Battery shell and battery

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery shell and a battery, the battery shell comprises a shell body and a cover plate assembly, the shell body is a hollow shell mechanism with an opening at one side, the cover plate assembly comprises a cover plate body, a first insulating part and a composite pole, the cover plate body is arranged at the opening of the shell body and seals the shell body, and the composite pole is arranged on the first insulating part. The cover plate body is used for forming an accommodating cavity for accommodating a pole group, the cover plate body is provided with a first penetrating structure through which a lug extends out of the accommodating cavity, the first insulating part is arranged on the cover plate body in an injection molding manner and is used for isolating the cover plate body from the lug, and the composite pole column is arranged on one side, deviating from the pole group, of the cover plate body and realizes current conduction with the lug. Through the arrangement of the first penetrating structure, the tab can realize current conduction with the composite pole located on the outer side of the accommodating cavity through the first penetrating structure, so that the space occupied by the composite pole and the space for connecting the bent tab with the composite pole are saved, the extra space occupation is reduced, the volume of the pole group can be further increased, and the energy density is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery shell and a battery. Background Art

[0002] For prismatic batteries, the battery case and electrode group are indispensable components of the battery, with the electrode group and the battery case together forming a complete battery. The electrode group is the core component of the battery, responsible for storing and releasing electrical energy. The electrode group is primarily composed of positive electrode material, negative electrode material, electrolyte, and separator. The electrode group is the smallest unit of a power battery and serves as the electrical energy storage unit. It must have a high energy density to store as much electrical energy as possible. The battery case is the container that wraps the electrode group. It not only provides physical protection, preventing the electrode group from being affected by the external environment, but also helps dissipate heat from the electrode group, maintaining battery stability. Therefore, the performance of the battery case has a significant impact on the assembly, safety, and performance of the battery.

[0003] Since the electrode group of the square shell battery is in the form of a single-sided electrode ear, the traditional square shell battery shell usually includes a shell body and a cover assembly for closing the shell body to form a accommodating cavity for accommodating the electrode group. The positive electrode ear and the negative electrode ear of the electrode group are respectively connected to the positive electrode column and the negative electrode column on the cover assembly. In order to facilitate the connection between the positive electrode ear and the negative electrode ear and the corresponding positive electrode column and the negative electrode column, usually part of the positive and negative electrode columns are located inside the accommodating cavity and part of them are located outside the accommodating cavity. In order to facilitate the connection between the positive and negative electrode ears and the positive and negative electrode columns extending into the accommodating cavity, the positive and negative electrode ears need to be bent to achieve the connection between the two.

[0004] Since part of the pole of the square shell battery with this structure extends into the interior of the accommodating cavity, and the pole ear needs to be bent and connected to the part of the pole extending into the accommodating cavity, a large amount of additional space needs to be reserved in the accommodating cavity. This not only wastes a lot of space, resulting in extremely low space utilization, but also greatly compresses the space that can be used by the pole group, resulting in a limited volume of the pole group, thereby making the energy density of the square shell battery low and the power supply capacity poor. Utility Model Content

[0005] The purpose of the utility model is to provide a battery casing and a battery, which occupy little extra space, have high space utilization, a large pole group volume, and high energy density.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] In one aspect, a battery housing is provided, wherein the battery housing is used to accommodate an electrode group, and the battery housing comprises:

[0008] A shell body is a single-sided open hollow shell mechanism;

[0009] A cover plate assembly includes a cover plate body, a first insulating piece and a composite pole, the cover plate body is arranged at the opening of the shell body and closes the shell body to form a containing cavity containing the pole group, the pole group in the containing cavity is provided with a tab, the cover plate body is provided with a first penetrating structure for the tab to extend out of the containing cavity, the first insulating piece is injection molded on the cover plate body and is used to insulate the cover plate body from the tab, and the composite pole is arranged on the side of the cover plate body away from the pole group and realizes current conduction with the tab.

[0010] Optionally, the first insulating piece includes an upper insulating part, a lower insulating part and a plug-in part, the upper insulating part is arranged on the side of the cover plate body away from the pole group, the lower insulating part is arranged on the side of the cover plate body facing the pole group, the plug-in part is inserted into the first penetrating structure and is used to connect the upper insulating part and the lower insulating part, and the first insulating piece is also provided with a second penetrating structure penetrating the upper insulating part, the plug-in part and the lower insulating part, and the tab passes through the second penetrating structure and extends out of the containing cavity.

[0011] Optionally, the upper insulating part is provided with a mounting boss protruding away from the pole group, and a containing groove is formed in the mounting boss, and the cover plate assembly further includes a connecting sheet, the connecting sheet is arranged in the containing groove, the tab passing through the second penetrating structure is connected with the connecting sheet, and the connecting sheet is connected with the composite pole.

[0012] Optionally, the tab is connected to the side of the connecting sheet facing the pole group, or the tab is connected to the side of the connecting sheet facing the composite pole.

[0013] Optionally, the side of the lower insulating part facing the pole group is provided with a shaping structure corresponding to the second penetrating structure, and the shaping structure is a horn type with an opening gradually narrowing away from the pole group.

[0014] Optionally, the side of the cover plate body away from the pole group is also provided with a mounting groove, the first penetrating structure is arranged in the mounting groove, the composite pole includes a pole body, a welding ring and a second insulating piece, the second insulating piece is injection molded between the pole body and the welding ring to insulate and connect the pole body and the welding ring into one body, the welding ring is welded in the mounting groove, and the pole body is connected with the connecting sheet.

[0015] Optionally, a connecting boss is arranged on one side of the connecting piece, which protrudes towards the pole body, and the pole body is welded with the connecting boss.

[0016] Optionally, the cover plate assembly further comprises a sealing member, which is arranged in the mounting groove and clamped between the pole body and the cover plate body.

[0017] Optionally, the battery shell further comprises a bottom supporting plate, the outside of the pole group is covered with an insulating film, and the bottom supporting plate is arranged at the surface opposite to the tab of the pole group and is connected with the insulating film by heat melting.

[0018] In another aspect, a battery is also provided, which comprises a pole group and the battery shell as claimed in any one of the above, and the pole group is arranged in the battery shell.

[0019] The battery shell has the following beneficial effects:

[0020] The battery shell has the following beneficial effects:

[0021] The battery provided by the utility model has the following beneficial effects: the battery shell is applied, so that the additional space is reduced, the space available for the pole group is enlarged, the volume of the pole group is increased, the battery has higher energy density and stronger power supply capacity. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a structural exploded view of the battery provided by the utility model;

[0023] Figure 2 is a partial front view structural cross-sectional view of the battery provided by the utility model;

[0024] Figure 3 is a partial side view structural cross-sectional view of the battery provided by the utility model;

[0025] Figure 4 is a structural schematic view of the cover plate body in the battery shell provided by the utility model;

[0026] Figure 5It is the structural schematic view of the first insulating piece in the battery shell provided by the utility model.

[0027] Figure 6 It is Figure 5 The structure enlarged view of A part in the middle.

[0028] In the figure,

[0029] 100, pole group; 101, pole lug; 200, insulating film;

[0030] 1, shell body;

[0031] 2, cover plate assembly; 21, cover plate body; 211, first through structure; 212, mounting groove; 22, first insulating piece; 221, upper insulating part; 222, lower insulating part; 223, plug-in part; 224, second through structure; 225, mounting boss; 226, accommodating groove; 227, shaping structure; 23, composite pole; 231, pole body; 232, welding ring; 233, second insulating piece; 24, connecting sheet; 241, connecting boss; 25, sealing piece;

[0032] 3, bottom supporting plate. DETAILED DESCRIPTION

[0033] The utility model will be further explained in detail in combination with the drawings and examples. It can be understood that the specific examples described here are only used to explain the utility model, and not limit the utility model. In addition, it needs to be explained that in order to facilitate the description, only the part related to the utility model is shown in the drawings, not all structures.

[0034] In the description of the utility model, unless there is explicit definition and limitation, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral;It can be mechanical connection, or electrical connection;It can be directly connected, or indirectly connected through intermediate medium, it can be the communication inside two elements or the interaction of two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0035] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0036] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0037] When connecting the tab and the electrode group of the square shell battery, a part of the electrode column needs to extend into the interior of the accommodating cavity, and the tab needs to be bent and connected to the part of the electrode column extending into the interior of the accommodating cavity, so a large amount of extra space needs to be reserved in the accommodating cavity, which not only wastes a lot of space and leads to extremely low space utilization, but also greatly compresses the space that can be used by the electrode group, resulting in a limited volume of the electrode group, thereby making the energy density of the square shell battery low and the power supply capacity poor.

[0038] Therefore, in order to reduce the extra space occupied, improve the utilization of space, expand the space available for the electrode group, increase the energy density, and enhance the power supply capacity, this embodiment provides a battery housing for accommodating the electrode group.

[0039] like Figures 1 to 6 As shown, the battery shell includes a shell body 1 and a cover assembly 2. The shell body 1 is a hollow shell structure with a single-side opening. The cover assembly 2 includes a cover body 21, a first insulating member 22 and a composite pole 23. The cover body 21 is arranged at the opening of the shell body 1 and closes the shell body 1 to form an accommodating cavity for accommodating the pole group 100. The pole group 100 located in the accommodating cavity is provided with a pole ear 101. The cover body 21 is provided with a first through structure 211 for the pole ear 101 to extend out of the accommodating cavity. The first insulating member 22 is injection-molded on the cover body 21 and is used to isolate the cover body 21 from the pole ear 101. The composite pole 23 is arranged on the side of the cover body 21 away from the pole group 100 and realizes current conduction with the pole ear 101.

[0040] By providing a first through-hole structure 211 on the cover body 21, when realizing the conduction of current between the pole ear 101 and the composite pole 23, the pole ear 101 can extend out of the accommodating cavity through the first through-hole structure 211 and realize the conduction of current with the composite pole 23 located outside the accommodating cavity. This not only saves the space occupied by the composite pole 23 and the space where the pole ear 101 is bent and connected to the composite pole 23, reduces the additional space occupied and improves the space utilization, but also can further increase the volume of the pole group 100 on the basis of maintaining the original structural design, so that the battery has a higher energy density and a stronger power supply capacity.

[0041] Among them, the number of first penetrating structures 211 is determined according to the number of pole groups 100 accommodated in the accommodating cavity. In this embodiment, two pole groups 100 are provided in the accommodating cavity. Therefore, four first penetrating structures 211 are provided on the cover body 21 for the pole tabs 101 to extend out of the accommodating cavity, wherein two pole tabs 101 of the same polarity are connected to the same composite pole 23, thereby reducing the number of components and making the structure more compact.

[0042] Optionally, Figure 3 、 Figure 5 、 Figure 6 As shown, the first insulating member 22 includes an upper insulating portion 221, a lower insulating portion 222 and a plug-in portion 223. The upper insulating portion 221 is provided on the side of the cover body 21 away from the pole group 100, and the lower insulating portion 222 is provided on the side of the cover body 21 facing the pole group 100. The plug-in portion 223 is inserted into the first through-structure 211 and is used to connect the upper insulating portion 221 and the lower insulating portion 222. The first insulating member 22 is also provided with a second through-structure 224 that penetrates the upper insulating portion 221, the plug-in portion 223 and the lower insulating portion 222. The pole ear 101 passes through the second through-structure 224 and extends out of the accommodating cavity.

[0043] By setting a first insulating part 22 consisting of an upper insulating part 221, a lower insulating part 222 and a plug-in part 223, and making the upper insulating part 221 arranged on the side of the cover body 21 away from the pole group 100, and making the lower insulating part 222 arranged on the side of the cover body 21 facing the pole group 100, and making the plug-in part 223 inserted into the first through-hole structure 211, the first insulating part 22 is used to achieve insulation protection for both sides of the cover body 21 and the inside of the first through-hole structure 211, and isolate the pole ear 101 and the cover body 21, so as to avoid direct contact between the pole ear 101 and the cover body 21 when passing through the cover body 21, resulting in a short circuit, thereby ensuring safety and protection.

[0044] In this embodiment, the cover body 21 is a plain aluminum plate, and the first insulating member 22 is a plastic member directly molded onto the cover body 21 through an injection molding process. Compared to the conventional cover assembly 2, the separate lower insulating member is eliminated, thereby eliminating the step of assembling the lower insulating member with the cover body 21 during assembly, simplifying the assembly process and improving assembly efficiency. In addition, in this embodiment, the upper insulating portion 221, the plug portion 223, and the lower insulating portion 222 are an integrated structural member formed simultaneously through an injection molding process. In other embodiments, the upper insulating portion 221, the plug portion 223, and the lower insulating portion 222 can also be separately injection molded and then plugged into each other, making the first insulating member 22 a split structural member.

[0045] Alternatively, as Figure 6 As shown, the upper insulating portion 221 is provided with a mounting boss 225 protruding in a direction away from the pole group 100, and a receiving groove 226 is opened on the mounting boss 225. The cover plate assembly 2 also includes a connecting piece 24, which is arranged in the receiving groove 226. The pole ear 101 passing through the second through structure 224 is connected to the connecting piece 24, and the connecting piece 24 is connected to the composite pole 23.

[0046] By connecting the tab 101 to the connecting piece 24, and then connecting the connecting piece 24 to the composite pole 23, not only is welding easier, but the tab 101 can also be fixed in position in advance using the connecting piece 24, ensuring the accuracy of the tab 101 position during subsequent operations and preventing the tab 101 from moving, which could affect the conduction of current between the tab 101 and the composite pole 23. Furthermore, a receiving groove 226 for accommodating the connecting piece 24 is provided on the mounting boss 225 to limit the position of the connecting piece 24, thereby ensuring the accuracy of the position of the connecting piece 24.

[0047] In this embodiment, the shape of the receiving groove 226 is adapted to the shape of the connecting piece 24 . The shape of the connecting piece 24 can be circular, elliptical or polygonal, etc. Its specific shape is adjusted based on the convenience of welding with the tab 101 .

[0048] Optionally, the tab 101 is connected to the side of the connecting piece 24 facing the electrode group 100. By connecting the tab 101 to the side of the connecting piece 24 facing the electrode group 100, the length of the tab 101 is shortened, thereby improving the efficiency of current transmission.

[0049] Alternatively, as Figure 2 、 Figure 3As shown, the tab 101 is connected to the side of the connecting piece 24 facing the composite pole 23, so that the tab 101 is connected to the side of the connecting piece 24 facing the composite pole 23, so that when the tab 101 is connected to the composite pole 23, the tab 101 is exposed to the outside, thereby facilitating the welding operation between the tab 101 and the connecting piece 24, reducing the difficulty of the welding operation, and improving the welding efficiency.

[0050] Alternatively, as Figure 3 As shown, a shaping structure 227 corresponding one-to-one with the second penetrating structure 224 is provided on the side of the lower insulating portion 222 facing the electrode assembly 100. The shaping structure 227 is a trumpet-shaped structure with its opening gradually narrowing as it moves away from the electrode assembly 100. By providing the shaping structure 227 on the side of the lower insulating portion 222 facing the electrode assembly 100 and making the shaping structure 227 a trumpet-shaped structure with its opening gradually narrowing as it moves away from the electrode assembly 100, the multiple converged tabs 101 on the electrode assembly 100 are better supported and fixed, improving the convergence of the tabs 101 and avoiding the problem of short circuits within the battery due to poor convergence of the tabs 101.

[0051] Alternatively, as Figure 1 、 Figure 3 、 Figure 4 As shown, a mounting groove 212 is further provided on the side of the cover body 21 facing away from the pole group 100. The first through-structure 211 is provided in the mounting groove 212. The composite pole 23 includes a pole body 231, a welding ring 232, and a second insulating member 233. The second insulating member 233 is injection-molded between the pole body 231 and the welding ring 232 to insulate and connect the pole body 231 and the welding ring 232 into one piece. The welding ring 232 is welded in the mounting groove 212, and the pole body 231 is connected to the connecting piece 24.

[0052] By injection molding the second insulating member 233 between the pole body 231 and the welding ring 232, the pole body 231 and the welding ring 232 are connected as one. On the one hand, the number of parts during assembly is reduced, the assembly time is shortened, and the assembly efficiency is improved. On the other hand, since the second insulating member 233 is a plastic part formed by an injection molding process, an insulated connection between the pole body 231 and the welding ring 232 is achieved, which has high insulation protection performance and avoids the pole body 231 from being connected to the cover body 21 through the welding ring 232, thereby preventing the problem of short circuit.

[0053] In this embodiment, the pole body 231 is made of different materials according to the different polarities of the pole ear 101. When the pole body 231 is connected to the positive pole ear, the pole body 231 is made of pure aluminum. When the pole body 231 is connected to the negative pole ear, the pole body 231 is made of a copper-aluminum composite material. Compared with the pole body 231 made of pure copper, the production cost of the pole body 231 connected to the negative pole ear is effectively reduced.

[0054] Alternatively, as Figure 3 As shown, the side of the connecting piece 24 facing the pole body 231 is provided with a connecting boss 241 that protrudes along and near the pole body 231. The pole body 231 is welded to the connecting boss 241. The provision of the connecting boss 241 on the side of the connecting piece 24 facing the pole body 231 facilitates welding of the connecting piece 24 and the pole body 231. The size and shape of the connecting boss 241 can be freely set according to needs, as long as there is sufficient welding area between the connecting boss 241 and the pole body 231. In this embodiment, the connecting boss 241 is a frustum.

[0055] In addition, the connecting piece 24 is made of different materials according to the different polarities of the electrode tab 101. When the connecting piece 24 is connected to the positive electrode tab, the connecting piece 24 is made of pure aluminum. When the connecting piece 24 is connected to the negative electrode tab, the connecting piece 24 is made of copper-aluminum composite material. Compared with the connecting piece 24 made of pure copper, the manufacturing cost of the connecting piece 24 connected to the negative electrode tab is effectively reduced.

[0056] Alternatively, as Figure 1 、 Figure 3 As shown, the cover plate assembly 2 further includes a seal 25, which is disposed in the mounting groove 212 and is sandwiched between the pole body 231 and the cover plate body 21. By disposing the seal 25 between the composite pole 23 and the cover plate body 21, the gap between the composite pole 23 and the cover plate body 21 is filled and sealed to prevent leakage of the electrolyte.

[0057] Alternatively, as Figure 1 As shown, the battery case further includes a bottom support plate 3. The outer side of the electrode group 100 is covered with an insulating film 200. The bottom support plate 3 is provided on the surface of the electrode group 100 opposite the electrode tab 101 and is heat-fused to the insulating film 200. By heat-fusion bonding the bottom support plate 3 to the insulating film 200, when the insulating film 200 is coated on the electrode group 100, the bottom support plate 3 can cover the surface of the electrode group 100 opposite the electrode tab 101. When the electrode group 100 is placed into the case, the bottom support plate 3 provides protection and prevents scratches during insertion.

[0058] In this embodiment, if Figure 1 As shown, a battery is also provided, comprising an electrode assembly 100 and the aforementioned battery housing, wherein the electrode assembly 100 is disposed within the battery housing. By utilizing the aforementioned battery housing, the battery reduces the need for additional space, expands the space available for the electrode assembly 100, and increases the volume of the electrode assembly 100, thereby achieving not only a higher energy density but also a stronger power supply capability.

[0059] Obviously, the above embodiments of the present application are merely examples for clearly illustrating the present application, and are not intended to limit the implementation modes of the present application. For those skilled in the art, various obvious changes, re-adjustments and replacements can be made without departing from the protection scope of the present application. Here, it is not necessary and also impossible to enumerate all the implementation modes. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application claim.

Claims

1. A battery housing, wherein the battery housing is used to accommodate an electrode group, characterized in that: The battery housing comprises: The outer shell body is a hollow shell structure with a single-side opening; A cover plate assembly, the cover plate assembly includes a cover plate body, a first insulating member and a composite pole. The cover plate body is arranged at the opening of the shell body and closes the shell body to form an accommodating cavity for accommodating the pole group. The pole group located in the accommodating cavity is provided with a pole ear. The cover plate body is provided with a first through-structure for the pole ear to extend out of the accommodating cavity. The first insulating member is injection-molded on the cover plate body and is used to isolate the cover plate body from the pole ear. The composite pole is arranged on the side of the cover plate body away from the pole group and realizes current conduction with the pole ear.

2. The battery housing according to claim 1, wherein: The first insulating member includes an upper insulating portion, a lower insulating portion and a plug-in portion. The upper insulating portion is arranged on the side of the cover body facing away from the pole group, and the lower insulating portion is arranged on the side of the cover body facing the pole group. The plug-in portion is inserted into the first through-hole structure and is used to connect the upper insulating portion and the lower insulating portion. The first insulating member also has a second through-hole structure that passes through the upper insulating portion, the plug-in portion and the lower insulating portion. The pole ear passes through the second through-hole structure and extends out of the accommodating cavity.

3. The battery housing according to claim 2, wherein: The upper insulating portion is provided with a mounting boss protruding in a direction away from the pole group, and a receiving groove is provided on the mounting boss. The cover plate assembly also includes a connecting piece, which is arranged in the receiving groove. The pole ear passing through the second through-structure is connected to the connecting piece, and the connecting piece is connected to the composite pole.

4. The battery housing according to claim 3, wherein: The pole tab is connected to a side of the connecting piece facing the pole group, or the pole tab is connected to a side of the connecting piece facing the composite pole.

5. The battery housing according to claim 2, wherein: A shaping structure corresponding to the second penetrating structure is provided on a side of the lower insulating portion facing the pole group. The shaping structure is a trumpet-shaped structure with an opening gradually shrinking in a direction away from the pole group.

6. The battery housing according to claim 3, wherein: A mounting groove is further provided on the side of the cover body facing away from the pole group. The first penetrating structure is provided in the mounting groove. The composite pole includes a pole body, a welding ring and a second insulating member. The second insulating member is injection-molded between the pole body and the welding ring to insulate and connect the pole body and the welding ring into one piece. The welding ring is welded in the mounting groove, and the pole body is connected to the connecting piece.

7. The battery housing according to claim 6, wherein: A connecting boss is provided on one side of the connecting piece facing the pole body and is raised close to the pole body, and the pole body is welded to the connecting boss.

8. The battery housing according to claim 6, wherein: The cover plate assembly further includes a sealing member, which is disposed in the mounting groove and is sandwiched between the pole body and the cover plate body.

9. The battery housing according to claim 1, wherein: The battery housing further comprises a bottom supporting plate, the outer side of the electrode group is covered with an insulating film, the bottom supporting plate is arranged on the surface of the electrode group opposite to the electrode tab and is thermally melt-connected with the insulating film.

10. A battery, characterized in that The battery comprises a pole group and a battery casing according to any one of claims 1 to 9, wherein the pole group is arranged in the battery casing.

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