Lower plastic, cover plate assembly, energy storage apparatus, and electric device

Abstract

A lower plastic (100), comprising a first surface (110) having a first recess (111) and a second surface (120) having a second recess (121). The second surface (120) and the first surface (110) are disposed facing away from one another along the thickness direction of the lower plastic (100) and communicate with one another along the length direction of the lower plastic (100), and the bottom of the first recess (111) extends to the second surface (120).

Description

Lower plastic, cover assembly, energy storage device and power device

[0001] Priority information

[0002] This application claims priority and benefits of patent application No. 2023111640176 filed with the State Intellectual Property Office of China on September 11, 2023, and the entire text of which is incorporated herein by reference. Technical Field

[0003] The present application belongs to the field of batteries, and specifically relates to lower plastic, cover assembly, energy storage device and power consumption device. Background Art

[0004] As energy storage batteries develop toward larger capacities, the size of the plastic under the battery cover is inevitably increasing. Currently, large-size cover designs typically utilize holes in the lower plastic to facilitate exhaust in the event of overheating. However, these holes in the lower plastic are designed to provide longitudinal ventilation, creating direct contact with the internally wound battery cells. This poses a risk of blockage and can easily lead to poor exhaust flow.

[0005] Summary of the Invention

[0006] The present application aims to solve, at least to a certain extent, one of the technical problems in the related art. To this end, one purpose of the present application is to provide a lower plastic, a cover assembly, an energy storage device, and an electrical device. The lower plastic adopts a structural design in which a first groove and a second groove are interconnected along its length and arranged in opposite directions along its thickness. This can not only reduce the risk of blockage in the longitudinal exhaust channel, but also add a transverse exhaust channel on the basis of the longitudinal exhaust channel, which is conducive to the gas converging below the explosion-proof valve.

[0007] The first aspect of the present application provides a lower plastic. According to an embodiment of the present application, the lower plastic includes:

[0008] a first side, the first side comprising at least one first groove;

[0009] The second surface is arranged opposite to the first surface along the thickness direction of the lower plastic, and the second surface includes at least one second groove, each second groove is connected to at least one first groove along the length direction of the lower plastic, and the bottom of the first groove extends to the second surface.

[0010] The lower plastic of the above embodiment of the present application has the following advantages: by providing grooves on both sides of the lower plastic that are arranged opposite to each other along its thickness direction, when the lower plastic is used in the cover assembly to encapsulate the battery cell shell, there is a gap between the groove portion opening toward the bare battery and the bare battery cell. On the one hand, the contact area between the lower plastic and the bare battery cell can be reduced, reducing the risk of partial exhaust channel blockage during transportation or use of the battery cell. On the other hand, the second groove and the first groove are connected along the length direction of the lower plastic, which can realize gas circulation between the first groove and the second groove, and can guide the gas on the side of the lower plastic close to the bare battery cell to the bottom of the cover assembly. The lower plastic is away from the side of the bare battery cell, and the gas can also flow along the length direction of the lower plastic, that is, a transverse exhaust channel is added on the basis of the longitudinal exhaust channel, which is not only conducive to the gas gathering below the explosion-proof valve, meeting the exhaust needs of the battery cell in the case of overheating and reducing the risk of poor exhaust, but also allows the bottom of the first groove to extend to the second side. During the battery cell packaging process, the second side can also be made to face the side of the bare battery cell, so that there is no need to reserve a gap between the lower plastic and the bare battery cell to meet the exhaust needs. The lower plastic can be directly pressed on the bare battery cell to prevent the battery cell from shaking and improve the internal stability of the battery cell.

[0011] The second aspect of the present application proposes a cover assembly. According to an embodiment of the present application, the cover assembly includes the above-mentioned lower plastic. Using the above-mentioned lower plastic in the cover assembly not only facilitates the convergence of gas produced by the battery cells to the bottom of the explosion-proof valve, meeting the exhaust requirements of the battery cells in the event of overheating and reducing the risk of poor exhaust, but also allows the lower plastic to directly press the bare battery cells when packaging the battery cells, thereby preventing the battery cells from shaking and improving the internal stability of the battery cells.

[0012] The third aspect of the present application provides an energy storage device. According to an embodiment of the present application, the energy storage device includes:

[0013] a housing having an opening;

[0014] A cover assembly, the cover assembly closes the opening, the cover assembly is the above-mentioned cover assembly, or includes the above-mentioned lower plastic;

[0015] A bare battery cell is housed in the shell.

[0016] The features and effects described above for the lower plastic and cover components also apply to this energy storage device and will not be repeated here. In general, this energy storage device can not only better meet the exhaust requirements in the event of overheating of the battery cell, but also achieve better internal stability of the battery cell.

[0017] A fourth aspect of the present application provides an electrical device. According to an embodiment of the present application, the electrical device includes the aforementioned energy storage device. The features and effects described for the aforementioned energy storage device also apply to the electrical device and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic structural diagram of a lower plastic according to an embodiment of the present application.

[0019] FIG. 2 is an enlarged view of a first surface of one end of the lower plastic shown in FIG. 1 along its length direction.

[0020] FIG. 3 is an enlarged view of a second surface of one end of the lower plastic shown in FIG. 1 along its length direction.

[0021] FIG4 is a cross-sectional view and a partially enlarged view of the lower plastic parallel to its thickness direction according to one embodiment of the present application.

[0022] FIG5 is a schematic structural diagram of a lower plastic including a first sub-lower plastic and a second sub-lower plastic according to an embodiment of the present application.

[0023] FIG6 is a schematic structural diagram of an optical cover according to an embodiment of the present application.

[0024] FIG. 7 is a cross-sectional view and a partially enlarged view of a light cover plate parallel to its thickness direction according to one embodiment of the present application.

[0025] FIG8 is an exploded view of a cover plate assembly according to one embodiment of the present application.

[0026] FIG9 is a schematic structural diagram of an energy storage device according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] The following describes in detail embodiments of the present application, examples of which 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 intended to be used to explain the present application, and should not be construed as limiting the present application.

[0028] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "thickness", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", "third", and "fourth" may explicitly or implicitly include at least one such feature. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0029] The first aspect of the present application provides a lower plastic 100. According to an embodiment of the present application, as understood with reference to Figures 1-3 , the lower plastic 100 includes: a first surface 110 and a second surface 120. The first surface 110 includes at least one first groove 111. The second surface 120 is disposed opposite the first surface 110 along the thickness direction of the lower plastic 100. The second surface 120 includes at least one second groove 121. Each second groove 121 is connected to at least one first groove 111 along the length direction of the lower plastic 100, and the bottom of the first groove 111 extends to the second surface 120. It is understood that in actual use, the first surface 110 can face the light cover 200 (shown in Figures 6 or 8 ) of the battery cover assembly, and the second surface 120 can face the bare battery cells. It is understood that the light cover 200 is the main component of the battery cover assembly, and related components such as the terminal 700 (shown in Figures 6 or 8 ) and the explosion-proof valve 400 (shown in Figures 6 or 8 ) can be fixed to the light cover 200.

[0030] The lower plastic 100 has the following advantages: by providing grooves on two opposite surfaces of the lower plastic 100 along its thickness direction, when the lower plastic 100 is used in the cover assembly to encapsulate the battery cell shell, there is a gap between the groove portion opening toward the bare battery and the bare battery cell, which can reduce the contact area between the lower plastic 100 and the bare battery cell, and reduce the risk of partial exhaust channel blockage during transportation or use of the battery cell; on the other hand, the first groove 111 and the second groove 121 are connected along the length direction of the lower plastic 100, which can realize the gas circulation of the first groove 111 and the second groove 121 to form a transverse exhaust channel, which can not only guide the gas located on the side of the lower plastic 100 close to the bare battery cell to the side of the lower plastic 100 away from the bare battery cell, but also make the gas circulate along the length direction of the lower plastic 100, that is, a transverse exhaust channel is added on the basis of the longitudinal exhaust channel. To the exhaust channel, which is not only conducive to the gas to converge to the bottom of the explosion-proof valve 400 (specifically, the gas generated by the battery cell will be conducted as a whole through the transverse exhaust channel, and will not be stored in the groove of the lower plastic 100 in sections, and the weak part of the entire battery is located at the explosion-proof valve. The transverse channel can be used to collect the gas generated by the battery to a unified weak part for explosion, such as gathering below the explosion-proof valve 400 and then exploding), meeting the exhaust needs of the battery cell in the event of overheating and reducing the risk of poor exhaust. In addition, the bottom of the first groove 111 is extended to the second surface 120. During the battery cell packaging process, the second surface 120 can also be made to face the side of the bare battery cell, so that there is no need to reserve a gap between the lower plastic 100 and the bare battery cell to meet the exhaust needs. The lower plastic 100 can be directly pressed on the bare battery cell to prevent the battery cell from shaking and improve the internal stability of the battery cell. It can be understood that the longitudinal exhaust channel mentioned in this application refers to the exhaust channel along the thickness direction of the lower plastic, and the transverse exhaust channel refers to the exhaust channel along the length direction of the lower plastic 100.

[0031] The lower plastic of the above embodiment of the present application is described in detail below with reference to Figures 1 to 9.

[0032] In some embodiments of the present application, in combination with Figures 1 to 4, one of the first surface 110 and the second surface 120 of the lower plastic 100 faces the bare battery cell, and the other faces the light cover 200 of the battery cover assembly. Taking the first surface 110 facing the light cover 200 and the second surface 120 facing the bare battery cell as an example, the lower plastic 100 can be directly pressed on the bare battery cell. At this time, a gap is formed between the first surface 110 corresponding to the second groove 121 and the bare battery cell. The gap space can accommodate the gas generated by the battery cell and introduce the gas into the first surface 110 of the lower plastic 100 through the connection between the second groove 121 and the first groove 111. In addition, when the multiple second grooves 121 and the first groove 111 are continuously and alternately arranged along the length direction of the lower plastic 100, a transverse gas channel extending along the length direction of the lower plastic 100 can also be formed, so that the gas can pass in sequence between the multiple first grooves 111 and the second grooves 121 continuously and alternately arranged along the length direction of the lower plastic 100 until it reaches the area below the explosion-proof valve 400. Preferably, with reference to Figure 1, an explosion-proof valve exhaust area 130 can be provided on the lower plastic 100. In the length direction of the lower plastic 100, at least one end of the explosion-proof valve exhaust area 130 is connected to the first groove 111 and / or the second groove 121. This arrangement can make the horizontal exhaust channel directly connected to the explosion-proof valve exhaust area 130, which is more conducive to the gas generated by the battery cell to converge to the explosion-proof valve exhaust area 130, thereby reducing the risk of poor exhaust of the battery cell.

[0033] In some embodiments of the present application, referring to Figures 1 to 4 , the lower plastic 100 may include: a plurality of first grooves 111 and second grooves 121 continuously and alternately arranged along the length of the lower plastic 100. The total number of the continuously and alternately arranged first grooves 111 and second grooves 121 is no less than 2, and preferably no less than 3. Taking the second surface 120 facing the bare cell as an example, gas is discharged from the bare cell. If the contact surface between the second surface 120 and the bare cell is too large, it is not conducive to cell exhaust. Arranging the plurality of first grooves 111 and second grooves 121 continuously and alternately along the length of the lower plastic 100 is more conducive to collecting gas generated by the cell. In addition, increasing the total number of first grooves 111 and second grooves 121 continuously and alternately arranged along the length of the lower plastic 100 helps extend the length of the transverse exhaust channel and increase the exhaust space between the lower plastic 100 and the bare cell. This not only improves the reliability of the transverse exhaust channel, but also promotes the convergence of gas generated in different areas of the cell to the explosion-proof valve exhaust area 130, reducing the risk of poor cell exhaust. As some specific examples, the total number of first grooves 111 and second grooves 121 arranged alternately in a row can be 3 to 6. This arrangement is beneficial for collecting the gas generated by the battery cells and for converging the gas along the transverse exhaust channel to the explosion-proof valve exhaust area 130.

[0034] It should be noted that the total number of the first grooves 111 and the second grooves 121 continuously and alternately arranged along the length direction of the lower plastic 100 can be equal to the total number of the first grooves 111 and the second grooves 121 in the entire lower plastic 100, or can be less than the total number of the first grooves 111 and the second grooves 121 in the entire lower plastic 100. For example, when the explosion-proof valve 400 is located at the end of the light cover 200, all the first grooves 111 and the second grooves 121 in the lower plastic 100 can be continuously and alternately arranged along the length of the lower plastic 100, and the explosion-proof valve exhaust area 130 can be connected to the first groove 111 or the second groove 121. For another example, referring to Figure 1, when the explosion-proof valve 400 is located in the middle of the light cover 200, multiple first grooves 111 and second grooves 121 can be continuously and alternately distributed on both sides of the explosion-proof valve exhaust area 130 along the length of the lower plastic 100, and the two ends of the explosion-proof valve exhaust area 130 can be respectively connected to the first groove 111 and / or the second groove 121. Both of the above methods can achieve communication between the transverse exhaust channel and the explosion-proof valve exhaust area 130.

[0035] In some embodiments of the present application, as understood with reference to Figures 1 or 4 , the first surface 110 may include a plurality of first grooves 111, which may be spaced apart along the length of the lower plastic 100; and / or the second surface 120 may include a plurality of second grooves 121, which may be spaced apart along the length of the lower plastic 100. Increasing the number of first grooves 111 and second grooves 121 may help extend the length of the lateral exhaust channel. For example, when the second surface 120 faces the bare battery cells, spacing the second grooves 120 may also help collect gases generated by the battery cells. This facilitates the convergence of gases generated by the battery cells toward the explosion-proof valve exhaust area 130, reducing the risk of poor exhaust flow from the battery cells.

[0036] In some embodiments of the present application, referring to FIG4 , it can be understood that the bottom of the first groove 111 extends to the second surface 120, and the bottom of the second groove 121 can extend to the first surface 110. This arrangement can, on the one hand, increase the size of the exhaust channel, thereby more conducive to collecting the gas generated by the battery cell and converging the collected gas to the bottom of the explosion-proof valve 400 through the transverse exhaust channel formed by the first groove 111 and the second groove 121, thereby reducing the risk of poor exhaust. On the other hand, the second surface 120 in the battery faces away from the light cover 200 and toward the bare battery cell. The extension of the bottom of the first groove 111 to the second surface 120 can allow the bottom of the first groove 111 to directly press on the bare battery cell, further preventing the battery cell from shaking and improving the internal stability of the battery cell.

[0037] In some embodiments of the present application, as understood with reference to FIG4 , the first surface 110 can be positioned away from the bare cell, and the extension distance of the first groove 111 can be no greater than the extension distance of the second groove 121 in the length direction of the lower plastic 100. When the first surface 110 of the lower plastic 100 is away from the bare cell, its second surface 120 is adapted to press against the bare cell. At this time, a gap is formed between the second groove 121 and the bare cell, which is primarily used to collect gas generated by the cell and direct the gas generated by the cell to the first groove 111 connected thereto. The first groove 111 is primarily used to cooperate with the second groove 121 to achieve lateral transmission of gas along the length direction of the lower plastic 100. Therefore, controlling the extension distance of the first groove 111 to no greater than the extension distance of the second groove 121 in the length direction of the lower plastic 100 is more conducive to collecting gas generated by the cell and converging the gas below the explosion-proof valve 400 through lateral exhaust, thereby reducing the risk of poor exhaust.

[0038] In some embodiments of the present application, the ratio of the extension distance of the first groove 111 to the extension distance of the second groove 121 in the length direction of the lower plastic 100 can be 0.2 to 1, for example, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1. The second surface 120 of the lower plastic 100 is suitable for pressing against the bare battery cell, and the bottom of the first groove 111 can preferably extend to the second surface 121 to further prevent the battery cell from shaking. However, if the extension distance of the second groove 111 in the length direction of the lower plastic 100 is too large or the extension distance of the first groove 111 in the length direction of the lower plastic 100 is too small, it is not conducive to improving the fixing effect of the bare battery cell. By controlling the extension distance of the first groove 111 and the second groove 121 in the length direction of the lower plastic 100 to meet the above conditions, it is beneficial to collect the gas generated by the battery cell and converge the gas generated by the battery cell to the bottom of the explosion-proof valve 400 through the horizontal exhaust channel formed by the first groove 111 and the second groove 121. It is also beneficial to further prevent the battery cell from shaking and enhance the improvement effect of the internal stability of the battery cell.

[0039] In some embodiments of the present application, in the longitudinal direction of the lower plastic 100, when extending from the end to the middle of the lower plastic 100, the first groove 111 can be preferentially provided, and then the second groove 121 can be provided, and they can be arranged alternately in this order, that is, at both ends of the lower plastic 100 in the longitudinal direction, the first groove 111 is closer to the end of the lower plastic 100. The premise for preventing the bare cell from shaking is to preferably fix the two ends of the bare cell at both ends of the battery (i.e., the two ends along the longitudinal direction of the optical cover) so that the two ends of the bare cell do not touch the battery shell (such as an aluminum shell, etc.). In the present application, the bottom of the first groove 111 can be directly pressed against the bare cell, so that at both ends of the lower plastic 100 in the longitudinal direction, the first groove 111 is closer to the end of the lower plastic 100. The bottom wall of the first groove 111 can be directly used to abut and fix the two ends of the bare cell, thereby improving the fixing effect of the bare cell.

[0040] In some embodiments of the present application, as will be understood from Figures 1-3 , the first and second grooves 111, 121 may each be independently provided with a reinforcing rib 140. The rib 140 may be provided along the length of the lower plastic 100. Providing the reinforcing rib 140 along the length of the lower plastic 100 not only improves the overall strength of the lower plastic 100, but also does not significantly negatively impact the exhaust efficiency of the lateral exhaust duct. Furthermore, the rib 140 may extend a distance of 0.5 mm to 1.5 mm in the width direction of the lower plastic 100, such as 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, or 1.5 mm. Increasing the distance of the rib 140 in the width direction of the lower plastic 100 may improve the overall strength of the lower plastic 100. However, if this distance is too large, it may reduce the volume of the lateral exhaust duct, affecting the exhaust efficiency. Controlling the size of the rib 140 to meet the above conditions helps to further balance the overall strength and exhaust efficiency of the lower plastic 100. As some specific examples, in the width direction of the lower plastic 100 , the reinforcing rib 140 may be located in the middle of the lower plastic 100 . This arrangement is beneficial to further improve the reinforcing effect of the reinforcing rib 140 .

[0041] In some embodiments of the present application, the ratio of the sum of the extension distances of the first groove 111 and the second groove 121 in the length direction of the lower plastic 100 to the length of the lower plastic 100 can be no less than 0.5. For example, the ratio can be 0.5, 0.6, 0.7, 0.8, or 0.9. If the length of the lateral exhaust channel is too short, it is not conducive to timely collection of gases generated in various areas of the battery cell and improving the exhaust effect. Ensuring that the extension distances of the first groove 111 and the second groove 121 in the length direction of the lower plastic 100 meet the above conditions is conducive to further improving the exhaust effect and reducing the risk of poor exhaust. Furthermore, the ratio of the sum of the extension distances of the first groove 111 and the second groove 121 in the length direction of the lower plastic 100 to the length of the lower plastic 100 can be 0.5 to 0.8. This configuration is conducive to further improving the exhaust effect without affecting the structural configuration of other holes on the lower plastic 100 (such as the pole mounting holes 151 / 152, the exhaust valve exhaust area 130, etc.).

[0042] In some embodiments of the present application, the sidewall thickness of the first groove 111 and the sidewall thickness of the second groove 121 can be independently 0.5 mm to 1.5 mm, such as 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, or 1.5 mm. If the thickness of the groove sidewall is too small, its strength is also low, and deformation is likely to occur during transportation and use of the battery cell, affecting the reliability of the exhaust channel. However, if the thickness of the groove sidewall is too large, the volume of the lateral exhaust channel will be reduced, which will also affect the exhaust effect. Controlling the sidewall thickness of the first groove 111 and the second groove 121 to meet the above conditions is conducive to further balancing the strength of the lower plastic 100 and the exhaust effect, reducing the risk of poor exhaust.

[0043] In some embodiments of the present application, as will be understood with reference to FIG1 , a first exhaust hole 112 may be further provided on the first groove 111. The first exhaust hole 112 may extend through the bottom of the first groove 111. In practical applications, the first surface 110 may be positioned away from the bare battery cell. When there is a gap between the bottom of the first groove 111 and the bare battery cell, or when the bare battery cell is not completely pressed against the first groove 111, the provision of the first exhaust hole 112 may facilitate the introduction of gas generated by the battery cell into the first groove 111 via the longitudinal exhaust channel, thereby improving exhaust efficiency.

[0044] In some embodiments of the present application, as understood with reference to FIG1 , an explosion-proof valve exhaust area 130 may be provided on the lower plastic 100. The explosion-proof valve exhaust area 130 is provided with a second exhaust through-hole 131 extending through the thickness of the lower plastic 100. The explosion-proof valve exhaust area 130 is connected to at least one first groove 111 and / or at least one second groove 121 along the length of the lower plastic 100. This arrangement not only increases the longitudinal exhaust channel but also enables the connection between the transverse exhaust channel and the explosion-proof valve exhaust area, further ensuring that the gas generated by the battery cells can smoothly converge into the explosion-proof valve exhaust area 130, reducing the risk of poor exhaust.

[0045] In some embodiments of the present application, multiple first grooves 111 and second grooves 121 can be independently and continuously alternately arranged on both sides of the explosion-proof valve exhaust area 130 along the length direction of the lower plastic 100. This arrangement not only connects the lateral exhaust channel with the explosion-proof valve exhaust area 130, but also helps shorten the path for gas generated by the battery cells to converge into the explosion-proof valve exhaust area 130, shortening exhaust time, further improving exhaust efficiency, and reducing the risk of poor exhaust.

[0046] In some embodiments of the present application, as understood in conjunction with Figures 1 and 5 , the lower plastic 100 may include: a first sub-lower plastic 100a and a second sub-lower plastic 100b, which may be spliced ​​along the length of the lower plastic 100. In addition to the first groove 111, the second groove 121, and the explosion-proof valve exhaust area 130, the lower plastic 100 may also include pole mounting holes, injection holes, blind holes for connection to the light cover, and other structural designs. The overall structure is relatively complex and long, making it relatively difficult to manufacture. The spliced ​​structural design can reduce the difficulty of preparing the lower plastic and also facilitates the assembly of the lower plastic and cover assembly. As some specific examples, the lower plastic 100 can be provided with both a positive pole mounting hole 151 and a negative pole mounting hole 152. In this case, one of the first sub-lower plastic 100a and the second sub-lower plastic 100b can be provided with a positive pole mounting hole 151, and the other can be provided with a negative pole mounting hole 152. As some other specific examples, the lower plastic 100 can be provided with an explosion-proof valve exhaust area 130. The explosion-proof valve exhaust area 130 can be provided on either the first sub-lower plastic 100a or the second sub-lower plastic 100b, or a portion can be provided on the first sub-lower plastic 100a and the other portion can be provided on the second sub-lower plastic 100b. The two portions can be spliced ​​together on the first sub-lower plastic 100a and the second sub-lower plastic 100b to form a complete explosion-proof valve exhaust area 130.

[0047] In some embodiments of the present application, the splicing method of the first lower plastic 100a and the second lower plastic 100b is not particularly limited. Those skilled in the art can flexibly select it according to actual needs, as long as the insulation effect between the optical cover 200 and the bare battery cell can be achieved. For example, the first lower plastic 100a and the second lower plastic 100b can be connected by overlapping or clipping. Among them, when the overlap connection is made, at the overlapping overlap of the first sub-lower plastic 100a and the second sub-lower plastic 100b, the width of the first sub-lower plastic 100a can be made narrower than the skirt of the second sub-lower plastic 100b. Therefore, during the assembly process of the cover assembly, the skirt of the second sub-lower plastic 100a can be used to limit the width direction of the first sub-lower plastic 100a. At the same time, the bare battery cell and the light cover 200 can be used to press against the lower plastic 100 in the thickness direction of the lower plastic 100 to limit the overlap, and the pole 700 and the pole mounting hole can be fixed in the length direction of the lower plastic 100 to limit the overlap.

[0048] In some embodiments of the present application, referring to FIG5 , the first sub-lower plastic 100a and the second sub-lower plastic 100b can each be independently provided with at least one first groove 111 and at least one second groove 121. The at least one first groove 111 and the at least one second groove 121 in the first sub-lower plastic 100a are continuously and alternately arranged along the length of the lower plastic 100, and the at least one first groove 111 and the at least one second groove 121 in the second sub-lower plastic 100b are continuously and alternately arranged along the length of the lower plastic 100. This arrangement not only helps to further improve the lateral exhaust effect and reduce the risk of poor exhaust, but also helps to prevent the battery cell from shaking and improve the internal stability of the battery cell. Furthermore, along the length of the lower plastic 100, the first groove 111 and the second groove 121 provided in the first sub-lower plastic 100a and the second sub-lower plastic 100b are directly or indirectly connected, which helps to further ensure the exhaust effect.

[0049] The second aspect of the present application proposes a cover assembly. According to an embodiment of the present application, the cover assembly includes the aforementioned lower plastic 100. Using the aforementioned lower plastic 100 in the cover assembly not only facilitates the convergence of gas produced by the battery cells to the bottom of the explosion-proof valve 400, meeting the exhaust requirements of the battery cells in the event of overheating and reducing the risk of poor exhaust, but also allows the lower plastic 100 to directly press against the bare battery cells when packaging the battery cells, thereby preventing the battery cells from shaking and improving the internal stability of the battery cells.

[0050] In some embodiments of the present application, as understood with reference to Figures 6 and 7 , the cover assembly further comprises: a light cover 200, comprising a third surface 210 and a fourth surface 220 disposed opposite each other along its thickness direction. The third surface 210 is provided with a protrusion 211, which is continuously disposed along the length of the light cover 200 and has an explosion-proof valve mounting hole 212 disposed thereon. The fourth surface 220 abuts against the first surface 110 of the lower plastic 100 and is provided with a groove 221 corresponding to the protrusion 211. It will be appreciated that the protrusion 211 is a continuous and uninterrupted structure along the length of the light cover 200, and the groove 221 is also a continuous and uninterrupted structure. The continuous and uninterrupted protrusions 211 and grooves 221 along the length of the light cover 200 can achieve a good reinforcement and air venting effect. This arrangement has the following beneficial effects: 1. The protrusion 211 located on the third side 210 of the optical cover 200 can act as a reinforcing rib, thereby improving the structural strength of the optical cover 200 and preventing the problem of bending when the optical cover 200 is long, which makes it impossible to assemble and weld. 2. The improved structural strength of the optical cover 200 also helps prevent deformation of the optical cover 200, which causes the explosion-proof valve 400 to be unable to open normally. 3. The groove 221 formed on the fourth side 220 of the optical cover 200 communicates with the installation position of the explosion-proof valve, which is conducive to the discharge of gas generated inside the battery. Furthermore, in the width direction of the cover assembly, at least a portion of the first groove 111 overlaps with the groove 221. This arrangement can further increase the lateral exhaust channel and ensure that the gas generated by the battery cell can be smoothly gathered under the explosion-proof valve.

[0051] In some embodiments of the present application, the specific type of the optical cover plate 200 may include, but is not limited to, a plain aluminum sheet, which may be made of either pure aluminum or an aluminum alloy. Selecting a plain aluminum sheet not only helps achieve lightweight batteries, but also helps reduce battery internal resistance, reduce overcurrent, and improve battery performance.

[0052] In some embodiments of the present application, the location of the explosion-proof valve mounting hole 212 on the protrusion 211 is not particularly limited, and those skilled in the art can flexibly select it according to actual needs, as long as it corresponds to the explosion-proof valve exhaust area 130 of the lower plastic. In addition, the optical cover 200 may also be provided with a positive electrode post through hole and / or a negative electrode post through hole, and the positive electrode post through hole and / or the negative electrode post through hole are correspondingly arranged with the positive electrode post mounting hole 151 and / or the negative electrode post mounting hole 152 in the lower plastic.

[0053] In some embodiments of the present application, the groove 221 and the protrusion 211 can be a stamped integrally formed structure, which is not only easy to process, but the protrusion formed by stamping can also act as a reinforcing rib, which can better improve the structural strength of the light cover.

[0054] In some embodiments of the present application, as will be understood with reference to FIG6 , the protrusions 211 may be disposed in the middle of the optical cover plate 200 along the width direction of the optical cover plate 200. Compared to disposing the protrusions 211 on either side of the optical cover plate 200 along its width direction, disposing the protrusions 211 in the middle of the optical cover plate 200 along its width direction is more conducive to the protrusions 211 functioning as reinforcing ribs, thereby further improving the structural strength of the optical cover plate 200. Furthermore, the protrusions 211 may be arranged symmetrically along the width direction of the optical cover plate 200. This arrangement allows the centerline of the protrusions 211 to coincide with the centerline of the optical cover plate 200, further enhancing the effect of the protrusions 211 on the structural strength of the optical cover plate 200.

[0055] In some embodiments of the present application, referring to FIG6 , the ratio of the extension distance of the protrusion 211 along the length of the optical cover 200 to the length of the optical cover 200 can be 0.2 to 0.9, for example, the ratio can be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9. Increasing the extension distance of the protrusion 211 along the length of the optical cover 200 not only helps further improve the structural strength of the optical cover 200, but also provides a longer groove 221, thereby increasing the exhaust space for gas generated by the battery cells and further facilitating the exhaust of gas generated by different areas of the battery cells. However, if the extension distance of the protrusion 211 along the length of the optical cover 200 is too short, the corresponding groove 221 is also short, which has limited ability to improve the structural strength of the optical cover 200 and improve the exhaust of the battery cells. By ensuring that the protrusion 211 extends along the length of the optical cover 200 to meet the specified configuration requirements, the structural strength of the optical cover 200 and the cell exhaust can be further improved, reducing the risk of poor cell exhaust. Furthermore, the ratio of the protrusion 211's extension along the length of the optical cover 200 to the length of the optical cover 200 can be 0.5 to 0.9. This configuration further increases the coverage of the protrusion 211 and the groove 221 on the optical cover 200, further improving the structural strength of the optical cover 200 and the cell exhaust.

[0056] In some embodiments of the present application, as understood with reference to FIG. 7 , the depth of the groove 221 may be 0.2 to 1 times the thickness of the optical cover 200, such as 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 times the thickness of the optical cover 200; and / or the height of the protrusion 211 may be 0.2 to 1 times the thickness of the optical cover 200, such as 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 times the thickness of the optical cover 200. If the depth of the groove 221 is too small, the gas flow channel formed on the optical cover 200 is also small, and the effect of improving gas exhaust is insignificant; if the height of the protrusion 211 is too small, the effect of improving the structural strength of the optical cover 200 is insignificant. Increasing the depth of the grooves 221 and the height of the protrusions 211 can improve the gas flow of the battery cells and enhance the structural strength of the optical cover 200. However, if the depth of the grooves 221 and the height of the protrusions 211 are too large, they will be difficult to manufacture through stamping. By controlling the depth of the gas-guiding grooves and the height of the protrusions to meet the given requirements, the corresponding optical cover 200 structure can be easily manufactured through stamping, while also achieving both good gas flow and structural strength.

[0057] In some embodiments of the present application, as understood with reference to FIG6 , the ratio of the extension distance of the protrusion 211 in the width direction of the optical cover 200 to the width of the optical cover 200 can be 0.05 to 0.95, for example, the ratio can be 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.95, etc. The protrusion 211 and the groove 221 are correspondingly arranged and can be formed by stamping. The protrusion 211 and the groove 221 have the same variation trend in the width, thickness, and length directions of the optical cover 200. Increasing the extension distance of the protrusion 211 across the width of the optical cover 200 increases the width of the groove 221 and the resulting gas flow path, thereby improving gas evacuation. However, if the extension distance of the protrusion 211 across the width of the optical cover 200 is too large, it will not only reduce the structural strength of the optical cover 200, but also affect the optical cover 200's ability to retain the lower plastic 100. By controlling the extension distance of the protrusion 211 across the width of the optical cover 200 to meet the given conditions, the optical cover 200 can achieve better gas evacuation and structural strength while also maintaining a good position retention effect on the lower plastic 100. Preferably, the ratio of the extension distance of the protrusion 211 across the width of the optical cover 200 to the width of the optical cover 200 can be between 0.2 and 0.9. Meeting this condition further balances the gas evacuation effect, structural strength, and position retention effect of the optical cover 200 on the lower plastic 100.

[0058] In some embodiments of the present application, as will be understood with reference to FIG6 , the extension distance of the protrusion 211 across the width of the optical cover 200 can be flexibly varied depending on the placement of the explosion-proof valve mounting hole 212 and other components. For example, as specific examples, the protrusion 211 can include a first region 211a and a second region 211b . The second region 211b can be provided with the explosion-proof valve mounting hole 212 . Along the width of the optical cover 200, the extension distance of the first region 211a can be smaller than the extension distance of the second region 211b . In actual operation, a larger width of the second region 211b facilitates the installation and welding of the explosion-proof valve 400 and its proper opening. A relatively smaller width of the first region 211a enhances the structural strength of the optical cover 200 while also providing a positive positioning effect on the lower plastic. Therefore, ensuring that the protrusion 211 meets these requirements further balances the optical cover 200's venting efficiency, structural strength, and positioning effect on the lower plastic 100.

[0059] In some embodiments of the present application, as understood with reference to FIG6 , the distance between the edge of the second region 211b and the edge of the explosion-proof valve mounting hole 212 may be no less than 1 mm. If the distance between the edge of the second region 211b (i.e., the raised edge) and the edge of the explosion-proof valve mounting hole 212 is too small, it will not only be detrimental to the installation and welding of the explosion-proof valve 400, but will also affect the gas flow path below the explosion-proof valve 400. Ensuring that the distance between the edge of the second region 211b and the edge of the explosion-proof valve mounting hole 212 meets the given requirements facilitates the assembly of the explosion-proof valve 400 while also ensuring a good exhaust effect.

[0060] In some embodiments of the present application, as will be understood with reference to FIG6 , the extension distance of the first region 211a in the width direction of the optical cover plate 200 may be no less than 2 mm, such as no less than 3 mm, 5 mm, 8 mm, or 10 mm, and the specific extension distance may be flexibly selected based on the actual conditions such as the width of the optical cover plate 200. Controlling the extension distance of the first region 211a in the width direction of the optical cover plate 200 to meet the given conditions can not only effectively improve the structural strength of the optical cover plate 200, but also facilitate the optical cover plate 200 to provide an effective gas flow channel.

[0061] In some embodiments of the present application, with reference to FIG6 , it can be understood that the ratio of the extension distance of the first region 211a in the width direction of the light cover 200 to the width of the light cover 200 can be 0.5-0.6, for example, 0.5, 0.52, 0.54, 0.56, 0.58 or 0.6, etc. By controlling the extension distance of the first region 211a in the width direction of the light cover 200 to meet the given conditions, a larger gas flow channel can be obtained to facilitate the convergence of gas generated by the battery cells to the bottom of the explosion-proof valve, and the structural strength of the light cover 200 can be enhanced.

[0062] In some embodiments of the present application, the ratio of the extension distance of the first region 211a along the length of the optical cover 200 to the extension distance of the protrusion 211 along the length of the optical cover 200 is 0.4 to 0.9, such as 0.4, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.9, etc., and can be flexibly selected based on the actual situation such as the length of the optical cover 200. Controlling the extension distance of the first region 211a along the length of the optical cover 200 to meet the given conditions can not only effectively further improve the structural strength of the optical cover 200, but also help the optical cover 200 to obtain a longer gas flow path, thereby facilitating the convergence of gas generated by the battery cells below the explosion-proof valve.

[0063] In some embodiments of the present application, as will be understood with reference to FIG6 , the protrusion 211 may further include a third region 211c , on which a liquid injection hole 213 may be provided. The extension distance of the third region 211c in the width direction of the optical cover 200 may be no less than the extension distance of the first region 211a . This arrangement not only facilitates the improvement of the air venting and structural strength of the optical cover 200 , but also facilitates the arrangement, injection operation, and sealing of the liquid injection hole 213 .

[0064] In some embodiments of the present application, referring to FIG8 , it is understood that the cover assembly includes not only the light cover 200 and the lower plastic 100 , but also conventional structural arrangements such as the upper plastic 300 , the explosion-proof valve 400 , the pressing block 500 , the sealing ring 600 , and the pole 700 .

[0065] The third aspect of the present application proposes an energy storage device. According to an embodiment of the present application, the energy storage device includes: a shell, a cover assembly and a bare battery cell, wherein the shell has an opening; the cover assembly closes the opening, and the cover assembly is the cover assembly of the above embodiment of the present application, or includes the lower plastic of the above embodiment of the present application; the bare battery cell is accommodated in the shell. The features and effects described for the above-mentioned lower plastic and cover assembly are also applicable to the energy storage device and will not be repeated here. In general, the energy storage device can not only better meet the exhaust requirements in the case of overheating of the battery cell, but also obtain better internal stability of the battery cell.

[0066] It should be noted that the specific type of the energy storage device is not particularly limited, and those skilled in the art can flexibly select it according to actual needs. For example, the energy storage device can be a single battery cell (refer to Figure 9 for understanding), or a battery module or battery pack including battery cells; for another example, the energy storage device can be a laminated battery or a wound battery, such as a wound square battery; for another example, the energy storage device can be a lithium battery or a sodium battery, and so on.

[0067] The fourth aspect of the present application proposes an electrical device. According to an embodiment of the present application, the electrical device includes the above-mentioned energy storage device. The features and effects described for the above-mentioned energy storage device are also applicable to the electrical device and will not be repeated here. It should be noted that there is no special restriction on the specific type of electrical device in this application, and those skilled in the art can flexibly choose according to actual conditions. For example, the electrical device may include but is not limited to vehicles, aircraft, household appliances, etc., wherein vehicles may include but are not limited to electric bicycles, electric tricycles, electric cars, and the like.

[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", 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 the present 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 one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0069] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A lower plastic, wherein: include: a first face, the first face comprising at least one first groove; The second surface is disposed opposite to the first surface along the thickness direction of the lower plastic, the second surface comprises at least one second groove, each of the second grooves is connected to at least one of the first grooves along the length direction of the lower plastic, and the bottom of the first groove extends to the second surface.

2. The lower plastic according to claim 1, wherein: include: A plurality of the first grooves and the second grooves are continuously and alternately arranged along the length direction of the lower plastic, and the total number of the first grooves and the second grooves continuously and alternately arranged is not less than 3.

3. The lower plastic according to claim 2, wherein: The first surface includes a plurality of the first grooves, and the plurality of the first grooves are arranged at intervals along the length direction of the lower plastic; and / or, The second surface includes a plurality of second grooves, and the plurality of second grooves are arranged at intervals along the length direction of the lower plastic.

4. The lower plastic according to any one of claims 1 to 3, wherein: At least one of the following conditions is met: The first surface is arranged away from the bare battery cell, and in the length direction of the lower plastic, the extension distance of the first groove is not greater than the extension distance of the second groove; The first groove and the second groove are respectively and independently provided with reinforcing ribs, and the reinforcing ribs are arranged along the length direction of the lower plastic; The ratio of the sum of the extension distances of the first groove and the second groove in the length direction of the lower plastic to the length of the lower plastic is not less than 0.5; The side wall thickness of the first groove and the side wall thickness of the second groove are independently 0.5 mm to 1.5 mm; A groove bottom of the second groove extends to the first surface.

5. The lower plastic according to claim 4, wherein: At least one of the following conditions is met: In the length direction of the lower plastic, the ratio of the extension distance of the first groove to the extension distance of the second groove is 0.2 to 1; The ratio of the sum of the extension distances of the first groove and the second groove in the length direction of the lower plastic to the length of the lower plastic is 0.5 to 0.8; The extension distance of the reinforcing rib in the width direction of the lower plastic is 0.5 mm to 1.5 mm; The first groove is provided with a first exhaust through hole, and the first exhaust through hole passes through the groove bottom of the first groove.

6. The lower plastic according to claim 1 or 5, wherein: The lower plastic is provided with an explosion-proof valve exhaust area, the explosion-proof valve exhaust area is provided with a second exhaust through hole penetrating the thickness direction of the lower plastic, and the explosion-proof valve exhaust area is connected with at least one of the first grooves and / or at least one of the second grooves in the length direction of the lower plastic.

7. The lower plastic according to claim 6, wherein: In the length direction of the lower plastic, a plurality of first grooves and second grooves are independently and continuously and alternately arranged on both sides of the exhaust area of ​​the explosion-proof valve.

8. The lower plastic according to claim 1 or 7, wherein: include: A first lower plastic and a second lower plastic, wherein the first lower plastic and the second lower plastic are spliced ​​and arranged along a length direction of the lower plastic.

9. The lower plastic according to claim 8, wherein: The first lower plastic and the second lower plastic are connected by overlapping or snapping; and / or, At least one first groove and at least one second groove are independently provided on the first sub-lower plastic and the second sub-lower plastic, respectively. At least one first groove and at least one second groove in the first sub-lower plastic are continuously and alternately arranged along the length direction of the lower plastic, and at least one first groove and at least one second groove in the second sub-lower plastic are continuously and alternately arranged along the length direction of the lower plastic.

10. A cover plate assembly, wherein: include: The lower plastic according to any one of claims 1 to 9.

11. The cover plate assembly according to claim 10, wherein: Also includes: The optical cover plate includes a third surface and a fourth surface which are arranged opposite to each other along the thickness direction thereof, the third surface is provided with a protrusion, the protrusion is continuously arranged along the length direction of the optical cover plate, and the protrusion is provided with an explosion-proof valve mounting hole; the fourth surface abuts against the first surface of the lower plastic, and is provided with a groove arranged corresponding to the protrusion.

12. The cover plate assembly according to claim 11, wherein: In the width direction of the light cover, the protrusions are provided in the middle of the light cover; and / or the protrusions are symmetrically arranged along the width direction of the light cover.

13. The cover plate assembly according to claim 11 or 12, wherein: At least one of the following conditions is met: The ratio of the extension distance of the protrusion in the length direction of the optical cover plate to the length of the optical cover plate is 0.2 to 0.9; The ratio of the extension distance of the protrusion in the width direction of the optical cover plate to the width of the optical cover plate is 0.05 to 0.95; The depth of the groove is 0.2 to 1 times the thickness of the optical cover plate; The protrusion height of the protrusion is 0.2 to 1 times the thickness of the optical cover plate.

14. The cover plate assembly according to claim 11 or 12, wherein: The protrusion includes a first area and a second area, the second area is provided with an explosion-proof valve mounting hole, and in the width direction of the optical cover plate, the extension distance of the first area is smaller than the extension distance of the second area; and / or, The ratio of the extension distance of the protrusion in the length direction of the light cover plate to the length of the light cover plate is 0.5 to 0.

9.

15. The cover plate assembly according to claim 14, wherein: At least one of the following conditions is met: The distance between the edge of the second area and the edge of the explosion-proof valve installation hole is not less than 1 mm; The ratio of the extension distance of the first area in the width direction of the optical cover to the width of the optical cover is 0.5 to 0.6; The extension distance of the first area in the width direction of the optical cover is not less than 2 mm; A ratio of an extension distance of the first region in the length direction of the optical cover plate to an extension distance of the protrusion in the length direction of the optical cover plate is 0.4 to 0.9; The protrusion further includes a third area, and a liquid injection hole is provided on the third area. In the width direction of the optical cover plate, the extension distance of the third area is not less than the extension distance of the first area.

16. An energy storage device, wherein: include: a housing having an opening; A cover plate assembly, the cover plate assembly closes the opening, the cover plate assembly is the cover plate assembly according to any one of claims 10 to 15, or comprises the lower plastic according to any one of claims 1 to 9; A bare battery cell is contained in the shell.

17. An electrical device, wherein: include: The energy storage device of claim 16.

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