BDU device and battery pack

Abstract

To provide a BDU device and a battery pack.SOLUTION: The present application discloses a BDU device and a battery pack. The BDU device includes a housing, a heating element and a heat conductive plate. One end of the housing is provided with an opening. The heating element is disposed in the housing. The heat conductive plate is provided with a first side and a second side opposite to each other, the first side is located in the opening and is thermally coupled with the heating element, and the second side is located outside the housing.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This application claims priority based on a Chinese patent application with application number 202323671457.9 filed with the China National Intellectual Property Administration on December 31, 2023, and incorporates by reference all of the content of the Chinese patent application herein.

[0002] This application relates to the field of battery technology, and more specifically to BDU devices and battery packs.

Background Art

[0003] In related technologies, in order to improve the reliability of battery packs, a BDU (Battery Disconnect Unit) device is usually installed in the battery pack. The BDU device includes a housing and a large number of electronic devices that generate a lot of heat, such as conductive bars, fuses, and relays, which are installed inside the housing. Due to the space limitation of the battery pack, the components in the battery pack are arranged compactly. Therefore, the current BDU device mainly uses natural cooling to dissipate heat. This heat dissipation method is inefficient, so the BDU device will be placed in a high-temperature environment for a long time, resulting in a decrease in the reliability of the BDU device.

Summary of the Invention

Problems to be Solved by the Invention

[0004] This application provides a BDU device and a battery pack for solving the above technical problems.

Means for Solving the Problems

[0005] According to a first aspect, an embodiment of this application provides a BDU device, which includes a housing, a heating element, and a heat conduction plate. An opening is provided at one end of the housing. The heating element is arranged inside the housing. The heat conduction plate has a first side and a second side on opposite sides. The first side is located inside the opening and is thermally coupled to the heating element. The second side is located outside the housing.

[0006] According to the second aspect, the embodiment of the present application provides a battery pack, which includes a box and the aforementioned BDU device. The box has a receiving cavity, the BDU device is disposed in the receiving cavity, and the second side is thermally coupled to the cavity wall of the receiving cavity.

Advantages of the Invention

[0007] The beneficial effects of the present application are as follows. The BDU device provided in the present application can dissipate heat through the heat conduction plate by thermally coupling the heat conduction plate with the heat generating body of the BDU device. Thereby, the heat dissipation efficiency of the BDU device is improved, the current capacity of the BDU device is improved, and finally the reliability of the BDU device is improved.

[0008] The battery pack provided in the present application can improve the reliability of the electrical components of the battery pack and the reliability of the battery pack by using the aforementioned BDU device.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0010] In the description of this application, unless otherwise explicitly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it may be a fixed connection, a removable connection, or an integrated connection, or it may be a mechanical connection or an electrical connection, or it may be a direct connection or an indirect connection through an intermediate medium, or it may be an internal connection between two elements or an interaction between two elements. A person skilled in the art will understand the specific meaning of the above terms in this application based on specific situations.

[0011] In this application, unless otherwise explicitly defined and limited, the first feature that is "above" or "below" the second feature may include direct contact between the first feature and the second feature, or may include contact between the first feature and the second feature through another feature between them rather than direct contact. Further, the fact that the first feature is "above", "above", and "upper" of the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The fact that the first feature is "below", "below", and "lower" of the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0012] In addition, in the description of this embodiment, terms such as "above", "below", and "right" are based on the directions and positional relationships shown in the drawings, for the convenience of description and simplification of operation, and do not intend to indicate or imply that the device or element mentioned must have a specific direction and must be constructed and operated in a specific direction. Therefore, it should not be construed as limiting this application. Also, the terms "first" and "second" are used only for the purpose of description and have no special meaning.

[0013] Referring to FIG. 1, FIG. 1 is a schematic structural diagram of the BDU device 001 provided in the embodiment of the present application. The embodiment of the present application provides a BDU device 001, and this BDU device 001 includes a housing 011, a heating element 012, and a heat conduction plate 013. An opening 111 is provided at one end of the housing 011. The heating element 012 is disposed inside the housing 011. The heat conduction plate 013 has a first side and a second side on opposite sides of each other. The first side is located within the opening 111 and is thermally coupled to the heating element 012. The second side is located outside the housing 011.

[0014] When the BDU device 001 is applied to a battery pack, it can be understood that the BDU device 001 is installed within the box of the battery pack. Specifically, the BDU device 001 is attached to the bottom protection plate of the battery pack, the first side is in close contact with the heating element 012, and the second side is in close contact with the bottom protection plate. The heat conduction plate 013 conducts the heat from the heating element 012 to the bottom protection plate, and the outer surface of the bottom protection plate is exposed to the atmospheric environment for heat dissipation. Here, examples of the heating element 012 include, but are not limited to, a conductive bar 121, a relay, a fuse, etc. As the heat conduction plate 013, a silicon thermal conduction pad, a rubber heat conduction plate, a metal plate coated with an insulating layer, etc. can be used.

[0015] In this embodiment, by thermally coupling the heat conduction plate 013 to the heating element 012 of the BDU device 001, the BDU device 001 can dissipate heat through the heat conduction plate 013, thereby improving the heat dissipation efficiency of the BDU device 001, thereby improving the current capacity of the BDU device 001, and ultimately improving the reliability of the BDU device 001. On the other hand, by disposing the second side outside the housing 011, a gap is formed between the side close to the inner wall of the box of the housing 011 and the box, avoiding contact between the housing 011 and the box, thereby avoiding the situation where the mounting and locking force of the BDU device 001 is too large and the housing 011 presses and damages the box.

[0016] Referring to FIG. 2, FIG. 2 shows an embodiment. The heating element 012 includes a conductive bar 121. Both ends of the conductive bar 121 are connection ends. At least a part of the conductive bar 121 excluding the connection ends protrudes toward the heat conduction plate 013 and abuts against the first side. As shown in FIG. 3, FIG. 3 is a schematic diagram of the abutment between the conductive bar 121 and the heat conduction plate 013 provided in the embodiment of the present application.

[0017] It can be understood that the conductive bar 121 is used to electrically connect some electrical components of the BDU device 001, such as the electrical connection between the high-voltage input port and the high-voltage output port of the BDU device 001. Exemplarily, the conductive bar 12 is a copper bar.

[0018] In this embodiment, by protruding the middle part of the conductive bar 121 toward the heat conduction plate 013 and abutting it against the first side, the conductive bar 121 and the heat conduction plate 013 can be thermally coupled. As a result, the heat conduction plate 013 can dissipate heat from the conductive bar 121, and the conductive bar 121 can achieve the electrical connection between related components.

[0019] In one embodiment, the heat conduction plate 013 has elasticity. For example, the heat conduction plate 013 is a silicon thermal conduction pad, and its thermal conductivity is 3 W / m·K or more.

[0020] It can be understood that the BDU device 001 is removably fixed to the box via bolts 031. Also, when the BDU device 001 is installed in the box, the heat conduction plate 013 is located between the heating element 012 and the wall of the box and is under pressure.

[0021] In this embodiment, by using the elastic heat conduction plate 013, the heat conduction plate 013 can be compressed when the BDU device 001 is installed. In this way, a pre-tightening force can be formed on the heat conduction plate 013 to prevent the loosening of the bolt 031 that fixes the BDU device 001 to the box, thereby improving the installation stability of the BDU device 001. On the other hand, the heat conduction plate 013 can be pushed in to make it fit more closely with the heating element 012 and the box, thereby improving the heat dissipation efficiency of the BDU device 001.

[0022] Referring to FIG. 4, FIG. 4 is an enlarged view of part A in FIG. 1. In one embodiment, the distance between the second side and the outer surface of the housing 011 is d1, which satisfies 1 mm ≤ d1 ≤ 4 mm. It can be understood that d1 includes, but is not limited to, 1 mm, 1.5 mm, 1.8 mm, 2 mm, 2.6 mm, 3 mm, 3.3 mm, 3.8 mm, 4 mm.

[0023] In this embodiment, by restricting the distance between the second side and the housing 011, it is possible to avoid the situation where the distance between the second side and the housing 011 is too small and the housing 011 contacts the box, thereby avoiding the situation where the mounting and locking force of the BDU device 001 is too large and the housing 011 presses the box and causes damage. On the other hand, it is possible to avoid the situation where the distance between the second side and the housing 011 is too large and the heat conduction performance of the heat conduction plate 013 decreases.

[0024] Referring to FIG. 4, in one embodiment, the heat conduction plate 013 includes a heat conduction plate 013 body and an insulating film 132. The heat conduction plate 013 body has a first side and a second side, and the insulating film 132 covers at least the first side or the second side. Exemplarily, the insulating film 132 completely covers the surface of the heat conduction plate 013. Here, the main body of the heat conduction plate 013 is a silicon heat conduction pad. Examples of the insulating film 132 include, but are not limited to, a PET insulating film 132 and a PC insulating film 132. The thermal conductivity of the PET insulating film 132 is higher than that of the PC insulating film 132. Therefore, optionally, the insulating film 132 is a PET insulating film 132.

[0025] In this embodiment, by covering the first side or the second side with the insulating film 132, the insulation between the heating element 012 and the battery box is improved, the normal operation of the BDU device 001 is guaranteed, and the reliability of the BDU device 001 is improved.

[0026] Referring to FIG. 4, in one embodiment, the thickness of the insulating film 132 is d2, satisfying 0.1 mm ≤ d2 ≤ 0.2 mm. It can be understood that d2 includes, but is not limited to, 0.1 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.17 mm, 0.18 mm, 0.19 mm, and 0.2 mm.

[0027] In this embodiment, by limiting the thickness of the insulating film 132, it is possible to avoid the insulating film 132 from being damaged due to too thin a thickness, thereby ensuring the insulation between the heating element 012 and the box. On the other hand, it is possible to avoid the thermal conductivity performance of the heat conduction plate 013 from decreasing due to too thick a thickness of the insulating film 132.

[0028] In one embodiment, the heat conduction plate 013 engages with the opening 111. It can be understood that the opening 111 is press-fitted with the heat conduction plate 013 to realize the engagement between the heat conduction plate 013 and the opening 111. In this embodiment, by engaging the heat conduction plate 013 with the opening 111, the connection stability between the heat conduction plate 013 and the housing 011 is improved, and it is possible to prevent the heat conduction plate 013 from coming out of the opening 111 of the housing 011. Thereby, the convenience of installation of the BDU device 001 can be improved.

[0029] Referring to FIG. 5, FIG. 5 is a schematic structural diagram of the BDU device 001 installed in the box provided by the embodiment of the present application. Accordingly, the embodiment of the present application further provides a battery pack, which includes a box and the aforementioned BDU device 001. The box has a receiving cavity. The BDU device 001 is disposed in the receiving cavity. The second side is thermally coupled to the cavity wall of the receiving cavity. Specifically, the second side is thermally coupled to the bottom protection plate 021.

[0030] It can be understood that the BDU device 001 is removably fixed in the receiving cavity through a fixture. The fixture includes a bolt 031, a hanging lug is provided on the outer wall of the housing 011, a bolt 031 through-hole is provided on the hanging lug, the end of the rod of the bolt 031 passes through the bolt 031 through-hole and is screwed into the box, the head of the bolt 031 abuts against the hanging lug, and the axial direction of the bolt 031 is perpendicular to the heat conduction plate 013, whereby the heating element 012, the heat conduction plate 013, and the bottom protection plate 021 are pushed in sequence.

[0031] In this embodiment, by using the above-mentioned BDU device 001, the reliability of the electrical components of the battery pack can be improved, and the reliability of the battery pack can be improved.

[0032] In one embodiment, the heat conduction plate 013 is in a compressed state. Specifically, the cavity wall of the receiving cavity that is thermally coupled to the second side is the first cavity wall, the distance between the first cavity wall and the housing 011 is D, as shown in FIG. 6, FIG. 6 is an enlarged view of part B of FIG. 5. In the original state of the heat conduction plate 013, the distance between the second side and the housing 011 is d1, and D < d1 is satisfied.

[0033] It can be understood that the heat conduction plate 013 has elasticity. The original state of the heat conduction plate 013 means that the heat conduction plate 013 is not deformed by an external force. In the original state, the heat conduction plate 013 is in a natural shape, and the heat conduction plate 013 is not stretched, compressed, or distorted.

[0034] Exemplarily, 0.4 mm ≤ d1 - D ≤ 0.7 mm. Specifically, the difference between D and d1 includes, but is not limited to, 0.4 mm, 0.5 mm, 0.6 mm, and 0.7 mm. If this difference is too large, it means that the thickness of the heat conduction plate 013 is thick. When the thickness of the heat conduction plate 013 is too large, the heat conduction of the heat conduction plate 013 becomes poor. If this difference is too small, it can be understood that when the BDU device 001 is installed, the housing 011 is likely to contact the box and be damaged.

[0035] In this embodiment, due to the above limitations, the heat conduction plate 013 is in a compressed state. In this way, a pre-tightening force can be formed on the heat conduction plate 013 to prevent the bolt 031 that fixes the BDU device 001 to the box from loosening, thereby improving the installation stability of the BDU device 001. On the other hand, the heat conduction plate 013 can be pushed in to make it fit more closely with the heating element 012 and the box, improving the heat dissipation efficiency of the BDU device 001.

Description of Reference Numerals

[0036] 001: BDU device, 011: housing, 111: opening, 112: lug plate, 012: heating element, 121: conductive bar, 013: heat conduction plate, 131: heat conduction plate body, 132: insulating film, 021: bottom protection plate, 031: bolt.

Claims

1. A BDU device, including a housing, a heating element, and a heat conduction plate, wherein an opening is provided at one end of the housing, the heating element is disposed within the housing, the heat conduction plate has a first side and a second side on opposite sides of each other, the first side is located within the opening and is thermally coupled to the heating element, and the second side is located outside the housing BDU device.

2. The heating element includes a conductive bar, both ends of the conductive bar are connection ends, and at least a part of the conductive bar excluding the connection ends projects toward the heat conduction plate and abuts against the first side The BDU device according to Claim 1.

3. The heat conduction plate has elasticity and is a silicon heat conduction pad or a rubber heat conduction plate The BDU device according to Claim 1.

4. The distance between the second side and the outer surface of the housing is d １ and 1 mm ≤ d １ ≤ 4 mm is satisfied The BDU device according to Claim 1.

5. The heat conduction plate includes a heat conduction plate body and an insulating film, the heat conduction plate body has the first side and the second side, and the insulating film covers at least the first side or the second side The BDU device according to Claim 1.

6. The thickness of the insulating film is d ２ where 0.1 mm ≤ d ２ ≤ 0.2 mm The BDU device according to Claim 5.

7. The insulating film is a PET insulating film The BDU device according to Claim 5.

8. The heat conduction plate engages with the opening The BDU device according to Claim 1.

9. A battery pack, including a box and the BDU device according to any one of Claims 1 to 8, the box has a receiving cavity, the BDU device is removably fixed within the receiving cavity via a fixture, and the second side is thermally coupled to the cavity wall of the receiving cavity Battery pack.

10. The heat conduction plate is in a compressed state The battery pack according to Claim 9.

11. The cavity wall thermally coupled to the second side of the receiving cavity is the first cavity wall, the distance between the first cavity wall and the housing is D, and in the original state of the heat conduction plate, the distance between the second side and the housing is d １ where D < d １ is satisfied The battery pack according to Claim 10.

12. 0.4 mm ≤ d １ -D ≤ 0.7 mm The battery pack according to Claim 11.

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