Battery cell and battery

Abstract

The utility model relates to the technical field of batteries, in particular to a battery cell and a battery. The battery cell comprises a battery cell body, the battery cell body comprises at least one pole piece and a tab body extending from the pole piece; the tab assembly is arranged at one end of the battery cell body, and the tab assembly comprises a connecting tab and tab glue arranged on the connecting tab; wherein the tab glue comprises a first glue section and a second glue section which are adjacently arranged in the length direction of the connecting tab, the second glue section is arranged close to the battery cell body, and the thickness of the second glue section is smaller than that of the first glue section; the connecting tab is connected with the tab body to form a connecting area, and the projection of the connecting area on the connecting tab is at least partially overlapped with the second glue section. By applying the technical scheme provided by the invention, the problem of low energy density of the battery in the related technology can be effectively solved.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a battery cell and a battery. Background Art

[0002] Lithium-ion batteries have the advantages of large capacity, small size, light weight and green environmental protection, and have been widely used in industries such as digital electronic products and electric vehicles.

[0003] In the related art, a soft-pack lithium-ion battery generally includes a packaging bag and a battery cell located in the packaging bag. The battery cell usually includes a pole ear body (soft pole ear or foil pole ear) and a connecting pole ear (hard pole ear) welded to the soft pole ear. The hard pole ear is provided with pole ear glue. The opening of the packaging bag can be heat-sealed with the pole ear glue during packaging, thereby ensuring the sealing effect of the connecting pole ear and the packaging bag.

[0004] When welding the tab body and the connecting tab, flat welding is generally used, that is, the connecting tab is directly placed flat on the tab body for welding. However, this welding method will waste the head space of the battery and reduce the volume energy density of the battery. Utility Model Content

[0005] The present application provides a battery cell and a battery to solve the problem of low battery energy density in the related art.

[0006] In one aspect, the present application provides a battery cell, comprising:

[0007] A battery cell body; the battery cell body includes at least one pole piece and a pole ear body extending from the pole piece; a pole ear assembly is arranged at one end of the battery cell body, the pole ear assembly includes a connecting pole ear and a pole ear glue arranged on the connecting pole ear; wherein the pole ear glue includes a first glue segment and a second glue segment arranged adjacent to each other in the length direction of the connecting pole ear, the second glue segment is arranged close to the battery cell body, and the thickness of the second glue segment is less than the thickness of the first glue segment; the connecting pole ear is connected to the pole ear body to form a connecting area, and the projection of the connecting area on the connecting pole ear at least partially overlaps with the second glue segment.

[0008] In some embodiments, a projection of the connecting area on the connecting tab overlaps at least a portion of the second rubber segment and at least a portion of the first rubber segment.

[0009] In some embodiments, the connecting electrode ear includes a first surface and a second surface that are arranged opposite to each other, and the first surface is arranged close to the electrode ear body; the first glue segment includes a first colloid portion and a second colloid portion, the first colloid portion is adhered to the first surface of the connecting electrode ear, and the second colloid portion is adhered to the second surface of the connecting electrode ear; the second glue segment includes a third colloid portion and a fourth colloid portion, the third colloid portion is adhered to the first surface and is arranged adjacent to the first colloid portion, the fourth colloid portion is adhered to the second surface and is arranged adjacent to the second colloid portion, the thickness of the third colloid segment is less than the thickness of the first colloid portion, and the thickness of the fourth colloid portion is less than the thickness of the second colloid portion.

[0010] In some embodiments, the third colloid portion is residual glue or the thickness of the third colloid portion is 0 mm; and / or the fourth colloid portion is residual glue or the thickness of the fourth colloid portion is 0 mm.

[0011] In some embodiments, a projected area of ​​the connection region on the connection tab is less than or equal to an area of ​​the second rubber segment.

[0012] In some embodiments, the length D1 of the second rubber segment in the first direction is between 0.5 mm and 2 mm, and the first direction is the length direction of the connecting tab;

[0013] and / or,

[0014] The length D2 of the connection area in the first direction is between 0.3 mm and 0.8 mm, and the first direction is the length direction of the connection tab;

[0015] and / or,

[0016] The length of the second rubber segment in the first direction is D1, the length of the connecting area in the first direction is D2, and D1 and D2 satisfy: 0.15≤D2 / D1≤1.

[0017] In some embodiments, the thickness of the fourth colloid part is the same as the thickness of the second colloid part, the distance between the end point of the fourth colloid part close to the battery cell body and the end point of the second colloid part close to the battery cell body is H, the thickness of the third colloid part is less than the thickness of the first colloid part, and the length of the third colloid part in the first direction is D1, and D1 and H satisfy: D1=H.

[0018] In some embodiments, the melting depth of the connection zone is D3, the thickness of the connection tab is D4, and the thickness of the tab body is D5, and D3, D4, and D5 satisfy: D4+0.3D5≤D3≤D4+0.95D5.

[0019] In some embodiments, the connecting tab is welded to the tab assembly and forms a weld mark on the second surface. The weld mark includes a welding protrusion protruding from the second surface. The height of the welding protrusion is less than the thickness of the second colloid.

[0020] In some embodiments, the pole ear body includes a first straight section and a first bent section, the first straight section is connected to the battery cell body, the first straight section is connected to the first bent section and is set at an angle to the first bent section; the connecting pole ear includes a second straight section and a second bent section set at an angle to the second straight section, the second bent section is arranged opposite to the first bent section, and the pole ear glue stripping area and the connection area are both located in the second bent section; the maximum distance of the pole ear assembly in the second direction is smaller than the maximum distance of the battery cell body in the second direction, wherein the second direction is the thickness direction of the battery cell body.

[0021] On the other hand, the present application provides a battery, comprising the above-mentioned battery cell.

[0022] The battery cell provided in the present application includes a battery cell body and a tab assembly, the tab assembly includes a tab body and a connecting tab, the tab body is connected to the battery cell body and is located on the side of the battery cell body, and the connecting tab is connected to the tab body by welding. Tab glue is provided on the connecting tab, and when the battery cell is packaged, the opening of the packaging bag can be heat-sealed with the tab glue, thereby ensuring the packaging effect at the connecting tab. The tab glue includes a first glue segment and a second glue segment, the second glue segment is arranged on the side of the first glue segment close to the battery cell body, and the thickness of the second glue segment is less than the thickness of the first glue segment. The connecting tab and the tab body are connected through a connecting area, so that the connecting area and the second glue segment can overlap at least partially. On the one hand, this arrangement can reduce the tab glue content in the connecting area, thereby reducing the interference of the tab glue on the tab connection, and ensuring the connection strength between the connecting tab and the tab body. On the other hand, it can also increase the overlapping area between the connecting tab and the tab body, reduce the overall length of the battery cell, ensure the miniaturization of the battery cell design, and thus help to improve the energy density of the battery. Therefore, the technical solution of the present application has the advantages of high energy density of the battery and high connection strength of the tabs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0024] Figure 1 A schematic diagram of the structure of a welding tab assembly in the related art is shown;

[0025] Figure 2 A side view of a battery cell provided in one embodiment of the present application;

[0026] Figure 3 for Figure 2 A side view of a connecting tab of a battery cell;

[0027] Figure 4 for Figure 2 A top view of a battery cell;

[0028] Figure 5 for Figure 2 Schematic diagram of the structure of the battery cell after bending;

[0029] Figure 6 A side view of a battery cell provided in another embodiment of the present application;

[0030] Figure 7 for Figure 6 A side view of a connecting tab of a battery cell;

[0031] Figure 8 for Figure 6 A top view of a battery cell;

[0032] Fig. 9 for Figure 6 Schematic diagram of the structure of the battery cell after bending;

[0033] Fig.10 for Figure 2 The actual picture of the battery cell's tab body and the connecting tab after welding, among which, Fig.10 It shows the state that the tab glue is provided with a single-sided peeling area;

[0034] Fig.11 for Figure 6 The actual picture of the battery cell's tab body and the connecting tab after welding, among which, Fig.11 It shows the state where the tab glue is provided with a double-sided peeling area.

[0035] Description of reference numerals:

[0036] 10. Battery cells;

[0037] 100. Battery cell body;

[0038] 200. Tab assembly;

[0039] 300, tab body; 310, first straight section; 320, first bent section;

[0040] 400, connecting tab; 401, first surface; 402, second surface; 410, second straight section; 420, second bending section;

[0041] 500, ear glue; 510, first glue section; 511, first glue part; 512, second glue part; 520, second glue section; 521, third glue part; 522, fourth glue part;

[0042] 600. Connection area. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] In the related art, a soft-pack lithium-ion battery generally includes a packaging bag and a battery cell inside the packaging bag. The battery cell usually includes a pole tab body (soft pole tab or foil pole tab) and a connecting pole tab (hard pole tab) welded to the soft pole tab. The hard pole tab is provided with pole tab glue, and the opening of the packaging bag can be heat-sealed with the pole tab glue during packaging, thereby ensuring the sealing effect between the hard pole tab and the packaging bag.

[0045] Figure 1 A comparison diagram of the methods for welding the tab assembly in the related art is shown. Figure 1 As shown, when welding the tab body and the connecting tab, the connecting tab 400 is generally placed directly on the tab body 300 for welding. In order to ensure that there is no interference of the tab glue 500 between the connecting tab 400 and the tab body 300 during welding, the overlapping area between the connecting tab 400 and the tab body 300 is shorter, resulting in a longer overall length of the battery and reduced energy density of the battery.

[0046] Therefore, there is currently a lack of a battery cell structure that takes into account both battery miniaturization and tab welding strength.

[0047] In view of this, the present application provides a battery cell, a battery and an electrical device, wherein a tab glue stripping area is provided on the connecting tab, and a portion of the tab glue between the connecting tab 400 and the tab body 300 is stripped off, so that the connecting tab 400 and the tab body 300 can be in direct contact with each other, thereby ensuring the connection strength between the two. On the other hand, the overlapping area between the connecting tab 400 and the tab body 300 can be increased, thereby reducing the overall length of the battery cell, ensuring the miniaturization of the battery cell design, and thus helping to improve the energy density of the battery.

[0048] The following is a description of the battery cell and battery provided in the embodiment of the present application in conjunction with the accompanying drawings. It should be noted that the battery cell provided in the embodiment of the present application can be a wound battery cell or a laminated battery cell. This embodiment takes a laminated battery cell as an example to introduce the structure and function of the battery cell.

[0049] It should also be noted that the battery in this embodiment can be a secondary battery, that is, the battery in the embodiment of the present application can be charged and discharged and recycled. The specific type of battery may include but is not limited to lithium batteries, etc., and the scenarios in which the battery can be used include but are not limited to electronic products, energy storage equipment, transportation vehicles and other electrical equipment, such as mobile communication equipment, new energy vehicles, drones, etc., which are not specifically limited in the embodiments of the present application.

[0050] like Figures 2 to 7 As shown, the battery cell 10 provided in this embodiment includes: a battery cell body 100 and a tab assembly 200 .

[0051] Specifically, the battery cell body 100 includes at least one pole piece and a pole tab body 300 extending from the pole piece. The pole tab assembly 200 is arranged at one end of the battery cell body 100, and the pole tab assembly 200 includes a connecting pole tab 400 and a pole tab glue 500 arranged on the connecting pole tab 400; wherein the pole tab glue 500 includes a first glue segment 510 and a second glue segment 520 adjacently arranged in the length direction of the connecting pole tab 400, the second glue segment 520 is arranged close to the battery cell body 100, and the thickness of the second glue segment 520 is less than the thickness of the first glue segment 510; the connecting pole tab 400 is connected to the pole tab body 300 and forms a connecting area, and the projection of the connecting area on the connecting pole tab 400 at least partially overlaps with the second glue segment 520.

[0052] Applying the technical solution of this embodiment, the battery cell provided by this application includes a battery cell body and a tab assembly, the tab assembly includes a tab body and a connecting tab, the tab body is connected to the battery cell body and is located on the side of the battery cell body, and the connecting tab is connected to the tab body by welding. Tab glue is provided on the connecting tab, and when the battery cell is packaged, the opening of the packaging bag can be heat-sealed with the tab glue, thereby ensuring the packaging effect at the connecting tab. The tab glue includes a first glue segment and a second glue segment, the second glue segment is arranged on the side of the first glue segment close to the battery cell body, and the thickness of the second glue segment is less than the thickness of the first glue segment. The connecting tab and the tab body are connected through a connecting area, so that the connecting area and the second glue segment can overlap at least partially. This arrangement can, on the one hand, reduce the tab glue content in the connecting area, thereby reducing the interference of the tab glue on the tab connection, and ensure the connection strength between the connecting tab and the tab body. On the other hand, it can also increase the overlapping area between the connecting tab and the tab body, reduce the overall length of the battery cell, ensure the miniaturization of the battery cell design, and thus help to improve the energy density of the battery. Therefore, the technical solution of the present application has the advantages of high energy density of the battery and high connection strength of the tabs.

[0053] It should be noted that the second glue segment 520 is formed by peeling the tab glue 500. Exemplarily, the second glue segment 520 is formed by placing the tab glue 500 on a laser device, irradiating the tab glue with a high-power density laser beam to rapidly melt and vaporize the tab glue, and at the same time, using a high-speed airflow to blow away the molten material to achieve tab glue peeling.

[0054] It should also be noted that the second glue section 520 can be formed by peeling off only the overflow glue section, or by peeling off the overflow glue section and a part of the main section, as long as the length of the tab glue in the x direction can meet the packaging requirements of the packaging bag.

[0055] When forming the second glue section 520, only the tab glue on one side of the connecting tab can be peeled off to form a single tab glue peeling zone, or all the tab glue on both sides of the connecting tab can be peeled off to form a double-sided tab glue peeling zone.

[0056] In some embodiments, the projection of the connection area 600 on the connection tab 400 overlaps with at least part of the second adhesive segment 520 and at least part of the first adhesive segment 510, so that the connection area 600 has sufficient space to ensure the stability of the tab connection.

[0057] Specifically, Figures 2 to 4 as well as Fig.10 As shown, the connecting tab 400 includes a first surface 401 and a second surface 402 that are arranged opposite to each other, and the first surface 401 is arranged close to the tab body 300; the first glue segment 510 includes a first colloid portion 511 and a second colloid portion 512, the first colloid portion 511 is adhered to the first surface 401 of the connecting tab 400, and the second colloid portion 512 is adhered to the second surface 402 of the connecting tab 400; the second glue segment 520 includes a third colloid portion 521 and a fourth colloid portion 522, the third colloid portion 521 is adhered to the first surface 401 and is arranged adjacent to the first colloid portion 511, and the fourth colloid portion 522 is adhered to the second surface 402 and is arranged adjacent to the second colloid portion 512, the thickness of the third colloid segment is less than the thickness of the first main body portion, and the thickness of the fourth colloid portion 522 is equal to the thickness of the second main body portion.

[0058] In the above structure, the first surface 401 of the connecting tab 400 is in contact with the tab body 300, so the third colloid portion 521 is arranged on the first surface 401, so that during welding, the first surface 401 of the connecting tab 400 and the tab body 300 are less affected by the tab glue, thereby ensuring the connection strength between the two.

[0059] It should be noted that the third colloid part 521 is formed on the side of the first colloid part 511 close to the battery body 100. Specifically, the third colloid part 521 can be formed by peeling off the overflowing glue section close to the battery body 100 from the first glue section 510. Of course, the third colloid part 521 can also be formed by peeling off the overflowing glue section close to the battery body 100 from the first glue section 510 and a small part of the first colloid part 511. In some embodiments, the third colloid part 521 is residual glue or the thickness of the third colloid part 521 is 0 mm.

[0060] In the above structure, "residual glue" refers to the tab glue remaining on the first surface or the second surface when the tab glue is peeled off. When peeling off the tab glue, the tab glue in the predetermined area should be peeled off from the first surface or the second surface as much as possible (that is, the thickness of the third colloid part 521 is 0 mm), but sometimes there will be residual glue, which can be left on the first surface or the second surface and will not affect the welding strength of the tab.

[0061] Furthermore, in some embodiments, the projected area of ​​the connection region 600 on the connecting tab 400 is less than or equal to the area of ​​the second glue segment 520, that is, the connection region 600 is entirely within the range of the second glue segment 520, thereby reducing the negative impact of the tab glue during the tab connection.

[0062] Specifically, the connecting tab and the tab body can be connected by welding, and the connecting area 600 is a welding area, so that the entire welding area falls within the range of the second glue section 520, reducing the heat absorption of the tab glue welding, so that the welding energy is applied to connecting the connecting tab and the tab body, ensuring the connection stability between the connecting tab and the tab body.

[0063] It should also be noted that if Figure 3 As shown, the thickness of the fourth colloid part 522 is the same as the thickness of the second colloid part 512, the distance between the end point of the fourth colloid part 522 close to the battery body 100 and the end point of the second colloid part 512 close to the battery body 100 is H, the thickness of the third colloid part 521 is less than the thickness of the first colloid part 511, and the length of the third colloid part 521 in the first direction is D1, and D1 and H satisfy: D1 = H. It can be seen that the third colloid part 521 is formed by peeling the ear glue 500.

[0064] The following describes the embodiments in which two tab glue stripping zones are provided in conjunction with the accompanying drawings.

[0065] like Figures 6 to 8 as well as Fig.11As shown, the connecting tab 400 includes a first surface 401 and a second surface 402 that are arranged opposite to each other, and the first surface 401 is arranged close to the tab body 300; the first glue segment 510 includes a first colloid portion 511 and a second colloid portion 512, the first colloid portion 511 is adhered to the first surface 401 of the connecting tab 400, and the second colloid portion 512 is adhered to the second surface 402 of the connecting tab 400; the second glue segment 520 includes a third colloid portion 521 and a fourth colloid portion 522, the third colloid portion 521 is adhered to the first surface 401 and is arranged adjacent to the first colloid portion 511, the fourth colloid portion 522 is adhered to the second surface 402 and is arranged adjacent to the second colloid portion 512, the thickness of the third colloid portion 521 is less than the thickness of the first colloid portion, and the thickness of the fourth colloid portion 522 is less than the thickness of the second colloid portion.

[0066] In the above structure, the thickness of the third colloid part 521 is less than that of the first colloid part, and the thickness of the fourth colloid part 522 is less than that of the second colloid part. That is to say, the tab glue stripping area includes two, the third colloid part 521 is formed by stripping a part of the first glue segment 510, and the fourth colloid part 522 is formed by stripping a part of the second glue segment 520. The fourth colloid part 522 is provided so that the welding device can directly contact the second surface 402. Compared with only one third colloid part 521, the two stripping areas can prevent the tab glue from absorbing heat during welding, thereby helping to improve the welding effect of the tab body 300 and the connecting tab 400.

[0067] It should be noted that the fourth colloid part 522 is attached to the second surface 402 and is disposed adjacent to the second colloid part 512. Specifically, the fourth colloid part 522 can be formed by peeling off the overflowing section of the second colloid part 512 near the battery body 100. Of course, the fourth colloid part 522 can also be formed by peeling off the overflowing section of the second colloid part 512 near the battery body 100 and a small part of the second colloid part 512.

[0068] It should also be noted that, in some embodiments, the fourth colloid portion 522 is residual glue or the thickness of the fourth colloid portion 522 is 0 mm.

[0069] In the above structure, "residual glue" refers to the tab glue remaining on the first surface or the second surface when the tab glue is peeled off. When peeling off the tab glue, the tab glue in the predetermined area should be peeled off from the first surface or the second surface as much as possible (that is, the thickness of the fourth colloid part 522 is 0 mm), but sometimes there will be residual glue, which can be left on the first surface or the second surface and will not affect the welding strength of the tab.

[0070] The dimensions of the connection area are described below with reference to the accompanying drawings.

[0071] Specifically, Figure 2 and Figure 6As shown, in some embodiments, the third colloid portion 521 is in the first direction (eg Figure 2 The length D1 in the x direction (ie, the length direction of the connecting tab 400 ) is between 0.5 mm and 2 mm, so that there is a sufficiently large welding space on the connecting tab 400 .

[0072] The length D2 of the connection area 600 in the first direction may be greater than or equal to the length D1 of the third colloid part 521 in the first direction, or may be less than the length D1 of the third colloid part 521 in the first direction.

[0073] Exemplarily, the length D2 of the connection area 600 in the first direction is smaller than the length D1 of the third colloid part 521 in the first direction. Specifically, the length D2 of the connection area 600 in the first direction is between 0.3 mm and 0.8 mm, thereby ensuring the welding strength between the connection tab 400 and the tab body 300.

[0074] The value that D2 can take can be 0.3mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or any value between 0.3mm-0.8mm.

[0075] It should be noted that D1 and D2 may also satisfy: 0.15≤D2 / D1≤1. Exemplarily, the ratio of D2 / D1 may be 0.15, 0.3, 0.5, 0.8, 1 or any value between 0.3 and 1.

[0076] Furthermore, if Figure 2 As shown, the melting depth of the connection area 600 is D3, the thickness of the connecting tab 400 is D4, and the thickness of the tab body 300 is D5. D3, D4, and D5 satisfy: D4+0.3D5≤D3≤D4+0.95D5. Such a setting can ensure the welding strength between the connecting tab 400 and the tab body 300.

[0077] In some embodiments, the connecting tab 400 is welded to the tab assembly 200 and forms a weld mark on the second surface 402, the weld mark includes a welding protrusion protruding from the second surface 402, and the height of the welding protrusion is less than the thickness of the second glue segment 520. Specifically, the height of the welding protrusion is between 0.5um and 50um, and the thickness of the first glue segment 510 or the second glue segment 520 is between 55um and 200um.

[0078] In some embodiments, it is also necessary to paste protective tape on the weld mark to prevent the uneven structure of the weld mark from scratching the packaging film. Specifically, the packaging film includes a PP layer, an aluminum layer, and a nylon layer from the inside to the outside. If the uneven structure of the weld mark scratches the PP layer, it is easy to cause the battery cell to contact the aluminum layer, causing a short circuit.

[0079] In some embodiments, in order to further reduce the size of the battery cell in the first direction, the tab assembly 200 can be bent to increase the size of the tab assembly in the second direction (eg Figure 2 The size of the tab assembly 200 in the first direction is reduced by reducing the size in the y direction (i.e., the thickness direction of the battery cell) as shown in FIG. It should be noted that the maximum distance of the tab assembly 200 in the second direction needs to be smaller than the maximum distance of the battery cell body 100 in the second direction, so that the thickness of the tab assembly 200 does not exceed the thickness of the battery cell body 100, thereby meeting the low thickness requirement of the battery cell.

[0080] Specifically, Figure 5 Shown and Fig. 9 The pole ear body 300 includes a first straight section 310 and a first bent section 320, the first straight section 310 is connected to the battery cell body 100, the first straight section 310 is connected to the first bent section 320 and is arranged at an angle to the first bent section 320; the connecting pole ear 400 includes a second straight section 410 and a second bent section 420 arranged at an angle to the second straight section 410, the second bent section 420 is arranged opposite to the first bent section 320, and the pole ear glue stripping area and the connection area 600 are both located in the second bent section 420.

[0081] The structure further reduces the size of the battery cell 10 in the first direction by bending the tab body 300 and the connecting tab 400, so that the size of the battery cell 10 in the first direction is smaller than L2, thereby further miniaturizing the battery cell 10 and helping to improve the energy density of the battery.

[0082] It should be noted that after the tab assembly 200 is bent, its dimension in the second direction is between 0.6 mm and 3 mm.

[0083] Furthermore, the angle between the first straight section 310 and the first bent section 320 is between 75° and 100°. Preferably, the first straight section 310 and the first bent section 320 are vertically arranged.

[0084] Accordingly, the angle between the second straight section 410 and the second bent section 420 is between 75° and 100°. Preferably, the second straight section 410 and the second bent section 420 are vertically arranged.

[0085] It should be noted that the connecting tab 400 and the tab body 300 may be pre-bent, welded and finally bent to ensure that the connection area does not cover the bending part, so as to avoid making the tab assembly 200 difficult to bend.

[0086] This embodiment also provides a battery (not shown in the figure), comprising the above-mentioned battery core 10. Since the above-mentioned battery core has the advantages of high strength and small volume, the battery having the same has the advantages of good safety, high stability and high energy density.

[0087] The present application provides an electric device (not shown in the figure), which includes the above-mentioned battery. The electric device includes but is not limited to electronic products, energy storage devices, vehicles, etc. Exemplarily, the electric device can be a mobile communication device, a new energy vehicle, a drone, and other equipment.

[0088] Since the above-mentioned battery has the advantages of good safety, high stability and high energy density, the electrical device having the battery also has the above-mentioned advantages.

[0089] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0090] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0091] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example.

[0092] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or apparatus.

[0093] Finally, it should be noted that the above implementation modes are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned implementation modes, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned implementation modes can still be modified, or some or all of the technical features therein can be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the implementation modes of the present application.

Claims

1. A battery cell, characterized in that: include: A battery cell body; the battery cell body comprises at least one pole piece and a pole ear body extending from the pole piece; A tab assembly is arranged at one end of the battery body, and the tab assembly comprises a connecting tab and a tab glue arranged on the connecting tab; The tab glue comprises a first glue segment and a second glue segment adjacently arranged in the length direction of the connecting tab, the second glue segment is arranged close to the battery cell body, and the thickness of the second glue segment is less than the thickness of the first glue segment; The connecting tab is connected to the tab body to form a connecting area, and a projection of the connecting area on the connecting tab at least partially overlaps with the second rubber segment.

2. The battery cell according to claim 1, characterized in that: The projection of the connecting area on the connecting electrode ear overlaps with at least a portion of the second rubber segment and at least a portion of the first rubber segment.

3. The battery cell according to claim 1, characterized in that: The connecting tab comprises a first surface and a second surface arranged opposite to each other, wherein the first surface is arranged close to the tab body; The first glue section includes a first glue part and a second glue part, the first glue part is adhered to the first surface of the connecting electrode ear, and the second glue part is adhered to the second surface of the connecting electrode ear; The second glue section includes a third colloid part and a fourth colloid part, the third colloid part is adhered to the first surface and is arranged adjacent to the first colloid part, the fourth colloid part is adhered to the second surface and is arranged adjacent to the second colloid part, the thickness of the third colloid part is smaller than the thickness of the first colloid part, and the thickness of the fourth colloid part is smaller than the thickness of the second colloid part.

4. The battery cell according to claim 3, characterized in that: The third colloid part is residual glue or the thickness of the third colloid part is 0 mm; and / or, The fourth colloid part is residual glue or the thickness of the fourth colloid part is 0 mm.

5. The battery cell according to claim 1, characterized in that: The projected area of ​​the connecting region on the connecting tab is smaller than or equal to the area of ​​the second rubber segment.

6. The battery cell according to any one of claims 2 to 5, characterized in that: The length D1 of the second rubber segment in the first direction is between 0.5 mm and 2 mm, and the first direction is the length direction of the connecting tab; and / or The length D2 of the connection area in the first direction is between 0.3 mm and 0.8 mm, and the first direction is the length direction of the connection tab; and / or The length of the second rubber segment in the first direction is D1, the length of the connecting area in the first direction is D2, and D1 and D2 satisfy: 0.15≤D2 / D1≤1.

7. The battery cell according to claim 4, characterized in that: The thickness of the fourth colloid part is the same as that of the second colloid part, the distance between the end point of the fourth colloid part close to the battery cell body and the end point of the second colloid part close to the battery cell body is H, the thickness of the third colloid part is less than the thickness of the first colloid part, the length of the third colloid part in the first direction is D1, D1 and H satisfy: D1=H.

8. The battery cell according to any one of claims 1 to 5, characterized in that: The melting depth of the connection zone is D3, the thickness of the connection tab is D4, and the thickness of the tab body is D5. D3, D4, and D5 satisfy: D4+0.3D5≤D3≤D4+0.95D5.

9. The battery cell according to claim 3, characterized in that: The connecting tab is welded to the tab assembly and forms a weld mark on the second surface. The weld mark includes a welding protrusion protruding from the second surface. The height of the welding protrusion is less than the thickness of the second colloid.

10. The battery cell according to any one of claims 1 to 5, characterized in that: The tab body comprises a first straight section and a first bent section, the first straight section is connected to the cell body, the first straight section is connected to the first bent section and is arranged at an angle to the first bent section; The connecting tab comprises a second straight section and a second bent section arranged at an angle to the second straight section, the second bent section is arranged opposite to the first bent section, and the tab glue stripping area and the connecting area are both located in the second bent section; The maximum distance of the tab assembly in the second direction is smaller than the maximum distance of the cell body in the second direction, wherein the second direction is the thickness direction of the cell body.

11. A battery, characterized in that: The invention comprises the battery cell described in any one of claims 1 to 10.

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