Battery monitoring device
The battery monitoring device addresses size and accuracy issues by employing a recessed wiring board design and connector placement, resulting in a compact, cost-effective solution with enhanced voltage monitoring and extended vehicle range.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- DENSO CORP
- Filing Date
- 2022-10-11
- Publication Date
- 2026-05-19
AI Technical Summary
Existing battery monitoring devices face challenges with increased physical size due to the use of through-type terminals, which protrude in the thickness direction of the circuit board, necessitating further improvements.
A battery monitoring device design featuring a wiring board with recesses on its sides to accommodate connectors and circuit components, including a battery monitoring IC, positioned to reduce thickness and warping, and connectors fixed without protruding beyond the board surface, thereby minimizing overall size and maintaining accurate voltage monitoring.
The design achieves a reduced physical size without the need for reinforcing members, ensuring accurate voltage monitoring and extending the vehicle's driving range while adhering to collision protection requirements and reducing costs.
Smart Images
Figure 0007861600000001 
Figure 0007861600000002 
Figure 0007861600000003
Abstract
Description
Technical Field
[0001] The present disclosure relates to a battery monitoring device.
Background Art
[0002] As an example of a battery monitoring device, there is a technique disclosed in Patent Document 1. The battery monitoring device includes a battery information input terminal electrically connected to a battery state detection member, a battery state monitoring unit to which a battery state detection signal is input via the battery information input terminal, an output terminal that outputs monitoring information on the battery state corresponding to the battery state detection signal to an external arithmetic processing device, and a circuit board on which these are mounted. Further, the battery monitoring device uses a through-type terminal that penetrates the circuit board as the battery information input terminal.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] Since the above battery monitoring device uses a through-type terminal, the terminal protrudes in the thickness direction of the circuit board. Therefore, the battery monitoring device has a problem that its physical size in the thickness direction becomes large. Further, from the above viewpoints or other viewpoints not mentioned, further improvement of the battery monitoring device is required.
[0005] One object of the disclosure is to provide a battery monitoring device with a reduced physical size.
Means for Solving the Problems
[0006] The battery monitoring device disclosed herein is a battery monitoring device that monitors the state of a battery mounted on a vehicle, A wiring board (10) on which a portion of the wiring (12) is provided on one side (S1), Circuit components (21, 22) are surface-mounted on one side and connected to wiring, A connector member (30) that electrically connects a wiring board and at least a battery, and has a terminal (31) connected to a land (13a) which is part of the wiring provided on one surface, and a housing (33) on which the terminal is provided, The wiring board has a recess (14) on a part of its side that is lower than the surrounding area, and at least a part of the housing is positioned in the recess. Occasionally, The circuit components include other circuit elements and a battery monitoring IC which is larger than the other circuit elements. The wiring board has short side surfaces (S4, S6) that run along the shorter direction of one surface, and long side surfaces (S3, S5) that run along the longer direction of one surface and have recesses provided therein. The battery monitoring IC is located in a narrow region (OA) adjacent to the recess on one surface in the short-side direction. .
[0007] Thus, the battery monitoring device has terminals connected to lands provided on one side of the wiring board. Furthermore, at least a portion of the housing of the battery monitoring device is positioned in a recess provided on the side of the wiring board. Therefore, the battery monitoring device can be made smaller in size in the thickness direction of the wiring board.
[0008] The various embodiments disclosed in this specification employ different technical means to achieve their respective objectives. The claims and the reference numerals in parentheses in this section are illustrative in their correspondence with the embodiments described later and are not intended to limit the technical scope. The objectives, features, and effects disclosed in this specification will become clearer by referring to the subsequent detailed description and the accompanying drawings. [Brief explanation of the drawing]
[0009] [Figure 1] This is an illustrative diagram showing an example of a battery monitoring device being installed. [Figure 2] This is a perspective view showing the schematic configuration of the battery monitoring device. [Figure 3] This is a plan view showing the schematic configuration of a wiring board. [Figure 4]This is a cross-sectional view along the line IV-IV in Figure 3. [Figure 5] This is a cross-sectional view along the line V-V in Figure 3. [Figure 6] This is a plan view showing the schematic configuration of a wiring board before connector components are attached. [Figure 7] This is a plan view showing the schematic configuration of the wiring board in modified example 1. [Modes for carrying out the invention]
[0010] In the following, several embodiments for implementing this disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to matters described in a prior embodiment may be denoted by the same reference numerals, and redundant descriptions may be omitted. If only a part of the configuration is described in each embodiment, other parts of the configuration can be referred to and applied to other embodiments described in advance.
[0011] In the following, the three mutually orthogonal directions will be referred to as the X, Y, and Z directions. The plane defined by the X and Y directions will be referred to as the XY plane. Unless otherwise specified, a plan view refers to a drawing viewed from the Z direction.
[0012] <Battery Pack> First, let's describe the battery pack 300 on which the battery monitoring device 100 is mounted. The battery pack 300 is located under the vehicle's seat. Alternatively, the battery pack 300 may be located in other places, such as the vehicle's engine compartment, trunk, or under the floor. The vehicle is an electric vehicle or hybrid vehicle that runs using the electricity stored in the battery pack 300. In other words, the battery pack 300 is mounted in the vehicle as the vehicle's power source.
[0013] The battery pack 300 includes a plurality of battery modules 200 each containing a plurality of battery cells. Each battery cell is composed of a lithium-ion secondary battery, a nickel-metal hydride secondary battery, or the like. Note that a lithium-ion secondary battery is a secondary battery that uses lithium as a charge carrier, and may include not only a general lithium-ion secondary battery with a liquid electrolyte but also a so-called all-solid-state battery that uses a solid electrolyte. The battery module 200 corresponds to a battery.
[0014] The battery pack 300 (battery module 200) stores electric power in the battery cells for driving the vehicle's driving motor and is configured to supply electric power to the driving motor. The battery pack 300 is charged by receiving the generated electric power of the driving motor during regenerative power generation of the driving motor, such as during vehicle braking. The driving motor corresponds to an electric motor for driving the vehicle.
[0015] As shown in FIG. 1, the battery pack 300 includes a plurality of battery modules 200, a plurality of battery monitoring devices 100, and a battery housing that houses them. In the battery pack 300, two battery modules 200 are arranged along the left-right direction LD of the vehicle. However, in the battery pack 300, a plurality of battery modules 200 may be arranged along the frontward direction FD of the vehicle. Also, in the battery pack 300, three or more battery modules 200 may be arranged along the left-right direction LD of the vehicle. Thus, in the battery pack 300, a plurality of battery modules 200 may be arranged in two or more rows and two or more columns. The plurality of battery modules 200 may be arranged in a state rotated 90° from the state shown in FIG. 1. That is, in the battery pack 300, a plurality of battery modules 200 and battery monitoring devices 100 may be arranged side by side along the frontward direction FD. One battery monitoring device 100 may be provided for a plurality of battery modules 200, or one battery monitoring device 100 may be provided for one battery module 200. The size of the battery pack 300 in the left-right direction LD is restricted due to side impact protection requirements. Note that the frontward direction FD is parallel to the front-rear direction of the vehicle.
[0016] The battery pack 300 is connected to a vehicle control device, a power control unit, and the like. The power control unit performs bidirectional power conversion between the battery pack 300 and the drive motor according to a control signal from the vehicle control device. The power control unit includes, for example, an inverter that drives the drive motor and a converter that boosts the DC voltage supplied to the inverter to be higher than the output voltage of the battery pack 300.
[0017] The vehicle control device includes a CPU, a ROM, a RAM, input / output ports for inputting / outputting various signals, and the like. The CPU develops and executes the program stored in the ROM in the RAM. The program stored in the ROM describes the processing of the vehicle control device. The vehicle control device acquires battery information, which will be described later from the battery monitoring device 100, and controls the power control unit. Thereby, the driving of the drive motor and the charging / discharging of the battery pack 300 are controlled.
[0018] <Battery Monitoring Device> The battery monitoring device 100 includes a wiring board 10, circuit components 21, 22, a connector 30, a base 41, a cover 42, and the like. The battery monitoring device 100 is a device that monitors the state of a battery module 200 (battery cell) mounted on a vehicle. The battery monitoring device 100 is provided in the battery pack 300.
[0019] <Wiring Board and Circuit Components> As shown in FIGS. 3 and 4, the wiring board 10 has an insulating substrate 11 mainly composed of resin or the like and a conductive wiring 12 mainly composed of metal such as copper. In the present embodiment, as an example of the wiring board 10, a multilayer substrate in which the wiring 12 is laminated via the insulating substrate 11 is adopted. That is, in the wiring board 10, the wiring 12 is formed in a plurality of insulating layers constituting the insulating substrate 11. And the wiring board 10 is configured by laminating the plurality of insulating layers. The wiring board 10 can adopt, for example, one in which about several insulating layers are laminated. However, the wiring board 10 is not limited to a multilayer substrate.
[0020] The wiring board 10 has a roughly rectangular shape in plan view. The longitudinal direction of the wiring board 10 coincides with the X direction, and the short direction coincides with the Y direction. The wiring board 10 has a substrate surface S1 and a substrate back surface S2 which is the opposite surface of the substrate surface S1. The substrate surface S1 and the substrate back surface S2 are surfaces that are roughly parallel to the XY plane. The substrate surface S1 and the substrate back surface S2 are roughly rectangular in shape. Hereinafter, the longitudinal direction of the wiring board 10 will be simply referred to as the longitudinal direction, and the short direction of the wiring board 10 will be simply referred to as the short direction. The substrate surface S1 corresponds to one surface, and the substrate back surface S2 corresponds to the opposite surface.
[0021] The wiring board 10 has sides S3 to S6 that are connected to the substrate surface S1 and the substrate back surface S2. The wiring board has short sides S4 and S6 that run along the short direction and long sides S3 and S5 that run along the long direction. Sides S3 to S6 are planes that are approximately perpendicular to the XY plane. In Figure 3, CL is a center line that passes through the center in the long direction and runs along the short direction. The center line CL is a hypothetical line shown.
[0022] The wiring board 10 has a portion of the wiring 12 provided on the substrate surface S1. In this embodiment, an example is adopted in which the wiring 12 is provided not only on the substrate surface S1 but also inside the insulating substrate 11. The wiring 12 includes mounting lands 13a as a portion provided on the substrate surface S1 of the wiring board 10. The mounting lands 13a are the portion of the wiring 12 that is exposed on the substrate surface S1 side. The mounting lands 13a correspond to lands. In Figure 4, the portion of the wiring 12 to which the element terminal 21a is connected is the portion of the wiring 12 that is exposed on the substrate surface S1 side and can also be called a circuit mounting land.
[0023] As shown in Figure 3, the wiring board 10 has fixing lands 13b for fixing the connector 30 (fixing member 32), which will be explained later. The fixing lands 13b are provided on the substrate surface S1. The fixing lands 13b are made of the same material as the wiring 12. However, the fixing lands 13b are electrically isolated from the wiring 12. The fixing member 32 is fixed to the fixing lands 13b by solder.
[0024] Furthermore, the fixing lands 13b are provided around the notch 14 where the connector case 33, which will be described later, is positioned. Here, as an example, fixing lands 13b provided on both sides of the notch 14 in the longitudinal direction are used. The fixing lands 13b have a rectangular shape in which, for example, the length in the longitudinal direction is shorter than the length in the short direction when viewed from above.
[0025] However, the fixing land 13b may have a longer longitudinal length than described above in a plan view. By increasing the longitudinal length of the fixing land 13b, the fixing strength with the fixing member 32 can be improved. This improves the durability of the fixing land 13b against the stress applied when the mating connector is inserted into and removed from the connector 30. Hereinafter, this stress will also be referred to as the insertion / removal stress.
[0026] As shown in Figures 3, 4, and 6, the wiring board 10 has a notch 14 on a part of its side surface S3 to S6 that is recessed compared to the surrounding area. The notch 14 is the area where the connector 30 is placed. More specifically, the notch 14 is the area where the connector case 33, which is part of the connector 30, is placed. The notch 14 can also be said to be the area where the connector case 33 is attached. It can also be said that the connector case 33 is placed in the space defined by the notch 14.
[0027] Therefore, the notch 14 can also be described as a connector placement area or placement recess. Furthermore, the notch 14 can be said to form a through hole that extends from the substrate surface S1 to the substrate back surface S2 on the longitudinal side surface S3. Moreover, the notch 14 can be said to be composed of three consecutive surfaces of the wiring board 10. These three surfaces are two opposing surfaces along the Y direction and a connecting surface that connects the two opposing surfaces along the X direction. The notch 14 corresponds to a recess.
[0028] In this embodiment, as an example, a wiring board 10 is used in which a notch 14 is provided on the longitudinal side surface S3. That is, the notch 14 is a recessed portion on the longitudinal side surface S3 compared to the area around the notch 14. Furthermore, in this embodiment, as an example, a wiring board 10 is used in which notches 14 are provided in four places on the longitudinal side surface S3. Therefore, when the longitudinal side surface S3 of the wiring board 10 is viewed from the Y direction, there are four recesses, which are the notches 14, provided at intervals from each other.
[0029] The notch 14, in plan view, has a shape that corresponds to the outer shape of the connector case 33. In other words, the shape of the notch 14 in the XY plane is the same as the shape of the connector case 33 in the XY plane. Also, the area of the notch 14 in the XY plane is approximately the same as the area of the connector case 33 in the XY plane. That is, the notch 14 only needs to be large enough to accommodate the connector case 33.
[0030] However, the notch 14 is not limited to the above, and the notch 14 may be provided on sides S4 to S6 other than the longitudinal side S3. Furthermore, the present disclosure may provide only one, two, three, five or more notches 14. Moreover, the length of the notch 14 in the short direction may be shorter than the length of the connector case 33 in the short direction. In this case, the connector case 33 will protrude from the longitudinal side S3 when positioned in the notch 14.
[0031] As shown in Figure 3, the wiring board 10 is provided with fixing holes 15. The fixing holes 15 are through holes for screwing the wiring board 10 to the base 41, which will be explained later. In other words, the wiring board 10 is fixed to the base 41 by screws. The fixing holes 15 are provided in positions that sandwich at least the notch 14. In other words, it can be said that the wiring board 10 has fixing holes 15 on both sides of the notch 14 in the longitudinal direction. This suppresses the transmission of insertion and removal stress to the wiring board 10. Therefore, the wiring board 10 can reduce the stress on the battery monitoring IC 21, which will be explained later. The fixing holes 15 correspond to the fixing parts.
[0032] In this embodiment, an example is adopted in which the notches 14 are provided in positions other than those where they are sandwiched. Also, the wiring board 10 may be fixed to the base 41 by a method other than screw fastening. Other methods include adhesive fastening, fitting fastening, heat crimping, and even a method of fixing by pressing the base 41 and cover 42 together.
[0033] Incidentally, as shown in Figure 5, in this embodiment, a wiring board 10 is used that is curved such that the substrate surface S1 side has a convex shape due to the difference in the coefficient of linear expansion between the insulating substrate 11 and the wiring 12. Furthermore, the wiring board 10 is prone to warping because it has a notch 14 as described above. In other words, the wiring board 10 has partially different lengths in the short side due to the notch 14. Therefore, the wiring board 10 is prone to warping in the parts where the length in the short side is short. However, this disclosure is not limited to this, and a wiring board 10 that is curved such that the substrate surface S1 side has a concave shape can also be used.
[0034] Areas with a short length in the shorter direction are referred to as opposing regions OA. Opposing regions OA are areas on the substrate surface S1 adjacent to the notch 14 in the shorter direction. Opposing regions OA can also be described as areas facing the notch 14 in the shorter direction in a plan view. Opposing regions OA can also be described as areas on the substrate surface S1 aligned with the notch 14. Opposing regions OA can also be described as a part of the substrate surface S1 in the area facing the notch 14 in the shorter direction. The length of opposing regions OA in the longer direction matches the length of the notch 14 in the longer direction. Opposing regions OA correspond to narrow regions.
[0035] As shown in Figures 3 and 4, the wiring board 10 has multiple circuit components 21 and 22 surface-mounted on the board surface S1. In other words, the circuit components 21 and 22 are surface-mount type chips such as BGA and QFP. BGA is an abbreviation for Ball Grid Array. QFP is an abbreviation for Quad Flat Package.
[0036] The battery monitoring device 100 has a battery monitoring IC 21 and circuit elements 22 that are different from the battery monitoring IC 21 mounted as circuit components. The circuit elements 22 are, for example, circuit components that make up a communication circuit or circuit components that provide other functions.
[0037] The battery monitoring IC 21 is an IC chip that has the function of monitoring the voltage of the battery module 200. More specifically, the battery monitoring IC 21 acquires battery information from each battery cell that makes up the battery module 200. This battery information includes at least the voltage information of each battery cell. The battery information may also include temperature information, current information, self-diagnosis information, etc., for each battery cell. Self-diagnosis information refers to, for example, information related to the operation confirmation of the battery monitoring device 100, that is, information related to abnormalities or failures of the battery monitoring device 100. The battery monitoring IC 21 can also be called a cell supervising circuit (CSC).
[0038] As shown in Figure 4, the battery monitoring IC 21 is equipped with element terminals 21a. Element terminals 21a are connected to wiring 12 by solder 16. Similarly, circuit element 22 is also connected to wiring 12. In other words, each circuit component 21 and 22 is connected to a part of wiring 12 via solder 16. Thus, circuit components 21 and 22 together with wiring 12 constitute a circuit.
[0039] In this embodiment, circuit components 21 and 22 connected to the wiring 12 by reflow soldering are used. The connector 30, which will be described later, is also connected to the wiring 12 by reflow soldering. The connector 30 has terminals 31 and mounting land 13a, and fixing member 32 and fixing land 13b, all connected by reflow soldering. The circuit components 21 and 22 and the connector 30 are connected to the wiring 12 and the like in the same reflow soldering process.
[0040] As shown in Figure 3, the battery monitoring IC 21 is mounted so that at least a portion of it is located in the opposing region OA. The opposing region OA is the area where the wiring board 10 is prone to warping, as described above. Furthermore, the battery monitoring IC 21 is a larger chip than the other circuit elements 22. In addition, the battery monitoring IC 21 is also a heavier chip than the other circuit elements 22.
[0041] Therefore, the battery monitoring device 100 suppresses (reduces) the warping of the wiring board 10 by placing a part of the battery monitoring IC 21 in the opposing region OA, thereby utilizing the weight of the battery monitoring IC 21. It can also be said that the battery monitoring device 100 can suppress the warping of the wiring board 10 in the area where the battery monitoring IC 21 is mounted. Preferably, in a plan view, the entire battery monitoring IC 21 is placed in the opposing region OA. This further reduces the warping of the wiring board 10. As an example, the battery monitoring device 100 employs a wiring board 10 that is warped such that the substrate surface S1 side becomes convex while the warping is suppressed by the weight of the battery monitoring IC 21. However, this disclosure is not limited to this. The battery monitoring device 100 may also include a wiring board 10 that is warped such that the substrate surface S1 side becomes concave while the warping is suppressed by the weight of the battery monitoring IC 21. Furthermore, the battery monitoring device 100 may include a wiring board 10 in which the substrate surface S1 is flat while warping is suppressed by the weight of the battery monitoring IC 21.
[0042] The battery monitoring device 100 can reduce the stress applied to the battery monitoring IC 21 by reducing the warping of the wiring board 10. Similarly, the battery monitoring device 100 can reduce the stress applied to the connection points between the battery monitoring IC 21 and the wiring board 10. Furthermore, the battery monitoring device 100 can reduce mounting defects of the battery monitoring IC 21 caused by the warping of the wiring board 10. The stress referred to here is the stress associated with the warping of the wiring board 10, and is also called warping stress. The connection points are the element terminals 21a, solder 16, and wiring 12.
[0043] Incidentally, the battery monitoring IC21 may experience distortion when warping stress is applied to the wiring board 10. As a result, the battery monitoring IC21 has the problem of reduced voltage monitoring accuracy. In other words, the battery monitoring IC21's monitoring accuracy is greatly affected by the warping stress of the wiring board 10. On the other hand, the requirements for voltage monitoring accuracy are extremely high in order to ensure safety and extend the driving range. For this reason, it is conceivable to provide reinforcing members to suppress warping of the wiring board 10. However, the battery monitoring device 100 has the problem of increased cost due to the addition of reinforcing members.
[0044] To address these issues, this disclosure places a portion of the battery monitoring IC 21 in the opposing region OA. This allows the battery monitoring device 100 to suppress warping of the wiring board 10 as described above, and reduce the warping stress applied to the battery monitoring IC 21. As a result, the battery monitoring device 100 can suppress a decrease in the accuracy of voltage monitoring by the battery monitoring IC 21. In other words, the battery monitoring device 100 can accurately monitor voltage information, which is one of the battery information transmitted to the vehicle control device.
[0045] The vehicle control unit then controls the operation of the drive motor and the charging and discharging of the battery pack 300 via the power control unit based on battery information. Therefore, the vehicle control unit can perform control based on accurate voltage information. Thus, the battery monitoring device 100 can extend the vehicle's driving range while ensuring safety. Furthermore, since the battery monitoring device 100 does not require reinforcing members, it can suppress high costs.
[0046] In this embodiment, as an example, a wiring board 10 is used in which more circuit components 21 and 22 are mounted on the surface S1 of the substrate than on the back surface S2 of the substrate. This allows the insulating distance (space) between each circuit component 21 and 22 and the base 41 and cover 42 to be secured only on the surface S1 side of the substrate. Therefore, the battery monitoring device 100 can be made thinner in the Z direction.
[0047] Furthermore, the wiring board 10 has a convex shape on the board surface S1 side, and it may warp so that the apex of the convex shape aligns with the center line CL. In particular, wiring boards 10 with multiple notches 14 formed in the longitudinal direction are prone to this warping. Therefore, the battery monitoring device 100 may place the battery monitoring IC 21 on the center line CL. This can also suppress the warping of the wiring board 10.
[0048] <Connector> The connector 30 is an external connection component for connecting the wiring board 10 to an external device provided outside the wiring board 10. The connector 30 electrically connects the wiring board 10 to at least the battery module 200. In other words, the battery monitoring device 100 includes at least one connector 30 that electrically connects the wiring board 10 to the battery module 200. Therefore, the battery monitoring device 100 may also include a connector 30 that electrically connects the wiring board 10 to an external device other than the battery module 200. The battery module 200 is an example of an external device. External devices may include a vehicle control device or a power control unit.
[0049] As shown in Figure 4 and other figures, the connector 30 has a terminal 31 connected to a mounting land 13a, which is part of the wiring 12 provided on the substrate surface S1, and a connector case 33 on which the terminal 31 is provided. Furthermore, the connector 30 has a fixing member 32. Note that the connector 30 corresponds to a connector component. The fixing member 32 corresponds to a fixing terminal. The connector case 33 corresponds to a housing.
[0050] The terminal 31 is a conductive material mainly composed of metal. The connector case 33 is an insulating material mainly composed of resin. The fixing member 32 is made of the same material as the terminal 31. The terminal 31 and the fixing member 32 are provided in the connector case 33, for example, by insert molding.
[0051] The connector 30 has a portion of its terminals 31 connected to the mounting pad 13a by solder 16. The mounting pad 13a is provided on the substrate surface S1 as described above. In other words, the connector 30 is connected to a portion of the wiring 12 on the surface of the wiring board 10 without the terminals 31 being inserted into the wiring board 10. Therefore, the connector 30 can be described as a surface-mount type connector. However, the connector 30 is fixed to the wiring board 10 without the connector case 33 being placed on the substrate surface S1. This point will be explained later.
[0052] The connector case 33 has a box shape, for example, with an opening in one direction. In other words, the connector case 33 has a configuration with five walls. The connector case 33 has a connector surface S11 and a connector back surface S12 as the surfaces of two opposing walls. The connector back surface S12 is the surface opposite to the connector surface S11. The connector back surface S12 corresponds to the bottom surface of the housing.
[0053] The connector case 33 has an insertion opening 34 enclosed by its walls. The insertion opening 34 is the part into which the mating connector is inserted. The connector case 33 is also configured to allow the mating connector inserted into the insertion opening 34 to be removed. The direction of insertion and removal of the mating connector from the connector 30 is along the Y direction.
[0054] The terminal 31 is provided on the connector case 33 so as to protrude from both sides of one wall section. A portion of the terminal 31 is positioned in the insertion opening 34. The wall section on which the terminal 31 is provided is the part that faces the connection surface when the connector case 33 is positioned in the notch 14.
[0055] The connector 30 is mounted with at least a portion of the connector case 33 positioned in the notch 14. In other words, a portion of the connector 30 between the connector surface S11 and the connector back surface S12 of the connector case 33 is positioned in the notch 14. Therefore, it can be said that the connector case 33 is not positioned on the substrate surface S1.
[0056] In this embodiment, as an example, a connector 30 is used in which the back surface S12 of the connector is positioned at the same location as the back surface S2 of the circuit board 10 in the thickness direction of the circuit board 10. In other words, the connector case 33 does not protrude beyond the back surface S2 of the circuit board in the Z direction, but rather protrudes toward the surface S1 of the circuit board. As a result, the battery monitoring device 100 can be made smaller in the thickness direction than a configuration in which the connector case 33 is mounted on the surface S1 or back surface S2 of the circuit board 10. Note that the thickness direction coincides with the Z direction.
[0057] As described above, the wiring board 10 needs to maintain an insulating distance from the cover 42 on the board surface S1 side. In other words, the battery monitoring device 100 has a wider gap between the board surface S1 and the cover 42 than between the back surface S2 and the base. Therefore, when the battery monitoring device 100 is equipped with a base 41 and a cover 42, even if the connector case 33 protrudes toward the board surface S1 side, the overall size in the thickness direction of the board does not increase significantly. Thus, the battery monitoring device 100 can be made smaller in the thickness direction than a configuration in which the connector case 33 protrudes toward both the board surface S1 and the back surface S2 of the board.
[0058] However, the positional relationship between the connector 30 and the wiring board 10 is not limited to the above. This disclosure can also be adopted, for example, in a configuration in which the connector case 33 protrudes from both the surface S1 and the back surface S2 of the substrate.
[0059] As shown in Figure 3, the connector 30 has a fixing member 32 provided on the side wall of the connector case 33. The fixing member 32 is connected to the fixing land 13b as described above. The connector 30 is fixed to the wiring board 10 by the fixing member 32 being connected to the fixing land 13b when it is positioned in the notch 14. In other words, the connector 30 is not fixed to the wiring board 10 by the connector case 33 being deformed at least partially by mating or the like, but rather is fixed to the wiring board 10 by solder.
[0060] This allows the battery monitoring device 100 to firmly fix the connector 30 to the wiring board 10. The battery monitoring device 100 can suppress the application of insertion / extraction stress to the terminals 31 and the connection points between the terminals 31 and the mounting lands 13a. Furthermore, the battery monitoring device 100 can suppress the displacement (deformation) of the wiring board 10 due to the insertion / extraction stress, thereby suppressing a decrease in the voltage monitoring accuracy of the battery monitoring IC 21.
[0061] Furthermore, it can be said that the connector case 33 is positioned only in the notch 14 when viewed from above. In other words, the connector case 33 is not positioned in any area where the notch 14 is not formed when viewed from above.
[0062] <Enclosure> As shown in Figure 2, the battery monitoring device 100 comprises a base 41 and a cover 42 as its housing. The base 41 and cover 42 are mainly composed of a metal such as aluminum. The wiring board 10 is fixed to the base 41 as described above. The cover 42 is attached to the base 41, and together with the base 41, forms a space for housing the wiring board 10. The manner in which the base 41 and the cover 42 are fixed is not particularly limited. The base 41 and the cover 42 may be mainly composed of resin. Furthermore, one of the base 41 and the cover 42 may be mainly composed of resin, and the other may be mainly composed of metal.
[0063] The housing space accommodates not only the wiring board 10, but also the circuit components 21 and part of the connector 30. The connector 30 is housed so that its insertion opening 34 is exposed to the outside of the housing space. This allows the battery monitoring device 100 to make an electrical connection with an external device via the connector 30. In this way, the battery monitoring device 100 has the wiring board 10 and other components covered by the base 41 and cover 42. Therefore, the battery monitoring device 100 can suppress the adhesion and collision of foreign matter to the wiring board 10 and other components. In addition, the battery monitoring device 100 can suppress adverse electrical influences transmitted to the wiring board 10 from outside the housing space. In other words, the battery monitoring device 100 can ensure the insulation of the wiring board 10 on which the circuit components 21 and 22 are mounted.
[0064] <Example of battery monitoring device placement> As shown in Figure 1, the battery monitoring device 100 is positioned between the battery modules 200 in the left-right direction LD. In this embodiment, the forward direction FD coincides with the X direction, and the left-right direction LD coincides with the Z direction. Therefore, the wiring board 10 is positioned with its short side aligned with the left-right direction LD and its long side aligned with the forward direction FD, and is positioned between the multiple battery modules 200 positioned in the left-right direction LD.
[0065] The battery monitoring device 100 may be positioned between the battery modules 200 in the forward direction FD. Alternatively, the battery monitoring device 100 may be positioned between the battery modules 200 and the vehicle seats.
[0066] <Effects> As described above, the battery monitoring device 100 has terminals 31 connected to mounting lands 13a provided on the substrate surface S1 of the wiring board 10. Furthermore, at least a portion of the connector case 33 of the battery monitoring device 100 is positioned in a notch 14 provided on the longitudinal side surface S3 of the wiring board 10. As a result, the battery monitoring device 100 can be made smaller in the thickness direction of the wiring board 10. In other words, the battery monitoring device 100 can be made lower in the thickness direction of the wiring board 10.
[0067] Furthermore, the battery monitoring device 100 achieves both a low profile and suppression of a decrease in voltage monitoring accuracy due to warping of the wiring board 10 by arranging at least a portion of the battery monitoring IC 21 in the opposing region OA. The battery monitoring device 100 also achieves both a low profile and suppression of a decrease in voltage monitoring accuracy due to displacement of the wiring board 10 by connecting the fixing member 32 to the fixing land 13b.
[0068] Incidentally, the size of the lateral LD of the battery pack 300 is limited by the side impact protection requirements. However, as described above, the battery monitoring device 100 can be made lower in the thickness direction of the wiring board 10. Furthermore, the thickness direction of the wiring board 10 of the battery monitoring device 100 coincides with the lateral LD. Therefore, the battery monitoring device 100 can suppress a reduction in the number of battery modules 200 mounted in the lateral LD. In other words, the battery monitoring device 100 can secure the number of battery modules 200 mounted while satisfying the collision protection requirements. In addition, because the battery monitoring device 100 is positioned between the battery modules 200 in the lateral LD, it can suppress a reduction in the passenger space of the vehicle.
[0069] Furthermore, as described above, the battery monitoring device 100 can be made lower in the thickness direction of the wiring board 10. Therefore, when the battery monitoring device 100 is configured to be placed between the battery modules 200 in the longitudinal direction of the vehicle, it can suppress a reduction in the number of battery modules 200 installed in the longitudinal direction of the vehicle. Also, when the battery monitoring device 100 is configured to be placed between the battery modules 200 and the vehicle seats, it can suppress a reduction in the passenger space of the vehicle.
[0070] Furthermore, the battery monitoring device 100 does not require reinforcing members to suppress warping of the wiring board 10. Therefore, the battery monitoring device 100 can reduce costs. In addition, the battery monitoring device 100 can extend the cruising range due to weight reduction.
[0071] (Variation 1) Using Figure 7, the wiring board 10a of Modification 1 will be explained. The battery monitoring device 100 is equipped with a wiring board 10a in which a notch 14 is provided in only one place. In other words, the battery monitoring device 100 is equipped with only one connector 30. Even with this, the battery monitoring device 100 can achieve the same effects as described above.
[0072] Furthermore, this embodiment employs a notch 14, which is a recessed portion of the longitudinal side surface S3, extending from the substrate surface S1 to the substrate back surface S2. In other words, in the battery monitoring device 100, with the connector 30 mounted on the wiring board 10, the wiring board 10 is not provided in the region of the connector case 33 facing the Z direction. However, this disclosure is not limited thereto.
[0073] The battery monitoring device 100 can also be used with a concave notch 14 that does not extend from the substrate surface S1 to the substrate back surface S2. In other words, the notch 14 is a portion that has an opening along the substrate surface S1 and an opening along the longitudinal side surface S3, and is closed on the substrate back surface S2 side. In this case, with the connector 30 mounted on the wiring board 10, a part of the wiring board 10 will be provided in the region of the connector case 33 facing the Z direction. Even with this configuration, the battery monitoring device 100 can be made smaller in size in the thickness direction. Furthermore, the battery monitoring device 100 can also be positioned with the connector case 33 in contact with a part of the wiring board 10 provided in the region facing the Z direction, and the connector case 33 can be placed in the notch 14. This improves the mounting strength of the connector 30 to the wiring board 10.
[0074] This disclosure is described in accordance with embodiments, but it is understood that this disclosure is not limited to such embodiments or structures. This disclosure also includes various modifications and variations within the scope of equivalents. In addition, while various combinations and forms are shown in this disclosure, other combinations and forms that include one, more, or fewer of those elements also fall within the scope and idea of this disclosure. (Disclosure of technical ideas) This specification discloses several technical concepts, as listed in the following paragraphs. Some paragraphs are written in a multiple dependent form, where subsequent paragraphs optionally refer to preceding paragraphs. Furthermore, some paragraphs are written in a multiple dependent form, referring to other multiple dependent forms. These paragraphs written in multiple dependent forms define several technical concepts. (Technical thought 1) A battery monitoring device that monitors the status of batteries installed in a vehicle, A wiring board (10) on which a portion of the wiring (12) is provided on one side (S1), Circuit components (21, 22) surface-mounted on one surface and connected to the wiring, The connector member (30) electrically connects the wiring board and at least the battery, and includes a terminal (31) connected to a land (13a) which is part of the wiring provided on one surface, and a housing (33) on which the terminal is provided. The aforementioned wiring board has a recess (14) on a part of its side that is lower than the surrounding area, and at least a part of the housing is positioned in the recess, in a battery monitoring device. (Technical thought 2) The battery monitoring device according to technical concept 1, wherein the connector member is positioned such that the bottom surface (S12) of the housing is located at the same position as the opposite surface (S2) of the wiring board in the thickness direction of the wiring board. (Technical Thought 3) The wiring board has, as its side surfaces, short side surfaces (S4, S6) that are aligned with the short direction of one surface, and long side surfaces (S3, S5) that are aligned with the long direction of one surface and have the recess provided therein. A battery monitoring device according to technical concept 1 or 2, wherein at least a portion of the circuit components are arranged in a narrow region (OA) adjacent to the recess in the short direction on the aforementioned surface. (Technical Thought 4) The aforementioned battery supplies power to the electric motor that drives the vehicle, The battery monitoring device according to technical concept 3, wherein the circuit component has the function of monitoring the voltage of the battery. (Technical Thought 5) The battery monitoring device according to technical concept 3 or 4, wherein the wiring board is curved such that one side is convex. (Technical Thought 6) The battery monitoring device according to technical concept 3 or 4, wherein the circuit components and connector members are connected to the wiring by reflow soldering. (Technical Thought 7) The battery monitoring device according to any one of technical concepts 1 to 6, wherein the wiring board has multiple recesses on its side surface, and the housing is arranged in each recess. (Technical Thought 8) Furthermore, the device includes a base (41) on which the wiring board is fixed, and a cover (42) attached to the base, which together with the base forms a housing space for the wiring board. The battery monitoring device according to any one of technical concepts 1 to 7, wherein the wiring board is provided with a fixing portion (15) to the base at a position that sandwiches the recess. (Technical Thought 9) The battery monitoring device according to any one of technical concepts 1 to 8, wherein the wiring board is arranged such that the short side of one surface is aligned with the left-right direction of the vehicle, the long side of one surface is aligned with the front-rear direction of the vehicle, and the wiring board is arranged between a plurality of batteries arranged in the left-right direction. (Technical Thought 10) The aforementioned wiring board has fixing lands (13b) provided around the recess on one surface, The battery monitoring device according to any one of technical concepts 1 to 8, wherein the connector member has a fixing terminal (32) provided on the side wall of the housing, and the fixing terminal is connected to the fixing land. [Explanation of symbols]
[0075] 10, 10a…Wiring board, 11…Insulating board, 12…Wiring, 13a…Mounting land, 13b…Fixing land, 14…Notch, 15…Fixing hole, 16…Solder, 21…Battery monitoring IC, 21a…Element terminal, 22…Circuit element, 30…Connector, 31…Terminal, 32…Fixing member, 33…Connector case, 34…Insertion opening, 41…Base, 42…Cover, 100…Battery monitoring device, 200…Battery module, 300…Battery pack, S1…Board surface, S2…Board back, S11…Connector surface, S12…Connector back, OA…Opposite region, CL…Centerline
Claims
1. A battery monitoring device that monitors the status of batteries installed in a vehicle, A wiring board (10) on which a portion of the wiring (12) is provided on one side (S1), Circuit components (21, 22) surface-mounted on one surface and connected to the wiring, The connector member (30) electrically connects the wiring board and at least the battery, and comprises a terminal (31) connected to a land (13a) which is part of the wiring provided on one surface, and a housing (33) on which the terminal is provided. The aforementioned wiring board has a recess (14) on a part of its side that is lower than the surrounding area, and at least a part of the housing is placed in the recess. The aforementioned circuit component includes other circuit elements and a battery monitoring IC that is larger than the other circuit elements. The wiring board has, as its side surfaces, short side surfaces (S4, S6) that are aligned with the short direction of one surface, and long side surfaces (S3, S5) that are aligned with the long direction of one surface and have the recess provided therein. A battery monitoring device in which the battery monitoring IC is arranged in a narrow region (OA) adjacent to the recess in the short direction on one surface.
2. The battery monitoring device according to claim 1, wherein the connector member is positioned such that the bottom surface (S12) of the housing is located at the same position as the opposite surface (S2) of the wiring board in the thickness direction of the wiring board.
3. The aforementioned battery supplies power to the electric motor that drives the vehicle, The battery monitoring device according to claim 1, wherein the circuit component has a function of monitoring the voltage of the battery.
4. The battery monitoring device according to claim 1 or 3, wherein the wiring board is curved such that one side is convex.
5. The battery monitoring device according to claim 1 or 3, wherein the circuit components and the connector members are connected to the wiring by reflow soldering.
6. The battery monitoring device according to claim 1 or 2, wherein the wiring board has multiple recesses on its side surface, and the housing is arranged in each recess.
7. Furthermore, the device includes a base (41) on which the wiring board is fixed, and a cover (42) attached to the base and together with the base forming a housing space for the wiring board. The battery monitoring device according to claim 1 or 2, wherein the wiring board is provided with a fixing portion (15) to the base at a position that sandwiches the recess.
8. The battery monitoring device according to claim 1 or 2, wherein the wiring board is arranged such that the short side of one surface is aligned with the left-right direction of the vehicle, the long side of one surface is aligned with the front-rear direction of the vehicle, and the wiring board is arranged between a plurality of batteries arranged in the left-right direction.
9. The aforementioned wiring board has fixing lands (13b) provided around the recess on one surface, The battery monitoring device according to claim 1 or 2, wherein the connector member has a fixing terminal (32) provided on the side wall of the housing, and the fixing terminal is connected to the fixing land.