Connecting sheet and battery cell

Abstract

The utility model provides a connecting piece and a battery cell. The connecting piece comprises a body on which a mounting part is formed, and the mounting part is used for connecting a pole; the pins are arranged on the body in a bendable manner and are used for connecting the tabs; the fixing structure is arranged on the body in a bendable mode, the fixing structure and the installation part are arranged at intervals, and the fixing structure is used for being fixed by external force in the pin bending process. When the connecting piece is connected with the electrode assembly, different parts of the body can be fixed by utilizing the mounting part and the holding structure, so that the body is not easy to tilt up in a pin bending process, the difficulty of deformation and displacement of the body is increased, the body is not easy to extrude the electrode assembly, and the risk of damage to the electrode assembly is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a connecting piece and a battery cell. BACKGROUND

[0002] The connecting piece is an electrically conductive structure for electrically connecting an electrode assembly (also referred to as a core pack) and a pole in a battery cell. The connecting piece provided in the related art includes a body and a pin connected to a side edge of the body. By abutting the body against the electrode pole and welding the tab of the electrode assembly on the pin, the electrode pole and the tab of the electrode assembly are electrically connected. In order to facilitate the electrode assembly to be installed into the shell of the battery cell, the pin with the welded tab also needs to be bent so that the pin is parallel or substantially parallel to the body. However, in the process of bending the pin, the body is also easily deformed or displaced to press the electrode assembly, causing damage to the electrode assembly. CONTENT OF THE UTILITY MODEL

[0003] Embodiments of the present application provide a connecting piece and a battery cell, which can reduce the technical problem of damage to the electrode assembly caused by the body in the process of bending the pin of the connecting piece.

[0004] In a first aspect, embodiments of the present application provide a connecting piece, comprising:

[0005] a body, wherein the body is provided with a mounting portion for connecting a pole;

[0006] a pin, wherein the pin is bendably arranged on the body and used for connecting a tab;

[0007] a holding structure, wherein the holding structure is bendably arranged on the body and spaced apart from the mounting portion, and the holding structure is used for being fixed by an external force in the process of bending the pin.

[0008] In an embodiment, the body includes opposite first and second end portions, the holding structure is arranged on the second end portion, and the mounting portion is formed on the first end portion.

[0009] In an embodiment, a root portion of the holding structure is formed as a deformation portion that can be bent and deformed.

[0010] In an embodiment, the deformation portion is formed by thinning the root portion of the holding structure.

[0011] In an embodiment, a ratio of an average thickness of the deformation portion to an average thickness of the holding structure is P1, and 0.01≤P1<1.

[0012] In an embodiment, the average thickness of the deformation portion is 0.1mm-2mm; and / or, the average thickness of the holding structure is 0.1mm-3mm.

[0013] In an embodiment, when the included angle between the second end portion and the holding structure is 180°, the ratio of the length L3 of the deformation portion to the length L2 of the holding structure is P2 in the direction from the second end portion to the holding structure, and 0.01≤P2<1.

[0014] In an embodiment, the length L3 of the deformation portion is 0.1mm-4mm; and / or, the length L2 of the holding structure is 2mm-10mm.

[0015] In an embodiment, the body further comprises an intermediate portion connected between the first end portion and the second end portion, and the pin is connected to the side of the intermediate portion.

[0016] In an embodiment, the ratio of the width of the holding structure to the width of the first end portion is 0.1-1.0; and / or, when the included angle between the second end portion and the holding structure is 180°, the total length L1 of the second end portion and the holding structure in the direction from the second end portion to the holding structure is 0.1mm-30mm, and the length of the second end portion is greater than the length of the holding structure.

[0017] In an embodiment, the connecting piece is a metal piece, and the body, the pin and the holding structure are integrally formed.

[0018] In a second aspect, embodiments of the present application provide a battery monomer, comprising a pole, an electrode assembly and the connecting piece described above, the electrode assembly comprising a tab, the pin being connected to the tab, the mounting portion being connected to the pole, and the holding structure being removed or retained; the included angle between the holding structure and the second end portion is 0°-10° or 170°-180°.

[0019] In an embodiment, the battery monomer further comprises a shell and a cover, the shell having an opening and a receiving cavity in communication with the opening, the cover being arranged on the shell and closing the opening, the electrode assembly and the connecting piece being located in the receiving cavity, the connecting piece being attached to the surface of the electrode assembly, and the pole being arranged through the cover.

[0020] The beneficial effects of embodiments of the present application are as follows:

[0021] In the embodiments of this application, the connecting piece includes a body, pins, and a retaining structure. A mounting portion is formed on the body, and the retaining structure is bendable and spaced apart from the mounting portion. The pins are bendable and disposed on the body. When using the connecting piece, the body of the connecting piece is placed close to the electrode assembly. The pins are connected to the tabs of the electrode assembly, and the mounting portion is used to connect to the electrode post. That is, a part of the body can be fixed by the electrode post through the mounting portion. The retaining structure is fixed by external force, that is, another part of the body can be fixed by the retaining structure. The pins disposed on the body are bent. During the bending process, the pins will pull on the body 1. Since different parts (i.e. different locations) of the body are fixed, the body is not easy to lift up, and the difficulty of deformation and displacement of the body is increased. Thus, the body is not easy to squeeze the electrode assembly that is close to it, thereby reducing the risk of damage to the electrode assembly. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the main structure of the connecting piece provided in an embodiment of this application;

[0024] Figure 2 This is a right-side view of the connecting piece provided in an embodiment of this application;

[0025] Figure 3 yes Figure 2 Enlarged view of section A;

[0026] Figure 4 This is a cross-sectional structural diagram of a battery cell provided in an embodiment of this application;

[0027] Figure 5 This is a schematic diagram of the assembly of the electrode assembly and the cover plate in a battery cell provided in an embodiment of this application;

[0028] Figure 6 This is a schematic diagram of the assembly of the electrode assembly, cover plate and connecting piece in a battery cell provided in the embodiments of this application. Figure 1 ;

[0029] Figure 7 yes Figure 6 A three-dimensional structural diagram of the connecting piece;

[0030] Figure 8 This is a schematic diagram of the assembly of the electrode assembly, cover plate and connecting piece in a battery cell provided in the embodiments of this application. Figure 2 ;

[0031] Figure 9 is Figure 8 a perspective view of the connecting piece in the battery cell;

[0032] Figure 10 is an assembly schematic of the electrode assembly, the cover plate and the connecting piece in the battery cell provided by the embodiment of the present application Figure 3 ;

[0033] Figure 11 is Figure 10 a perspective view of the connecting piece in the battery cell;

[0034] Figure 12 is an assembly schematic of the electrode assembly, the cover plate and the connecting piece in the battery cell provided by the embodiment of the present application Figure 4 ;

[0035] Figure 13 is Figure 12 a sectional view of B-B direction in the battery cell;

[0036] Figure 14 is Figure 13 an enlarged view of C part in the battery cell;

[0037] Figure 15 is an assembly schematic of the electrode assembly, the cover plate and the connecting piece in the battery cell provided by the embodiment of the present application Figure 5 ;

[0038] Figure 16 is Figure 15 a perspective view of the connecting piece in the battery cell.

[0039] Reference signs:

[0040] 10, connecting piece;

[0041] 1, body;

[0042] 11, first end part; 111, mounting part;

[0043] 12, second end part;

[0044] 13, middle part;

[0045] 2, pin;

[0046] 3, holding structure; 3a, deformation part;

[0047] 100, battery cell;

[0048] 20, pole;

[0049] 30, electrode assembly; 301, pole tab; 40, shell; 401, accommodating cavity;

[0050] 50. The cover. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0052] In addition, it should be understood that the specific implementations described herein are merely given as illustrations of specific embodiments and do not purport to be exhaustive or to limit the application in its application to the closed forms disclosed. The various embodiments described here are not meant to be limiting in any way. In the present application, the positional words such as "upper" and "lower" generally refer to the upper and lower in the actual use or working state of the device, and specifically refer to the direction of the drawing surface in the drawings, unless otherwise specified. "Inner" and "outer" are relative to the outline of the device.

[0053] The terms "first", "second", etc. are used only for the purpose of description and should not be understood as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0054] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood in a broad sense, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected or can communicate with each other; can be directly connected, or indirectly connected through an intermediate medium; can be the internal connection of two elements or the interaction relationship between two elements. For a person of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0055] The term "comprising" or "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or apparatus including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such a process, method, article or apparatus. Without more limitations, the element defined by the sentence "including a" does not exclude the presence of other identical elements in the process, method, article or apparatus including the element.

[0056] In the description of the embodiments of the present application, the words "example" or "for example" or similar words are used to represent examples, illustrations, or descriptions. Any embodiment or design scheme described as "example" or "for example" in the embodiments of the present application is not interpreted as more preferred or having more advantages than another embodiment or design scheme. The words "example" or "for example" or similar words are intended to present relative concepts in a clear manner.

[0057] In order to facilitate the understanding of the scheme of the present application, the spline curves and arrows used in the reference signs in the drawings are described as follows: the components indicated by the spline curves without arrows are solid components, i.e., components with solid structures; and the components indicated by the spline curves with arrows are virtual components, i.e., components without solid structures.

[0058] In order to solve the problem that the body is easily pressed against the electrode assembly in the process of bending the pin of the connecting piece, causing damage to the electrode assembly, the embodiments of the present application provide a solution, which fixes the body in the process of bending the pin to prevent the body from deforming or displacing, thereby reducing the risk of the body pressing against the electrode assembly and causing damage to the electrode assembly.

[0059] In order to fix the body, the embodiments of the present application improve the structure of the connecting piece.

[0060] In the first aspect, referring to Figures 1 to 16 The embodiments of the present application provide a connecting piece 10, which comprises a body 1, a pin 2, and a holding structure 3. The body 1 is provided with a mounting portion 111 for connecting a pole 20; the pin 2 is bendably arranged on the body 1 and is used for connecting a tab 301; and the holding structure 3 is bendably arranged on the body 1 and is spaced apart from the mounting portion 111, and the holding structure 3 is used for being fixed by an external force in the process of bending the pin 2.

[0061] Specifically, the connecting piece 10 is a conductive structure, and the connecting piece 10 is used for connecting the pole 20 and the tab 301 of the electrode assembly 30, so as to realize the connection between the electrode assembly 30 and an external circuit. As an example, the connecting piece 10 is a metal piece, i.e., the material of the connecting piece 10 is metal. The metal not only has conductivity, but also has toughness and ductility, so that it is convenient to bend part of the structure of the connecting piece 10, such as the pin 2.

[0062] The electrode assembly 30 can also be referred to as a jelly-roll, and the electrode assembly 30 is an important component of the battery cell 100 (also referred to as a battery cell). The electrode assembly 30 includes stacked separators and electrode sheets, i.e., the separators and the electrode sheets are stacked. In detail, in terms of the electrode sheets, the electrode sheets include positive electrode sheets and negative electrode sheets, and the positive electrode sheets, the negative electrode sheets, and the separators are stacked, with the separators being located between the positive electrode sheets and the negative electrode sheets to separate the positive electrode sheets and the negative electrode sheets and prevent the positive electrode sheets and the negative electrode sheets from directly contacting each other and causing a short circuit. The number of the separators in the electrode assembly 30 can be one or more, the number of the positive electrode sheets can be one or more, and the number of the negative electrode sheets can be one or more. The electrode assembly 30 can be a stacked structure or a wound structure.

[0063] The tab 301 is connected to the electrode sheet. In detail, in terms of structure, the electrode sheet includes a current collector and an active material layer, and the active material layer is disposed on the current collector, which can be disposed on one side of the current collector or on both sides of the current collector. The tab 301 is connected to the current collector. As an example, the tab 301 and the current collector are integrally formed, or the tab 301 and the current collector are separately formed and then connected together, such as being welded together.

[0064] For the positive electrode sheet, the current collector is a positive current collector, and the active material layer is a positive active material layer. As an example, the positive current collector can be an aluminum foil or a carbon-coated aluminum foil; the thickness of the positive current collector can be 5 μm to 20 μm, such as 5 μm, 10 μm, 15 μm, or 20 μm. The active material layer contains an active material, and for the positive active material layer, the positive active material layer contains a positive active material. As an example, the positive active material includes at least one of nickel-cobalt-manganese ternary material (NMC), lithium cobaltate (LiCoO2), lithium iron phosphate (LiFePO4, LFP), lithium manganate (LiMn2O4, LMO), and nickel-cobalt-aluminum lithium (NCA).

[0065] For the negative electrode sheet, the current collector is a negative current collector, and the active material layer is a negative active material layer. As an example, the negative current collector can be a copper foil, and the thickness of the copper foil can be 4 μm to 7 μm, such as 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, or 7 μm. The active material layer contains an active material, and for the negative active material layer, the negative active material layer contains a negative active material. As an example, the negative active material includes at least one of graphite, graphene, carbon nanotubes, and silicon-based materials.

[0066] It can be understood that the tab 301 is connected to the current collector, which can be the positive current collector or the negative current collector.

[0067] The connecting tab 10 comprises a body 1, a pin 2 and a holding structure 3, the pin 2 and the holding structure 3 are connected with the body 1 respectively, wherein the body 1 is used for connecting with the pole 20, and the pin 2 is used for connecting with the tab 301. As an example, in the charging state, the current can flow through the pole 20, the body 1, the pin 2, the tab 301 and the current collector in turn; in the discharging state, the current can flow through the current collector, the tab 301, the pin 2, the body 1 and the pole 20 in turn.

[0068] The body 1 is provided with a mounting portion 111, and the body 1 can be connected with the pole 20 through the mounting portion 111. The mounting portion 111 can have different forms. As an example, the mounting portion 111 is a mounting hole, which is used for sleeving on the pole 20 and being welded together with the pole 20. As an example, the mounting portion 111 is a mounting groove, one end of the pole 20 is inserted into the mounting groove, and the end face of the pole 20 is welded together with the inner wall face of the mounting groove. As an example, the mounting portion 111 is a mounting sheet, one end of the pole 20 is supported on the mounting sheet, and the end face of the pole 20 is welded together with the supporting face of the mounting sheet.

[0069] The pin 2 is connected with the body 1, specifically, the pin 2 is foldably arranged on the body 1, that is, the pin 2 can be folded relative to the body 1. In this way, the size of the included angle between the pin 2 and the body 1 can be adjusted by folding the pin 2. Here, the included angle between the pin 2 and the body 1 refers to the included angle between the surface of the pin 2 and the surface of the body 1, and the size of the included angle is between 0° and 180°.

[0070] As an example, when the pin 2 is in the unfolded state, the included angle between the pin 2 and the body 1 is the largest, and the included angle between the pin 2 and the body 1 is 180° or close to 180°; by folding the pin 2, the included angle between the pin 2 and the body 1 becomes smaller, and the pin 2 enters the protruding state (see Figure 7 ), the free end of the pin 2 protrudes from the side face of the body 1; in the protruding state, the included angle between the pin 2 and the body 1 is less than 180° but greater than 0°; for example, the pin 2 is perpendicular to the body 1, at this time, the included angle between the pin 2 and the body 1 is 90° or close to 90°, the closer the included angle between the pin 2 and the body 1 is to 90°, the higher the height of the free end of the pin 2 protruding from the side face of the body 1 is; by continuing to fold the pin 2, the pin 2 and the body 1 can be folded together, that is, the pin 2 enters the folded flat state (see Figure 9 ); in the folded flat state, the included angle between the pin 2 and the body 1 is 0° or close to 0°, and the pin 2 is parallel or substantially parallel to the body 1. It should be noted that by forward folding the pin 2, the pin 2 can enter the protruding state from the unfolded state and / or enter the folded flat state from the protruding state; by reverse folding the pin 2, the pin 2 can enter the protruding state from the folded flat state and / or enter the unfolded state from the protruding state.

[0071] Optionally, the pin 2 is arranged on a side edge of the body 1. Generally, the body 1 has opposite two ends corresponding to the first end 11 and the second end 12 respectively, and the body 1 also has opposite two side edges, which are the edge portions of the body 1 and can extend from the first end 11 to the second end 12. The pin 2 is arranged on a side edge of the body 1. It should be noted that the pin 2 can be arranged on one side edge of the body 1 or arranged on both side edges of the body 1. The number of the pin 2 in the connecting piece 10 can be one or more. Here, more refers to at least two. For example, the number of the pin 2 is one, that is, one pin 2 is arranged on one side edge of the body 1. For example, the number of the pin 2 is two, that is, one pin 2 is arranged on each of the two side edges of the body 1. For example, the number of the pin 2 is four, that is, two pins 2 are arranged on each of the two side edges of the body 1.

[0072] The pin 2 is used to connect the tab 301. For example, the pin 2 is used to be welded with the tab 301. For example, the pin 2 and the tab 301 can be welded together by laser welding or ultrasonic welding.

[0073] Before the pin 2 connects the tab 301, the body 1 of the connecting piece 10 is arranged close to the electrode assembly 30, for example, the body 1 is attached to one side of the electrode assembly 30, so as to shorten the distance between the pin 2 and the tab 301.

[0074] When the pin 2 is connected with the tab 301, the included angle between the pin 2 and the body 1 can be first adjusted to be greater than 0° and less than 180°, that is, the pin 2 is in a convex state, which is convenient for operation; after the pin 2 is connected with the tab 301 (that is, the connecting piece 10 is connected with the electrode assembly 30), the included angle between the pin 2 and the body 1 is adjusted to be equal to or close to 0°, that is, the pin 2 is in a flat state, or the included angle between the pin 2 and the body 1 is adjusted to be equal to or close to 180°, that is, the pin 2 is in an expanded state, so that the pin 2 is closer to the electrode assembly 30 as a whole, which can reduce the risk of interference between the pin 2 and the shell 40 of the battery monomer 100 when the connected connecting piece 10 and the electrode assembly 30 are loaded into the shell 40, and can also reduce the occupation of the pin 2 to the accommodation space in the shell 40.

[0075] For example, when the pin 2 is in the flat state, the tab 301 is located on the side of the pin 2 away from the body 1; or when the pin 2 is in the expanded state, the tab 301 is located on the side of the pin 2 close to the electrode assembly 30.

[0076] The holding structure 3 is connected with the body 1, specifically, the holding structure 3 is foldably arranged on the body 1, that is, the holding structure 3 can be folded relative to the body 1. As an example, the connecting piece 10 is a metal piece, and the material of the holding structure 3 is metal. The toughness and ductility of metal can make the holding structure 3 easy to be folded. In addition, metal also has mechanical strength, which can ensure the strength of the connection between the holding structure 3 and the body 1.

[0077] The holding structure 3 is used to be fixed by external force in the process of bending the pin 2. Here, the external force refers to the force exerted by an object other than the connecting piece 10 on the holding structure 3. Alternatively, a jig is used to cooperate with the holding structure 3 in the process of bending the pin 2, and the jig is used to exert force on the holding structure 3 to fix the holding structure 3. The cooperation between the jig and the holding structure 3 includes but is not limited to at least one of clamping, inserting, clamping and sleeving. As an example, the jig includes a clamp, which clamps the holding structure 3 to fix the holding structure 3.

[0078] Since the holding structure 3 can be folded, as the holding structure 3 is folded, the angle between the holding structure 3 and the body 1 changes. Here, the angle between the holding structure 3 and the body 1 refers to the angle between the surface of the holding structure 3 and the surface of the body 1, and the size of the angle is between 0° and 180°.

[0079] In detail, when the holding structure 3 is in the flat state, the angle between the holding structure 3 and the body 1 is equal to or close to 180° (see Figure 11 ), the extension direction of the holding structure 3 is consistent with the extension direction of the body 1; as the holding structure 3 is folded, the holding structure 3 enters the convex state, and the free end of the holding structure 3 protrudes from the side surface of the body 1; in the convex state, the angle between the holding structure 3 and the body 1 is less than 180° but greater than 0° (see Figure 9 ), for example, the angle between the holding structure 3 and the body 1 is 90°, at which time the holding structure 3 and the body 1 are perpendicular to each other; generally, the closer the angle between the holding structure 3 and the body 1 is to 90°, the higher the height of the free end of the holding structure 3 protruding from the side surface of the body 1, which is more conducive to exerting external force on the holding structure 3 to fix it; by continuing to fold the holding structure 3, the holding structure 3 and the body 1 can be folded together, that is, the holding structure 3 enters the flat-folded state; in the flat-folded state, the angle between the holding structure 3 and the body 1 is 0° or close to 0°, at which time the holding structure 3 is parallel or substantially parallel to the body 1. It should be noted that by folding the holding structure 3 in the forward direction, the holding structure 3 can enter the convex state from the flat state and / or enter the flat-folded state from the convex state; by folding the holding structure 3 in the reverse direction, the holding structure 3 can enter the convex state from the flat-folded state and / or enter the flat state from the convex state.

[0080] In the process of connecting the pin 2 with the tab 301, the angle between the holding structure 3 and the body 1 can be first adjusted to be greater than 0° and less than 180°, that is, the holding structure 3 is in a convex state, which facilitates the fixation of the holding structure 3; after the holding structure 3 is fixed, if the pin 2 is not in a convex state, the pin 2 is bent so that the pin 2 is in a convex state; then the pin 2 is connected with the tab 301; the pin 2 is bent again so that the pin 2 changes from the convex state to the flat state or the flat state; then the angle between the holding structure 3 and the body 1 is adjusted to be equal to 0° or close to 0°, that is, the holding structure 3 is in a flat state; or the angle between the holding structure 3 and the body 1 is adjusted to be equal to 180° or close to 180°, that is, the holding structure 3 is in a flat state; or the holding structure 3 is separated from the body 1 (see Figure 15 and Figure 16 ); in this way, when the connected sheet 10 and the electrode assembly 30 are loaded into the shell 40 together, the risk of interference between the holding structure 3 and the shell 40 of the battery monomer 100 is reduced, and in addition, the occupation of the holding structure 3 in the accommodation space of the shell 40 is reduced.

[0081] As an example, in the case where the material of the holding structure 3 is metal, the holding structure 3 can be bent to cause metal fatigue fracture, so that the holding structure 3 is separated from the body 1.

[0082] As an example, the holding structure 3 can be sheared to cause the holding structure 3 to break, so that the holding structure 3 is separated from the body 1.

[0083] In summary, by arranging the holding structure 3 to be bendable on the body 1, not only the fixation of the holding structure 3 is facilitated, but also the risk of interference between the holding structure 3 and the shell 40 of the battery monomer 100 is reduced, and the occupation of the holding structure 3 in the accommodation space of the shell 40 is reduced.

[0084] In addition, when the holding structure 3 is arranged on the body 1, the holding structure 3 is kept spaced apart from the mounting portion 111. That is, the holding structure 3 and the mounting portion 111 are located on different parts of the body 1, so that when the mounting portion 111 is connected with the pole 20 and the holding structure 3 is also fixed by an external force, different parts of the body 1 can be fixed, so that the degree of freedom of displacement of the body 1 is reduced. The distance between the holding structure 3 and the mounting portion 111 can be set according to requirements. Usually, the holding structure 3 is also spaced apart from the pin 2.

[0085] The connecting piece 10 provided by the embodiment of the present application comprises a body 1, a pin 2 and a holding structure 3. The body 1 is provided with a mounting portion 111. The holding structure 3 is arranged on the body 1 and spaced from the mounting portion 111. The pin 2 is arranged on the body 1. In use, the body 1 of the connecting piece 10 is arranged close to the electrode assembly 30. The pin 2 is connected with the tab 301 of the electrode assembly 30. The mounting portion 111 is connected with the pole 20. That is, a part of the body 1 is fixed by the pole 20 through the mounting portion 111. The holding structure 3 is fixed by external force, that is, another part of the body 1 is fixed by the holding structure 3. The pin 2 arranged on the body 1 is bent. During the bending process, the pin 2 pulls the body 1. Since different parts of the body 1 are fixed, the body 1 is not easy to be warped. The difficulty of deformation and displacement of the body 1 is increased. Thus, the body 1 is not easy to press the electrode assembly 30 close to it, thereby reducing the risk of damage to the electrode assembly 30.

[0086] In some embodiments, the body 1 comprises a first end portion 11 and a second end portion 12. The first end portion 11 is arranged opposite to the second end portion 12. The mounting portion 111 is formed on the first end portion 11. The holding structure 3 is arranged on the second end portion 12. It can be found that when the mounting portion 111 is connected with the pole 20 and the holding structure 3 is fixed by external force, the first end portion 11 and the second end portion 12 can be fixed, that is, the opposite ends of the body 1 are fixed. The difficulty of deformation and displacement of the body 1 is increased. Thus, the body 1 is not easy to press the electrode assembly 30 close to it. In addition, the mounting portion 111 is located on the first end portion 11. The holding structure 3 is located on the second end portion 12. The spacing distance between the mounting portion 111 and the holding structure 3 is large. The risk of interference with each other during assembly is reduced.

[0087] Of course, in other embodiments, the holding structure 3 can be arranged between the first end portion 11 and the second end portion 12.

[0088] In some embodiments, please refer to Figure 1 , Figure 7 and Figure 9 The root of the holding structure 3 is formed as a deformation portion 3a which can be bent and deformed. The root of the holding structure 3 refers to the part directly connected with the second end portion 12. The deformation portion 3a refers to the part which can be bent and deformed. The root is the deformation portion 3a, that is, when the holding structure 3 is bent relative to the second end portion 12, the root is deformed and bent. The deformation portion 3a is a part of the holding structure 3. When the holding structure 3 is bent relative to the body 1, specifically, the deformation portion 3a is bent and deformed. By arranging the root of the holding structure 3 as the deformation portion 3a, when the deformation portion 3a is deformed, the position of the holding structure 3 as a whole can be changed.

[0089] In some embodiments, referring to Figure 1 , Figure 7 and Figure 9 , the deformation portion 3a is formed by thinning the root portion of the holding structure 3, i.e. the holding structure 3 is partially thinned to form the deformation portion 3a. It can be appreciated that the thickness of the deformation portion 3a is less than the average thickness of the holding structure 3. By setting the thickness of the deformation portion 3a to be less than the thickness of other portions of the holding structure 3, the mechanical strength of the deformation portion 3a is reduced, so that the deformation portion 3a is more likely to deform than other portions of the holding structure 3, reducing the difficulty of bending the holding structure 3, while the holding structure 3 has a good mechanical strength, so that the holding structure 3 is not easily deformed when fixed by an external force.

[0090] Of course, in other embodiments, the deformation portion 3a can also be made more likely to deform by changing the material. For example, the deformation portion 3a can be made of a metal material with a smaller hardness, while the material of other portions of the holding structure 3 is a metal material with a larger hardness. In this case, the thickness of the deformation portion 3a can be set to be less than or equal to the thickness of other portions of the holding structure 3.

[0091] In some embodiments, the thickness of the deformation portion 3a is less than the average thickness of the body 1. In this way, the body 1 and the holding structure 3 can define a groove corresponding to the deformation portion 3a. When the deformation portion 3a is provided, the root portion can be thinned as a whole, so that one groove is formed; or the root portion can be partially thinned, so that one or more grooves are formed.

[0092] In some embodiments, the ratio of the average thickness of the deformation portion 3a to the average thickness of the holding structure 3 is P1, and 0.01≤P1<1. In this range, the holding structure 3 is relatively low in difficulty of bending relative to the body 1, reducing the assembly difficulty. As an example, P1 is 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9. Alternatively, 0.2≤P1≤0.6, in this range, the holding structure 3 has good deformation ability and mechanical strength.

[0093] In some embodiments, the average thickness of the deformation portion 3a is 0.1mm-2mm. Generally, the greater the average thickness of the deformation portion 3a, the higher the mechanical strength of the deformation portion 3a but the lower the deformation ability, and the smaller the average thickness of the deformation portion 3a, the lower the mechanical strength of the deformation portion 3a but the higher the deformation ability. By setting the average thickness of the deformation portion 3a to be 0.1mm-2mm, the deformation portion 3a can have both good deformation ability and mechanical strength, and the risk of the deformation portion 3a breaking can be reduced. For example, the average thickness of the deformation portion 3a is 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm or 2.0mm.

[0094] In some embodiments, the average thickness of the body 1 is 1mm-2mm, which can make the connecting tab 10 have good mechanical strength and improve the deformation resistance of the connecting tab 10. For example, the average thickness of the body 1 is 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm or 2.0mm.

[0095] In some embodiments, the average thickness of the pin 2 is 1mm-2mm. For example, the average thickness of the pin 2 is 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm or 2.0mm.

[0096] In some embodiments, the average thickness of the body 1 is equal to the average thickness of the pin 2, which is convenient for manufacturing.

[0097] In some embodiments, the average thickness of the body 1 is greater than the average thickness of the pin 2. Generally, the pin 2 is connected with the tab 301, specifically, the pin 2 is welded with the tab 301 by laser welding or ultrasonic welding. Since the thickness of the tab 301 is small, the thickness of the pin 2 should not be too large, otherwise the welding difficulty will increase. The thickness of the body 1 should not be too small, otherwise the flow capacity of the connecting tab 10 will be affected. By setting the average thickness of the body 1 to be greater than the average thickness of the pin 2, the flow capacity of the body 1 can be improved, and the welding difficulty between the pin 2 and the tab 301 can be reduced.

[0098] In some embodiments, the average thickness of the holding structure 3 is 0.1mm-3mm. In this range, the holding structure 3 can have good mechanical strength, and the risk of deformation of the connecting tab 10 can be reduced. For example, the average thickness of the holding structure 3 is 0.1mm, 0.5mm, 0.8mm, 1.0mm, 1.2mm, 1.5mm, 1.8mm, 2.0mm, 2.2mm, 2.5mm, 2.8mm or 3mm.

[0099] In some embodiments, please refer to Figure 1The body 1 further comprises a middle part 13, which is connected between the first end part 11 and the second end part 12, i.e. the first end part 11, the middle part 13 and the second end part 12 are connected in sequence. The pin 2 is connected with the body 1, specifically, the pin 2 is connected with the side of the middle part 13. It can be understood that the first end part 11, the second end part 12 and the pin 2 are located at different positions of the middle part 13. In this way, the risk of interference with other structures can be reduced when the pin 2 is bent. The holding structure 3 is connected with the second end part 12, i.e. the holding structure 3 is indirectly connected with the middle part 13 through the second end part 12.

[0100] In some embodiments, referring to Figure 1 , the ratio of the width W1 of the holding structure 3 to the width W2 of the first end part 11 is 0.1-1.0. That is, the width W1 of the holding structure 3 can be less than or equal to the width W2 of the first end part 11. If the width W1 of the holding structure 3 is too large, the volume and mass burden of the connecting piece 10 will be increased, but if the width W1 of the holding structure 3 is too small, the fixing effect of the holding structure 3 on the body 1 will be reduced. As an example, the ratio of the width W1 of the holding structure 3 to the width W2 of the first end part 11 is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 1.0. Alternatively, the width W1 of the holding structure 3 is equal to the width of the second end part 12.

[0101] In some embodiments, referring to Figure 1 , in the case where the included angle between the second end part 12 and the holding structure 3 is 180°, i.e. the holding structure 3 is in a flat state, the extension direction of the holding structure 3 is consistent with the extension direction of the second end part 12, along the direction from the second end part 12 to the holding structure 3, the ratio of the length L3 of the deformation part 3a to the length L2 of the holding structure 3 is P2, and 0.01≤P2<1. In this range, the difficulty of bending the holding structure 3 relative to the body 1 is low, and the holding structure 3 is easy to be fixed by external force. As an example, P2 is 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9. Alternatively, 0.3≤P2≤0.7, in this range, the holding structure 3 has better deformation ability and mechanical strength.

[0102] In some embodiments, referring to Figure 1 , in the case where the included angle between the second end part 12 and the holding structure 3 is 180°, i.e. the holding structure 3 is in a flat state, the extension direction of the holding structure 3 is consistent with the extension direction of the second end part 12, along the direction from the second end part 12 to the holding structure 3, the length L3 of the deformation part 3a is 0.1mm-4mm. As an example, L3 is 0.1mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm or 4mm.

[0103] In some embodiments, referring to Figure 1 In the case that the included angle between the second end portion 12 and the holding structure 3 is 180°, i.e. the holding structure 3 is in the flat state, the extension direction of the holding structure 3 is consistent with the extension direction of the second end portion 12, and the length L2 of the holding structure 3 is 2mm-10mm in the direction from the second end portion 12 to the holding structure 3. As an example, L2 is 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm.

[0104] In some embodiments, referring to Figure 1 In the case that the included angle between the second end portion 12 and the holding structure 3 is 180°, i.e. the holding structure 3 is in the flat state, the extension direction of the holding structure 3 is consistent with the extension direction of the second end portion 12, and the total length L1 of the second end portion 12 and the holding structure 3 is 0.1mm-30mm in the direction from the second end portion 12 to the holding structure 3. As an example, L1 is 0.1mm, 1mm, 2mm, 5mm, 8mm, 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm or 30mm. Moreover, the length of the second end portion 12 is greater than the length L2 of the holding structure 3, so that the holding structure 3 can avoid the pin 2 when the holding structure 3 is in the flat state.

[0105] In some embodiments, referring to Figure 1 The first end portion 11 is connected to the middle portion 13 and is located on the first side of the middle portion 13; the pin 2 is connected to the middle portion 13, and the pin 2 is located on the second side of the middle portion 13 when the pin 2 is in the protruding state and the flat state, the first side and the second side being opposite sides of the middle portion 13. In addition, the holding structure 3 is connected to the second end portion 12, and the holding structure 3 is located on the second side of the second end portion 12 when the holding structure 3 is in the protruding state and the flat state, the second side of the second end portion 12 being the same side as the second side of the middle portion 13.

[0106] In some embodiments, the connecting piece 10 is a metal piece, and the body 1, the pin 2 and the holding structure 3 are integrally formed. By setting the connecting piece 10 as a metal piece, the metal not only has good electrical conductivity, but also has good toughness and ductility, so that the pin 2 and the holding structure 3 can be bent relative to the body 1; and the body 1, the pin 2 and the holding structure 3 are integrally formed, which enhances the strength of the connection between the pin 2 and the holding structure 3 and the body 1, and the pin 2 and the holding structure 3 are not easy to break away from the body 1 during the bending of the pin 2 and the holding structure 3.

[0107] In the second aspect, referring to Figures 4 to 16The application further provides a battery cell 100. The battery cell 100 is a basic unit for realizing mutual conversion between chemical energy and electrical energy. Specifically, the battery cell 100 comprises a pole 20, an electrode assembly 30, and the above-mentioned connecting piece 10. The electrode assembly 30 comprises a pole tab 301. The mounting portion 111 is connected to the pole 20. The pin 2 is connected to the pole tab 301. The retaining structure 3 is removed or retained.

[0108] Specifically, in the case of retaining the retaining structure 3, the retaining structure 3 can be in a flat state, and the included angle between the retaining structure 3 and the second end portion 12 is 180° or close to 180°. Alternatively, the included angle between the retaining structure 3 and the second end portion 12 is 170°-180°. As an example, the included angle between the retaining structure 3 and the second end portion 12 is 170°, 171°, 172°, 173°, 174°, 175°, 176°, 177°, 178°, 179°, or 180°.

[0109] Specifically, in the case of retaining the retaining structure 3, the retaining structure 3 can be in a flat state, and the included angle between the retaining structure 3 and the second end portion 12 is 180° or close to 180°. Alternatively, the included angle between the retaining structure 3 and the second end portion 12 is 170°-180°. As an example, the included angle between the retaining structure 3 and the second end portion 12 is 170°, 171°, 172°, 173°, 174°, 175°, 176°, 177°, 178°, 179°, or 180°.

[0110] In some embodiments, the battery cell 100 further comprises a shell 40. The shell 40 has an opening and a receiving cavity 401, and the receiving cavity 401 communicates with the opening. The electrode assembly 30 can be placed into the receiving cavity 401 through the opening, i.e., the electrode assembly 30 is located in the receiving cavity 401. The connecting piece 10 is connected to the electrode assembly 30, specifically, the connecting piece 10 is attached to the surface of the electrode assembly 30, so that the connecting piece 10 is also located in the receiving cavity 401. The shell 40 is provided to load and protect the electrode assembly 30 and the connecting piece 10. In addition, the receiving cavity 401 can also be used to load electrolyte, and the electrode assembly 30 can also be soaked in the electrolyte.

[0111] In some embodiments, the battery cell 100 further comprises a cover 50. The cover 50 is arranged on the shell 40 and closes the opening, so that the receiving cavity 401 forms a closed cavity to prevent the substances in the receiving cavity 401 from leaving the receiving cavity 401. In addition, the pole 20 is arranged on the cover 50, specifically, the pole 20 is arranged through the cover 50. One end of the pole 20 is exposed on the outer surface of the cover 50, i.e., the side surface of the cover 50 away from the shell 40. The other end of the pole 20 extends into the receiving cavity 401 and is connected to the connecting piece 10, specifically, the mounting portion 111 of the connecting piece 10.

[0112] In some embodiments, a liquid injection port (not shown) is formed on the cover 50, through which electrolyte can be injected into the accommodation cavity 401.

[0113] As an example, the assembling process of the battery cell 100 includes:

[0114] S1, the pole post 20 is arranged on the cover 50;

[0115] S2, the pin 2 and the holding structure 3 on the connecting sheet 10 are respectively bent to be perpendicular to the body 1;

[0116] S3, the pole post 20 and the mounting portion 111 on the connecting sheet 10 are connected (for example, welded) together;

[0117] S4, the cover 50 is arranged on the electrode assembly 30, and the body 1 of the connecting sheet 10 is tightly attached to the electrode assembly 30;

[0118] S5, the pin 2 on the connecting sheet 10 and the tab 301 of the electrode assembly 30 are connected (for example, welded) together;

[0119] S6, the holding structure 3 is fixed by using a jig;

[0120] S7, the pin 2 is bent again, so that the pin 2 is flattened or folded flat;

[0121] S8, the holding structure 3 is released from the jig;

[0122] S9, the holding structure 3 is bent again, so that the holding structure 3 is flattened (see Figure 10 ) or folded flat, or the holding structure 3 is removed (see Figure 15 );

[0123] S10, the connecting sheet 10 and the electrode assembly 30 connected together are loaded into the accommodation cavity 401 through the opening of the shell 40, and the cover 50 is arranged on the shell 40 to close the opening;

[0124] S11, electrolyte is injected into the accommodation cavity 401, and the battery cell 100 is obtained.

[0125] The embodiments of the present application are described in detail above, and the specific examples are applied to the principle and implementation mode of the present application. The above description of the embodiments is only used to help understand the method and core idea of the present application; meanwhile, according to the idea of the present application, the specific implementation mode and application range will be changed by the skilled in the art, and the above description of the present application should not be understood as a limitation.

Claims

1. A tab, characterized in that The application relates to a connecting piece for connecting a tab and a pole, comprising: a body, wherein a mounting portion for connecting a pole is formed on the body; a pin, which is arranged on the body and used for connecting a tab; and a holding structure, which is arranged on the body and spaced from the mounting portion, and is used for being fixed by an external force during bending of the pin. The body comprises a first end portion and a second end portion opposite to each other, the holding structure is arranged on the second end portion, and the mounting portion is formed on the first end portion. A root of the holding structure is formed as a deformation portion which can be deformed. The deformation portion is formed by thinning the root of the holding structure.

2. The tab of claim 1, wherein A ratio of an average thickness of the deformation portion to an average thickness of the holding structure is P1, and 0.01<=P1<1.

3. The tab according to claim 2, characterized in that The average thickness of the deformation portion is 0.1mm-2mm, and / or the average thickness of the holding structure is 0.1mm-3mm.

4. The tab of claim 3, wherein In a case where an included angle between the second end portion and the holding structure is 180 degrees, a ratio of a length L3 of the deformation portion to a length L2 of the holding structure in a direction from the second end portion to the holding structure is P2, and 0.01<=P2<1.

5. The tab of claim 4, wherein, The length L3 of the deformation portion is 0.1mm-4mm, and / or the length L2 of the holding structure is 2mm-10mm.

6. The tab of claim 5, wherein The body further comprises an intermediate portion connected between the first end portion and the second end portion, and the pin is connected to a side edge of the intermediate portion.

7. The tab of claim 4, wherein A ratio of a width of the holding structure to a width of the first end portion is 0.1-1.0, and / or in a case where an included angle between the second end portion and the holding structure is 180 degrees, a total length L1 of the second end portion and the holding structure in a direction from the second end portion to the holding structure is 0.1mm-30mm, and a length of the second end portion is greater than a length of the holding structure.

8. The tab of claim 7, wherein The connecting piece is a metal piece, and the body, the pin and the holding structure are integrally formed.

9. The tab according to any one of claims 2 to 8, characterized in that The battery monomer further comprises a shell and a cover, the shell has an opening and a containing cavity in communication with the opening, the cover is arranged on the shell and seals the opening, the electrode assembly and the connecting piece are located in the containing cavity, the connecting piece is attached to a surface of the electrode assembly, and the pole penetrates through the cover.

10. The tab according to any one of claims 2 to 8, characterized in that The application relates to a connecting piece for connecting a tab and a pole, comprising: a body, wherein a mounting portion for connecting a pole is formed on the body; a pin, which is arranged on the body and used for connecting a tab; and a holding structure, which is arranged on the body and spaced from the mounting portion, and is used for being fixed by an external force during bending of the pin.

11. The tab according to any one of claims 1 to 8, characterized in that ​ 12. A battery cell characterized by, ​ ​ 13. The battery cell of claim 12, wherein, ​

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