Battery and battery pack

Abstract

A battery and a battery pack. The battery comprises a casing (1), electrode assemblies (2), a top cover sheet (3), terminal posts (4), first limiting members (5) and second limiting members (6), wherein the terminal posts (4) pass through terminal post holes (30), and each comprise a first post portion (40), a second post portion (41) and a third post portion (42); the first limiting members (5) are connected to the top cover sheet (3); the first post portions (40) pass through the first limiting members (5); the second limiting members (6) are connected to the top cover sheet (3); the third post portions (42) pass through the second limiting members (6); the first limiting members (5) and the second limiting members (6) clamp the second post portions (41); each first limiting member (5) has a first surface (500) and a second surface (510) in a second direction; each terminal post hole (30) has a hole wall (300); and the minimum distance between the first surface (500) and the hole wall (300) is a mm, and the minimum distance between the second surface (510) and the hole wall (300) is b mm, satisfying 0.4≤a / b≤1.5.

Description

Battery and battery pack

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on February 4, 2024, with application number 202410157148.X and application name “A Battery and Battery Pack”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to, but is not limited to, the field of battery technology, and specifically to a battery and a battery pack. Background Art

[0003] The batteries in a battery pack are usually welded to their respective poles through a busbar to form a series-parallel connection between the batteries. The busbar and the poles themselves have flatness issues. When the two ends of the busbar are welded to the poles respectively, a pulling force will be generated between the poles and the busbar due to the flatness.

[0004] Furthermore, once the battery pack is installed in a vehicle, it expands during charge and discharge cycles. During this expansion, the busbar exerts downward pressure on the terminal. Conversely, when the battery is no longer cycling, it contracts, and the busbar also exerts upward tension on the terminal. Therefore, to ensure safe and normal use of the battery under these operating conditions, it is particularly important that the terminal possesses certain tensile and compressive mechanical properties. Technical Solutions

[0005] An embodiment of the present application provides a battery; an embodiment of the present application also provides a battery pack using the above-mentioned battery.

[0006] The battery according to an embodiment of the present application has a first direction and a second direction intersecting with each other, and includes:

[0007] a housing, the housing comprising a receiving cavity and an opening communicating with the receiving cavity;

[0008] an electrode assembly, the electrode assembly being disposed in the accommodating cavity;

[0009] a top cover sheet, the top cover sheet being arranged to cover the opening, the top cover sheet being provided with a pole hole, the pole hole penetrating the top cover sheet in the first direction;

[0010] An electrode, wherein the electrode portion is passed through the electrode hole, the electrode comprising a first column portion, a second column portion, and a third column portion arranged in a first direction, the first column portion being located on a side of the third column portion away from the electrode assembly, and the second column portion being connected between the first column portion and the third column portion;

[0011] a first limiting member, the first limiting member being connected to a side of the top cover sheet facing away from the electrode assembly, the first column portion being passed through the first limiting member;

[0012] a second limiting member connected to a side of the top cover sheet facing the electrode assembly, the third column portion passing through the second limiting member, and the first limiting member and the second limiting member jointly clamping the second column portion;

[0013] In which, the first limiting member has a first surface close to the first column portion and a second surface away from the first column portion in the second direction, the pole hole has a hole wall, the minimum distance between the first surface and the hole wall in the second direction is a mm, and the minimum distance between the second surface and the hole wall in the second direction is b mm, satisfying: 0.4≤a / b≤1.5.

[0014] Optionally, the battery further satisfies: 0.43≤a / b≤1;

[0015] Optionally, the battery further satisfies: 0.96≤a≤5, 2≤b≤5.6.

[0016] Optionally, the first limiting member includes a first limiting portion and a second limiting portion connected to each other, wherein the second limiting portion surrounds the first limiting portion, the second limiting portion is connected to the top cover sheet, the first column portion passes through the first limiting portion, the first surface is located on a side of the first limiting portion facing away from the second limiting portion, and the second surface is located on a side of the second limiting portion facing away from the first limiting portion;

[0017] The second limiting member includes a third limiting portion and a fourth limiting portion that are interconnected, and the fourth limiting portion surrounds the third limiting portion, the fourth limiting portion is connected to the top cover piece, the third column portion is passed through the third limiting portion, and the second column portion is at least partially located between the first limiting portion and the third limiting portion along the first direction.

[0018] Optionally, a ring groove is formed on a side of the top cover sheet facing away from the electrode assembly, the ring groove surrounds the pole hole and is in communication with the pole hole, and the second limiting portion is embedded in the ring groove.

[0019] Optionally, the battery further includes:

[0020] A first insulating member, wherein the first insulating member includes a first insulating portion, a second insulating portion, and a third insulating portion arranged in a first direction, and the first insulating portion is located on a side of the third insulating portion away from the electrode assembly, the first limiting portion surrounds the second insulating portion, and the first insulating portion and the third insulating portion clamp the first limiting portion.

[0021] Optionally, the first limiting portion and the second limiting portion are an integrated structure.

[0022] Optionally, the second limiting member and the top cover piece are an integral structure.

[0023] Optionally, the first limiting portion opens a limiting hole in the first direction, and the first insulating member further includes a through portion connected between the first insulating portion and the third insulating portion, the through portion and the second insulating portion are spaced apart, and the through portion is arranged in the limiting hole.

[0024] Optionally, there are multiple limiting holes and multiple through-holes respectively, and the limiting holes and the through-holes correspond to each other one by one.

[0025] Optionally, one of the first insulating member and the pole is provided with a protrusion, and the other is provided with a groove for the protrusion to be embedded in.

[0026] Optionally, there are multiple protrusions and multiple grooves respectively, and the protrusions and the grooves correspond one to one.

[0027] Optionally, the battery further includes:

[0028] A sealing member, comprising a first sealing portion and a second sealing portion connected to each other, wherein the first sealing portion is arranged between the second column portion and the third limiting portion, and the first sealing portion abuts the second column portion and the third limiting portion, and the second sealing portion is arranged between the third limiting portion and the third column portion, and the second sealing portion abuts the third limiting portion and the third column portion.

[0029] Optionally, the battery further includes:

[0030] a connector, the connector comprising a pole connecting portion, a tab connecting portion, and a transition portion, the transition portion being located between the pole connecting portion and the tab connecting portion and connecting the pole connecting portion and the tab connecting portion, respectively, the transition portion being bent relative to the pole connecting portion in a direction away from the electrode assembly;

[0031] The electrode assembly includes a tab, the pole connecting portion is connected to the pole, and the tab connecting portion is connected to the tab.

[0032] Optionally, the battery further includes:

[0033] a connector, the connector comprising a pole connecting portion, a first pole tab connecting portion, a second pole tab connecting portion, and a transition portion, wherein the first pole tab connecting portion and the second pole tab connecting portion are respectively provided on opposite sides of the pole connecting portion, the transition portions are respectively connected between the pole connecting portion and the first pole tab connecting portion and the second pole tab connecting portion, and the transition portions are bent relative to the pole connecting portion in a direction away from the electrode assembly;

[0034] There are multiple electrode assemblies, each of which includes a pole lug. The pole column connecting portion is connected to the pole column, and the pole column connecting portion is located between the pole lugs of adjacent electrode assemblies. The first pole lug connecting portion is connected to the pole lug of one electrode assembly, and the second pole lug connecting portion is connected to the pole lug of another electrode assembly.

[0035] Optionally, there is a minimum spacing H mm between the tab connection portion and the pole connection portion in the first direction, and the thickness of the pole connection portion is T mm, satisfying: H>T.

[0036] Optionally, the transition portion and the pole connecting portion form an angle f that satisfies: 90°≤f≤180°.

[0037] Accordingly, a battery pack described in an embodiment of the present application includes the above-mentioned battery. Beneficial effects

[0038] The battery of the embodiment of the present application includes a shell, an electrode assembly, a top cover sheet, a pole, a first stopper, and a second stopper. The shell has a receiving cavity and an opening connected to the receiving cavity, the electrode assembly is disposed in the receiving cavity, and the top cover sheet is disposed over the opening. The top cover sheet is provided with a pole hole, which passes through the top cover sheet in a first direction, and the pole portion is disposed in the pole hole. The pole includes a first column portion, a second column portion, and a third column portion disposed in the first direction, the first column portion being located on the side of the third column portion facing away from the electrode assembly, and the second column portion being connected between the first column portion and the third column portion. A first stopper is connected to the side of the top cover sheet facing away from the electrode assembly, with the first post portion extending through the first stopper. A second stopper is connected to the side of the top cover sheet facing the electrode assembly, with the third post portion extending through the second stopper. The first stopper and the second stopper jointly clamp the second post portion. The first stopper has a first surface proximal to the first post portion and a second surface distal to the first post portion in the second direction. The terminal hole has a hole wall. The minimum distance between the first surface and the hole wall in the second direction is a mm, and the minimum distance between the second surface and the hole wall in the second direction is b mm, satisfying the following: 0.4 ≤ a / b ≤ 1.5. The first and second stoppers relatively clamp the terminal to form a limiting effect, thereby improving the tensile and compressive strength of the terminal in the first direction. Furthermore, by controlling the ratio of the dimension of the first stopper extending beyond the hole wall in the second direction to the dimension of the connection portion of the first stopper with the top cover sheet in the second direction to be between 0.4 and 1.5, it is further advantageous to ensure that the first stopper provides good tensile strength for the terminal in the first direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0040] FIG1 is a schematic structural diagram of a battery according to an embodiment of the present application;

[0041] FIG2 is a schematic diagram of the explosion structure of a battery according to an embodiment of the present application;

[0042] FIG3 is a schematic diagram of the structure of the top cover plate viewed from above according to an embodiment of the present application;

[0043] FIG4 is a cross-sectional view taken along line AA in FIG3 ;

[0044] FIG5 is an enlarged view of portion B in FIG4 ;

[0045] FIG6 is a partial cross-sectional view of the top cover sheet according to an embodiment of the present application;

[0046] FIG7 is a schematic diagram of the exploded structure of the top cover sheet, the pole, the first limiter and the first insulating member according to an embodiment of the present application;

[0047] FIG8 is a schematic structural diagram of a side view of a housing according to an embodiment of the present application;

[0048] FIG9 is a cross-sectional view taken along line CC in FIG8 ;

[0049] FIG10 is a schematic structural diagram of a connector according to an embodiment of the present application;

[0050] FIG11 is a schematic diagram of the connection structure of a tab and a connector according to another embodiment of the present application;

[0051] FIG12 is a schematic structural diagram of a connector according to another embodiment of the present invention;

[0052] FIG13 is a schematic structural diagram of another embodiment of the present invention, viewed from the side of the connecting member;

[0053] Figure numerals: 1, shell; 10, accommodating cavity; 11, opening; 2, electrode assembly; 20, winding core; 21, pole ear; 3, top cover plate; 30, pole hole; 300, hole wall; 31, ring groove; 32, pressure relief hole; 33, pressure relief valve; 34, protective sheet; 35, sealing member; 350, first sealing portion; 351, second sealing portion; 4, pole; 40, first column; 400, first annular surface; 41, second column; 410, second annular surface; 42, third column; 420, third annular surface; 43, central axis; 44, groove; 5, first limiting member; 50, first limiting portion; 5 00, first surface; 51, second limiting portion; 510, second surface; 52, limiting hole; 6, second limiting member; 60, third limiting portion; 600, third surface; 61, fourth limiting portion; 7, first insulating member; 70, first through hole; 71, first insulating portion; 72, second insulating portion; 73, third insulating portion; 74, through portion; 75, protrusion; 8, second insulating member; 80, second through hole; 9, connecting member; 90, pole connecting portion; 91, tab connecting portion; 92, transition portion; 93, first tab connecting portion; 94, second tab connecting portion; X, first direction; Y, second direction.

[0054] Implementation Methods of the Application

[0055] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0056] In the description of the present application, it should be understood that the terms "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships 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 cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "multiple" means two or more, and at least one means one, two or more, unless otherwise clearly and specifically defined.

[0057] The applicant notes that the battery's top cover is typically assembled using riveting, welding, and injection molding. The battery's poles are key components that electrically connect the electrode assembly to external devices. During battery manufacturing, the poles are typically riveted to the battery's top cover and welded to the conductive terminals. Furthermore, an upper plastic injection molding is required around the poles to provide insulation and secure support. When batteries are grouped together to form a battery pack, a busbar is typically welded to the poles of each battery to achieve series and parallel connection.

[0058] Due to the flatness problem between the busbar and each pole, when the two ends of the busbar are welded to the pole, a pulling force will be generated between the pole and the busbar due to the flatness. This pulling force may be a pressure or a tension on the pole.

[0059] Furthermore, once the battery pack is installed in a vehicle, it expands during charge and discharge cycles. During this expansion, the busbar exerts downward pressure on the terminal. Conversely, when the battery is no longer discharged, it contracts, and the busbar also exerts upward tension on the terminal. Therefore, ensuring that the terminal has good tensile and compressive strength is a key factor in ensuring battery safety.

[0060] In view of this, in conjunction with Figures 1 to 13, an embodiment of the present application provides a battery, aiming to overcome at least one of the above technical problems.

[0061] In the following embodiments, a first direction X and a second direction Y intersecting each other are introduced, wherein the first direction X is parallel to the thickness direction of the battery top cover structure in this embodiment, and the second direction Y is parallel to the length direction of the battery top cover structure in this embodiment.

[0062] 1 to 13 , a battery includes a housing 1 , an electrode assembly 2 , a top cover 3 , a terminal post 4 , a first stopper 5 , and a second stopper 6 .

[0063] The housing 1 has a housing cavity 10 and an opening 11 communicating with the housing cavity 10. The electrode assembly 2 is disposed in the housing cavity 10, and the top cover 3 covers the opening 11. The top cover 3 defines a pole hole 30, which extends through the top cover 3 in a first direction X. The pole 4 is partially disposed in the pole hole 30. The pole 4 includes a first column portion 40, a second column portion 41, and a third column portion 42 disposed in the first direction X. The first column portion 40 is located on the side of the third column portion 42 facing away from the electrode assembly 2, and the second column portion 41 is connected between the first column portion 40 and the third column portion 42.

[0064] The first stopper 5 is connected to the side of the top cover 3 facing away from the electrode assembly 2, and the first column 40 is disposed through the first stopper 5; the second stopper 6 is connected to the side of the top cover 3 facing the electrode assembly 2, and the third column 42 is disposed through the second stopper 6. The first stopper 5 and the second stopper 6 jointly clamp the second column 41;

[0065] In which, the first limit member 5 has a first surface 500 close to the first column portion 40 and a second surface 510 away from the first column portion 40 in the second direction Y, the pole hole 30 has a hole wall 300, the minimum distance between the first surface 500 and the hole wall 300 in the second direction Y is a mm, and the minimum distance between the second surface 510 and the hole wall 300 in the second direction Y is b mm, satisfying: 0.4≤a / b≤1.5.

[0066] The first stopper 5 and the second stopper 6 relatively clamp the terminal 4 in the first direction X, thereby limiting the terminal 4 and improving the tensile and compressive strengths of the terminal 4 in the first direction X. Furthermore, by controlling the ratio of the minimum distance between the first surface 500 and the hole wall 300 in the second direction Y (i.e., the dimension of the first stopper 5 extending from the hole wall 300 in the second direction Y) to the minimum distance between the second surface 510 and the hole wall 300 in the second direction Y (i.e., the dimension of the connection portion between the first stopper 5 and the top cover plate 3 in the second direction Y) to be between 0.4 and 1.5, it is helpful to further ensure that the first stopper 5 provides good tensile strength for the terminal 4 in the first direction X.

[0067] Specifically, a / b may be 0.4, 1.5, or any one of 0.4 to 1.5, or a range consisting of any two of the values.

[0068] Specifically, referring to Figures 2 to 7, in some embodiments, the first limiting member 5 includes a first limiting portion 50 and a second limiting portion 51 that are connected to each other, and the second limiting portion 51 surrounds the first limiting portion 50. The second limiting portion 51 is connected to the top cover sheet 3, the first column portion 40 is passed through the first limiting portion 50, the first surface 500 is located on a side of the first limiting portion 50 away from the second limiting portion 51, and the second surface 510 is located on a side of the second limiting portion 51 away from the first limiting portion 50;

[0069] The second limiting member 6 includes a third limiting portion 60 and a fourth limiting portion 61 that are connected to each other, and the fourth limiting portion 61 surrounds the third limiting portion 60. The fourth limiting portion 61 is connected to the top cover piece 3. The third column portion 42 is passed through the third limiting portion 60. The second column portion 41 is at least partially located between the first limiting portion 50 and the third limiting portion 60 along the first direction X.

[0070] The first limiting portion 50 and the third limiting portion 60 clamp the second column portion 41 in the first direction X, thereby improving the tensile and compressive strengths of the entire pole 4 .

[0071] Specifically, in some embodiments, referring to Figures 2 to 7 , an annular groove 31 is defined on the side of the top cover sheet 3 facing away from the electrode assembly 2. The annular groove 31 surrounds and communicates with the electrode hole 30. A second stopper 51 is connected to the top cover sheet 3 and surrounds the electrode hole 30. The second stopper 51 is embedded in the annular groove 31.

[0072] The first limiting portion 50 and the second limiting portion 51 can be an integrated structure, and the annular groove 31 provides a limiting installation function for the first limiting member 5, preventing the first limiting member 5 from increasing the thickness of the overall top cover plate 3 in the first direction X, thereby avoiding affecting the overall size of the battery.

[0073] It should be noted that during the assembly process, the first limiting member 5, the first insulating member 7 and the pole 4 can be pre-assembled and combined to form an integrated structure. The pole 4 can be quickly fixed by embedding the second limiting member 51 into the annular groove 31 and welding the top cover plate 3, which is conducive to simplifying the installation steps and improving the battery assembly efficiency.

[0074] In addition, it can be understood that compared with the structure without the annular groove 31 and the first limit member 5 is directly welded to the surface of the top cover plate 3, the annular groove 31 structure can reduce the size of the pole 4 extending out of the top cover plate 3 away from the side of the accommodating cavity 10 in the first direction X, thereby reducing the size of the overall battery in the first direction X, which is conducive to improving space utilization.

[0075] Specifically, referring to Figures 2 to 7, the third limiting portion 60 extends in the first direction X, and one end of the third limiting portion 60 in the first direction X is connected to the top cover piece 3, and the other end is connected to the fourth limiting portion 61. In some embodiments, referring to Figure 6, the second limiting member 6 as a whole can be integrally formed with the top cover piece 3.

[0076] 2 , 5 and 7 , the pole 4 has a central axis 43 , which passes through the center of the pole hole 30 in the first direction X.

[0077] In some embodiments, referring to Figures 5 and 7, the first column portion 40, the second column portion 41 and the third column portion 42 can be made of the same material such as aluminum as an integral part. In other embodiments, the first column portion 40, the second column portion 41 and the third column portion 42 can also be made of different materials. For example, the first column portion 40 and the second column portion 41 can be made of aluminum, and the third column portion 42 can be made of copper to better conduct electricity and connect the electrode assembly 2.

[0078] In some embodiments, the battery further includes a first insulating member 7 and a second insulating member 8 .

[0079] The first insulating member 7 is partially inserted into the terminal hole 30 and surrounds the terminal 4, so that the first insulating member 7 is partially in contact between the top cover 3 and the terminal 4. The second insulating member 8 is provided on the side of the top cover 3 facing the electrode assembly 2 and covers the second stopper 6. The second insulating member 8 has a second through hole 80 for the terminal 4 to pass through.

[0080] In some embodiments, referring to Figures 2, 5, and 7, the first insulating member 7 has a first through-hole 70 for the electrode column 4 to pass through. The first insulating member 7 includes a first insulating portion 71, a second insulating portion 72, and a third insulating portion 73 arranged in the first direction X, and the first insulating portion 71 is located on the side of the third insulating portion 73 facing away from the electrode assembly 2. The first limiting member 5 surrounds the second insulating portion 72, and the first insulating portion 71 and the third insulating portion 73 clamp the first limiting member 5. In this embodiment, the first insulating portion 71 and the second insulating portion 72 are both located on the side of the second column portion 41 facing away from the third column portion 42 and surround the first column portion 40. A portion of the third insulating portion 73 surrounds the first column portion 40, and another portion surrounds the second column portion 41.

[0081] In some embodiments, referring to FIG. 5 and FIG. 7 , the first limiting portion 50 defines a limiting hole 52 in the first direction X. In this embodiment, there are multiple limiting holes 52 , and the multiple limiting holes 52 are evenly distributed around the central axis 43 .

[0082] Correspondingly, the first insulating member 7 further includes a through portion 74 connected between the first insulating portion 71 and the third insulating portion 73. In this embodiment, the through portions 74 correspond one-to-one to the limiting holes 52, the through portions 74 are spaced apart from the second insulating portion 72, and the through portions 74 are disposed through the limiting holes 52. Having multiple through portions 74 disposed through corresponding limiting holes 52 further strengthens the connection stability between the first insulating member 7 and the first limiting member 5, thereby indirectly improving the torsional strength of the pole 4.

[0083] In addition, in order to further improve the torsional strength of the pole 4 , in some embodiments, one of the first insulating member 7 and the pole 4 is provided with a protrusion 75 , and the other is provided with a groove 44 for the protrusion 75 to be embedded in.

[0084] Specifically, referring to Figures 5 and 7 , in this embodiment, the protrusion 75 is provided on the side of the third insulating portion 73 facing away from the first insulating portion 71, and the groove 44 is provided on the side of the second post portion 41 facing away from the third post portion 42. Multiple protrusions 75 are provided, and the multiple protrusions 75 are evenly spaced around the central axis 43. By embedding the multiple protrusions 75 in the corresponding grooves 44, the connection stability between the pole 4 and the first insulating member 7 is further enhanced, thereby improving the torsional strength of the pole 4.

[0085] In addition, it is understandable that, in other embodiments, the plurality of protrusions 75 may also be provided on the second column portion 41 , and correspondingly, the plurality of grooves 44 may be provided on the third insulating portion 73 , which will not be further described here.

[0086] In some embodiments, referring to FIG. 5 and FIG. 7 , in order to improve the sealing effect at the pole hole 30 , the battery further includes a sealing member 35 surrounding the third pole portion 42 .

[0087] Specifically, the seal 35 includes a first sealing portion 350 and a second sealing portion 351 that are connected to each other. The first sealing portion 350 is disposed between the second column portion 41 and the third limiting portion 60, and the first sealing portion 350 abuts the second column portion 41 and the third limiting portion 60. The second sealing portion 351 is disposed between the third limiting portion 60 and the third column portion 42, and the second sealing portion 351 abuts the third limiting portion 60 and the third column portion 42.

[0088] A multi-stage seal is formed between the pole 4 and the second stopper 6 by the first sealing portion 350 and the second sealing portion 351 , thereby improving the sealing effect at the pole hole 30 and enhancing the safety of battery use.

[0089] In some embodiments, referring to Figures 2, 9, and 10, the battery further includes a connector 9. The connector 9 includes a pole connecting portion 90, a first tab connecting portion 93, a second tab connecting portion 94, and a transition portion 92. The first tab connecting portion 93 and the second tab connecting portion 94 are respectively provided on opposite sides of the pole connecting portion 90. Transition portions 92 are respectively connected between the pole connecting portion 90 and the first tab connecting portion 93 and the second tab connecting portion 94. The transition portions 92 are bent relative to the pole connecting portion 90 in a direction away from the electrode assembly 2.

[0090] Similarly, the electrode assembly 2 includes a winding core 20 and a tab 21 disposed on the side of the winding core 20 facing the electrode 4. Taking two electrode assemblies 2 as an example, the pole connecting portion 90 is opposite and conductively connected to the electrode 4 in the first direction X, and the pole connecting portion 90 is located between the tabs 21 of adjacent electrode assemblies 2. The first tab connecting portion 93 is connected to the tab 21 of one electrode assembly 2, and the second tab connecting portion 94 is connected to the tab 21 of another electrode assembly 2. Specifically, the pole connecting portion 90 and the electrode 4 can be laser welded, and the first tab connecting portion 93 and the tab 21, and the second tab connecting portion 94 and the tab 21 can be ultrasonically welded.

[0091] It is understandable that when the number of electrode assemblies 2 is greater than two, the sizes of the first tab connecting portion 93 and the second tab connecting portion 94 can be further extended to accommodate the arrangement range of the respective tabs 21 .

[0092] In some embodiments, referring to Figures 2 and 11 to 13, the connector 9 includes a pole connecting portion 90, a tab connecting portion 91, and a transition portion 92. The transition portion 92 is located between the pole connecting portion 90 and the tab connecting portion 91 and connects the pole connecting portion 90 and the tab connecting portion 91, respectively. The transition portion 92 is bent relative to the pole connecting portion 90 in a direction away from the electrode assembly 2.

[0093] 11 , the pole 4 faces the pole connection portion 90 in the first direction X, the tab 21 faces the tab connection portion 91 in the first direction X, and the pole connection portion 90 is connected to the pole 4 , and the tab connection portion 91 is connected to the tab 21 .

[0094] As shown in FIG11 , the assembly process of the electrode assembly 2 and the electrode post 4 is illustrated, for example, with the positive and negative electrode posts 4 of the battery and two electrode assemblies 2 disposed within the accommodating cavity 10. A single tab connection 91 can simultaneously connect the tabs 21 of the two electrode assemblies 2. The tab connection 91 and the electrode post connection 90 are arranged in the second direction Y. After welding the tab connection 91, the electrode post 4, and the tab 21, the two winding cores 20 need to be aligned and joined together, which will not be described in detail here.

[0095] It can be understood that a height difference is formed between the pole connection portion 90 and the tab connection portion 91 in the first direction X. Referring to Figures 10, 12 and 13, there is a minimum spacing H mm between the tab connection portion 91 and the pole connection portion 90 in the first direction X, and the thickness of the pole connection portion 90 is T mm, satisfying: H>T.

[0096] In addition, the transition portion 92 and the pole connecting portion 90 form an included angle f, which in this embodiment satisfies: 90°≤f≤180°, and optionally, 120°≤f≤150°.

[0097] The pole connecting portion 90 and the tab connecting portion 91 with a height difference reserve sufficient extension space for the pole 4 and the tab 21 , thereby avoiding affecting the internal space of the accommodating cavity 10 and reducing the risk of the tab 21 being inserted into the winding core 20 .

[0098] In some embodiments, the battery further satisfies: 0.43≤a / b≤1.

[0099] Specifically, a / b may be 0.43 or 1 or any one of 0.43 to 1 or a range consisting of any two of them.

[0100] In some embodiments, the battery may further satisfy: 0.96≤a≤5, 2≤b≤5.6.

[0101] Specifically, a can be 0.96 or 5 or any one of 0.96 to 5 or a range consisting of any two of them.

[0102] b can be 2, 5.6, or any one of 2 to 5.6, or a range of any two.

[0103] It should be noted that, structurally, referring to Figure 5, in terms of tensile resistance, the second limiting portion 51 actually serves as a fixed end connecting the top cover piece 3, that is, the value of b can reflect the actual welding area between the first limiting member 5 and the top cover piece 3, and the first limiting portion 50 actually serves as a force arm that bears the direct tensile force, that is, the value of a can reflect the size of the tensile force arm acting on the first limiting member 5.

[0104] It can be understood that when the value of a is too large, it directly leads to an increase in the force arm, and then the overall tensile strength decreases. When the value of a is too small, the first limiting portion 50 cannot provide sufficient limiting size, which will also reduce the tensile effect of the overall first limiting member 5.

[0105] Similarly, when the value of b is too large, the overall battery size will be too large, resulting in a waste of space. When the value of b is too small, the overall first limiter 5 lacks sufficient welding contact area with the top cover plate 3, resulting in a decrease in the tensile strength of the overall first limiter 5.

[0106] Hereinafter, the present application will compare the test results and evaluate the performance of Examples 1 to 6 and Comparative Examples 1 to 5:

[0107] In the provided Examples 1 to 6, 0.4≤a / b≤1.5, 0.96≤a≤5, and 2≤b≤5.6 are satisfied.

[0108] The tensile strength test method for terminal 4 is as follows: After the busbar is welded to terminal 4, the busbar is secured with a fixture. The end of the fixture, away from the busbar, is connected to a tensile testing machine. The tensile testing machine pulls the fixture to apply tension to the busbar. The busbar transmits the tension to the surface of terminal 4 through the weld marks, simulating the tensile force transmitted by the busbar to terminal 4 during system assembly and under conditions such as vehicle vibration and impact. The tensile testing machine continuously applies tension until terminal 4 breaks off and fails, and the tensile force is recorded.

[0109] In addition, this application also introduces the overcurrent capacity of pole 4 as a reference. It should be noted that during the battery charging and discharging process, the internal resistance of the battery will cause heat to be generated inside the battery. The maximum temperature of the battery is strongly related to the cycle life. Under normal circumstances, in order to ensure the number of cycles of battery service life, the maximum temperature of the battery should be ≤50℃. While ensuring that the battery temperature does not exceed 50℃, it is particularly important to improve the overcurrent capacity of the battery structural components as much as possible.

[0110] Because the previous test changed the size of the first limiter 5 in the second direction Y, the radial size of the pole 4 that needed to be adapted changed. Therefore, this test also introduced a test method for the overcurrent capacity of the pole 4: for pole 4 diameters with different gradients, an overcurrent temperature rise simulation was performed, continuously increasing the battery overcurrent value until the battery temperature reached 50°C. The overcurrent value at this time (i.e., the overcurrent limit) was recorded. It can be understood that the larger the overcurrent limit, the better the overcurrent performance of the pole 4 of that size.

[0111] The experimental conditions of Comparative Examples 1 to 5 are substantially the same as those of Example 1, except that:

[0112] Comparative Example 1: a / b>1.5, a>5, 2≤b≤5.6;

[0113] In comparative example 2, a / b < 0.4, a < 0.96, 2 ≤ b ≤ 5.6;

[0114] Comparative Example 3: a / b < 0.4, 0.96 ≤ a ≤ 5, b > 5.6;

[0115] Comparative Example 4: a / b>1.5, 0.96≤a≤5, b<2;

[0116] In comparative example 5, a / b < 0.4, a < 0.96, b < 2;

[0117] The reference comparison is as follows:

[0118]

[0119] Results analysis shows that:

[0120] With reference to Examples 1 to 3 and Comparative Examples 1 and 2, taking b=2.4, when 0.4≤a / b≤1.5 is satisfied, the pole 4 maintains a relatively high tensile performance. It should be noted that in Example 3, when a / b is 0.4, the tensile performance of the pole 4 decreases, but the pole 4 in Example 3 still maintains a tensile capacity of more than 1000N, and the overcurrent extreme value of the pole 4 in Example 3 is higher than that in Examples 1 and 2, and has good comprehensive performance.

[0121] When a / b>1.5 or a / b<0.4, the tensile strength of the pole 4 is lower than that when 0.4≤a / b≤1.5 is satisfied. The tensile strength values ​​in Comparative Examples 1 to 5 are all reduced to below 1000N.

[0122] In addition, referring to Examples 4 to 6 and Comparative Examples 3 to 5, when Examples 4 to 6 satisfy 0.4≤a / b≤1.5, the tensile strength of the pole 4 is higher than the tensile strength of the pole 4 when a / b>1.5 or a / b<0.4, and when a / b>1.5 or a / b<0.4, regardless of whether the values ​​of a and b satisfy 0.96≤a≤5 and 2≤b≤5.6, they cannot reach the tensile strength level when 0.4≤a / b≤1.5 is satisfied.

[0123] Therefore, from the comparison of the above test parameter value ranges and the tensile force results, it can be seen that when 0.4≤a / b≤1.5, 0.96≤a≤5 and 2≤b≤5.6 are satisfied, the tensile strength of the pole 4 is higher.

[0124] Accordingly, embodiments of the present application provide a battery pack comprising the aforementioned battery. The battery pack can be applied to electronic devices, power storage devices, or electric vehicles, among other devices. It is understood that the battery pack can possess all the technical features and corresponding beneficial effects of the aforementioned batteries, and further details are omitted here.

[0125] The above is a detailed introduction to a battery and a battery pack provided in the embodiments of the present application, and specific examples are used to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application; ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and 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 embodiments of the present application.

Claims

1. A battery, wherein: The battery has a first direction and a second direction intersecting each other, and the battery comprises: a housing, the housing comprising a receiving cavity and an opening communicating with the receiving cavity; an electrode assembly, the electrode assembly being disposed in the accommodating cavity; a top cover sheet, the top cover sheet being arranged to cover the opening, the top cover sheet being provided with a pole hole, the pole hole penetrating the top cover sheet in the first direction; An electrode, wherein the electrode portion is passed through the electrode hole, the electrode comprising a first column portion, a second column portion, and a third column portion arranged in a first direction, the first column portion being located on a side of the third column portion away from the electrode assembly, and the second column portion being connected between the first column portion and the third column portion; a first limiting member, the first limiting member being connected to a side of the top cover sheet facing away from the electrode assembly, the first column portion being passed through the first limiting member; a second limiting member connected to a side of the top cover sheet facing the electrode assembly, the third column portion passing through the second limiting member, and the first limiting member and the second limiting member jointly clamping the second column portion; In which, the first limiting member has a first surface close to the first column portion and a second surface away from the first column portion in the second direction, the pole hole has a hole wall, the minimum distance between the first surface and the hole wall in the second direction is a mm, and the minimum distance between the second surface and the hole wall in the second direction is b mm, satisfying: 0.4≤a / b≤1.

5.

2. The battery according to claim 1, wherein The battery further satisfies: 0.43≤a / b≤1.

3. The battery according to claim 1, wherein The battery further satisfies: 0.96≤a≤5, 2≤b≤5.

6.

4. The battery according to claim 1, wherein The first limiting member includes a first limiting portion and a second limiting portion connected to each other, wherein the second limiting portion surrounds the first limiting portion, the second limiting portion is connected to the top cover plate, the first column portion is passed through the first limiting portion, the first surface is located on a side of the first limiting portion facing away from the second limiting portion, and the second surface is located on a side of the second limiting portion facing away from the first limiting portion; The second limiting member includes a third limiting portion and a fourth limiting portion that are interconnected, and the fourth limiting portion surrounds the third limiting portion, the fourth limiting portion is connected to the top cover piece, the third column portion is passed through the third limiting portion, and the second column portion is at least partially located between the first limiting portion and the third limiting portion along the first direction.

5. The battery according to claim 4, wherein A ring groove is formed on a side of the top cover sheet facing away from the electrode assembly. The ring groove surrounds the pole hole and is in communication with the pole hole. The second limiting portion is embedded in the ring groove.

6. The battery according to claim 4, wherein Also includes: A first insulating member, wherein the first insulating member includes a first insulating portion, a second insulating portion, and a third insulating portion arranged in a first direction, and the first insulating portion is located on a side of the third insulating portion away from the electrode assembly, the first limiting portion surrounds the second insulating portion, and the first insulating portion and the third insulating portion clamp the first limiting portion.

7. The battery according to claim 4, wherein The first limiting portion and the second limiting portion are an integrated structure.

8. The battery according to claim 4, wherein The second limiting member and the top cover sheet are an integral structure.

9. The battery according to claim 6, wherein The first limiting portion defines a limiting hole in a first direction, and the first insulating member further includes a through portion connected between the first insulating portion and the third insulating portion, the through portion is spaced apart from the second insulating portion, and the through portion passes through the limiting hole.

10. The battery according to claim 9, wherein There are a plurality of the limiting holes and the through-holes, respectively, and the limiting holes and the through-holes correspond to each other one by one.

11. The battery according to claim 6, wherein One of the first insulating member and the pole is provided with a protrusion, and the other is provided with a groove for the protrusion to be embedded in.

12. The battery according to claim 11, wherein There are a plurality of convex portions and a plurality of concave portions, respectively, and the convex portions and the concave portions correspond to each other one by one.

13. The battery according to claim 4, wherein Also includes: A sealing member, comprising a first sealing portion and a second sealing portion connected to each other, wherein the first sealing portion is arranged between the second column portion and the third limiting portion, and the first sealing portion abuts the second column portion and the third limiting portion, and the second sealing portion is arranged between the third limiting portion and the third column portion, and the second sealing portion abuts the third limiting portion and the third column portion.

14. The battery according to claim 1, wherein Also includes: a connector, the connector comprising a pole connecting portion, a tab connecting portion, and a transition portion, the transition portion being located between the pole connecting portion and the tab connecting portion and connecting the pole connecting portion and the tab connecting portion, respectively, the transition portion being bent relative to the pole connecting portion in a direction away from the electrode assembly; The electrode assembly includes a tab, the pole connecting portion is connected to the pole, and the tab connecting portion is connected to the tab.

15. The battery according to claim 1, wherein Also includes: a connector, the connector comprising a pole connecting portion, a first pole tab connecting portion, a second pole tab connecting portion, and a transition portion, wherein the first pole tab connecting portion and the second pole tab connecting portion are respectively provided on opposite sides of the pole connecting portion, the transition portions are respectively connected between the pole connecting portion and the first pole tab connecting portion and the second pole tab connecting portion, and the transition portions are bent relative to the pole connecting portion in a direction away from the electrode assembly; There are multiple electrode assemblies, each of which includes a pole lug. The pole column connecting portion is connected to the pole column, and the pole column connecting portion is located between the pole lugs of adjacent electrode assemblies. The first pole lug connecting portion is connected to the pole lug of one electrode assembly, and the second pole lug connecting portion is connected to the pole lug of another electrode assembly.

16. The battery according to claim 14 or 15, wherein There is a minimum spacing H mm between the tab connection portion and the pole connection portion in the first direction, and a thickness of the pole connection portion is T mm, satisfying: H>T.

17. The battery according to claim 14 or 15, wherein The transition portion and the pole connecting portion form an included angle f, which satisfies: 90°≤f≤180°.

18. A battery pack comprising the battery according to any one of claims 1 to 17.

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