Power battery pack, vehicle and assembly method of power battery pack

Abstract

The invention discloses a power battery pack which comprises a box body assembly and a module assembly, the box body assembly is of an integrated structure which is integrally formed in a die-casting mode and internally hollow, the module assembly is located in an inner cavity of the box body assembly, and a bottom protection plate is arranged at the bottom of the box body assembly. The power battery pack and the box body assembly are of an integrally formed structure, an upper cover and a sealing gasket do not need to be arranged, the system weight is reduced, the production efficiency is improved, and the box body material cost is reduced; and the module assembly and the BDU adopt an inverted design, so that the disassembly and assembly are convenient, and the maintenance is convenient. The invention further discloses a vehicle and an assembling method of the power battery pack.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile power battery systems, and in particular, the present invention relates to a power battery pack, a vehicle, and an assembly method of the power battery pack. Background Art

[0002] At present, the box assembly of the power battery pack is composed of an upper cover, a sealing gasket and a lower box. The lower box is made of extruded aluminum profiles through cutting, welding, riveting and other processes. The production process is complex, the cost is high and the molding efficiency is low.

[0003] The upper cover of the box assembly is made of carbon steel drawing die or composite material. A sealing gasket is added between the upper cover and the lower box. The upper cover is located above the lower box. There may be a problem of sealing failure during use. Later maintenance requires the entire power battery pack to be disassembled, which is inconvenient.

[0004] It is hoped to provide an improved power battery case assembly, particularly to improve the structure of the power battery case assembly and increase the production efficiency of the power battery case assembly. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a power battery pack, the purpose of which is to optimize the structure and facilitate production and maintenance.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a power battery pack, including a box assembly and a module assembly, the box assembly is an integrated structure that is die-cast and hollow inside, the module assembly is located in the inner cavity of the box assembly, and a bottom guard plate is arranged at the bottom of the box assembly.

[0007] The box assembly includes a top wall and a plurality of side walls arranged on the top wall and extending toward the bottom of the top wall, the bottom guard plate is located below the side wall and connected to the side wall, and the module assembly is located between the top wall and the bottom guard plate.

[0008] A fixing device is arranged in the inner cavity of the box assembly, and the module assembly is mounted on the fixing device by a first bolt. The first bolt passes through the module assembly from below and is inserted into a first mounting hole on the fixing device.

[0009] The fixing device is provided with a first nut matched with the first bolt, and the first nut is located between the fixing device and the top wall.

[0010] A high-voltage distribution module is arranged in the inner cavity of the box assembly, and the high-voltage distribution module is mounted on the fixing device by a second bolt, and the second bolt passes through the high-voltage distribution module from the bottom and is inserted into the second mounting hole on the fixing device.

[0011] The fixing device is provided with a second nut matched with the second bolt, and the second nut is located between the fixing device and the top wall.

[0012] The fixing device comprises a longitudinal beam, a plurality of longitudinal beams are provided, and the longitudinal beams are fixedly connected to the box assembly.

[0013] A protective coating is provided on the bottom surface of the bottom guard plate.

[0014] The present invention also provides a vehicle, comprising the power battery pack.

[0015] The present invention also provides a method for assembling a power battery pack, comprising the steps of:

[0016] S1, installing the box assembly;

[0017] S2, installing the module assembly into the box assembly from the bottom of the box assembly;

[0018] S3. Install the bottom guard plate at the bottom of the box assembly.

[0019] The power battery pack of the present invention has a box assembly that is an integrated structure, and does not require an upper cover and a sealing gasket, thereby reducing system weight, improving production efficiency, and reducing box material costs; the module assembly and BDU are inverted in design, which is easy to disassemble and assemble, and convenient for maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of a power battery pack of the present invention;

[0021] Figure 2 is a top view of the power battery pack of the present invention;

[0022] Figure 3 is an exploded schematic diagram of the power battery pack of the present invention;

[0023] Figure 4 This is a view of the inverted installation of the modules inside the battery system;

[0024] Figure 5 It is the block diagram of the power battery system;

[0025] The markings in the above figures are: 1. Box assembly; 2. Front adapter bracket; 3. Longitudinal beam; 4. Rear adapter bracket; 5. High-voltage distribution module (BDU) and power battery management system (BMS); 6. Module assembly; 7. Bottom guard plate; 8. Cooling water inlet; 9. Cooling water outlet; 10. First bolt; 11. Second bolt; 12. First nut; 13. Protective coating. DETAILED DESCRIPTION

[0026] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0027] It should be noted that when an element is referred to as being "fixed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower" and similar expressions used in this article are for illustrative purposes only.

[0028] It should be noted that, in the following embodiments, the “first”, “second” and “third” mentioned do not represent an absolute distinction in structure and / or function, nor do they represent a sequence of execution, but are merely for the convenience of description.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly connected by technicians in the technical field to which the present invention belongs. The terminology used in the specification of the present invention is for the purpose of describing specific embodiments and is not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0030] like Figures 1 to 4 As shown, the present invention provides a power battery pack, including a power battery management system (BMS), a box assembly 1 and a module assembly 6. The box assembly 1 is an integrated structure that is die-cast and hollow inside. The module assembly 6 is located in the inner cavity of the box assembly 1, and a bottom guard plate 7 is arranged at the bottom of the box assembly 1.

[0031] Specifically, the present invention is a design method for a new energy vehicle power battery system without a top cover and a sealing gasket. The battery box adopts an integrated die-casting design and an inverted design and installation method inside the battery pack; in order to reduce the cost of the new energy vehicle power battery system and reduce the number of parts, a large number of complex connection and sealing processes are also avoided; from the efficiency point of view, the reduction in the number of parts and welding processes improves production efficiency, and is also beneficial to the after-sales maintenance of the battery pack in the later stage. During maintenance, it is only necessary to disassemble and assemble the bottom guard plate 7, and there is no need to disassemble the entire battery pack system; a battery system is specially designed for use in new energy vehicles, and the box body is sealed into a box assembly 1 by an integrated die-casting molding and a carbon steel drawing die molding of the bottom guard plate 7, without a top cover and a sealing gasket; the internal module and the high-voltage distribution module are invertedly installed on the battery box body, and the entire battery system is then invertedly installed on the vehicle body by a lift.

[0032] Compared with the existing battery system design for new energy vehicle models, the present invention reduces the upper cover and sealing gasket components, and uses one-piece die-casting for the box body, which reduces the weight of the box body, improves production efficiency, and reduces material costs; the internal modules of the battery system and the high-voltage distribution module are inverted and installed, and the module adopts large-surface liquid cooling, which increases the cooling area and thermal runaway exhaust channel, greatly reducing thermal runaway.

[0033] like Figures 1 to 3 As shown, the box assembly 1 includes a top wall and a plurality of side walls arranged on the top wall and extending toward the bottom of the top wall, the bottom guard plate 7 is located below the side wall and connected to the side wall, the module assembly 6 is located between the top wall and the bottom guard plate 7, and the bottom guard plate 7 is used to close the bottom opening of the module assembly 6.

[0034] like Figures 1 to 3 As shown, the box assembly 1 is a rectangular shell structure. The material of the box assembly 1 is aluminum alloy. Four side walls are set. The four side walls are fixedly connected to the four sides of the top wall respectively. The top wall is set horizontally, and the side walls are set vertically. The four side walls are arranged opposite to each other in pairs. The top wall and the side walls are formed in one piece. The bottom guard plate 7 is parallel to the top wall, and the two are arranged oppositely. The top wall makes the top of the box assembly 1 in a closed state. After the bottom guard plate 7 is fixedly installed with the box assembly 1, the bottom of the box assembly 1 is in a closed state.

[0035] The box assembly 1 adopts integrated die-casting technology. The advantages of integrated die-casting battery box are: the welding process of aluminum profiles is long and inefficient, while integrated die-casting can be quickly formed and more efficient; the weld quality problem of profile welding can be better solved by integrated die-casting. From the perspective of production cost, there is no need to invest in equipment for a variety of aluminum profiles, only one die-casting equipment is needed, and the overall process production process is simplified. In the future, with the improvement of the performance of various types of alloy materials and the increase in the production capacity of large-scale die-casting machines, high-energy battery packs for pure electric vehicles are also expected to be integrated die-cast.

[0036] like Figure 3 and Figure 4As shown, a fixing device is provided in the inner cavity of the box assembly 1, and the module assembly 6 is installed on the fixing device by a first bolt 10. The first bolt 10 passes through the module assembly 6 from the bottom of the module assembly 6 and is inserted into the first mounting hole on the fixing device. A first nut 12 matching with the first bolt 10 is provided on the fixing device, and the first nut 12 is located between the fixing device and the top wall. The first nut 12 is fixed to the fixing device by welding, and the first bolt 10 is vertically arranged, and the first bolt 10 and the first nut 12 are threadedly connected. A plurality of first bolts 10 are provided, and the number of first nuts 12 is the same as the number of first bolts 10, and each first bolt 10 is matched with a first nut 12 respectively. The first bolt 10 is a hexagonal head bolt, and the first bolt 10 includes a screw portion and a hexagonal head portion, and the screw portion is provided with an external thread, and the screw portion is threadedly connected with the first nut 12, and the screw portion passes through the through hole on the module assembly 6 and is inserted into the first mounting hole, and the first nut 12 is located above the first mounting hole, and the hexagonal head portion is located below the module assembly 6. During assembly, the module assembly 6 can be installed into the inner cavity of the box assembly 1 from the bottom of the box assembly 1, and the first bolt 10 is inserted into the through hole of the module assembly 6 from the bottom of the module assembly 6, and then inserted into the first mounting hole, and finally tightened with the first nut 12 to achieve fixed installation of the module assembly 6.

[0037] like Figure 3 and Figure 4 As shown, a high-voltage power distribution module is arranged in the inner cavity of the box assembly 1, and the high-voltage power distribution module is installed on the fixing device through a second bolt 11. The second bolt 11 is inserted into the second mounting hole on the fixing device after passing through the high-voltage power distribution module from the bottom of the high-voltage power distribution module. A second nut matching with the second bolt 11 is arranged on the fixing device, and the second nut is located between the fixing device and the top wall. The second nut is fixed to the fixing device by welding, and the second bolt 11 is arranged vertically, and the second bolt 11 is threadedly connected with the second nut. A plurality of second bolts 11 are arranged, and the number of second nuts is the same as the number of second bolts 11, and each second bolt 11 is matched with a second nut respectively. The second bolt 11 is a hexagonal head bolt, and the second bolt 11 includes a screw portion and a hexagonal head portion, and the screw portion is provided with an external thread, and the screw portion is threadedly connected with the second nut, and the screw portion passes through the through hole on the high-voltage power distribution module and is inserted into the second mounting hole, and the second nut is located above the second mounting hole, and the hexagonal head portion is located below the high-voltage power distribution module. During assembly, the high-voltage distribution module can be installed into the inner cavity of the box assembly 1 from the bottom of the box assembly 1, and the second bolt 11 is inserted into the through hole of the high-voltage distribution module from the bottom of the high-voltage distribution module, and then inserted into the second mounting hole, and finally tightened with the second nut to achieve fixed installation of the high-voltage distribution module.

[0038] like Figure 3As shown, the fixing device mainly includes a longitudinal beam 3 , a plurality of longitudinal beams 3 are provided, the longitudinal beam 3 is fixedly connected to the box assembly 1 , and the first nut 12 and the second nut are fixedly connected to the longitudinal beam 3 .

[0039] The power battery system adopts an inverted design to install the module assembly 6 and the high-voltage distribution module invertedly on the box assembly 1 through the longitudinal beam 3, which is convenient for later maintenance. In addition, the locking direction Z of the tabs of the module assembly 6 and the high-voltage distribution module is consistent with the ground direction.

[0040] like Figure 3 and Figure 4 As shown, a protective coating 13 is provided on the bottom surface of the bottom guard plate 7. In this embodiment, the guide plate is made of carbon steel, and the material of the protective coating 13 is PVC (polyvinyl chloride). By providing the protective coating 13 at the bottom of the battery pack, the protective performance of the battery pack can be enhanced, making it more wear-resistant and corrosion-resistant, thereby protecting the battery pack from damage by the external environment and ensuring that the battery pack can remain in good condition in unexpected situations such as collisions.

[0041] like Figure 1 and Figure 2 As shown, a front adapter bracket 2 and a rear adapter bracket 4 are respectively provided at both ends of the box assembly 1, the two front adapter brackets 2 are fixedly mounted on one end of the box assembly 1, and the two rear adapter brackets 4 are fixedly mounted on the other end of the box assembly 1, and the power battery pack is fixedly mounted on the vehicle body through the front adapter bracket 2 and the rear adapter bracket 4.

[0042] The power battery pack of the above structure is mainly composed of a box assembly 1, various metal brackets, longitudinal beams 3, bottom guard plates 7 and bolts, etc. It is the "skeleton" of the power battery pack; it plays a role in supporting, resisting mechanical shock and mechanical vibration. The electrical system of the power battery pack: It consists of a high-voltage jumper or a high-voltage wiring harness, a low-voltage wiring harness and a relay. The thermal management system includes a liquid cooling plate and a cooling water pipe.

[0043] The power battery management system of the power battery pack is composed of sensors, actuators, controllers (electronic control units) and other components, which collect system voltage, current, temperature and other data. It effectively manages and controls the charging and discharging of the power battery pack and responds to functional requirements at the vehicle level.

[0044] The power battery pack of the above structure has the following advantages:

[0045] (1) The box assembly is designed as a single system, eliminating the upper cover and sealing gasket, reducing the number of parts and reducing costs;

[0046] (2) Compared with aluminum profile welding, the integrated die-casting design of the box body provides a new model for the lightweight application of aluminum alloy die-casting in new energy vehicle power battery systems, with its advantages of high production efficiency and low cost, which may subvert the automotive manufacturing process of aluminum profiles in power battery systems;

[0047] (3) The inverted battery system design is convenient for maintenance and disassembly; the large-area cooling and inverted installation of the module cells facilitates the smooth exhaust and smoke discharge in the event of thermal runaway.

[0048] The present invention also provides a vehicle, comprising a power battery pack of the above structure. The specific structure of the power battery pack can be referred to Figures 1 to 5 Since the vehicle of the present invention includes the power battery pack in the above embodiment, it has all the advantages of the above power battery pack.

[0049] The present invention also provides a method for assembling a power battery pack, comprising the following steps:

[0050] S1. Install the box assembly 1;

[0051] S2. Install the module assembly 6, the BDU assembly and the BMS management system into the box assembly 1 from the bottom of the box assembly 1;

[0052] S3. Install the bottom guard plate 7 at the bottom of the box assembly 1.

[0053] During assembly, the module assembly 6 can be installed into the inner cavity of the box assembly 1 from the bottom of the box assembly 1, and the first bolt 10 is inserted into the through hole of the module assembly 6 from the bottom of the module assembly 6, and then inserted into the first mounting hole, and finally tightened with the first nut 12 to achieve fixed installation of the module assembly 6.

[0054] In the above step S2, during assembly, the module assembly 6 can be installed into the inner cavity of the box assembly 1 from the bottom of the box assembly 1, and the first bolt 10 is inserted into the through hole of the module assembly 6 from the bottom of the module assembly 6, and then inserted into the first mounting hole, and finally tightened with the first nut 12 to achieve fixed installation of the high-voltage distribution module.

[0055] In the above step S2, during assembly, the high-voltage distribution module can be installed into the inner cavity of the box assembly 1 from the bottom of the box assembly 1, and the second bolt 11 is inserted into the through hole of the high-voltage distribution module from the bottom of the high-voltage distribution module, and then inserted into the second mounting hole, and finally tightened with the second nut to achieve fixed installation of the high-voltage distribution module.

[0056] In the above step S3, during assembly, the bottom guard plate 7 is fixedly installed on the bottom of the box assembly 1 using a third bolt below the box assembly 1.

[0057] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. Power battery pack, including box assembly and module assembly, It is characterized in that The box assembly is an integrated structure formed by integral die-casting and having a hollow interior. The module assembly is located in the inner cavity of the box assembly, and a bottom guard plate is provided at the bottom of the box assembly.

2. The power battery pack according to claim 1, It is characterized in that The box assembly includes a top wall and a plurality of side walls arranged on the top wall and extending toward the bottom of the top wall, the bottom guard plate is located below the side wall and connected to the side wall, and the module assembly is located between the top wall and the bottom guard plate.

3. The power battery pack according to claim 2, It is characterized in that A fixing device is arranged in the inner cavity of the box assembly, and the module assembly is mounted on the fixing device by a first bolt. The first bolt passes through the module assembly from below and is inserted into a first mounting hole on the fixing device.

4. The power battery pack according to claim 3, It is characterized in that The fixing device is provided with a first nut matched with the first bolt, and the first nut is located between the fixing device and the top wall.

5. The power battery pack according to claim 3 or 4, It is characterized in that A high-voltage distribution module is arranged in the inner cavity of the box assembly, and the high-voltage distribution module is mounted on the fixing device by a second bolt, and the second bolt passes through the high-voltage distribution module from the bottom and is inserted into the second mounting hole on the fixing device.

6. The power battery pack according to claim 5, It is characterized in that The fixing device is provided with a second nut matched with the second bolt, and the second nut is located between the fixing device and the top wall.

7. The power battery pack according to any one of claims 3 to 6, It is characterized in that The fixing device comprises a longitudinal beam, a plurality of longitudinal beams are provided, and the longitudinal beams are fixedly connected to the box assembly.

8. The power battery pack according to any one of claims 1 to 7, It is characterized in that A protective coating is provided on the bottom surface of the bottom guard plate.

9. Vehicles, It is characterized in that Comprising a power battery pack as described in any one of claims 1 to 8.

10. The method for assembling a power battery pack according to any one of claims 1 to 8, It is characterized in that Includes steps: S1, installing the box assembly; S2, installing the module assembly into the box assembly from the bottom of the box assembly; S3. Install the bottom guard plate at the bottom of the box assembly.

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