Single cells and battery packs

Abstract

The present application relates to the technical field of energy storage devices, and discloses a single cell and a battery pack. The single cell includes a bare cell, a shell, and two pole units. The shell includes a box body and a cover plate. The box body includes a bottom wall and side walls. The bottom wall and the side walls enclose a cavity with an opening. The bare cell has pole ears extending from both ends along the length direction. The bare cell is accommodated in the cavity. The cover plate can cover the opening and be sealed with the box body. The bare cell can enter the cavity from the opening. The bottom wall of the box body is located on one side in the thickness direction of the bare cell, and the opening of the box body is located on the opposite side of the bottom wall. Therefore, the bare cell can be loaded into the cavity along the thickness direction from the opening of the box body, and then the cover plate can be sealed. Therefore, the bare cell has a small entry stroke into the shell during assembly, which reduces the difficulty of assembly and solves the problem of the bare cell being easily scratched during the entry process, thereby ensuring the stability and safety of the battery. The battery pack with the above-mentioned single cell also has the above-mentioned advantages.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage devices, and in particular to a single cell and a battery pack. Background Art

[0002] In battery systems, increasing the length of individual cells and designing them flat and elongated to form a long battery structure can improve battery pack integration efficiency and increase volume space utilization, thereby achieving a battery pack with high volumetric energy density. Current single-cell batteries with long battery structures have openings at both ends of the shell. After the bare cell is inserted into the shell through one end, a top cover and terminals are installed at each end. However, during assembly, the flat and long shell makes it difficult for the bare cell to enter the shell, and the bare cell is easily scratched during the insertion process, making assembly difficult. Summary of the Invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a single battery that can reduce the difficulty of assembly and effectively prevent the bare battery cell from being scratched when it is inserted into the shell.

[0004] The present application also proposes a battery pack comprising the above-mentioned single battery.

[0005] A single cell according to an embodiment of the first aspect of the present application includes:

[0006] A bare battery cell, wherein tabs extend from both ends of the bare battery cell along the length direction;

[0007] The housing comprises a box body and a cover plate, wherein the box body comprises a bottom wall and side walls, wherein the bottom wall and the side walls together form a cavity having an opening, wherein the bare cell is accommodated in the cavity, wherein the bottom wall is located on one side in the thickness direction of the bare cell, and the opening is located on the opposite side of the bottom wall, wherein the opening can allow the bare cell to pass through, and the cover plate can cover the opening and be sealed to the box body;

[0008] Two pole units, mounting portions are respectively provided at positions on the shell corresponding to the two pole tabs, and the pole units are connected to the mounting portions and electrically connected to the pole tabs.

[0009] The single cell battery of the embodiment of the first aspect of the present application has at least the following beneficial effects: the box body forms a cavity with an opening on one side, and the bare battery cell can enter the cavity from the opening; the bottom wall of the box body is located on one side in the thickness direction of the bare battery cell, and the opening of the box body is located on the opposite side of the bottom wall; therefore, the bare battery cell can be loaded into the cavity along the thickness direction from the opening of the box body, and then the cover plate can be sealed; therefore, the bare battery cell has a small entry stroke into the shell during assembly, which reduces the difficulty of assembly and solves the problem of the bare battery cell being easily scratched during the shell entry process, thereby ensuring the stability and safety of the battery.

[0010] According to some embodiments of the present application, the mounting portions are respectively provided at positions on the cover plate corresponding to the two pole ears, the pole unit is connected to the cover plate at the mounting portions, and a groove is provided at the connection between the bottom wall and the side wall of the box body, the groove corresponds to the position of the pole unit and is recessed toward the cavity.

[0011] According to some embodiments of the present application, a groove is provided on the box body at positions corresponding to the two pole ears, the groove is recessed toward the cavity, the groove has a first groove wall facing the cover plate, the mounting portion is provided on the first groove wall, and the pole unit is connected to the box body at the mounting portion.

[0012] According to some embodiments of the present application, the groove has a second groove wall on one side in the length direction of the bare battery cell, and the second groove wall is used to support the bare battery cell.

[0013] According to some embodiments of the present application, a first insulating structure is provided between the box body and the bare battery cell, and a second insulating structure is provided between the cover plate and the bare battery cell. The first insulating structure and the second insulating structure are connected to each other, and the first insulating structure and the second insulating structure are used to insulate the bare battery cell.

[0014] According to some embodiments of the present application, the first insulating structure includes an insulating box, which is sleeved in the box body and located between the bare battery cell and the box body. The insulating box has a connection port on the side facing the cover plate, and the connection port is connected to the second insulating structure; or, the first insulating structure includes a first insulating layer, which is attached to the inner surface of the box body, and the first insulating layer is connected to the second insulating structure.

[0015] According to some embodiments of the present application, the second insulating structure includes an insulating plate, which is located between the cover plate and the bare battery cell, and the insulating plate is connected to the first insulating structure; or, the second insulating structure includes a second insulating layer, which is attached to the side of the cover plate facing the cavity, and the second insulating layer is connected to the first insulating structure.

[0016] According to some embodiments of the present application, the pole unit includes an adapter, a connector and an external conductive terminal, the adapter is located in the cavity and is electrically connected to the pole tab, the external conductive terminal is located outside the cavity and is conductively connected to the adapter, and the adapter and the external conductive terminal are connected to the mounting portion through the connector.

[0017] According to some embodiments of the present application, the adapter includes a first section and a second section, the first section is used to connect the connector, the second section is perpendicular to the extension direction of the tab, and the tab is electrically connected to the second section after being bent.

[0018] A battery pack according to an embodiment of the second aspect of the present application includes a box body and a plurality of single cells according to the embodiment of the first aspect, wherein the single cells are accommodated in the box body.

[0019] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present application is further described below with reference to the accompanying drawings and embodiments, wherein:

[0021] Figure 1 This is a schematic structural diagram of a single cell according to an embodiment of the present application;

[0022] Figure 2 for Figure 1 An exploded schematic diagram of a single battery is shown;

[0023] Figure 3 for Figure 1 AA section view in the figure;

[0024] Figure 4 for Figure 3 A local enlarged schematic diagram of point B in FIG;

[0025] Figure 5 for Figure 1 Schematic diagram of the bare cell, cover plate and terminal unit in the single battery before assembly;

[0026] Figure 6 for Figure 5 Schematic diagram of the structure after the bare cell, cover and pole unit are assembled;

[0027] Figure 7 This is a schematic diagram of the insulation box and the cover before assembly;

[0028] Figure 8 for Figure 7 Schematic diagram of the assembled insulation box and cover plate;

[0029] Figure 9 This is a schematic diagram of the box body and the cover before assembly;

[0030] Figure 10 A schematic diagram of the arrangement of multiple single battery cells according to an embodiment of the present application;

[0031] Figure 11This is a schematic structural diagram of a single cell according to another embodiment of the present application;

[0032] Figure 12 for Figure 11 A schematic structural diagram of the box body in the illustrated embodiment;

[0033] Figure 13 for Figure 11 Schematic diagram from another perspective;

[0034] Figure 14 for Figure 11 An exploded schematic diagram of a single battery is shown;

[0035] Figure 15 for Figure 13 The CC section view in the figure;

[0036] Figure 16 for Figure 15 A local enlarged schematic diagram of point D in FIG.

[0037] Figure 17 for Figure 11 A schematic diagram of the box body and the insulating box in the single battery before assembly;

[0038] Figure 18 for Figure 11 Schematic diagram of the bare cell and adapter in the single battery before assembly;

[0039] Figure 19 for Figure 11 Schematic diagram of the bare cell, box body and pole unit before assembly;

[0040] Figure 20 for Figure 19 Schematic diagram of the structure after the bare battery cell, box body and pole unit are assembled;

[0041] Figure 21 This is a schematic diagram of the box body, cover plate and insulation plate before assembly;

[0042] Figure 22 This is a schematic diagram of the arrangement of multiple single battery cells according to an embodiment of the present application.

[0043] Reference numerals:

[0044] Cover plate 1, second insulating layer 11, mounting portion 12;

[0045] Box body 2, bottom wall 21, side wall 22, opening 23, groove 24, first groove wall 241, second groove wall 242;

[0046] Bare cell 3, tab 31;

[0047] Insulation box 4, first recessed portion 41, first wall 411, second wall 412, second recessed portion 42, connection port 43, welding area 44;

[0048] Pole unit 5, adapter 51, first section 511, second section 512, outer insulating member 52, outer conductive terminal 53, connector 54;

[0049] Insulation board 6. DETAILED DESCRIPTION

[0050] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0051] In the description of this application, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this application.

[0052] In the description of this application, "several" means more than one, and "above," "below," and "within" are understood to include the number itself. The use of terms such as "first," "second," and so on is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0053] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0054] In the description of this application, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0055] The single battery cell with a long battery structure is designed to be long and thin, thus having a long and flat appearance.

[0056] When assembling a conventional single cell battery with a long battery structure, the bare cell is inserted into the shell from one of the two openings in the length direction of the shell. After entering the shell, the tabs at both ends of the bare cell are located at the openings at both ends of the shell to facilitate connection to the top cover and the terminals. However, the cylindrical shell is difficult to manufacture, the cost is high, and the wall thickness is large. In addition, the flat and long shell makes the bare cell have a long entry distance into the shell, and the bare cell is easily scratched during the entry process, making assembly difficult. However, the embodiment of the present application provides a single cell and a battery pack having the single cell, which optimizes the structure of the single cell so that the bare cell can enter the shell along the thickness direction, greatly reducing the entry distance and thus reducing the difficulty of entry.

[0057] Figure 1 This is a schematic structural diagram of a single cell according to an embodiment of the present application. Figure 2 for Figure 1 The exploded diagram of the single battery shown is shown in Figure 1. Figure 1 and Figure 2 The single battery cell according to the first embodiment of the present application includes a bare cell 3, a shell, and two pole units 5. The shell includes a box body 2 and a cover 1. The box body 2 includes a bottom wall 21 and side walls 22. The bottom wall 21 and the side walls 22 together form a cavity with an opening 23. Tabs 31 extend from both ends of the bare cell 3 along the length direction. The bare cell 3 is accommodated in the cavity. The cover 1 can cover the opening 23 and be sealed with the box body 2. Mounting portions 12 are respectively provided at positions corresponding to the two tabs 31 on the shell. The pole unit 5 is connected to the mounting portion 12 and is electrically connected to the tabs 31 to facilitate output connection of the bare cell 3. Among them, the bottom wall 21 of the shell is located on one side of the thickness direction of the bare cell 3, and the opening 23 is located on the opposite side of the bottom wall 21. The opening 23 can allow the bare cell 3 to pass through. Therefore, the bare cell 3 can be loaded into the cavity along the thickness direction from the opening 23 of the box body 2, and then the cover plate 1 is sealed. During assembly, the bare cell 3 has a small entry stroke into the shell, which reduces the difficulty of assembly and solves the problem of the bare cell 3 being easily scratched during the entry process, thereby effectively improving the assembly efficiency and ensuring the stability and safety of the battery. Moreover, compared with the long cylindrical shell in conventional technology, in the single battery of the embodiment of the present application, the shell body 2 and the cover plate 1 are easier to process. Therefore, the wall thickness of the box body 2 and the thickness of the cover plate 1 can be further reduced, which helps to improve the mass energy density and volume energy density.

[0058] In addition, in conventional single-cell batteries with long battery structures, the welding operation space between the terminals on both sides and the bare battery cell 3 tabs 31 is small, the connection part occupies more space, and the insulation treatment of the exposed metal part is more difficult. In addition, the tabs 31 cannot be orderly bundled. Under the later vibration and impact conditions, the risk of tabs 31 being inserted internally is prone to occur, affecting the performance and safety of the battery cell. When assembling the single-cell battery of the embodiment of the present application, the tabs 31 can be electrically connected to the adapter 51 first, and then installed into the box body 2 through the opening 23 of the box body 2. The operation is convenient, and the transfer operation is completed outside the box body 2. Therefore, the tabs 31 can be orderly bundled and convenient for the tabs 31 to be completely insulated. The insulation is reliable and can effectively prevent the tabs 31 from being inserted internally, thereby ensuring performance and safety.

[0059] Based on the above implementation modes, some specific examples are provided below:

[0060] Figure 1 This is a schematic structural diagram of a single cell according to an embodiment of the present application. Figure 2 for Figure 1 The exploded diagram of the single battery shown is Figure 3 for Figure 1 The AA section view in the figure, Figure 4 for Figure 3 The enlarged diagram of the B part in the figure is shown in the figure below. Figures 1 to 4 In this embodiment, the mounting portion 12 on the housing for connecting the pole unit 5 is provided on the cover plate 1. The two mounting portions 12 are located on the cover plate 1 at positions corresponding to the two tabs 31. The pole unit 5 is connected to the mounting portion 12 on the cover plate 1 to facilitate connection with the tabs 31. A groove 24 is provided at the junction of the bottom wall 21 and the side wall 22 of the box body 2. The groove 24 corresponds to the position of the pole unit 5 and is recessed toward the cavity, thereby forming a space-avoiding structure. When multiple single cells are stacked in the thickness direction, the groove 24 can avoid the pole unit 5 of adjacent single cells, eliminating the need to reserve additional space for the pole unit 5 installation and improving space utilization.

[0061] refer to Figure 3 and Figure 4 In some embodiments of the single battery, the above-mentioned groove 24 has a second groove wall 242 on one side along the length direction of the bare battery cell 3. The second groove wall 242 can be used to support the bare battery cell 3, thereby limiting the two ends of the bare battery cell 3 in the length direction, avoiding the bare battery cell 3 from shaking along the length direction, thereby ensuring the stability of the connection of the tab 31.

[0062] refer to Figures 2 to 4In some embodiments of the single battery, the pole unit 5 includes an adapter 51, a connector 54 and an external conductive terminal 53. The adapter 51 is located in the cavity and is electrically connected to the pole ear 31. The external conductive terminal 53 is located outside the cavity and is conductively connected to the adapter 51. The adapter 51 and the external conductive terminal 53 are connected to the mounting portion 12 through the connector 54. The connection structure is simple and easy to implement. The top cover in the conventional long battery structure is eliminated, which simplifies the assembly and can reduce the cost to a certain extent. An external insulating member 52 is also provided between the external conductive terminal 53 and the side of the cover plate 1 facing away from the bare battery cell 3 to achieve insulation between the cover plate 1 and the external conductive terminal 53. Among them, the mounting portion 12 includes a plurality of mounting holes, and through holes are respectively provided at the positions corresponding to the mounting holes on the adapter 51, the external conductive terminal 53 and the external insulating member 52. Correspondingly, the connector 54 includes a plurality of rivets, which can be 1, 2 or more. Figures 2 to 4 The two rivets are used to ensure the stability of the connection. The rivets pass through the mounting holes and the above-mentioned through holes to rivet the adapter 51, the external conductive terminal 53 and the cover 1 together, thereby achieving a fixed connection and conductive connection between the adapter 51 and the external conductive terminal 53.

[0063] refer to Figures 2 to 4 In some embodiments of the single battery, the adapter 51 includes a first section 511 and a second section 512. The first section 511 is used to connect to the connector 54, and the tab 31 is electrically connected to the second section 512. The first section 511 is parallel to the cover plate 1, facilitating connection thereto. The second section 512 is perpendicular to the extension direction of the tab 31. Therefore, after being bent and folded, the tab 31 can be positioned between the bare cell 3 body and the second section 512, facilitating the tightening, fixation, and welding of the tab 31.

[0064] Figure 5 for Figure 1 The schematic diagram of the bare cell 3, the cover plate 1 and the pole unit 5 in the single battery before assembly is shown. Figure 6 for Figure 5 The bare cell 3, cover plate 1 and pole unit 5 are assembled as shown in FIG. Figure 5 and Figure 6 When assembling the single battery of the above embodiment, the tab 31 can be electrically connected to the adapter 51 first, and then sealed and fixed to the cover plate 1 and the external conductive terminal 53 through the connector 54, and then the assembly (such as Figure 6 As shown in the figure, the battery is loaded into the cavity of the box body 2, which is easy to operate, has no risk of scratching the bare battery cell 3, and has high assembly efficiency. The transfer operation is completed outside the box body 2, with a large operating space and low difficulty, which can effectively improve the assembly efficiency. The tabs 31 can be orderly gathered and completely insulated, and the insulation is reliable.

[0065] refer to Figures 2 to 4In some embodiments of the single battery cells, a first insulating structure is provided between the casing 2 and the bare cell 3, and a second insulating structure is provided between the cover plate 1 and the bare cell 3. The first and second insulating structures are interconnected and serve to insulate the bare cell 3. An external insulating member 52 is also provided between the external conductive terminal 53 and the outer surface of the casing. Compared to a structure with a long cylindrical casing, the provision of a first insulating structure between the casing 2 and the bare cell 3, and a second insulating structure between the cover plate 1 and the bare cell 3, is relatively easy to manufacture, and a variety of insulation methods can be selected based on actual needs.

[0066] refer to Figures 2 to 4 In some embodiments of the single battery, the first insulating structure may include an insulating box 4, which is sleeved in the box body 2 and located between the bare cell 3 and the box body 2, and covers the outside of the bare cell 3. The insulating box 4 has a connection port 43 on the side facing the cover plate 1, and the second insulating structure is connected to the insulating box 4 at the connection port 43 to achieve insulation of the bare cell 3. Therefore, the insulating box 4 can be manufactured separately for easy processing. Alternatively, the first insulating structure may include a first insulating layer, which is connected to the second insulating structure to achieve insulation of the bare cell 3. The first insulating layer is made of an insulating material and attached to the inner surface of the box body 2, which can simplify assembly and help improve assembly efficiency.

[0067] refer to Figures 2 to 4 In the single cell battery of the above embodiment, the second insulating structure may include an insulating plate 6, which is located between the cover plate 1 and the bare cell 3. The insulating plate 6 is connected to the first insulating structure (insulating box 4 or first insulating layer) to insulate the bare cell 3. Therefore, the insulating plate 6 can be manufactured separately, facilitating processing. Alternatively, the second insulating structure may include a second insulating layer 11, which is made of an insulating material and attached to the side of the cover plate 1 facing the cavity. The second insulating layer 11 is connected to the first insulating structure (insulating box 4 or first insulating layer) to insulate the bare cell 3. Attaching the second insulating layer 11 to the cover plate 1 can simplify assembly and help improve assembly efficiency.

[0068] Figures 2 to 4In the illustrated embodiment, the first insulating structure includes an insulating box 4, and the second insulating structure includes a second insulating layer 11. The insulating box 4 is sleeved in the box body 2 and is located between the bare cell 3 and the box body 2. The insulating box 4 has a connection port 43 on the side facing the cover plate 1. The second insulating layer 11 is made of an insulating material and attached to the side of the cover plate 1 facing the cavity. The second insulating layer 11 is connected to the insulating box 4 at the connection port 43. The insulating box 4 and the second insulating layer 11 can be made of the same or similar insulating material, and the insulating box 4 and the second insulating layer 11 can be connected to each other by hot melt welding. The second insulating layer 11 can adopt a uniform thickness structure or a non-uniform thickness structure. For example, the thickness of the second insulating layer 11 can be appropriately increased at the position used to connect the pole unit 5 to ensure the effectiveness of the insulation after connection. The insulating box 4 is box-shaped and can be made into a structure that imitates the box body 2. The insulating box 4 is mounted inside the box body 2 and can adapt to the inner wall of the box body 2. Corresponding to the position where the groove 24 is provided on the box body 2, the insulating box 4 is also correspondingly provided with a concave first recessed portion 41. Therefore, after the insulating box 4 is installed in the box body 2, the groove 24 of the box body 2 can support and limit the first recessed portion 41. The bare battery cell 3 is installed inside the insulating box 4, and the first recessed portion 41 of the insulating box 4 can support and limit the two ends of the bare battery cell 3 along the length direction.

[0069] In addition, on the insulating box 4, second recessed portions 42 are provided on both sides of the first recessed portion 41. The second recessed portions 42 are recessed inward from the side of the insulating box 4. Therefore, after the insulating box 4 is put on the outside of the bare battery cell 3, welding areas 44 are formed between the second recessed portions 42 at both ends and the cover plate 1. Through these welding areas, the insulating box 4 can be conveniently welded to the second insulating layer 11 of the top plate.

[0070] Figure 7 This is a schematic diagram before the insulation box 4 and the cover plate 1 are assembled. Figure 8 for Figure 7 Schematic diagram of the assembled insulating box 4 and cover plate 1, Figure 9 This is a schematic diagram of the box body 2 and the cover plate 1 before assembly, refer to Figures 7 to 9 During assembly, first assemble the bare cell 3, the cover plate 1 and the pole unit 5 into a whole and assemble it with the insulating box 4, then insert the insulating box 4 from one side of the bare cell 3 along the thickness direction of the bare cell 3, so that the insulating box 4 is wrapped around the outside of the bare cell 3, and the connection port 43 of the insulating box 4 is in contact with the second insulating layer 11 on the inner surface of the cover plate 1, then perform hot melt welding on the joint between the connection port 43 and the second insulating layer 11, and hot melt welding can be performed on the above-mentioned welding area 44, then put the box body 2 on the outside of the insulating box 4 along the thickness direction of the bare cell 3, and weld the cover plate 1 and the box body 2 to achieve sealing and fixation of the cover plate 1 and the box body 2.

[0071] The single cell battery of the embodiment of the present application is based on the above-mentioned structural arrangement, which can reduce the difficulty of assembly and eliminate the top cover in the conventional structure, thereby simplifying the structure and assembly; the box body 2 and the cover plate 1 are easy to process, and the wall thickness of the box body 2 and the cover plate 1 can be further reduced, which can effectively improve the mass and volume energy density.

[0072] Figure 10 This is a schematic diagram of the arrangement of multiple single cells in a battery pack according to an embodiment of the present application, with reference to Figure 1 and Figure 10 The second embodiment of the present application provides a battery pack, comprising a plurality of single cells according to the first embodiment. The plurality of single cells are arranged in sequence along the thickness direction, which can improve the integration efficiency inside the battery pack, improve the volume space utilization rate, and realize a battery pack with high energy density and high assembly efficiency.

[0073] Figure 11 This is a schematic structural diagram of a single cell according to another embodiment of the present application. Figure 12 for Figure 11 The schematic structural diagram of the box body 2 in the embodiment shown, Figure 13 for Figure 11 A schematic diagram from another perspective, Figure 14 for Figure 11 The exploded schematic diagram of the single cell shown in FIG. 1 shows that in the single cell of this embodiment, the position of the mounting portion 12 for mounting the pole unit 5 is different from that in the above-mentioned embodiment. Accordingly, the structures of the box body 2 and the cover plate 1 are also different. A groove 24 is provided on the box body 2 of the single cell of this embodiment at positions corresponding to the two tabs 31. The groove 24 is recessed toward the interior of the cavity and has a first groove wall 241 facing the cover plate 1. The first groove wall 241 is provided with the mounting portion 12 for mounting the pole unit 5. The pole unit 5 is connected to the box body 2 at the mounting portion 12. In this embodiment, the inwardly recessed groove 24 forms a space for accommodating the pole unit 5. When multiple single cells are stacked in the thickness direction, the groove 24 can accommodate the pole unit 5, preventing the pole unit 5 from interfering with the casing of adjacent single cells. Therefore, there is no need to reserve additional space for the pole unit 5 in the thickness direction of the bare cell 3, thereby improving space utilization.

[0074] Figure 15 for Figure 13 The CC section view in the figure, Figure 16 for Figure 15 The enlarged schematic diagram of the D part in the figure is shown in the figure below. Figure 15 and Figure 16In some embodiments of the present application, the groove 24 on the box body 2 has a second groove wall 242 on one side along the length direction of the bare battery cell 3. The second groove wall 242 can be used to support the bare battery cell 3, thereby limiting the two ends of the bare battery cell 3 in the length direction to prevent the bare battery cell 3 from shaking along the length direction, thereby ensuring the stability of the connection of the tab 31.

[0075] refer to Figures 13 to 16 In some embodiments of the single battery, the pole unit 5 includes an adapter 51, a connector 54 and an external conductive terminal 53. The adapter 51 is located in the cavity and is electrically connected to the tab 31. The external conductive terminal 53 is located outside the cavity and is conductively connected to the adapter 51. The adapter 51 and the external conductive terminal 53 are connected to the mounting portion 12 of the first slot wall 241 through the connector 54. The connection structure is simple and easy to implement. The top cover in the conventional long battery structure is eliminated, which simplifies the assembly and can reduce the cost to a certain extent. An external insulating member 52 is also provided between the external conductive terminal 53 and the side of the first slot wall 241 facing away from the adapter 51 to achieve insulation between the box body 2 and the external conductive terminal 53. Among them, the mounting portion 12 includes a plurality of mounting holes, and through holes are respectively provided at the positions corresponding to the mounting holes on the adapter 51, the external conductive terminal 53 and the external insulating member 52. Correspondingly, the connector 54 includes a plurality of rivets, which can be 1, 2 or more. Figures 13 to 16 Two rivets are used, passing through the mounting holes and the aforementioned through-holes to rivet the adapter 51, the external conductive terminal 53, and the cover 1 together, achieving a fixed and conductive connection between the adapter 51 and the external conductive terminal 53. The first slot wall 241 can be arranged parallel to the cover 1, facilitating installation of the pole unit 5.

[0076] refer to Figures 13 to 16 In some embodiments of the single battery cells, the adapter 51 includes a first section 511 and a second section 512. The first section 511 is used to connect to the connector 54, and the tab 31 is electrically connected to the second section 512. The first section 511 is parallel to the first slot wall 241, facilitating connection thereto. The second section 512 is perpendicular to the extension direction of the tab 31. Therefore, after being bent and folded, the tab 31 can be positioned between the bare cell 3 body and the second section 512, facilitating the tightening, fixation, and welding of the tab 31.

[0077] In some embodiments of the single battery cells, a first insulating structure is provided between the casing 2 and the bare cells 3, and a second insulating structure is provided between the cover plate 1 and the bare cells 3. The first and second insulating structures are interconnected and serve to insulate the bare cells 3. An external insulating member 52 is also provided between the external conductive terminals 53 and the outer surface of the casing. Compared to a structure with an elongated cylindrical casing, the provision of a first insulating structure between the casing 2 and the bare cells 3, and a second insulating structure between the cover plate 1 and the bare cells 3, is relatively easy to manufacture, and a variety of insulation methods can be selected based on actual needs.

[0078] Figures 13 to 16 In some embodiments of the single battery, the first insulating structure may include an insulating box 4, which is sleeved in the box body 2 and located between the bare cell 3 and the box body 2, and covers the outside of the bare cell 3. The insulating box 4 has a connection port 43 on the side facing the cover plate 1, and the second insulating structure is connected to the insulating box 4 at the connection port 43 to achieve insulation of the bare cell 3. Therefore, the insulating box 4 can be manufactured separately for easy processing. Alternatively, the first insulating structure may include a first insulating layer, which is connected to the second insulating structure to achieve insulation of the bare cell 3. The first insulating layer is made of an insulating material and attached to the inner surface of the box body 2, which can simplify assembly and help improve assembly efficiency.

[0079] Figures 13 to 16 In the single cell battery of the above embodiment, the second insulating structure may include an insulating plate 6, which is located between the cover plate 1 and the bare cell 3. The insulating plate 6 is connected to the first insulating structure (insulating box 4 or first insulating layer) to insulate the bare cell 3. Therefore, the insulating plate 6 can be manufactured separately, facilitating processing. Alternatively, the second insulating structure may include a second insulating layer 11, which is made of an insulating material and attached to the side of the cover plate 1 facing the cavity. The second insulating layer 11 is connected to the first insulating structure (insulating box 4 or first insulating layer) to insulate the bare cell 3. Attaching the second insulating layer 11 to the cover plate 1 can simplify assembly and help improve assembly efficiency.

[0080] Figures 13 to 16 In the illustrated embodiment, the first insulating structure includes an insulating box 4, and the second insulating structure includes an insulating plate 6. The insulating box 4 is sleeved in the box body 2 and is located between the bare battery cell 3 and the box body 2. The insulating box 4 has a connection port 43 on the side facing the cover plate 1. The insulating plate 6 is located between the cover plate 1 and the bare battery cell 3. The insulating plate 6 is connected to the insulating box 4 at the connection port 43. The insulating box 4 and the insulating plate 6 can be made of the same or similar insulating material, and the insulating plates 6 can be connected to each other by hot melt welding. Figure 17 for Figure 11 The schematic diagram of the box body 2 and the insulating box 4 in the single battery before assembly is shown. Figures 13 to 17The insulating box 4 is box-shaped and can be made into a conformal structure with the box body 2. The insulating box 4 is sleeved inside the box body 2 and can adapt to the inner wall of the box body 2. Corresponding to the position where the groove 24 is provided on the box body 2, the insulating box 4 is also correspondingly provided with a concave first recessed portion 41. The first recessed portion 41 has a first wall 411 parallel to the first groove wall 241 of the groove 24 of the box body 2, and a through hole is provided on the first wall 411 at a position corresponding to the mounting hole for the installation of the connector 54. The first wall 411 can insulate the adapter 51 and the box body 2. In addition, the first recessed portion 41 has a second wall 412 corresponding to the direction of the bare battery cell 3. After the insulating box 4 is installed in the box body 2, the groove 24 of the box body 2 can be adapted to the first recessed portion 41, and the second wall 412 is abutted against the second groove wall 242 of the groove 24. The bare battery cell 3 is installed inside the insulating box 4, and the first wall 411 of the first recessed portion 41 of the insulating box 4 can abut and limit the two ends of the bare battery cell 3 along the length direction.

[0081] Figure 18 for Figure 11 The schematic diagram of the bare cell 3 and the adapter 51 in the single battery before assembly is shown. Figure 19 for Figure 11 A schematic diagram of the structure of the bare battery cell 3, the box body 2 and the pole unit 5 before assembly, Figure 20 for Figure 19 A schematic diagram of the structure after the bare battery cell 3, the box body 2 and the pole unit 5 are assembled, Figure 21 This is a schematic diagram of the box body 2, cover plate 1 and insulation plate 6 before assembly, refer to Figures 17 to 21 When assembling the single battery of the above embodiment, the box body 2 and the insulating box 4 can be connected to prepare for assembly. Figure 17 And first the bare cell 3 tab 31 and the adapter 51 are electrically connected and fixed, such as Figure 18 Then connect the bare core 3 with the adapter 51 from the side of the box body 2 along the thickness direction into the box body 2 and the insulating box 4 sleeve into the assembly, such as Figure 19 , and then the external conductive terminal 53, the adapter 51, the box body 2 and the insulating box 4 are sealed and fixedly installed on the mounting portion 12 of the box body 2 through the connecting member 54; Figure 20 and Figure 21 After the bare cell 3, box body 2, insulating box 4, and pole unit 5 are assembled, the insulating box 4 is wrapped around the bare cell 3 and adapter 51. The insulating plate 6 is sealed to the connection port 43 of the insulating box 4 and welded. The cover plate 1 is sealed to the opening 23 of the box body 2 and welded in place. This completes the assembly of the single battery cell, which is convenient, eliminates the risk of scratching the bare cell 3, and improves assembly efficiency. The connection operation between the tab 31 and the adapter 51 can be completed outside the box body 2, which provides ample space and reduces difficulty, effectively improving assembly efficiency. The tab 31 can also be neatly bundled and completely insulated, ensuring reliable insulation.

[0082] In the above embodiment, the box body 2 can adopt a uniform wall thickness structure, and regular or irregular reinforcement ribs can be added at local locations to meet strength and connection requirements. The box body 2 can also adopt a unequal wall thickness structure. For example, the wall thickness can be appropriately increased or regular or irregular reinforcement ribs can be added at local locations to meet strength and connection requirements. The wall thickness can also be appropriately reduced at local locations to reduce the overall thickness and weight of the single battery.

[0083] refer to Figure 11 and Figure 22 The single cells of the present invention, based on the aforementioned structural arrangement, can reduce assembly difficulty and eliminate the top cover found in conventional structures, simplifying both structure and assembly. The box body 2 and cover plate 1 are simple to manufacture, allowing for further reductions in the wall thickness of the box body 2 and the cover plate 1, effectively improving both mass and volumetric energy density. When used in a battery pack, multiple single cells are arranged sequentially along the thickness direction, improving internal integration efficiency and volumetric space utilization, resulting in a battery pack with high energy density and high assembly efficiency.

[0084] The second embodiment of the present application provides a battery pack (not shown), comprising a housing and a plurality of single cells according to any one of the first embodiments, the single cells being housed in the housing. The multiple single cells can be assembled into a module and then assembled in the housing in a modular manner, or the multiple single cells can be directly assembled in the housing. The multiple single cells are arranged in sequence along the thickness direction (see Figure 10 and Figure 22 ), which can improve the integration efficiency inside the battery pack, increase the volume space utilization, and achieve a battery pack with high energy density and high assembly efficiency.

[0085] The single cells and battery packs of the embodiments of the present application can be used in power battery systems, for example, as the main power source of electric vehicles. The structure of the single cell has a significant impact on the energy density, economy, and safety of the power battery. As mentioned above, the single cell of the embodiment of the present application adopts a long double-pass structure with poles at both ends to form a double-pass battery with high capacity density, and optimizes the shell and pole unit connection structure to effectively improve assembly efficiency, ensure battery stability and safety, and improve the quality of the single cell energy density and volume energy density. Therefore, the battery pack composed of the single cell can effectively improve the battery energy density, while meeting functional and safety requirements while also reducing costs.

[0086] The embodiments of the present application have been described in detail above with reference to the accompanying drawings. However, the present application is not limited to the above embodiments. Various modifications can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of the present application. In addition, the embodiments of the present application and the features of the embodiments can be combined with each other unless there is a conflict.

Claims

1. A single cell battery, characterized in that: include: A bare battery cell, wherein tabs extend from both ends of the bare battery cell along the length direction; The shell comprises a box body and a cover plate, the box body comprises a bottom wall and side walls, the bottom wall and the side walls together form a cavity with an opening, the bare cell is accommodated in the cavity, the bottom wall is located on one side in the thickness direction of the bare cell, the opening is located on the opposite side of the bottom wall, the opening can allow the bare cell to pass through, the cover plate can cover the opening and be sealed with the box body; the box body is respectively provided with grooves at positions corresponding to the two tabs, the grooves are recessed toward the cavity, the grooves have a first groove wall facing the cover plate, the positions of the first groove wall corresponding to the two tabs are respectively provided with mounting portions, and the groove has a second groove wall on the side facing the length direction of the bare cell; Two pole units, each comprising an adapter, a connector, an external conductive terminal, and an external insulating member, the adapter being located in the cavity, the adapter comprising a first section and a second section, the first section being parallel to the first slot wall, the second section being perpendicular to the extension direction of the tab, the tab being electrically connected to the second section after being bent, the external conductive terminal being located outside the cavity and conductively connected to the adapter, the first section and the external conductive terminal being connected to the mounting portion via the connector; the external insulating member being located between the external conductive terminal and the outer surface of the housing; An insulating box and a second insulating structure, a second insulating structure is provided between the cover plate and the bare cell, the insulating box and the second insulating structure are used to insulate the bare cell, the insulating box is sleeved in the box body and is located between the bare cell and the box body, the insulating box is covered on the outside of the bare cell and the adapter, the insulating box has a connection port on the side facing the cover plate, and the second insulating structure is connected to the insulating box at the connection port; the insulating box is provided with a first concave recessed portion corresponding to the position of the groove, and the first recessed portion has a first wall parallel to the first groove wall The body, the mounting portion includes a plurality of mounting holes, and through holes are respectively provided on the adapter, the external conductive terminal, the external insulating member and the first wall body at positions corresponding to the mounting holes. The connecting member includes a plurality of rivets, and the rivets pass through the mounting holes and the through holes to rivet the adapter, the external conductive terminal, the external insulating member and the first wall body. The first wall body is located between the first section and the first groove wall and is used to insulate the adapter and the box body; the first recessed portion has a second wall body corresponding to the direction of the bare battery cell, and the second wall body is in contact with the second groove wall.

2. The single cell according to claim 1, characterized in that: The second insulating structure includes an insulating plate, which is located between the cover plate and the bare cell, and the insulating plate is connected to the insulating box; or, the second insulating structure includes a second insulating layer, which is attached to the side of the cover plate facing the cavity, and the second insulating layer is connected to the insulating box.

3. A battery pack, characterized in that: The invention comprises a case and a plurality of single cells according to any one of claims 1 to 2, wherein the single cells are accommodated in the case.

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