabs and the poles to be unable to connect.

[0038] Based on the above background, the present invention proposes a battery device, which improves the electrode assembly of a battery cell in the battery device so that at least two of the multiple first pole lug sheets are not overlapped in the thickness direction of the electrode assembly, and / or at least two of the multiple second pole lug sheets are not overlapped in the thickness direction of the electrode assembly, thereby reducing the number of stacking layers of the first pole lug sheets and / or the second pole lug sheets in the same thickness direction, so that the multiple first pole lug sheets and / or the second pole lug sheets can be effectively closed, facilitating the bending of the pole lugs and reducing the space required for bending the pole lugs, thereby improving the energy density of the battery cell.

[0039] The battery device disclosed in the embodiment of the present application can be used in various energy storage systems that use batteries as power sources or use batteries as energy storage elements. The electrical equipment can be, but is not limited to, mobile phones, tablets, laptops, electric toys, electric tools, battery cars, electric cars, ships, spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0040] For the convenience of explanation, the following examples are referred to Figure 1 , an electrical device in one embodiment of the present application is taken as an example of a vehicle.

[0041] Figure 1 The electrical equipment provided for some embodiments of the present application is a schematic diagram of the structure of a vehicle. The vehicle may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle, and the battery device 100 may be provided at the bottom, head or tail of the vehicle. The battery device 100 may be used to power the vehicle, for example, the battery device 100 may be used as an operating power source for the vehicle. The vehicle may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and driving the vehicle.

[0042] In some embodiments of the present application, the battery device 100 can be used not only as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0043] refer to Figure 2 , Figure 2An exploded view of a battery device 100 provided in some embodiments of the present application. The battery device 100 includes a box 10 and at least two battery cells 20, wherein the box 10 is used to provide a storage space for the battery cells 20, and the box 10 can adopt a variety of structures. In some embodiments, the box 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space. The second part 12 may be a hollow structure with one end open, the first part 11 may be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 may also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0044] In the battery device 100, there may be a plurality of battery cells 20, which may be connected in series, in parallel, or in mixed series to form a whole and accommodated in the box 10. Mixed series means that the plurality of battery cells 20 are both connected in series and in parallel. The battery device 100 may also include other structures, for example, a busbar component for realizing electrical connection between the plurality of battery cells 20.

[0045] The battery cell 20 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, etc. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0046] In some cases, the battery cell 20 can also be directly installed in the vehicle without the box body 10 , that is, there is no need to form a battery pack, and the structure of the vehicle body itself serves as a fixing structure for the battery cell 20 .

[0047] The battery device 100 of the present application is described below with reference to a specific embodiment: Please refer to Figure 3 to Figure 4 In one embodiment of the present invention, the battery device 100 includes a battery cell 20, wherein the battery cell 20 includes a housing 21 and an electrode assembly 22 disposed in the housing 21, wherein the electrode assembly 22 includes a positive electrode sheet, a negative electrode sheet, and a spacer disposed therebetween; The electrode assembly 22 further includes a positive electrode tab 221 and a negative electrode tab 222. The positive electrode tab 221 includes a plurality of first electrode tab sheets, and the plurality of first electrode tab sheets are extended from the sides of the positive electrode sheets of different layers. The negative electrode tab 222 includes a plurality of second electrode tab sheets, and the plurality of second electrode tab sheets are extended from the sides of the negative electrode sheets of different layers. Wherein, the plurality of first electrode tab sheets form N first electrode tab clusters 2211, the N first electrode tab clusters 2211 are arranged non-overlappingly in the thickness direction of the electrode assembly 22, and each of the first electrode tab clusters 2211 is composed of 1 / N of the plurality of first electrode tab sheets, wherein N is a positive integer, and N is greater than or equal to 2; The plurality of second electrode tab sheets form M second electrode tab clusters 2221, the M second electrode tab clusters 2221 are arranged non-overlappingly in the thickness direction of the electrode assembly 22, and each second electrode tab cluster 2221 is composed of 1 / M of the plurality of second electrode tab sheets, wherein M is a positive integer, and M is greater than or equal to 2; Any first pole lug cluster 2211 is spaced apart from any second pole lug cluster 2221, and any two adjacent ones of the N first pole lug clusters 2211 have projected edges in the thickness direction of the electrode assembly 22 in contact with each other, and any two adjacent ones of the M second pole lug clusters 2221 have projected edges in the thickness direction of the electrode assembly 22 in contact with each other.

[0048] In this example, the battery device 100 may include one battery cell 20 or multiple battery cells 20, which are not limited here. The battery cell 20 includes a shell 21 and an electrode assembly 22 disposed in the shell 21. The shell 21 includes a shell body 211 and an end cover 212. The shell body 211 forms a cavity with an opening, and the end cover 212 covers the opening of the cavity. The electrode assembly 22 is formed by stacking and processing the positive electrode sheet, the negative electrode sheet and the spacer in sequence, and can be a winding structure or a laminated structure, which is not limited here.

[0049] Specifically, the electrode assembly 22 includes a positive electrode ear 221 and a negative electrode ear 222. The positive electrode ear 221 is used to electrically connect to the positive electrode terminal or the transition member of the end cover 212, and the negative electrode ear 222 is used to electrically connect to the negative electrode terminal or the transition member of the end cover 212. The positive electrode ear 221 of the electrode assembly 22 includes a plurality of first electrode ear sheets, and the sides of the positive electrode sheets of different layers are extended with a plurality of first electrode ear sheets. It can be that each layer of the positive electrode sheets is extended with a first electrode ear sheet, so that the internal resistance is effectively reduced; of course, it can also be that one first electrode ear sheet is extended for each positive electrode sheet with one or more layers, which is not limited here. The negative electrode ear 222 includes a plurality of second electrode ear sheets, and the sides of the negative electrode sheets of different layers are extended with a plurality of second electrode ear sheets, that is, each layer of the negative electrode sheets is provided with a second electrode ear sheet, which effectively reduces the internal resistance. Of course, it can also be that one second electrode ear sheet is extended for each negative electrode sheet with one or more layers, which is not limited here.

[0050] It can be understood that the thickness direction of the electrode assembly 22 is the extension direction of its smallest size. For example, when the electrode assembly 22 is a winding structure, it has a winding direction and a height direction extending along the winding axis. When the winding structure is hot-pressed to form a square electrode assembly 22, the hot-pressing direction is the thickness direction. When the electrode assembly 22 is a laminated structure, the stacking direction of the pole pieces is the thickness direction of the electrode assembly 22. The bending direction of the first pole tab and the second pole tab here is not limited. For example, the pole tab located near the middle of the electrode assembly 22 in the thickness direction can be bent toward any side of the large surface of the electrode assembly 22, but the pole tab located on the outer ring of the electrode assembly 22 needs to be bent toward the middle of the thickness direction. In this way, the pole tab can be bent and located at the end face of the pole piece without exceeding the surface of the electrode assembly 22.

[0051] The multiple first pole lug sheets are divided into N first pole lug clusters 2211, where the first pole lug cluster 2211 refers to the structural state formed by bending the overlapping first pole lug sheets, wherein N is greater than or equal to 2. For example, when N is 2, the multiple first pole lug sheets are divided into two first pole lug clusters 2211, which means that the number of first pole lug sheets in one of the first pole lug clusters 2211 is 1, and the number of first pole lug sheets in the other first pole lug cluster 2211 is N-1, or the number of first pole lug sheets in one of the first pole lug clusters 2211 is 2, and the number of first pole lug sheets in the other first pole lug cluster 2211 is N-2.

[0052] When the number of first pole tabs of each first pole tab cluster 2211 is the same and is 1 / N, the heights of the N first pole tab clusters 2211 after bending can be made equal. For example, when N is 2, the number of first pole tabs in each first pole tab cluster 2211 is 1 / 2 of the total number, so that the overall height after bending is equal and the height is the smallest when there are two rows of first pole tab clusters 2211, thereby minimizing the occupied space and further improving the energy density. And as the value of N increases, the number of first pole tabs that are not overlapped increases, which can further reduce the bending space. For example, when N is 3, that is, at least 3 first pole tabs are not overlapped after bending in the thickness direction, forming 3 first pole tab clusters 2211, and the number of first pole tabs in each first pole tab cluster 2211 is 1 / 3 of the total number, further reducing the height of the first pole tab cluster 2211 after bending, and further improving the energy density.

[0053] The plurality of second tab sheets are divided into M second tab clusters 2221, wherein the second tab cluster 2221 refers to the structure formed by bending the overlapping second tab sheets, wherein M is greater than or equal to 2, and the specific configuration can refer to the configuration of the first tab cluster 2211.

[0054] When the number of second pole tabs of each second pole tab cluster 2221 is the same and 1 / M, the heights of the M second pole tab clusters 2221 after bending can be made equal, thereby minimizing the occupied space and further improving the energy density. As the value of M increases, the number of second pole tabs that are not overlapped can be increased, which can further reduce the bending space, increase the welding area, and further improve the round-trip efficiency.

[0055] A plurality of first pole lug sheets form N first pole lug clusters 2211, and a plurality of second pole lug sheets form M second pole lug clusters 2221. On the basis of the above embodiments, the number of pole lug sheets that are overlapped and bent can be further reduced, thereby further reducing the space occupied by the bending of the pole lugs, further improving the energy density, and facilitating welding connections.

[0056] Any first electrode tab cluster 2211 and any second electrode tab cluster 2221 are spaced apart from each other, which means that the first electrode tab cluster 2211 and the second electrode tab cluster 2221 are spaced apart from each other in a length direction perpendicular to the thickness direction, that is, they are not in contact with each other, thereby avoiding short circuit. The projected edges of any two adjacent first pole lug clusters 2211 are brought into contact, and the projected edges of any two adjacent second pole lug clusters 2221 are brought into contact, that is, the projections of the N first pole lug clusters 2211 in the thickness direction are arranged closely in a straight line, and the projections of the two adjacent first pole lug clusters 2211 facing each other in the thickness direction are abutted; the projections of the M second pole lug clusters 2221 in the thickness direction are arranged closely in a straight line, and the projections of the two adjacent second pole lug clusters 2221 facing each other in the thickness direction are abutted, which can maximize the use of the space of the electrode assembly 22 in the length direction, further increase the number of non-overlapping pole lug clusters, reduce the height of each pole lug cluster, and improve the performance of the battery cell 20; and make welding as convenient as possible, so that multiple first pole lug clusters 2211 are conveniently connected to the positive electrode terminal or the adapter structure, and multiple second pole lug clusters 2221 are conveniently connected to the negative electrode terminal or the adapter structure.

[0057] In other examples, at least two of the plurality of first pole tabs may be arranged non-overlappingly in the thickness direction of the electrode assembly 22, that is, after the plurality of first pole tabs are bent in the thickness direction, at least two of them are arranged non-overlappingly, for example, two of them are arranged non-overlappingly, or three or more of them are arranged non-overlappingly. Alternatively, at least two of the plurality of second pole tabs may be arranged non-overlappingly in the thickness direction of the electrode assembly 22, which means that after the plurality of second pole tabs are bent in the thickness direction, at least two of them are arranged non-overlappingly, for example, two of them are arranged non-overlappingly or three of them are arranged non-overlappingly; or, after the plurality of first pole tabs and the plurality of second pole tabs are bent in the thickness direction, at least two of them are arranged non-overlappingly.

[0058] In this way, when a plurality of first pole tabs are bent to form a positive pole tab 221, two non-overlapping first pole tabs are bent into a row, and when a plurality of second pole tabs are bent to form a negative pole tab 222, two non-overlapping second pole tabs are bent into a row, so as to reduce the number of stacked layers of the first pole tabs and / or the second pole tabs in the same row in the thickness direction, so that the plurality of first pole tabs and / or the second pole tabs can be effectively closed, the bending of the pole tabs is convenient, and the space required for bending the pole tabs is reduced, thereby improving the energy density of the battery cell 20; and the thickness of each row of the bent positive pole tabs 221 and the negative pole tabs 222 is thinned, which is also conducive to improving the pole tab welding yield. At the same time, the positive pole tabs 221 and the negative pole tabs 222 of this structure can also increase the ultrasonic welding area, reduce the impedance, and thus improve the round-trip efficiency.

[0059] Please continue to refer to Figure 4 In one embodiment of the present invention, the lateral dimension of the projection of the N first pole lug clusters 2211 in the thickness direction of the electrode assembly 22 is S1, the lateral dimension of the projection of the M second pole lug clusters 2221 in the thickness direction of the electrode assembly 22 is S2, the lateral spacing dimension between the first pole lug cluster 2211 and the second pole lug cluster 2221 with the closest lateral distance in the projection in the thickness direction of the electrode assembly 22 is S3, and the length of the electrode assembly 22 is L, wherein L=S1+S2+S3.

[0060] In this example, the lateral length refers to the dimension along the length direction of the electrode assembly 22. When the lateral dimension of each first electrode ear cluster 2211 in the length direction of the electrode assembly 22 is x, S1 is equal to N*x. Similarly, when the lateral dimension of each second electrode ear cluster 2221 in the length direction of the electrode assembly 22 is y, S2 is equal to M*y. Here, N first electrode ear clusters 2211 are arranged side by side at one end of the electrode assembly 22 in the length direction, and M second electrode ear clusters 2221 are arranged side by side at the other end of the electrode assembly 22 in the length direction, the lateral spacing dimension between the closest first electrode ear cluster 2211 and the second electrode ear cluster 2221 is S3.

[0061] By setting the values ​​of N and M, the sum of the lateral dimensions occupied by the N first pole lug clusters 2211 and the M second pole lug clusters 2221 and the nearest spacing dimensions therebetween is equal to the lateral length of the electrode assembly 22, thereby maximizing the use of the space in the length direction of the electrode assembly 22 and minimizing the bending height of each first pole lug cluster 2211 and each second pole lug cluster 2221, thereby further improving the energy density.

[0062] Please refer to Figure 5 In one embodiment of the present invention, at least two electrode assemblies 22 are provided, and at least two electrode assemblies 22 are arranged side by side in the shell 21 along the thickness direction of the electrode assembly 22; At least two of the positive tabs 221 in the paired electrode assembly 22 are arranged non-overlappingly in the thickness direction of the electrode assembly 22; and / or, at least two of the negative tabs 222 in the paired electrode assembly 22 are arranged non-overlappingly in the thickness direction of the electrode assembly 22.

[0063] In this example, when there are at least two electrode assemblies 22, for example, two or three. At least two electrode assemblies 22 are arranged side by side in the shell 21 along the thickness direction of the electrode assembly 22, which means that at least two electrode assemblies 22 are arranged with their large surfaces facing each other and arranged in the thickness direction of the electrode assembly 22. Among them, at least two electrode assemblies 22 need to be paired, which can be two adjacent electrode assemblies 22 paired, or three consecutive adjacent electrode assemblies 22 paired, and at least two of the positive tabs 221 and / or negative tabs 222 of the paired electrode assemblies 22 are arranged non-overlappingly in the thickness direction, which means that when there are two positive tabs 221, the two positive tabs 221 are arranged non-overlappingly, and when there are three or more positive tabs 221, it is set that at least two positive tabs 221 are arranged non-overlappingly in the thickness direction. The arrangement of the negative tab 222 is the same as the above-mentioned positive tab 221.

[0064] This structure can reduce the height of the paired tab stacks in the two electrode assemblies 22 after bending, further facilitates bending and welding, reduces occupied space, and improves energy density.

[0065] In one embodiment of the present invention, at least two of the positive electrode ears 221 in the paired electrode assembly 22 are arranged with their projected edges in the thickness direction of the electrode assembly 22 in contact with each other; and / or, at least two of the negative electrode ears 222 in the paired electrode assembly 22 are arranged with their projected edges in the thickness direction of the electrode assembly 22 in contact with each other.

[0066] In this example, the projected edges of the paired positive electrode ear 221 in the thickness direction of the electrode assembly 22 are abutted against each other, and the projected edges of the paired negative electrode ear 222 in the thickness direction of the electrode assembly 22 are abutted against each other. This can make the two positive electrode ears 221 and / or negative electrode ears 222 of the electrode assembly 22 to be paired more compact, thereby facilitating welding connection, and can also save more space for the structure in which the positive electrode ear 221 is divided into multiple electrode ear clusters and the structure in which the negative electrode ear 222 is divided into multiple electrode ear clusters.

[0067] Please refer to Figure 6In one embodiment of the present invention, the battery cell 20 further includes a first adapter plate 23 and a second adapter plate 24, the first adapter plate 23 includes a pole connecting portion and a first adapter portion 231 connected thereto, the first adapter portion 231 correspondingly electrically connecting N first pole lug clusters 2211; the second adapter plate 24 includes a pole connecting portion and a second adapter portion 241 connected thereto, the second adapter portion 241 correspondingly electrically connecting M second pole lug clusters 2221.

[0068] In this example, when there is one electrode assembly 22, the pole connection portion of the first adapter 23 is used to electrically connect the pole of the end cover 212, and the first adapter 231 is extended from one side of the pole connection portion in a direction perpendicular to the pole connection portion. The first adapter 231 is in a strip shape, which is convenient for simultaneous electrical connection with N first pole ear clusters 2211. When there are two electrode assemblies 22, two first adapters 231 are also provided, and each first adapter 231 corresponds to the N first pole ear clusters 2211 of an electrode assembly 22. By analogy, the electrode assembly 22 can also be 3 or more. Similarly, the structure of the second adapter 24 is designed with reference to the structure of the first adapter 23.

[0069] Through the design of the first adapter plate 23 and the second adapter plate 24, the positive electrode ear 221 is electrically connected to the positive electrode column, and the negative electrode ear 222 is electrically connected to the negative electrode column, thereby increasing the welding area, effectively reducing the internal resistance, and improving the round-trip efficiency.

[0070] Please refer again Figure 5 In one embodiment of the present invention, the battery cell 20 further includes two flanges 25 , wherein one flange 25 is electrically connected to N first electrode tab clusters 2211 , and the other flange 25 is electrically connected to M second electrode tab clusters 2221 .

[0071] In this example, the flange 25 is roughly in the shape of a flat plate, and its shape is a rectangular parallelepiped. One surface of a flange 25 can simultaneously correspond to multiple pole ear clusters connected to the positive pole ear 221, and one surface of another flange 25 is connected to multiple pole ear clusters of the negative pole ear 222. The other surface of the flange 25 is electrically connected to the pole. Through the large-area structure of the flange 25, the internal resistance is further reduced and the round-trip efficiency is improved.

[0072] Please refer to Figure 4 The present invention further provides an electrode assembly 22, wherein the electrode assembly 22 includes a positive electrode sheet, a negative electrode sheet, and a spacer disposed therebetween; The electrode assembly 22 further includes a positive electrode tab 221 and a negative electrode tab 222. The positive electrode tab 221 includes a plurality of first electrode tab sheets, and the sides of the positive electrode sheets of different layers are extended to form a plurality of the first electrode tab sheets. The negative electrode tab 222 includes a plurality of second electrode tab sheets, and the sides of the negative electrode sheets of different layers are extended to form a plurality of the second electrode tab sheets. Wherein, the plurality of first electrode tab sheets form N first electrode tab clusters 2211, the N first electrode tab clusters 2211 are arranged non-overlappingly in the thickness direction of the electrode assembly 22, and each of the first electrode tab clusters 2211 is composed of 1 / N of the plurality of first electrode tab sheets, wherein N is a positive integer, and N is greater than or equal to 2; The plurality of second electrode tab sheets form M second electrode tab clusters 2221, the M second electrode tab clusters 2221 are arranged non-overlappingly in the thickness direction of the electrode assembly 22, and each second electrode tab cluster 2221 is composed of 1 / M of the plurality of second electrode tab sheets, wherein N is a positive integer, and M is greater than or equal to 2; Any first pole lug cluster 2211 is spaced apart from any second pole lug cluster 2221, and any two adjacent ones of the N first pole lug clusters 2211 have projected edges in the thickness direction of the electrode assembly 22 in contact with each other, and any two adjacent ones of the M second pole lug clusters 2221 have projected edges in the thickness direction of the electrode assembly 22 in contact with each other.

[0073] In this example, when a plurality of first pole tabs are bent to form a positive pole tab 221, two non-overlapping first pole tabs are bent into a row, and when a plurality of second pole tabs are bent to form a negative pole tab 222, two non-overlapping second pole tabs are bent into a row, so as to reduce the number of stacked layers of the first pole tabs and / or the second pole tabs in the same row in the thickness direction, so that the plurality of first pole tabs and / or the second pole tabs can be effectively closed, the bending of the pole tabs is convenient, and the space required for bending the pole tabs is reduced, thereby improving the energy density of the battery cell 20; and the thickness of each row of the bent positive pole tab 221 and the negative pole tab 222 is thinned, which is also conducive to improving the pole tab welding yield. At the same time, the positive pole tab 221 and the negative pole tab 222 of this structure can also increase the ultrasonic welding area, reduce the impedance, and thus improve the round-trip efficiency.

[0074] When the number of first tab sheets of each first tab cluster 2211 is the same and 1 / N, the heights of the N first tab clusters 2211 after bending can be made equal, thereby minimizing the occupied space and further improving the energy density. As the value of N increases, the number of first tab sheets that are not overlapped increases, which can further reduce the bending space.

[0075] When the number of second pole tabs of each second pole tab cluster 2221 is the same and 1 / M, the heights of the M second pole tab clusters 2221 after bending can be made equal, thereby minimizing the occupied space and further improving the energy density. As the value of M increases, the number of second pole tabs that are not overlapped can be increased, which can further reduce the bending space, increase the welding area, and further improve the round-trip efficiency.

[0076] In one embodiment of the present invention, the electrode assembly 22 is a winding structure.

[0077] In this example, the electrode assembly 22 is of a wound type. By reasonably designing the position of the pole tabs on the current collector, at least two of the pole tabs of the positive pole tab 221 can be arranged without overlapping in the thickness direction, and at least two of the pole tabs of the negative pole tab 222 can be arranged without overlapping in the thickness direction after winding. The winding process is simple, the quality is easy to control, and the yield is improved.

[0078] The present invention further provides an electric device, comprising any of the above-mentioned battery devices 100. The battery device 100 of the electric device adopts all the technical solutions of all the above-mentioned embodiments, and thus has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0079] The power-consuming device may be a mobile phone, a laptop computer, a battery car, an electric car, an energy storage station, etc. The present application does not limit the specific type of the power-consuming device. When the power-consuming device includes the battery device 100, the battery device 100 may provide power.

[0080] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A battery device, characterized in that: The invention comprises a battery cell, wherein the battery cell comprises a shell and an electrode assembly disposed in the shell, wherein the electrode assembly comprises a positive electrode sheet, a negative electrode sheet and a spacer disposed therebetween; The electrode assembly further includes a positive electrode tab and a negative electrode tab, wherein the positive electrode tab includes a plurality of first electrode tab sheets, and a plurality of the first electrode tab sheets are extended from the sides of the positive electrode sheets at different layers, and the negative electrode tab includes a plurality of second electrode tab sheets, and a plurality of the second electrode tab sheets are extended from the sides of the negative electrode sheets at different layers; Wherein, the plurality of first electrode tab sheets form N first electrode tab clusters, the N first electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each of the first electrode tab clusters is composed of 1 / N of the plurality of first electrode tab sheets, wherein N is a positive integer, and N is greater than or equal to 2; The plurality of second electrode tab sheets form M second electrode tab clusters, the M second electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each second electrode tab cluster is composed of 1 / M of the plurality of second electrode tab sheets, wherein M is a positive integer, and M is greater than or equal to 2; Any first electrode tab cluster is spaced apart from any second electrode tab cluster, and any two adjacent ones of the N first electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact, and any two adjacent ones of the M second electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact.

2. The battery device according to claim 1, characterized in that The lateral dimension of the projections of the N first electrode tab clusters in the thickness direction of the electrode assembly is S1, the lateral dimension of the projections of the M second electrode tab clusters in the thickness direction of the electrode assembly is S2, the lateral spacing dimension between the first electrode tab cluster and the second electrode tab cluster with the closest lateral distance in the projection in the thickness direction of the electrode assembly is S3, and the length of the electrode assembly is L, wherein L=S1+S2+S3.

3. The battery device according to any one of claims 1 to 2, characterized in that: There are at least two electrode assemblies, and at least two electrode assemblies are arranged side by side in the shell along the thickness direction of the electrode assembly; At least two of the positive electrode tabs in the paired electrode assemblies are arranged non-overlappingly in the thickness direction of the electrode assembly; and / or at least two of the negative electrode tabs in the paired electrode assemblies are arranged non-overlappingly in the thickness direction of the electrode assembly.

4. The battery device according to claim 3, characterized in that: At least two of the positive electrode tabs in the paired electrode assembly are arranged with their projected edges in the thickness direction of the electrode assembly in contact with each other; and / or, at least two of the negative electrode tabs in the paired electrode assembly are arranged with their projected edges in the thickness direction of the electrode assembly in contact with each other.

5. The battery device according to any one of claims 1 to 2, characterized in that: The battery cell also includes a first adapter plate and a second adapter plate, the first adapter plate includes a pole connecting portion and a first adapter portion connected to each other, the first adapter portion is electrically connected to N first pole lug clusters correspondingly; the second adapter plate includes a pole connecting portion and a second adapter portion connected to each other, the second adapter portion is electrically connected to M second pole lug clusters correspondingly.

6. The battery device according to any one of claims 1 to 2, characterized in that: The battery cell further includes two flanges, one of which is electrically connected to the N first electrode lug clusters, and the other is electrically connected to the M second electrode lug clusters.

7. An electrode assembly, characterized in that: The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator disposed therebetween; The electrode assembly further includes a positive electrode tab and a negative electrode tab, wherein the positive electrode tab includes a plurality of first electrode tab sheets, and a plurality of the first electrode tab sheets are extended from the sides of the positive electrode sheets at different layers, and the negative electrode tab includes a plurality of second electrode tab sheets, and a plurality of the second electrode tab sheets are extended from the sides of the negative electrode sheets at different layers; Wherein, the plurality of first electrode tab sheets form N first electrode tab clusters, the N first electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each of the first electrode tab clusters is composed of 1 / N of the plurality of first electrode tab sheets, wherein N is a positive integer, and N is greater than or equal to 2; The plurality of second electrode tab sheets form M second electrode tab clusters, the M second electrode tab clusters are arranged non-overlappingly in the thickness direction of the electrode assembly, and each second electrode tab cluster is composed of 1 / M of the plurality of second electrode tab sheets, wherein M is a positive integer, and M is greater than or equal to 2; Any first electrode tab cluster is spaced apart from any second electrode tab cluster, and any two adjacent ones of the N first electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact, and any two adjacent ones of the M second electrode tab clusters have projected edges in the thickness direction of the electrode assembly in contact.

8. The electrode assembly according to claim 7, characterized in that The electrode assembly is a wound structure.

9. An electrical device, characterized in that: A battery device comprising the battery device as claimed in any one of claims 1 to 6.

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