Battery disconnect unit (BDU) and battery pack

Abstract

Provided in the present application are a BDU and a battery pack. The BDU comprises a housing, an electrical assembly, a busbar and a heat dissipation module, wherein the housing comprises a bottom plate; the electrical assembly is mounted in the housing, and is arranged on the bottom plate; the busbar is arranged on the bottom plate, and is electrically connected to the electrical assembly, and the busbar is integrally formed with the bottom plate; and the heat dissipation module is arranged on the housing, and is in heat transfer connection with the busbar. In the present application, the busbar is integrally formed on the bottom plate, such that the difficulty in mounting the busbar on the housing can be reduced, and the bottom plate can provide a stable support for the busbar, thereby enhancing the overall structural rigidity of the busbar, and preventing vibrations, fatigue, etc., caused by a suspended arrangement of the busbar. Moreover, the busbar is arranged on the bottom plate, such that the internal space of the housing can be saved on, the layout design and wiring process of the electrical assembly in an accommodating cavity are simplified, and the production difficulty is reduced, thereby improving the production efficiency and operational stability of the BDU and the battery pack.

Description

Battery pack circuit breaker unit and battery pack

[0001] This application claims priority to Chinese Patent Application No. 202521493830.2, filed on July 16, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of new energy battery technology, specifically to a BDU and battery pack. Background Technology

[0003] Currently, the design of battery disconnect units (BDUs) is mainly based on the current magnitude, selecting devices with corresponding rated current for current carrying. With the increasing market demand for high-current fast charging, the proportion of high-rated current and high-specification current devices in the battery pack has increased. In order to maintain the same range, the overall size of the battery pack has to be increased, resulting in increased production and installation costs. Moreover, the heat dissipation performance of current devices has decreased significantly, affecting the safety and stability of the battery pack.

[0004] Technical issues

[0005] To meet market demands for high-current fast charging in situations with limited electrical space, a liquid-cooled BDU module has been developed. This module, housed within the BDU housing, features a liquid-cooling module that makes close contact with the corresponding copper busbar. This effectively cools the internal copper busbar, ensuring its current-carrying capacity and avoiding the need for high-rated-current, high-specification electrical components. However, because the liquid-cooling module is mounted on the housing, ensuring close contact requires suspending the copper busbar within the BDU module. This can lead to vibration and fatigue, reducing heat dissipation and significantly increasing the difficulty of installing the copper busbar and its arrangement with other electrical components. Ultimately, this impacts the BDU module's production efficiency and operational stability. Summary of the Invention

[0006] In a first aspect, embodiments of this application provide a BDU, comprising: a housing, including a base plate; an electrical component, installed inside the housing and disposed on the base plate; a busbar, disposed on the base plate and electrically connected to the electrical component, wherein the busbar and the base plate are integrally formed; and a heat dissipation module, disposed on the base plate and heat-transfer connected to the busbar.

[0007] In one or more embodiments, the electrical component includes a current device and a latching member, the current device being electrically connected to the busbar and having a connection portion, and the latching member being configured to lock the connection portion and the busbar so that the current device is latched onto the busbar.

[0008] In one or more embodiments, the base plate is provided with an embedding groove and a first clearance hole, the busbar is integrally formed and disposed in the embedding groove, the embedding groove is provided with a heat dissipation port on the side facing the heat dissipation module, the busbar is connected to the heat dissipation module through the heat dissipation port, the first clearance hole is connected to the embedding groove, the first clearance hole is correspondingly disposed in the connecting part, and the locking member passes through the busbar and the first clearance hole and is locked and connected to the connecting part.

[0009] In one or more embodiments, the busbar is provided with a recessed groove on the side facing the heat dissipation module, and a connecting through hole is provided at the bottom of the recessed groove. The connecting through hole is directly opposite to the first clearance hole. The end of the locking member facing the connecting part passes through the connecting through hole and the first clearance hole and is locked to the connecting part. The end of the locking member facing the heat dissipation module is recessed in the recessed groove.

[0010] In one or more embodiments, the locking member is a locking bolt, the connecting portion is provided with a threaded hole, the threaded hole is disposed opposite to the connecting through hole and the first clearance hole, the threaded portion of the locking bolt passes through the connecting through hole and the first clearance hole and is threadedly connected to the threaded hole, and the end cap of the locking bolt is recessed in the groove.

[0011] In one or more embodiments, the heat dissipation module includes a liquid cooling plate and a thermally conductive layer. The liquid cooling plate is disposed opposite to the heat dissipation port, and the thermally conductive layer is tightly fitted between the busbar and the liquid cooling plate, so that the liquid cooling plate is connected to the busbar through the thermally conductive layer for heat transfer; and / or,

[0012] The thermally conductive layer is a structural adhesive curing layer. The heat dissipation port has an annular adhesive-blocking edge protruding from the periphery of the opening end facing the liquid cooling plate. The annular adhesive-blocking edge surrounds the busbar to form a filling space, and the filling space is filled with the structural adhesive curing layer.

[0013] In one or more embodiments, the current device includes a relay, the relay having relay contacts configured as the connection portion;

[0014] The current device includes a main fuse, and a conductive support post is connected to the outside of the main fuse. The conductive support post is configured as the connection part.

[0015] In one or more embodiments, a BDU interface is provided on the periphery of the housing, the BDU interface including a BDU positive input interface, a BDU positive output interface, a BDU negative input interface, and a BDU negative output interface; the relay includes a main positive relay and a main negative relay; the busbar includes a first copper busbar, a second copper busbar, a third copper busbar, and a fourth copper busbar, wherein:

[0016] The conductive support post on one side of the main fuse is connected to the positive input interface of the BDU;

[0017] One end of the first copper busbar is connected to the conductive support column on the other side of the main fuse, and the other end of the first copper busbar is connected to one end of the main positive relay;

[0018] One end of the second copper busbar is connected to the other end of the main positive relay, and the other end of the second copper busbar extends to be connected to the positive output interface of the BDU;

[0019] One end of the third copper busbar is connected to the negative input interface of the BDU, and the other end of the third copper busbar is connected to one end of the main negative relay;

[0020] One end of the fourth copper busbar is connected to the other end of the main negative relay, and the other end of the fourth copper busbar extends to connect to the negative output interface of the BDU.

[0021] In one or more embodiments, the periphery of the housing is provided with a BDU interface, the bottom plate is provided with a second clearance hole, and at least two mounting grooves are provided, with at least one mounting groove corresponding to the second clearance hole;

[0022] The busbar includes a first busbar and a second busbar. The first busbar is integrally formed in the mounting groove and has a connection through hole. The second busbar is bent and one end is connected to the first busbar through the second clearance hole. The other end of the second busbar is connected to the BDU interface.

[0023] Secondly, embodiments of this application provide a battery pack, including module cells and the aforementioned BDU, wherein the module cells are electrically connected to the BDU.

[0024] The beneficial effects of this application are:

[0025] In the BDU provided in this embodiment, since the busbar is integrally molded onto the base plate, the installation difficulty of the busbar on the housing is effectively reduced, and the base plate can be fixedly connected to the busbar. This allows the base plate to provide stable support for the busbar, thereby enhancing the overall structural rigidity of the busbar and avoiding vibration and fatigue caused by the busbar being suspended in the air. This ensures that the busbar is not prone to vibration and deformation during the operation of electrical components. Moreover, placing the busbar on the base plate saves internal space in the housing, simplifies the layout design and wiring process of electrical components in the cavity, reduces production difficulty, and thus effectively improves the production efficiency and operational stability of the BDU. Attached Figure Description

[0026] Figure 1 is a general assembly diagram of the BDU provided in an embodiment of this application;

[0027] Figure 2 is an exploded view of the BDU provided in the embodiment of this application;

[0028] Figure 3 is a magnified view of part A in Figure 1;

[0029] Figure 4 is a top view of the BDU hidden cover plate provided in the embodiment of this application;

[0030] Figure 5 is a cross-sectional view along BB in Figure 4;

[0031] Figure 6 is a cross-sectional view along CC in Figure 4;

[0032] Figure 7 is a bottom view of the BDU hidden cover plate provided in the embodiment of this application;

[0033] Figure 8 is a cross-sectional view along point DD in Figure 7;

[0034] Figure 9 is a magnified view of part E in Figure 8;

[0035] Figure 10 is a schematic diagram of the structure after the hidden locking components and busbar in Figure 9;

[0036] Figure 11 is a magnified view of a portion of point F in Figure 7;

[0037] Figure 12 is a schematic diagram of the structure of the electrical components and bus provided in the embodiment of this application after assembly;

[0038] Figure 13 is a top view of the electrical components and bus provided in the embodiment of this application after assembly;

[0039] Figure 14 is a partial schematic diagram of the base plate provided in an embodiment of this application;

[0040] Figure 15 is a schematic diagram of the battery pack provided in an embodiment of this application;

[0041] In the picture:

[0042] 10. BDU;

[0043] 1. Housing; 11. Base plate; 111. Mounting groove; 1111. Heat dissipation vent; 112. First clearance hole; 113. Annular adhesive retaining edge; 1131. Filling space; 114. Second clearance hole; 12. Side wall plate; 121. Locking protrusion; 122. Mounting ear; 13. Cover plate; 131. Snap-fit ​​structure; 141. BDU positive input interface; 142. BDU positive output interface; 143. BDU negative input interface; 144. BDU negative output interface; 1451. Fast charging positive interface; 1452. Fast charging negative interface; 1461. Range extender positive interface; 1462. Range extender negative interface;

[0044] 2. Electrical components; 210. Connecting part; 2101. Threaded hole; 211. Relay; 2111. Relay contact; 2112. Main positive relay; 2113. Main negative relay; 2114. Fast charging positive relay; 2115. Fast charging negative relay; 212. Main fuse; 2121. Conductive support post; 213. Precharge relay; 214. Precharge resistor; 215. Current sensor; 216. NTC; 217. HMU; 218. DC-DC fuse; 22. Locking component;

[0045] 3. Busbar; 301. Recessed groove; 302. Connecting through hole; 310. First busbar; 320. Second busbar; 31. First copper busbar; 32. Second copper busbar; 33. Third copper busbar; 34. Fourth copper busbar; 35. Fifth copper busbar; 36. Sixth copper busbar;

[0046] 4. Heat dissipation module; 41. Liquid cooling plate. Detailed Implementation

[0047] The present application will now be described in conjunction with the accompanying drawings and embodiments. The embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the application. For ease of description, only the parts relevant to the present application are shown in the drawings, not the entire structure.

[0048] In the description of this application, unless otherwise specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. The meaning of the above terms in this application can be understood according to the actual situation.

[0049] In this application, unless otherwise specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or indicating that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or indicating that the first feature is at a lower horizontal level than the second feature.

[0050] In the description of this embodiment, the terms "upper," "lower," "right," and "left," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first" and "second" are used for distinction in description and have no special meaning.

[0051] The technical solution provided in this application will be described below with reference to the accompanying drawings and embodiments.

[0052] Referring to Figures 1 to 13, this embodiment provides a battery pack BDU 10, which includes a housing 1, electrical components 2, a busbar 3, and a heat dissipation module 4. The housing 1 includes a base plate 11. The electrical components 2 are installed within a cavity of the housing 1 and disposed on the base plate 11. The busbar 3 is disposed on the base plate 11 and electrically connected to the electrical components 2, and the busbar 3 is integrally formed with the base plate 11. The heat dissipation module 4 is disposed on the base plate 11 and thermally connected to the busbar 3.

[0053] In the above configuration, since the busbar 3 is integrally molded onto the base plate 11, the installation difficulty of the busbar 3 on the housing 1 is effectively reduced, and the base plate 11 can be fixedly connected to the busbar 3. This allows the base plate 11 to provide stable support for the busbar 3, thereby enhancing the overall structural rigidity of the busbar 3 and avoiding vibration and fatigue caused by the busbar 3 being suspended. This ensures that the busbar 3 is not prone to vibration and deformation during the operation of the electrical components 2. Moreover, placing the busbar 3 on the base plate 11 saves internal space in the housing 1, simplifies the layout design and wiring process of the electrical components 2 in the cavity, reduces production difficulty, and thus effectively improves the production efficiency and operational stability of the BDU 10.

[0054] This application provides a BDU and a battery pack, which optimizes the layout design of the liquid cooling module in the BDU, improves the stability of the copper busbar, reduces the difficulty of copper busbar installation and layout between the copper busbar and multiple electrical components, ensures the efficient production and stable use of the BDU, thereby improving the production efficiency and quality of the battery pack.

[0055] In this embodiment, the busbar 3 is made of a conductive metal material, such as copper or aluminum, to ensure good conductivity and heat dissipation. The base plate 11 is manufactured using a high-strength composite insulating material, such as plastic, which not only effectively isolates the electrical components 2 from the housing 1 but also possesses excellent mechanical strength, ensuring the overall structural stability. The busbar 3 and the base plate 11 are fixedly connected by an integral injection molding process, meaning that the base plate 11 is directly injection molded during production. The housing 1 provided in this embodiment also includes a side wall plate 12, which is connected to the base plate 11 to form a receiving cavity. The side wall plate 12 and the base plate 11 can be fixedly connected by an integral injection molding process, meaning that the base plate 11, side wall plate 12, and busbar 3 are directly injection molded into an integral connection during production.

[0056] The housing 1 also includes a cover plate 13, which, after being sealed onto the side wall plate 12, forms a closed receiving cavity to insulate and isolate the internal electrical components 2 from the external environment, ensuring the safety of the electrical components 2 in use. The cover plate 13 is made of plastic sheet to achieve the purpose of housing 1 insulating and sealing the electrical components 2 within the mounting cavity.

[0057] The cover plate 13 and the side wall plate 12 are fixedly connected by snaps or screws to ensure sealing and firmness, and also facilitate the disassembly and assembly of the cover plate 13, making it convenient for maintenance and upkeep of the electrical components 2 inside the installation cavity. In one embodiment, referring to Figures 2 and 3, the housing 1 is generally square. The cover plate 13 has snap-fit ​​structures 131 on all four sides, and corresponding latching protrusions 121 are provided on the side wall plate 12. After the cover plate 13 is placed on the side wall plate 12, the snap-fit ​​structures 131 can be locked onto the latching protrusions 121, thereby achieving a sealed and fixed arrangement of the cover plate 13 and the side wall plate 12. After the snap-fit ​​structures 131 are detached from the latching protrusions 121, the cover plate 13 can be easily opened for inspection or replacement of the internal electrical components 2.

[0058] To prevent interference with the installation of the cover plate 13 due to assembly tolerances of the electrical component 2, a clearance is provided between the snap-fit ​​structure 131 and the snap protrusion 121 in the horizontal direction. This clearance is typically small, ensuring a sealed connection even if there is relative horizontal displacement between the cover plate 13 and the side wall plate 12. By setting this clearance, assembly tolerances of the side wall plate 12, electrical component 2, and cover plate 13 can be effectively absorbed, thereby ensuring the installation efficiency of the cover plate 13.

[0059] Optionally, the outer side wall of the side panel 12 is provided with a plurality of mounting ears 122 for mounting the BDU 10. In this embodiment, there are 6 mounting ears 122, arranged in groups of three, with two groups of mounting ears 122 arranged on opposite sides of the side panel 12. The center of each mounting ear 122 is provided with a bolt through hole. By engaging the mounting ears 122 with bolts, the housing 1 of the BDU 10 can be fixed inside the battery pack.

[0060] In one embodiment, the electrical component 2 includes a current device and a locking member 22. The current device is electrically connected to the busbar 3 and has a connecting portion 210. When the busbar 3 is integrally formed on the base plate 11, the locking member 22 can lock the connecting portion 210 and the busbar 3, so that the current device can be locked and fixed on the busbar 3. Exemplarily, in this embodiment, referring to FIG5, the current device includes a relay 211. The relay 211 has a relay contact 2111, which is set as the connecting portion 210. The locking member 22 fixes the relay contact 2111 to the busbar 3, so that the relay 211 can be directly fixed in the mounting cavity by the locking member 22. Compared to the conventional design, which involves embedding a nut in the housing 1, then locking the mounting feet of the relay 211 to the housing 1, and finally locking the relay contacts 2111 to the busbar 3 via fasteners, this design eliminates the need for the nut on the housing 1. In this embodiment, the busbar 3 can not only carry current and conduct heat, but also fix the relay 211, resulting in lower installation costs and higher efficiency.

[0061] In this embodiment, the current device also includes a main fuse 212. A conductive support post 2121 is connected to the outside of the main fuse 212. Referring to Figure 6, a conductive support post 2121 is connected to each side of the main fuse 212. The conductive support post 2121 is also configured as a connecting part 210. The conductive support post 2121 is locked to the busbar 3 by the locking member 22. This also achieves the purpose of directly locking and fixing the main fuse 212 to the busbar 3, eliminating the need for fasteners such as nuts, thereby simplifying the installation steps of the main fuse 212 and improving the installation efficiency of the current device.

[0062] The base plate 11 is provided with an embedding groove 111 and a first clearance hole 112. The busbar 3 is integrally formed and disposed in the embedding groove 111. The embedding groove 111 is provided with a heat dissipation port 1111 on the side facing the heat dissipation module 4. The busbar 3 is connected to the heat dissipation module 4 through the heat dissipation port 1111. The first clearance hole 112 is connected to the embedding groove 111. The first clearance hole 112 is correspondingly disposed in the connecting part 210. The locking member 22 passes through the busbar 3 and the first clearance hole 112 and is locked and connected to the connecting part 210.

[0063] Taking relay 211 as an example, in order to realize that the busbar 3 is integrally molded on the base plate 11, and at the same time, the locking member 22 can fix the busbar 3 and the relay 211, in this embodiment, as shown in Figures 7 to 10, during the process of integral injection molding of the base plate 11 and the busbar 3, the base plate 11 at the position of the busbar 3 can form an embedding groove 111 for embedding the busbar 3. The embedding groove 111 is provided with a heat dissipation port 1111 on the side facing the heat dissipation module 4, and after the base plate 11 is injection molded, a first clearance hole 112 communicating with the embedding groove 111 can be formed at a preset position. After the relay contact 2111 is set at the preset position, the first clearance hole 112 is correspondingly set at the relay contact 2111. In this way, the locking member 22 can pass through the busbar 3 and the first clearance hole 112 in sequence and connect with the relay contact 2111, thereby realizing the purpose of locking the busbar 3 integrally molded with the base plate 11.

[0064] As shown in Figure 9, a recessed groove 301 is provided on the side of the busbar 3 facing the heat dissipation module 4. A connecting through hole 302 is provided at the bottom of the groove 301. The connecting through hole 302 is directly opposite the first clearance hole 112. One end of the locking member 22 facing the connecting part 210 passes through the connecting through hole 302 and the first clearance hole 112 and is locked to the connecting part 210. The end of the locking member 22 facing the heat dissipation module 4 is recessed in the recessed groove 301 to prevent the locking member 22 from protruding out of the recessed groove 301 and affecting the use of the BDU 10. In this embodiment, the heat dissipation module 4 is installed on the bottom plate 11 of the housing 1, and the heat dissipation module 4 is directly opposite and heat-transferringly connected to the busbar 3. By recessing the locking member 22 in the recessed groove 301, the surface of the busbar 3 facing the heat dissipation module 4 can be kept flat, thereby allowing the busbar 3 and the heat dissipation module 4 to be in close contact and ensuring heat dissipation efficiency.

[0065] The locking component 22 is a locking bolt. The connecting part 210 has a threaded hole 2101, which is directly opposite to the connecting through hole 302 and the first clearance hole 112. The threaded part of the locking bolt is threaded into the threaded hole 2101 through the connecting through hole 302 and the first clearance hole 112. At the same time, the end cap of the locking bolt is recessed in the countersunk groove 301, so that the locking bolt fixes the busbar 3 and the relay contact 2111, thereby achieving a stable locking and fixing effect between the relay 211 and the busbar 3. By selecting a locking bolt, the reliability of the connection between the relay 211 and the busbar 3 can be ensured, and the relay 211 can be disassembled and installed on the busbar 3 by turning the locking bolt, thus facilitating the maintenance and replacement of the relay 211.

[0066] The heat dissipation module 4 includes a liquid cooling plate 41 and a heat-conducting layer. The liquid cooling plate 41 is positioned directly opposite the heat dissipation port 1111. The heat-conducting layer is tightly attached between the busbar 3 and the liquid cooling plate 41 so that the liquid cooling plate 41 can be connected to the busbar 3 through heat transfer via the heat-conducting layer. And / or, the heat-conducting layer is a structural adhesive curing layer. The heat dissipation port 1111 has an annular adhesive-blocking edge 113 protruding from the periphery of the opening end facing the liquid cooling plate 41. The annular adhesive-blocking edge 113 surrounds the busbar 3 to form a filling space 1131, and the filling space 1131 is filled with a structural adhesive curing layer.

[0067] In this embodiment, the heat dissipation module 4 includes a liquid cooling plate 41 and a heat-conducting layer. The liquid cooling plate 41 is positioned directly opposite the heat dissipation port 1111, and the heat-conducting layer is tightly bonded between the busbar 3 and the liquid cooling plate 41, allowing the liquid cooling plate 41 to be connected to the busbar 3 via heat transfer through the heat-conducting layer. By using the heat-conducting layer, the heat transfer path of the relay 211 is optimized to relay contact 2111 - busbar 3 - heat-conducting layer - liquid cooling plate 41. The heat generated by the relay contact 2111 during operation is absorbed by the busbar 3, and then effectively transferred to the liquid cooling plate 41 via the heat-conducting layer. The liquid cooling medium within the liquid cooling plate 41 then carries the heat away, thereby ensuring the cooling effect of the heat dissipation module 4 on the busbar 3. In addition, the thermal conductive layer allows the busbar 3 and the liquid cooling plate 41 to be spatially isolated, preventing the busbar 3 from being directly attached to the liquid cooling plate 41. This way, when the insulating varnish of the liquid cooling plate 41 is damaged, causing the insulation of the liquid cooling plate 41 to fail, the busbar 3 will not directly contact the liquid cooling plate 41, thus eliminating the risk of leakage.

[0068] Considering that the thicker the thermal conductive layer, the worse the thermal conductivity, this application specifies that the minimum thickness of the thermal conductive layer is 1 mm. In this embodiment, the thickness of the thermal conductive layer is set to 1.7 mm.

[0069] The thermally conductive layer is a structural adhesive curing layer formed by the solidification of thermally conductive gel in the area of ​​busbar 3. By using thermally conductive gel to form the thermally conductive layer, the thermally conductive layer has good thermal conductivity and adhesion, ensuring a tight connection between the thermally conductive layer and busbar 3 and liquid cooling plate 41, and effectively reducing the risk of poor contact caused by vibration or temperature changes, thereby improving the stability and reliability of the heat dissipation module 4.

[0070] Referring to Figure 11, an annular adhesive-blocking edge 113 protrudes from the circumference of the opening end of the heat dissipation vent 1111 facing the liquid cooling plate 41. The annular adhesive-blocking edge 113 forms a filling space 1131 around the busbar 3. Thermally conductive gel fills the filling space 1131, forming a uniform thermally conductive layer and effectively preventing the thermally conductive gel from overflowing. The height of the annular adhesive-blocking edge 113 (from the plane of the busbar 3 to the adhesive surface), combined with the tolerance of the busbar 3 (tolerance of the base plate 11 ± 0.2 mm + flatness of the busbar 3 0.5 mm), needs to be higher than the busbar 3 to meet the thickness requirements of the formed thermally conductive layer. In this embodiment, the height of the annular adhesive-blocking edge 113 is equal to the thickness of the thermally conductive layer, i.e., 1.7 mm.

[0071] For example, based on the superior heat dissipation performance of the BDU 10 in this application, the specifications of the relays 211, main fuses 212, and busbars 3 inside the BDU module can be reduced. For instance, a 250A relay 211 can be used instead of a 600A relay 211, a 550A main fuse 212 can be used instead of a 1200A main fuse 212, and a 30*2mm² busbar 3 can be used instead of a 40*3mm² busbar 3. That is, the BDU 10 proposed in this application can achieve the use of reduced specifications for the internal relays 211, main fuses 212, and busbars 3, thereby reducing production costs, reducing the size of internal components, and ensuring structural strength while also allowing for a reasonable layout of internal components.

[0072] In this embodiment, a BDU interface is provided on the periphery of the housing 1. The BDU interface is a plug-in window that is opened on the side wall panel 12 and exposes the end of the corresponding busbar 3. The bottom of the plug-in window forms a fixing part for the busbar 3, and one end of the busbar 3 extends and is fixed to the bottom of the plug-in window, thereby forming different BDU interfaces at different plug-in windows for different busbars 3.

[0073] In this embodiment, referring to Figures 12 and 13, the BDU interface includes a BDU positive input interface 141, a BDU positive output interface 142, a BDU negative input interface 143, and a BDU negative output interface 144. The relay 211 includes a main positive relay 2112 and a main negative relay 2113. The busbar 3 includes a first copper busbar 31, a second copper busbar 32, a third copper busbar 33, and a fourth copper busbar 34. One conductive support post 2121 on one side of the main fuse 212 is connected to the BDU positive input interface 141; one end of the first copper busbar 31 is connected to the conductive support post 2121 on the other side of the main fuse 212, and the other end of the first copper busbar 31 is connected to one end of the main positive relay 2112; one end of the second copper busbar 32... One end of the first copper busbar 32 is connected to the other end of the main positive relay 2112, and the other end of the second copper busbar 32 extends to connect to the positive output interface 142 of the BDU; one end of the third copper busbar 33 is connected to the negative input interface 143 of the BDU, and the other end of the third copper busbar 33 is connected to one end of the main negative relay 2113; one end of the fourth copper busbar 34 is connected to the other end of the main negative relay 2113, and the other end of the fourth copper busbar 34 extends to connect to the negative output interface 144 of the BDU, thereby enabling the cells in the battery pack to make conductive connections with external electrical equipment through the BDU 10, and when a fault occurs, the main fuse 212 can quickly disconnect the circuit to protect the cells and equipment.

[0074] Referring to Figure 12, the current device also includes a precharge relay 213, a precharge resistor 214, a current sensor 215, an NTC (negative temperature coefficient thermistor) 216, an HMU (high voltage acquisition unit) 217, and a DC-DC (voltage converter) fuse 218 located in the mounting cavity.

[0075] The precharge relay 213 and the precharge resistor 214 are connected in series and then in parallel with the main positive relay 2112. The precharge process is provided through the precharge resistor 214 and the precharge relay 213. The precharge relay 213 and the precharge resistor 214 form a precharge circuit. The precharge relay 213 can control the opening and closing of the precharge circuit, while the precharge resistor 214 plays a current limiting role.

[0076] One end of the current sensor 215 is connected in series with the main negative relay 2113, and the other end is electrically connected to the negative terminal of the module cell, and is set to the current value in the test circuit. This current sensor 215 is a Hall sensor.

[0077] The NTC216 is located inside the mounting cavity and connected in series with the main negative relay 2113. It is configured to collect the highest temperature range of the BDU and use this as a basis for judging whether the liquid cooling heat dissipation has failed.

[0078] One end of the HMU217 is connected in series with the main negative relay 2113, and the other end is connected to the negative output interface 144 of the BDU. It is configured to monitor the voltage of the BDU 10 in real time to ensure the safe operation of the high-voltage circuit inside the BDU 10.

[0079] The DC-DC fuse 218 is connected to the positive output interface 142 of the BDU and serves as an overcurrent protection device. When an abnormal voltage or temperature occurs at the positive output interface 142 of the BDU, the DC-DC fuse 218 will cut off the current to prevent damage to the module cells and BDU 10.

[0080] The BDU interface provided in this embodiment also includes a fast charging interface, which includes a fast charging positive interface 1451 and a fast charging negative interface 1452; the relay 211 also includes a fast charging positive relay 2114 and a fast charging negative relay 2115; the busbar 3 also includes a fifth copper busbar 35 and a sixth copper busbar 36. The fast-charging positive relay 2114 is connected in parallel to one side of the main positive relay 2112. One end of the fast-charging positive relay 2114 and the other end of the main positive relay 2112 are both connected to the second copper busbar 32. The other end of the fast-charging positive relay 2114 is connected to one end of the fifth copper busbar 35. The other end of the fifth copper busbar 35 is connected to the fast-charging positive interface 1451. The fast-charging negative relay 2115 is connected in parallel to one side of the main negative relay 2113. The fast-charging negative relay 2115 and the main negative relay 2113 are both connected to one end of the fourth copper busbar 34. One end of the sixth copper busbar 36 is connected to the fast-charging negative interface 1452. The other end of the sixth copper busbar 36 is connected to the fast-charging negative relay 2115. This allows the high-voltage electricity from the charging element to be directly connected to the battery pack through the BDU 10, achieving the purpose of high-current fast charging.

[0081] Optionally, the BDU interface provided in this embodiment also includes a range extender interface, which includes a positive range extender interface 1461 and a negative range extender interface 1462. The positive range extender interface 1461 is connected to the positive terminal of the power generation device (e.g., a generator in a vehicle), and the negative range extender interface 1462 is connected to the negative terminal of the power generation device. When the power generation device is connected to the battery pack through the above connection method, the module cells can be powered by the selected power generation device, reducing the situation where the vehicle cannot continue to drive when the module cells are out of power and there is no charging pile nearby, thereby improving the range of the electrical equipment.

[0082] The BDU 10 provided in this embodiment is equipped with both a fast charging interface and a range extender interface to suit range-extended / plug-in hybrid vehicles. This allows users to choose between low-cost fast charging or pre-extended range, balancing charging speed and enhanced range. Different vehicle types have different needs. For example, for battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs), only a fast charging interface needs to be provided on the BDU 10. However, for range-extended electric vehicles (REEVs), range extension is the primary means of extending range, and fast charging is not a necessary requirement for this type of vehicle. Therefore, only a range extender interface needs to be provided on the BDU 10.

[0083] To achieve the connection between the busbar 3 and the BDU interface, in this embodiment, the base plate 11 is also provided with a second clearance hole 114, and at least two mounting grooves 111 are provided, for example, six mounting grooves 111 are provided, corresponding to the first copper busbar 31, the second copper busbar 32, the third copper busbar 33, the fourth copper busbar 34, the fifth copper busbar 35 and the sixth copper busbar 36 respectively, wherein at least one mounting groove 111 is correspondingly provided in the second clearance hole 114; the busbar 3 includes a first busbar 310 and a second busbar 320, the first busbar 310 is integrally formed in the mounting groove 111, and a connecting through hole 302 is provided on the first busbar 310, the second busbar 320 is bent, one end of the second busbar 320 is connected to the first busbar 310 through the second clearance hole 114, and the other end of the second busbar 320 is connected to the BDU interface. The first busbar 310 is flat and integrally connected to the base plate 11 by being embedded in the mounting groove 111. The second busbar 320 is bent. One end of the second busbar 320 can be connected to the first busbar 310 by bolts through the second clearance hole 114, and the other end of the second busbar 320 is bent and extended to the plug-in window and connected to the BDU interface. By designing the busbar 3 as a split structure, the busbar 3 can simultaneously simplify the fixed installation of electrical components 2 such as relays 211 and fuses, and extend to the plug-in window to connect to the BDU interface. Moreover, by first integrally injection molding the first busbar 310 and the base plate 11, and then fixing the second busbar 320 to the first busbar 310 by bolts, the operation difficulty of fixing the busbar 3 to the base plate 11 can be effectively reduced, thereby ensuring high assembly efficiency.

[0084] For example, in this embodiment, the second copper busbar 32, the fourth copper busbar 34, the fifth copper busbar 35, and the sixth copper busbar 36 are all split structures, and each includes the aforementioned first busbar 310 and second busbar 320. The first busbar 310 of the second copper busbar 32 is T-shaped, with one end connected to the other end of the main positive relay 2112. The remaining two ends of the second copper busbar 32 are each provided with a second busbar 320, one of which is connected to the BDU positive output interface 142, and the other is connected to the range extender positive interface 1461.

[0085] The first busbar 310 of the fourth copper busbar 34 is L-shaped. One extension of the first busbar 310 is connected to the other end of the main negative relay 2113. A second busbar 320 is provided at each end of the other extension of the first busbar 310. One second busbar 320 is configured to be connected to the negative output interface 144 of the BDU, and the other second busbar 320 is configured to be connected to the range extender negative interface 1462.

[0086] The first busbar 310 of the fifth copper busbar 35 is in the shape of a "I". One end of the first busbar 310 is connected to the other end of the fast charging positive relay 2114, and the other end of the first busbar 310 is connected to the second busbar 320. The second busbar 320 is configured to be connected to the fast charging positive interface 1451.

[0087] The first busbar 310 of the sixth copper busbar 36 is L-shaped, and one extension of the first busbar 310 is connected to the fast charging negative relay 2115. The other extension of the first busbar 310 is connected to the second busbar 320, which is configured to be connected to the fast charging negative interface 1452.

[0088] Another embodiment of this application provides a battery pack, which includes module cells 50 and the BDU 10 described in the above embodiment, with the module cells 50 electrically connected to the BDU 10. By using the BDU 10, not only can the heat dissipation module 4 heat up electrical components such as the relay 211 and fuses, as well as the busbar 3, but the heat dissipation effect of the electrical components 2 and busbar 3 can be enhanced, reducing the size of the electrical components 2 and busbar 3 and lowering the cost of use; moreover, by integrally molding the busbar 3 onto the bottom plate 11 of the housing 1, the layout of the busbar 3 can be optimized, enhancing the safety and stability of the busbar 3 in use. At the same time, it can save internal space in the housing 1, simplify the layout design of the electrical components 2, reduce wiring and production difficulty, thereby effectively improving the production efficiency and safety and stability of the battery pack.

[0089] The above-mentioned battery pack is a cell-to-pack (CTP) type battery pack. In other parallel embodiments, when the battery pack is a modular battery pack, the battery pack also includes an integrated housing. The BDU 10 and the module cells are all installed in the integrated housing to complete the assembly of the battery pack.

[0090] This application provides a BDU and a battery pack, which optimizes the layout design of the liquid cooling module in the BDU, improves the stability of the copper busbar, reduces the difficulty of copper busbar installation and layout between the copper busbar and multiple electrical components, ensures the efficient production and stable use of the BDU, thereby improving the production efficiency and quality of the battery pack.

[0091] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

Claims

1. A battery pack circuit breaker unit, comprising: The shell (1) includes a base plate (11); Electrical components (2) are installed inside the housing (1) and disposed on the base plate (11); Busbar (3) is disposed on the base plate (11) and electrically connected to the electrical component (2), and the busbar (3) and the base plate (11) are integrally formed; The heat dissipation module (4) is disposed on the base plate (11) and is heat-transfer connected to the busbar (3).

2. The battery pack circuit breaker unit according to claim 1, wherein, The electrical component (2) includes a current device and a locking member (22). The current device is electrically connected to the bus (3) and the current device is provided with a connection part (210). The locking member (22) is configured to lock the connection part (210) and the bus (3) so that the current device is locked onto the bus (3).

3. The battery pack circuit breaker unit according to claim 2, wherein, The base plate (11) is provided with an embedding groove (111) and a first clearance hole (112). The busbar (3) is integrally formed and disposed in the embedding groove (111). The embedding groove (111) is provided with a heat dissipation port (1111) on the side facing the heat dissipation module (4). The busbar (3) is connected to the heat dissipation module (4) through the heat dissipation port (1111). The first clearance hole (112) is connected to the embedding groove (111). The first clearance hole (112) is correspondingly disposed in the connecting part (210). The locking member (22) passes through the busbar (3) and the first clearance hole (112) and is locked and connected to the connecting part (210).

4. The battery pack circuit breaker unit according to claim 3, wherein, The busbar (3) has a recessed groove (301) on the side facing the heat dissipation module (4). A connecting through hole (302) is opened at the bottom of the recessed groove (301). The connecting through hole (302) is directly opposite to the first clearance hole (112). One end of the locking member (22) facing the connecting part (210) passes through the connecting through hole (302) and the first clearance hole (112) and is locked to the connecting part (210). The other end of the locking member (22) facing the heat dissipation module (4) is sunk in the recessed groove (301).

5. The battery pack circuit breaker unit according to claim 4, wherein, The locking component (22) is a locking bolt. The connecting part (210) is provided with a threaded hole (2101). The threaded hole (2101) is directly opposite to the connecting through hole (302) and the first clearance hole (112). The threaded part of the locking bolt passes through the connecting through hole (302) and the first clearance hole (112) and is threadedly connected to the threaded hole (2101). The end cap of the locking bolt is recessed in the groove (301).

6. The battery pack circuit breaker unit according to claim 3, wherein, The heat dissipation module (4) includes a liquid cooling plate (41) and a heat-conducting layer. The liquid cooling plate (41) is positioned directly opposite the heat dissipation port (1111). The heat-conducting layer is tightly bonded between the busbar (3) and the liquid cooling plate (41) so that the liquid cooling plate (41) is connected to the busbar (3) through the heat-conducting layer; or, The thermally conductive layer is a structural adhesive curing layer. The heat dissipation port (1111) facing the liquid cooling plate (41) has an annular adhesive-blocking edge (113) protruding on the periphery of the opening end. The annular adhesive-blocking edge (113) surrounds the busbar (3) to form a filling space (1131). The filling space (1131) is filled with the structural adhesive curing layer. The heat-conducting layer is tightly attached between the busbar (3) and the liquid cooling plate (41) so that the liquid cooling plate (41) is connected to the busbar (3) through the heat-conducting layer. The heat-conducting layer is a structural adhesive curing layer. The heat dissipation port (1111) has an annular adhesive-blocking edge (113) protruding on the periphery of the opening end facing the liquid cooling plate (41). The annular adhesive-blocking edge (113) surrounds the busbar (3) to form a filling space (1131). The filling space (1131) is filled with the structural adhesive curing layer.

7. The battery pack circuit breaker unit according to claim 4, wherein, The current device includes a relay (211), the relay (211) is provided with relay contacts (2111), and the relay contacts (2111) are configured as the connection part (210); The current device also includes a main fuse (212), and a conductive support post (2121) is connected to the outside of the main fuse (212), and the conductive support post (2121) is configured as the connection part (210).

8. The battery pack circuit breaker unit according to claim 7, wherein, The housing (1) is provided with a BDU interface on its periphery, the BDU interface including a BDU positive input interface (141), a BDU positive output interface (142), a BDU negative input interface (143), and a BDU negative output interface (144); the relay (211) includes a main positive relay (2112) and a main negative relay (2113); the busbar (3) includes a first copper busbar (31), a second copper busbar (32), a third copper busbar (33), and a fourth copper busbar (34), wherein: The conductive support post (2121) on one side of the main fuse (212) is connected to the positive input interface (141) of the BDU; One end of the first copper busbar (31) is connected to the conductive support column (2121) on the other side of the main fuse (212), and the other end of the first copper busbar (31) is connected to one end of the main positive relay (2112). One end of the second copper busbar (32) is connected to the other end of the main positive relay (2112), and the other end of the second copper busbar (32) extends to be connected to the positive output interface (142) of the BDU; One end of the third copper busbar (33) is connected to the negative input interface (143) of the BDU, and the other end of the third copper busbar (33) is connected to one end of the main negative relay (2113); One end of the fourth copper busbar (34) is connected to the other end of the main negative relay (2113), and the other end of the fourth copper busbar (34) extends to be connected to the negative output interface (144) of the BDU.

9. The battery pack circuit breaker unit according to claim 7, wherein, The housing (1) is provided with a BDU interface on its periphery, the bottom plate (11) is provided with a second clearance hole (114), and at least two mounting grooves (111) are provided, with at least one mounting groove (111) corresponding to the second clearance hole (114). The busbar (3) includes a first busbar (310) and a second busbar (320). The first busbar (310) is integrally formed in the mounting groove (111) and has the connecting through hole (302) formed on it. The second busbar (320) is bent. One end of the second busbar (320) is connected to the first busbar (310) through the second clearance hole (114), and the other end of the second busbar (320) is connected to the BDU interface.

10. A battery pack comprising a module cell (50) and a BDU (10) according to any one of claims 1 to 9, wherein the module cell (50) is electrically connected to the BDU (10).

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