Battery case and vehicle

Abstract

Disclosed in the present application are a battery case and a vehicle. The battery case comprises a case body and a beam body. The case body at least comprises a case bottom wall and case side walls, the case bottom wall and the case side walls enclosing an accommodating cavity, and the accommodating cavity being used for accommodating batteries. The beam body is fixedly arranged within the accommodating cavity, and the beam body comprises an upper beam and a lower beam that are jointed, the upper beam and the lower beam each having a U-shaped structure, and the opening of the upper beam and the opening of the lower beam being arranged facing each other; at least part of beam side walls of the upper beam overlap at least part of beam side walls of the lower beam; at least part of the overlap sections of the beam side walls of the upper and lower beams is arranged in a direction perpendicular to the case bottom wall; the beam side walls of the lower beam are located between the two beam side walls of the upper beam; and a ratio L1 / L2 of the height L1 of the beam side walls of the lower beam to the height L2 of the upper beam is 0.06-1. The battery case has reduced costs while having improved structural strength.

Description

Battery housing and vehicle

[0001] This application claims priority to Chinese Patent Application No. 202411428317.5, filed on October 14, 2024, entitled "Battery Box and Vehicle", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, and in particular to a battery housing and vehicle. Background Technology

[0003] As a key component that carries the battery cells, the battery pack housing needs to be designed with safety, reliability, and durability in mind, as well as cost considerations.

[0004] How to improve the structural strength of the battery box while saving costs is a research topic for those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a battery housing and vehicle that can improve structural strength while reducing cost.

[0006] To address the aforementioned technical problems, this application provides a battery housing, comprising a housing body and a beam body;

[0007] The box body includes at least a bottom wall and a side wall, the bottom wall and the side wall forming a receiving cavity for accommodating the battery; the beam is fixed inside the receiving cavity;

[0008] The beam body includes a spliced ​​upper beam and a lower beam, both of which are U-shaped. The openings of the upper beam and the lower beam face each other. At least a portion of the side wall of the upper beam overlaps with at least a portion of the side wall of the lower beam. At least a portion of the overlapping section of the side wall of the upper beam and the side wall of the lower beam is located in a direction perpendicular to the bottom wall of the box.

[0009] The sidewall of the lower beam is located between the two sidewalls of the upper beam;

[0010] The ratio of the height L1 of the side wall of the lower beam to the height L2 of the upper beam, L1 / L2, is 0.06 to 1.

[0011] This application also provides a vehicle, including a vehicle body and a battery box mounted on the vehicle body, wherein the battery box is the battery box described above.

[0012] The battery box provided in this application embodiment can be used in vehicles. The battery box improves the beam structure inside its body. The beam is made of two U-shaped beams spliced ​​together, which is a split structure that avoids mold costs. After splicing, at least a portion of the side beam wall of the upper beam overlaps with at least a portion of the side beam wall of the lower beam, and at least a portion of the overlapping section is perpendicular to the bottom wall of the box. At the overlapping position, the beam wall thickness increases, which can increase the support strength of the beam and avoid the problem of insufficient support strength when the beam is high. When this beam is applied to the battery box, it helps to maintain the shape of the battery box when the battery box is subjected to external pressure or impact, which can reduce the probability of battery box deformation. This can avoid the battery cell assembly from being squeezed and causing short circuits and other adverse phenomena, and can play a better protective role for the battery cell assembly, which helps to improve safety.

[0013] Meanwhile, the ratio of the height L1 of the side beam wall of the lower beam to the height L2 of the upper beam, L1 / L2, is 0.06 to 1. In this way, while avoiding adding extra weight to the battery box, the supporting strength of the beam to the box body can be guaranteed. Attached Figure Description

[0014] Figure 1 is a schematic diagram of the battery box structure provided in an embodiment of this application;

[0015] Figure 2 is a structural schematic diagram of the beam in one embodiment provided in this application;

[0016] Figure 3 is a cross-sectional schematic diagram of the beam shown in Figure 2;

[0017] Figure 4 is a cross-sectional schematic diagram of the fit between the beam and the bottom wall of the box in a specific embodiment;

[0018] Figure 5 is a structural schematic diagram of the connection between the fifth beam and the third beam in a specific embodiment;

[0019] Figure 6 is a structural schematic diagram of the connection between the fifth beam and the side wall of the first box in a specific embodiment.

[0020] Explanation of reference numerals in the attached drawings: Battery box 10; Box body 20, Box bottom wall 21, First box side wall 221, Through hole 2211, Second box side wall 222, Third box side wall 223, Fourth box side wall 224; First beam 301, Second beam 302, Third beam 303, Fourth beam 304, Fifth beam 305; Beam body 30, Upper beam 31, First side beam wall 311, Top beam wall 312, Flanged edge 313, Lower beam 32, Second side beam wall 321, Bottom beam wall 322. Detailed Implementation

[0021] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] The ordinal numbers used in this article, such as first and second, are used to distinguish different parts with the same name and do not indicate a specific order or primary / secondary relationship.

[0023] The directional terms used in this document, such as "top" and "bottom," are defined based on the position of the components in the diagram and the relative positions of the components. The use of these directional terms is merely for the clarity and convenience of describing the technical solution and should not be construed as a limitation on the scope of protection.

[0024] Please refer to Figure 1, which shows a schematic diagram of the battery housing in one embodiment.

[0025] In this embodiment, the battery box 10 includes a box body 20, which is generally an open frame structure. The box body 20 includes a bottom wall 21 and side walls surrounding the bottom wall 21.

[0026] In the illustrated example, the box body 20 is roughly rectangular in shape and includes four box side walls, namely the first box side wall 221, the second box side wall 222, the third box side wall 223 and the fourth box side wall 224. The first box side wall 221 and the third box side wall 223 are arranged opposite to each other, and the second box side wall 222 and the fourth box side wall 224 are arranged opposite to each other.

[0027] In other embodiments, the shape of the box body 20 can also be other forms, such as a racetrack shape, and the side walls of the box can be matched accordingly.

[0028] The bottom wall 21 and the side wall of the box body 20 form a receiving cavity, which is used to house the battery. The receiving cavity can also be used to house control components related to the battery.

[0029] The battery housing 10 may also include a cover (not shown in the figure), which is used to seal the opening of the housing body 20 to form a closed chamber to protect the battery and related control components housed in the housing body 20.

[0030] In this embodiment, the battery box 10 also includes several beams fixed in the receiving cavity. These beams can divide the receiving cavity to form different spaces, which facilitates the installation of different components contained in the box body 20. At the same time, these beams can also improve the structural strength of the battery box 10.

[0031] In the example shown in Figure 1, the battery box 10 is provided with five beams, namely the first beam 301, the second beam 302, the third beam 303, the fourth beam 304 and the fifth beam 305.

[0032] The third beam 303 is arranged close to the side wall 221 of the first box. The two ends of the third beam 303 can be fixedly connected to the side wall 222 of the second box and the side wall 224 of the fourth box, respectively. The third beam 303, the side wall 221 of the first box, the side wall 222 of the second box and the side wall 224 of the fourth box can enclose a space for installing control components, etc.

[0033] The fourth beam 304 is arranged adjacent to the side wall 223 of the third box. The two ends of the fourth beam 304 can be fixedly connected to the side wall 222 of the second box and the side wall 224 of the fourth box, respectively. The extension directions of the first beam 301 and the second beam 302 are consistent with the extension directions of the side wall 222 of the second box and the side wall 224 of the fourth box. The two ends of the first beam 301 and the second beam 302 can be fixedly connected to the third beam 303 and the fourth beam 304, respectively. The third beam 303, the side wall 222 of the second box, the fourth beam 304 and the first beam 301 can enclose a space for accommodating the battery. The second beam 302, the fourth beam 304, the side wall 224 of the fourth box and the third beam 303 can also enclose a space for accommodating the battery.

[0034] The fifth beam 305 is located between the first box side wall 221 and the third beam 303.

[0035] In other embodiments, the specific number and arrangement of beams in the battery box 10 are set according to actual application requirements and are not limited to those shown in Figure 1.

[0036] This implementation scheme focuses on improving the structure of the beams in the battery box 10. In application, at least one beam in the box body 20 can adopt the beam body 30 provided in this implementation scheme. For example, as shown in Figure 1, at least one of the first beam 301, the second beam 302, the third beam 303, the fourth beam 304 and the fifth beam 305 adopts the beam body 30 provided in this implementation scheme.

[0037] Please refer to Figures 2 and 3 together. Figure 2 is a structural schematic diagram of the beam in one embodiment of this application, and Figure 3 is a cross-sectional schematic diagram of the beam shown in Figure 2.

[0038] Here, we take the fifth beam 305, which adopts the improved beam 30 of this implementation scheme, as an example. That is, the beam 30 shown in Figure 2 can be understood as the fifth beam 305 in Figure 1.

[0039] In other embodiments, the remaining beams may also adopt the beam structure 30 shown in Figure 2, which will not be described in detail here.

[0040] As shown in Figure 2, the beam 30 provided in this embodiment includes a spliced ​​upper beam 31 and a lower beam 32. Both the upper beam 31 and the lower beam 32 have a U-shaped structure. The openings of the upper beam 31 and the lower beam 32 are arranged facing each other, that is, the opening of the upper beam 31 faces downward and the opening of the lower beam 32 faces upward. At least a portion of the side beam wall of the upper beam 31 overlaps with at least a portion of the side beam wall of the lower beam 32.

[0041] The U-shaped structure here refers to a structure consisting of a base plate (or top plate) and side plates extending from both sides of the base plate (or top plate) at an angle to the base plate (or top plate).

[0042] For ease of explanation, the side beam wall of the upper beam 31 is referred to as the first side beam wall 311, and the side beam wall of the lower beam 32 is referred to as the second side beam wall 321. The upper beam 31 also includes a top beam wall 312 connecting the two first side beam walls 311, and the lower beam 32 also includes a bottom beam wall 322 connecting the two second side beam walls 321.

[0043] After the upper beam 31 and the lower beam 32 are spliced ​​together to form the beam body 30, the first side beam wall 311 and the second side beam wall 321 have at least a partially overlapping section, and at least a portion of the overlapping section is arranged in a direction perpendicular to the bottom wall 21 of the box.

[0044] The beam 30 is constructed by splicing two U-shaped beam structures, forming a split structure that avoids mold costs. After splicing, at least a portion of the first side wall 311 of the upper beam 31 overlaps with at least a portion of the second side wall 321 of the lower beam 32. At the overlap, the beam wall thickness of the beam 30 increases, thereby increasing the support strength of the beam 30 and avoiding the problem of insufficient support strength when the beam 30 is high. When the beam 30 is applied to the battery box 10, it helps to maintain the shape of the battery box 10 when it is subjected to external pressure or impact, reducing the probability of deformation of the battery box 10. This avoids short circuits and other adverse phenomena caused by battery compression, providing better protection for the battery and improving safety.

[0045] As shown in Figure 3, the height of the second side beam wall 321 of the lower beam 32 is L1, and the height of the upper beam 31 is L2. In one implementation, the ratio of the height L1 of the second side beam wall 321 to the height L2 of the upper beam 31, L1 / L2, is 0.06 to 1.

[0046] In this text, the height L1 of the second side beam wall 321 is the distance between the top surface of the second side beam wall 321 and the top surface of the bottom beam wall 322 in the direction perpendicular to the bottom wall 21 of the box; the height L2 of the upper beam 31 is the distance between the top surface of the top beam wall 312 of the upper beam 31 and the bottom surface of the first side beam wall 311 in the direction perpendicular to the bottom wall 21 of the box.

[0047] The above configuration ensures the supporting strength of the beam 30 to the box body 20 while avoiding adding extra weight to the battery box 10.

[0048] In application, the ratio L1 / L2 should not be too small or too large. If the ratio L1 / L2 is too large, it will result in material waste and increase the weight of the beam 30 while maintaining the required support strength, which is not conducive to the lightweighting of the battery box 10. If the ratio L1 / L2 is too small, the support strength of the beam 30 will be insufficient, making the battery box 10 prone to deformation when subjected to external pressure. For example, the ratio L1 / L2 can be 0.06, 0.08, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1, that is, the ratio L1 / L2 can be any value from 0.06 to 1.

[0049] In practice, the ratio L1 / L2 of the height L1 of the second side beam wall 321 to the height L2 of the upper beam 31 can be determined in combination with the materials of the upper beam 31 and the lower beam 32.

[0050] For example, when the upper beam 31 and the lower beam 32 are made of steel, that is, when the beam body 30 is a steel structure, the ratio L1 / L2 of the height L1 of the second side beam wall 321 to the height L2 of the upper beam 31 can be 0.06 to 1. Considering that steel has high structural strength, the ratio L1 / L2 can be set relatively small in this case.

[0051] In one implementation, both the upper beam 31 and the lower beam 32 can be made of sheet metal, which is formed by bending, making it easy to process and relatively inexpensive.

[0052] As shown in Figure 3, the thickness of the first side beam wall 311 of the upper beam 31 is M1, and the thickness of the second side beam wall 321 of the lower beam 32 is M2. When the beam body 30 is installed, M1, M2, and L1 satisfy the following relationship: (M1 / L1)×M2=0.01~2. Specifically, the thickness of the first side beam wall 311 and the thickness of the second side beam wall 321 can both be referenced to the minimum thickness.

[0053] For example, the ranges of values ​​for M1, M2, L1, and (M1 / L1)×M2 can be shown in the table below:

[0054] The thickness of the sheet metal determines the length of the bending zone. That is, when the sheet metal is bent to form the upper beam 31 or the lower beam 32, the thickness of the sheet metal determines the height of the side beam wall (including the first side beam wall 311 and the second side beam wall 321). When the sheet metal is thicker, the height of the bending zone can be relatively shorter to avoid redundant design, material waste and additional weight of the battery box 10. When the sheet metal is thinner, the height of the bending zone can be relatively longer to ensure support strength.

[0055] In one implementation, the second side beam wall 321 of the lower beam 32 is located inside the first side beam wall 311 of the upper beam 31. Here, "inside" refers to the side closer to the beam cavity of the upper beam 31, that is, the second side beam wall 321 of the lower beam 32 is located between the two first side beam walls 311 of the upper beam 31.

[0056] As shown in Figures 2 and 3, after the second side beam wall 321 of the lower beam 32 is placed inside the first side beam wall 311 of the upper beam 31, the overlapping part of the second side beam wall 321 and the first side beam wall 311 is located inside the beam body 30. After being applied to the battery box 10, it will not occupy the storage space of the box body 20, which can improve the space utilization of the battery box 10 and facilitate the arrangement of related structures.

[0057] Please also refer to Figure 4, which is a cross-sectional schematic diagram of the fit between the beam and the bottom wall of the box in a specific embodiment.

[0058] In one implementation, the beam 30 is welded and fixed to the bottom wall 21 of the box body 20, and the upper beam 31 and lower beam 32 of the beam 30 are welded and fixed.

[0059] In a specific implementation, in the height direction perpendicular to the bottom wall 21 of the box, the lower beam 32 is provided with a non-overlapping part that does not overlap with the upper beam 31 near the bottom wall 21, that is, the outer wall surface of the bottom beam wall 322 of the lower beam 32 is lower than the bottom wall surface of the first side beam wall 311 of the upper beam 31.

[0060] With the above setup, the upper beam 31 and lower beam 32 of the beam body 30 can be welded to the bottom wall 21 of the box in one welding process. The welding point is between the outer wall surface of the non-overlapping part of the lower beam 32, the bottom wall surface of the first side beam wall 311, and the bottom wall 21 of the box. After welding, a weld seam is formed, which is referred to here as the first weld line 1S, as shown in Figure 4. In this way, the welding efficiency can be improved, effectively enhancing the assembly efficiency of the battery box 10.

[0061] For example, the first weld line 1S can be a continuous weld extending along the length of the beam 30. This can improve the connection strength between the upper beam 31, the lower beam 32, and the box bottom wall 21.

[0062] For example, the first weld line 1S may also include multiple weld points spaced apart along the length of the beam 30. This can save costs.

[0063] As shown in Figure 3, the distance between the bottom wall surface of the non-overlapping part of the lower beam 32 (i.e. the outer wall surface of the bottom beam wall 322) and the bottom wall surface of the first side beam wall 311 of the upper beam 31 is H1. The ratio of this distance H1 to the height L1 of the second side beam wall 321 of the lower beam 32, L1 / H1, is 1 to 800.

[0064] Referring to Figure 4, the non-overlapping portion of the lower beam 32 forms a clearance space between the first side beam wall 311 and the box bottom wall 21. This clearance space allows the aforementioned upper beam 31, lower beam 32, and box bottom wall 21 to be welded in a single welding process. The size of this clearance space is related to the welding strength. When the height of the second side beam wall 321 increases, the clearance distance H1 should also increase to ensure welding strength.

[0065] In application, the ratio L1 / H1 should not be too large or too small. If it is set too large, the welding strength cannot be guaranteed; if it is set too small, it will result in design redundancy and waste. The above-mentioned setting of the ratio L1 / H1 can balance welding strength and cost.

[0066] In application, the ratio L1 / H1 can be determined by referring to the welding method, beam material, and welding material.

[0067] In one implementation, when the ratio L1 / L2 of the height L1 of the second side beam wall 321 of the lower beam 32 and the height L2 of the upper beam 31 is 0.8 to 1, the second side beam wall 321 is welded and fixed to the first side beam wall 311.

[0068] The welding position between the second side beam wall 321 and the first side beam wall 311 can be set as needed, as shown in Figure 4. The top surface of the second side beam wall 321 is welded to the first side beam wall 311, forming a weld seam, which is referred to here as the second weld line 2S. This ensures the connection strength between the upper beam 31 and the lower beam 32, effectively improving the support strength of the beam body 30 for the battery box 10.

[0069] For example, the second weld line 2S can be a continuous weld extending along the length of the beam 30. This can improve the connection strength between the upper beam 31 and the lower beam 32.

[0070] For example, the second weld line 2S may also include multiple weld points spaced apart along the length of the beam 30. This can save costs.

[0071] In one implementation, when the position of the second weld line 2S is higher than half the height L1 of the second side beam wall 321 of the lower beam 32, the ratio L1 / L2 of the height L1 of the second side beam wall 321 of the lower beam 32 to the height L2 of the upper beam is 0.07 to 1; when the position of the second weld line 2S is lower than half the height L1 of the second side beam wall 321 of the lower beam 32, the ratio L1 / L2 of the height L1 of the second side beam wall 321 of the lower beam 32 to the height L2 of the upper beam is 0.06 to 1.

[0072] The welding position between the second side beam wall 321 and the first side beam wall 311, i.e. the height of the second weld line 2S, determines the support strength of the beam 30. Relatively speaking, the higher the height of the second weld line 2S, the higher the height requirement for the lower beam 32.

[0073] In one implementation, as shown in Figure 2, at least one end of at least one beam wall of the upper beam 31 has a flange 313 extending in a direction away from the center of the upper beam 31.

[0074] In other words, the beam wall of the upper beam 31 includes two first side beam walls 311 and a top beam wall 312, and at least one end of at least one of the two first side beam walls 311 and the top beam wall 312 has a flange 313 extending in a direction away from the center of the upper beam 31.

[0075] In applications, the 313 flange can also be formed by bending.

[0076] After the above settings are made, the beam 30 can be welded and fixed to the side wall of the adjacent box body 20 or other box beams set in the box body 20 through the flange 313 at its end in the length direction.

[0077] The following description uses the fifth beam 305 shown in Figure 1 as an example of the beam 30 structure described above. Please refer to Figures 5 and 6 together. Figure 5 is a structural schematic diagram of the connection between the fifth beam and the third beam in a specific embodiment, and Figure 6 is a structural schematic diagram of the connection between the fifth beam and the side wall of the first box in a specific embodiment.

[0078] In the example shown in Figure 1, the fifth beam 305 is located between the first box side wall 221 and the third beam 303. The two ends of the fifth beam 305 can be fixedly connected to the first box side wall 221 and the third beam 303 respectively, so as to improve the overall structural strength of the battery box 10.

[0079] When the fifth beam 305 adopts the beam body 30 structure shown in Figures 2 to 4, the beam body 30 can be fixedly connected to the first box side wall 221 or the third beam 303 through the flange 313.

[0080] As shown in Figure 5, the upper beam 31 of the beam body 30 has three flanges 313 at one end near the third beam 303. That is, the ends of the two first side beam walls 311 and the top beam wall 312 near the third beam 303 are all provided with flanges 313. These three flanges 313 can be fitted and fixed to the side walls of the third beam 303. The fixing method can be welding, which is convenient to implement and has high connection reliability.

[0081] As shown in Figure 6, the upper beam 31 of the beam body 30 has a flange 313 at one end near the first box side wall 221. This flange 313 is formed by bending the end of a first side beam wall 311 of the upper beam 31 near the first box side wall 221. In the illustrated example, the aforementioned arrangement is related to the structure of the first box side wall 221. The first box side wall 221 has a through hole 2211 near the beam body 30, and the first box side wall 221 has a stepped structure. Therefore, only one flange 313 of the first side beam wall 311 of the upper beam 31 can be fixedly engaged with the first box side wall 221.

[0082] In other embodiments, the number and position of the flanges 313 provided at the end of the upper beam 31 can be determined as needed. For example, flanges 313 can be provided only on the top beam wall 312 or only on the first side beam wall 311.

[0083] In a specific implementation, when the beam 30 is a box beam extending along the width direction of the box body 20, taking Figure 1 as an example, when the beam 30 is a box beam with the same extension direction as the first box side wall 221 or the third box side wall 223, the ratio L1 / L2 of the height L1 of the second side beam wall 321 of the lower beam 32 and the height L2 of the upper beam 31 is 0.06 to 1.

[0084] In a specific implementation, when the beam 30 is a box longitudinal beam extending along the length direction of the box body 20, taking Figure 1 as an example, when the beam 30 is a box longitudinal beam with the same extension direction as the second box side wall 222 or the fourth box side wall 224, the ratio L1 / L2 of the height L1 of the second side beam wall 321 of the lower beam 32 and the height L2 of the upper beam 31 is 0.08 to 1.

[0085] Generally speaking, the length of the longitudinal beam of the box body is greater than the length of the transverse beam of the box body. When the beam 30 is used as the longitudinal beam of the box body, the height L1 of the second side beam wall 321 of the lower beam 32 can be set relatively large to ensure the support strength of the box body 20. When the beam 30 is used as the transverse beam of the box body, the height L1 of the second side beam wall 321 of the lower beam 32 can be set relatively small to avoid redundant design while taking into account the support effect.

[0086] In a specific implementation, the housing cavity of the box body 20 includes a battery compartment and an electrical compartment. The battery compartment is used to store batteries, and the electrical compartment is used to store control components, etc. When the beam body 30 is used to separate the battery compartment and the electrical compartment, the ratio L1 / L2 of the height L1 of the second side beam wall 321 of the lower beam 32 and the height L2 of the upper beam 31 is 0.06 to 1.

[0087] In a specific implementation, the housing cavity of the box body 20 includes two or more battery compartments, such as a first battery compartment and a second battery compartment. When the beam body 30 is used to separate the first battery compartment and the second battery compartment, the ratio L1 / L2 of the height L1 of the second side beam wall 321 of the lower beam 32 and the height L2 of the upper beam 31 is 0.08 to 1.

[0088] When beam 30 is used to divide the battery compartment, the batteries inside the battery compartment may expand and exert pressure on beam 30. In this case, the height L1 of the second side wall 321 of the lower beam 32 can be set relatively large to improve the support strength of beam 30. Relatively speaking, when beam 30 has an electrical compartment on only one side, such as when beam 30 is used to separate the battery compartment and the electrical compartment, the height L1 of the second side wall 321 of the lower beam 32 can be set relatively small. When beam 30 has electrical compartments on both sides, such as when beam 30 is used to separate two battery compartments, the height L1 of the second side wall 321 of the lower beam 32 can be set relatively large.

[0089] This application also provides a vehicle, which includes a vehicle body and a battery box installed on the vehicle body. The battery box is the same as the one provided in the above embodiments and has the corresponding technical effects, which will not be repeated here.

[0090] For example, the battery pack can be installed at the bottom of the vehicle body.

[0091] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A battery case characterized by comprising: Including the box body and the beams; The box body includes at least a bottom wall and a side wall, the bottom wall and the side wall forming a receiving cavity for accommodating the battery; the beam is fixed inside the receiving cavity; The beam body includes a spliced ​​upper beam and a lower beam, both of which are U-shaped. The openings of the upper beam and the lower beam face each other. At least a portion of the side wall of the upper beam overlaps with at least a portion of the side wall of the lower beam. At least a portion of the overlapping section of the side wall of the upper beam and the side wall of the lower beam is located in a direction perpendicular to the bottom wall of the box. The sidewall of the lower beam is located between the two sidewalls of the upper beam; The ratio of the height L1 of the side wall of the lower beam to the height L2 of the upper beam, L1 / L2, is 0.06 to 1. The thickness M1 of the side wall of the upper beam, the thickness M2 of the side wall of the lower beam, and the height L1 of the side wall of the lower beam satisfy the following relationship: (M1 / L1)×M2=0.01~2, The beam is welded and fixed to the bottom wall of the box body, and the upper beam is welded and fixed to the lower beam; In the height direction perpendicular to the bottom wall of the box, the lower beam is provided with a non-overlapping part near the bottom wall of the box, which is not overlapping with the upper beam. The outer wall surface of the non-overlapping part, the bottom wall surface of the side beam wall of the upper beam, and the bottom wall of the box are welded together by a first welding line.

2. The battery pack of claim 1, wherein The distance between the bottom wall of the non-overlapping part and the bottom wall of the side beam of the upper beam is H1, and the ratio of the distance H1 to the height L1 of the side beam of the lower beam, L1 / H1, is 1 to 800.

3. The battery pack of claim 1, wherein, When the ratio L1 / L2 of the height L1 of the lower beam and the height L2 of the upper beam is 0.8 to 1, the side wall of the lower beam and the side wall of the upper beam are welded and fixed together by a second welding line.

4. The battery pack of claim 3, wherein When the position of the second weld line is higher than 1 / 2 of the height L1 of the side wall of the lower beam, the ratio L1 / L2 of the height L1 of the side wall of the lower beam and the height L2 of the upper beam is 0.07 to 1.

5. The battery pack of claim 3, wherein When the position of the second weld line is lower than 1 / 2 of the height L1 of the side wall of the lower beam, the ratio L1 / L2 of the height L1 of the side wall of the lower beam and the height L2 of the upper beam is 0.06 to 1.

6. The battery pack of any one of claims 1-5, wherein, At least one end of at least one beam wall of the upper beam has a flange extending away from the upper beam, the flange being used for welding and fixing to other box beams within the receiving cavity.

7. The battery pack of any one of claims 1-5, wherein, The beam is made of steel, and the ratio of the height L1 of the side wall of the lower beam to the height L2 of the upper beam, L1 / L2, is 0.06 to 1.

8. The battery pack of any one of claims 1-5, wherein, When the beam is a box beam extending along the width direction of the box body, the ratio L1 / L2 of the height L1 of the side wall of the lower beam and the height L2 of the upper beam is 0.06 to 1.

9. The battery pack of any one of claims 1-5, wherein, When the beam is a box-shaped longitudinal beam extending along the length of the box body, the ratio L1 / L2 of the height L1 of the side wall of the lower beam and the height L2 of the upper beam is 0.08 to 1.

10. The battery pack of any one of claims 1-5, wherein, The accommodating cavity includes a battery compartment and an electrical compartment. When the beam is used to divide the battery compartment and the electrical compartment, the ratio L1 / L2 of the height L1 of the side wall of the lower beam and the height L2 of the upper beam is 0.06 to 1.

11. The battery pack of any one of claims 1-5, wherein, The accommodating cavity includes a first battery compartment and a second battery compartment. When the beam is used to divide the first battery compartment and the second battery compartment, the ratio L1 / L2 of the height L1 of the side wall of the lower beam and the height L2 of the upper beam is 0.08 to 1.

12. Vehicle, characterized in that It includes a vehicle body and a battery box installed on the vehicle body, wherein the battery box is the battery box as described in any one of claims 1-11.

Images