Battery pack

Abstract

Battery pack, characterized in that it comprises a box body, a battery group and a battery pack separation unit, wherein the box body comprises a base plate and a box frame, the box frame being attached to the base plate and enclosing a receiving space of the box body; wherein a partition support is provided inside the box body, the partition support dividing the receiving space into a battery compartment and an electrical compartment; wherein the battery group is provided within the battery compartment, wherein the battery pack separation unit is provided within the electrical compartment; wherein the battery pack separation unit comprises a housing body, a printed circuit board and an electronic element connected to the printed circuit board, wherein the printed circuit board is provided inside the housing body, and wherein the electronic element is arranged on plate surfaces on both sides of the printed circuit board; wherein the electronic element comprises a positive main relay and a negative main relay, wherein the battery pack further comprises a copper row, wherein the copper row is connected to the positive main relay and the negative main relay and is arranged on the same side of the circuit board as the positive main relay and the negative main relay.

Description

Technical field

[0001] The present application relates to the technical field of new energy batteries, in particular a battery pack. Technical background

[0002] The battery disconnect unit (BDU) is a crucial component of new energy vehicles, used for charging and discharging control, overload protection of the high-voltage electrical system, and other functions. Various types of relays are essential elements within the BDU and ensure its proper operation.

[0003] In related technologies, the electrical components in the BDU are typically located on the same side of the circuit board, resulting in a more compact and regular overall structure. Due to the BDU's configuration, the battery pack's electrical compartment must provide sufficient space, which directly impacts the battery's energy density. Content of the invention

[0004] To solve the above technical problems, the present invention provides a battery pack that can effectively reduce the space occupied by the BDU in the battery pack and improve the energy density of the battery through solution optimization.

[0005] The present invention provides a battery pack comprising a box body, a battery group, and a battery pack separation unit, wherein the box body comprises a base plate and a box frame, the box frame being attached to the base plate and enclosing a receiving space of the box body; wherein a partition support is provided inside the box body, the partition support dividing the receiving space into a battery compartment and an electrical compartment; wherein the battery group is provided inside the battery compartment, and the battery pack separation unit is provided inside the electrical compartment; wherein the battery pack separation unit comprises a housing body, a printed circuit board, and an electronic element connected to the printed circuit board, the printed circuit board being provided inside the housing body, and the electronic element being arranged on plate surfaces on both sides of the printed circuit board;wherein the electronic element comprises a positive main relay and a negative main relay, wherein the battery pack further comprises a copper row, the copper row being connected to the positive main relay and the negative main relay and being arranged on the same side of the circuit board as the positive main relay and the negative main relay.

[0006] In comparison to the prior art, the present invention provides an implementation solution for the battery pack. Specifically, the aforementioned electronic elements are arranged on plate surfaces on both sides of the printed circuit board of the battery pack separator unit. Compared to the prior art, in the present solution the electronic elements are arranged on the plate surfaces on both sides of the printed circuit board, thereby reducing the area of ​​the printed circuit board and saving the space occupied by the battery pack separator unit within the battery pack. By applying the present solution, the size of the electronics compartment can be effectively reduced, and a larger portion of the available space within the battery pack housing can be allocated to the side of the battery compartment.As a result, the volume of the battery pack can be increased accordingly, which is a good technical guarantee for the overall improvement of the battery's energy density.

[0007] Furthermore, the electronic components can be flexibly arranged on the upper and lower surfaces of the printed circuit board. This reduces the mutual interference between the electronic components due to their own heat generation and facilitates heat dissipation. It also reduces electromagnetic interference between the electronic components to ensure the effective transmission of control signals. Images Fig. Figure 1 is a schematic representation of the assembly relationship of a box body of a battery pack in an embodiment of the present application; Fig. 2 is an exploded view of the assembly of the in Fig. 1 shown battery pack separation unit; Fig. Figure 3 is a schematic representation of the battery pack separation unit of the battery pack in an embodiment of the present invention; Fig. 4 is a schematic representation of a layout of a plate area on one side of the printed circuit board of the in Fig. 3 shown battery pack separation unit; Fig. Figure 5 is a schematic representation of the layout of the plate area on the other side of the printed circuit board. Fig. 3 shown battery pack separation unit; Fig. Figure 6 is a schematic representation of the layout above the printed circuit board in an embodiment of the present invention; Fig. Figure 7 is a schematic representation of the layout below the printed circuit board in an embodiment of the present invention; Fig. Figure 8 shows a schematic representation of the assembly relationship between the printed circuit board and the BMS main board in an embodiment of the present invention. Reference symbol list:

[0008] Battery pack disconnect unit 10, housing body 1, first housing body 11, second housing body 12, escape recess 13, circuit board 2, heating fuse 31, heating relay 32, pre-charge relay 33; positive main relay 34, negative main relay 35, main fuse 36, pre-charge resistor 37, BMS main board 4, copper row 5, high-voltage sensing connector 6, low-voltage communication connector 7; Box body 20, base plate 21, box frame 22, subdivision support 23, reinforcement support 24. Description of embodiments

[0009] In order to enable the person skilled in the art to better understand the technical solution of the present invention, a detailed description of the present invention follows in conjunction with the attached drawings and specific embodiments.

[0010] Given the increasing demand for range, controlling battery pack size and effectively improving battery energy density have become key research and development priorities in the industry. A typical battery pack housing comprises a battery compartment and an electrical compartment. As in Fig. 1 and Fig. 2 shown, is Fig. 1 a schematic representation of the assembly relationship of a box body of a battery pack in an embodiment of the present application, and Fig. 2 is an exploded view of the assembly of the in Fig. 1 battery pack separation unit shown; To simplify the description, functional components such as a battery group are shown in the Fig. 1 and Fig. Battery compartment 2 is not shown.

[0011] The battery pack comprises a box body 20, a battery group (not shown in the figures) and a battery pack separation unit 10. The box body 20 comprises a base plate 21 and a box frame 22, the box frame 22 being rigidly connected to the base plate 21 to enclose and form a receiving space of the box body 20 in which internal components such as the battery group and the battery pack separation unit 10 are assembled.

[0012] As in the Fig. 1 and Fig. As shown in Figure 2, the box body 20 is provided with a partition carrier 23, which divides the receiving space into a battery compartment A and an electrical compartment B. The battery group is located within battery compartment A, with the battery pack separator 10 located within electrical compartment B;

[0013] As in Fig. 3, Fig. 4 and Fig. As shown in 5, Fig. 3 a schematic representation of the battery pack separation unit of the battery pack in an embodiment of the present invention, Fig. 4 is a schematic representation of a layout of a plate area on one side of the printed circuit board of the in Fig. 3 shown battery pack separation unit, and Fig. Figure 5 is a schematic representation of the layout of the plate area on the other side of the printed circuit board. Fig. 3 shown battery pack separation unit;

[0014] As in Fig. As shown in Figure 3, the battery pack disconnect unit 10 comprises a housing body 1 and a printed circuit board provided in the housing body 1, as well as various electronic components, including, but not limited to, various types of relays and the like. The housing body 1 shown in the figure comprises a first housing body 11 and a second housing body 12, which are connected to each other and constructed to form the housing body 1 in which each component is accommodated.

[0015] In this embodiment, the electronic components are arranged on the circuit board surface on both sides of the printed circuit board 2. In other words, the electrical components connected to the printed circuit board are located above and below the printed circuit board 2. For the sake of simplicity, the first housing body 11 shown in the figure is defined as a lower housing part, and the second housing body 12 is a higher housing part.

[0016] As in Fig. Figure 4 shows a schematic representation of the layout of the electrical elements above the circuit board 2. The circuit board 2 is equipped on its upper surface with electrical elements such as a heating fuse 31, a heating relay 32, and a pre-charging relay 33. As shown in Fig. Figure 5 shows a schematic representation of the layout of the electrical elements below the printed circuit board 2. The printed circuit board 2 is provided on the lower plate surface with a positive main relay 34 and a negative main relay 35, both of which are electrically connected to an output terminal of the battery pack (not shown in the figure), and electrical elements such as a main fuse 36 and a pre-charge resistor 37 are also provided on the lower plate surface of the printed circuit board 2.

[0017] The positive main relay 34 is the main relay for the positive electrode side of the high-voltage system, and the negative main relay 35 is the main relay for the negative electrode side of the high-voltage system. The pre-charge relay 33 is used in the pre-charge circuit as a switch for turning the pre-charge circuit on and off and for overcurrent protection, i.e., for energizing the pre-charge circuit for self-monitoring before the main relay operates. The heater relay 32 is used in the heater circuit as a switch for the heater circuit to turn the heater circuit on and off and for overcurrent protection. The above relays are used as non-manually operated mechanical switching devices with only one rest position, capable of switching on, conducting, and interrupting currents under normal circuit conditions, including overload conditions.

[0018] The pre-charge resistor 37 is a power resistor that initially closes the pre-charge circuit to charge the X-capacitor on the electrical drive side when the vehicle executes the command to apply high-voltage current, with the pre-charge resistor 37 acting as a current-limiting resistor to prevent the circuit from being subjected to a high current surge at the moment current is applied, which could cause damage to the electrical parts, wiring, and batteries in the circuit.

[0019] If the heating circuit is abnormally short-circuited, the fuse within the heating fuse 31 melts within a short time due to the accumulation of heat, thereby interrupting the heating circuit and protecting other electrical components, wires, and batteries in the circuit from damage. In a specific embodiment, if the current exceeds a certain value for a sufficiently long period, the device interrupts the circuit to which it is connected by switching on one or more specially designed fuses in proportion to this current. The details can be determined according to the general design requirements of the product, and the embodiment of the present application is not limited.

[0020] In this way, the area of ​​the printed circuit board 2 can be reduced based on the double-sided board layout, thereby saving the space occupied by the battery pack separator unit 10 inside the battery pack. Compared to the embodiment of a single-sided board layout of the electronic components with approximately the same electrical power configuration, the present solution can effectively reduce the size of the electrical compartment B and allocate a larger portion of the receiving space within the housing 20 to the side of the battery compartment A.

[0021] In a specific embodiment, the electrical compartment can have a projection area on the base plate 21 of the box body 20 of 5% to 20% of the area of ​​the base plate 21; for example, but not limited to, the projection area of ​​the electrical compartment B on the base plate 21 of the box body 20 is 6%, 12% or 18% of the area of ​​the base plate 21. This allows the volume of the battery pack to be increased accordingly and the overall energy density of the battery to be improved.

[0022] Furthermore, the electronic components can be flexibly arranged on the upper and lower surfaces of the printed circuit board. This reduces the mutual interference between the electronic components due to their own heat generation and facilitates heat dissipation. It also reduces electromagnetic interference between the electronic components to ensure the effective transmission of control signals.

[0023] To improve reliability, the electronic components on the top and bottom surfaces of printed circuit board 2 can be optimally configured. Optionally, the maximum height of each electronic component located on the bottom surface of printed circuit board 2 can be greater than the maximum height of each electronic component located on the top surface of printed circuit board 2. Here, "maximum height of each electronic component" refers to the height of the tallest electronic component among the many electronic components located on either the bottom or top surface of printed circuit board 2.

[0024] If large and heavy electronic components are arranged on the lower surface of printed circuit board 2 (PCB 2), the battery pack will experience combined vibration in the XYZ direction under operating conditions, with the Z direction being perpendicular to the base plate of the battery pack. In particular, when the entire battery pack vibrates in the Z direction, controlling the arrangement position of each electronic component within the BDU, placing tall components (large volume and weight) below the PCB, and lowering the overall center of gravity of the BDU can make it more stable. Furthermore, since small volume and weight electronic components are arranged on the upper surface of PCB 2, the possibility of crushing and damage to PCB 2 can be reduced.

[0025] If the maximum height of each electronic component located on the top surface of the printed circuit board (PCB) is less than or equal to the maximum height of each electronic component located on the bottom surface, PCB 2 can have a thickness of 0.5 mm to 2 mm. For example, the thickness of PCB 2 could be 0.6 mm, 1.2 mm, or 1.8 mm, without limitation. In this way, based on the load-bearing capacity of the substrate, the thickness of the board is reasonably controlled, the weight of the entire battery pack is reduced, the mass-energy density of the entire battery pack is improved to a certain extent, and the cost of the BDU PCB components themselves can be reduced.

[0026] In a specific embodiment, the ratio of the maximum height of each electronic element located on the upper surface of the printed circuit board 2 to the maximum height of each electronic element located on the lower surface of the printed circuit board 2 can be less than or equal to 1.27 and greater than or equal to 1. In this way, by reasonably controlling the height of the electronic element located on the upper surface of the printed circuit board 2, the center of gravity of the BDU is not placed too high, and the stability of the BDU housing is improved, thus avoiding the problem of fatigue failure of the solder joints at the connection points of the electronic elements under the vibration conditions of the entire battery pack.In particular, the connection between the high-voltage conductor series and the positive main relay and the negative main relay is generally screwed or welded, which, with repeated vibration of the entire battery pack, can lead to loosening of the screws, incorrect connection or fatigue failure and breakage of the weld, resulting in an increase in local resistance and a sudden increase in the amount of heat generated, and can even cause thermal runaway of the entire battery pack.

[0027] In the event that the maximum height of each electronic component located on the upper surface of printed circuit board 2 is greater than the maximum height of each electronic component located on the lower surface of printed circuit board 2, the thickness of printed circuit board 2 can be between 1 mm and 3 mm; for example, but not limited to, the thickness of printed circuit board 2 is 1.2 mm, 2 mm, or 2.8 mm. When the maximum height of the upper electronic component is greater than the maximum height of the lower electronic component, it is necessary, for reasons such as the external orientation of the BDU, to control the thickness of the printed circuit board within a suitable range to compensate for the decrease in stability due to the increased center of gravity and the structural damage to the printed circuit board of the BDU due to compression of the upper electronic component, thus further improving the stability and reliability of the BDU.

[0028] In other specific embodiments, at least a portion of the projection of each electronic element located on the lower plate face of the printed circuit board 2 coincides with the projection of each electronic element located on the upper plate face of the printed circuit board 2 in the plane in which the printed circuit board 2 is located. In this way, the upper and lower electronic elements are clamped to the upper and lower plate faces of the printed circuit board 2, and the upper and lower electronic elements jointly clamp the printed circuit board when the entire battery pack is vibrated in the Z-direction, which contributes to improving the overall rigidity of the printed circuit board 2 and reduces the risk of bending and breakage of the printed circuit board.

[0029] To improve the adaptability of the BDU, further optimizations can be made to the housing body 1, which forms the mounting base of the BDU. As described in the Fig. 2 and Fig. As shown in Figure 3, a clearance recess 13 can be provided on an outer surface of the housing body 1 to prevent interference with the reinforcement carrier 24 inside the electrical compartment, which runs perpendicular to the direction of extension of the circuit board 2, and to increase the overall structural strength of the electrical compartment. At least part of the structure of the reinforcement carrier 24 within the electrical compartment B can be installed in the clearance recess 13. In this way, the space available in the compartment can be adapted to improve the space utilization of the entire battery pack without increasing the installation space in the compartment.

[0030] The in Fig. The reinforcement beam 24 shown in Figure 2 is, by way of example, a beam structure. In a specific embodiment, the deflection recess 13 and the beam structure can be rigidly connected to each other, for example by adhesive bonding, an interference fit, or a concave-convex bond, to increase the stability of the BDU housing body 1. Under the vibration condition of the entire battery pack, the perforated reinforcement beam 24 is, on the one hand, equivalent to adding a support rod to the BDU housing body, thereby increasing the overall strength of the BDU, and on the other hand, it can also improve the strength of the electrical compartment through the strength of the BDU housing body, which works together to improve the electrical compartment as a whole, thus increasing the overall strength.Furthermore, the specific position and size of the escape recess 13 can be determined according to the general design requirements of the product, such as the arrangement of the electronic components on the circuit board in the housing body 1 and the specific shape of the reinforcement carriers in the electrical compartment. The embodiments of the present application do not limit this.

[0031] As in Fig. 6 and Fig. As shown in 7, Fig. 6 a schematic representation of the layout above the printed circuit board in an embodiment of the present invention, and Fig. Figure 7 is a schematic representation of the layout below the printed circuit board in an embodiment of the present invention;

[0032] In a specific embodiment, the escape recess 13 can be provided adaptably on the outer surface of the housing body 1. For example, in the area marked C in Fig. The position area shown in section 6 includes the escape recess 13 below the one shown in the diagram. Fig. 3 shown housing body 1 is provided, and in which the marking D in Fig. The position area shown in section 6 can be used to create the escape recess 13 above the area shown in the diagram. Fig. 3 shown housing body 1 provided.

[0033] In one specific embodiment, the projection of the escape recess 13 on the plane in which the printed circuit board 2 is located can be offset laterally from the electronic elements on the corresponding board surface in order to maximize space utilization in the vertical board surface direction and to efficiently control the space allocation of the battery pack separation unit. It is understood that the aforementioned corresponding position ranges in which the escape recesses can be located can be determined according to the design requirements of various products in order to obtain an outer contour of the housing body with good assembly adaptability, thereby achieving adaptation to a variety of electrical compartment structures. The embodiments of the present application do not limit this.

[0034] It should be noted that in practical application scenarios, the requirements for the strength of the entire battery pack are constantly increasing, and due to the complex and numerous high-voltage alignments in the electrical compartment, it is generally necessary to provide a beam structure in the electrical compartment to achieve improved structural strength. In the solution of the present application, the alternative recess 13 of this BDU housing body 1 provides a technical guarantee for fulfilling the alternative mounting requirement.

[0035] Optionally, the positive main relay 34 and the negative main relay 35 are located on the same side of the printed circuit board 2. This allows the connecting leads of the high and low voltage terminals of the positive main relay 34 and the negative main relay 35 to be arranged on the same side, which improves the overall layout and compactness. As shown in Fig. As shown in Figure 7, the positive main relay 34 and the negative main relay 35 are located at opposite ends of the lower plate surface of the circuit board 2. Due to the physical distance between the two and the physical barrier formed by the mounted beam structure, the electromagnetic interference between the two can be minimized.

[0036] In a specific embodiment, the main fuse 36 and the pre-charge resistor 37 can be provided between the positive main relay 34 and the negative main relay 35 in order to fully utilize the plate area of ​​the printed circuit board 2. Simultaneously, the copper array 5, which is connected to the positive main relay 34 and the negative main relay 35, is arranged on the same side of the printed circuit board 2 as these two relays, in order to further improve the utilization of the lower plate area of ​​the printed circuit board 2.

[0037] To make the internal structure layout more compact, the main board of the battery management system (BMS) of this battery pack separation unit 10 can optionally be stacked and fitted with the circuit board 2. As shown in Fig. As shown in 8, Fig. 8 a schematic representation of the assembly relationship between the printed circuit board and the BMS main board in an embodiment of the present invention.

[0038] The BMS main board is located on the circuit board and is situated on the side of the circuit board opposite the positive main relay and the negative main relay, thus preventing the BMS main board 4 from interfering with the copper row 5. In combination with the Fig. 4, Fig. 6 and Fig.8. The electronic components, such as the heating fuse 31, the heating relay 32, and the pre-charging relay 33, can be arranged centrally in a side area of ​​the upper surface of the circuit board 2, and the BMS main board 4 can be arranged on the circuit board 2 next to the heating fuse 31, the heating relay 32, and the pre-charging relay 33. In this way, the overall structure becomes more compact and efficient, and the space required for the battery pack separation unit 10 in the battery compartment is reduced.

[0039] In one specific embodiment, at least part of the projection of the BMS mainboard 4 onto the plane in which the circuit board 2 is located can coincide with the circuit board 2. Of course, the projection of the BMS mainboard 4 onto the plane in which the circuit board 2 is located can also coincide entirely with the circuit board 2.

[0040] Accordingly, a high-voltage sensing connector 6 can be provided on the upper surface of the printed circuit board 2 and a low-voltage communication connector 7 on the lower surface of the printed circuit board 2, and corresponding electrical connections with the BMS main board 4 can each be realized by either of them.

[0041] In other possible embodiments, other functional components may be provided on the upper and lower plate surfaces of the circuit board 2, which will not be repeated here.

[0042] It should be noted that other functions of the battery pack and the battery pack separation unit 10, which are described in the exemplary embodiments of the present application, do not constitute core aspects of the invention of the present application and can be implemented by a person skilled in the art on the basis of the prior art and are not repeated here.

[0043] The foregoing is only a preferred embodiment of the present invention, and it should be noted that for a person of ordinary knowledge in the field, a number of improvements and embodiments can be made without derogation from the principles of the present invention, and these improvements and embodiments should also be considered as being within the scope of protection of the present invention.

Claims

[1] Battery pack, characterized by that it comprises a box body, a battery group and a battery pack separation unit, wherein the box body comprises a base plate and a box frame, the box frame being attached to the base plate and enclosing a receiving space of the box body; wherein a partition support is provided inside the box body, the partition support dividing the receiving space into a battery compartment and an electrical compartment; wherein the battery group is provided within the battery compartment, wherein the battery pack separation unit is provided within the electrical compartment; wherein the battery pack separation unit comprises a housing body, a printed circuit board and an electronic element connected to the printed circuit board, wherein the printed circuit board is provided inside the housing body, and wherein the electronic element is arranged on plate surfaces on both sides of the printed circuit board; wherein the electronic element comprises a positive main relay and a negative main relay, wherein the battery pack further comprises a copper row, wherein the copper row is connected to the positive main relay and the negative main relay and is arranged on the same side of the circuit board as the positive main relay and the negative main relay. [2] Battery pack according to claim 1, characterized by , that the maximum height of each electronic element located on a lower plate surface of the printed circuit board is greater than the maximum height of each electronic element located on an upper plate surface of the printed circuit board. [3] Battery pack according to claim 1, characterized by, that the ratio of the maximum height of each electronic element located on the upper plate surface of the printed circuit board to the maximum height of each electronic element located on the lower plate surface of the printed circuit board is less than or equal to 1.

27. [4] Battery pack according to claim 1, characterized by , that at least part of the projection of each electronic element located on the lower plate surface of the printed circuit board coincides with the projection of each electronic element located on the upper plate surface of the printed circuit board onto a plane in which the printed circuit board is located. [5] Battery pack according to claim 1, characterized by, that the maximum height of each electronic element located on the top surface of the printed circuit board is greater than the maximum height of each electronic element located on the bottom surface of the printed circuit board, the printed circuit board having a thickness of 1 mm to 3 mm. [6] Battery pack according to claim 1, characterized by , that the maximum height of each electronic element located on the top surface of the printed circuit board is less than or equal to the maximum height of each electronic element located on the bottom surface of the printed circuit board, the printed circuit board having a thickness of 0.5 to 2 mm. [7] Battery pack according to any one of claims 1 to 6, characterized by that an escape recess is provided on an outer surface of the housing body. [8] Battery pack according to claim 7, characterized by, that the projection of the escape recess on the plane on which the circuit board is located is offset from the electronic element on the board surface on the corresponding side of the circuit board. [9] Battery pack according to any one of claims 1 to 6, characterized by , that the positive main relay and the negative main relay are located on the lower surface of the circuit board. [10] Battery pack according to claim 9, characterized by that the positive main relay and the negative main relay are located at opposite ends of the lower plate surface of the circuit board. [11] Battery pack according to claim 9, characterized by , that the electronic element further comprises a heating relay and a pre-charging relay, wherein the heating relay and the pre-charging relay are arranged on the upper surface of the printed circuit board. [12] Battery pack according to claim 9, characterized by, that the battery pack separation unit further comprises a BMS main board, wherein the BMS main board is arranged on the printed circuit board and is located on a side of the printed circuit board opposite the positive main relay and the negative main relay. [13] Battery pack according to claim 7, characterized by that the electrical compartment has a projection area on the base plate of 5% to 20% of the area of ​​the base plate, wherein a reinforcement carrier is provided inside the electrical compartment, wherein the reinforcement carrier extends in a direction perpendicular to the extension direction of the circuit board, and wherein at least a part of the reinforcement carrier is installed in the escape recess. [14] Battery pack according to claim 13, characterized by , that the battery pack separation unit is firmly connected to the reinforcement carrier through the escape recess. [15] Battery pack according to claim 1, characterized by, that a BMS mainboard is stacked with the circuit board. [16] Battery pack according to claim 15, characterized by , that at least part of the projection of the BMS mainboard on the plane in which the circuit board is located coincides with the circuit board. [17] Battery pack according to claim 15, characterized by that the printed circuit board is provided with a high-voltage scanning connector on the upper surface of the board and with a low-voltage communication connector on the lower surface of the board, wherein the printed circuit board is electrically connected to the BMS main board via the high-voltage scanning connector and the low-voltage communication connector.

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