CN214848953U

CN214848953U - Utmost point ear structure, electric core and battery

Info

Publication number: CN214848953U
Application number: CN202120444555.0U
Authority: CN
Inventors: 周龙; 郭敏
Original assignee: Xiamen Haichen New Material Technology Co ltd
Current assignee: Xiamen Haichen New Material Technology Co ltd
Priority date: 2021-03-01
Filing date: 2021-03-01
Publication date: 2021-11-23
Anticipated expiration: 2031-03-01

Abstract

The application provides utmost point ear structure, electric core and battery relates to lithium cell technical field. A tab structure comprises a plurality of layers of tabs which are arranged in a laminated mode, wherein each layer of tab exposes at least part of a conductive surface for leading out current. This application improves the structure that the stromatolite of utmost point ear set up for every layer utmost point ear exposes at least partial conducting layer, makes the utmost point ear can realize drawing forth of every layer utmost point ear through fully contacting with electrically conductive switching piece, reduces process flow and manufacturing cost, avoids utmost point ear to lead to utmost point ear to produce the crackle at the ultrasonic friction vibrations of welding process to the destruction of welding position, improves the goodness and the life of utmost point ear.

Description

Utmost point ear structure, electric core and battery

Technical Field

The application relates to the technical field of lithium batteries, in particular to a tab structure, a battery core and a battery.

Background

In the production process of the lithium battery, a metal foil is usually selected as a current collector, wherein an aluminum foil is selected as a positive current collector, and a copper foil is selected as a negative current collector. In order to improve the energy density and safety of the battery, attention is paid to a composite current collector obtained by compounding a polymer film and a metal coating. However, the polymer film is adopted in the middle of the composite current collector, and the insulating layer formed by the polymer film can not conduct the metal coatings on the two sides. The method commonly adopted at present is to clamp the tab part of a layer of composite current collector by using two layers of metal tabs for welding, and then to weld the multiple layers of metal tabs with the positive electrode tab or the negative electrode tab of the lithium battery respectively. On one hand, the method increases the cost of processing equipment and the technological process, and has low excellent rate. And on the other hand, copper foils or aluminum foils are welded on two sides of the composite current collector, and the metal layer at the welding position of the tab is damaged to generate cracks due to the friction vibration of ultrasonic waves in the welding process.

SUMMERY OF THE UTILITY MODEL

The utility model provides a utmost point ear structure, electric core and battery to improve the utmost point ear of the compound mass flow body and the technical problem that the welding caused the damage to utmost point ear with the metal foil.

In a first aspect, the present application provides a tab structure, which includes a plurality of layers of tabs arranged in a stacked manner, wherein each layer of tab exposes at least a part of a conductive surface for drawing current.

This application improves the structure that the stromatolite of utmost point ear set up for every layer utmost point ear exposes at least partial conducting layer, makes the utmost point ear can realize drawing forth of every layer utmost point ear through fully contacting with electrically conductive switching piece, reduces process flow and manufacturing cost, avoids utmost point ear to lead to utmost point ear to produce the crackle at the ultrasonic friction vibrations of welding process to the destruction of welding position, improves the goodness and the life of utmost point ear.

In one possible implementation, the tab structure has a front surface and a back surface, the conductive surface is disposed on the front surface, and the size of each layer of tabs decreases from the back surface to the front surface.

The structure enables the lug close to the front side in the lug structure to be not completely covered by the lug close to the back side, ensures that each layer of lug has a part of conductive surface to be exposed, and enables each layer of lug to be in contact with the switching piece to realize the leading-out of current.

In one possible implementation mode, the multi-layer tabs are arranged in a staggered and laminated mode to form a step structure.

The multilayer pole lugs with the ladder structures are obtained by folding or cutting the pole lugs, so that each layer of pole lug is facilitated to expose a conductive surface, and the contact between each layer of pole lug and the adapter plate is facilitated.

In one possible implementation mode, the tab structure is provided with through holes, and the aperture of the corresponding through hole of each layer of tab is gradually reduced from one side surface to the other side surface of the tab structure. This configuration is another implementation.

In one possible implementation mode, the tab comprises a base film and a conducting layer arranged on one surface of the base film, the other surface of the base film is free of the conducting layer, at least part of the conducting layer is exposed out of each tab, and the polarity of the conducting layer of each tab is the same. Or the polar ear basal membrane and the conducting layers arranged on the surfaces of the two sides of the basal membrane, wherein the polarities of the conducting layers on the surfaces of the two sides of the basal membrane are the same.

The electrode lug in the embodiment of the application can be an electrode lug of a composite current collector, and also can be an electrode lug of a common current collector. When the tabs are the tabs of the common current collector, because one side of the common current collector is an anode conductive layer and the other side of the common current collector is a cathode conductive layer, when the tabs are arranged in a laminated manner, the contact surfaces of the tabs of the previous layer and the tabs of the next layer are different in polarity, and then a short circuit condition can occur. Therefore, the electrode tab of the common current collector only comprises one conductive layer. When the electrode lug is the electrode lug of a common composite current collector, the electrode lug lamination is arranged to enable the conductive layers on the two adjacent electrode plates to be in contact, and due to the fact that the polarity of the conductive layers which are mutually attached is the same, the short circuit situation cannot occur, the conductive layers can be electrically connected with the switching piece through the conductive layers of the adjacent electrode plates, and the current is led out.

In a second aspect, a battery cell is provided, which includes the above tab structure and a first transition piece, where the first transition piece is in contact with a conductive surface of the tab structure to achieve electrical conduction.

The electric core adopts the tab structure, so that a welding process is not needed, the current is led out through the contact of the tab and the adapter sheet, the damage of ultrasonic friction vibration to the tab in the welding process is reduced, the process flow and the equipment cost are reduced, the optimal rate is improved, and the service life of the electric core is prolonged.

In one possible implementation, the surface of the first contact piece contacting the conductive surface is a plane, or the surface of the first contact piece contacting the conductive surface is a stepped structure matching the conductive surface.

When the contact surface of the adapter plate and the conductive surface is a plane, the adapter plate is in full contact with each layer of pole plate through pressing, and the current is led out. Because the conducting surface of pole piece structure is not the plane, can't laminate with the adaptor piece completely, consequently can fill conducting material in the space between the two with reinforcing conductivity, can also increase the heat dispersion of utmost point ear simultaneously.

The contact surface of the adapter sheet and the conductive surface is of a stepped structure matched with the conductive surface, so that the first adapter sheet is well attached to the lug, the contact area is increased, and the conductive capacity is improved.

In a possible implementation manner, the tab structure further comprises a second adapter sheet matched with the first adapter sheet, and the tab structure is clamped between the first adapter sheet and the second adapter sheet.

After the first rotating connection plate is contacted with each layer of pole lug, a fixing piece is adopted or processed for fixing, so that the first rotating connection plate is prevented from being separated from the pole lug to influence the leading-out of current. The second adapter sheet matched with the first adapter sheet is adopted to realize fixation in the embodiment of the application.

In a possible implementation manner, the second adapter plate is provided with a groove matched with the tab structure and a boss arranged on the side edge of the groove, and the first adapter plate is fixedly connected with the boss.

The lug structure is arranged in the groove, and the lug structure is limited to move in the surface direction. And the conductive surface of the lug structure faces outwards, the first rotating sheet is covered on the lug structure, so that the middle part of the first rotating sheet is contacted with the conductive surface of the lug structure, and the side edge of the first rotating sheet is welded with the lug boss.

In a possible implementation manner, the battery further comprises an elastic piece arranged between the tab structure and the second adapter sheet.

The elastic piece can ensure good contact between the tab structure and the first connecting piece to a greater extent.

In a third aspect, a battery is provided, which includes a casing and the above battery cell, where the battery cell is disposed inside the casing. The battery has better stability and service life.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

Fig. 1 is a schematic structural diagram of a first tab structure provided in an embodiment of the present application;

fig. 2 is a schematic structural diagram of a second tab structure provided in an embodiment of the present application;

fig. 3 is a structural schematic diagram of another view angle of a second tab structure provided in an embodiment of the present application;

fig. 4 is a schematic structural diagram of a third tab structure provided in an embodiment of the present application;

fig. 5 is a structural diagram of a third tab structure provided in an embodiment of the present application from another perspective;

fig. 6 is a schematic structural diagram of a fourth tab structure provided in an embodiment of the present application;

fig. 7 is a schematic structural diagram of a composite current collector pole piece provided in an embodiment of the present application;

fig. 8 is a schematic structural diagram of a common current collector pole piece provided in an embodiment of the present application;

FIG. 9 is an enlarged view of III of FIG. 8;

fig. 10 is a schematic structural diagram of a battery cell provided in an embodiment of the present application;

fig. 11 is a schematic structural diagram of a tab structure and a first transfer sheet according to an embodiment of the present application;

FIG. 12 is an enlarged view of I in FIG. 11;

fig. 13 is a schematic structural diagram of a tab structure and a first transfer sheet according to an embodiment of the present application;

FIG. 14 is an enlarged view of II of FIG. 13;

fig. 15 is a schematic partial structure diagram of a battery cell provided in an embodiment of the present application;

fig. 16 is a schematic partial structure diagram of a battery cell provided in an embodiment of the present application;

fig. 17 is a schematic view of a partial structure of a battery cell provided in an embodiment of the present application.

Icon: 100-tab configuration; 110-a tab; 111-a conductive surface; 112-a base film; 113-a conductive layer; 1131 — a positive conductive layer; 1132 — a negative conductive layer; 1133 — positive electrode active material; 1135 — negative active material; 115-positive electrode tab; 117-negative tab; 119-round hole; 200-electric core; 210-a first transfer tab; 220-a second patch; 221-grooves; 223-boss; 230-elastic member.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it should be noted that the terms "upper", "lower", "outer", and the like indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings or orientations or positional relationships that are conventionally arranged when products of the application are used, and are only used for convenience in describing the application and simplifying the description, but do not indicate or imply that the devices or elements to be referred must have specific orientations, be constructed in specific orientations, and be operated, and thus, cannot be construed as limiting the application. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Some embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a tab structure 100 provided in this embodiment. The present embodiment provides a tab structure 100, which includes multiple layers of tabs 110 stacked together, where each layer of tab 110 exposes at least a portion of a conductive surface 111, and in the present embodiment, the conductive surface 111 is located on a front surface of the tab structure 100, and a surface opposite to the conductive surface 111 serves as a back surface of the tab structure 100.

The general size structure of current pole piece utmost point ear is the same, and the mode of drawing forth of electric current basically does: and directly welding the lugs of the multilayer metal current collectors or welding the lugs of the composite current collectors by adopting transfer welding. The transfer welding is to use two layers of metal tabs to clamp the tab part of one layer of composite current collector for welding, and then to weld the multiple layers of metal tabs with the positive tab 115 or the negative tab 117 of the lithium battery respectively. Therefore, the current is led out from the conventional tab in a welding mode.

This application is for reducing the welding to utmost point ear 110's influence, the structure that sets up utmost point ear 110's stromatolite improves, make every layer utmost point ear 110 expose at least partial conducting surface 111, make utmost point ear 110 can be through fully contacting with electrically conductive switching piece and realize drawing forth of every layer utmost point ear 110, reduce process flow and manufacturing cost, avoid utmost point ear 110 to lead to utmost point ear 110 to produce the crackle at the destruction of welding position in welding process ultrasonic friction vibrations, improve utmost point ear 110's goodness and life. In the embodiment of the present application, the tab 110 may be a tab 110 of a metal foil current collector or a tab 110 of a composite current collector.

In some embodiments of the present application, the plurality of tabs 110 are stacked in a staggered manner to form a stepped structure. In other embodiments of the present application, the multiple layers of tabs 110 may be stacked in other manners such that each layer of tabs 110 exposes at least a portion of the conductive surface 111.

As one implementation, the tab 110 of each layer has the same size and structure. When the tabs 110 are stacked, the tabs 110 are arranged in a staggered manner, for example, by folding the tabs, that is, the tabs 110 on the upper layer are sequentially stacked on the tabs 110 on the bottom layer, the tabs 110 on the bottom layer expose all the conductive surfaces, and the tabs 110 on the upper layer expose part of the conductive surfaces. Each layer of tabs 110 is placed in an offset position relative to the next layer of tabs 110 so that the tabs 110 of the next layer expose a portion of the surface that is electrically conductive. The tab structure 100 obtained by stacking the tabs in the offset manner has a conductive surface 111 having a stepped structure. Since the size of each layer of the tab 110 is the same, the back surface of the tab structure 100 also has a stepped structure. The conductivity of the back is determined by the structure of the pole piece, the back can have conductivity or not, and when the back has conductivity, the back can be contacted with the conductive adapter sheet to lead out the pole piece.

As another implementation manner, the sizes of the tabs 110 in each layer are different, and the sizes of the tabs 110 in each layer arranged in a lamination mode are gradually decreased from the back surface to the front surface. This structure makes utmost point ear 110 when the stromatolite sets up, and the utmost point ear 110 that is close to the positive setting can't shelter from the utmost point ear 110 that is close to the back setting completely for every layer utmost point ear 110 all can expose the surface that the part has the electric conductivity, and last one deck utmost point ear 110 exposes whole conducting layers. In the embodiment of the present application, the tabs 110 with different sizes may be pre-cut during die cutting, or the different sizes of the tabs 110 may be realized by other general processes in the field, and the specific implementation means is not limited in the present application.

In some embodiments of the present application, the tab 110 has a complete planar structure. The tab 110 disposed in a stacked manner is illustrated as a rectangle, but in other embodiments of the present application, the tab 110 may have other shapes, such as an arc shape or a triangle shape, which is not limited in the present application. Please refer to fig. 1, which is a schematic structural diagram of the tab 110 after being stacked and arranged in different lengths and same widths, wherein the length of the tab 110 is the dimension of the tab extending from the root, i.e. the lead-out position of the tab. The tab 110 is stacked along one side to form a stepped structure. Fig. 1 may also be a schematic structural view of the tab 110 having the same length and different widths and stacked, in which the tab 110 has a stepped structure on one side. Referring to fig. 2 to 5, fig. 2 and 3 are schematic structural views illustrating the tab 110 having different widths and stacked, wherein the tab 110 has a stepped structure on two sides. Fig. 4 and 5 are schematic views of a structure in which the tabs 110 have a stepped structure on three sides after being stacked when the tabs 110 have different widths and lengths.

In some embodiments of the present application, the tab 110 is a planar structure with a hole in the middle. In other embodiments of the present application, the tab structure 100 may have a plurality of holes, the shape of the hole may be polygonal, and the hole may be a through hole or a blind hole. Referring to fig. 6, each layer of tab 110 in the stacked arrangement has a circular hole 119 at a corresponding position, and the size of the circular hole 119 decreases progressively from the front side to the back side of the tab structure 100. In this structure, the hole diameter of the circular hole 119 of the upper tab 110 is larger than the hole diameter of the circular hole 119 of the lower tab 110, so that the lower tab 110 can be exposed to a surface having conductivity. In some embodiments of the present application, the tab 110 at the lowermost layer may not have holes, that is, the tab 110 has a complete planar structure, which makes the exposed surface area of the tab 110 at the lowermost layer larger.

It should be noted that, the tabs 110 stacked in this embodiment are the same in structure, that is, each layer of tabs 110 is a tab of a metal current collector or a tab of a composite current collector. In other embodiments of the present application, the tabs of the metal current collector and the tabs of the composite current collector may be alternately stacked. The structure and material of the specific tab 110 are changed according to actual needs, and the application does not limit the tab. The following description will be given taking the composite current collector as an example.

The composite current collector includes a base film 112 and conductive layers 113 disposed on both sides of the base film 112. In some embodiments of the present application, the polarities of the conductive layers 113 on both sides of the base film 112 of the composite current collector are the same, that is, the composite current collector is a positive composite current collector or a negative composite current collector. Specifically, referring to fig. 7, fig. 7 is a schematic structural diagram of a composite current collector pole piece according to an embodiment of the present application. When the pole pieces of the positive composite current collector are stacked, the positive conductive layers 1131 on the adjacent two pole pieces are in contact. Since the conductive layers 113 bonded to each other have the same polarity, short circuit does not occur. And because the pole piece is in contact with the adapter plate on the single side, when the two pole pieces are attached, the positive conducting layer 1131 on the other side of the pole piece is electrically connected with the adapter plate through the positive conducting layer 1131 of the adjacent pole piece, so that the current is led out.

In some embodiments of the present application, the polarities of the conductive layers 113 on two sides of the base film 112 of the composite current collector are different, one side is the positive conductive layer 1131, and the other side is the negative conductive layer 1132, that is, the composite current collector is a shared composite current collector. If the conductive layers 113 having different polarities are formed on both sides of the base film 112 of the tab 110, when the tabs 110 are stacked, the contact surfaces of the tab 110 of the previous layer and the tab 110 of the next layer have different polarities, which may cause a short circuit. The tab 110 of the common current collector includes a base film 112 and a conductive layer 113 disposed on one side surface of the base film 112, and the other side of the base film 112 is not disposed with the conductive layer 113.

Specifically, referring to fig. 8 and 9, fig. 8 is a schematic structural diagram of a common current collector pole piece provided in an embodiment of the present application, and fig. 9 is an enlarged schematic diagram of III in fig. 8. The electrode sheet provided in this embodiment includes a base film 112, a positive electrode conductive layer 1131 and a negative electrode conductive layer 1132 disposed on two sides of the base film 112, a positive electrode active material 1133 disposed on the positive electrode conductive layer 1131, and a negative electrode active material 1135 disposed on the negative electrode conductive layer 1132. The pole piece is of a structure with two side tabs, one side of the pole piece is provided with a positive pole tab 115, and the other side of the pole piece is provided with a negative pole tab 117. The positive tab 115 is composed of a base film 112 and a positive conductive layer 1131 disposed on one side surface of the base film 112, and the negative tab 117 is composed of a base film 112 and a negative conductive layer 1132 disposed on one side surface of the base film 112. When the tab 110 is stacked, the positive conductive layer 1131 or the negative conductive layer 1132 on the tab is attached to the insulating base film 112 on the adjacent tab, and no adverse effect such as short circuit occurs.

In some embodiments of the present application, the conductive layer 113 on the same side of the tab 110 is cut by the tab 110 cutting process, that is, the conductive layer 113 having the same polarity, such as the positive electrode, is cut, and the conductive layer 113 having the other polarity, such as the negative electrode, is remained. In other embodiments of the present application, the tab 110 may be cut by other processes, and the present application does not limit the specific processes.

One surface of the tab structure 100 of the common composite current collector is formed of the conductive surfaces 111 of the plurality of tabs 110, and the other surface (back surface) is a base film 112. Since the base film 112 is insulating, the back surface may not be processed. In some embodiments of the present application, the electrode plate is a positive electrode or a negative electrode composite current collector electrode plate, and both side surfaces of the tab structure 100 are conductive surfaces 111, so that both sides of the tab 110 need to be processed, for example, both sides of the tab 110 are connected to an adapter plate.

Referring to fig. 10, the present application further provides an electrical core 200, which includes a tab structure 100 and a first tab 210, where the first tab 210 contacts an exposed surface of each layer of tabs 110 of the tab structure 100 to achieve electrical conduction.

Referring to fig. 11 and 12, in some embodiments of the present application, a surface of the first rotating sheet 210 contacting the conductive surface 111 is a plane. Because the conductive surface 111 of the tab structure 100 is a trapezoid structure, in an actual processing process, in order to ensure the adhesion of the first tab 210 and the tab structure 100 to a greater degree, the first tab 210 and the tab structure 100 are pressed to make the base film 112 of the tab slightly deform, and the conductive layer 113 and the first tab 210 form a section of contact surface. Further, when the cross-sectional length L of the contact surface is greater than the thickness a of the conductive layer 113 of the pole piece, the first tab 210 makes good contact with the pole piece, and the conductive capability is ensured. Further, L > 1.5A. Alternatively, L ═ 2A or L ═ 2.5A or L ═ 3A.

Although the first tab 210 and the tab structure 100 are pressed to increase the contact area, there is still a gap between the first tab 210 and the pole piece. In some embodiments of the present application, the conductive material is filled in the void region to enhance the conductive capability, and at the same time, the heat dissipation performance of the tab 110 can be increased.

Referring to fig. 13 and 14, in some embodiments of the present application, a surface of the first rotating tab 210 contacting the conductive surface 111 has a stepped structure matching the conductive surface 111. The structure enables the first rotating sheet 210 to be well attached to the tab 110, so that the contact area is increased, and the conductive capacity is improved.

After the first transfer sheet 210 contacts each layer of tab 110, a fixing member or a processing is needed to fix the first transfer sheet 210, so as to avoid the first transfer sheet 210 being separated from the tab 110 to affect the extraction of current. Referring to fig. 15, 16 and 17, fig. 17 is a schematic structural view of the first adaptor sheet 210, the second adaptor sheet 220, the tab structure 100 and the elastic member 230 after combination. The embodiment of the present application uses the second adaptor sheet 220 matched with the first adaptor sheet 210 to realize the fixing. The first adaptor sheet 210 and the second adaptor sheet 220 are respectively disposed on two sides of the tab structure 100, the tab structure 100 is sandwiched between the first adaptor sheet 210 and the second adaptor sheet 220, and the tab structure 100 is fixed by fixing the first adaptor sheet 210 and the second adaptor sheet 220.

Referring to fig. 16, in the present embodiment, the second interposer 220 has a groove 221 matching with the tab structure 100 and a boss 223 disposed at a side of the groove 221, so as to facilitate the disposition of the tab 110, two sides of the groove 221 are communicated with the outside, and the other two sides are disposed with the boss 223. The tab structure 100 is disposed in the groove 221, and movement of the tab structure 100 in the surface direction thereof is limited. And the conductive surface 111 of the tab structure 100 faces outwards, the first transfer sheet 210 is covered on the tab structure 100 so that the middle part of the first transfer sheet 210 is in contact with the conductive surface 111 of the tab structure 100, and the side edge of the first transfer sheet 210 is welded with the boss 223. The shape of the tab structure 100 is a cone, and the groove 221 is a cone structure matched with the tab structure 100.

Referring to fig. 16, in order to improve the fixation of the first adaptor sheet 210 and the second adaptor sheet 220 to the tab structure 100, the battery cell 200 further includes an elastic member 230 disposed between the tab structure 100 and the second adaptor sheet 220. The elastic member 230 can largely ensure good contact between the tab structure 100 and the first transfer sheet 210. The elastic member 230 in this embodiment is an insulating conical body, and in other embodiments of the present application, the elastic member 230 may be a rectangular parallelepiped, and the present application does not limit the structure thereof.

This electric core 200 carries out the centre gripping through first switching piece 210 and second switching piece 220 to utmost point ear structure 100 fixed for the utmost point ear 110 of the compound mass flow body can not carry out the switching welding, reduces ultrasonic frictional vibration among the welding process and to utmost point ear 110's damage, reduces process flow and equipment cost, improves the goodness, improves electric core 200's life.

The present application further provides a battery (not shown in the drawings), which includes a casing (not shown in the drawings) and a battery cell 200, wherein the battery cell 200 is disposed inside the casing. The battery has better stability and service life.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. The tab structure is characterized by comprising a plurality of layers of tabs which are arranged in a laminated mode, wherein at least part of a conductive surface for leading out current is exposed out of each layer of tab.

2. The tab structure of claim 1 wherein the tab structure has a front side and a back side, the conductive surface being disposed on the front side, and the size of each layer of the tab decreasing from the back side to the front side.

3. The tab structure as claimed in claim 1 or 2, wherein a plurality of the tab offset laminations are arranged to form a stepped structure.

4. The tab structure as claimed in claim 1 or 2, wherein the tab structure is provided with through holes, and the aperture of the corresponding through hole of each layer of the tab decreases progressively from one side surface to the other side surface of the tab structure.

5. The tab structure of claim 1, wherein the tab comprises a base film and a conductive layer disposed on one surface of the base film, the other surface of the base film is free of the conductive layer, each tab exposes at least a portion of the conductive layer, and the polarity of the conductive layer of each tab is the same;

or the tab comprises a base film and conducting layers arranged on the surfaces of the two sides of the base film, and the polarity of the conducting layers on the two sides of the base film is the same.

6. A battery cell, characterized by comprising the tab structure of any one of claims 1-5 and a first tab sheet, wherein the first tab sheet is in contact with the conductive surface of the tab structure to achieve electrical conductivity.

7. The battery cell of claim 6, wherein a surface of the first transition piece in contact with the conductive surface is a flat surface, or a surface of the first transition piece in contact with the conductive surface is a stepped structure matching the conductive surface.

8. The electrical core of claim 6, further comprising a second interposer that mates with the first interposer, wherein the tab structure is sandwiched between the first interposer and the second interposer.

9. The electrical core of claim 8, further comprising an elastic member disposed between the tab structure and the second interposer.

10. A battery comprising a housing and the cell of any of claims 6 to 9, the cell being disposed within the housing.