Battery and electronic device

Abstract

A battery (2) and an electronic device (3). The battery (2) comprises a tab assembly (1). The tab assembly (1) comprises a tab (100) and a conducting element (200). The tab (100) comprises a current collector (110) comprising a first conductive material layer (112), an insulating material layer (111) and a second conductive material layer (113), the current collector (110) being provided with a through opening (1103). The conducting element (200) comprises a first conducting portion (210), a second conducting portion (220) and a third conducting portion (230). The first conducting portion (210) is provided on a first side of the current collector (110) and electrically connected to the first conductive material layer (112); the second conducting portion (220) is provided on a second side of the current collector (110) and electrically connected to the second conductive material layer (113); and the third conducting portion (230) is provided in the through opening (1103) and electrically connected to the first conducting portion (210) and the second conducting portion (220) respectively.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of battery, in particular to a battery and an electronic device. BACKGROUND

[0002] A battery is a device that converts external energy into electrical energy and stores it inside, to supply power to external devices (such as portable electronic devices) at the required time. Currently, batteries are widely used in mobile phones, tablets, notebook computers and other electronic devices.

[0003] Among them, the pole piece of the battery includes a current collector and an active material layer arranged on the current collector. Currently, some batteries on the market use composite current collectors for pole pieces. Specifically, the composite current collector includes an insulating material layer in the middle, and a conductive material layer arranged on both sides of the insulating material layer; the tab of the battery is arranged on one conductive material layer.

[0004] The applicant of the present application found in the process of implementing the present application that because the insulating material layer is arranged between the two conductive material layers, the two conductive material layers are not conductive; therefore, it is difficult for the electrons of the conductive material layer away from the tab to flow to the tab, and the overcurrent capacity of the pole piece is weak. SUMMARY

[0005] Embodiments of the present application aim to provide a battery and an electronic device to improve the current situation that the two conductive material layers in the pole piece are not conductive.

[0006] Embodiments of the present application use the following technical solutions to solve the technical problems, which specifically include:

[0007] In a first aspect, embodiments of the present application provide a battery. The battery includes a pole piece assembly; the pole piece assembly includes a pole piece and a conductive element, the pole piece includes a current collector, the current collector includes a first conductive material layer, an insulating material layer and a second conductive material layer arranged in layers, and the current collector is provided with a through opening. The conductive element includes a first conductive part, a second conductive part and a third conductive part. The first conductive part is arranged on the first side of the current collector and is electrically connected with the first conductive material layer; the second conductive part is arranged on the second side of the current collector and is electrically connected with the second conductive material layer; the third conductive part is arranged in the through opening and is electrically connected with the first conductive part and the second conductive part respectively. Among them, the first side is the side of the current collector provided with the first conductive material layer, and the second side is the side of the current collector provided with the second conductive material layer.

[0008] The battery provided by the embodiments of the present application can improve the current situation that two conductive material layers in the current current collector are not conductive.

[0009] In some embodiments, the electrode tab assembly includes a first conductive tab and a second conductive tab. The first conductive tab is arranged on the surface of the first conductive material layer and includes a first connecting region and a second connecting region connected to each other. In the first set direction, the projection of the first connecting region falls on the surface of the first conductive material layer, and the projection of the second connecting region falls on the opening. The first set direction is the direction in which the first conductive material layer points to the insulating material layer. The second conductive tab is arranged on the surface of the second conductive material layer and includes a third connecting region and a fourth connecting region connected to each other. In the direction opposite to the first set direction, the projection of the third connecting region falls on the surface of the second conductive material layer, and the projection of the fourth connecting region falls on the opening. At least part of at least one of the second connecting region and the fourth connecting region extends into the opening, and the second connecting region and the fourth connecting region are connected to each other. The first conductive part includes the first connecting region, the second conductive part includes the third connecting region, and the third conductive part includes the second connecting region and the fourth connecting region. In this way, the first conductive material layer is in electronic conduction with the second conductive material layer via the first connecting region, the second connecting region, the fourth connecting region, and the third connecting region in sequence.

[0010] In some embodiments, the electrode tab assembly further includes a tab mounted on the current collector, and the tab is electrically connected to the current collector. The arrangement of the tab enables the electrode tab assembly to be electrically connected to an external power consumption device when the electrode tab assembly is applied to a battery.

[0011] In some embodiments, the tab is welded to the first conductive tab. In this way, the tab is indirectly electrically connected to the current collector via the first conductive tab.

[0012] In some embodiments, the tab is welded to the first conductive sheet to form a welding area; a projection of the welding area along a thickness direction of the current collector is located at least 70% within the through hole. The welding area experiences sharp and repeated temperature fluctuations during welding. The above arrangement is intended to make the welding area as much as possible to be located at the through hole, so as to reduce the impact of temperature changes of the welding area on the current collector; since the current collector is small and fragile in thickness, it is easy to generate thermal stress under the stimulation of sharp and repeated temperature changes, which increases the risk of local damage to the current collector. In addition, the above arrangement will cause the tab to deform slightly towards the through hole in some cases. Since the tab is prevented from deforming outward at the through hole, it is beneficial to reduce the overall thickness of the tab assembly.

[0013] In some embodiments, the tab is riveted to the first conductive sheet and the second conductive sheet. In this way, the tab is indirectly electrically connected to the current collector via the first conductive sheet.

[0014] In some embodiments, the tab includes a base portion, a fixed portion, and an extension portion. The base portion is arranged on the surface of the first conductive sheet, one end of the base portion extends beyond the current collector; the fixed portion is arranged on the surface of the second conductive sheet; the extension portion passes through the first conductive sheet and the second conductive sheet and is connected to the base portion and the fixed portion, respectively. The base portion, the fixed portion, and the extension portion are riveted from the same metal sheet. In this way, the tab is indirectly electrically connected to the current collector via the first conductive sheet.

[0015] In some embodiments, the battery further includes a rivet that sequentially passes through the tab, the first conductive sheet, and the second conductive sheet. In this way, the tab is indirectly electrically connected to the current collector via the first conductive sheet.

[0016] In some embodiments, the through hole extends from the surface of the current collector to the edge of the current collector. This arrangement is beneficial to make the welding area as much as possible to be located at the through hole.

[0017] In some embodiments, the current collector is provided with a plurality of through holes; the first conductive sheet covers each of the through holes, and the second conductive sheet covers each of the through holes.

[0018] In some embodiments, the through hole is rectangular, diamond-shaped, or circular.

[0019] In some embodiments, the first conductive sheet and the second conductive sheet are formed by folding the same metal sheet. Of course, in other embodiments of the present application, the first conductive sheet and the second conductive sheet can also be two separate sheet structures. However, compared with the two being formed by folding the same metal sheet, the two being separate sheet structures can be relatively fixed after being clamped to the current collector, thereby reducing the risk of relative displacement of the first conductive sheet and the second conductive sheet during welding.

[0020] In some embodiments, the first conductive sheet includes a first end connected to the second conductive sheet, and a second end opposite to the first end, the second end extending beyond the current collector. The second end of the first conductive sheet extends beyond the first current collector, thereby constituting the above-mentioned tab.

[0021] In some embodiments, the battery includes a tab including a base, a fixed part, and an extension. The base is provided on the first side of the current collector and is electrically connected to the first conductive material layer, one end of the base extending beyond the current collector; the fixed part is provided on the second side of the current collector and is electrically connected to the second conductive material layer; the extension is provided on the through hole and is connected to the base and the fixed part, respectively. The first conductive part includes the base, the second conductive part includes the fixed part, and the third conductive part includes the extension. In this way, the first conductive material layer realizes electronic conduction with the second conductive material layer through the base, the extension, and the fixed part in sequence.

[0022] In some embodiments, the battery further includes a first conductive sheet provided on the surface of the first conductive material layer, and the base is provided on the surface of the first conductive sheet; and / or the battery further includes a second conductive sheet provided on the surface of the second conductive material layer, and the fixed part is provided on the surface of the second conductive sheet. The provision of the second conductive sheet can avoid the situation that the current collector is deformed too much on the second side due to the penetration of the nail. On the other hand, since the current collector has a small thickness and low strength, the provision of the second conductive sheet also facilitates clamping by an external clamping structure during riveting. At this time, the stress on the area of the current collector covered by the second conductive sheet is relatively uniform, thereby avoiding the risk of damage to the current collector caused by direct contact with the clamping structure.

[0023] In some embodiments, the battery includes two of the tab assemblies and a separator film provided between the two tab assemblies. Among the two tab assemblies, the tabs in one tab assembly constitute the anode tabs of the battery, and the tabs in the other tab assembly constitute the cathode tabs of the battery. The separator film is provided between the two tab assemblies to separate them.

[0024] In a second aspect, the embodiments of the present application further provide an electronic device comprising any one of the above-mentioned batteries. Since the electronic device comprises the above-mentioned battery, the electronic device can also improve the current situation that the two conductive material layers in the current current collector are not conductive. BRIEF DESCRIPTION OF DRAWINGS

[0025] One or more embodiments are illustrated by way of example in the figures that are not intended to be limiting of the embodiments so as to illustrate exemplary principles of the embodiments. The same reference numerals in different figures identify the same element, and these drawings should not be construed as limiting the embodiments.

[0026] Figure 1 A front view of a pole piece assembly according to one of the embodiments of the present application;

[0027] Figure 2 A top view of the pole piece assembly according to one of the embodiments of the present application; Figure 1

[0028] Figure 3 A cross-sectional view of the pole piece assembly according to one of the embodiments of the present application; Figure 1

[0029] Figure 4 A front view of a pole piece according to one of the embodiments of the present application; Figure 1

[0030] A front view of a pole piece according to one of the embodiments of the present application; Figure 5

[0031] A front view of a pole piece according to one of the embodiments of the present application; Figure 6

[0032] A front view of a pole piece according to one of the embodiments of the present application; Figure 7

[0033] A front view of a pole piece according to one of the embodiments of the present application; Figure 8

[0034] A cross-sectional view of a pole piece assembly according to one of the embodiments of the present application; Figure 9

[0035] A cross-sectional view of a pole piece assembly according to one of the embodiments of the present application; Figure 10

[0036] A cross-sectional view of a pole piece assembly according to one of the embodiments of the present application; Figure 11

[0037] A schematic view of a battery according to one of the embodiments of the present application; Figure 12

[0038] A schematic view of an electronic device according to one of the embodiments of the present application.

[0039] ​​​1、pole piece assembly;

[0040] 100、pole piece; 110, current collector; 120, active material layer; 111, insulating material layer; 112, first conductive material layer; 113, second conductive material layer; 1101, long side; 1102, wide side; 1103, through opening; 1102a, first wide side; 1102b, second wide side; 11201, first film-coated area; 11202, first blank area; 11301, second film-coated area; 11302, second blank area;

[0041] 200, conducting element; 210, first conducting part; 220, second conducting part; 230, third conducting part; 240, first conductive tab; 250, second conductive tab; 241, first connecting area; 242, second connecting area; 251, third connecting area; 252, fourth connecting area;

[0042] 300, tab;

[0043] 100b, pole piece; 110b, current collector; 1103b, through opening;

[0044] 100c, pole piece; 110c, current collector; 1103c, through opening;

[0045] 100d, pole piece; 110d, current collector; 1103d, through opening;

[0046] 100e, pole piece; 110e, current collector; 1103e, through opening;

[0047] 1', pole piece assembly; 100', pole piece; 110', current collector; 240', first conductive tab; 250', second conductive tab; 300', tab; 310', base; 320', fixing part; 330', extension;

[0048] 1", pole piece assembly; 100", pole piece; 110", current collector; 111", insulating material layer; 112", first conductive material layer; 113", second conductive material layer; 240", first conductive tab; 250", second conductive tab; 300", tab; 310", base; 320", fixing part; 330", extension; 1103", through opening;

[0049] 2, battery;

[0050] 3, electronic device;

[0051] M, first side; N, second side; X, first direction; Y, second direction; Z1, first set direction; Z2, second set direction. DETAILED DESCRIPTION

[0052] For the purpose of understanding the present application, the present application will be described in further detail below with reference to the drawings and specific embodiments. It needs to be noted that when an element is described as being "fixed" / "connected" / "mounted" to another element, it can be directly on the other element, or one or more intermediate elements can be present therebetween. When an element is described as being "connected" to another element, it can be directly connected to the other element, or one or more intermediate elements can be present therebetween. The terms "vertical", "horizontal", "left", "right", "inner", "outer", and similar expressions used in the present specification are for the purpose of illustration only.

[0053] Unless otherwise defined, all technical and scientific terms used in the present specification have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the present specification are only for the purpose of describing specific embodiments of the present application and are not intended to limit the present application. The term "and / or" as used in the present specification includes any and all combinations of one or more related listed items.

[0054] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0055] In the present specification, the "mounting" includes welding, screwing, clamping, bonding, etc. to fix or limit an element or device to a specific position or place, and the element or device can be kept stationary or movable within a limited range at the specific position or place. The element or device fixed or limited to the specific position or place can be disassembled or cannot be disassembled, which is not limited in the embodiments of the present application.

[0056] First, the present application provides a pole piece assembly. Please refer to Figures 1 to 3Fig. 1 shows a front view, a top view and a cross-sectional view along A-A line of a pole piece assembly 1 according to an embodiment of the present application, which comprises a pole piece 100 and a conducting element 200. The pole piece 100 comprises a current collector 110, which comprises a first conductive material layer 112, an insulating material layer 111 and a second conductive material layer 113 arranged in sequence, and is provided with a through hole 1103. The conducting element 200 comprises a first conducting part 210, a second conducting part 220 and a third conducting part 230, which are all electrically conductive. The first conducting part 210 is arranged on a first side M of the current collector 110 and is electrically connected to the first conductive material layer 112; the second conducting part 220 is arranged on a second side N of the current collector 110 and is electrically connected to the second conductive material layer 113; and the third conducting part 230 is arranged in the through hole 1103 and is electrically connected to the first conducting part 210 and the second conducting part 220 respectively, so that the first conductive material layer 112 and the second conductive material layer 113 are electrically connected. The first side M is a side of the current collector 110 provided with the first conductive material layer 112, and the second side N is a side of the current collector 110 provided with the second conductive material layer 113. The first side M and the second side N are two sides of the current collector 110 along the thickness direction thereof.

[0057] The specific structure of the pole piece 100 and the conducting element 200 will be described in the following.

[0058] For the pole piece 100, please refer to Figure 4 which shows a front view of the pole piece 100, and in combination with Figures 1 to 3 The pole piece 100 comprises a current collector 110 and an active material layer 120. The current collector 110 has a long and thin sheet structure, and its outer edge profile comprises two long edges 1101 arranged at two ends thereof along a first direction X, and two wide edges 1102 arranged at two ends thereof along a second direction Y. The first direction X intersects the second direction Y. The long edge 1101 is a long edge of the current collector 110 in a flat state, and the direction in which the long edge 1101 extends is the direction in which the current collector 110 extends. When the current collector 110 is flat, the long edge 1101 extends straight, and when the current collector 110 is wound, the long edge 1101 extends curvedly. The wide edge 1102 is a wide edge of the current collector 110 in a flat state, and the direction in which the wide edge 1102 extends is the width direction of the current collector 110 in a flat state. In this embodiment, the long edge 1101 is perpendicular to the wide edge 1102, i.e. the first direction X is perpendicular to the second direction Y. Of course, in other embodiments, the long edge 1101 and the wide edge 1102 can also be arranged at other angles. It is worth noting that the thickness of the current collector 110 is much smaller than the thickness of the active material layer 120. The thickness of the current collector 110 is generally less than 200 microns (μm), and the thickness of the current collector on the market is mostly not higher than 100 μm. Figure 2and Figure 3 The thickness of the current collector 110 is shown in the figure to be relatively large for the purpose of showing the structure of the current collector 110, but it should be understood that the thickness ratio between the current collector 110 and the active material layer 120 shown in the figure does not limit the thickness ratio of the actual electrode product.

[0059] For the aforementioned current collector 110, please refer to Figure 2 In combination with other figures, the current collector 110 is a composite current collector in the present embodiment. Specifically, the current collector 110 includes a first conductive material layer 112, an insulating material layer 111, and a second conductive material layer 113 which are sequentially stacked along the thickness direction of the current collector 110. The insulating material layer 111 is made of an insulating material, which is a base material for the first conductive material layer 112 and the second conductive material layer 113, and also physically separates the first conductive material layer 112 and the second conductive material layer 113. Optionally, the insulating material layer 111 includes a polymer material; further optionally, the insulating material layer 111 includes at least one of polyethylene, polypropylene, polystyrene, polymethyl methacrylate, polyvinyl chloride, nylon, polycarbonate, polyurethane, polytetrafluoroethylene, polyethylene terephthalate, epoxy resin, phenolic plastic, polyimide, and melamine formaldehyde resin. The first conductive material layer 112 and the second conductive material layer 113 are made of conductive materials, and are respectively arranged on the two sides of the insulating material layer 111, and the specific material composition thereof is not limited in the present application. For example, in the present embodiment, the electrode sheet 100 is an anode sheet, and the first conductive material layer 112 and / or the second conductive material layer 113 can be made of copper; it can be understood that in other embodiments of the present application, the first conductive material layer 112 and / or the second conductive material layer 113 can also be made of copper alloy, nickel, nickel alloy, and other suitable conductive materials, which are not listed one by one. In addition, in other embodiments of the present application, the electrode sheet 100 can also be a cathode sheet, at this time, the first conductive material layer 112 and / or the second conductive material layer 113 can be made of aluminum, aluminum alloy, and other suitable conductive materials, which are not listed one by one. As for the way of arranging the first conductive material layer 112 and the second conductive material layer 113 on the insulating material layer 111, it can be electroplating, spraying, or gluing, which is not limited in the present application.

[0060] The current collector 110 is provided with a through opening 1103 which penetrates the current collector 110 along the thickness direction of the current collector 110. The through opening 1103 is used for the part of the conductive element 200 to extend into, and the positional relationship between the through opening 1103 and the conductive element 200 will be described in detail later.

[0061] For the aforementioned active material layer 120, please continue to refer to Figure 2The active material layer 120 is disposed on the surface of the current collector 110, which is a material layer for lithium ion insertion or extraction. Specifically, the surface of the first conductive material layer 112 has a first film-coated region 11201 and a first blank region 11202; the first film-coated region 11201 is coated with the active material layer 120, and the first blank region 11202 is a bare region without the active material layer 120. That is, the surface of the first conductive material layer 112 has the first film-coated region 11201 provided with the active material layer 120 and the first blank region 11202 without the active material layer 120. Similarly, the surface of the second conductive material layer 113 also has a second film-coated region 11301 provided with the active material layer 120 and a second blank region 11302 without the active material layer 120. The first blank region 11202 and the second blank region 11302 are oppositely arranged along the thickness direction of the current collector 110.

[0062] In the embodiment, the first blank region 11202 and the second blank region 11302 are located at the same end of the current collector 110. Specifically, the two wide edges 1102 of the current collector 110 are oppositely arranged along the extension direction of the long edge 1101, and the two wide edges 1102 are respectively the first wide edge 1102a and the second wide edge 1102b. The first blank region 11202 extends from the first wide edge 1102a to the second wide edge 1102b, and the second blank region 11302 also extends from the first wide edge 1102a to the second wide edge 1102b. It can be understood that in other embodiments of the present application, the arrangement positions of the first blank region 11202 and the second blank region 11302 can also be adaptively deformed on the basis of the above. For example, in some other embodiments of the present application, the first blank region 11202 and the second blank region 11302 are both located at the middle position of the current collector 110 along the extension direction of the long edge; specifically, the first wide edge 1102a and the second wide edge 1102b are both provided with the first film-coated region 11201 between the first wide edge 1102a and the first blank region 11202, and the first wide edge 1102a and the second wide edge 1102b are both provided with the second film-coated region 11301 between the second wide edge 1102b and the second blank region 11302; the first blank region 11202 and the second blank region 11302 are oppositely arranged.

[0063] For the above on-off element 200, please refer to Figure 3Meanwhile, the conductive element 200 includes a first conductive part 210 arranged on the first side M of the current collector 110, a second conductive part 220 arranged on the second side N of the current collector 110, and a third conductive part 230 arranged on the through hole 1103. The first conductive part 210, the second conductive part 220, and the third conductive part 230 are all electrically conductive parts. The first conductive part 210 is electrically connected to the first conductive material layer 112, and the second conductive part 220 is electrically connected to the second conductive material layer 113. The third conductive part 230 is arranged on the through hole 1103 to be connected to the first conductive part 210 and the second conductive part 220, respectively, so that the first conductive material layer 112 and the second conductive material layer 113 are electrically connected.

[0064] In this embodiment, the conductive element 200 includes a first conductive sheet 240 and a second conductive sheet 250. Specifically, the first conductive sheet 240 and the second conductive sheet 250 are both in a sheet structure. The first conductive sheet 240 is arranged on the surface of the first conductive material layer 112, and the second conductive sheet 250 is arranged on the surface of the second conductive material layer 113. The first conductive sheet 240 includes a first connecting region 241 and a second connecting region 242 connected to each other. The first connecting region 241 is arranged opposite to the first conductive material layer 112 and is arranged on the surface of the first conductive material layer 112. The second connecting region 242 is arranged opposite to the through hole 1103 and at least partially extends into the through hole 1103. The boundary between the first connecting region 241 and the second connecting region 242 is the edge profile of the through hole 1103 on the surface of the first conductive material layer 112. That is, along the first setting direction Z1, the projection of the first connecting region 241 falls on the surface of the first conductive material layer 112, and the projection of the second connecting region 242 falls on the through hole 1103. Optionally, the first conductive sheet 240 entirely covers the through hole 1103. In this way, the second connecting region 242 entirely blocks one end of the through hole 1103 leading to the first conductive material layer 112 and at least partially extends into the through hole 1103. The first connecting region 241 is entirely arranged in a ring shape around the second connecting region 242 and the through hole 1103.

[0065] Similarly, the second conductive sheet 250 includes a third connection region 251 and a fourth connection region 252 connected to each other. The third connection region 251 is arranged opposite to the second conductive material layer 113 and is attached to the surface of the second conductive material layer 113. The fourth connection region 252 is arranged opposite to the through hole 1103 and the second connection region 242, and at least partially extends into the through hole 1103. The boundary between the third connection region 251 and the fourth connection region 252 is the edge profile of the through hole 1103 on the surface of the second conductive material layer 113. That is, along the second setting direction Z2 shown in the figure, the projection of the third connection region 251 falls on the surface of the second conductive material layer 113, and the projection of the fourth connection region 252 falls on the through hole 1103. The fourth connection region 252 is electrically connected to the second connection region 242. In this embodiment, the fourth connection region 252 and the second connection region 242 are fixedly connected by welding, for example, ultrasonic welding or laser welding. Alternatively, the second conductive sheet 250 covers the through hole 1103 as a whole. The fourth connection region 252 seals one end of the through hole 1103 leading to the second conductive material layer 113, and at least partially extends into the through hole 1103. The third connection region 251 is arranged in a ring shape around the fourth connection region 252 and the through hole 1103 as a whole. The arrangement of the first conductive sheet 240 and the second conductive sheet 250 together sealing the through hole 1103 helps to reduce the risk of the material melted at the bonding surface escaping out of the through hole 1103. It is worth noting that the "first setting direction" in this application refers to the direction of the first conductive material layer 112 pointing to the insulating material layer 111, and the "second setting direction" in this application refers to the direction of the second conductive material layer 113 pointing to the insulating material layer 111. The first setting direction Z1 and the second setting direction Z2 are opposite to each other.

[0066] The first conductive sheet 240 includes the first connection region 241, and the second conductive sheet 250 includes the third connection region 251. The third conductive sheet 230 includes the second connection region 242 and the fourth connection region 252, both of which at least partially extend into the through hole 1103. The first conductive material layer 112 is electronically connected to the second conductive material layer 113 via the first connection region 241, the second connection region 242, the fourth connection region 252, and the third connection region 251 in sequence. It can be understood that in other embodiments of the application, one of the second connection region 242 and the fourth connection region 252 at least partially extends into the through hole 1103 and is fixedly connected to the other.

[0067] In the embodiment, the first conductive sheet 240 and the second conductive sheet 250 are formed by folding the same metal sheet and clamped on two surfaces of the current collector 110. Of course, in other embodiments of the application, the first conductive sheet 240 and the second conductive sheet 250 can also be two sheet structures independent of each other; but compared with the same, the folding of the same metal sheet can ensure that the first conductive sheet 240 and the second conductive sheet 250 are relatively fixed after being clamped on the current collector 100, thereby better reducing the risk of relative displacement of the first conductive sheet 240 and the second conductive sheet 250 during welding.

[0068] Further, in order to enable the pole piece assembly 1 to be connected with an external power consuming device when applied to a battery, the pole piece assembly 1 further comprises a tab 300 mounted on the current collector 110 and electrically connected with the current collector 110. Specifically, please continue to refer to Figure 3 , one end of the tab 300 is welded to the first conductive sheet 240, and the other end extends beyond the edge of the current collector 110. Preferably, the projection of the welding area formed by welding the tab 300 and the first conductive sheet 240 along the thickness direction of the current collector 110 is at least 70% located in the through hole 1103; wherein the "welding area" in the present application means the bonding surface formed by the first conductive sheet 240 and the tab 300 during welding. The welding area has a sharp and repeated temperature fluctuation during welding, and the above setting is to make the welding area as much as possible to be located in the through hole 1103, thereby reducing the impact of temperature change of the welding area on the current collector 110; since the current collector 110 is small in thickness and fragile, it is easy to produce thermal stress under the stimulation of sharp and repeated temperature change, which will increase the risk of local damage of the current collector 110. In addition, the above setting will promote the tab 300 to deform slightly towards the through hole 1103 at the position corresponding to the through hole 1103 in some cases, which is beneficial to reduce the overall thickness of the pole piece assembly 1 by avoiding the outward deformation of the tab 300 at the through hole 1103. More preferably, the projection of the welding area along the thickness direction of the current collector 110 does not fall on the current collector 110, but is located in the through hole 1103. As for the number of tabs 300, it can be one as shown in Figure 1 , or a plurality. For example, in some embodiments, the pole piece assembly 1 comprises a plurality of tabs 300, and correspondingly, the pole piece assembly 1 also comprises a plurality of conductive elements 200; each conductive element 200 is arranged at intervals along the direction in which the current collector 110 extends along the long side, and each tab is connected to a conductive element 200.

[0069] It is worth mentioning that although the through hole 1103 can be a single square closed structure on the surface of the first conductive material layer 112 as in the embodiment, its shape and position are actually variable, and the present application does not make specific limitations thereto, as long as it penetrates the current collector 110 along the thickness direction of the current collector 110. For example, Figure 5 A schematic diagram of a pole piece 100b provided by another embodiment of the present application is shown, and the main difference between the pole piece 100b and the pole piece 100 in the above embodiment is that the current collector 110b is provided with a plurality of through holes 1103b, and each through hole 1103b is arranged at intervals. The first conductive sheet and the second conductive sheet respectively cover each through hole 1103b and are respectively welded and fixed in the area corresponding to each through hole 1103b. For another example, Figure 6 A schematic diagram of a pole piece 100c provided by still another embodiment of the present application is shown, and the main difference between the pole piece 100c and the pole piece 100b in the above embodiment is that the through hole 1103c provided by the current collector 110c is circular, rather than square in the pole piece 100b. For still another example, Figure 7 A schematic diagram of a pole piece 100d provided by yet another embodiment of the present application is shown, and the main difference between the pole piece 100d and the pole piece 100b in the above embodiment is that the through hole 1103d provided by the current collector 110d is prismatic, rather than square in the pole piece 100b. For still another example, Figure 8 A schematic diagram of a pole piece 100e provided by yet another embodiment of the present application is shown, and the main difference between the pole piece 100e and the pole pieces in the above embodiments is that the contour of the through hole 1103e on the surface of the first conductive material layer 112e extends to the edge of the current collector 110e, that is, the contour of the through hole 1103e on the surface of the first conductive material layer 112e is not closed.

[0070] It should be understood that even though the tab 300 is fixed to the first conductive sheet 240 by welding in the above embodiments, the present application is not limited thereto, as long as the tab 300 is fixed to the first conductive sheet 240 and connected with the first conductive sheet 240. In other embodiments of the present application, the tab 300 can also be riveted to the first conductive sheet 240 and the second conductive sheet 250. For example, please refer to Figure 9 which shows a cross-sectional schematic diagram of a pole piece assembly 1' provided by another embodiment of the present application (the cross-sectional view can refer to the cross-sectional view of Figure 3 ), please refer to Figure 3The tab 300' is fixed to the first conductive sheet 240 and the second conductive sheet 250 by self-riveting. Specifically, the tab 300' includes a base 310', a fixing portion 320', and an extension portion 330'. The base 310' is in the form of a sheet, one end of which is arranged on the surface of the first conductive sheet 240', and the other end extends beyond the current collector 110' for electrical connection with the above-mentioned electrical device. The fixing portion 320' is arranged on the surface of the second conductive sheet 250'. The extension portion 330' is arranged between the base 310' and the fixing portion 320', one end of which is connected to the base 310', and the other end passes through the through hole 1103' and the first conductive sheet 240' and the second conductive sheet 250' to be connected to the fixing portion 320'. The base 310', the fixing portion 320', and the extension portion 330' are formed by riveting a metal sheet, and the riveting process of the metal sheet to form the tab 300' is as follows: first, a sheet of metal is arranged on the surface of the first conductive sheet 240'; then, a nail is passed through the metal sheet, the first conductive sheet 240', and the second conductive sheet 250' from the side of the metal sheet away from the first conductive sheet 240', so that the metal sheet forms the base 310' still on the surface of the first conductive sheet 240', and the extension portion extending from the base 310' to the end portion on the side of the second conductive sheet 250' away from the current collector 110', which is formed during the process of passing the nail through the metal sheet; then, the portion of the extension portion extending out of the surface of the second conductive sheet 250' is pressed towards the second conductive sheet 250', so that the portion of the extension portion extending out of the surface of the second conductive sheet 250' is fixed to the surface of the second conductive sheet 250' to form the fixing portion 320', and the portion of the extension portion extending from the surface of the first conductive sheet 240' to the surface of the second conductive sheet 250' forms the extension portion 330'. For example, in some other embodiments of the present application, the tab assembly further includes a rivet, and the tab 300 is fixed to the first conductive sheet 240 and the second conductive sheet 250 by the rivet. Specifically, the rivet passes through the tab 300, the first conductive sheet 240, and the second conductive sheet 250 in sequence, one end of which abuts against the tab 300, and the other end of which abuts against the second conductive sheet 250, so that the tab 300, the first conductive sheet 240, and the second conductive sheet 250 are fixed.

[0071] In addition, even if the tab 300 is indirectly mounted on the current collector 110 through the first conductive sheet 240 in the embodiments of the present application, the present application is not limited thereto. For example, in some other embodiments of the present application, the tab 300 is directly mounted on the surface of the current collector 110, i.e., the first blank area 11202 or the second blank area 11302. For another example, in some other embodiments of the present application, the tab assembly 1 does not additionally include the tab 300, but the first conductive sheet 240 and / or the second conductive sheet 250 constitute the tab as described above; specifically, the first conductive sheet 240 includes a first end and a second end opposite to each other in the extending direction, the first end is connected with the second conductive sheet 250, and the second end extends beyond the first current collector, thereby constituting the tab as described above.

[0072] In summary, the tab assembly 1 provided by the embodiments of the present application includes the tab 100 and the conductive element 200. The current collector 110 of the tab 100 includes the first conductive material layer 112, the insulating material layer 111 and the second conductive material layer 113 which are sequentially stacked, and is provided with the through opening 1103. The first conductive part 210 of the conductive element 200 is arranged on the first side M of the current collector 110 and is electrically connected with the first conductive material layer 112; the second conductive part 220 of the conductive element 200 is arranged on the second side N of the current collector 110 and is electrically connected with the second conductive material layer 113; and the third conductive part 230 of the conductive element 200 is arranged in the through opening 1103 and is electrically connected with the first conductive part 210 and the second conductive part 220, respectively.

[0073] At present, the batteries using the composite current collector in the market are fixed with the tabs through the ultrasonic welding method. The high temperature generated by the welding causes the insulating material layer in the middle of the composite current collector to locally melt at the corresponding position, and causes the two conductive material layers to be in contact and conductive. However, this has a high uncertainty, because even if the insulating material layer melts, there is a probability that the two conductive material layers are not in electrical contact. When the two conductive material layers are not in electrical contact or have poor contact, the electrons in one of the conductive material layers on the side away from the tab are difficult to flow to the other, thereby making the overcurrent capacity of the tab weak. In the tab assembly 1 provided by the embodiments of the present application, the first conductive material layer 112 realizes electrical conduction with the second conductive material layer 113 through the first conductive part 210, the third conductive part 230 and the second conductive part 220 in sequence. That is, the tab assembly 1 provided by the embodiments of the present application can improve the current situation that the two conductive material layers in the current collector are not conductive.

[0074] It is worth mentioning that, although the conductive element 200 in the above embodiment includes the first conductive sheet 240 electrically connected with the first conductive material layer 112, and the second conductive sheet 250 electrically connected with the second conductive material layer 113, and both are welded and fixed in the through port 1103, so that the first conductive material layer 112 and the second conductive material layer 113 are electronically conductive, the present application is not limited thereto; as long as the conductive element 200 includes the first conductive part 210, the second conductive part 220 and the third conductive part 230 respectively, wherein the first conductive part 210 is electrically connected with the first conductive material layer 112, the second conductive part 220 is electrically connected with the second conductive material layer 113, and the third conductive part 230 is electrically connected with the first conductive part 210 and the second conductive part 220 respectively through the through port 1103. For example, Figure 10 A cross-sectional view of the pole piece assembly 1" provided by another embodiment of the present application is shown (the cross-sectional view can refer to the cross-sectional view of the pole piece assembly 1' in the above embodiment, and the cross-sectional view of the pole piece assembly 1" is shown in FIG. 6B). Figure 3 The pole piece assembly 1" still includes the pole piece 100" and the conductive element 200". The conductive element 200" in the pole piece assembly 1" includes the tab 300", that is, the pole piece assembly 1" in the present embodiment makes the first conductive material layer 112" and the second conductive material layer 113" electronically conductive through the tab 300".

[0075] Specifically, the tab 300" includes a base part 310", a fixed part 320" and an extension part 330". The base part 310" is in a sheet structure as a whole, and is located on the first side of the current collector 110". One end of the base part 310" is electrically connected with the first conductive material layer 112, and the other end extends beyond the current collector 110" for electrical connection with the above-mentioned electrical device. The fixed part 320" is located on the second side of the current collector 110", and is electrically connected with the second conductive material layer 113". The extension part 330" is located between the base part 310" and the fixed part 320", and one end of the extension part 330" is connected with the base part 310", and the other end passes through the first conductive sheet 240" and the second conductive sheet 250" from the through port 1103", so as to be connected with the fixed part 320". In the present embodiment, the first conductive part of the conductive element 200" includes the above-mentioned base part 310", the second conductive part of the conductive element 200" includes the above-mentioned fixed part 320", and the third conductive part of the conductive element 200" includes the above-mentioned extension part 330".

[0076] In this embodiment, the tab assembly 1" also includes a first conductive tab 240" and a second conductive tab 250". The first conductive tab 240" is arranged on the surface of the first conductive material layer 112", and the second conductive tab 250" is arranged on the surface of the second conductive material layer 113". The base 310" is arranged on the surface of the first conductive tab 240", and the fixing portion 320" is arranged on the surface of the second conductive tab 250". The base 310", the fixing portion 320", and the extension portion 330" are riveted from the same metal sheet, and the riveting process of the metal sheet to form the tab 300" is roughly as follows: first, a sheet-shaped metal sheet is arranged on the surface of the first conductive tab 240"; then, a nail is used to sequentially pass through the metal sheet, the first conductive tab 240", and the second conductive tab 250" from the side of the metal sheet away from the first conductive tab 240", so that the metal sheet forms the base 310" still on the surface of the first conductive tab 240", and the extension portion extending from the base 310" to the end portion on the side of the second conductive tab 250" away from the current collector 110", the extension portion being formed during the process of the nail passing through the metal sheet, and the through hole 1103" is formed on the current collector 110"; then, the portion of the extension portion protruding out of the surface of the second conductive tab 250" is compacted towards the second conductive tab 250", so that the portion of the extension portion protruding out of the surface of the second conductive tab 250" is reversely fixed on the surface of the second conductive tab 250" to form the fixing portion 320", and the portion of the extension portion extending from the surface of the first conductive tab 240" to the surface of the second conductive tab 250" forms the extension portion 330". Among them, the arrangement of the second conductive tab 250" can avoid the situation that the current collector 110" is deformed too much on the second side caused by the nail passing through, and on the other hand, since the thickness of the current collector is small and the strength is low, the arrangement of the second conductive tab 250" also facilitates the clamping by the external clamping structure during the riveting process, at this time the stress on the covered area of the current collector by the second conductive tab 250" is more uniform, thereby avoiding the hidden danger of damage to the current collector caused by the direct contact of the current collector with the clamping structure. Of course, in other embodiments of the present application, the first conductive tab 240" can be omitted, and accordingly the base 310" of the tab 300" is directly arranged on the surface of the first conductive material layer 112"; and / or the second conductive tab 250" can be omitted, and accordingly the fixing portion 320" of the tab 300" is directly arranged on the surface of the second conductive material layer 113".

[0077] Based on the same inventive concept, the present application also provides a battery; please refer to Figure 11 which shows a schematic diagram of the battery 2, and in combination with Figures 1 to 10The battery 2 comprises the tab assembly as described in any of the above embodiments. In this embodiment, the battery 2 comprises two of the above tab assemblies and a separator. Specifically, the tabs in one of the two tab assemblies constitute the anode tabs of the battery 2, and the tabs in the other of the two tab assemblies constitute the cathode tabs of the battery 2. The separator is arranged between the two tab assemblies to separate them. It can be understood that, even though the battery 2 in this embodiment comprises two of the above tab assemblies, in some other embodiments of the present application, the battery 2 can comprise only one of the above tab assemblies, a conventional tab, and a conventional tab. Specifically, the tabs in the tab assembly constitute the positive tabs (or negative tabs) of the battery 2, the tabs in the tab assembly constitute the positive tabs (or negative tabs) of the battery 2, the conventional tab constitutes the negative tab (or positive tab) of the battery 2, and the conventional tab constitutes the negative tab (or positive tab) of the battery 2.

[0078] In some embodiments, to further reduce the internal resistance of the tab assembly, the tab assembly comprises a plurality of tabs, and the tabs are electrically connected to each other. Specifically, the tabs are arranged in a spaced manner along the direction in which the current collector extends along the long side. The tab assembly is arranged in a roll shape along the long side of the current collector, so that the tabs are located at different layers of the roll-shaped structure, and the tabs are arranged in alignment and fixed to each other. In this way, the portions of the current collector located at different layers are electrically connected through the tabs, and this arrangement can reduce the overall internal resistance of the tab assembly to a certain extent.

[0079] Due to the inclusion of the above tab assembly, the battery 2 can also improve the current situation that the two layers of conductive materials in the current current collector are not conductive.

[0080] Based on the same inventive concept, another embodiment of the present application also provides an electronic device 3. Specifically, please refer to Figure 12 which shows a schematic diagram of the electronic device 3, and in combination with Figures 1 to 11 the electronic device 3 comprises the battery 2 as described in any of the above embodiments. In this embodiment, the electronic device is a mobile phone; it can be understood that in some other embodiments of the present application, the electronic device can also be a tablet, a computer, a drone, a remote controller, an electric vehicle, or any other electronic device.

[0081] Due to the inclusion of the above tab assembly, the electronic device 3 can also improve the current situation that the two layers of conductive materials in the current current collector are not conductive.

[0082] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; under the idea of the present application, the technical features in the above examples or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes of different aspects of the present application as described above, which are not provided in details for simplicity; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part 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.

Claims

1. A battery comprising a jellyroll assembly, characterized in that, The pole piece assembly includes a pole piece, a conducting element, and a tab, the pole piece includes a current collector, the current collector includes a first conductive material layer, an insulating material layer, and a second conductive material layer arranged in a stack, the current collector is provided with a through opening, the conducting element includes: a first conductive sheet provided on a first side of the current collector, the first conductive sheet is connected to the first conductive material layer, and the part of the first conductive sheet connected to the first conductive material layer forms a first conducting part; a second conductive sheet provided on a second side of the current collector, the second conductive sheet is connected to the second conductive material layer, and the part of the second conductive sheet connected to the second conductive material layer forms a second conducting part; wherein the first conductive sheet and the second conductive sheet are connected at the through opening, and the part of the first conductive sheet and the second conductive sheet connected at the through opening forms a third conducting part; the first side is a side of the current collector provided with the first conductive material layer, and the second side is a side of the current collector provided with the second conductive material layer; the tab is provided on the surface of the first conductive sheet and connected to the first conductive sheet.

2. The battery of claim 1, wherein a first conductive sheet is provided on the surface of the first conductive material layer, and includes a first connection region and a second connection region connected to each other, along a first specified direction, a projection of the first connection region falls on the surface of the first conductive material layer, and a projection of the second connection region falls on the through opening, the first specified direction being a direction in which the first conductive material layer points to the insulating material layer; and a second conductive sheet is provided on the surface of the second conductive material layer, and includes a third connection region and a fourth connection region connected to each other, along a direction opposite to the first specified direction, a projection of the third connection region falls on the surface of the second conductive material layer, and a projection of the fourth connection region falls on the through opening, at least part of at least one of the second connection region and the fourth connection region extends into the through opening, and the second connection region and the fourth connection region are connected; the first conducting part includes the first connection region, the second conducting part includes the third connection region, and the third conducting part includes the second connection region and the fourth connection region.

3. The battery of claim 2, wherein, The tab is welded to the first conductive sheet.

4. The battery of claim 3, wherein, The tab and the first conductive sheet are welded to form a welded area; a projection of the welded area along the thickness direction of the current collector is located at least 70% within the through opening.

5. The battery of claim 1, wherein, The tab is riveted to the first conductive sheet and the second conductive sheet.

6. The battery of claim 5, wherein, The tab includes: a base provided on the surface of the first conductive sheet, one end of the base extending beyond the current collector; a fixing part provided on the surface of the second conductive sheet; and an extension part passing through the first conductive sheet and the second conductive sheet, and connected to the base and the fixing part, respectively; the base, the fixing part, and the extension part are riveted from the same metal sheet.

7. The battery of claim 5, wherein, The battery further includes a rivet, the rivet sequentially passes through the tab, the first conductive sheet, and the second conductive sheet.

8. The battery of claim 2, wherein, The through hole extends from the surface of the current collector to the edge of the current collector.

9. The battery of claim 2, wherein, The current collector is provided with a plurality of the through holes. The first conductive sheet covers each of the through holes, and the second conductive sheet covers each of the through holes.

10. The battery of claim 2, wherein, The through hole is rectangular, rhombic or circular.

11. The battery of any one of claims 2-9, wherein, The first conductive sheet and the second conductive sheet are formed by folding a same metal sheet.

12. The battery of claim 2, wherein, The first conductive sheet includes a first end connected to the second conductive sheet, and a second end opposite to the first end, the second end extending beyond the current collector.

13. The battery of claim 1, wherein, The battery includes a tab, the tab including: a base provided on a first side of the current collector and electrically connected to the first conductive material layer, one end of the base extending beyond the current collector; a fixing portion provided on a second side of the current collector and electrically connected to the second conductive material layer; and an extension portion provided on the through hole and connected to the base and the fixing portion respectively; The first conductive sheet is provided on the surface of the first conductive material layer, and the base is provided on the surface of the first conductive sheet; and / or, 14. The battery of claim 13, wherein, The second conductive sheet is provided on the surface of the second conductive material layer, and the fixing portion is provided on the surface of the second conductive sheet. The battery includes two of the tab assemblies and a separator, the separator being provided between the two tab assemblies.

15. The battery of claim 1, wherein, The battery includes the battery as claimed in any one of claims 1 to 15.

16. An electronic device, comprising: The battery includes the battery as claimed in any one of claims 1 to 15.

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