Battery Box

Abstract

A battery box is disclosed, comprising: a box bottom plate; and a box frame, which is located around the box bottom plate and cooperates with the box bottom plate to form a space for accommodating batteries, wherein the box frame is embedded in the box bottom plate at the connection between the box frame and the box bottom plate. The battery box is made of aluminum alloy using an extrusion process, and the box bottom plate and the box frame are both designed as a hollow structure. Through embedded connection, the welding process and the use of solder are reduced, and the weight of the battery box is effectively reduced, the structural strength of the battery box is improved, the energy density and anti-corrosion performance of the power battery are improved, and the driving mileage of new energy vehicles is improved.

Description

Technical Field

[0001] The present invention relates to the field of power batteries, and more specifically to a battery box. Background Art

[0002] Batteries have the characteristics of high power, long life, no pollution, safety, reliability, and lightness. With the vigorous promotion of new energy vehicles and convenient mobile terminals, batteries have entered a golden period of development and the industry is developing rapidly.

[0003] Taking cars as an example, the batteries in cars can be roughly divided into two categories: starting batteries and power batteries. Starting batteries are used to start the car engine, while power batteries are the main source of power for the car. In order to increase the range of new energy vehicles, it is usually necessary to arrange a large number of power batteries that occupy a larger space on new energy vehicles. Since battery integration is used, in order to achieve the integration of a large number of batteries, the batteries must be installed in the battery box. Currently, the power battery box used is made of sheet metal.

[0004] Although the sheet metal box can meet the design standard requirements, it is too heavy, which affects the energy density of the battery pack and has a certain impact on the mileage of the electric vehicle. In addition, the sheet metal box is made of steel structures, and the sheet metal bending parts are prone to tearing, and the corrosion resistance is also poor. The existing cast aluminum battery box is prone to defects such as pores and pinholes during the production process due to casting defects and other reasons, which will have a great impact on the strength of the battery box. In addition, the existing battery box has corresponding ribs inside to fix the batteries, which increases the weight of the battery box. Summary of the invention

[0005] In view of this, the present invention provides a battery box, which is manufactured using aluminum alloy through an extrusion process. The box bottom plate and the box frame are designed to be hollow structures. Through embedded connection, the welding process and the use of solder are reduced, and the weight of the battery box is effectively reduced. The structural strength of the battery box is increased, the energy density and corrosion resistance of the power battery are improved, and the mileage of new energy vehicles is increased.

[0006] According to the present invention, a battery box is provided, comprising: a box bottom plate; and a box frame, which is located around the box bottom plate and cooperates with the box bottom plate to form a space for accommodating batteries, wherein the box frame is embedded in the box bottom plate at the connection between the box frame and the box bottom plate.

[0007] Preferably, the box bottom plate is a double-layer sealing structure, and a cavity is formed between the first layer and the second layer of the box bottom plate.

[0008] Preferably, the first layer and the second layer of the box bottom plate are connected by a plurality of connecting ribs, and the connecting ribs are connected head to tail, so as to isolate the cavity into a plurality of independent sealed cavities.

[0009] Preferably, in the battery box, the rivet nut passes through the first layer of the box bottom plate, enters the cavity, and is fixed on the first layer of the box bottom plate.

[0010] Preferably, the rivet nut has its own limiting height and is assembled with the battery module on the bottom plate of the box body by screws.

[0011] Preferably, the box frame includes: side walls, which are located around the box bottom plate and are arranged at an angle to the box bottom plate; pins, which are located at the first end of the side walls and form an embedded connection with the cavity of the box bottom plate; and flanges, which are located at the second end of the side walls, and the extension direction of the flanges is opposite to the extension direction of the pins.

[0012] Preferably, the box frame is a hollow structure, the interior of which is connected by connecting ribs, the connecting ribs are arranged in an inclined manner, and the flange is connected to the side wall by a plurality of inclined connecting ribs.

[0013] Preferably, the box frame is formed by splicing four independent hollow material plates, and each of the hollow material plates includes the side wall and the pin.

[0014] Preferably, forward and reverse friction stir welding is performed at the connection between the box bottom plate and the box frame, and cold metal transition welding is performed at the box frame.

[0015] Preferably, the box bottom plate comprises a plurality of mutually spliced ​​hollow extruded profile plates, wherein the plurality of profile plates are horizontally butted and welded together by friction stir welding and then machined.

[0016] Preferably, the box bottom plate and the box frame are both aluminum alloy extruded cavity structures.

[0017] The battery box provided by the present invention is manufactured using aluminum alloy through an extrusion process. The box bottom plate and the box frame are designed to be hollow structures. The welding process and the use of solder are reduced through embedded connection, and the connection is tight, which also effectively reduces the weight of the battery box, improves the energy density and corrosion resistance of the power battery, and increases the mileage of new energy vehicles.

[0018] The bottom plate of the battery box and the inside of the box frame are connected by connecting ribs, which can effectively improve the strength of the battery box and improve the energy density and corrosion resistance of the power battery.

[0019] Providing rivet nuts on the bottom plate of the battery box can reduce the thickness of the bottom plate of the box, reduce the weight of the battery box, increase the energy density of the power battery, and improve the endurance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings.

[0021] Figure 1 A schematic diagram of the overall structure of a battery box according to an embodiment of the present invention is shown.

[0022] Figure 2 A schematic structural diagram of a box bottom plate of a battery box according to an embodiment of the present invention is shown.

[0023] Figure 3 A schematic diagram showing the connection between the rivet nut and the bottom plate of the battery box according to an embodiment of the present invention is shown.

[0024] Figure 4 A schematic structural diagram of a box frame of a battery box according to an embodiment of the present invention is shown.

[0025] Figure 5 A schematic cross-sectional view of a box frame of a battery box according to an embodiment of the present invention is shown.

[0026] Figure 6 A schematic diagram showing a battery box frame embedded in a box bottom plate according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] Various embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. In various drawings, the same elements are represented by the same or similar reference numerals.

[0028] Figure 1 A schematic diagram of the overall structure of a battery box according to an embodiment of the present invention is shown.

[0029] Figure 2 A schematic structural diagram of a box bottom plate of a battery box according to an embodiment of the present invention is shown.

[0030] like Figure 1 and Figure 2 As shown, the battery box 100 of the embodiment of the present invention mainly includes a box bottom plate 110 and a box frame 120. The box frame 120 is located around the box bottom plate 110 and cooperates with the box bottom plate 110 to form a space for accommodating batteries. At the connection between the box frame 120 and the box bottom plate 110, the box frame 120 is embedded in the box bottom plate 110. The battery box 100 of the embodiment of the present invention also includes an upper cover (not shown in the figure), which is arranged on the box frame 120 and the box bottom plate 110.

[0031] The box bottom plate 110 and the box frame 120 are both aluminum alloy extruded cavity structures, which are made of aluminum alloy through an extrusion process to reduce defects such as pores and pinholes, reduce the weight of the battery box 100, and enhance the strength.

[0032] Furthermore, the box bottom plate 110 of the battery box 100 includes a plurality of mutually spliced ​​hollow extruded profile plates, for example, 5 aluminum alloy hollow extruded profile plates 111 are horizontally spliced ​​together, and then the joints are welded together by friction stir welding FSW, and then machined to smooth the surface of the box bottom plate 110, wherein the five plates 111 are a module mounting structural beam and a bottom plate integrally extruded structure. The box weight of the aluminum alloy hollow profile of this structure is much lower than that of the steel material box, which greatly reduces the weight of the battery box and improves the energy density of the battery box.

[0033] Some reinforcing ribs 140 are also provided on the surface of the box bottom plate 110 for dividing chambers and the like.

[0034] Figure 3 A schematic diagram showing the connection between the rivet nut and the bottom plate of the battery box according to an embodiment of the present invention is shown.

[0035] like Figure 3 As shown, the box bottom plate 110 is a double-layer sealed structure, and a sealed cavity 114 is formed between the upper plate 112 and the lower plate 113 of the box bottom plate 110. There are gaps around the cavity 114 of the box bottom plate 110, which are used to accommodate the box frame 120 and form an embedded connection with the box frame 120. In order to make the box bottom plate 110 more solid, for example, a plurality of connecting ribs 115 can be set between the upper plate 112 and the lower plate 113 of the box bottom plate 110, and the connecting ribs 115 are connected end to end to isolate the cavity 114 into a plurality of independent sealed cavities. For example, the connecting ribs 115 arranged obliquely divide the cavity 114 into a plurality of triangular areas, or the connecting ribs 115 arranged vertically to the box bottom plate 110 divide the cavity 114 into a plurality of identical or different cavities. The cavity surrounded by the cavity structure is filled with connecting ribs 115, which play a supporting and reinforcing role, and can reduce weight while ensuring strength.

[0036] Combination Figure 1 and Figure 2The battery box 100 of the embodiment of the present invention further includes a rivet nut 130. In order to reduce the weight of the battery box 100, the thickness of the bottom plate 110 of the box body is set to be relatively small, so it is not easy to assemble with other components, and a rivet nut can be used. The bottom plate 110 of the box body is provided with a plurality of blind holes, that is, a plurality of holes that penetrate the upper plate 112 but not the lower plate 113. The rivet nut 130 is riveted in the blind holes. The rivet nut 130 passes through the upper plate 112 of the bottom plate 110 of the box body, enters the cavity 114, and is fixed on the upper plate 112. A boss is formed on the outer surface of the upper plate 112 of the bottom plate 110 of the box body, and the height of the rivet nut 130 inside the cavity 114 is less than the thickness of the cavity 114.

[0037] Preferably, a plurality of rows of rivet nuts 130 are provided on each aluminum alloy hollow extruded profile plate 111 . For example, the rivet nuts 130 are grouped into two or four each, and a plurality of groups are provided on each plate 111 .

[0038] The rivet nut 130 of this embodiment adopts a blind hole M6 rivet nut with a built-in limiting height, for example, a height of 5 mm, and is assembled with the battery module on the box bottom plate 110 by screws. Through the rivet nut 130, the battery box 100 can be directly assembled with the module, with a simple structure, firm riveting, high efficiency, and can reduce the thickness of the profile reserved plate to a limited extent, reduce weight, and has good sealing performance.

[0039] Figure 4 A schematic structural diagram of a box frame of a battery box according to an embodiment of the present invention is shown. Figure 5 A schematic cross-sectional view of a box frame of a battery box according to an embodiment of the present invention is shown. Figure 5 yes Figure 4 A cross-sectional view taken along line AA'.

[0040] like Figure 4 and Figure 5 As shown, the box frame 120 includes: side walls 121, pins 122 and flanges 123. The side walls 121 are located around the box bottom plate 110 and are set at an angle to the box bottom plate 110, for example, they are set vertically around the box bottom plate 110, or they are at a 45° angle to the box bottom plate 110; the pins 122 are located at one end of the side walls 121 and form an embedded connection with the cavity 114 of the box bottom plate 110, and the pins 122 are inserted into the gaps reserved around the cavity 114 of the box bottom plate 110; the flanges 123 are located at the other end of the side walls 121, and the extension direction of the flanges 123 is opposite to the extension direction of the pins 122. For example, the pins 122 are inserted into the inside of the box bottom plate 110 to form an embedded connection, so if the side walls 121 are set at an angle to the box bottom plate 110, then the side walls 121 and the pins 122 are also connected at an angle.

[0041] Preferably, the box frame 120 is a hollow structure, the interior of which is connected by connecting ribs 124, the connecting ribs 124 can be arranged in an inclined manner, and the flange 123 is connected to the side wall 121 by a plurality of inclined connecting ribs 124. The weight of the battery box 100 is reduced while maintaining the strength and toughness of the battery box 100.

[0042] The box frame 120 is, for example, formed by splicing four independent hollow material plates, each of which includes a side wall 121 and a pin 122, which are respectively connected to the box bottom plate 110 in an embedded manner. A connecting portion 125 can also be provided between each hollow material plate to smooth the connection. The box frame 120 is formed by splicing four parts of aluminum alloy extruded cavity profile plates, and each part is welded by stir friction welding (FSW). There are many auxiliary mounting holes on it, and nuts 126 are riveted on the auxiliary mounting holes. The combination of the auxiliary mounting holes and the nuts 126 effectively strengthens the overall installation strength. The flange 123 is, for example, a die-cast aluminum structural beam, and there are connecting ribs inside the beam to ensure the strength of the box and reduce the weight. A through hole is left on the flange 123, which is convenient for the battery box to be fixed with other parts by threaded fixing. The internal connecting ribs 124 of the box frame 120 are arranged in an inclined manner, and this arrangement of the connecting ribs 124 is higher in strength than other arrangements.

[0043] The box frame 120 and the internal connecting ribs 124 are formed by extrusion, which not only reduces the amount of welding between the plates, improves production efficiency, but also reduces the weight of the box while ensuring strength. The side wall 121 and the flange 123 are connected by the connecting ribs 124 and integrally die-casted, and this structure can effectively avoid failure of the flange 123 due to insufficient connection strength.

[0044] Figure 6 A schematic diagram showing a battery box frame embedded in a box bottom plate according to an embodiment of the present invention. Figure 6 yes Figure 1 A cross-sectional view formed by cutting along BB'.

[0045] like Figure 6 As shown, combined Figure 1-Figure 5 The pins 122 of the box frame 120 of the battery box 110 of the embodiment of the present invention are horizontally embedded in the cavity 114 of the box bottom plate 110, and the upper plate 112 and the lower plate 113 of the box bottom plate 110 clamp the pins 122 to form a tight connection. Nuts 126 are provided on the side wall 121 to facilitate installation with other components.

[0046] Preferably, after embedding, the embedded connection parts of the box bottom plate 110 and the box frame 120 are spot welded and fixed, and then the positive and negative friction stir welding (FSW) is performed at the connection, and then cold metal transition welding (CMT) is performed at the box frame 120. The friction stir welding (FSW) welding has excellent sealing performance, and the strength of the heat affected zone after welding is high, which ensures the product yield. After welding is completed, the rivet nut 130 and the wire sleeve are installed, and then the air pressure is tested at the box bottom plate 110 to ensure the overall airtightness of the box and improve the production yield of the battery box 100.

[0047] The aluminum alloy die-casting battery box provided by the present invention has higher strength than a cast aluminum battery box and higher energy density than a steel structure battery box. The battery box frame and the bottom plate are both extruded cavity structures and are connected in an embedded manner. The structure has good sealing performance, reliable strength, and saves materials.

[0048] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0049] Finally, it should be noted that: according to the embodiments of the present invention as described above, these embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, according to the above description, many modifications and changes can be made. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention. This specification selects and specifically describes this embodiment in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and the modified use based on the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A battery box, comprising: Box bottom plate; as well as The box frame is located around the box bottom plate and cooperates with the box bottom plate to form a space for accommodating batteries. Wherein, at the connection between the box frame and the box bottom plate, the box frame is embedded in the box bottom plate, the box bottom plate is a double-layer sealing structure, and a cavity is formed between the first layer and the second layer of the box bottom plate for accommodating the box frame. The box frame includes: Side walls are located around the bottom plate of the box body and are arranged at an angle to the bottom plate of the box body; A pin, located at a first end of the side wall, forms an embedded connection with the cavity of the bottom plate of the box body, and the pin is horizontally embedded in the cavity of the bottom plate; and A flange is located at the second end of the side wall, and the extending direction of the flange is opposite to the extending direction of the pin. The first layer and the second layer of the box bottom plate are connected by a plurality of connecting ribs, and the connecting ribs are connected end to end to isolate the cavity into a plurality of independent sealed cavities.

2. The battery box according to claim 1, wherein: Also includes: The rivet nut passes through the first layer of the box bottom plate, enters the cavity, and is fixed on the first layer of the box bottom plate.

3. The battery box according to claim 2, wherein: The rivet nut has its own limiting height and is assembled with the battery module on the bottom plate of the box body through screws.

4. The battery box according to claim 1, wherein: The box frame is a hollow structure, the interior of which is connected by connecting ribs, the connecting ribs are arranged in an inclined manner, and the flange is connected to the side wall by a plurality of inclined connecting ribs.

5. The battery box according to claim 1, wherein: The box frame is formed by splicing four independent hollow material plates, and each of the hollow material plates includes the side wall and the pins.

6. The battery box according to claim 1, wherein: Positive and negative stir friction welding is performed at the connection between the box bottom plate and the box frame, and cold metal transition welding is performed at the box frame.

7. The battery box according to claim 1, wherein: The box bottom plate includes a plurality of mutually spliced ​​hollow extruded profile plates, wherein the plurality of profile plates are horizontally butted and welded together by friction stir welding and then machined.

8. The battery box according to claim 1, wherein: The box bottom plate and the box frame are both aluminum alloy extruded cavity structures.

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