Battery

Abstract

The present application provides a battery, comprising a cell pack and a top cover assembly. A top wall and a side wall of a pole in the top cover assembly enclose to form an accommodating cavity for accommodating at least a portion of a tab extending from a cell pack body, thereby preventing the tab from connecting to an outer surface of the pole and thus occupying excessive space. Given a certain volume and weight of the battery, by means of providing the accommodating cavity within the pole to accommodate at least a portion of the tab, the spatial and weight proportions of the tab and the pole in the battery are greatly reduced, thereby increasing the volume and weight proportions of the cell pack body in the battery and increasing battery capacity and energy density. On the basis of providing the accommodating cavity within the pole to accommodate the tab, the distance between the top wall of the pole and a top surface of the cell pack body is designed to be less than or equal to 30 mm, thereby reducing the space occupied between the pole and the cell pack body, reducing the spatial proportion of the tab, and increasing the energy density of the battery.

Description

Battery

[0001] This application claims priority to the Chinese patent application No. 2024223905407, filed on September 29, 2024, with the Chinese Patent Office, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of batteries, in particular to a battery. BACKGROUND

[0003] In the related art, the core package of the battery is welded to the pole by a metal connecting piece, and the tab of the core package extends and is welded to the outer surface of the pole by the metal connecting piece. TECHNICAL PROBLEM

[0004] The arrangement of the tab of the core package, the metal connecting piece and the pole occupies a large space of the battery, and reduces the energy density of the battery. In addition, the arrangement of the top cover assembly and the core package of the battery also occupies a space of the battery, and reduces the energy density of the battery. TECHNICAL SOLUTION

[0005] The present application provides a battery, comprising: a core package, the core package comprising a core package body and a tab connected to the core package body; a top cover assembly, the top cover assembly comprising a shell and a pole, the shell being arranged on the core package body, the pole being mounted on the shell, a top wall and a side wall of the pole surrounding to form a receiving cavity, at least part of the tab being received in the receiving cavity; wherein the distance between the top wall of the pole and the top surface of the core package body is d, and d≤30mm. ADVANTAGEOUS EFFECT

[0006] The present application has the advantage that, compared with the related art, the top wall and the side wall of the pole in the top cover assembly of the present application surround to form a receiving cavity to receive at least part of the tab extending from the core package body, thereby avoiding the situation that the tab is connected to the outer surface of the pole and occupies too much space; under the condition that the volume and weight of the battery are constant, by arranging the receiving cavity in the pole to receive at least part of the tab, the space and weight proportion of the tab and the pole in the battery are greatly reduced, thereby increasing the volume and weight proportion of the core package body in the battery, and further increasing the battery capacity and energy density; on the basis of arranging the receiving cavity in the pole to receive the tab, the distance between the top wall of the pole and the top surface of the core package body is designed to be less than or equal to 30mm, which can reduce the space occupied between the pole and the core package body, and compress the space proportion of the tab, thereby improving the energy density of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0007] Fig. 1 is a schematic view of the cross-sectional structure of the battery according to an embodiment of the present application;

[0008] Fig. 2 is an enlarged schematic view of the area A in Fig. 1;

[0009] Fig. 3 is a size diagram of the area A in Fig. 1;

[0010] Fig. 4 is a sectional structure diagram of a battery according to another embodiment of the present application;

[0011] Fig. 5 is an enlarged diagram of the area A in Fig. 4;

[0012] Fig. 6 is a size diagram of the area A in Fig. 4;

[0013] Fig. 7 is a sectional structure diagram of a battery according to still another embodiment of the present application;

[0014] Fig. 8 is an enlarged diagram of the area A in Fig. 7;

[0015] In the drawings, reference numerals:

[0016] Battery 100; core pack 110; core pack body 111; tab 112; connecting section 1121; bending section 1122; extending section 1123; top cover assembly 120; shell 121; pole 122; upper shell 1211; lower shell 1212; accommodating cavity M; first welding part W1; second welding part W2. Embodiments of the present application

[0017] An embodiment of the present application provides a battery 100, please refer to Figs. 1-3. In this embodiment, the battery 100 includes a core pack 110, a top cover assembly 120 and a shell, as shown in Fig. 1.

[0018] Specifically, the core pack 110 includes a core pack body 111 and a tab 112 connected to the core pack body 111. Optionally, the core pack body 111 includes a protective film and a plurality of positive plates, a plurality of separators and a plurality of negative plates arranged in the protective film. The core pack body 111 and the protective film are arranged in the shell (not shown). In the protective film, the plurality of positive plates and the plurality of negative plates are arranged in sequence, and a separator is arranged between every two adjacent positive plates and negative plates. The tab 112 includes at least one positive tab 112 and at least one negative tab 112. Specifically, each positive plate is connected to a positive tab 112 cluster, and a plurality of positive tab 112 clusters are gathered to form a positive tab 112. Similarly, each negative plate is connected to a negative tab 112 cluster, and a plurality of negative tab 112 clusters are gathered to form a negative tab 112.

[0019] Optionally, the battery 100 includes two core packs 110, and a top cover assembly 120 is arranged above the two core packs 110, and one core pack 110 is arranged with one tab 112, thereby being arranged in the accommodating cavity M of one pole 122 of the top cover assembly 120, and two tabs 112 connected to the two core packs 110, respectively, are arranged, as shown in Fig. 2.

[0020] In the embodiment, the top cover assembly 120 comprises a shell 121 and a pole 122. The shell 121 is arranged on the core package body 111, and a cover is arranged on the opening of the shell to encapsulate the core package 110. The pole 122 is mounted on the shell 121. The top wall and the side wall of the pole 122 surround a receiving cavity M, and at least part of the tab 112 is received in the receiving cavity M, as shown in FIG. 2.

[0021] In the embodiment, the distance between the top wall of the pole 122 and the top surface of the core package body 111 is d, and d≤30mm, as shown in FIG. 3. Optionally, d is 30mm, 29mm, 28mm, 27mm, 25mm, 24mm, 23mm, 22mm, 20mm, 18mm, 16mm, 15mm or 13mm, etc.

[0022] In the top cover assembly 120 of the application, the top wall and the side wall of the pole 122 surround the receiving cavity M to receive at least part of the tab 112 extending from the core package body 111, so as to avoid the situation that the tab 112 is connected to the outer surface of the pole 122 and occupies too much space. In the case that the volume and the weight of the battery 100 are constant, by arranging the receiving cavity M in the pole 122 to receive at least part of the tab 112, the space and the weight proportion of the tab 112 and the pole 122 in the battery 100 are greatly reduced, so as to increase the volume and the weight proportion of the core package body 111 in the battery 100, and further increase the capacity and the energy density of the battery 100. On the basis of arranging the receiving cavity M in the pole 122 to receive the tab 112, the distance between the top wall of the pole 122 and the top surface of the core package body 111 is less than or equal to 30mm, which can reduce the space occupied between the pole 122 and the core package body 111, and compress the space proportion of the tab 112, so as to improve the energy density of the battery 100.

[0023] Optionally, an explosion-proof valve (not shown) is further arranged in the top cover assembly 120 to perform pressure relief and explosion prevention when the battery 100 is in thermal runaway. Specifically, the positive pole 122 and the negative pole 122 are symmetrically arranged on the two sides of the explosion-proof valve.

[0024] In the embodiment, the shell 121 includes an upper shell 1211 and an upper shell 1212. The upper shell 1212 is arranged above the core pack body 111, and the upper shell 1211 is arranged above the upper shell 1212, so that a containing space is formed between the upper shell 1211 and the upper shell 1212. The pole column 122 is installed in the containing space between the upper shell 1211 and the upper shell 1212. The upper shell 1211 is provided with a through hole to allow the pole column 122 to extend outwards and be connected to an external electrical equipment. The upper shell 1212 is provided with a avoiding hole to avoid the tab 112, so that the tab 112 can extend from the avoiding hole and be accommodated in the containing cavity M in the pole column 122. Specifically, the pole column 122 includes a positive pole column 122 and a negative pole column 122, and the positive tab 112 and the positive pole column 122 are correspondingly arranged, and the negative tab 112 and the negative pole column 122 are correspondingly arranged.

[0025] As shown in FIG. 3, the distance between the top wall of the pole column 122 and the top surface of the upper shell 1212 is d1, and d1≤15 mm. Optionally, d1 is 15 mm, 14 mm, 13 mm, 12 mm, 11 mm, 10 mm, 9 mm, 8 mm, or 7 mm, etc. The space between the top wall of the pole column 122 and the top surface of the upper shell 1212 is the height of the containing cavity M in the pole column 122. The greater the distance d1 between the top wall of the pole column 122 and the top surface of the upper shell 1212, the greater the volume of the tab 112 that can be accommodated, and the more space occupied by the pole column 122 and the tab 112. Reducing the distance d1 between the top wall of the pole column 122 and the top surface of the upper shell 1212 reduces the space occupied by the pole column 122 and the tab 112, compresses the space ratio of the pole column 122 and the tab 112, and improves the energy density of the battery 100.

[0026] The distance between the bottom surface of the upper shell 1212 and the top surface of the core pack body 111 is d2, and d2≤10 mm. Optionally, d2 is 10 mm, 8 mm, 7 mm, or 5 mm, etc. It can be understood that the greater the distance d2 between the bottom surface of the upper shell 1212 and the top surface of the core pack body 111, the greater the gap between the top cover assembly 120 and the core pack body 111. Reducing the distance d2 between the bottom surface of the upper shell 1212 and the top surface of the core pack body 111 compresses the space ratio of the tab 112, thereby improving the energy density of the battery 100.

[0027] Please refer to Fig. 2 again, in the embodiment, the tab 112 is connected to the top wall of the pole 122, and the connection mode is welding. The tab 112 and the top wall of the pole 122 are welded to form a first welding part W1. Specifically, the tab 112 includes a connecting segment 1121, a bending segment 1122 and an extending segment 1123. The connecting segment 1121 is connected to the core pack body 111, and the bending segment 1122 and the extending segment 1123 are sequentially connected to the connecting segment 1121. The extending segment 1123 at the end of the tab 112 away from the core pack body 111 is connected to the top wall of the pole 122, and the first welding part W1 is located in the extending segment 1123. The tab 112 is connected to the core pack body 111 through the connecting segment 1121, so as to realize the connection between the connecting segment 1121 of the tab 112 and the pole piece; then the tab 112 is extended and accommodated in the accommodating cavity M of the pole 122 through the bending segment 1122 and the extending segment 1123, and the bending segment 1122 and the extending segment 1123 of the tab 112 can compress the space occupied by the tab 112 in the accommodating cavity M; finally, the extending segment 1123 at the end is connected to the top wall of the pole 122, so as to realize the connection between the tab 112 and the inner surface of the pole 122, and then realize the electrical connection between the pole piece, the tab 112 and the pole 122.

[0028] In the embodiment, the extending segment 1123 at the end is a rectangular sheet structure, and the top wall of the pole 122 is rectangular, so that the extending segment 1123 can match the shape of the top wall of the pole 122, which is beneficial to increase the welding area. Alternatively, the extending segment 1123 at the end can also be triangular, circular or other shapes, and correspondingly, the top wall of the pole 122 is also triangular or circular, so that the extending segment 1123 can match the shape of the top wall of the pole 122.

[0029] In the embodiment, one pole 122 corresponds to two tabs 112, and the total area of the welding between the two tabs 112 and the pole 122 is S w , S w ≥200mm 2 . That is, in the embodiment, the total welding area is the sum of the welding areas of the two first welding parts W1. Alternatively, S w is 200mm 2 , 400mm 2 , 500mm 2 , 600mm 2 , 800mm 2 , 900mm 2 or 1000mm 2etc. It can be understood that the greater the total area of the weld between the tab 112 and the post 122, the higher the flow capacity between the tab 112 and the post 122 and the smaller the resistance of the weld, thereby effectively reducing the heat generation between the tab 112 and the post 122. However, the weld area of the tab 112 and the post 122 is also limited by the size of the top wall of the post 122, and in this embodiment, the top wall area of the post 122 is 1100mm 2 , i.e. the ratio of the actual weld area to the weldable area of the top wall is greater than or equal to 2 / 11.

[0030] Alternatively, the inner surface of the post 122 includes a top wall and a side wall, and the tab 112 can also be connected to the side wall of the post 122 through a second weld W2. That is, the tab 112 is connected to the top wall of the post 122 through the first weld W1, and / or the tab 112 is connected to the side wall of the post 122 through the second weld W2. In this embodiment, the tab 112 is connected to the top wall of the post 122 through the first weld W1.

[0031] Please refer to FIGS. 4-8, in other embodiments, the tab 112 is not only welded and connected to the top wall of the post 122, but also welded and connected to the side wall of the post 122, thereby increasing the connection area of the tab 112 and the post 122, improving the flow capacity between the tab 112 and the post 122, and reducing the internal resistance of the connection between the tab 112 and the post 122.

[0032] As shown in FIGS. 4, 5 and 6, the battery 100 provided in another embodiment of the present application. The structure of this embodiment is substantially the same as the previous embodiment, the difference is that the structure of the post 122, the tab 112 and the specific connection relationship between the post 122 and the tab 112.

[0033] Since a top cover assembly 120 is correspondingly arranged on the two core packs 110, and one core pack 110 is correspondingly provided with one tab 112, thereby being located in the receiving cavity M of one post 122 of the top cover assembly 120, two tabs 112 respectively connected to two core packs 110 are arranged, as shown in FIG. 4.

[0034] As shown in FIG. 5, accordingly, the two tabs 112 each include a connection segment 1121, a curved segment 1122 and an extension segment 1123. Among them, the curved segment 1122 of one tab 112 is connected to one inner side wall of the post 122, and the extension segment 1123 is connected to the top wall of the post 122; the curved segment 1122 of the other tab 112 is connected to the other inner side wall of the post 122, and the extension segment 1123 is connected to the top wall of the post 122, so that the two tabs 112 are sequentially connected to the inner side wall and the top wall of the post 122, greatly improving the connection area of the tab 112 and the post 122, and reducing the connection internal resistance.

[0035] Optionally, in the embodiment, the included angle a between the top wall of the pole column 122 and the side wall of the pole column 122 is obtuse, as shown in FIG. 6. Specifically, a = 92°, a = 95°, a = 100°, a = 105°, a = 110°, a = 115°, a = 120°, a = 125°, a = 130°, a = 135°, a = 140°, a = 145°, or a = 150°, etc. It can be understood that the tab 112 is arranged by welding the bending segment 1122 and the extending segment 1123 to the side wall and the top wall of the tab 112 respectively, and the top wall and the side wall of the pole column 122 are arranged to abut in an obtuse manner, which facilitates the extension of the tab 112 along the side wall and the top wall. The bending segment 1122 and the extending segment 1123 of the tab 112 also match the shape of the side wall and the top wall of the pole column 122 respectively, so as to increase the contact area of the bending segment 1122 and the side wall of the pole column 122 and the contact area of the extending segment 1123 and the top wall of the pole column 122. Optionally, the top wall of the pole column 122 and the side wall of the pole column 122 are connected by a round corner, so as to reduce the stress at the connection.

[0036] Optionally, in other embodiments, the top wall of the pole column 122 is perpendicular to the side wall of the pole column 122. Such a M-shaped structure of the accommodating cavity is simple in structure and convenient for process manufacturing.

[0037] Optionally, in the embodiment, both of the tabs 112 are connected to the top wall of the pole column 122 by the first welding part W1, and are connected to the side wall of the pole column 122 by the second welding part W2. The total welding area S of the two tabs 112 and the pole column 122 is greater than or equal to 200 mm2. w ≥200mm 2 .

[0038] As shown in FIGS. 7 and 8, the battery 100 provided in another embodiment of the application. The structure of the embodiment is substantially the same as that of the embodiment of FIG. 1, and the difference lies in the specific structure of the tab 112 and the specific connection relationship between the pole column 122 and the tab 112.

[0039] In the embodiment, the battery 100 includes two core packs 110, and a top cover assembly 120 is arranged on the two core packs 110. A plurality of positive tabs 112 of the two core packs 110 are gathered to form a positive tab 112, which is located in the accommodating cavity M of a pole column 122 of the top cover assembly 120. The tab 112 connected to both of the core packs 110 is arranged, as shown in FIG. 7.

[0040] In the embodiment, the tab 112 includes two connecting segments 1121, two bending segments 1122 and two extending segments 1123. The two connecting segments 1121 are connected to the two core package bodies 111 respectively, and the two connecting segments 1121 are folded and connected with the bending segments 1122 and the extending segments 1123 alternately. It can be understood that, by setting the bending segments 1122 and the extending segments 1123 to be connected alternately, the tab 112 is accommodated in the accommodating cavity M of the pole 122 in the form of "S", which greatly reduces the space ratio of the tab 112, so that the tab 112 can be accommodated in the accommodating cavity M with smaller space. Alternatively, the tab 112 can also be accommodated in the accommodating cavity M of the pole 122 in other forms.

[0041] As shown in FIG. 8, one bending segment 1122 is connected with one side wall of the pole 122, the other bending segment 1122 is connected with the other side wall of the pole 122, and the extending segment 1123 at the end is connected with the top wall of the pole 122, so that the tab 112 is connected with the side wall and the top wall of the pole 122 alternately, which greatly increases the connection area of the tab 112 and the pole 122, improves the flow capacity between the tab 112 and the pole 122, and reduces the internal resistance of the connection between the tab 112 and the pole 122. In addition, the two bending segments 1122 are welded with the two side walls of the pole 122 respectively, which fixes the "S" form of the tab 112.

[0042] The above is the description of the battery 100 provided in the embodiment of the application.

[0043] The battery provided in the embodiment of the application includes a core package and a top cover assembly. The top wall and the side wall of the pole in the top cover assembly surround to form an accommodating cavity to accommodate at least part of the tab extending from the core package body, so as to avoid the case that the tab occupies too much space by being connected to the outer surface of the pole. In the case that the volume and weight of the battery are constant, by setting the accommodating cavity in the pole to accommodate at least part of the tab, the space and weight ratio of the tab and the pole in the battery are greatly reduced, so as to improve the volume and weight ratio of the core package body in the battery, and further improve the capacity and energy density of the battery. On the basis of setting the accommodating cavity in the pole to accommodate the tab, the distance between the top wall of the pole and the top surface of the core package body is designed to be less than or equal to 30 mm, which can reduce the space occupied between the pole and the core package body, compress the space ratio of the tab, and thus improve the energy density of the battery.

Claims

1. A battery, comprising: a core pack, the core pack comprising a core pack body and a tab connected to the core pack body; a top cover assembly, the top cover assembly comprising a shell and a post, the shell being disposed on the core pack body, the post being mounted to the shell, a top wall and a side wall of the post enclosing a receiving cavity, at least a portion of the tab being received in the receiving cavity; wherein a distance between the top wall of the post and a top surface of the core pack body is d, and d≤30mm.

2. The battery of claim 1, wherein, the shell comprises an upper shell and a lower shell, the lower shell being disposed on the core pack body, the upper shell being disposed on the lower shell, the post being mounted between the upper shell and the lower shell, a distance between the top wall of the post and a top surface of the lower shell being d1, and d1≤15mm.

3. The battery of claim 2, wherein, a distance between a bottom surface of the lower shell and the top surface of the core pack body is d2, and d2≤10mm.

4. The battery of claim 1, wherein, the tab is connected to the top wall of the post by a first welding portion.

5. The battery of claim 4, wherein, the tab comprises a connecting segment, a bending segment and an extending segment, the connecting segment being connected to the core pack body, the bending segment and the extending segment being connected to the connecting segment in sequence; wherein the extending segment at a distal end of the tab away from the core pack body is connected to the top wall of the post, and the first welding portion is located at the extending segment.

6. The battery of claim 5, wherein, the tab is connected to the side wall of the post by a second welding portion.

7. The battery of claim 6, wherein, the bending segment is connected to the side wall of the post, and the second welding portion is located at the bending segment.

8. The battery of claim 7, wherein, an included angle a between the top wall of the post and the side wall of the post is obtuse.

9. The battery of claim 5, wherein, the bending segment has at least two, and the extending segment has at least two, two bending segments and two extending segments being connected to the connecting segment in sequence.

10. The battery of any one of claims 1-9, wherein, The total welding area of the tab and the pole is S w , S w ≥ 200mm 2 .

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