BDU and battery pack for passenger car

Abstract

The utility model relates to the technical field of new energy automobile battery packs, in particular to a BDU and a battery pack for a passenger car, which comprises a lower shell and an upper shell cover, the lower shell comprises a bottom plate and a coaming, the bottom plate and the coaming form an installation space, and a first installation boss and a second installation boss are respectively arranged on the front side and the rear side of the installation space. A first mounting area is formed between the first mounting boss and the second mounting boss, a main fuse, a main negative relay, a main positive relay and a heating relay are sequentially arranged in the first mounting area from left to right, the heating relay and the main positive relay are arranged in parallel, and a shunt and a fast charging fuse are sequentially arranged on the second mounting boss from top to bottom. And the fast charging fuse is connected in series with the main positive relay. According to the utility model, by optimizing the space layout and the heat dissipation performance, the technical problems of large size and poor heat dissipation performance of the existing BDU can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy vehicle battery packs, in particular to a BDU and a battery pack for passenger cars. Background Technique

[0002] The rapid development of the electric vehicle (EV) industry is leading the green revolution in the global transportation field. As the core component of electric vehicles, the power battery PACK not only bears the heavy responsibility of vehicle energy supply, but also is a key factor affecting the cost and performance of the whole vehicle. Among them, the Battery Disconnect Unit (BDU) is a key unit in the power battery PACK, mainly used to control the disconnection and connection of the power battery. Its performance directly affects the safety and reliability of the power battery system. At present, the design of BDU shows diverse characteristics, which can meet the personalized needs of different vehicle models, but there are still common problems such as large volume, low integration, and poor heat dissipation performance. For example: in the new generation of passenger car battery packs developed by our company, the internal space of the battery pack is limited. If the traditional BDU layout method is adopted, it will make the overall package integration layout more complex; in the passenger car environment with limited space, if the internal layout of the battery pack is not appropriate, it will directly affect the passenger capacity, storage space and overall layout optimization of the vehicle.

[0003] Based on this, our company has improved the traditional BDU design, aiming to reduce the volume, weight and optimize the temperature rise control of the BDU on the premise of ensuring complete functions; and finally reduce the occupied space inside the PACK, provide more layout flexibility for the battery modules; at the same time, through optimized thermal management, the heat dissipation efficiency of the system can be improved, the battery life can be extended, and the safety performance of the vehicle can be enhanced. Content of the Utility Model

[0004] The utility model provides a BDU and a battery pack for passenger cars, which can solve the technical problems of the existing BDU such as large volume and poor heat dissipation performance.

[0005] The present application provides the following technical solutions:

[0006] A BDU for passenger cars includes a lower housing and an upper cover. The lower housing includes a bottom plate and a surrounding plate. The bottom plate and the surrounding plate form an installation space. A first installation boss and a second installation boss are respectively arranged on the front and rear sides of the installation space. A first installation area is formed between the first installation boss and the second installation boss. A main fuse, a main negative relay, a main positive relay, and a heating relay are sequentially arranged from left to right in the first installation area. The heating relay is arranged in parallel with the main positive relay. A shunt and a fast charge fuse are sequentially arranged on the second installation boss from top to bottom. The fast charge fuse is connected in series with the main positive relay.

[0007] Beneficial effects:

[0008] 1. Improve space utilization and reduce volume: By dividing the installation space into the first installation boss, the second installation boss and the first installation area, different functional areas are effectively divided to achieve a reasonable layout of functional modules; wherein, the first installation area centrally places the main fuse, the main negative relay and the main positive relay from left to right, so that the components of the main circuit are basically located in the middle of the lower shell, which is convenient for connecting the components in the main circuit and connecting with the components on both sides to form different circuits, effectively avoiding line crossing, and the gaps between the components can be used as the installation area of ​​the wiring harness or copper bus, further improving the utilization of the internal space and reducing the overall volume.

[0009] 2. Good heat dissipation performance and improved system stability: Compared with relays, components such as the main fuse, fast-charging fuse, and shunt in the circuit system of this application have continuous heat generation and large temperature rise, so they require greater heat dissipation. This application can reduce heat accumulation by separately arranging the main fuse, fast-charging fuse, and shunt in different areas of the lower shell. At the same time, these components are arranged at the edge of the lower shell, which is convenient for heat dissipation and maintenance.

[0010] 3. A first mounting boss and a second mounting boss are arranged in the installation space so that a height difference is formed in the entire installation area in the vertical direction, ensuring that the components arranged on the mounting boss and the components arranged in the first mounting area are layered in spatial distribution, which helps to disperse the heat source and avoid local overheating; in addition, the height difference in the vertical direction helps to form natural convection, and the upward flow characteristic of hot air can be utilized to accelerate heat exchange and improve heat dissipation efficiency. Hot air can flow from bottom to top inside the BDU, taking away heat when passing through each mounting boss, and finally discharged from the area with better heat dissipation, forming a natural heat dissipation cycle.

[0011] Furthermore, the first mounting boss is arranged along the length direction of the lower shell, and a pre-charging resistor is arranged on the first mounting boss; the first mounting area is also provided with a pre-charging relay, the pre-charging relay is arranged side by side with the main negative relay, and the pre-charging relay and the pre-charging resistor are connected in series and arranged in parallel with the main positive relay.

[0012] Beneficial effects: By setting the pre-charging resistor on the first mounting boss along the length direction of the lower shell, the lateral space can be fully utilized, and the crowding of components in the longitudinal space can be avoided, which helps to achieve a more compact and efficient circuit layout; this layout method not only reduces the complexity of the circuit, but also facilitates maintenance and troubleshooting, and improves assembly efficiency.

[0013] Further, a partition is provided between the main fuse and the main negative relay. The partition divides the first installation area into left and right regions. The main fuse is arranged in the left region and is arranged along the width direction of the lower housing.

[0014] Beneficial effects:

[0015] 1. Electrical isolation: By dividing the first installation area into left and right regions through the partition, effective electrical isolation between the main fuse and the main negative relay can be achieved, reducing the possibility of electrical interference, enhancing the stability and safety of the circuit; in a high-voltage environment, this physical isolation helps prevent the spread of faults caused by short circuits or insulation failures and protects other circuit components from being affected.

[0016] 2. Improve heat dissipation and optimize the space layout: The main fuse generates heat during operation. Arranging it along the width direction of the lower housing can increase the contact area between the components and the housing, facilitating the rapid dissipation of heat; in addition, the main fuse is arranged at the leftmost side of the lower housing and is arranged along its width direction, making full use of the longitudinal space, avoiding the heat dissipation and maintenance problems that may be brought about by horizontal stacking. This layout method not only helps to achieve a compact design but also facilitates the installation and replacement of components, reducing the assembly difficulty and cost.

[0017] Further, a second installation area is also provided on the right side of the first installation area. A heating fuse is provided in the second installation area, and the heating fuse is connected in series with the heating relay.

[0018] Beneficial effects: Setting the heating fuse independently in the second installation area avoids the superposition of heat sources with other key components, which is beneficial to heat dissipation and fault isolation, and improves the overall stability and safety of the system.

[0019] Further, a plug-in area is also provided on the outer side of the surrounding plate of the lower housing near the second installation area. A heating plug is installed in the plug-in area, and the heating plug is used to connect the heating circuit.

[0020] Beneficial effects: By providing a heating plug on the outer side of the surrounding plate of the lower housing, the rapid access and disassembly of the heating circuit are realized. This design makes the installation, debugging, and later maintenance of the heating system simpler and faster. There is no need to disassemble the entire BDU, and only operations need to be carried out in the plug-in area, greatly saving maintenance time and labor costs.

[0021] Further, an extension boss is also provided on the right side of the second installation area. A wiring terminal is provided on the extension boss. The wiring terminal includes a fast charging positive wiring terminal and a fast charging negative wiring terminal, and the fast charging positive wiring terminal and the fast charging negative wiring terminal are arranged in a large and small manner.

[0022] Beneficial effects:

[0023] 1. By designing fast - charging positive and negative connection terminals with different sizes, the possibility of polarity errors during wiring can be significantly reduced. When connecting cables or wires, the connection terminals of different sizes only allow matching with corresponding - sized connectors. This physical incompatibility effectively prevents the reversal of the positive and negative poles, avoiding short - circuits, equipment damage, or safety risks caused by polarity errors.

[0024] 2. The design of connection terminals with different sizes simplifies the judgment process during assembly; when connecting cables, there is no need to additionally check the polarity markings. The correct connection method can be judged solely by the size of the connection terminals, which speeds up the assembly process, reduces the probability of human error, and improves the accuracy and one - time success rate of assembly.

[0025] Furthermore, the bottom plate is provided with an opening in the area of the first mounting boss and the second mounting boss, and the interiors of the first mounting boss and the second mounting boss are of hollow structures; the fast - charging fuse is arranged inside the second mounting boss, and the shunt is arranged on the top of the boss of the second mounting boss through a mounting post.

[0026] Beneficial effects:

[0027] 1. The bottom plate is provided with an opening in the area of the first mounting boss and the second mounting boss. Combined with the hollow - structure design inside the bosses, the weight of the BDU is significantly reduced, and overall structural lightweighting is achieved.

[0028] 2. The hollow - structure and bottom - plate opening design are conducive to internal air circulation, enhancing the natural convection effect; and placing the fast - charging fuse inside the hollow structure can utilize the heat - dissipation channels of the hollow structure for targeted cooling, avoiding heat accumulation and reducing the impact of thermal stress on components.

[0029] Furthermore, a number of reinforcing ribs arranged in a criss - cross pattern are also provided on the bottom plate.

[0030] Beneficial effects: The criss - cross arrangement of the reinforcing ribs can enhance the strength and service life of the lower housing without significantly increasing the weight of the BDU.

[0031] Furthermore, a main positive interface, a main negative interface, a fast - charging interface, a battery positive interface, and a battery negative interface are provided on the upper cover.

[0032] A battery pack for a passenger car includes a battery box. A battery module is arranged inside the battery box, and a BDU is also arranged inside the battery box. The BDU is electrically connected to the battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the overall structure of the BDU of the present utility model;

[0034] Figure 2 ForFigure 1 Top view;

[0035] Figure 3 Structural schematic diagram of the lower housing;

[0036] Figure 4 is Figure 3 Schematic diagram in another direction in

[0037] Figure 5 Arrangement schematic diagram of components;

[0038] Figure 6 is Figure 5 Schematic diagram of the other side;

[0039] Figure 7 Schematic diagram of components installed on the lower housing (the side panel on one side of the lower housing is omitted);

[0040] Figure 8 Partial structural schematic diagram of the battery pack in Embodiment 2. Specific embodiments

[0041] The following is a further detailed description through specific embodiments:

[0042] The markings in the accompanying drawings of the specification include: lower housing 1, reinforcing rib 101, first mounting boss 12, second mounting boss 11, first mounting area 13, second mounting area 131, partition 14, extending boss 15, upper shell cover 2, main positive interface 211, main negative interface 212, battery positive interface 221, battery negative interface 222, fast charging interface 23, main fuse 31, main negative relay 32, main positive relay 33, shunt 34, heating relay 41, heating fuse 42, heating plug 43, fast charging fuse 5, fast charging positive terminal 51, fast charging negative terminal 52, pre-charge relay 61, pre-charge resistor 62, battery box 200, battery module 201.

[0043] Embodiment 1

[0044] As Figure 1 shown, a BDU for a passenger car includes a lower housing 1 and an upper shell cover 2. The lower housing 1 includes a bottom plate and a side panel, and the bottom plate and the side panel form an installation space. In this embodiment, the bottom plate and the side panel are integrally formed. As Figure 4 shown, a plurality of reinforcing ribs 101 arranged vertically and horizontally are further provided at the bottom of the bottom plate to enhance the strength of the lower housing 1.

[0045] As Figure 3As shown, a first mounting boss 12 and a second mounting boss 11 are respectively arranged on the front and rear sides of the installation space. Both the first mounting boss 12 and the second mounting boss 11 are arranged along the length direction of the lower housing 1, and a first installation area 13 is formed between the first mounting boss 12 and the second mounting boss 11; As Figure 4 shown, in this embodiment, the interiors of the first mounting boss 12 and the second mounting boss 11 are of hollow structure, and the bottom plate is arranged with an opening in the area of the first mounting boss 12 and the second mounting boss 11. Such a setting is not only convenient for heat dissipation but also can reduce the weight of the lower housing 1.

[0046] A plurality of heat dissipation holes are also opened on the top plate of the first mounting boss 12. As Figure 7 shown, a pre-charge resistor 62 is arranged on the first mounting boss 12; As Figure 6 shown, a shunt 34 and a fast charge fuse 5 are successively arranged on the second mounting boss 11 from top to bottom. Specifically, the fast charge fuse 5 is arranged inside the second mounting boss 11, and the shunt 34 is arranged on the top of the boss of the second mounting boss 11 through a mounting post; In this embodiment, in order to protect the fast charge fuse 5, a bottom guard plate (not shown in the figure) can be arranged in the opening area of the bottom plate. The bottom guard plate is connected to the bottom plate by screws, which is convenient for opening the bottom guard plate to replace or repair the fast charge fuse 5.

[0047] As Figure 3 shown, the first installation area 13 is located in the middle area of the lower housing 1 and extends along the length direction of the lower housing 1. Specifically, as Figure 5-6 shown, a main fuse 31, a main negative relay 32, a pre-charge relay 61, a main positive relay 33, and a heating relay 41 are successively arranged in the first installation area 13 from left to right. The main fuse 31, the main negative relay 32, the main positive relay 33, and the shunt 34 form a main circuit for controlling the discharge of the battery pack; Among them, the pre-charge relay 61 and the main negative relay 32 are arranged side by side, and the pre-charge relay 61 is connected in series with the pre-charge resistor 62 and then connected in parallel with the main positive relay 33.

[0048] In this embodiment, the pre-charge relay 61 and the pre-charge resistor 62 form a pre-charge circuit, which is mainly used for pre-charging the high-voltage capacitor during startup or restart; Through the current-limiting effect of the pre-charge resistor 62, it is possible to avoid a large current directly impacting the battery management system (BMS) and related electronic devices when the high-voltage power supply is connected instantaneously, thereby protecting the circuit from excessive voltage surges and improving the safety and stability of the entire system.

[0049] As Figure 3As shown, a partition plate 14 is also provided between the main fuse 31 and the main negative relay 32. The partition plate 14 divides the first installation area 13 into two left and right areas. The main fuse 31 is arranged in the left area and is arranged along the width direction of the lower housing 1. A large amount of heat will be generated when the main fuse 31 is working. Setting it independently in an installation space can, on the one hand, play an electrical isolation role, and on the other hand, arranging it along the width direction of the lower housing 1 and being located at the leftmost side of the lower housing 1 is beneficial to increasing the contact area between the components and the housing, facilitating the rapid dissipation of heat. In addition, this layout method also helps to achieve a compact design, and at the same time is convenient for the installation and replacement of components, reducing the assembly difficulty and cost.

[0050] On the right side of the first installation area 13, there is also a second installation area 131. A heating fuse 42 is arranged in the second installation area 131. The heating fuse 42 and the heating relay 41 are connected in series to form a heating circuit. On the outer side of the surrounding plate of the lower housing 1 close to the second installation area 131, there is also a plug-in area, as Figure 2 shown. A heating plug 43 is installed in the plug-in area. The heating plug 43 is used to connect the heating circuit. Specifically, one end of the heating plug 43 is connected to the heating film arranged outside the battery pack by a wire, and the other end is connected to the heating fuse 42. In this embodiment, the heating plug 43 is arranged on the outer side of the lower housing 1, realizing the quick access and disassembly of the heating circuit. This design makes the installation, debugging and later maintenance of the heating system more simple and fast. There is no need to disassemble the entire BDU, and only operations need to be carried out in the plug-in area, greatly saving maintenance time and labor costs.

[0051] Specifically, when heating is required, two heating methods can be realized according to actual needs: 1. Pre-charging heating. First, close the heating relay 41 to make the heating film of the battery pack start to work. After heating is completed, disconnect the heating relay 41, and then close the main positive relay 33 and the main negative relay 32 to make the battery pack start to charge; 2. During discharge heating, the main positive relay 33 and the main negative relay 32 have been closed. At this time, only need to directly close the heating relay 41 to connect the heating circuit, make the heating film start to work, and heat the battery pack. After heating is completed, disconnect the heating relay 41.

[0052] The fast charging fuse 5 is connected in series with the main positive relay 33 to form a fast charging circuit, which can realize charging and discharging at the same time. Specifically, on the right side of the second installation area, there is also an extended boss 15. There are also connection terminals for connecting with the fast charging fuse 5 on the extended boss 15. The connection terminals include a fast charging positive connection terminal 51 and a fast charging negative connection terminal 52, and the fast charging positive connection terminal 51 and the fast charging negative connection terminal 52 are set in different sizes. Such a setting can significantly reduce the possibility of polarity errors during wiring, and the design of connection terminals with different sizes simplifies the judgment link during the assembly process, speeding up the assembly speed and the accuracy of assembly.

[0053] The fast charging circuit is arranged after the main circuit and is set in series with the main circuit. There is no need to use a separate relay to control the fast charging circuit. When the battery pack discharges, the main positive relay 33 and the main negative relay 32 are closed. At this time, the fast charging circuit for charging will also be connected. If there is a power supply at the vehicle end to charge the vehicle, the external power supply can charge the battery pack through the fast charging circuit, realizing the functions of simultaneous charging and discharging.

[0054] As Figure 1 shown, in this embodiment, the upper shell cover 2 is provided with a main positive interface 211, a main negative interface 212, a fast charging interface 23, a battery positive interface 221, and a battery negative interface 222. Among them, the battery positive interface 221 and the battery negative interface 222 are used to connect with the batteries in the battery pack, and the main positive interface 211, the main negative interface 212, and the fast charging interface 23 are used to connect with the power supply equipment and charging interfaces outside the battery pack; the surface of the upper shell cover 2 is also provided with an identification area, and the identification area includes warning signs, model signs, etc.

[0055] In this application, by arranging the installation space in different areas and separately setting components with large heat dissipation requirements such as fuses and shunts 34 at different edge positions of the installation space, the accumulation of heat sources is reduced, and the heat dissipation performance is improved; at the same time, different types of components form a height difference in the vertical direction of the installation area, avoiding the congestion of components in the planar space, which helps to achieve a more compact and efficient circuit layout, optimize the overall volume of the BDU, and improve the space utilization rate.

[0056] In summary, under the premise of ensuring complete functions, this application achieves the purpose of reducing the volume of the BDU and optimizing the temperature rise control; and finally reduces the occupied space inside the PACK, providing more layout flexibility for the battery module 201; at the same time, the optimized thermal management improves the heat dissipation efficiency of the system, extends the battery life, and enhances the safety performance of the vehicle.

[0057] Embodiment 2

[0058] This embodiment provides a battery pack for a passenger vehicle. As Figure 8 shown, it includes a battery box 200. A battery module 201 is arranged inside the battery box 200. The BDU disclosed in Embodiment 1 is also arranged inside the battery box 200, and the BDU is electrically connected to the battery module 201.

[0059] The above are only the embodiments of the present utility model. The utility model is not limited to the fields involved in this embodiment case. Common knowledge such as the specific structures and characteristics known in the solution is not described in detail herein. It should be noted that for those skilled in the art, without departing from the structure of the present utility model, several deformations and improvements can still be made, and these should also be regarded as the protection scope of the present utility model, and these will not affect the implementation effect of the present utility model and the practicality of the patent. The protection scope required by this application shall be subject to the content of its claims, and the specific implementation manners and the like recorded in the specification can be used to interpret the content of the claims.

Claims

1. A BDU for a passenger car, comprising a lower shell and an upper shell cover, wherein the lower shell comprises a bottom plate and a surrounding plate, wherein the bottom plate and the surrounding plate form an installation space, wherein: The first mounting boss and the second mounting boss are respectively arranged on the front and rear sides of the mounting space, and the first mounting area is formed between the first mounting boss and the second mounting boss. The main fuse, the main negative relay, the main positive relay, and the heating relay are arranged in sequence from left to right in the first mounting area. The heating relay is arranged in parallel with the main positive relay. The second mounting boss is arranged with a shunt and a fast-charging fuse in sequence from top to bottom, and the fast-charging fuse is connected in series with the main positive relay.

2. A BDU for a passenger car according to claim 1, characterized in that: The first mounting boss is arranged along the length direction of the lower shell, and a pre-charging resistor is arranged on the first mounting boss; a pre-charging relay is also arranged in the first mounting area, the pre-charging relay is arranged side by side with the main negative relay, and the pre-charging relay and the pre-charging resistor are connected in series and arranged in parallel with the main positive relay.

3. A BDU for a passenger car according to claim 2, characterized in that: A partition is also arranged between the main fuse and the main negative relay, and the partition divides the first installation area into two left and right areas. The main fuse is arranged in the left area, and the main fuse is arranged along the width direction of the lower shell.

4. A BDU for a passenger car according to claim 3, characterized in that: A second installation area is also arranged on the right side of the first installation area. A heating fuse is arranged on the second installation area. The heating fuse is connected in series with the heating relay.

5. A BDU for a passenger car according to claim 4, characterized in that: The lower shell is also provided with an inserting area on the outer side of the enclosure close to the second installation area, and a heating plug-in is installed in the inserting area. The heating plug-in is used to connect the heating circuit.

6. A BDU for a passenger car according to claim 5, characterized in that: An extended boss is also provided on the right side of the second installation area, and binding posts are provided on the extended boss. The binding posts include a fast-charging positive pole binding post and a fast-charging negative pole binding post. The fast-charging positive pole binding post and the fast-charging negative pole binding post are arranged in one large and one small.

7. A BDU for a passenger car according to claim 6, characterized in that: The base plate is located in the regional opening of the first mounting boss and the second mounting boss, and the interior of the first mounting boss and the second mounting boss are hollow structures; the fast-charging fuse is arranged inside the second mounting boss, and the diverter is arranged on the top of the boss of the second mounting boss through the mounting column.

8. The BDU for a passenger car according to claim 1, characterized in that: The bottom plate is also provided with a plurality of reinforcing ribs arranged in a crisscross pattern.

9. A BDU for a passenger car according to claim 8, characterized in that: The upper shell cover is provided with a main positive interface, a main negative interface, a fast charging interface, a battery positive electrode interface, and a battery negative electrode interface.

10. A battery pack for a passenger car, comprising a battery box, wherein a battery module is arranged in the battery box, characterized in that: The battery box is also provided with a BDU for a passenger car as described in any one of claims 1 to 9, and the BDU is electrically connected to the battery module.

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