Battery case and battery case

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery shell and a battery shell, the battery shell comprises a composite shell, a composite cover plate and a composite pole, the composite shell is provided with a first penetrating structure for a pole lug on one side of a pole group to extend out, and the composite cover plate is provided with a second penetrating structure for a pole lug on the other side of the pole group to extend out. And the tab extending out of the accommodating cavity realizes current conduction through the composite pole. The tab extends out of the accommodating cavity to realize current conduction with the composite pole, so that the space occupied by the composite pole and the space for connecting the bent tab with the composite pole are saved, the space utilization rate is improved, the space is provided for increasing the volume of the pole group, the energy density is improved, and the service life of the pole group is prolonged. And by adopting the structural form that the composite shell with the opening in one side is matched with the single composite cover plate, the welding workload of the tab on one side is reduced, and the electrical performance and the mechanical performance of the tab on the side are improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery casing and a battery casing. Background Technology

[0002] For blade batteries, the casing and electrode assembly are indispensable structures, together forming a complete battery. The electrode assembly is the core component of the battery, responsible for storing and releasing electrical energy. It mainly consists of positive electrode material, negative electrode material, electrolyte, and separator. The electrode assembly is the smallest unit of the power battery and also the energy storage unit; it must have a high energy density to store as much energy as possible. The blade battery casing is the container that encloses the electrode assembly. It not only provides physical protection against external environmental influences but also helps dissipate heat and maintain battery stability. Therefore, the performance of the battery casing has a significant impact on battery assembly, safety, and performance.

[0003] Since the blade battery has tabs on both sides, the traditional blade battery casing usually includes a casing body and two cover plate assemblies that are connected to the tabs respectively. The cover plate assembly mainly includes the terminal post, soldering station, cover plate body, upper plastic and lower plastic, etc. The two cover plate assemblies are used to close the openings on both sides of the casing body to form a cavity for storing the electrode assembly. The tabs are bent inside the cavity and connected to the terminal post that extends into the cavity from the cover plate assembly, thereby realizing the conduction of the electrode assembly current.

[0004] The blade battery structure suffers from two main drawbacks. First, a portion of the electrode posts of the side cover plate assemblies needs to extend into the cavity and be welded to the bent tabs inside the cavity. This results in a significant amount of extra space being occupied within the cavity, greatly compressing the usable space of the electrode assembly and leading to low space utilization and energy density. Second, the tabs on both sides of the electrode assembly require welding between the cover plate body and the battery casing, as well as welding between the welding station and the cover plate body and the welding station and the electrode posts. This results in a large amount of welding work on the tab side. The high temperatures generated by this extensive welding work can cause changes in the microstructure of the tab material, thereby affecting its electrical and mechanical properties. This leads to an increase in the resistance of the tabs, which in turn affects the discharge performance and cycle life of the blade battery. Utility Model Content

[0005] The purpose of this utility model is to provide a battery casing and a battery casing with high space utilization, high energy density and strong structural reliability.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] On one hand, a battery housing is provided, the battery housing comprising:

[0008] The composite shell is a hollow shell structure with one side open, and a first through structure for the extension of one side tab of the electrode assembly is provided on the wall opposite to the open side of the composite shell.

[0009] A composite cover plate is provided at the opening of the composite shell and closes the composite shell to form a receiving cavity for accommodating the electrode assembly. The composite cover plate has a second through structure for the electrode tab to extend from the other side of the electrode assembly.

[0010] The composite electrode post is provided on both the side of the composite cover plate away from the electrode group and the side of the composite shell away from the composite cover plate. The electrode tab extending out of the receiving cavity conducts current through the composite electrode post.

[0011] Optionally, the composite housing includes:

[0012] The outer shell body includes a first wall and a plurality of second walls perpendicular to the first wall. The plurality of second walls are arranged around the periphery of the first wall to form a hollow shell structure with one side open. The first wall has a first receiving groove for accommodating the composite pole and a first insertion through hole located in the first receiving groove.

[0013] The first insulating member includes a first upper insulating portion, a first lower insulating portion, and a first plug-in portion. The first upper insulating portion is disposed on the side of the first wall facing away from the pole group and is housed in the first receiving groove. The first lower insulating portion is disposed on the side of the first wall facing the pole group. The first plug-in portion is inserted into the first plug-in through hole and is used to connect the first upper insulating portion and the first lower insulating portion. The first through structure penetrates the first upper insulating portion, the first plug-in portion, and the first lower insulating portion.

[0014] Optionally, the composite cover plate includes:

[0015] The cover plate body has a second receiving groove for accommodating the composite pole and a second insertion through hole located in the second receiving groove on the side opposite to the pole group. The cover plate body is connected to the opening of the outer shell body and closes the outer shell body to form the receiving cavity.

[0016] The second insulating member includes a second upper insulating portion, a second lower insulating portion, and a second insertion portion. The second upper insulating portion is located on the side of the cover plate body away from the pole group and is accommodated in the second receiving groove. The second lower insulating portion is located on the side of the cover plate body facing the pole group. The second insertion portion is inserted into the second insertion through hole and is used to connect the second upper insulating portion and the second lower insulating portion. The second through structure passes through the second upper insulating portion, the second insertion portion, and the second lower insulating portion.

[0017] Optionally, the first lower insulating portion is provided with a first shaping structure on the side facing the pole group that corresponds one-to-one with the first insertion through hole. The first shaping structure is a horn shape with the opening gradually narrowing away from the pole group.

[0018] And / or, the second lower insulating portion is provided with a second shaping structure on the side facing the pole group that corresponds one-to-one with the second insertion through hole, and the second shaping structure is a horn shape with the opening gradually narrowing away from the pole group.

[0019] Optionally, the battery casing further includes a connecting piece;

[0020] The first upper insulating part is provided with a first mounting boss that protrudes in the direction away from the electrode group. A first mounting groove is opened on the side of the first mounting boss away from the electrode group. The connecting piece is disposed in the first mounting groove. The electrode ear that passes through the first through structure is connected to the connecting piece. The connecting piece is connected to the composite electrode post located on the side of the composite shell away from the composite cover plate.

[0021] And / or, the second upper insulating portion is provided with a second mounting boss that protrudes in the direction away from the electrode group, and a second mounting groove is provided on the side of the second mounting boss away from the electrode group. The connecting piece is provided in the second mounting groove, and the electrode lug that passes through the second through structure is connected to the connecting piece. The connecting piece is connected to the composite pole located on the side of the cover plate body away from the electrode group.

[0022] Optionally, the composite pole includes a pole body, a welding ring, and a third insulating component. The third insulating component is injection molded between the pole body and the welding ring to insulate and connect the pole body and the welding ring into a single unit. The pole body is connected to the connecting piece.

[0023] Optionally, the connecting piece has a connecting boss protruding along the side of the pole body facing the pole body, and the pole body is connected to the connecting boss.

[0024] Optionally, the battery casing further includes a sealing element, wherein the sealing element disposed in the first receiving groove is sandwiched between the terminal body and the casing body, and the sealing element disposed in the second receiving groove is sandwiched between the terminal body and the cover plate body.

[0025] Optionally, the battery casing further includes an insulating protective film and at least one protective side plate connected to the insulating protective film, the insulating protective film covering the surface of the electrode assembly where the tabs are not provided.

[0026] On the other hand, a battery housing is provided, the battery housing including an electrode assembly and a battery housing as described in any of the preceding claims, the electrode assembly being disposed within the battery housing.

[0027] The beneficial effects of this utility model are:

[0028] This utility model provides a battery casing. By creating a first through-structure on the composite casing for the tabs on one side of the electrode assembly to extend out, and a second through-structure on the composite cover plate for the tabs on the other side of the electrode assembly to extend out, the tabs on both sides of the electrode assembly can conduct current through the composite terminal located outside the cavity. This not only eliminates the space occupied by connecting the tabs to the composite terminal and the space occupied by the composite terminal extending into the cavity, reducing the space occupied and improving the space utilization rate, but also provides space for increasing the size of the electrode assembly, thereby increasing the energy density. Furthermore, by adopting a single-sided open composite casing combined with a single composite cover plate, the side of the electrode assembly extending out through the first through-structure of the composite casing requires less welding work, thereby reducing the impact of the high temperature generated by the welding work on the microstructure of the tab on that side, reducing the resistance of the tab on that side, and improving the electrical and mechanical properties of the tab.

[0029] The present invention also provides a battery casing, which is assembled by applying the above-described battery casing assembly method, thereby increasing the volume of the electrode assembly, thereby improving the energy density of the battery casing, increasing the power supply capacity of the battery casing, and improving the overall discharge performance and cycle life of the battery by reducing the impact of welding operations on the electrode tabs. Attached Figure Description

[0030] Figure 1 This is an exploded view of the battery casing provided by this utility model;

[0031] Figure 2 This is a partial structural cross-sectional view of the first wall surface of the composite outer casing in the battery provided by this utility model;

[0032] Figure 3 This is a partial structural cross-sectional view of the composite cover plate in the battery provided by this utility model;

[0033] Figure 4 This is a schematic diagram of the structure of the outer casing body in the battery casing provided by this utility model;

[0034] Figure 5 This is a schematic diagram of the front side of the first insulating component in the battery casing provided by this utility model;

[0035] Figure 6 This is a schematic diagram of the structure of the back of the first insulating component in the battery casing provided by this utility model;

[0036] Figure 7 This is a schematic diagram of the structure of the cover plate body in the battery casing provided by this utility model;

[0037] Figure 8 This is a schematic diagram of the front side of the second insulating component in the battery casing provided by this utility model;

[0038] Figure 9 This is a schematic diagram of the structure of the back side of the second insulating component in the battery casing provided by this utility model.

[0039] In the picture:

[0040] 100. Electrode group; 101. Electrode ear;

[0041] 1. Composite shell; 11. Shell body; 111. First wall surface; 112. Second wall surface; 113. First receiving groove; 114. First insertion through hole; 12. First insulating component; 121. First upper insulating part; 1211. First mounting boss; 1212. First mounting groove; 122. First lower insulating part; 123. First insertion part; 124. First through structure; 125. First shaping structure;

[0042] 2. Composite cover plate; 21. Cover plate body; 211. Second receiving groove; 212. Second insertion through hole; 22. Second insulating component; 221. Second upper insulating part; 2211. Second mounting boss; 2212. Second mounting groove; 222. Second lower insulating part; 223. Second insertion part; 224. Second through structure; 225. Second shaping structure;

[0043] 3. Composite pole; 31. Pole body; 32. Welding ring; 33. Third insulating component;

[0044] 4. Connecting piece; 41. Connecting boss;

[0045] 5. Sealing components;

[0046] 6. Insulating protective film;

[0047] 7. Protective side panels. Detailed Implementation

[0048] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0049] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0050] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0051] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0052] Traditional blade battery structures require not only internal space for bending the tabs, but also space for the cover plate assembly's terminals to extend into the cavity. This results in significant space waste, low space utilization, and limited electrode assembly volume, leading to lower energy density. Furthermore, the extensive welding work required at the tabs on both sides of the electrode assembly generates high temperatures that alter the microstructure of the tab material, affecting its electrical and mechanical properties. This increases the tab resistance, ultimately impacting the blade battery's discharge performance and cycle life.

[0053] Therefore, in order to reduce space waste, improve space utilization, increase the energy density of the electrode assembly, and mitigate the impact of welding operations on the microstructure of the electrode tabs, this embodiment provides a battery casing.

[0054] like Figures 1 to 9 As shown, the battery casing includes a composite casing 1, a composite cover plate 2, and composite terminals 3. The composite casing 1 is a hollow shell structure with one open side. A first through structure 124 is provided on the wall of the composite casing 1 opposite to the open side for the extension of the electrode tab 101 on one side of the electrode assembly 100. The composite cover plate 2 is located at the open side of the composite casing 1 and closes the composite casing 1 to form a receiving cavity for accommodating the electrode assembly 100. A second through structure 224 is provided on the composite cover plate 2 for the extension of the electrode tab 101 on the other side of the electrode assembly 100. Composite terminals 3 are provided on the side of the composite cover plate 2 away from the electrode assembly 100 and on the side of the composite casing 1 away from the composite cover plate 2. The electrode tab 101 extending out of the receiving cavity conducts current through the composite terminals 3.

[0055] By providing a first through-structure 124 on the composite housing 1 for the extension of one side of the electrode group 100's tab 101, and a second through-structure 224 on the composite cover plate 2 for the extension of the other side of the electrode group 100's tab 101, the tabs 101 on both sides of the electrode group 100 can extend out of the receiving cavity and conduct current to the composite pole 3 located outside the receiving cavity. This not only eliminates the space occupied by connecting the tab 101 to the composite pole 3 and the space occupied by the composite pole 3 extending into the receiving cavity, reducing the occupation of internal space and improving space utilization, but also provides space for increasing the size of the electrode group 100, improving energy density. Furthermore, by adopting a single-sided open composite housing 1 combined with a single composite cover plate 2, the side of the electrode group 100 with the tab 101 extending through the first through-structure 124 of the composite housing 1 requires less welding work, thereby reducing the impact of the high temperature generated by the welding work on the microstructure of the tab 101 on that side, reducing the resistance of the tab 101 on that side, and improving the electrical and mechanical properties of the tab 101.

[0056] In this embodiment, the electrode tabs 101 of the electrode assembly 100 include a positive electrode tab on one side and a negative electrode tab on the other side, depending on the polarity. During actual assembly, the positive electrode tab can extend out of the receiving cavity through the first through structure 124 or through the second through structure 224, while the negative electrode tab extends out from the remaining first through structure 124 or second through structure 224.

[0057] Optionally, such as Figure 1 , Figure 2 , Figure 4 , Figure 5As shown, the composite housing 1 includes a housing body 11 and a first insulating member 12. The housing body 11 includes a first wall surface 111 and a plurality of second wall surfaces 112 perpendicular to the first wall surface 111. The plurality of second wall surfaces 112 are arranged around the periphery of the first wall surface 111 to form a hollow housing structure with one side open. The first wall surface 111 has a first receiving groove 113 for accommodating the composite pole post 3 and a first insertion through hole 114 located in the first receiving groove 113. The first insulating member 12 includes a first upper insulating part 121 and a first... The lower insulating part 122 and the first plug-in part 123 are provided. The first upper insulating part 121 is provided on the side of the first wall surface 111 away from the pole group 100 and is housed in the first receiving groove 113. The first lower insulating part 122 is provided on the side of the first wall surface 111 facing the pole group 100. The first plug-in part 123 is inserted into the first plug-in through hole 114 and is used to connect the first upper insulating part 121 and the first lower insulating part 122. The first through structure 124 passes through the first upper insulating part 121, the first plug-in part 123 and the first lower insulating part 122.

[0058] By setting a first insulating member 12 consisting of a first upper insulating part 121, a first lower insulating part 122, and a first plug-in part 123, and by placing the first upper insulating part 121 on the side of the first wall surface 111 of the outer casing 11 away from the pole group 100, placing the first lower insulating part 122 on the side of the first wall surface 111 of the outer casing 11 facing the pole group 100, inserting the first plug-in part 123 into the first plug-in through hole 114, and allowing the first through structure 124 to penetrate the first upper insulating part 121 and the first plug-in part 123, the first insulating member 12 is constructed. The first lower insulating part 122 communicates with the receiving cavity, thereby using the first insulating member 12 to provide insulation protection for both sides of the first wall surface 111 of the outer shell body 11 and the inside of the first insertion through hole 114, and to isolate the electrode tab 101 from the first wall surface 111 of the outer shell body 11. This prevents the electrode tab 101 from directly contacting the first wall surface 111 of the outer shell body 11 when it passes through the first wall surface 111 of the outer shell body 11, which could lead to a short circuit. This improves the insulation protection performance of the electrode tab 101 and ensures the reliability of the structure.

[0059] In this embodiment, the outer shell 11 is an aluminum shell, and the first insulating component 12 is a plastic component directly molded onto the first wall surface 111 of the outer shell 11 through injection molding. Compared with traditional cover plate assemblies, the separate lower insulating component is eliminated, thereby reducing the number of parts and simplifying the assembly process. In addition, in this embodiment, the first upper insulating part 121, the first insertion part 123, and the first lower insulating part 122 are integral structural components formed simultaneously through injection molding. In other embodiments, the first upper insulating part 121, the first insertion part 123, and the first lower insulating part 122 can also be injection molded separately and then inserted into each other, making the first insulating component 12 a separate structural component.

[0060] Optionally, such as Figure 1 , Figure 3 , Figure 7 , Figure 8 As shown, the composite cover plate 2 includes a cover plate body 21 and a second insulating member 22. The cover plate body 21 has a second receiving groove 211 for accommodating the composite electrode post 3 and a second insertion through hole 212 located within the second receiving groove 211 on the side opposite to the electrode assembly 100. The cover plate body 21 is connected to the opening of the outer shell body 11 and closes the outer shell body 11 to form a receiving cavity. The second insulating member 22 includes a second upper insulating portion 221, a second lower insulating portion 222, and a second insertion portion 222. 23. The second upper insulating part 221 is provided on the side of the cover plate body 21 away from the pole group 100 and is housed in the second receiving groove 211. The second lower insulating part 222 is provided on the side of the cover plate body 21 facing the pole group 100. The second plug-in part 223 is inserted into the second plug-in through hole 212 and is used to connect the second upper insulating part 221 and the second lower insulating part 222. The second through structure 224 passes through the second upper insulating part 221, the second plug-in part 223 and the second lower insulating part 222.

[0061] By providing a second insulating member 22 consisting of a second upper insulating part 221, a second lower insulating part 222, and a second insertion part 223, and by placing the second upper insulating part 221 on the side of the cover plate body 21 away from the electrode group 100, placing the second lower insulating part 222 on the side of the cover plate body 21 facing the electrode group 100, and inserting the second insertion part 223 into the second insertion through hole 212, the second insulating member 22 provides insulation protection for both sides of the cover plate body 21 and the interior of the second insertion through hole 212, thereby isolating the electrode tab 101 from the cover plate body 21. This prevents the electrode tab 101 from directly contacting the cover plate body 21 when it extends through the cover plate body 21 to the outside of the receiving cavity, thus avoiding a short circuit. This improves the insulation protection performance of the electrode tab 101 and ensures the reliability of the structure.

[0062] In this embodiment, the cover plate body 21 is a plain aluminum plate, and the second insulating parts 22 are all plastic parts directly molded onto the cover plate body 21 by injection molding. Compared with traditional cover plate assemblies, the separate lower insulating part is eliminated, thereby reducing the number of parts and simplifying the assembly process. In addition, in this embodiment, the second upper insulating part 221, the second insertion part 223, and the second lower insulating part 222 are integrated structural parts formed simultaneously by injection molding. In other embodiments, the second upper insulating part 221, the second insertion part 223, and the second lower insulating part 222 can also be injection molded separately and then inserted into each other, making the second insulating part 22 a separate structural part.

[0063] Optionally, such as Figure 2 , Figure 6As shown, the first lower insulating part 122 has a first shaping structure 125 on the side facing the pole group 100, which corresponds to the first insertion through hole 114. The first shaping structure 125 is a horn shape with the opening gradually narrowing away from the pole group.

[0064] By providing a first shaping structure 125 on the side of the first lower insulating portion 122 facing the electrode group 100, and making the first shaping structure 125 a horn shape with the opening gradually narrowing away from the electrode group 100, the multiple bundled tabs 101 extending from the first through structure 124 on the electrode group 100 are better supported and fixed, the bundled state of each tab 101 is improved, and the problem of short circuit caused inside the battery due to poor bundled effect of the tab 101 is avoided.

[0065] In this embodiment, the first insulating component 12 is a plastic component manufactured by injection molding. On the one hand, because its material is relatively soft, it can avoid hard contact with the tab 101, thus preventing damage to the tab 101. On the other hand, because it also has insulation properties, it improves the insulation protection effect.

[0066] Optionally, such as Figure 2 , Figure 9 As shown, the second lower insulating part 222 has a second shaping structure 225 on the side facing the pole group 100, which corresponds to the second insertion through hole 212. The second shaping structure 225 is a horn shape with the opening gradually narrowing away from the pole group.

[0067] By providing a second shaping structure 225 on the side of the second lower insulating portion 222 facing the electrode assembly 100, and making the second shaping structure 225 a horn shape with the opening gradually narrowing away from the electrode assembly 100, the multiple bundled tabs 101 extending from the second through structure 224 on the electrode assembly 100 are better supported and fixed, the bundled state of each tab 101 is improved, and the problem of short circuit caused inside the battery due to poor bundled effect of the tab 101 is avoided.

[0068] In this embodiment, the second insulating component 22 is a plastic component manufactured by injection molding. On the one hand, because its material is relatively soft, it can avoid hard contact with the tab 101, thus preventing damage to the tab 101. On the other hand, because it also has insulation properties, it improves the insulation protection effect.

[0069] Optionally, such as Figure 1 , Figure 2 , Figure 3 , Figure 5 , Figure 8 As shown, the battery casing also includes a connecting piece 4.

[0070] The first upper insulating part 121 is provided with a first mounting boss 1211 that protrudes in the direction away from the electrode group 100. The first mounting boss 1211 is provided with a first mounting groove 1212 on the side away from the electrode group 100. The connecting piece 4 is provided in the first mounting groove 1212. The electrode tab 101 that passes through the first through structure 124 is connected to the connecting piece 4. The connecting piece 4 is connected to the composite electrode post 3 located on the side of the composite shell 1 away from the composite cover plate 2.

[0071] And / or, the second upper insulating part 221 is provided with a second mounting boss 2211 that protrudes in the direction away from the electrode group 100. The second mounting boss 2211 has a second mounting groove 2212 on one side away from the electrode group 100. The connecting piece 4 is disposed in the second mounting groove 2212. The electrode lug 101 that passes through the second through structure 224 is connected to the connecting piece 4. The connecting piece 4 is connected to the composite electrode post 3 located on the side of the cover plate body 21 away from the electrode group 100.

[0072] By setting the connecting piece 4 and first connecting the tab 101 to the connecting piece 4, and then connecting the connecting piece 4 to the composite pole 3, welding operations are not only facilitated, but the connecting piece 4 also pre-fixes the position of the tab 101, ensuring the accuracy of the tab 101's position during subsequent operations and preventing the tab 101 from shifting and affecting the current conduction between the tab 101 and the composite pole 3. Furthermore, the connecting piece 4 is limited by the first mounting groove 1212 on the first mounting boss 1211 and the second mounting groove 2212 on the second mounting boss 2211, thereby ensuring the accuracy of the connecting piece 4's position.

[0073] In this embodiment, the shapes of the first mounting groove 1212 and the second mounting groove 2212 are adapted to the shape of the connecting piece 4. The shape of the connecting piece 4 can be circular, elliptical or polygonal, etc., and its specific shape is adjusted based on facilitating welding of the same electrode tab 101.

[0074] Optionally, such as Figure 1 , Figure 2 , Figure 3 As shown, the composite pole 3 includes a pole body 31, a welding ring 32, and a third insulating component 33. The third insulating component 33 is injection molded between the pole body 31 and the welding ring 32 to insulate and connect the pole body 31 and the welding ring 32 into one piece. The pole body 31 is connected to the connecting piece 4.

[0075] By injection molding the third insulating component 33 between the electrode body 31 and the welding ring 32, the electrode body 31 and the welding ring 32 are connected as one unit. On the one hand, this reduces the number of parts during assembly, shortens the assembly time, and improves the assembly efficiency. On the other hand, since the third insulating component 33 is a plastic part formed by injection molding, it achieves an insulated connection between the electrode body 31 and the welding ring 32, which has high insulation protection performance and prevents the electrode body 31 from communicating with the outer shell body 11 or the cover plate body 21 through the welding ring 32, thus avoiding the problem of short circuit.

[0076] In this embodiment, the electrode body 31 is made of different materials depending on the polarity of the tab 101. When the electrode body 31 is connected to the positive tab, the electrode body 31 is made of pure aluminum. When the electrode body 31 is connected to the negative tab, the electrode body 31 is made of copper-aluminum composite material. Compared with the electrode body 31 made of pure copper, this effectively reduces the manufacturing cost of the electrode body 31 connected to the negative tab.

[0077] Optionally, such as Figure 2 , Figure 3 As shown, the connecting piece 4 has a connecting boss 41 protruding from the pole body 31 on the side facing the pole body 31, and the pole body 31 is connected to the connecting boss 41. By providing the connecting boss 41 on the side of the connecting piece 4 facing the pole body 31, it is convenient to weld the connecting piece 4 to the pole body 31. The size and shape of the connecting boss 41 can be freely set according to requirements, as long as there is sufficient welding area between the connecting boss 41 and the pole body 31. In this embodiment, the connecting boss 41 is a frustum.

[0078] In addition, the connecting piece 4 is made of different materials depending on the polarity of the tab 101. When the connecting piece 4 is connected to the positive tab, the connecting piece 4 is made of pure aluminum. When the connecting piece 4 is connected to the negative tab, the connecting piece 4 is made of copper-aluminum composite material. Compared with the connecting piece 4 made of pure copper, the manufacturing cost of the connecting piece 4 connected to the negative tab is effectively reduced.

[0079] The tab 101 connected to the connecting piece 4 can be connected to the side of the connecting piece 4 facing the pole group 100 or the side of the connecting piece 4 away from the pole group 100. When the tab 101 is connected to the side of the connecting piece 4 facing the pole group 100, the length of the tab 101 can be effectively shortened, thereby improving the efficiency of current transmission. When the tab 101 is connected to the side of the connecting piece 4 away from the pole group 100, the tab 101 is exposed to the outside, which facilitates the welding operation between the tab 101 and the connecting piece 4, reduces the difficulty of the welding operation, and improves the welding efficiency.

[0080] Optionally, such as Figure 1 , Figure 2 , Figure 3, Figure 4 , Figure 7 As shown, the battery casing also includes a sealing element 5. The sealing element 5, located in the first receiving groove 113, is sandwiched between the terminal body 31 and the casing body 11. The sealing element 5, located in the second receiving groove 211, is sandwiched between the terminal body 31 and the cover plate body 21. By providing the sealing element 5 sandwiched between the terminal body 31 and the casing body 11 in the first receiving groove 113, and the sealing element 5 sandwiched between the terminal body 31 and the cover plate body 21 in the second receiving groove 211, the gaps between the terminal body 31 and the casing body 11, and between the terminal body 31 and the cover plate body 21, can be filled and sealed, preventing electrolyte leakage. In this embodiment, the sealing element 5 is made of rubber.

[0081] Optionally, such as Figure 1 , Figure 2 , Figure 3 As shown, the battery casing also includes an insulating protective film 6 and at least one protective side plate 7 connected to the insulating protective film 6. The insulating protective film 6 covers the surface of the electrode assembly 100 where there are no tabs 101. By covering the surface of the electrode assembly 100 where there are no tabs 101 with the insulating protective film 6 connected to at least one protective side plate 7, the surface of the electrode assembly 100 where there are no tabs 101 is protected.

[0082] In this embodiment, the insulating protective film 6 is a polyester film, and the number of protective side plates 7 can be one, two, three, or four, depending on the different protective requirements. In this embodiment, a total of four protective side plates 7 are provided. Before the electrode assembly 100 is covered with the polyester film, four protective side plates 7 are heat-fused onto the polyester film, so that when the polyester film is covered on the electrode assembly 100, it provides four-sided protection for the electrode assembly 100, avoiding damage when the electrode assembly 100 is installed in the housing and reducing the product yield. The shape of the protective side plates 7 is adapted to the surface of the electrode assembly 100 where there are no tabs 101.

[0083] In this embodiment, as Figure 1 As shown, a battery casing is also provided, which includes an electrode assembly 100 and the aforementioned battery casing, with the electrode assembly 100 disposed within the battery casing. By assembling the battery casing using the aforementioned battery casing assembly method, the volume of the electrode assembly 100 is further increased, thereby improving the energy density of the battery casing, increasing its power supply capacity, and improving the overall battery discharge performance and cycle life by reducing the impact of welding operations on the electrode tabs.

[0084] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery casing, characterized in that, The battery casing includes: The composite shell is a hollow shell structure with one side open, and the wall opposite to the open side of the composite shell has a first through structure for the pole tab of one side of the pole group to extend out. A composite cover plate is provided at the opening of the composite shell and closes the composite shell to form a receiving cavity for accommodating the electrode assembly. The composite cover plate has a second through structure for the electrode tab to extend from the other side of the electrode assembly. The composite electrode post is provided on both the side of the composite cover plate away from the electrode group and the side of the composite shell away from the composite cover plate. The electrode tab extending out of the receiving cavity conducts current through the composite electrode post.

2. The battery casing according to claim 1, characterized in that, The composite housing includes: The outer shell body includes a first wall and a plurality of second walls perpendicular to the first wall. The plurality of second walls are arranged around the periphery of the first wall to form a hollow shell structure with one side open. The first wall has a first receiving groove for accommodating the composite pole and a first insertion through hole located in the first receiving groove. The first insulating member includes a first upper insulating portion, a first lower insulating portion, and a first plug-in portion. The first upper insulating portion is disposed on the side of the first wall facing away from the pole group and is housed in the first receiving groove. The first lower insulating portion is disposed on the side of the first wall facing the pole group. The first plug-in portion is inserted into the first plug-in through hole and is used to connect the first upper insulating portion and the first lower insulating portion. The first through structure penetrates the first upper insulating portion, the first plug-in portion, and the first lower insulating portion.

3. The battery casing according to claim 2, characterized in that, The composite cover plate includes: The cover plate body has a second receiving groove for accommodating the composite pole and a second insertion through hole located in the second receiving groove on the side opposite to the pole group. The cover plate body is connected to the opening of the outer shell body and closes the outer shell body to form the receiving cavity. The second insulating member includes a second upper insulating portion, a second lower insulating portion, and a second insertion portion. The second upper insulating portion is located on the side of the cover plate body away from the pole group and is accommodated in the second receiving groove. The second lower insulating portion is located on the side of the cover plate body facing the pole group. The second insertion portion is inserted into the second insertion through hole and is used to connect the second upper insulating portion and the second lower insulating portion. The second through structure passes through the second upper insulating portion, the second insertion portion, and the second lower insulating portion.

4. The battery casing according to claim 3, characterized in that, The first lower insulating part has a first shaping structure on the side facing the pole group that corresponds one-to-one with the first insertion through hole. The first shaping structure is a horn shape with the opening gradually narrowing away from the pole group. And / or, the second lower insulating portion is provided with a second shaping structure on the side facing the pole group that corresponds one-to-one with the second insertion through hole, and the second shaping structure is a horn shape with the opening gradually narrowing away from the pole group.

5. The battery casing according to claim 4, characterized in that, The battery casing also includes a connecting piece; The first upper insulating part is provided with a first mounting boss that protrudes in the direction away from the electrode group. A first mounting groove is opened on the side of the first mounting boss away from the electrode group. The connecting piece is disposed in the first mounting groove. The electrode ear that passes through the first through structure is connected to the connecting piece. The connecting piece is connected to the composite electrode post located on the side of the composite shell away from the composite cover plate. And / or, the second upper insulating portion is provided with a second mounting boss that protrudes in the direction away from the electrode group, and a second mounting groove is provided on the side of the second mounting boss away from the electrode group. The connecting piece is provided in the second mounting groove, and the electrode lug that passes through the second through structure is connected to the connecting piece. The connecting piece is connected to the composite pole located on the side of the cover plate body away from the electrode group.

6. The battery casing according to claim 5, characterized in that, The composite pole includes a pole body, a welding ring, and a third insulating component. The third insulating component is injection molded between the pole body and the welding ring to insulate and connect the pole body and the welding ring into a single unit. The pole body is connected to the connecting piece.

7. The battery casing according to claim 6, characterized in that, The connecting piece has a connecting boss that protrudes from the pole body on the side facing the pole body, and the pole body is connected to the connecting boss.

8. The battery casing according to claim 7, characterized in that, The battery casing also includes a sealing element. The sealing element disposed in the first receiving groove is sandwiched between the terminal body and the casing body, and the sealing element disposed in the second receiving groove is sandwiched between the terminal body and the cover plate body.

9. The battery casing according to claim 1, characterized in that, The battery casing also includes an insulating protective film and at least one protective side plate connected to the insulating protective film, the insulating protective film covering the surface of the electrode assembly where the tabs are not provided.

10. A battery casing, characterized in that, The battery casing includes an electrode assembly and a battery casing as described in any one of claims 1-9, wherein the electrode assembly is disposed within the battery casing.

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