Battery box beam, battery box and battery module

Abstract

The application provides a battery box beam, a battery box and a battery module, and relates to the technical field of batteries, and aims to improve the technical problem that the connection strength of a rolled battery box beam at a connection position is insufficient and separation may occur. The battery box beam comprises a main body wall; a first beam wall connected to one end of the main body wall, the first beam wall comprising a first pressure bearing section, the first pressure bearing section being arranged opposite the main body wall; and extending towards the first pressure bearing section, the second pressure bearing section having an overlapping portion with the first pressure bearing section, and the second pressure bearing section and the first pressure bearing section being fixedly connected at the overlapping portion. The application can meet the requirements of lightweight and strength of the battery module.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery box beam, a battery box and a battery module. BACKGROUND

[0002] In the related art, a rolling process is used to bend a plate to form a closed structure, and then horizontal welding is used at the connection of the two ends of the plate to form an anti-expansion beam. Although this method effectively reduces the welding position and improves the ability to withstand expansion and extrusion, the welding surface (welding seam) is in the same direction as the extrusion force when the battery cell expands, which causes the welding seam between the two end walls of the anti-expansion beam to crack easily, and the welding surface to separate. Therefore, the anti-expansion and extrusion performance of the anti-expansion beam needs to be improved. SUMMARY

[0003] Embodiments of the present application provide a battery box beam, a battery box and a battery module to improve the technical problem of the anti-expansion and extrusion performance of the anti-expansion beam.

[0004] In a first aspect, embodiments of the present application provide a battery box beam, which is a rolled steel beam and includes:

[0005] a main body wall;

[0006] a first beam wall connected to one end of the main body wall, the first beam wall including a first pressure bearing section, the first pressure bearing section being oppositely arranged with the main body wall;

[0007] a second beam wall connected to the other end of the main body wall, the second beam wall including a second pressure bearing section, the second pressure bearing section being oppositely arranged with the main body wall and extending towards the first pressure bearing section, the second pressure bearing section and the first pressure bearing section having an overlapping portion, and the second pressure bearing section and the first pressure bearing section being fixedly connected at the overlapping portion.

[0008] In some embodiments of the present application, the first pressure bearing section includes a first extension section, a second extension section and a bending section, the first extension section and the second extension section being connected by the bending section, and the first extension section and the second extension section having the same extension direction, the bending section being bent from the first extension section towards the main body wall to make the second extension section closer to the main body wall than the first extension section, the first extension section and the second extension section collectively defining a connection portion, and the end portion of the second pressure bearing section close to the first pressure bearing section being arranged at the connection portion and being overlapped and fixedly welded with the second extension section.

[0009] In some embodiments of the present application, the first extension section has a first surface facing away from the main body wall, the second pressure bearing section has a second surface facing away from the main body wall, and the first surface and the second surface are coplanar.

[0010] In some embodiments of the present application, the two ends of the bending section are respectively connected with the first extension section and the second extension section in a circular arc transition.

[0011] In some embodiments of the present application, the first extension section has a first surface facing away from the main body wall, the second pressure bearing section has a second surface facing away from the main body wall, and the first surface is coplanar with the second surface.

[0012] In some embodiments of the present application, the first beam wall further comprises a first connecting section connected between the first pressure bearing section and the main body wall, the second beam wall further comprises a second connecting section connected between the second pressure bearing section and the main body wall, and the second connecting section is arranged opposite to the first connecting section, and the main body wall, the first connecting section, the first pressure bearing section, the second pressure bearing section and the second connecting section enclose a beam cavity.

[0013] In some embodiments of the present application, the first beam wall further comprises a buffer section connected with the first pressure bearing section at an end close to the second pressure bearing section and extending towards the main body wall, and the buffer section is configured to support the first pressure bearing section and the second pressure bearing section when the first pressure bearing section and the second pressure bearing section are under pressure, and to slide along the main body wall to buffer the extrusion pressure.

[0014] In some embodiments of the present application, the buffer section comprises a support section and an abutting section, the support section is connected between the first pressure bearing section and the abutting section, and the abutting section is parallel to and connected with the main body wall.

[0015] In some embodiments of the present application, the abutting section abuts with the main body wall, and the abutting section is configured to slide along the main body wall to buffer the extrusion pressure when the first pressure bearing section and the second pressure bearing section are under pressure.

[0016] In some embodiments of the present application, the abutting section is fixedly connected with the main body wall, and the abutting section is configured to change from fixed connection to sliding connection with the main body wall and slide along the main body wall to buffer the extrusion pressure when the first pressure bearing section and the second pressure bearing section are under pressure.

[0017] In some embodiments of the present application, the connection strength between the abutting section and the main body wall is less than the connection strength between the first pressure bearing section and the second pressure bearing section, and the time node of changing from fixed connection to sliding connection between the abutting section and the main body wall is earlier than the separation time node between the first pressure bearing section and the second pressure bearing section when the first pressure bearing section and the second pressure bearing section are under pressure.

[0018] In some embodiments of the present application, the abutting section and the first pressure-bearing section extend in opposite directions.

[0019] In some embodiments of the present application, the extension line of the support section and the extension line of the main body wall have a first included angle, and the extension line of the support section and the extension line of the second extension section have a second included angle, the first included angle and the second included angle being mutually staggered angles and mutually complementary.

[0020] In some embodiments of the present application, the battery box girder is a rolled steel girder, and the wall thickness is between 1 mm and 2 mm.

[0021] In a second aspect, embodiments of the present application provide a battery box body, the battery box body comprising a first direction, the battery box body comprising:

[0022] a rolling assembly enclosing a fixing space for fixing a battery cell module, the battery cell module having a tendency to expand in the first direction, the rolling assembly comprising two anti-expansion beams arranged opposite to each other, the two anti-expansion beams being arranged opposite to each other in the first direction, and each of the two anti-expansion beams being the battery box girder as claimed in the first aspect.

[0023] In some embodiments of the present application, the battery box body further comprises a second direction, the first direction and the second direction intersecting, and the rolling assembly further comprising:

[0024] two rolling side girders arranged opposite to each other in the second direction, and each end of each of the anti-expansion beams being connected to two of the rolling side girders to define the fixing space.

[0025] In some embodiments of the present application, each of the two rolling side girders is the battery box girder as claimed in any one of claims 1 to 8, the thickness of the two rolling side girders being the same, and the thickness of the rolling side girders being less than the thickness of the anti-expansion beams.

[0026] In some embodiments of the present application, the rolling assembly further comprises:

[0027] at least one first cross beam and at least one second cross beam, the first cross beam and the second cross beam being located in the fixing space, the first cross beam and the second cross beam being cross-connected, two ends of the first cross beam being respectively welded to two of the rolling side girders, and two ends of the second cross beam being respectively welded to two of the anti-expansion beams.

[0028] In some embodiments of the present application, the battery box further comprises a first frame, two sides of the first frame are connected with one side of the two roll-formed side beams respectively, the first frame is arranged at a distance from the battery box beam close to the first frame to define an anti-extrusion area, and a plurality of anti-extrusion beams are arranged at intervals in the anti-extrusion area, and two ends of each anti-extrusion beam are connected with the first frame and the anti-expansion beam close to the first frame respectively.

[0029] In some embodiments of the present application, the battery box further comprises a second frame, the second frame is arranged opposite to the first frame, two ends of the second frame are connected with the two roll-formed side beams respectively, and the second frame is arranged at a distance from the anti-expansion beam close to the second frame, and the distance is greater than 5mm.

[0030] In a third aspect, embodiments of the present application provide a battery module, comprising:

[0031] a bottom plate;

[0032] a bottom guard plate arranged on the bottom plate;

[0033] a liquid cooling plate arranged on the bottom guard plate;

[0034] a battery box as described in the second aspect arranged on the liquid cooling plate;

[0035] a plurality of battery cell modules arranged in the fixed space of the battery box;

[0036] an integrated busbar arranged on the plurality of battery cell modules;

[0037] an insulating layer arranged on a side of the integrated busbar away from the battery cell modules;

[0038] a box cover arranged on the battery module, and the insulating layer is located between the box cover and the integrated busbar.

[0039] The beneficial effects of embodiments of the present application are as follows:

[0040] In the embodiment of the present application, mainly by utilizing the first pressure bearing section and the second pressure bearing section extending towards each other and partially overlapping, the welding surface is located at the overlapping part, and the extending towards each other makes the welding surface perpendicular to the direction of the extrusion force, effectively avoiding the risk of connection separation of the welding surface due to bearing the extrusion force. And the welding surface is perpendicular, so that the first pressure bearing section and the second pressure bearing section overlap in the direction resisting the extrusion force, enhancing the ability to resist the extrusion. In detail, first of all, by utilizing the main body wall, the first beam wall and the second beam wall to connect and enclose each other to form the structure of the battery box beam, then the first pressure bearing section and the second pressure bearing section are arranged opposite to the main body wall, that is, the first pressure bearing section and the second pressure bearing section are located on the same side of the main body wall, then the first pressure bearing section and the second pressure bearing section extend towards each other and partially overlap, thereby improving the ability of the battery box beam to bear the extrusion force in the direction of the first pressure bearing section towards the main body wall. The overlapping surface of the first pressure bearing section and the second pressure bearing section is the welding surface, which is different from the direction of the welding surface in the related art. The welding surface in the present application is not parallel to the extrusion force, which can effectively reduce the risk of separation of the first pressure bearing section and the second pressure bearing section due to the extrusion force, and the first pressure bearing section and the second pressure bearing section can also improve the strength of bearing the extrusion force due to the overlapping. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0042] Figure 1 is a cross-sectional view of the battery box beam of the related art mentioned in the background;

[0043] Figure 2 is a cross-sectional view of the battery box beam provided by the embodiment of the present application;

[0044] Figure 3 is a three-dimensional structure schematic view of a battery box provided by the embodiment of the present application;

[0045] Figure 4 is Figure 3 is an exploded structure schematic view of

[0046] Figure 5 is a top view structure schematic view of a battery box provided by the embodiment of the present application;

[0047] Figure 6 is Figure 3 is an enlarged structure schematic view of the mounting part in

[0048] Figure 7A three-dimensional structural schematic diagram of a battery module provided by an embodiment of the present application;

[0049] Figure 8 is Figure 7 an explosion structural schematic diagram.

[0050] Legend:

[0051] 1, battery box; 11, roller assembly; 111, roller pressing side beam; 112, anti-expansion beam; 113, first cross beam; 114, second cross beam; 115, fixed space; 12, first side frame; 121, anti-extrusion area; 13, anti-extrusion beam; 14, second side frame; 15, hanging piece; 151, first hanging beam; 152, second hanging beam; 1521, sleeve hole; 153, bushing; 154, anti-rust gasket; 2, bottom plate; 3, bottom guard plate; 4, liquid cooling plate; 5, battery cell module; 6, integrated busbar; 7, main body wall; 8, first beam wall; 81, first pressure bearing section; 811, first extension section; 812, second extension section; 813, first surface; 814, bending section; 82, first connecting section; 83, buffer section; 831, support section; 832, abutting section; 9, second beam wall; 91, second pressure bearing section; 911, second surface; 92, second connecting section. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person skilled in the art without creative work fall within the scope of protection of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, the positional words such as "upper" and "lower" generally refer to the upper and lower in the actual use or working state of the device, and specifically refer to the direction of the drawing surface in the drawings; and "inner" and "outer" refer to the contour of the device.

[0053] Please refer to Figure 1 , the cross-sectional structure of the battery box beam in the related art described in the background art, as can be seen from the figure, the connecting surface of the battery box beam at the right side connection is parallel to the expansion and extrusion force, when the expansion and extrusion force is too large, the connecting surface of the battery box beam at both ends may have the risk of separation.

[0054] For this purpose, please refer to Figure 2 , the embodiments of the present application provide a battery box beam, comprising:

[0055] the main body wall 7;

[0056] The first beam wall 8 is connected to one end of the main body wall 7, and the first beam wall 8 comprises a first bearing segment 81, which is arranged opposite to the main body wall 7;

[0057] The second beam wall 9 is connected to the other end of the main body wall 7, and the second beam wall 9 comprises a second bearing segment 91, which is arranged opposite to the main body wall 7 and extends towards the first bearing segment 81, the second bearing segment 91 and the first bearing segment 81 have an overlapping portion, and the second bearing segment 91 and the first bearing segment 81 are fixedly connected at the overlapping portion.

[0058] The technical scheme provided by the present application mainly utilizes the fact that the first bearing segment 81 and the second bearing segment 91 extend towards each other and partially overlap, so that the welding surface is located at the overlapping portion, and the extension towards each other makes the welding surface perpendicular to the direction of the extrusion force, effectively avoiding the risk of separation of the welding surface due to the bearing of the extrusion force. Moreover, the perpendicular welding surface makes the first bearing segment 81 and the second bearing segment 91 overlap in the direction of resisting the extrusion force, thereby enhancing the ability to resist the extrusion force. In detail, first, the main body wall 7, the first beam wall 8 and the second beam wall 9 are connected to each other to enclose the structure of the battery box beam, then the first bearing segment 81 and the second bearing segment 91 are arranged opposite to the main body wall 7, i.e., the first bearing segment 81 and the second bearing segment 91 are located on the same side of the main body wall 7, and then the first bearing segment 81 and the second bearing segment 91 extend towards each other and partially overlap, thereby improving the ability of the battery box beam to bear the extrusion force in the direction of the first bearing segment 81 towards the main body wall 7. The overlapping surface of the first bearing segment 81 and the second bearing segment 91 is the welding surface, which is different from the direction of the welding surface in the related art. The welding surface in the present application is not parallel to the extrusion force, which can effectively reduce the risk of separation of the first bearing segment 81 and the second bearing segment 91 due to the extrusion force, and the first bearing segment 81 and the second bearing segment 91 can also improve the strength of bearing the extrusion force due to the overlapping.

[0059] In some embodiments, the first pressure receiving section 81 comprises a first extending section 811, a second extending section 812, and a bending section 814, the first extending section 811 and the second extending section 812 are connected through the bending section, the extending directions of the first extending section 811 and the second extending section 812 are the same, the bending section 814 bends from the first extending section 811 towards the main body wall 7, so that the second extending section 812 is closer to the main body wall 7 than the first extending section 811, the first extending section 811 and the second extending section 812 jointly define a connecting portion, the second pressure receiving section 91 is arranged at the connecting portion close to the end of the first pressure receiving section 81, and is welded and fixed with the second extending section 812. The first extending section 811 and the second extending section 812 are circularly arc transitioned, and are integrally bent and formed, which is beneficial to improve the strength of the connecting portion, and the bending transition is more round, avoiding the fracture of the connecting portion caused by the too large bending angle. The second extending section 812 is closer to the main body wall 7 than the first extending section 811, which is equivalent to forming a fault at the first extending section 811 and the second extending section 812, which can be used as a lap joint position of the second pressure receiving section 91 and the first pressure receiving section 81, to provide a lap joint position for the second pressure receiving section 91, avoiding the formation of a more obvious protrusion on one side of the battery box beam due to the overlapping of the first pressure receiving section 81 and the second pressure receiving section 91, which has the risk of damaging the battery cell module 5.

[0060] Further, the first extending section 811 has a first surface 813 away from the main body wall 7, the second pressure receiving section 91 has a second surface 911 away from the main body wall 7, and the first surface 813 and the second surface 911 are coplanar. The coplanar first surface 813 and the second surface 911 can improve the flatness of the side of the battery box beam away from the main body wall 7, avoiding the uneven stress on the battery cell module 5 caused by the protrusion on the side of the battery box beam. Preferably, the bending section 814 has a first length in the vertical direction of the first pressure receiving section 81 towards the main body wall 7, the thickness of the overlapping of the second extending section 812 and the second pressure receiving section 82 in the vertical direction of the first pressure receiving section 81 towards the main body wall 7 is a first thickness, and the first thickness is equal to the first length.

[0061] Further, the two ends of the bending section 814 are circularly arc transitioned with the first extending section 811 and the second extending section 812, respectively. The circular arc transition can effectively avoid the damage of the first pressure receiving section 81 caused by the too large bending angle when bending, and the circular arc transitioned first pressure receiving section 81 has a longer service life than the first pressure receiving section 81 connected by a straight angle.

[0062] In some embodiments, the first beam wall 8 further comprises a first connecting section 82 connected between the first pressure bearing section 81 and the main body wall 7, and the second beam wall 9 further comprises a second connecting section 92 connected between the second pressure bearing section 91 and the main body wall 7, and arranged opposite to the first connecting section 82. The main body wall 7, the first connecting section 82, the first pressure bearing section 81, the second pressure bearing section 91 and the second connecting section 92 enclose a beam cavity. The first beam wall 8, the second beam wall 9 and the main body wall 7 are connected to each other to form a rectangular cross-section of the battery box beam. It should be noted that the connection between the main body wall 7 and the first connecting section 82 and the second connecting section 92 is integrally formed by bending. The connection between the first connecting section 82 and the first pressure bearing section 81 is also integrally formed by bending. The connection between the second connecting section 92 and the second pressure bearing section 91 is also integrally formed by bending. The first pressure bearing section 81 and the second pressure bearing section 91 are overlapped and fixed by welding. In this way, the battery box beam has a hollow structure, and the hole forming process is omitted, thereby reducing the weight of the box beam.

[0063] In some embodiments, the first beam wall 8 further comprises a buffer section 83 connected to the end of the first pressure bearing section 81 close to the second pressure bearing section 91 and extending towards the main body wall 7. The buffer section 83 is configured to slide along the main body wall 7 when the first pressure bearing section 81 and the second pressure bearing section 91 are under pressure, so as to buffer the pressure. The connection between the buffer section 83 and the first pressure bearing section 81 is still integrally formed by bending. The two ends of the buffer section 83 are connected to the main body wall 7 and the first pressure bearing section 81, respectively, which can support the first beam wall 8, the second beam wall 9 and the main body wall 7, and improve the ability of the battery box beam to withstand extrusion pressure. Moreover, the buffer section 83 has a tendency to slide along the main body wall 7, and when the extrusion pressure is too large, the buffer section 83 deforms and slides along the main body wall 7, based on the force of its recovery deformation, which buffers the extrusion pressure and enhances the resistance to extrusion force.

[0064] Further, the buffer section 83 comprises a supporting section 831 and an abutting section 832. The supporting section 831 is connected between the first pressure bearing section 81 and the abutting section 832. The abutting section 832 is parallel to and connected to the main body wall 7, and the connection can be overlapping, abutting and welding, etc. The supporting section 831 supports to enhance the strength of the battery box beam. The abutting section 832 is parallel to and abuts the main body wall 7, which can increase the contact area of the abutting section 832 and the main body wall 7, so as to avoid excessive pressure of the abutting section 832 on the main body wall 7 due to too small contact area. Moreover, when the extrusion pressure is too large, the supporting section 831 transmits the extrusion pressure to the abutting section 832, and the abutting section 832 moves along the main body wall 7 to cause the supporting section 831 to deform and tilt, thereby buffering the extrusion pressure.

[0065] In another embodiment, the abutting section 832 is fixedly connected with the main wall 7, and the abutting section 832 is configured to change from the fixed connection to the sliding connection with the main wall 7 when the first pressure-bearing section 81 and the second pressure-bearing section 82 are under pressure, and slide along the main wall 7 to buffer the extrusion force. In this embodiment, the abutting section 832 is fixedly connected with the main wall 7, such as welding. The fixed connection changes to the sliding connection, which means that when the beam is under excessive extrusion force, the fixed connection between the abutting section 832 and the main wall 7, such as the welding, is torn, resulting in welding failure. At this time, the abutting section 832 can still slide along the main wall 7, thereby further playing a buffering role and forming a secondary protection.

[0066] Further, the connection strength between the abutting section 832 and the main wall 7 is less than the connection strength between the first pressure-bearing section 81 and the second pressure-bearing section 82. When the first pressure-bearing section 81 and the second pressure-bearing section 82 are under pressure, the time node at which the abutting section 832 changes from the fixed connection to the sliding connection with the main wall 7 is earlier than the separation time node between the first pressure-bearing section 81 and the second pressure-bearing section 82. By limiting the connection strength and the time node at which the abutting section 832 changes from the fixed connection to the sliding connection with the main wall 7 is earlier than the separation time node between the first pressure-bearing section 81 and the second pressure-bearing section 82, it can be ensured that when the battery box beam is under a larger extrusion force, the abutting section 832 slides first to play a buffering role, so as to prevent the first pressure-bearing section 81 and the second pressure-bearing section 82 from separating when under extrusion force, thereby preventing damage to the box beam.

[0067] In some embodiments, the abutting section 832 extends reversely to the first pressure-bearing section 81, so that the abutting section 832 is more sensitive to the size of the extrusion force. When under a larger extrusion force, the abutting section 832 can move along the main wall 7 to drive the supporting section 831 to deform, thereby playing a buffering role.

[0068] It should be noted that the battery box beam is made of steel profile, and the specific material is 780DP steel profile, and the production process is rolling process. The wall thickness of the battery box beam is in the range of 1mm to 2mm. Compared with the use of aluminum profile, it is beneficial to reduce the cost and improve the strength.

[0069] In some embodiments, the extension line of the supporting section 831 and the extension line of the main wall 7 have a first included angle, and the extension line of the supporting section 831 and the extension line of the second extending section 812 have a second included angle. The first included angle and the second included angle are mutually staggered angles and mutually complementary. By limiting the included angles to be mutually staggered angles and mutually complementary, the supporting section 831 is inclined in the second direction, which is beneficial to assist the sliding of the abutting section 832, thereby better playing a buffering role.

[0070] Please refer to Figures 2 to 6 The application also provides a battery box 1, which comprises a first direction. The battery box 1 comprises:

[0071] The roller assembly 11 encloses a fixing space 115 for fixing the battery cell module 5, which has a tendency to expand in the first direction, and comprises two anti-expansion beams 112 arranged opposite to each other and spaced apart in the first direction, both of which are the battery box beams as described in the first aspect.

[0072] The battery box 1 uses the anti-expansion beams 112 as described in any of the foregoing embodiments as the anti-expansion beams 112, and uses the structure of the anti-expansion beams 112 to support and buffer the expansion extrusion force, effectively improving the anti-expansion capability of the battery box. The specific beneficial effect derivation process is described in the foregoing embodiments of the battery box beam, which will not be repeated here.

[0073] In some embodiments, the battery box 1 further comprises a second direction intersecting the first direction, and the roller assembly 11 further comprises:

[0074] Two roller side beams 111 arranged opposite to each other in the second direction, and each end of the anti-expansion beam 112 is connected to the two roller side beams 111 to define the fixing space 115.

[0075] Further, referring to Figure 4 and Figure 5 Both of the two roller side beams 111 are the battery box beams as described in any of the foregoing embodiments, and the thickness of the two roller side beams 111 is the same, and the thickness of the roller side beam 111 is less than the thickness of the anti-expansion beam 112. Using the structure of the battery box beam can enhance the ability of the battery box 1 to resist the expansion extrusion force of the battery cell expansion. In addition, limiting the thickness of the roller side beam 111 to be less than the thickness of the anti-expansion beam 112 is mainly based on the main expansion direction of the battery cell, that is, the main expansion direction of the battery cell is the first direction. It should be noted that the thickness refers to the sum of the thickness of the main body wall 7 itself, the thickness of the pressure receiving section arranged opposite to the main body wall 7, and the interval distance between the pressure receiving section and the main body wall 7.

[0076] In some embodiments, the roller assembly 11 further comprises:

[0077] At least one first cross beam 113 and at least one second cross beam 114, both of which are located in the fixing space 115, the first cross beam 113 and the second cross beam 114 are cross-connected, both ends of the first cross beam 113 are connected to the two roller side beams 111, and both ends of the second cross beam 114 are connected to the two anti-expansion beams 112.

[0078] By connecting the two roll edge beams 111 and the two anti-expansion beams 112 to each other, a fixed space 115 is enclosed, which is mainly used for mounting and fixing the battery cell module 5. The fixed space 115 thus enclosed can accommodate a large-size battery cell module 5. In some embodiments, by arranging the first cross beam 113 and the second cross beam 114 in the fixed space 115 and cross-connecting the first cross beam 113 and the second cross beam 114, the fixed space 115 is divided into multiple fixed subspaces, so that multiple battery cell modules 5 can be mounted and fixed in the fixed space 115, and when each battery cell module 5 expands, each expanded battery cell module 5 will be subjected to independent fixed extrusion force to suppress the expansion of each battery cell module 5. In addition, multiple battery cell modules 5 are arranged adjacent to each other and are isolated by cross beams, that is, when the battery cell module 5 is fixedly mounted, the cross beams will be shared, and part of the expansion extrusion force of two adjacent battery cell modules 5 will be offset by acting on the same cross beam, thereby indirectly enhancing the ability of the roll assembly 11 to suppress the expansion of the battery cell module 5.

[0079] It should be noted that the frame structure formed by connecting the roll edge beam 111 and the anti-expansion beam 112 can be rectangular, rhombic or other closed quadrilateral. Similarly, the fixed space 115 can also be rectangular, rhombic or other closed quadrilateral, which is not limited and mainly adjusted according to the structure of the battery cell module 5. Because the common structure of the battery cell module 5 is rectangular, the frame structure and the fixed space 115 in the embodiment are preferably rectangular. As for the first cross beam 113 and the second cross beam 114, one of each is used in the embodiment and cross-connected to divide the fixed space 115 into four fixed subspaces. In other embodiments, two first cross beams 113 and two second cross beams 114 can be used and cross-connected to define more fixed subspaces for placing more battery cell modules 5.

[0080] In addition, the roll edge beam 111, the anti-expansion beam 112, the first cross beam 113 and the second cross beam 114 are all made of roll-processed hollow steel plates with a thickness of 1.0-2.0 mm, thereby meeting the lightweight requirement of the battery module. In addition, the cross section of the roll edge beam 111, the cross section of the first cross beam 113, the cross section of the second cross beam 114 and the cross section of the anti-expansion beam 112 are all in the shape of a sun, thereby improving the ability of each beam to withstand the expansion extrusion force of the battery cell module 5.

[0081] In some embodiments, please refer to Figure 4 and Figure 5The battery box 1 further comprises a first frame 12, two sides of the first frame 12 are connected with one side of the two roll-pressing side beams 111 respectively, the first frame 12 is arranged spaced apart from the anti-expansion beam 112 close to the first frame 12 to define an anti-extrusion area 121, and a plurality of anti-extrusion beams 13 are arranged spaced apart in the anti-extrusion area 121, and two ends of each anti-extrusion beam 13 are connected with the first frame 12 and the anti-expansion beam 112 close to the first frame 12 respectively.

[0082] By using the anti-expansion beam 112 to bear the extrusion pressure of the expansion of the battery cell module 5 instead of the frame, and arranging a plurality of anti-extrusion beams 13 in the anti-extrusion area 121, the effect of inhibiting the expansion of the battery cell module 5 is further improved. In detail, since the battery cell module 5 has a tendency to expand towards the first direction, the scheme proposed in the present application mainly forms the fixed space 115 by using the roll-pressing assembly 11, forms the anti-extrusion area 121 between the first frame 12 and the anti-expansion beam 112, so that the battery cell module 5 is installed in the fixed space 115 and does not directly contact the first frame 12, that is, the extrusion pressure of the expansion of the battery cell module 5 does not directly act on the first frame 12, effectively avoiding the deformation of the first frame 12; and the anti-extrusion beams 13 are arranged in the anti-extrusion area 121, the anti-extrusion beams 13 connect the roll-pressing assembly 11 and the first frame 12, the first frame 12 can not only enhance the strength of the roll-pressing assembly 11 to resist the expansion extrusion pressure to a certain extent, but also can avoid the deformation of the first frame 12 due to directly bearing the expansion extrusion pressure, and the anti-extrusion beams 13 can also enhance the strength of the roll-pressing assembly 11. The buffer section 83 arranged in the anti-expansion beam 112 can also improve the anti-deformation ability of the anti-expansion beam 112 itself, thereby avoiding the transmission of the deformed extrusion pressure to the first frame 12. And the plurality of anti-extrusion beams 13 are arranged spaced apart, compared with directly closely arranging the anti-extrusion beams 13, the anti-expansion beam 112 can to a certain extent avoid the transmission of the deformation to the first frame 12.

[0083] In some embodiments, the battery box 1 further comprises a second frame 14. Two ends of the second frame 14 are connected with the two roll-pressing side beams 111 respectively and are arranged opposite to the first frame 12, and the second frame 14 is arranged spaced apart from the anti-expansion beam 112 close to it, and the distance of the spaced apart arrangement is greater than 5 mm. Because the expansion range of the battery cell module 5 is 1-5 mm, the interval between the second frame 14 and the anti-expansion beam 112 close to it is set to be greater than 5 mm, which can effectively avoid the anti-expansion beam 112 from moving or deforming to affect the second frame 14. Specifically, the two ends of the roll-pressing side beam 111 extend along the second direction and are located outside the two anti-expansion beams 112 respectively, so that when the first frame 12 is connected with the roll-pressing side beam 111, the first frame 12 can form an anti-extrusion area 121 with the anti-expansion beam 112; and when the second frame 14 is connected with the roll-pressing side beam 111, the second frame 14 is arranged spaced apart from the anti-expansion beam 112. By setting the interval between the second frame 14 and the anti-expansion beam 112 to be greater than 5 mm, it can be ensured that when the anti-expansion beam 112 is displaced, the second frame 14 will not be affected by displacement, and the air tightness at the second frame 14 will not be affected.

[0084] It should be noted that for the first frame 12 and the second frame 14, in the present embodiment, they are both sheet metal stamping parts, which can reduce the weight and the cost of opening holes compared with using roll-pressing parts. Because the sheet metal stamping part only needs to use a mold to open a hole, while the roll-pressing part needs to use laser cutting.

[0085] In addition, for the first direction and the second direction, the first direction is the expansion direction of the battery cell module 5, and the first direction intersects with the second direction, preferably, the first direction is perpendicular to the second direction.

[0086] Further, please refer to Figure 2 and Figure 5The roll edge beam 111, the anti-expansion beam 112, the first cross beam 113, and the second cross beam 114 are all hollow steel plate structures with a plate thickness of 1.0-2.0 mm. The roll edge beam 111, the anti-expansion beam 112, the first cross beam 113, and the second cross beam 114 are all formed by bending a steel plate, and the hollow structure formed by bending is a through hole. The buffer section 83 is arranged in the through hole of the roll edge beam 111, the anti-expansion beam 112, the first cross beam 113, and the second cross beam 114. The buffer section 83 arranged in the roll edge beam 111 is integrally formed with the roll edge beam 111 and can be directly bent from a steel plate; the buffer section 83 arranged in the anti-expansion beam 112 is integrally formed with the anti-expansion beam 112 and can be directly bent from a steel plate; the buffer section 83 arranged in the first cross beam 113 is integrally formed with the first cross beam 113 and can be directly bent from a steel plate; and the buffer section 83 arranged in the second cross beam 114 is integrally formed with the second cross beam 114 and can be directly bent from a steel plate. After being bent and formed, the cross sections of the roll edge beam 111, the anti-expansion beam 112, the first cross beam 113, and the second cross beam 114 all have a sun-shaped structure. Compared with a completely hollow beam structure, the beam structure with a sun-shaped cross section has higher strength and can better withstand extrusion force. It should be noted that although the cross sections of the roll edge beam 111 and the cross beams all have a sun-shaped structure, the area of the cross section of the roll edge beam 111 can be different from the area of the cross section of the cross beams to form a size difference, and the size can be selected according to actual needs; and the sun-shaped structure mainly refers to the shape of the cross section being approximately sun-shaped when viewed as a whole, but the cross section shapes of the roll edge beam 111 and the cross beams can be completely the same sun-shaped structure or not completely the same sun-shaped structure, which is not limited.

[0087] Specifically, the plate thickness of the roll edge beam 111 is 1.2-1.5 mm, and in this embodiment, the thickness is preferably 1.3 mm. The plate thickness of the anti-expansion beam 112 is 1.5-2.0 mm, and in this embodiment, the thickness is preferably 1.7 mm. The plate thickness of the first cross beam 113 and the second cross beam 114 is 1.5-2.0 mm, and in this embodiment, the thickness is preferably 1.7 mm. By limiting the plate thickness of the roll edge beam 111, the anti-expansion beam 112, and the cross beams within the above corresponding thickness value range, the strength of the roll edge beam 111 and the cross beams can be ensured, and the difficulty of roll forming can be avoided.

[0088] In some embodiments, referring to Figure 3 and Figure 6The outer side of the roll-formed side beam 111 is provided with a plurality of mounting members 15, and the outer side refers to the side away from the fixed space 115. The plurality of mounting members 15 are arranged at intervals along the second direction, and are used to fix the battery box 1 to other external structures. Compared with directly fixing the roll-formed side beam 111 and the anti-expansion beam 112 to the external structures, the mounting members 15 can isolate the influence of the external structures on the roll-formed side beam 111 and the anti-expansion beam 112 to a certain extent, and protect the internal structures of the battery box 1 from unnecessary mechanical stress and damage.

[0089] Further, the mounting member 15 includes a first mounting beam 151, a second mounting beam 152, and a bushing 153. The first mounting beam 151 is fixed to the outer side of the roll-formed side beam 111, and the side of the first mounting beam 151 away from the roll-formed side beam 111 is embedded in the second mounting beam 152 to fix the second mounting beam 152. Specifically, one side of the second mounting beam 152 is in an open shape, and one side of the first mounting beam 151 is embedded in the second mounting beam 152 through the opening, and the other side of the first mounting beam 151 extends to the outside of the second mounting beam 152 and is welded to the roll-formed side beam 111. The side of the first mounting beam 151 extending into the second mounting beam 152 is arranged at intervals with the inner side of the second mounting beam 152 to define a space for the bushing 153 to pass through. The side of the second mounting beam 152 facing the roll-formed side beam 111 is fixedly connected to the roll-formed side beam 111 in a manner of welding or bonding, and in this embodiment, welding is adopted. The second mounting beam 152 is provided with a sleeve hole 1521, and the bushing 153 is fixed to the second mounting beam 152 through the sleeve hole 1521. The bushing 153 is in interference fit with the sleeve hole 1521.

[0090] Further, referring to Figure 3 and Figure 6 , the mounting member 15 further includes a rust-proof gasket 154, and in some embodiments, the rust-proof gasket 154 is a stainless steel sheet. The rust-proof gasket 154 is fixed to the side of the second mounting beam 152 away from the bushing 153 and is coaxially connected with the sleeve hole 1521. When the bolt passes through the bushing 153, it can pass through the rust-proof gasket 154 coaxially and be connected with the nut on one side of the rust-proof gasket 154. The rust-proof gasket 154 and the second mounting beam 152 are connected and fixed in a manner of welding in this embodiment. When the battery module is installed and locked with the vehicle, and the bolt and the nut are rotated in cooperation, the rust-proof gasket 154 can effectively reduce the wear of the surface of the second mounting beam 152 caused by the nut, and reduce the consumption of the electrophoretic corrosion layer on the surface of the second mounting beam 152. Even if the electrophoretic corrosion layer of the rust-proof gasket 154 is consumed, the surface of the rust-proof gasket 154 made of stainless steel will not rust, which can effectively ensure the corrosion resistance of the battery module.

[0091] Referring to Figure 7 and Figure 8The application also provides a battery module comprising:

[0092] a bottom plate 2;

[0093] a bottom guard plate 3 arranged on the bottom plate 2;

[0094] a liquid cooling plate 4 arranged on the bottom guard plate 3;

[0095] a battery box 1 as any of the preceding embodiments arranged on the liquid cooling plate 4;

[0096] a plurality of cell modules 5 arranged in the fixed space 115 of the battery box 1;

[0097] an integrated busbar 6 arranged on the plurality of cell modules 5;

[0098] an insulating layer arranged on a side of the integrated busbar 6 away from the cell modules 5;

[0099] a box cover arranged on the battery module, and the insulating layer is located between the box cover and the integrated busbar 6.

[0100] It should be noted that, since the battery module comprises the battery box 1 as any of the preceding embodiments, the battery module has the beneficial effects similar to the battery box 1, and the specific beneficial effect derivation process can be found in the embodiments of the battery box 1 part, which will not be repeated here.

[0101] The above has introduced the embodiments of the application in detail, and the principle and implementation mode of the application have been described by applying specific examples; the above embodiment description is only for helping to understand the method of the application and its core idea; meanwhile, for those skilled in the art, according to the idea of the application, the specific implementation mode and application range will have changes; in conclusion, the content of the specification should not be understood as the limitation of the application.

Claims

1. A battery box girder characterized by, The battery box girder is a rolled steel girder, and the battery box girder comprises: a main body wall; a first girder wall connected to one end of the main body wall, the first girder wall comprising a first pressure bearing section, the first pressure bearing section being arranged opposite to the main body wall; a second girder wall connected to the other end of the main body wall, the second girder wall comprising a second pressure bearing section, the second pressure bearing section being arranged opposite to the main body wall and extending towards the first pressure bearing section, the second pressure bearing section and the first pressure bearing section having an overlapping portion, and the second pressure bearing section and the first pressure bearing section being fixedly connected at the overlapping portion; the first girder wall further comprising a buffer section, the buffer section being connected to the end of the first pressure bearing section close to the second pressure bearing section and extending towards the main body wall, the buffer section being configured to support the first pressure bearing section and the second pressure bearing section when the first pressure bearing section and the second pressure bearing section are under pressure.

2. The battery box girder of claim 1, wherein, the first pressure bearing section comprising a first extension section, a second extension section and a bending section, the first extension section and the second extension section being connected by the bending section, and the first extension section and the second extension section having the same extension direction, the bending section being bent from the first extension section towards the main body wall so that the second extension section is closer to the main body wall than the first extension section, the first extension section, the second extension section and the bending section jointly defining a connecting portion, the end of the second pressure bearing section close to the first pressure bearing section being arranged at the connecting portion and being fixedly welded with the second extension section.

3. The battery box girder of claim 2, wherein, the first extension section having a first surface facing away from the main body wall, the second pressure bearing section having a second surface facing away from the main body wall, the first surface being coplanar with the second surface.

4. The battery box girder of claim 2, wherein, the two ends of the bending section being circularly arc transitioned with the first extension section and the second extension section respectively.

5. The battery box girder of claim 1, wherein, the first girder wall further comprising a first connecting section connected between the first pressure bearing section and the main body wall, the second girder wall further comprising a second connecting section connected between the second pressure bearing section and the main body wall and arranged opposite to the first connecting section, the main body wall, the first connecting section, the first pressure bearing section, the second pressure bearing section and the second connecting section enclosing a girder inner cavity.

6. The battery box girder of claim 2, wherein, the buffer section comprising a support section and an abutting section, the support section being connected between the first pressure bearing section and the abutting section, and the abutting section being parallel to and connected with the main body wall.

7. The battery box girder of claim 6, wherein, the abutting section abutting with the main body wall, the abutting section being configured to slide along the main body wall to buffer the extrusion force when the first pressure bearing section and the second pressure bearing section are under pressure.

8. The battery box girder of claim 6, wherein, the abutting section being fixedly connected with the main body wall, the abutting section being configured to change from fixed connection to sliding connection with the main body wall and slide along the main body wall to buffer the extrusion force when the first pressure bearing section and the second pressure bearing section are under pressure.

9. The battery box girder of claim 8, wherein, The connection strength between the abutting section and the main body wall is less than the connection strength between the first pressure-bearing section and the second pressure-bearing section, and the time node of the connection between the abutting section and the main body wall changing from fixed connection to sliding connection is earlier than the separation time node between the first pressure-bearing section and the second pressure-bearing section when the first pressure-bearing section and the second pressure-bearing section are under pressure.

10. The battery box girder of claim 6, wherein, The abutting section and the first pressure-bearing section extend in opposite directions.

11. The battery box girder of claim 6, wherein, The extension line of the support section and the extension line of the main body wall have a first included angle, and the extension line of the support section and the extension line of the second extension section have a second included angle, the first included angle and the second included angle are staggered angles and are mutually exclusive.

12. The battery box girder of claim 1, wherein, The wall thickness of the battery box girder is between 1mm and 2mm.

13. A battery pack, characterized by The battery box body includes a first direction, and the battery box body includes: A roller assembly surrounds a fixed space for fixing a battery cell module, the battery cell module has a tendency to expand in the first direction, the roller assembly includes two oppositely arranged anti-expansion beams, the two anti-expansion beams are oppositely arranged along the first direction, and the two anti-expansion beams are the battery box girders according to any one of claims 1 to 12.

14. The battery pack of claim 13, wherein, The battery box body further includes a second direction, the first direction and the second direction intersect, and the roller assembly further includes: Two roller edge girders are oppositely arranged along the second direction, and the two ends of each anti-expansion beam are connected to the two roller edge girders to define the fixed space.

15. The battery pack of claim 14, wherein, The two roller edge girders are the battery box girders, the thicknesses of the two roller edge girders are the same, and the thickness of the roller edge girder is less than the thickness of the anti-expansion beam.

16. The battery pack of claim 14, wherein, The roller assembly further includes: At least one first cross beam and at least one second cross beam, the first cross beam and the second cross beam are located in the fixed space, the first cross beam and the second cross beam are cross-connected, the two ends of the first cross beam are respectively welded to the two roller edge girders, and the two ends of the second cross beam are respectively welded to the two anti-expansion beams.

17. The battery pack of claim 14, wherein, The battery box body further includes a first frame, two sides of the first frame are respectively connected to one side of the two roller edge girders, the first frame is spaced apart from the battery box girder close to the first frame to define an anti-extrusion area, and a plurality of anti-extrusion beams are spaced apart in the anti-extrusion area. The two ends of each anti-extrusion beam are respectively connected to the first frame and the anti-expansion beam close to the first frame.

18. The battery pack of claim 17, wherein, The battery box body further includes a second frame, the second frame is oppositely arranged with the first frame, the two ends of the second frame are respectively connected to the two roller edge girders, and the second frame is spaced apart from the anti-expansion beam close to the second frame. The distance of the spaced apart is greater than 5mm.

19. A battery module, comprising: It includes: A bottom plate; A bottom guard plate is arranged on the bottom plate; A liquid cooling plate is arranged on the bottom guard plate; The battery box body according to any one of claims 13 to 18 is arranged on the liquid cooling plate; A plurality of battery cell modules are arranged in the fixed space of the battery box body; An integrated busbar is arranged on the plurality of battery cell modules; An insulating layer is arranged on the side of the integrated busbar away from the battery cell modules; A box cover is arranged on the battery module, and the insulation layer is arranged between the box cover and the integrated busbar.

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