Battery monomer and preparation method thereof

Abstract

The invention relates to a battery monomer and a preparation method thereof. The battery monomer comprises an end cover, an electrode assembly, an insulating glue filling piece and heat-conducting glue, the end cover comprises a cover plate and a pole arranged on the cover plate, the electrode assembly is provided with a tab end facing the cover plate, and a tab is convexly arranged at the tab end. The insulating glue filling piece is arranged between the electrode assembly and the cover plate and is provided with a glue filling space and an avoiding hole communicated with the glue filling space, an opening is formed in the end, facing the tab end, of the insulating glue filling piece, the tab extends into the glue filling space through the opening, and the pole penetrates through the avoiding hole and is connected with the tab in the glue filling space. And the heat-conducting glue is filled in the glue filling space through the opening and wraps the tab and the pole. According to the technical scheme, the heat dissipation capability of the battery monomer is improved, and the reliability of the battery monomer is improved.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a battery cell and a method for manufacturing the same. Background Art

[0002] As the charging rate of the battery cell increases, during the charging process, the temperature inside the battery cell rises more and more seriously. The high temperature of the battery cell mainly comes from the electrode assembly inside it. The high temperature of the electrode assembly can be transmitted to the pole column through the tab, and then heat exchange is carried out with the external liquid cooling structure through the pole column. If the connection position between the pole column and the tab is unreliable, it will affect the heat dissipation of the electrode assembly and reduce the reliability of the battery cell. Summary of the Invention

[0003] Based on this, a battery cell and a method for manufacturing the same are provided, which can improve the heat dissipation ability of the battery cell and enhance its reliability.

[0004] In a first aspect, the present application provides a battery cell, comprising: An end cap, comprising a cover plate and a pole column provided on the cover plate; An electrode assembly, having a tab end facing the cover plate, and a tab protruding from the tab end; An insulating filling member, provided between the electrode assembly and the cover plate, having a filling space and an avoidance hole communicating with the filling space, one end of the insulating filling member facing the tab end is provided with an opening, the tab extends into the filling space through the opening, the pole column passes through the avoidance hole, and is connected to the tab in the filling space; and A thermal conductive adhesive, filled into the filling space through the opening, and covering the tab and the pole column.

[0005] In some embodiments, the projection of the opening along the thickness direction of the cover plate includes the projection of the tab end along the thickness direction.

[0006] In some embodiments, the pole column includes a mating section, and the mating section mates with the avoidance hole by itself or through a sealing member.

[0007] In some embodiments, the pole column includes the mating section and a welding section adjacent to and connected to the mating section, the welding section is located in the filling space and is welded to the tab; along the thickness direction of the cover plate, the projection of the welding section exceeds the projections of the mating section and the avoidance hole; The inner wall of the avoidance hole is configured to be deformable.

[0008] In some embodiments, a plurality of notches are recessed on the hole wall of the avoidance hole, and the plurality of notches are arranged at intervals along the circumferential direction of the avoidance hole; Each of the notches penetrates the wall of the insulating filler along the thickness direction, so that the inner wall of the avoidance hole can be bent and deformed.

[0009] In some embodiments, the insulating filler includes a partition strip and / or a convex post; The partition strip is located in the filling space and divides the filling space into a main space and an overflow space. The avoidance hole communicates with the main space, and the tab extends into the main space; the partition strip is formed with an overflow channel that communicates the overflow space with the main space; at least the main space is filled with the thermal conductive adhesive; A liquid injection hole is provided on the cover plate. The convex post is located in the filling space and extends toward the tab end to pass through the open end and is spaced from the tab end; a liquid injection flow channel communicating with the liquid injection hole is formed in the convex post; along the thickness direction of the cover plate, the projection of the outlet end of the liquid injection hole is within the projection range of the inlet end of the liquid injection flow channel.

[0010] In some embodiments, the battery cell further includes an insulating support member, which is disposed at the tab end and is disposed opposite to the thermal conductive adhesive; The insulating support member is provided with a hollow position penetrating along the thickness direction of the cover plate, and the hollow position is sleeved around the tab.

[0011] In some embodiments, the cover plate has an outer end face disposed away from the electrode assembly; each of the pole columns has a first current-carrying surface disposed away from the electrode assembly, and the area S1 of the first current-carrying surfaces of all the pole columns and the area S2 of the outer end face satisfy: 0.45S2 ≤ S1 < S2.

[0012] In some embodiments, each of the pole columns has a second current-carrying surface disposed opposite to the first current-carrying surface, and the area S1' of the second current-carrying surfaces of all the pole columns and the area S2 of the outer end face satisfy: 0.5S2 ≤ S1' < S2.

[0013] In some embodiments, the end cover includes N pole columns, and the N pole columns are arranged side by side and spaced apart along the length direction of the cover plate, where N ≥ 4 and is an even number.

[0014] In some embodiments, in the plane of the outer end face, the distance between the first current-carrying surfaces of adjacent pole columns is m, the distance between the first current-carrying surfaces of the head and tail pole columns and the edge of the outer end face in the length direction is p, and the distance between the first current-carrying surfaces of all the pole columns and the edge of the outer end face in the width direction is n; Satisfy: S2 = (a + 2n) * [N * b + 2p + (N - 1) * m], where m ≥ 2mm, n ≥ 4mm, p ≥ 4mm.

[0015] In some embodiments, a plurality of tab ears are configured, and the plurality of tab ears are arranged at intervals along the length direction of the cover plate. Each pole column is correspondingly welded to one tab ear, and the polarities of adjacent tab ears are opposite.

[0016] In some embodiments, in the length direction of the cover plate, the length L1 of the tab ear with negative polarity and the length L2 of the tab ear with positive polarity satisfy: L1 ≤ L2, or 0.25L2 ≤ L1 ≤ 0.9L2.

[0017] In a second aspect, the present application provides a method for preparing a battery cell, which is applied to the battery cell described in any of the above embodiments. The preparation method includes: Pass the pole column on the end cover through the avoidance hole of the insulating filling member so that the pole column extends into the filling space of the insulating filling member; Turn the open end of the insulating filling member upward, and weld the tab ear of the electrode assembly in a lying state to the pole column located in the filling space; when in the lying state, the tab ear end of the electrode assembly is located on one side of the electrode assembly in the horizontal direction; Pour the heat-conducting glue into the filling space through the open end; Bend the tab ear and turn over the electrode assembly until the tab ear end of the electrode assembly is oppositely arranged with the open end of the insulating filling member.

[0018] Compared with the prior art, the technical solution of the present application has the following beneficial effects: In the above battery cell, an insulating filling member is provided between the cover plate of the end cover and the tab ear end of the electrode assembly. The pole column and the tab ear both extend into the filling space in the insulating filling member. During the preparation of the battery cell, the heat-conducting glue is poured into the filling space through the open end of the insulating filling member, ensuring that the heat-conducting glue effectively coats the pole column and the tab ear, enhancing the connection reliability between the two, and also increasing the heat transfer area between the two to a certain extent and improving the heat transfer efficiency between the two. Moreover, the amount of the heat-conducting glue is limited by the filling space, which can reduce the consumption of the heat-conducting glue and reduce the cost. All in all, the heat dissipation ability of the battery cell proposed by the present application is improved, and its reliability is also improved.

[0019] For the method for preparing the above battery cell, the insulating caulking member is inverted with its opening facing upward, and when the electrode assembly is in a lying state, the tab is inserted into the caulking space through the opening, and welded to the pole column in the caulking space, making the welding operation of the tab and the pole column simpler and more convenient. In addition, after the tab and the pole column are welded, thermal conductive adhesive can be poured through the opening, which can ensure that the thermal conductive adhesive effectively covers the tab and the pole column, and the process of pouring the thermal conductive adhesive is easier to control. Description of the Drawings

[0020] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present application. Moreover, in all the drawings, the same reference numerals are used to represent the same components. In the drawings: Figure 1 Schematic diagrams of the outer shapes of battery cells of some embodiments are shown.

[0021] Figure 2 Shows Figure 1 Exploded schematic diagrams of the battery cells shown.

[0022] Figure 3 Shows Figure 1 Internal structural schematic diagrams of the battery cells shown.

[0023] Figure 4 Schematic diagrams of the structures of insulating caulking members of some embodiments are shown.

[0024] Figure 5 Shows Figure 3 An enlarged view of I in the figure.

[0025] Figure 6 Exploded schematic diagrams of end caps of some embodiments are shown.

[0026] Figure 7 Internal sectional views of seals of some embodiments are shown.

[0027] Figure 8 Shows Figure 4 Another perspective view of the insulating caulking member shown.

[0028] Figure 9 Shows Figure 8 An enlarged view of II in the figure.

[0029] Figure 10 Partial structural schematic diagrams of cover plates of some embodiments are shown.

[0030] Figure 11 Schematic diagrams of the structures of sealing nails of some embodiments are shown.

[0031] Figure 12 Shows a partial structural schematic diagram of an insulating caulking member in some embodiments.

[0032] Figure 13 Shows Figure 2 An enlarged schematic diagram of part III in

[0033] Figure 14 Shows a structural schematic diagram of an insulating support member in some embodiments.

[0034] Figure 15 Shows Figure 14 Another perspective view of the insulating support member shown in

[0035] Figure 16 Shows a partial structural schematic diagram of a battery cell in some embodiments.

[0036] Figure 17 Shows an exploded schematic diagram of a battery cell in some embodiments.

[0037] Figure 18 Shows Figure 17 Another perspective view of the battery cell shown in

[0038] Figure 19 Shows a structural schematic diagram of an end cap in some embodiments.

[0039] Figure 20 Shows a sectional schematic diagram of an end cap in some embodiments.

[0040] Figure 21 Shows a process schematic diagram of a preparation method of a battery cell in some embodiments.

[0041] Figure 22 Shows a schematic diagram of the state change of an electrode assembly during the preparation of a battery cell.

[0042] The reference numerals in the specific embodiments are as follows: 100, Battery cell; Z, Thickness direction; X, Length direction; Y, Width direction; 10, End cap; 11, Cover plate; 11a, Liquid injection hole; a1, Sunk groove; a2, Through hole; 11b, Terminal hole; 12, Terminal; 12b, Fitting section; 12c, Welding section; GL1, First overcurrent surface; GL2, Second overcurrent surface; 13, Sealing member; 13d, Mounting hole; 13e, First sealing groove; 13i, Second sealing groove; 14, Sealing nail; 14g, Boss portion; 14k, Column portion; W, Outer end face; T, Spacing area; 20, Electrode assembly; J, Tab end; 21, Tab; 21a, Root section; 21b, Tail section; 21c, Bending section; 30, Insulating filling rubber part; 31, Bottom plate; 32, Side plate; 30h, Filling rubber space; h1, Main space; h2, Excess rubber space; 30i, Avoidance hole; 30m, Open end; 30n, Notch; 30p, Corner position; 33, Partition bar; 33q, Excess rubber channel; 34, Convex column; 34r, Liquid injection flow channel; 40, Thermal conductive adhesive; 50, Insulating support member; 50u, Hollow position; u1, Support groove; u11, Opening; d1, First end face; d2, Second end face; 51, Reinforcing rib; 50v, Liquid passing hole; 60, Outer shell; 70, Thermal conductive coating member. Detailed implementation manners

[0043] To make the above objects, features, and advantages of the present application more apparent and understandable, the following will describe the detailed implementation manners of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description to facilitate a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0044] In the description of the present application, it should be understood that if there are terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application.

[0045] In addition, if present, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0046] In this application, unless otherwise clearly specified and limited, if present, terms such as "installed", "connected", "joined", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0047] To improve the heat dissipation of the electrode assembly, the applicant considered setting a thermal conductive adhesive between the end cap of the battery cell and the electrode assembly. On the one hand, the thermal conductive adhesive is used to coat the pole column and the pole ear to improve the connection reliability between the two. On the other hand, the thermal conductive adhesive is used to increase the heat transfer path, improve the heat dissipation effect, and reduce the temperature difference in the height direction of the battery cell. When considering the setting method of the thermal conductive adhesive, if the dispensing method is adopted (such as directly coating the thermal conductive adhesive at the connection of the pole column and the pole ear, or coating the thermal conductive adhesive on the inner side of the end cap) to coat the connection of the pole ear and the pole column with the thermal conductive adhesive, not only is the efficiency low, but also the problem of uneven distribution of the thermal conductive adhesive is likely to occur. If a glue filling hole is provided on the end cap and the thermal conductive adhesive is filled into the battery cell through the glue filling hole, a large amount of thermal conductive adhesive needs to be filled to fill all the spaces between the end cap and the electrode assembly to ensure that the thermal conductive adhesive can effectively coat the connection of the pole column and the pole ear, resulting in a high cost.

[0048] Based on this, the embodiments of this application propose a battery cell and its preparation method. By configuring an insulating filler between the end cap and the electrode assembly, the amount of the thermal conductive adhesive is limited by the filling space of the insulating filler. During the preparation of the battery cell, the thermal conductive adhesive is injected into the filling space through the opening of the insulating filler, while reducing the amount of the thermal conductive adhesive, ensuring that the thermal conductive adhesive can well coat the pole column and the pole ear, improving the heat dissipation ability of the battery cell, and further improving the reliability of the battery cell.

[0049] The battery cell in the embodiments of this application will be introduced in detail below.

[0050] Figure 1 The external shape schematic diagram of the battery cell 100 of some embodiments is shown. Figure 2 The Figure 1 exploded schematic diagram of the shown battery cell 100 is shown.Figure 3 shows Figure 1 a schematic internal structure diagram of the battery cell 100 shown.

[0051] Please refer to Figures 1 to 3 , the battery cell 100 proposed in the embodiment of the present application includes an end cover 10, an electrode assembly 20, an insulating filler 30, and a thermal conductive adhesive 40. The end cover 10 includes a cover plate 11 and a pole post 12 provided on the cover plate 11. The electrode assembly 20 has an ear end J facing the cover plate 11, and an ear 21 protrudes from the ear end J. The insulating filler 30 is provided between the electrode assembly 20 and the cover plate 11, and has a filling space 30h and an avoidance hole 30i communicating with the filling space 30h. One end of the insulating filler 30 facing the ear end J is provided with an opening 30m, and the ear 21 extends into the filling space 30h through the opening 30m. The pole post 12 passes through the avoidance hole 30i and is connected to the ear 21 in the filling space 30h. The thermal conductive adhesive 40 is filled into the filling space 30h through the opening 30m and covers the ear 21 and the pole post 12.

[0052] Specifically, the cover plate 11 of the end cover 10 covers the open end of the outer shell 60. The ear end J is located at one or both ends of the electrode assembly 20. When the ear end J is located at one end of the electrode assembly 20, a positive ear and a negative ear usually protrude therefrom. Correspondingly, the cover plate 11 covers the open end of one end of the outer shell 60. When the ear end J is located at the opposite ends of the electrode assembly 20, at least one ear 21 protrudes therefrom. Correspondingly, the cover plate 11 covers the open ends of both ends of the outer shell 60. Optionally, the battery cell 100 is a square battery, and the cover plate 11 is a square plate.

[0053] Generally, a pole post hole 11b is provided on the cover plate 11, and the pole post 12 passes through the pole post hole 11b. One end thereof extends out of the outer side of the cover plate 11 and is directly or indirectly electrically connected to an external circuit, and the other end extends out of the inner side of the cover plate 11 (the side facing the electrode assembly 20) and is connected to the ear 21. The connection manner between the pole post 12 and the ear 21 includes welding, clamping, etc.

[0054] The insulating filler 30 has insulation properties. It is arranged between the ear end J and the cover plate 11 to insulate the ear end J from the cover plate 11 and reduce the risk of electric leakage of the cover plate 11. The insulating filler 30 forms a filling space 30h, and one end thereof facing the ear end J is provided with an opening 30m. The opening 30m is an open hole / opening structure that communicates the filling space 30h with the ear end J.

[0055] One end of the terminal post 12 penetrates through the avoidance hole 30i and extends into the glue filling space 30h, and the tab 21 penetrates through the opening 30m and extends into the glue filling space 30h. The two are connected within the glue filling space 30h, and the connection part of the two is located within the glue filling space 30h. Among them, the insulating glue filling member 30 and the cover plate 11 can be assembled and connected, bonded, etc., so that the position of the insulating glue filling member 30 is fixed. Of course, other methods can be adopted to fix the position of the insulating glue filling member 30.

[0056] Figure 4 The structural schematic diagram of the insulating glue filling member 30 of some embodiments is shown. In one embodiment, referring to Figure 4 , the insulating glue filling member 30 can be formed by a bottom plate 31 and a side plate 32. The side plate 32 is arranged in a circle around the edge of the bottom plate 31. The two together form the glue filling space 30h. One end of the side plate 32 facing away from the bottom plate 31 is completely open to form the above-mentioned opening 30m. The bottom plate 31 is arranged close to the cover plate 11, and the avoidance hole 30i is located on the bottom plate 31. At this time, the structure of the insulating glue filling member 30 is simple, and the manufacturing cost can be reduced. Optionally, the shape of the bottom plate 31 generally matches the shape of the cover plate 11. For example, if the cover plate 11 is a square plate, the bottom plate 31 can also be a square plate.

[0057] In other embodiments, the insulating glue filling member 30 may further include a sealing plate (not shown). The sealing plate is arranged at one end of the side plate 32 facing away from the bottom plate 31 and is opposite to the bottom plate 31. An open hole facing the tab end J is arranged on the sealing plate, and the open hole is used as the above-mentioned opening 30m. At this time, one or more open holes can be arranged on the sealing plate, and each open hole can penetrate through one or more tabs 21 and extend into the glue filling space 30h.

[0058] Specifically, the number of the insulating glue filling members 30 can be configured as one or more. If multiple insulating glue filling members 30 are configured, different tabs 21 and different terminal posts 12 can extend into the filling spaces of each insulating glue filling member 30, that is, a set of tabs 21 and terminal posts 12 are correspondingly configured with one insulating glue filling member 30. Optionally, as Figure 2 and Figure 3 shown, only one insulating glue filling member 30 is configured, and all the tabs 21 and all the terminal posts 12 are located within the glue filling space 30h of the insulating glue filling member 30. In this way, the structure of the battery cell 100 can be simplified.

[0059] During the process of manufacturing the battery cell 100, after fixing the insulating filler member 30 (with its opening 30m facing away from the cover plate 11), the tab 21 and the terminal post 12 are fixed within the filling space 30h (such as by welding or clamping), and then flowing thermal conductive adhesive 40 is injected into the filling space 30h through the opening 30m, and the thermal conductive adhesive 40 is waited to solidify. It should be noted that the thermal conductive adhesive 40 can fill the filling space 30h and make thermal contact with the tab end J of the electrode assembly 20. The thermal conductive adhesive 40 can also only fill a part of the filling space 30h, as long as it can well cover the tab 21 and the terminal post 12.

[0060] In the above-mentioned battery cell 100, an insulating filler member 30 is provided between the cover plate 11 of the end cover 10 and the tab end J of the electrode assembly 20. Both the terminal post 12 and the tab 21 extend into the filling space 30h within the insulating filler member 30. During the manufacturing process of the battery cell 100, the thermal conductive adhesive 40 is poured into the filling space 30h through the opening 30m of the insulating filler member 30, ensuring that the thermal conductive adhesive 40 effectively covers the terminal post 12 and the tab 21, enhancing the connection reliability between the two, and also increasing the heat transfer area between the two to a certain extent, improving the heat transfer efficiency between the two, thereby reducing the temperature difference between the two. Moreover, by using the filling space 30h to limit the amount of the thermal conductive adhesive 40, the consumption of the thermal conductive adhesive 40 can be reduced and the cost can be lowered. Compared with the prior art, the heat dissipation capacity of the battery cell 100 proposed in this application is improved and its reliability is enhanced.

[0061] Generally but not limitedly, the insulating filler member 30 is in thermal connection with the cover plate 11. Specifically, the insulating filler member 30 can be directly attached to the inner side of the cover plate 11 or adhesively connected, etc. At this time, the insulating filler member 30 is set to be thermally conductive with the cover plate 11, and the heat on the tab 21 and the terminal post 12 can be transferred to the cover plate 11 through the thermal conductive adhesive 40 and the insulating filler member 30, and heat exchange is carried out between the cover plate 11 and the external liquid cooling structure, improving the heat dissipation capacity of the battery cell 100.

[0062] In order to facilitate the pouring of the thermal conductive adhesive 40, in some embodiments, when pouring the thermal conductive adhesive 40, the end where the opening 30m of the insulating filler member 30 is located is opposite and spaced from the tab end J. As for whether they are spaced after the battery cell 100 is assembled, it is not limited. For example, the tab 21 extends into the filling space 30h before being bent. At this time, the opening 30m is spaced from the tab end J. After the pouring of the thermal conductive adhesive 40 is completed, the tab 21 is bent so that the tab end J approaches the opening 30m until the tab end J closes the opening 30m.

[0063] In some embodiments, in combination with Figure 3 understanding, the projection of the opening 30m along the thickness direction Z of the cover plate 11 includes the projection of the tab end J along this thickness direction Z.

[0064] At this time, the open area of ​​the opening 30m is relatively large. When the pole tab 21 and the pole post 12 are welded, it is convenient to perform welding operations on the pole post 12 and the pole tab 21 in the glue filling space 30h, and the glue filling process can also be visualized to ensure that the thermal conductive glue 40 effectively covers the pole post 12 and the pole tab 21. Specifically, the projection of the opening 30m can exceed the projection range of the pole tab end J. Specifically, the opening 30m can be formed by the end of the side plate 32 facing away from the bottom plate 31.

[0065] Figure 5 Shown Figure 3 Enlarged view of point I in the middle.

[0066] In some embodiments, in combination Figure 5 It is understood that the pole 12 includes a matching section 12 b, and the matching section 12 b itself or through the sealing member 13 is matched with the avoidance hole 30 i.

[0067] In one example (not shown), the matching section 12b itself matches with the avoidance hole 30i, for example, a matching groove is provided on one of the two, and a matching protrusion is provided on the other to be locked in the matching groove. Figure 5 In the illustrated example, the mating section 12 b of the pole 12 is mated with the avoidance hole 30 i via the sealing member 13 .

[0068] At this time, since the matching section 12b is directly or indirectly matched with the avoidance hole 30i, the positional relationship between the two is fixed. In this way, through the matching of the matching section 12b of the pole 12 and the avoidance hole 30i, the position of the insulating filler 30 and the cover plate 11 can be fixed, and the installation of the insulating filler 30 is achieved.

[0069] In the case where the matching section 12b is matched with the avoidance hole 30i, since the insulating filler 30 can be positioned and installed by matching the matching section 12b and the avoidance hole 30i, the positioning and installation of the insulating filler 30 does not depend on the cover plate 11, so there is no limitation on whether the insulating filler 30 is thermally connected to the cover plate 11. Of course, regardless of whether the matching section 12b is matched with the avoidance hole 30i, the insulating filler 30 can also be installed by bonding, clamping, fastening, etc. with the cover plate 11.

[0070] Figure 6 An exploded schematic view of the end cap 10 is shown in accordance with some embodiments. Figure 7 An internal cross-sectional view of the seal 13 of some embodiments is shown.

[0071] In a specific embodiment, in combination Figure 5 , Figure 6 and Figure 7It is understood that the cover plate 11 includes a pole hole 11b, a seal 13 is installed in the pole hole 11b, a first sealing groove 13e is provided on the seal 13 and is concave-convexly matched with the hole wall of the pole hole 11b, the seal 13 has a mounting hole 13d, the mounting hole 13d is passed through the matching section 12b, and a second sealing groove 13i is formed on the hole wall of the mounting hole 13d and is concave-convexly matched with the matching section 12b.

[0072] The seal 13 can be made of soft materials such as silicone and rubber. The seal 13 is in a ring shape, such as a circle shape, a square ring shape, etc. The inner wall of the ring of the seal 13 encloses a mounting hole 13d, and the mounting hole 13d is set through the thickness direction Z of the cover plate 11. The seal 13 passes through the pole hole 11b, and is sealed and matched with the concave-convex structure on the hole wall of the pole hole 11b through the first sealing groove 13e. The mounting hole 13d of the seal 13 is passed through the matching section 12b of the pole 12, and the concave-convex structure on its outer wall is sealed and matched with the second sealing groove 13i.

[0073] At this time, the pole 12 and the pole hole 11b of the cover plate 11 are sealed and connected via the concave-convex seal 13. The sealing path is relatively long, which can effectively ensure the sealing performance of the connection between the pole 12 and the cover plate 11 and play an insulating effect.

[0074] Specifically, if Figure 5 As shown, the inner wall of the avoidance hole 30i of the insulating filler 30 can be matched with the hole wall of the pole hole 11b in the first sealing groove 13e.

[0075] In some embodiments, the pole 12 includes the above-mentioned matching section 12b and a welding section 12c adjacent to the matching section 12b, and the welding section 12c is located in the glue filling space 30h and is welded to the pole lug 21. Along the thickness direction Z of the cover plate 11, the projection of the welding section 12c exceeds the projection of the matching section 12b and the projection of the avoidance hole 30i. The inner wall of the avoidance hole 30i is configured to be deformable.

[0076] The projection shape of the welding section 12c, the projection shape of the matching section 12b, and the projection shape of the avoidance hole 30i are basically matched. For example, when the projection shapes of the three are all circular, the outer diameter of the welding section 12c is larger than the outer diameter of the matching section 12b, and the inner diameter of the avoidance hole 30i is smaller than the outer diameter of the welding section 12c. For another example, when the projection shapes of the three are all square, in the length direction X and the width direction Y of the square projection, the size of the welding section 12c is larger than the size of the matching section 12b and the size of the avoidance hole 30i.

[0077] The inner wall of the avoidance hole 30i is deformable, which means that the avoidance hole 30i can change shape with the action of external force to allow the welding section 12c to pass through the avoidance hole 30i. In order to realize the internal deformation of the avoidance hole 30i, the insulating filler 30 can adopt a soft structure, such as silica gel or rubber.

[0078] When assembling the battery cell 100, the insulating caulking member 30 is installed inside the end cap 10. During this process, as the insulating caulking member 30 gradually approaches the inside of the cover plate 11, the avoidance hole 30i is first caught by the welding section 12c (during this process, the avoidance hole 30i deforms under the action of the welding section 12c). After the welding section 12c passes through the avoidance hole 30i, the avoidance hole 30i reaches the position where it is mated with the mating section 12b (the avoidance hole 30i returns to its initial state).

[0079] At this time, the part of the insulating caulking member 30 where the avoidance hole 30i is located cannot escape from the welding section 12c of the pole 12 in the thickness direction Z of the cover plate 11, improving the installation stability of the insulating caulking member 30.

[0080] Figure 8 Shows Figure 4 Another perspective view of the insulating caulking member 30 shown. Figure 9 Shows Figure 8 The enlarged view at II in

[0081] Specifically in the embodiment, referring to Figure 4 、 Figure 8 And Figure 9 , a plurality of notches 30n are formed by the inner wall depression of the avoidance hole 30i, and the plurality of notches 30n are arranged at intervals along the circumferential direction of the avoidance hole 30i. Each notch 30n penetrates the wall body of the insulating caulking member 30 in the above-mentioned thickness direction Z, so that the inner wall of the avoidance hole 30i can be bent and deformed.

[0082] When assembling the battery cell 100, as the insulating caulking member 30 gradually approaches the inside of the cover plate 11, the avoidance hole 30i is caught by the welding section 12c. Due to the extrusion of the welding section 12c, the inner wall parts of the avoidance hole 30i on both sides of the notch 30n will bend towards the inside of the caulking space 30h, so that the hole structure formed by the avoidance hole 30i becomes larger, and then allows the welding section 12c to pass through the avoidance hole 30i. When the welding section 12c passes through the avoidance hole 30i, the extrusion effect of the welding section 12c disappears, and the bent part of the insulating caulking member 30 rebounds to the initial state and is successfully mated with the mating section 12b.

[0083] At this time, by arranging a plurality of notches 30n in the circumferential direction of the avoidance hole 30i, the deformability of the hole wall of the avoidance hole 30i is realized through the notches 30n to allow the welding section 12c to pass through. There is no requirement for whether the material of the insulating caulking member 30 is a flexible material, which makes the material selection range of the insulating caulking member 30 wider and can improve the overall strength of the insulating caulking member 30.

[0084] In one embodiment, as shown in Figure 4 And Figure 8As shown, the avoidance hole 30i is a square hole, and the notch 30n is arranged at the corner position 30p of the avoidance hole 30i. At this time, the notch 30n is arranged at the corner position 30p of the avoidance hole 30i, and the inner wall of the avoidance hole 30i is more prone to bending and deformation. At the same time, when the notch 30n is restored to its original state after bending and deformation, it can avoid that the notch 30n position cannot be deformed or the notch 30n is torn and deformed and cannot be restored, which affects the sealing effect.

[0085] In some embodiments, in combination Figure 8 and Figure 9 It is understood that the insulating filler 30 includes a partition bar 33. The partition bar 33 is located in the filler space 30h and divides the filler space 30h into a main space h1 and an overflow space h2. The avoidance hole 30i is connected to the main space h1, and the tab 21 extends into the main space h1. The partition bar 33 forms an overflow channel 33q that connects the overflow space h2 with the main space h1. At least the main space h1 is filled with thermal conductive glue 40.

[0086] It can be understood that the pole 12 extends into the main space h1 after the avoidance hole 30i is penetrated, and is connected to the pole ear 21 located in the main space h1. When the insulating filler 30 is formed by the bottom plate 31 and the side plate 32, the partition bar 33 is arranged on the bottom plate 31. Specifically, the partition bar 33 can be surrounded by the filling space 30h to form an overflow space h2, and the partition bar 33 can also be spaced from the side plate 32 to form an overflow space h2.

[0087] The overflow glue channel 33q is used for storing the excess thermal conductive glue 40 in the overflow glue space h2 through the overflow glue channel 33q when the required amount of thermal conductive glue 40 in the main space h1 is reached, so as to prevent the thermal conductive glue 40 from overflowing the glue filling space 30h.

[0088] In one embodiment, the overflow glue channel 33q includes an overflow glue hole formed in the partition bar 33 itself, and the arrangement height of the overflow glue hole in the thickness direction Z of the cover plate 11 is not lower than the thickness of the thermal conductive glue 40 required in the main space h1. In another embodiment, the partition bar 33 is arranged below the end surface where the opening 30m is located (that is, the partition bar 33 is lower than the end of the side plate 32 away from the bottom plate 31), so that the overflow glue channel 33q is formed between the partition bar 33 and the end surface where the opening 30m is located. The height of the partition bar 33 determines the thickness of the thermal conductive glue 40. This method can simplify the structure of the partition bar 33.

[0089] During the potting process, thermal conductive adhesive 40 is injected into the main space h1 through the open port 30m until the thermal conductive adhesive 40 effectively wraps the tab 21 and the terminal post 12. When the required amount of thermal conductive adhesive 40 in the main space h1 is reached but the injection of the thermal conductive adhesive 40 is not stopped in time, the excess thermal conductive adhesive 40 can flow through the overflow channel 33q to the overflow space h2. In this way, not only can the overflow of the thermal conductive adhesive 40 from the potting space 30h be avoided, but also it is convenient to judge whether the potting of the thermal conductive adhesive 40 is in place and effectively control the amount of the thermal conductive adhesive 40.

[0090] In a specific embodiment, the partition strip 33 and the side wall of the potting space 30h (formed by the side plate 32) are spaced apart to form an overflow groove, and this overflow groove serves as the overflow space h2. At this time, the overflow space h2 is located in the edge area of the potting space 30h, which is convenient for arranging the tab 21 and the terminal post 12.

[0091] In some embodiments, Figure 3 and Figure 8 Understood in combination, the insulating potting member 30 includes a convex post 34. The cover plate 11 is provided with a liquid injection hole 11a. The convex post 34 is located in the potting space 30h and extends toward the tab end J through the open port 30m and is spaced from the tab end J. A liquid injection flow channel 34r communicating with the liquid injection hole 11a is formed in the convex post 34. Along the thickness direction Z of the cover plate 11, the projection of the outlet end of the liquid injection hole 11a is within the projection range of the inlet end of the liquid injection flow channel 34r.

[0092] Specifically, the bottom plate 31 is attached to the cover plate 11. A convex post 34 is protrudingly provided at a position corresponding to the liquid injection hole 11a on the bottom plate 31 toward the tab end J. The liquid injection flow channel 34r in the convex post 34 is arranged opposite to the liquid injection hole 11a. The electrolyte injected through the liquid injection hole 11a first flows through the liquid injection flow channel 34r and then infiltrates toward the tab end J of the electrode assembly 20.

[0093] Since the projection of the outlet end of the liquid injection hole 11a is within the projection range of the inlet end of the liquid injection flow channel 34r, that is, the inner diameter of the inlet end of the liquid injection flow channel 34r is larger than the inner diameter of the outlet end of the liquid injection hole 11a, the electrolyte can smoothly enter the liquid injection flow channel 34r after being discharged from the liquid injection hole 11a and will not flow out of the liquid injection flow channel 34r. Since the convex post 34 extends beyond the open port 30m, during the potting process, the thermal conductive adhesive 40 will not block the liquid injection flow channel 34r. Since the convex post 34 is spaced from the tab end J, after the electrolyte flows out of the liquid injection flow channel 34r, it can flow toward various parts of the tab end J, making the electrolyte more evenly infiltrate the electrode assembly 20.

[0094] In this way, the setting of the convex post 34 enables the electrolyte to be smoothly injected into the battery cell 100 and is conducive to realizing the uniform distribution of the electrolyte inside the electrode assembly 20.

[0095] Figure 10 Shows a partial structural schematic diagram of the cover plate 11 of some embodiments.Figure 11 Shows a schematic structural diagram of the sealing nail 14 of some embodiments. Figure 12 Shows a partial schematic structural diagram of the insulating caulking member 30 of some embodiments.

[0096] In some embodiments, referring to Figure 3 , the end cover 10 further includes a sealing nail 14 provided at the liquid injection hole 11a. The sealing nail 14 is hermetically arranged at the liquid injection hole 11a, which can prevent the free electrolyte inside the battery cell 100 from leaking from the liquid injection hole 11a.

[0097] Specifically in the embodiment, in combination with Figure 3 , Figure 10 and Figure 11 Understand that the liquid injection hole 11a includes an adjacent and communicating sink a1 and a through hole a2, the sealing nail 14 includes a connected boss portion 14g and a column portion 14k, the boss portion 14g is supported on the bottom wall of the sink a1 and is spaced from the side wall of the sink a1, and the column portion 14k is fitted into the through hole a2; the inner diameter D1 of the through hole a2, the inner diameter D2 of the sink a1, the outer diameter D3 of the boss portion 14g, and the outer diameter D4 of the column portion 14k satisfy: D4 < D1 < D3, 0.7D2 < D3 < D2.

[0098] D4 < D1 < D3. On the one hand, it will make it easier for the column portion 14k to be inserted into the through hole a2. On the other hand, during the process of inserting the sealing nail 14, when the boss portion 14g is limited by the bottom of the sink a1, it indicates that the sealing nail 14 is installed in place, and the installation of the sealing nail 14 is more reliable.

[0099] 0.7D2 < D3 < D2 indicates that there is a certain gap between the boss portion 14g and the side wall of the sink a1, which can be used for gap welding between the sealing nail 14 and the liquid injection hole 11a to improve the sealing effect.

[0100] In some embodiments, in combination with Figure 10 and Figure 12 Understand that the aperture D5 of the liquid injection flow channel 34r satisfies: D5 > D1. In this way, the electrolyte can flow smoothly from the liquid injection hole 11a into the liquid injection flow channel 34r without leakage.

[0101] In some embodiments, referring to Figure 3 and Figure 14 , the battery cell 100 further includes an insulating support member 50, the insulating support member 50 is arranged at the tab end J and is oppositely arranged with respect to the thermal conductive adhesive 40. The insulating support member 50 is provided with a hollow position 50u that penetrates along the thickness direction Z of the cover plate 11, and the hollow position 50u is sleeved around the tab 21.

[0102] Specifically, the hollow position 50u can be a hole structure or a groove structure, as long as it can be sleeved around the tab 21.

[0103] The insulating support 50 has an insulating effect and can strengthen the isolation between the isolation cover plate 11 and the electrode assembly 20. The insulating support 50 is supported at the tab end J. After the tab 21 on the tab end J sequentially passes through the hollow position 50u and the opening 30m, it extends into the glue filling space 30h. The tab 21 is usually in the shape of a thin sheet. The hollow position 50u is sleeved around the tab 21, which can support the tab 21 to a certain extent and strengthen the structural stability of the tab 21.

[0104] Specifically, in the embodiments of the present application, both the insulating glue filling member 30 and the insulating support 50 can be made of high molecular materials with good insulating properties, such as nylon (abbreviated as PA), polycarbonate (abbreviated as PC), polybutylene terephthalate (abbreviated as PBT), acrylonitrile-butadiene-styrene copolymer (abbreviated as ABS), etc. Fillers with enhanced thermal conductivity and insulation properties (such as Al2O3, AlN, BN, MgO, ZnO, NiO, Si3N4, etc.) can also be added to these high molecular materials.

[0105] Figure 13 Shows Figure 2 The enlarged schematic view at III in Figure 14 The structural schematic view of the insulating support 50 in some embodiments is shown. Figure 15 Shows Figure 14 Another perspective view of the insulating support 50 shown in

[0106] It is worth noting that, in one embodiment, as Figure 13 shown, the tab 21 includes a root segment 21a and a tail segment 21b that intersect, and a bending segment 21c that is tortuously connected between the root segment 21a and the tail segment 21b. The tail segment 21b is located in the glue filling space 30h and is welded to the pole column 12. The root segment 21a passes through the hollow position 50u; the thermal conductive glue 40 at least covers the tail segment 21b.

[0107] Specifically, the thermal conductive glue 40 can also cover the bending segment 21c. In actual application, before the tab 21 is bent, the electrode assembly 20 is in a horizontal state where its tab end J and the cover plate 11 are staggered in the horizontal plane. Since the tab 21 protrudes from the tab end J, the tab 21 is generally in a horizontal state, and it is easier to weld with the pole column 12 in the glue filling space 30h. After the tail segment 21b of the tab 21 is welded to the pole column 12, the tab 21 is bent until its tab end J is disposed opposite to the cover plate 11. Specifically, the root segment 21a of the tab 21 passes through the hollow position 50u.

[0108] Specifically in the embodiment, referring to Figure 14 andFigure 15 The hollow position 50u includes a support groove u1 arranged in a strip shape. One end of the support groove u1 in its longitudinal direction is closed, and the other end is configured as an opening u11. The insulating support 50 allows the tab 21 to be inserted into the support groove u1 through the opening u11.

[0109] When the cover plate 11 is a square plate, the longitudinal direction of the support groove u1 corresponds to the length direction X of the cover plate 11.

[0110] During actual operation, with the opening u11 of the support groove u1 facing the tab 21, move the insulating support 50 along the longitudinal direction of the support groove u1 at the tab end J. During this process, the tab 21 continuously inserts into the support groove u1 from the opening u11 of the support groove u1 until it is inserted in place (for example, when it abuts against the closed end, it is inserted in place). Generally, the groove width of the support groove u1 (the dimension of the support groove u1 in the direction perpendicular to its longitudinal direction) is slightly larger than or equal to the width of the tab 21. While facilitating the insertion of the tab 21, the support insulator can effectively support the tab 21.

[0111] In this way, the assembly process of the insulating support 50 and the tab 21 is simpler and easier to implement.

[0112] In some embodiments, referring to Figure 14 and Figure 15 the opening u11 of the support groove u1 is arranged in a flared shape, and its large-diameter end is arranged farther from the closed end of the support groove u1 than its small-diameter end.

[0113] The dimension of the opening u11 of the support groove u1 in the groove width direction decreases from its large-diameter end to its small-diameter end.

[0114] When inserting the tab 21, the tab 21 first passes through the large-diameter end of the opening u11 and then inserts into the interior of the support groove u1 through the small-diameter end of the opening u11. Designing the opening u11 in a flared shape makes it easier for the tab 21 to insert into the support groove u1.

[0115] Figure 16 Shows a partial structural schematic diagram of the battery cell 100 in some embodiments.

[0116] In some embodiments, in combination with Figure 2 , Figure 3 and Figure 16 it is understood that multiple tabs 21 are arranged side by side at intervals along the longitudinal direction of the support groove u1. Two insulating supports 50 are configured. The support grooves u1 of the adjacent partial tabs 21 penetrate through the same insulating support 50, and the support grooves u1 of the remaining adjacent tabs 21 penetrate through the support groove u1 of the other insulating support 50. The support grooves u1 of the two insulating supports 50 are arranged at intervals, and the openings u11 are arranged oppositely.

[0117] Obviously, the adjacent tabs 21 here refer to adjacent in the longitudinal direction of the support groove u1. In one embodiment, a plurality of tabs 21 are provided at the tab end J of each electrode assembly 20, and the plurality of tabs 21 are arranged side by side at intervals in the length direction X of the cover plate 11. Specifically, among the plurality of tabs 21, there may be included one or more positive tabs, and there may also be included one or more negative tabs. Along the length direction X of the cover plate 11 (corresponding to the longitudinal direction of the support groove u1), all the tabs 21 on each electrode assembly 20 are divided into two groups, one group of tabs 21 is inserted into the support groove u1 of one of the insulating supports 50, and the other group of tabs 21 is inserted into the support groove u1 of the other insulating support 50. The support grooves u1 of the two insulating supports 50 are configured with openings u11 facing each other. When the two insulating supports 50 can move relative to each other along the longitudinal direction of the support groove u1, each group of tabs 21 is inserted into the corresponding support groove u1.

[0118] At this time, at least one tab 21 is inserted into each support groove u1 of each insulating support 50. On the one hand, the number of configurations of the insulating support 50 can be reduced, and the cost can be lowered. On the other hand, the installation efficiency of the insulating support 50 can be improved, and thus the assembly efficiency of the battery cell 100 can be enhanced.

[0119] It should be noted that the same pole post 12 can be connected to the tab 21 on one electrode assembly 20, or can be simultaneously connected to the tabs 21 on different electrode assemblies 20.

[0120] In one embodiment, in combination with Figure 2 Understand that in order to improve the performance of the battery cell 100, at least two electrode assemblies 20 are configured inside the battery cell 100. There is a tab 21 on each of the at least two electrode assemblies 20 connected to the same pole post 12, and these tabs 21 are arranged at intervals in the direction of the groove width of the support groove u1. Optionally, the number of support grooves u1 on the insulating support 50 corresponds to a plurality. The plurality of support grooves u1 extend longitudinally in the same direction and are arranged side by side in the direction perpendicular to the longitudinal direction. Each support groove u1 correspondingly inserts one tab 21, so that the same insulating support 50 can support a plurality of tabs 21 connected to the same pole post 12, improving the assembly efficiency of the battery cell 100 and reducing the cost.

[0121] Of course, only one support groove u1 can also be configured on the insulating support 50, and each tab 21 is correspondingly inserted into the support groove u1 of the insulating support 50, or a plurality of tabs 21 connected to the same pole post 12 are correspondingly inserted into the support groove u1 of the insulating support 50 at the same time.

[0122] In a specific embodiment, two electrode assemblies 20 and two insulating supports 50 are configured, and a plurality of pole tabs 21 are configured on the pole tab end J of each electrode assembly 20 located at the same end, and all pole tabs 21 on each electrode assembly 20 are arranged at intervals along the length direction X of the cover plate 11, and all pole tabs 21 of the two electrode assemblies 20 are arranged one by one in the width direction Y of the cover plate 11. The two corresponding pole tabs 21 on the two electrode assemblies 20 are connected to the same pole column 12, and are respectively inserted into two different support grooves u1 on the same insulating support 50. The openings u11 of the support grooves u1 on the two insulating supports 50 are arranged oppositely, as recorded above, the support groove u1 of one of the insulating supports 50 is inserted into the adjacent part of the pole tabs 21 in the length direction X of the cover plate 11, and the support groove u1 of the other insulating support 50 is inserted into the adjacent part of the pole tabs 21.

[0123] In some embodiments, in combination Figure 3 It is understood that a liquid injection hole 11 a is provided on the cover plate 11 , and along the thickness direction Z of the cover plate 11 , the projection of the insulating support member 50 is staggered with the projection of the liquid injection hole 11 a .

[0124] Specifically, in one example (such as Figure 3 As shown in the figure, two insulating support members 50 are provided, and the two insulating support members 50 are arranged at intervals in the length direction X of the cover plate 11, and the interval space between the two corresponds to the injection hole 11a. In other examples, the insulating support member 50 may also be provided with a avoidance hole, and the avoidance hole is arranged opposite to the injection hole 11a.

[0125] When the above-mentioned convex column 34 is disposed on the insulating filler 30 , the projection of the convex column 34 includes the projection of the injection hole 11 a , and the projection of the convex column 34 is arranged to be staggered with the projection of the insulating support member 50 .

[0126] At this time, the insulating support 50 will not hinder the electrolyte from flowing toward the tab end J, which is conducive to the electrolyte to smoothly infiltrate the electrode assembly 20.

[0127] In some embodiments, reference Figure 14 , Figure 15 and Figure 16 The insulating support member 50 is provided with a liquid hole 50v, which connects the liquid injection hole 11a and the electrode assembly 20, and is staggered with the hollow position 50u.

[0128] Specifically, the liquid passing holes 50v are arranged through the insulating support 50 in the thickness direction Z of the cover plate 11, and are staggered from the hollow position 50u. The tab 21 in the hollow position 50u will not interfere with the liquid passing holes 50v and affect their liquid passing ability. Usually, a plurality of liquid passing holes 50v are arranged on the insulating support 50 to increase the liquid passing capacity. The plurality of liquid passing holes 50v are dispersedly arranged on the insulating support 50 to supply the electrolyte to flow to multiple positions of the electrode assembly 20.

[0129] Since the insulating support 50 is supported at the tab end J, to a certain extent, it will hinder the electrolyte from flowing to the electrode assembly 20. At this time, by arranging the liquid passing holes 50v on the insulating support 50, the path for the electrolyte to flow to the tab end J can be increased, so that the electrolyte can more evenly infiltrate into the electrode assembly 20, improving the cycling ability of the electrode assembly 20.

[0130] In some embodiments, in combination with Figure 14 and Figure 15 , the insulating support 50 includes a first end face d1 and a second end face d2 arranged opposite to each other in the thickness direction Z of the cover plate 11. The first end face d1 is configured as a planar structure that fits the electrode assembly 20. Reinforcing ribs 51 are arranged on the second end face d2, and the hollow position 50u penetrates through the reinforcing ribs 51.

[0131] The first end face d1 is flat, and its contact area with the tab end J is relatively large. The pressure exerted by the insulating support 50 on the electrode assembly 20 is more uniform, avoiding safety problems caused by local extrusion of the electrode assembly 20.

[0132] A plurality of reinforcing ribs 51 can be arranged on the second end face d2 of the insulating support 50. Each reinforcing rib 51 is arranged in a strip shape, and the plurality of reinforcing ribs 51 can intersect vertically and horizontally to form a mesh structure. The arrangement of the reinforcing ribs 51 can not only enhance the overall strength of the insulating support 50, but also the hollow position 50u penetrates through the reinforcing ribs 51, which can improve the supporting force of the insulating support 50 on the tab 21 passing through the hollow position 50u.

[0133] It is worth mentioning that by arranging the liquid passing holes 50v on the insulating support 50, since the liquid passing holes 50v penetrate the second end face d2, even if the reinforcing ribs 51 are arranged on the second end face d2, it can avoid the accumulation of the electrolyte on the second end face d2 and ensure the smooth outflow of the electrolyte.

[0134] Figure 17 and Figure 18 show exploded views of the battery cell 100 of some embodiments from different orientations.

[0135] In some embodiments, in combination with Figure 17 and Figure 18It is understood that the cover plate 11 has an outer end face W disposed away from the electrode assembly 20. One end surface of each pole column 12 protruding from the outer end face W is the first current-carrying surface GL1. The area S1 of the first current-carrying surfaces GL1 of all the pole columns 12 and the area S2 of the outer end face W satisfy: 0.45S2 ≤ S1 < S2.

[0136] Understandably, the pole column 12 protrudes from the outer end face W of the cover plate 11. One end surface of the pole column 12 in the thickness direction Z of the cover plate 11 is the first current-carrying surface GL1. The first current-carrying surface GL1 is located outside the battery cell 100, is disposed opposite to the electrode assembly 20, and is located at one end where the pole column 12 protrudes from the outer end face W. The first current-carrying surface GL1 of the pole column 12 and the outer end face W of the cover plate 11 can be but are not limited to being flat surfaces. The area S1 can be understood as the sum of the projected areas of the first current-carrying surfaces GL1 of all the pole columns 12 in the thickness direction Z of the cover plate 11. The area S2 can be understood as the sum of the projected areas of the outer end face W in the thickness direction Z of the cover plate 11.

[0137] Generally, the shapes and dimensions of each of the pole columns 12 are the same, and the areas of their first current-carrying surfaces GL1 are the same.

[0138] In practical applications, the pole column 12 is connected to a wire, a bus bar, etc. through the first current-carrying surface GL1 to connect to an external circuit. When the size of the outer end face W of the cover plate 11 is the same, the larger the value of S1 / S2, the larger the area S1 of the first current-carrying surfaces GL1 of all the pole columns 12, the larger the contact area between the pole column 12 and the wire, the bus bar, etc., the smaller the contact resistance, the stronger the current-carrying capacity of the pole column 12, and the higher the current transmission efficiency. At the same time, the large area of the first current-carrying surface GL1 can increase the heat dissipation between the pole column 12 and the outside, improving the heat dissipation capacity of the battery cell 100.

[0139] In this embodiment, the ratio of S1 / S2 takes values within the range of [0.45, 1), so that the area S1 of the first current-carrying surfaces GL1 of all the pole columns 12 is relatively large, which can effectively improve the current-carrying capacity and heat dissipation capacity of the pole column 12, and further improve the performance of the battery cell 100.

[0140] Specifically, S1 / S2 can be selected to take values of 0.45, 0.5, 0.6, 0.7, 0.8, 0.9, 0.95, and the values between any adjacent selected values. Further, to ensure the strength of the cover plate 11 and the electrical clearance between the pole columns 12, S1 / S2 ≤ 0.8.

[0141] In some embodiments, each pole column 12 has a second current-carrying surface GL2 disposed opposite to the first current-carrying surface GL1. The area S1' of the second current-carrying surfaces GL2 of all the pole columns 12 and the area S2 of the outer end face satisfy: 0.5S2 ≤ S1' < S2.

[0142] The other end surface of the terminal post 12 in the thickness direction Z of the cover plate 11 is the second current-carrying surface GL2, which faces the electrode assembly 20 and is connected to the tab 21. The second current-carrying surface GL2 can be, but is not limited to, a plane, and the area S1' can be understood as the sum of the projected areas of the second current-carrying surfaces GL2 of all the terminal posts 12 in the thickness direction Z of the cover plate 11.

[0143] The larger the value of S1’ / S2, the larger the area S1’ of the second current-carrying surfaces GL2 of all the terminal posts 12. Under the same current, it can not only reduce the internal resistance of the battery cell 100, but also disperse the current distribution, reduce the current density, reduce the polarization phenomenon caused by excessive local current density, and improve the charge and discharge efficiency. Moreover, it is also beneficial for the heat inside the battery cell 100 to be conducted to the external environment through the terminal posts 12, reduce the working temperature, and avoid performance degradation or safety hazards (such as thermal runaway) caused by overheating.

[0144] In this embodiment, the ratio of S1’ / S2 is in the range of [0.5, 1). The area S1’ of the second current-carrying surfaces GL2 of all the terminal posts 12 is relatively large, which can effectively reduce the current density, improve the charge and discharge efficiency, and enhance the heat dissipation and heat conduction capabilities inside the battery cell 100, thereby improving the performance of the battery cell 100.

[0145] Specifically, S1’ / S2 can be selected to take values of 0.5, 0.6, 0.7, 0.8, 0.9, 0.95, and the values between any adjacent selected values. Further, to ensure the strength of the cover plate 11 and the electrical clearance between the terminal posts 12, S1’ / S2 ≤ 0.8.

[0146] In some embodiments, the thermal conductive adhesive 40 can insulatively coat the side of the terminal post 12 facing the tab 21, thereby ensuring the electrical clearance between the terminal posts 12 inside adjacent battery cells 100, and thus maximizing the projected area of the second current-carrying surface GL2. The thermal conductive adhesive 40 has insulation properties and can coat the entire side of the terminal post 12 facing the tab 21 (including the welding area between the terminal post 12 and the tab 21), that is, coat the second current-carrying surface GL2 of the terminal post 12, so as to achieve electrical isolation between adjacent terminal posts 12.

[0147] Based on this, the projected area of the second current-carrying surface GL2 of the terminal post 12 can be larger than the projected area of the first current-carrying surface GL1 of the terminal post 12. That is, S1’ is greater than S1. When the second current-carrying surface GL2 of the terminal post 12 is designed to have a larger area, the heat generation inside the battery cell can be reduced. At the same time, the larger contact area can provide more current flow paths, enabling the current to be evenly distributed in the connection area between the terminal post 12 and the tab 21, avoiding local overheating caused by excessive local current density. Additionally, the connection strength between the tab 21 and the terminal post 12 can be increased, enabling it to withstand greater mechanical stress and avoiding problems such as connection loosening and breakage caused by vibration and impact. Moreover, the projected area of the first current-carrying surface GL1 of the terminal post 12 is designed to be smaller than the projected area of the second current-carrying surface GL2, leaving more space on the side of the terminal post 12 away from the electrode assembly 20 of the cover plate 11. This can facilitate the spatial layout between the terminal post 12 and the external busbar, improve the reliability of the connection between the terminal post 12 and the busbar, and ensure the electrical clearance between adjacent terminal posts 12.

[0148] In some embodiments, referring to Figure 2 , the end cap 10 includes N terminal posts 12, and the N terminal posts 12 are arranged side by side and spaced apart along the length direction X of the cover plate 11, where N≥4 and N is an even number.

[0149] In conventional designs, the number of terminal posts 12 provided on the same end cap 10 is 1 or 2. In this embodiment, when 4 or more even-numbered terminal posts 12 are configured on the end cap 10, on the one hand, the current-carrying area between the terminal posts 12 and the tabs 21, as well as between the terminal posts 12 and the external circuit, can be increased. This can not only reduce the current-carrying resistance of the battery cell 100 but also reduce the current-carrying density of the battery cell 100, reduce local temperature rise, and improve the charge and discharge efficiency and heat dissipation capacity of the battery cell 100.

[0150] On the other hand, the terminal posts 12 are dispersedly distributed relative to the cover plate 11. Multiple tabs 21 can be correspondingly configured on the electrode assembly 20 inside the battery cell 100 and are connected to the terminal posts 12 one by one. At this time, the current transmission of the electrode assembly 20 can be carried out at multiple positions, which helps to improve the temperature rise uniformity of the electrode assembly 20 and the temperature uniformity of the battery cell 100.

[0151] Specifically in the embodiment, the N terminal posts 12 form multiple terminal post groups, and each terminal post group includes two terminal posts 12 with opposite polarities. All the terminal posts 12 are arranged at intervals along the length direction X of the cover plate 11.

[0152] That is to say, among the multiple terminal posts 12, some of the terminal posts 12 are positive terminal posts, and some of the terminal posts 12 are negative terminal posts, and the number of positive terminal posts and negative terminal posts is the same. Preferably, the positive terminal posts and the negative terminal posts are arranged alternately.

[0153] At this time, multiple positive electrode posts and multiple negative electrode posts are arranged on the same end cover 10, which not only enables the battery cell 100 to have high charge and discharge efficiency and good heat dissipation ability, but also has high space utilization rate of the battery cell 100 in the thickness direction Z of the cover plate 11. At the same time, the same liquid cooling plate can be used to cool the battery cell 100, reducing the liquid cooling cost of the battery.

[0154] In a specific embodiment, as Figure 2 shown, the number of the electrode posts 12 is configured to be 4, including two positive electrode posts and two negative electrode posts, and the positive electrode posts and the negative electrode posts are arranged alternately. In this way, in the case of the same S1 and S1', compared with setting a larger number of electrode posts 12, the assembly efficiency of the battery cell 100 is higher.

[0155] Figure 19 The structural schematic diagram of the end cover 10 of some embodiments is shown. Figure 20 The cross-sectional schematic diagram of the end cover 10 of some embodiments is shown.

[0156] Specifically in the embodiment, referring to Figure 19 , the dimension of the first current-carrying surface GL1 of each electrode post 12 in the length direction X of the cover plate 11 is b, and the dimension of the first current-carrying surface GL1 of each electrode post 12 in the width direction Y of the cover plate 11 is a. In the plane of the outer end face W, the interval between the first current-carrying surfaces GL1 of adjacent electrode posts 12 is m, the distance between the first current-carrying surfaces GL1 of the head and tail two electrode posts 12 and the edge of the outer end face W in the length direction X is p, and the distance between the first current-carrying surfaces GL1 of all the electrode posts 12 and the edge of the outer end face W in the width direction Y is n, satisfying: S2=(a + 2n)*[N*b + 2p + (N - 1)*m], where m≥2mm, n≥4mm, p≥4mm.

[0157] Each electrode post 12 is arranged at equal intervals along the length direction X of the cover plate 11. m, n and p determine the arrangement position of the electrode posts 12 on the cover plate 11. When the three are smaller, with the size of the cover plate 11 unchanged, the area occupied by the first current-carrying surface GL1 of the electrode posts 12 on the outer end face W of the cover plate 11 is larger. As described above, the larger the area of the first current-carrying surface GL1, the larger the contact area between the electrode post 12 and the wire, the conductive bar, etc., the smaller the contact resistance, the stronger the current-carrying capacity of the electrode post 12, and the higher the current transmission efficiency. At the same time, the large area of the first current-carrying surface GL1 can increase the heat dissipation between the electrode post 12 and the outside, improving the heat dissipation ability of the battery cell 100. Of course, the sizes of m, n and p cannot be infinitely small, and the smaller they are, the lower the strength of the cover plate 11.

[0158] When m, n, and p each need to satisfy the above relationships, the strength of the cover plate 11 and the performance of the battery cell 100 can be taken into account. Further, m ≤ 5 mm, n ≤ 10 mm, and p ≤ 10 mm. In this case, the strength of the cover plate 11 and the performance of the battery cell 100 can be taken into account.

[0159] In practical applications, the cover plate 11 with a square shape can be designed according to the above dimensions. Specifically, (a + 2n) can be regarded as the width dimension of the cover plate 11, and [N * b + 2p + (N - 1) * m] can be regarded as the length dimension of the cover plate 11. Thus, the area S2 of the outer end face W of the cover plate 11 is determined. At this time, after determining the dimensions of the pole column 12 and the spacing distances n, p, and m, the dimensions of the cover plate 11 can be determined based on these data without considering the occupation of other structures on the cover plate 11, which can simplify the design of the cover plate 11.

[0160] Specifically in the embodiment, refer to Figure 19 , the projection of the pole column 12 in the thickness direction Z of the cover plate 11 is rectangular. Generally, the shape of the cover plate 11 is square. In this case, the pole column 12 is designed as a square structure, and the end cover 10 is not only more beautiful but also the structure of the end cover 10 can be simplified. Under the same m, n, and p, the configuration area of the pole column 12 is larger, and the effect on improving the performance of the battery cell 100 is more obvious.

[0161] Of course, in other embodiments, the pole column 12 can also be in a cylindrical or other prismatic structure.

[0162] In some embodiments, the total length G1 of the first current-carrying surface GL1 of all the pole columns 12 in the length direction X of the cover plate 11, the total length G0 of the cover plate 11, and the total length G2 of the second current-carrying surface GL2 of all the pole columns 12 in the length direction X satisfy: 0.5G0 < G1 < G2 < G0.

[0163] Specifically, for the sake of simplifying the design, the dimensions of the first current-carrying surface GL1 and the second current-carrying surface GL2 in the width direction Y of the cover plate 11 are the same, and the dimensions of the first current-carrying surface GL1 and the second current-carrying surface GL2 in the length direction X of the cover plate 11 are designed to be different, so that their areas are not equal. Further, for the sake of simplifying the design, the dimensions of the first current-carrying surface GL1 of each pole column 12 in each direction are the same, and the dimensions of the second current-carrying surface GL2 of each pole column 12 in each direction are the same.

[0164] When 0.5G0 < G1 < G2 < G0, and the width dimensions of the first current-carrying surface GL1 and the second current-carrying surface GL2 are the same, the area of the first current-carrying surface GL1 can be made smaller than the area of the second current-carrying surface GL2, reducing the over-current density of the battery cell 100, improving its charge and discharge efficiency, and at the same time being able to take into account the strength of the cover plate 11 and the structural compactness of the battery cell 100.

[0165] In some embodiments, referring to Figure 20 , a liquid injection hole 11a penetrating through its outer end face W is provided on the cover plate 11, and each pole column 12 protrudes from the outer end face W. Along the length direction X of the cover plate 11, an interval area T is formed between every two adjacent pole columns 12, and the liquid injection hole 11a is arranged in a part of the interval area T. The size of the interval area T where the liquid injection hole 11a is arranged in the length direction X is m1, the aperture of the liquid injection hole 11a is D2, and the size of the interval area T where the liquid injection hole 11a is not arranged in the length direction X is m2, satisfying: 0.4m1 ≤ D2 < m1; m2 ≤ m1.

[0166] The interval area T refers to the area on the cover plate 11 between two adjacent pole columns 12 in its length direction X. The liquid injection hole 11a is used for injecting electrolyte. The liquid injection hole 11a is arranged in a part of the interval area T and penetrates through this interval area T. The number of the liquid injection holes 11a is usually one and is arranged in one interval area T. The aperture D2 of the liquid injection hole 11a refers to the maximum dimension of the projection of the liquid injection hole 11a along the thickness direction Z of the cover plate 11. When the liquid injection hole 11a includes the above-mentioned sink a1 and the above-mentioned through hole a2, its maximum projection dimension is the inner diameter dimension of the sink a1.

[0167] In this embodiment, m2 ≤ m1, that is, the length of the interval area T where the liquid injection hole 11a is not arranged is less than the length of the interval area T where the liquid injection hole 11a is arranged, so that it is convenient to layout the liquid injection hole 11a. At the same time, 0.4m1 ≤ D2 < m1, and the area occupied by the liquid injection hole 11a in the interval area T where it is located is appropriate, and the influence on the strength of the interval area T is small.

[0168] In some embodiments, referring to Figure 16 it is understood that a plurality of pole tabs 21 are configured, and the plurality of pole tabs 21 are arranged at intervals along the length direction X of the cover plate 11. Each pole column 12 is correspondingly welded to a pole tab 21, and the polarities of adjacent pole tabs 21 are opposite. In the length direction X of the cover plate 11, the length L1 of the pole tab 21 with negative polarity and the length L2 of the pole tab 21 with positive polarity satisfy: L1 ≤ L2.

[0169] The pole tab 21 with negative polarity is called the negative pole tab, and the pole tab 21 with positive polarity is called the positive pole tab. The negative pole tab is usually made of copper, and the positive pole tab is usually made of aluminum. When L1 = L2, it indicates that the length L2 of the positive pole tab and the length L1 of the negative pole tab are the same. In the case where the width dimensions of the positive pole tab and the negative pole tab are the same, the size structures of each pole tab 21 are the same, and thus the preparation of the electrode assembly 20 can be simplified. Since the conductivity of aluminum is weaker than that of copper, when L1 < L2, in the case where the width dimensions of the positive pole tab and the negative pole tab are the same, the overcurrent capabilities of the positive pole tab and the negative pole tab can be balanced, and excessive heat generation of the positive pole tab can be avoided.

[0170] In some other embodiments, the length L1 of the tab 21 with a negative electrode polarity and the length L2 of the tab 21 with a positive electrode polarity satisfy: 0.25L2 ≤ L1 ≤ 0.9L2. At this time, L1 / L2 takes values in the range of 0.25 to 0.9. When the width dimensions of the positive tab and the negative tab are the same, the current-carrying capacities and heat generation conditions of the positive tab and the negative tab can be made to match as much as possible. Specifically, L1 / L2 can be selected to take values of 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.85, 0.9, and the values between any two adjacent selected values.

[0171] Generally, the dimensions of each tab 21 in the width direction Y of the cover plate 11 (i.e., the width of the tab 21) are equal to each other, which simplifies the preparation of the battery cell 100.

[0172] In some embodiments, referring to Figure 2 , the battery cell 100 further includes a housing 60. The housing 60 includes a receiving cavity with an open end u11. The cover plate 11 is covered on the open end u11 of the receiving cavity, and the outer end face W of the cover plate 11 faces away from the receiving cavity. The electrode assembly 20 is received in the receiving cavity. The housing 60 can be a steel shell, an aluminum shell, etc., which cooperate with the cover plate 11 to form a receiving cavity for receiving the electrode assembly 20. The housing 60 and the cover plate 11 can be hermetically connected by welding, snap connection, etc.

[0173] In a further embodiment, referring to Figure 2 , the battery cell 100 further includes a heat-conducting coating member 70. The heat-conducting coating member 70 is located in the receiving cavity and covers the outside of the electrode assembly 20. The heat-conducting coating member 70 has heat-conducting properties, and it can be graphene, a heat-conducting plastic film (such as PP, PC, etc.).

[0174] At this time, the heat generated by the electrode assembly 20 is transferred to the housing 60 through the heat-conducting coating member 70. The housing 60 can exchange heat with an external liquid cooling structure, thereby improving the heat exchange efficiency between the battery cell 100 and the liquid cooling structure, greatly reducing the working heat of the battery cell 100, and improving the reliability of the battery cell 100.

[0175] In a further embodiment, the battery cell 100 further includes an explosion-proof valve (not shown), and the explosion-proof valve is provided on the side of the housing 60 away from the end cover 10.

[0176] In a specific embodiment of the present application, the battery cell 100 includes the above-mentioned end cap 10, outer shell 60, insulating caulking member 30, insulating support member 50, and electrode assembly 20. The insulating caulking member 30 is thermally connected to the cover plate 11 and forms a caulking space 30h. One end of the insulating caulking member 30 facing the tab end J forms an opening 30m. After the tab 21 on the tab end J passes through the support groove u1 of the insulating support member 50, it extends into the caulking space 30h through the opening 30m and is welded to the pole column 12 extending into the caulking space 30h through the avoidance hole 30i on the insulating caulking member 30. A thermally conductive adhesive 40 is filled in the caulking space 30h, and the thermally conductive adhesive 40 covers the tab 21 and the pole column 12. The insulating caulking member 30 is provided with a convex column 34, and the convex column 34 is arranged corresponding to the liquid injection hole 11a on the cover plate 11 and has a liquid injection flow channel 34r communicating with the liquid injection hole 11a. The convex column 34 extends beyond the range of the insulating caulking member 30 and extends toward the tab end J. The insulating support member 50 avoids the convex column 34 to facilitate the uniform infiltration of the electrolyte into the electrode assembly 20.

[0177] Figure 21 FIG. shows a schematic flow chart of a method for manufacturing the battery cell 100 according to some embodiments. Figure 22 FIG. shows the state change of the electrode assembly 20 during the manufacturing process of the battery cell 100.

[0178] In addition, please refer to Figure 21 , the embodiment of the present application further provides a method for manufacturing a battery cell 100, which is applied to the battery cell 100 in any of the above embodiments. The manufacturing method includes: S1. Pass the pole column 12 on the end cap 10 through the avoidance hole 30i of the insulating caulking member 30 so that the pole column 12 extends into the caulking space 30h of the insulating caulking member 30.

[0179] Specifically, the inner side of the cover plate 11 of the end cap 10 can be turned upward, the opening 30m of the insulating caulking member 30 can be turned upward, and the insulating caulking member 30 is pressed downward from top to bottom so that the welding section 12c of the pole column 12 passes through the avoidance hole 30i of the insulating caulking member 30 until the insulating caulking member 30 abuts against the cover plate 11. At this time, the welding section 12c is located in the caulking space 30h.

[0180] S2. Turn the opening 30m of the insulating caulking member 30 upward, and weld the tab 21 of the electrode assembly 20 in the lying state to the pole column 12 located in the caulking space 30h. When in the lying state, the tab end J of the electrode assembly 20 is located on one side of the electrode assembly 20 in the horizontal direction.

[0181] As Figure 22In the state shown by the dashed line in [Figure], when the electrode assembly 20 is in a lying state, the tab end J of the electrode assembly 20 is arranged substantially vertically, and its tab 21 extends substantially horizontally. After passing through the opening 30m, the tab 21 is welded to the welding section 12c located in the insulating encapsulant 30.

[0182] S3. Pour the thermal conductive adhesive 40 into the encapsulant space 30h through the opening 30m. Insert the glue supply pipeline of the glue filling device into the encapsulant space 30h through the opening 30m, so that the encapsulant space 30h is filled with the thermal conductive adhesive 40. Specifically, the filling thickness of the thermal conductive adhesive 40 does not exceed the glue overflow channel 33q formed by the partition strip 33, so as to reduce the consumption of the thermal conductive adhesive 40.

[0183] S4. Bend the tab 21 until the tab end J of the electrode assembly 20 is oppositely arranged with the opening 30m of the insulating encapsulant 30.

[0184] Specifically, after the thermal conductive adhesive 40 is cured, the tab 21 can be bent, and the electrode assembly 20 is folded in the direction shown by the arrow in [Figure], until the tab end J of the electrode assembly 20 is opposite to the opening 30m of the insulating encapsulant 30. At this time, the tab end J is arranged substantially horizontally (as shown by the solid line in [Figure]). Figure 22 Figure 21 Figure 21

[0185] In the above method for preparing the battery cell 100, the insulating encapsulant 30 is inverted so that its opening 30m faces upward. When the electrode assembly 20 is in a lying state, the tab 21 is inserted into the encapsulant space 30h through the opening 30m and welded to the pole column 12 in the encapsulant space 30h, making the welding operation of the tab 21 and the pole column 12 simpler and more convenient. In addition, after the tab 21 and the pole column 12 are welded, the thermal conductive adhesive 40 can be poured through the opening 30m, which can ensure that the thermal conductive adhesive 40 effectively coats the tab 21 and the pole column 12, and the pouring process of the thermal conductive adhesive 40 is easier to control.

[0186] In other embodiments, when the battery cell 100 includes a thermal conductive coating member 70, before step S4, it includes: S31. Coat the outer periphery of the electrode assembly 20 with the thermal conductive coating member 70. Specifically, before folding the electrode assembly 20, coating the outer periphery of each electrode assembly 20 with the thermal conductive coating member 70 is more conducive to installing the thermal conductive coating member 70.

[0187] In other embodiments, when the battery cell 100 includes an insulating support member 50 and a housing 60, and the insulating support member 50 includes the above support groove u1 and opening u11, after step S4, it further includes: S5. Orient the first end face d1 of the insulating support member 50 towards the tab end J of the electrode assembly 20; through the opening u11 of the support groove u1 of the insulating support member 50, insert the insulating support member 50 along the extending direction of the support groove u1 onto the outer periphery of the tab 21. Specifically, the intermediate member obtained in step S4 can be turned over as a whole up and down. After obtaining the end cap 10 facing upwards and the electrode assembly 20 facing downwards, push the insulating support member 50 along the tab end J so that the tab 21 is inserted into the support groove u1 from the opening u11 of the support groove u1 of the insulating support member 50.

[0188] S6. Weld the outer shell 60 to the cover plate 11 of the end cap 10, and ensure that the heat-conducting coating member 70, the electrode assembly 20, the insulating filling member 30, and the insulating support member 50 are all located in the accommodation cavity formed by the outer shell 60 and the cover plate 11.

[0189] Specifically, after the intermediate member obtained in step S5 is placed as a whole in the accommodation cavity of the outer shell 60, the cover plate 11 covers the opening u11 end of the outer shell 60, and the cover plate 11 is welded to the opening u11 end of the outer shell 60.

[0190] In addition, after step S6, there are usually also conventional processes such as liquid injection and formation. The specific operations of each process are not elaborated here and can be referred to common general knowledge.

[0191] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combinations of these technical features do not conflict, they should be considered as falling within the scope described in this specification.

[0192] The above embodiments only represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A battery cell (100), characterized in that, Comprising: An end cap (10), including a cover plate (11) and a pole column (12) provided on the cover plate (11); An electrode assembly (20), having an ear end (J) arranged facing the cover plate (11), and an ear (21) protruding from the ear end (J); An insulating glue filling member (30), provided between the electrode assembly (20) and the cover plate (11), having a glue filling space (30h) and an avoidance hole (30i) communicating with the glue filling space (30h). One end of the insulating glue filling member (30) facing the ear end (J) is provided with an opening (30m). The ear (21) extends into the glue filling space (30h) through the opening (30m). The pole column (12) passes through the avoidance hole (30i) and is connected to the ear (21) within the glue filling space (30h); and A thermal conductive glue (40), filled into the glue filling space (30h) through the opening (30m) and covering the ear (21) and the pole column (12).

2. The battery cell (100) according to claim 1, characterized in that, The projection of the opening (30m) along the thickness direction (Z) of the cover plate (11) includes the projection of the ear end (J) along the thickness direction (Z); and / or, The pole column (12) includes a mating section (12b), and the mating section (12b) mates with the avoidance hole (30i) by itself or through a seal (13).

3. The battery cell (100) according to claim 2, characterized in that, The pole column (12) includes the mating section (12b) and a welding section (12c) adjacently connected to the mating section (12b). The welding section (12c) is located in the glue filling space (30h) and is welded to the ear (21); along the thickness direction (Z) of the cover plate (11), the projection of the welding section (12c) exceeds the projections of the mating section (12b) and the avoidance hole (30i); The inner wall of the avoidance hole (30i) is configured to be deformable.

4. The battery cell (100) according to claim 3, characterized in that, A plurality of notches (30n) are recessed on the inner wall of the avoidance hole (30i), and the plurality of notches (30n) are arranged at intervals along the circumferential direction of the avoidance hole (30i); Each of the notches (30n) penetrates the wall of the insulating glue filling member (30) along the thickness direction (Z), so that the inner wall of the avoidance hole (30i) can be bent and deformed.

5. The battery cell (100) according to any one of claims 1 to 4, characterized in that, The insulating glue filling member (30) includes a partition strip (33) and / or a convex column (34); The partition strip (33) is located in the glue filling space (30h) and divides the glue filling space (30h) into a main space (h1) and an overflow glue space (h2). The avoidance hole (30i) communicates with the main space (h1), and the ear (21) extends into the main space (h1); the partition strip (33) is formed with an overflow glue channel (33q) that communicates the overflow glue space (h2) with the main space (h1); at least the main space (h1) is filled with the thermal conductive glue (40); The cover plate (11) is provided with a liquid injection hole (11a). The convex post (34) is located in the glue filling space (30h), extends toward the tab end (J) to pass through the opening (30m), and is spaced apart from the tab end (J). A liquid injection flow channel (34r) communicating with the liquid injection hole (11a) is formed in the convex post (34). Along the thickness direction (Z) of the cover plate (11), the projection of the outlet end of the liquid injection hole (11a) is within the projection range of the inlet end of the liquid injection flow channel (34r).

6. The battery cell (100) according to any one of claims 1 to 4, characterized in that, The battery cell (100) further includes an insulating support member (50). The insulating support member (50) is disposed at the tab end (J) and is disposed opposite to the thermal conductive adhesive (40). The insulating support member (50) is provided with a hollow position (50u) penetrating along the thickness direction (Z) of the cover plate (11). The hollow position (50u) is sleeved around the tab (21).

7. The battery cell (100) according to any one of claims 1 to 4, characterized in that, The cover plate (11) has an outer end face (W) disposed away from the electrode assembly (20). Each pole column (12) has a first current-carrying surface (GL1) disposed away from the electrode assembly (20). The area S1 of the first current-carrying surfaces (GL1) of all the pole columns (12) and the area S2 of the outer end face (W) satisfy: 0.45S2 ≤ S1 < S2; Each pole column (12) has a second current-carrying surface (GL2) disposed opposite to the first current-carrying surface (GL1). The area S1' of the second current-carrying surfaces (GL2) of all the pole columns (12) and the area S2 of the outer end face (W) satisfy: 0.5S2 ≤ S1' < S2.

8. The battery cell (100) according to claim 7, characterized in that, The end cover (10) includes N pole columns (12). The N pole columns (12) are arranged side by side and spaced apart along the length direction (X) of the cover plate (11). N ≥ 4 and is an even number; The dimension of the first current-carrying surface (GL1) of each pole column (12) in the length direction (X) of the cover plate (11) is b, and the dimension of the first current-carrying surface (GL1) of each pole column (12) in the width direction (Y) of the cover plate (11) is a; In the plane where the outer end face (W) is located, the interval between the first current-carrying surfaces (GL1) of adjacent pole columns (12) is m. The distance between the first current-carrying surface (GL1) of the head and tail two pole columns (12) and the edge of the outer end face (W) in the length direction (X) is p, and the distance between the first current-carrying surfaces (GL1) of all the pole columns (12) and the edge of the outer end face (W) in the width direction (Y) is n; Satisfy: S2 = (a + 2n) * [N * b + 2p + (N - 1) * m], where m ≥ 2mm, n ≥ 4mm, p ≥ 4mm.

9. The battery cell (100) according to any one of claims 1 to 4, characterized in that, A plurality of tabs (21) are configured. The plurality of tabs (21) are spaced apart along the length direction (X) of the cover plate (11). Each pole column (12) is correspondingly welded to one tab (21). The polarities of adjacent tabs (21) are opposite; In the length direction (X) of the cover plate (11), the length L1 of the tab (21) with negative polarity and the length L2 of the tab (21) with positive polarity satisfy: L1 ≤ L2, or, 0.25L2 ≤ L1 ≤ 0.9L2.

10. A method for preparing a battery cell (100), applied to the battery cell (100) according to any one of claims 1 to 9, characterized in that, The preparation method includes: Pass the terminal post (12) on the end cap (10) through the avoidance hole (30i) of the insulating potting member (30) so that the terminal post (12) extends into the potting space (30h) of the insulating potting member (30); Turn the opening (30m) of the insulating potting member (30) upward, and weld the tab (21) of the electrode assembly (20) in a lying state to the terminal post (12) located in the potting space (30h); when in the lying state, the tab end (J) of the electrode assembly (20) is located on one side of the electrode assembly (20) in the horizontal direction; Pour the thermal conductive adhesive (40) into the potting space (30h) through the opening (30m); Bend the tab (21) and turn over the electrode assembly (20) until the tab end (J) of the electrode assembly (20) is arranged opposite to the opening (30m) of the insulating potting member (30).

Images