Battery management system and battery management method

Abstract

To shorten the time required for wireless communication processing.SOLUTION: A battery management system includes a plurality of monitoring devices and a control device. The monitoring devices acquire and monitor battery monitoring information including information indicating the state of batteries. The control device wirelessly communicates with the plurality of monitoring devices and performs predetermined processing based on the battery monitoring information. The control device and each of the monitoring devices perform, as wireless communication processing, connection processing, and periodic communication processing for periodically transmitting the battery monitoring information. The control device performs the wireless communication processing with the plurality of monitoring devices according to a predetermined priority.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] TECHNICAL FIELD The disclosure herein relates to a battery management system and a battery management method. [Background technology]

[0002] Patent Document 1 discloses a battery management system. The contents of the prior art document are incorporated by reference as explanations of the technical elements in this specification. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 8,399,115 Summary of the Invention [Problem to be solved by the invention]

[0004] In a battery management system using wireless communication, for example, wireless communication is performed between a control device and each of multiple monitoring devices. Therefore, for example, at startup, the connection processing timings of multiple monitoring devices may overlap, potentially lengthening the connection processing time due to radio wave interference. Furthermore, since a monitoring device that has completed connection processing transitions to periodic communication processing, there is a risk that the connection processing time of a monitoring device that has not yet completed connection processing may be extended due to communication waits. If the amount of data from other monitoring devices is large, periodic communication processing may not be executed, potentially lengthening the time until the next periodic communication processing is executed. Thus, there is a risk that the time required for wireless communication processing may be extended. In the above-mentioned respects and in other respects not mentioned, further improvements are required for battery management systems and battery management methods.

[0005] One disclosed object is to provide a battery management system and a battery management method that can reduce the time required for wireless communication processing. [Means for solving the problem]

[0006] The battery management system disclosed herein comprises: a plurality of monitoring devices (30) disposed in a housing (50) that houses the batteries (20, 21, 22), and configured to acquire and monitor battery monitoring information including information indicating the state of the batteries; a control device (40) that wirelessly communicates with the plurality of monitoring devices and executes predetermined processing based on the battery monitoring information; the control device and each of the plurality of monitoring devices execute, as a wireless communication process, a wireless communication connection process and, after the connection process is completed, a periodic communication process in which the monitoring device periodically transmits battery monitoring information to the control device; The control device executes wireless communication processing with the plurality of monitoring devices in accordance with a predetermined priority order.

[0007] According to the disclosed battery management system, wireless communication processing between the control device and multiple monitoring devices is performed according to a predetermined priority order, which reduces the time required for wireless communication processing compared to wireless communication without a priority order.

[0008] The battery management method disclosed herein comprises: A method for managing batteries (20, 21, 22) by wirelessly communicating between a plurality of monitoring devices (30) that are arranged in a housing (50) that houses the batteries (20, 21, 22) and that acquire and monitor battery monitoring information including information indicating the state of the batteries, and a control device (40) that executes predetermined processing based on the battery monitoring information, comprising: The control device and each of the plurality of monitoring devices perform wireless communication processing as follows: Executes wireless communication connection processing, After the connection process is completed, the monitoring device executes a periodic communication process in which the monitoring device periodically transmits battery monitoring information to the control device; The control device executes wireless communication processing with the plurality of monitoring devices in accordance with a predetermined priority order.

[0009] According to the disclosed battery management method, wireless communication processing between a control device and multiple monitoring devices is performed according to a predetermined priority order, which reduces the time required for wireless communication processing compared to wireless communication without a priority order.

[0010] The various aspects disclosed in this specification employ different technical means to achieve their respective objectives. The reference numerals in parentheses in the claims and in this section are intended to exemplify correspondences with the following embodiments and are not intended to limit the technical scope. The objectives, features, and advantages disclosed in this specification will become more apparent by reference to the following detailed description and the accompanying drawings. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing a vehicle equipped with a battery pack. [Figure 2] FIG. 2 is a perspective view showing a schematic configuration of a battery pack. [Figure 3] FIG. 2 is a plan view showing the battery pack. [Figure 4] 1 is a block diagram showing a configuration of a battery management system according to a first embodiment. [Figure 5] 10 is a timing chart showing an example of wireless communication at startup. [Figure 6] 4 is a flowchart showing a process executed by the control device at startup. [Figure 7] 10 is a flowchart showing a process executed by the monitoring device at startup. [Figure 8] FIG. 10 is a diagram showing the flow of wireless communication at startup in a reference example. [Figure 9] FIG. 4 is a diagram showing the flow of wireless communication at startup in the first embodiment. [Figure 10] 10 is a timing chart showing an example of wireless communication at the time of reconnection in a battery management system according to a second embodiment. [Figure 11] 10 is a flowchart showing a process executed by the control device at the time of reconnection. [Figure 12] 10 is a flowchart showing a process executed by a monitoring device to be connected; [Figure 13] 10 is a flowchart showing a process executed by a non-target monitoring device. [Figure 14] 10 is a timing chart showing connection processing according to priority in a battery management system according to a third embodiment. [Figure 15] 4 is a flowchart showing a process executed by a control device. [Figure 16] 10 is a flowchart showing a process executed by a monitoring device that is a priority target. [Figure 17] 10 is a flowchart showing a process executed by a non-target monitoring device. [Figure 18] FIG. [Figure 19] FIG. [Figure 20] FIG. [Figure 21] FIG. [Figure 22] 11 is a timing chart showing periodic communication processing according to priority in a battery management system according to a third embodiment. [Figure 23] 4 is a flowchart showing a process executed by a control device. [Figure 24] 10 is a flowchart showing a process executed by a monitoring device that is a priority target. [Figure 25] 10 is a flowchart showing a process executed by a non-target monitoring device. [Figure 26] FIG. 10 is a diagram showing an inspection system including a battery management system according to a fifth embodiment. [Figure 27] 10 is a flowchart showing a process executed by the inspection device. [Figure 28] 10 is a flowchart showing a process executed by the monitoring device. [Figure 29] FIG. 10 is a diagram showing the flow of wireless communication between an inspection device and a plurality of monitoring devices. [Figure 30] FIG. 10 is a block diagram showing a modified example of the battery management system. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, several embodiments will be described with reference to the drawings. Note that in each embodiment, corresponding components are designated by the same reference numerals, and redundant description may be omitted. When only a portion of the configuration is described in each embodiment, the configuration of another embodiment previously described may be applied to the remaining portion of the configuration. Furthermore, in addition to the combinations of configurations explicitly stated in the description of each embodiment, configurations of several embodiments may be partially combined together even if not explicitly stated, provided that there is no particular problem with the combination.

[0013] (First embodiment) First, the configuration of a vehicle equipped with a battery management system according to this embodiment, particularly a vehicle related to a battery pack equipped with the battery management system, will be described with reference to Fig. 1. Fig. 1 is a diagram showing a schematic configuration of a vehicle. The vehicle is an electrically powered vehicle such as an electric vehicle (BEV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV). The battery management system can also be applied to moving objects other than vehicles, such as aircraft such as drones, ships, construction machinery, and agricultural machinery. The battery management system can also be applied to stationary batteries (storage batteries) for home or commercial use.

[0014] <Vehicle> As shown in Fig. 1, a vehicle 10 includes a battery pack (BAT) 11, a PCU 12, an MG 13, and an ECU 14. PCU is an abbreviation for Power Control Unit, MG is an abbreviation for Motor Generator, and ECU is an abbreviation for Electronic Control Unit.

[0015] The battery pack 11 includes a battery pack 20, which will be described later, and provides a chargeable and dischargeable DC voltage source. The battery pack 11 supplies power to electrical loads of the vehicle 10. For example, the battery pack 11 supplies power to the MG 13 through the PCU 12. The battery pack 11 is charged through the PCU 12. The battery pack 11 is sometimes referred to as a main battery.

[0016] 1, the battery pack 11 is disposed in the front compartment of the vehicle 10. The battery pack 11 may also be disposed in the rear compartment, under the seat, under the floor, etc. For example, in the case of a hybrid vehicle, the compartment in which the engine is disposed may be referred to as the engine compartment, engine room, etc.

[0017] The temperature of the battery pack 11 is regulated by the wind generated when the vehicle 10 is running or by cooling air supplied from a fan mounted on the vehicle 10. The temperature of the battery pack 11 may also be regulated by a cooling liquid circulating inside the vehicle 10. The temperature regulation described above suppresses excessive temperature changes in the battery pack 11. Note that the battery pack 11 may simply be connected to a member with a large heat capacity, such as the body of the vehicle 10, in a manner that allows thermal conduction.

[0018] The PCU 12 performs bidirectional power conversion between the battery pack 11 and the MG 13 in accordance with a control signal from the ECU 14. The PCU 12 is sometimes referred to as a power converter. The PCU 12 may include an inverter and a converter. The converter is disposed in the current path between the battery pack 11 and the inverter. The converter has a function of stepping up and down a DC voltage. The inverter converts the DC voltage stepped up by the converter into an AC voltage, for example, a three-phase AC voltage, and outputs it to the MG 13. The inverter converts the power generated by the MG 13 into a DC voltage and outputs it to the converter.

[0019] The MG 13 is an AC rotating electric machine, for example, a three-phase AC synchronous motor with a permanent magnet embedded in the rotor. The MG 13 functions as a drive source for the vehicle 10, i.e., as an electric motor. The MG 13 is driven by the PCU 12 to generate rotational driving force. The driving force generated by the MG 13 is transmitted to the drive wheels. The MG 13 functions as a generator when the vehicle 10 is braked, and performs regenerative power generation. The power generated by the MG 13 is supplied to the battery pack 11 via the PCU 12 and stored in the battery pack 20 in the battery pack 11.

[0020] The ECU 14 includes a computer equipped with a processor, memory, an input / output interface, and a bus connecting these components. The processor is hardware for performing arithmetic processing. The processor includes, for example, a CPU as a core. CPU is an abbreviation for Central Processing Unit. The memory is a non-transient, tangible storage medium that non-temporarily stores computer-readable programs, data, and the like. The memory stores various programs executed by the processor.

[0021] The ECU 14 acquires information about the battery pack 20 from the battery pack 11, for example, and controls the PCU 12 to control the driving of the MG 13 and the charging and discharging of the battery pack 11. The ECU 14 may acquire information about the voltage, temperature, current, SOC, SOH, etc. of the battery pack 20 from the battery pack 11. The ECU 14 may acquire battery information such as the voltage, temperature, and current of the battery pack 20 to calculate the SOC and SOH. SOC is an abbreviation for State Of Charge. SOH is an abbreviation for State Of Health.

[0022] The processor of the ECU 14 executes a plurality of instructions contained in a PCU control program stored in a memory, for example. In this way, the ECU 14 configures a plurality of functional units for controlling the PCU 12. In this way, the program stored in the memory causes the processor to execute a plurality of instructions, thereby configuring a plurality of functional units. The ECU 14 is sometimes referred to as an EVECU.

[0023] <Battery pack> Next, an example of the configuration of the battery pack 11 will be described with reference to Fig. 2 and Fig. 3. Fig. 2 is a perspective view schematically showing the inside of the battery pack 11. In Fig. 2, the housing is indicated by a two-dot chain line. Fig. 3 is a plan view showing the top surface of each battery stack.

[0024] As shown in FIG. 2, the battery pack 11 includes a battery pack 20, a plurality of monitoring devices 30, a control device 40, and a housing 50. Hereinafter, of the surfaces of the housing 50, which is a substantially rectangular parallelepiped, the longitudinal direction of the surface on which the battery pack 11 is mounted on the vehicle 10 is referred to as the X direction, and the lateral direction of the surface is referred to as the Y direction. In FIG. 2, the bottom surface is the mounting surface. The up-down direction perpendicular to the mounting surface is referred to as the Z direction. The X direction, Y direction, and Z direction are orthogonal to one another. In this embodiment, the left-right direction of the vehicle 10 corresponds to the X direction, the front-rear direction corresponds to the Y direction, and the up-down direction corresponds to the Z direction. The arrangements shown in FIGS. 2 and 3 are merely examples, and the battery pack 11 may be arranged in any manner relative to the vehicle 10.

[0025] The battery pack 20 has a plurality of battery stacks 21 arranged side by side in the X direction. The battery stacks 21 may also be referred to as battery blocks, battery modules, etc. The battery pack 20 is configured by connecting a plurality of battery stacks 21 in series and / or parallel. In this embodiment, the plurality of battery stacks 21 are connected in series.

[0026] Each battery stack 21 has a plurality of battery cells 22. The plurality of battery cells 22 are housed in a case (not shown). This fixes the relative positions of the plurality of battery cells 22. The case is made of metal or resin. If the case is made of metal, an electrically insulating member may be interposed partially or entirely between the wall of the case and the battery cells 22.

[0027] The form of the fixing member is not particularly limited as long as it can fix the relative positions of the multiple battery cells 22. For example, it is also possible to adopt a configuration in which the multiple battery cells 22 are restrained by a strip-shaped band. In this case, separators may be interposed between the multiple battery cells 22 to maintain a distance between them.

[0028] The battery stack 21 has a plurality of battery cells 22 connected in series. The battery stack 21 of this embodiment is configured by connecting a plurality of battery cells 22 arranged side by side in the Y direction in series. The assembled battery 20 provides the DC voltage source. The assembled battery 20, the battery stack 21, and the battery cells 22 correspond to a battery.

[0029] The battery cell 22 is a secondary battery that generates an electromotive force through a chemical reaction. The secondary battery may be a lithium-ion secondary battery, a nickel-metal hydride secondary battery, an organic radical battery, or the like. A lithium-ion secondary battery is a secondary battery that uses lithium as a charge carrier. Secondary batteries that can be used for the battery cell 22 include not only secondary batteries with liquid electrolytes, but also so-called all-solid-state batteries that use solid electrolytes.

[0030] Each battery cell 22 has a power generating element and a battery case that houses the power generating element. As shown in Fig. 3, the battery case of each battery cell 22 is formed in a flat shape. The battery case has a total of four side faces: two end faces aligned in the Z direction, two aligned in the X direction, and two aligned in the Y direction. The battery case of this embodiment is made of metal.

[0031] The battery cells 22 are stacked so that the side surfaces of the battery cases are in contact with each other in the Y direction. Each battery cell 22 has a positive terminal 25 and a negative terminal 26 at both ends in the X direction that protrude in the Z direction, more specifically in the Z+ direction indicating upward. The Z-direction positions of the protruding end faces of these positive terminals 25 and negative terminals 26 are the same for each battery cell 22. The battery cells 22 are stacked so that the positive terminals 25 and negative terminals 26 are alternately arranged in the Y direction.

[0032] Linear busbar units 23 are arranged on both ends in the X direction on the top surface of each battery stack 21. The busbar units 23 are arranged on both ends in the X direction of the protruding end faces of the positive electrode terminals 25 and negative electrode terminals 26 of the multiple battery cases. In other words, a pair of busbar units 23 are arranged in each battery stack 21.

[0033] Each busbar unit 23 has a plurality of busbars 24 that electrically connect positive terminals 25 and negative terminals 26 that are alternately arranged in the Y direction, and a busbar cover 27 that covers the plurality of busbars 24. The busbars 24 are plates made of a metal with good conductivity, such as copper or aluminum. The busbars 24 electrically connect the positive terminals 25 and negative terminals 26 of battery cells 22 that are adjacent to each other in the Y direction. As a result, in each battery stack 21, the plurality of battery cells 22 are connected in series.

[0034] With this connection structure, one of the two battery cells 22 located at the ends of the multiple battery cells 22 aligned in the Y direction in each battery stack 21 has the highest potential, and the other has the lowest potential. A predetermined wire is connected to at least one of the positive electrode terminal 25 of the battery cell 22 with the highest potential and the negative electrode terminal 26 of the battery cell 22 with the lowest potential.

[0035] 2, the multiple battery stacks 21 are aligned in the X direction. In one of two battery stacks 21 adjacent to each other in the X direction, the positive electrode terminal 25 of the battery cell 22 with the highest potential is connected to the negative electrode terminal 26 of the battery cell 22 with the lowest potential in the other battery stack 21 via a predetermined wiring. In this way, the multiple battery stacks 21 are connected in series.

[0036] With this connection structure, one of the two battery stacks 21 located at the ends of the multiple battery stacks 21 lined up in the X direction becomes the highest potential side, and the other becomes the lowest potential side. In the battery stack 21 on the highest potential side, an output terminal is connected to the positive electrode terminal 25 of the battery cell 22 with the highest potential among the multiple battery cells 22. In the battery stack 21 on the lowest potential side, an output terminal is connected to the negative electrode terminal 26 of the battery cell 22 with the lowest potential among the multiple battery cells 22. These two output terminals are connected to electrical equipment installed in the vehicle 10, such as the PCU 12.

[0037] Two battery stacks 21 adjacent to each other in the X direction do not necessarily have to be electrically connected via a predetermined wiring. Any two of the battery stacks 21 arranged in the X direction may be electrically connected via a predetermined wiring. Furthermore, the positions in the Y direction of the positive electrode terminal 25 and the negative electrode terminal 26 electrically connected via a predetermined wiring may be equal or different. That is, the positive electrode terminal 25 and the negative electrode terminal 26 may at least partially face each other in the X direction, or may not face each other at all. At least a portion of one of the positive electrode terminal 25 and the negative electrode terminal 26 may be located in the projection area of ​​the other in the X direction, or may not be located at all.

[0038] The bus bar cover 27 is made of an electrically insulating material such as resin. The bus bar cover 27 is provided linearly from one end of the battery stack 21 to the other end along the Y direction so as to cover the multiple bus bars 24. The bus bar cover 27 may have a partition wall. The partition wall improves the insulation between two bus bars 24 adjacent to each other in the Y direction.

[0039] The monitoring device 30 is provided individually for each of the plurality of battery stacks 21. As shown in FIG. 2 , the monitoring device 30 is disposed between a pair of busbar units 23 in each battery stack 21. The monitoring device 30 faces the protruding end faces of the positive electrode terminal 25 and the negative electrode terminal 26 of the battery case in the Z direction. The monitoring device 30 and these end faces may be spaced apart in the Z direction, or may face each other and be in contact with each other in the Z direction. An intervening object such as an insulating sheet may be provided between the monitoring device 30 and these end faces.

[0040] The monitoring device 30 is fixed to the busbar unit 23 with screws or the like. As will be described later, the monitoring device 30 is configured to be able to communicate wirelessly with the control device 40. An antenna 37 (described later) provided in the monitoring device 30 is arranged so as not to overlap with the busbar unit 23 in the Z direction, that is, so as to protrude further than the busbar unit 23 in the Z direction.

[0041] To avoid interference with wireless communication, a non-magnetic material may be used as the material for connecting members such as screws that connect the monitoring device 30 and the busbar unit 23. In addition to the screws, non-magnetic materials may also be used as the constituent materials for components that do not necessarily need to be magnetic, among the components provided in the battery stack 21.

[0042] In this embodiment, the multiple monitoring devices 30 are lined up in the X direction. The positions of the multiple monitoring devices 30 in the Y direction are the same. Due to the configuration described above, the distance between the multiple monitoring devices 30 is prevented from increasing.

[0043] The control device 40 is attached to the outer surface of the battery stack 21 located at one end in the X direction. The control device 40 is configured to be able to wirelessly communicate with each monitoring device 30. An antenna 42 (described later) provided in the control device 40 is disposed at approximately the same height in the Z direction as the antenna 37 of the monitoring device 30. In other words, the antenna 42 of the control device 40 is disposed so as to protrude further than the busbar unit 23 in the Z direction.

[0044] In the battery pack 11, the monitoring device 30 and the control device 40 provide a battery management system 60, which will be described later.

[0045] To prevent the battery pack 11 from becoming a source of electromagnetic noise, it is necessary to prevent radio waves from leaking outside the space (communication space) where wireless communication is performed between the monitoring device 30 and the control device 40. Conversely, to prevent this wireless communication from being obstructed, it is necessary to prevent electromagnetic noise from entering the communication space.

[0046] For this reason, the housing 50 has the ability to reflect electromagnetic waves, for example. The housing 50 is provided with the following materials, examples of which are shown below, in order to reflect electromagnetic waves. For example, the housing 50 is provided with a magnetic material such as metal. The housing 50 is provided with a resin material and a magnetic material covering the surface. The housing 50 is provided with a resin material and a magnetic material embedded inside the resin material. The housing 50 is provided with carbon fiber. The housing 50 may have the ability to absorb electromagnetic waves instead of the ability to reflect electromagnetic waves.

[0047] The housing 50 may have a hole that communicates with the storage space inside and the space outside (external space). The hole is defined by a connecting surface between the inner and outer surfaces of the housing 50. This hole is used for ventilation, for extracting power lines, for extracting signal lines, etc. In the case of a configuration with a hole, a cover may be provided for the hole. The cover prevents communication between the storage space and the external space. The cover may cover the entire hole, or may cover only a portion of the hole.

[0048] The cover portion is provided, for example, on any one of the inner surface, outer surface, and connecting surface of the housing 50. The cover portion may be disposed opposite the hole in a manner that covers the hole without being provided on any of the inner surface, outer surface, and connecting surface. When the cover portion and the hole are spaced apart, the distance between them is shorter than the length of the hole. The length of the hole is either the distance between the inner surface and the outer surface or the distance in a direction perpendicular to this distance.

[0049] The covering portion is, for example, a connector, an electromagnetic shielding member, a sealing material, etc. The covering portion comprises the following materials, as examples: The covering portion comprises a magnetic material, such as metal; The covering portion comprises a resin material and a magnetic material covering the surface of the resin material; The covering portion comprises a resin material and a magnetic material embedded inside the resin material; The covering portion comprises carbon fiber; The covering portion includes a resin material.

[0050] The hole in the housing 50 may be covered by at least one of the elements housed in the housing space of the housing 50. The distance between this housed object and the hole is shorter than the length of the hole. Furthermore, power lines and signal lines may be arranged across the housing space and the external space while being held by an electrically insulating member that forms part of the wall of the housing 50.

[0051] <Battery management system> Next, a schematic configuration of the battery management system will be described with reference to Fig. 4. Fig. 4 is a block diagram showing the configuration of the battery management system.

[0052] As shown in Fig. 4, the battery management system 60 includes multiple monitoring devices (SBMs) 30 and a control device (ECU) 40. Hereinafter, the monitoring devices may be referred to as SBMs. The control devices 40 may be referred to as battery ECUs, BMUs, etc. BMU is an abbreviation for Battery Management Unit. The battery management system 60 is a system that manages batteries using wireless communication. This wireless communication uses a frequency band used for short-range communication, such as the 2.4 GHz band or the 5 GHz band.

[0053] The battery management system 60 employs one-to-one communication or network communication depending on the number of nodes for wireless communication by the monitoring device 30 and / or the control device 40. The number of nodes may change depending on the hibernation state of the monitoring device 30 and / or the control device 40. When the number of nodes is two, the battery management system 60 employs one-to-one communication. When the number of nodes is three or more, the battery management system 60 employs network communication. One form of network communication is star communication, in which one node is designated as a master and the remaining nodes are designated as slaves, and wireless communication is performed between the master and all of the slaves. Another form of network communication is chain communication, in which multiple nodes are connected in series and wireless communication is performed. Another form of network communication is mesh communication.

[0054] The battery management system 60 further includes a sensor 70. The sensor 70 includes a physical quantity detection sensor and a discrimination sensor that detect the physical quantity of each battery cell 22. The physical quantity detection sensor includes, for example, a voltage sensor, a temperature sensor, a current sensor, and the like.

[0055] The voltage sensor includes detection wiring connected to the bus bar 24. The voltage sensor detects the voltage (cell voltage) of each of the plurality of battery cells 22. The discrimination sensor determines whether or not the correct battery is installed.

[0056] The temperature sensors are selectively provided in some of the plurality of battery cells 22 included in the battery stack 21. The temperature sensors detect the temperatures (cell temperatures) of the selected battery cells 22 as the temperature of the battery stack 21. Of the plurality of battery cells 22 included in one battery stack 21, the temperature sensors are provided in the battery cell 22 expected to have the highest temperature, the battery cell 22 expected to have the lowest temperature, the battery cell 22 expected to have an intermediate temperature, and the like. The number of temperature sensors for one battery stack 21 is not particularly limited.

[0057] A current sensor is provided in each of the plurality of battery stacks 21. The current sensor detects a current (cell current) that flows commonly through each of the plurality of series-connected battery cells 22 and the plurality of series-connected battery stacks 21. In this embodiment, all of the battery stacks 21 are connected in series, so one current sensor is provided, but the number of current sensors is not limited to this example.

[0058] <Monitoring device> First, the monitoring device 30 will be described. The configuration of each monitoring device 30 is the same. The monitoring device 30 includes a power supply circuit (PSC) 31, a multiplexer (MUX) 32, a monitoring IC (MIC) 33, a microcomputer (MC) 34, a wireless IC (WIC) 35, a front-end circuit (FE) 36, and an antenna (ANT) 37. Communication between the elements within the monitoring device 30 is performed via wires.

[0059] The power supply circuit 31 generates operating power for other circuit elements included in the monitoring device 30, using the voltage supplied from the battery stack 21. In this embodiment, the power supply circuit 31 includes power supply circuits 311, 312, and 313. The power supply circuit 311 generates a predetermined voltage using the voltage supplied from the battery stack 21 and supplies it to the monitoring IC 33. The power supply circuit 312 generates a predetermined voltage using the voltage generated by the power supply circuit 311 and supplies it to the microcomputer 34. The power supply circuit 313 generates a predetermined voltage using the voltage generated by the power supply circuit 311 and supplies it to the wireless IC 35.

[0060] The multiplexer 32 is a selection circuit that selects one of at least some of the detection signals of the multiple sensors 70 provided in the battery pack 11 and outputs the selected signal. The multiplexer 32 selects (switches) the input in accordance with a selection signal from the monitoring IC 33 and outputs it as one signal.

[0061] The monitoring IC 33 senses (acquires) battery information such as cell voltage and cell temperature and transmits it to the microcomputer 34. For example, the monitoring IC 33 acquires cell voltage directly from a voltage sensor and acquires information such as cell temperature through the multiplexer 32. The monitoring IC 33 acquires cell voltage by correlating it with the value of any battery cell 22. In other words, it acquires cell voltage while distinguishing between cells. The cell current detected by the current sensor may be input to the monitoring IC 33 or may be input to the control device 40 via a wired connection.

[0062] The monitoring IC 33 is sometimes referred to as a cell monitoring circuit (CSC). CSC is an abbreviation for Cell Supervising Circuit. The monitoring IC 33 performs fault diagnosis on the circuitry of the monitoring device 30, including itself. That is, the monitoring IC 33 transmits battery monitoring information, including battery information and fault diagnosis information, to the microcomputer 34. The monitoring device 30 may store (preserve) the acquired battery monitoring information in a memory such as the microcomputer 34. When the monitoring IC 33 receives data requesting acquisition of battery monitoring information from the microcomputer 34, it senses the battery information and transmits the battery monitoring information, including the battery information, to the microcomputer 34. In addition to the examples described above, the battery monitoring information may also include information such as exhaust gas temperature, impedance, cell voltage equalization status, stack voltage, synchronization status with the control device 40, and the presence or absence of abnormalities in the detection wiring.

[0063] The microcomputer 34 is a microcomputer equipped with a processor (CPU), memory (ROM and RAM), an input / output interface, and a bus connecting these. The CPU executes various programs stored in the ROM while utilizing the temporary storage function of the RAM, thereby constructing multiple functional units. ROM is an abbreviation for Read Only Memory. RAM is an abbreviation for Random Access Memory.

[0064] The microcomputer 34 controls the schedule for sensing and self-diagnosis by the monitoring IC 33. The microcomputer 34 receives battery monitoring information transmitted from the monitoring IC 33 and transmits it to the wireless IC 35. The microcomputer 34 transmits data requesting acquisition of the battery monitoring information to the monitoring IC 33. For example, when the microcomputer 34 receives data requesting acquisition of the battery monitoring information transmitted from the wireless IC 35, the microcomputer 34 may transmit data requesting acquisition of the battery monitoring information to the monitoring IC 33. The microcomputer 34 may autonomously request acquisition of the battery monitoring information from the monitoring IC 33. For example, the microcomputer 34 may periodically request acquisition of the battery monitoring information from the monitoring IC 33.

[0065] The wireless IC 35 includes an RF circuit and a microcomputer (not shown) to transmit and receive data wirelessly. The microcomputer includes a memory. The wireless IC 35 has a transmission function that modulates transmission data and oscillates at the frequency of an RF signal. The wireless IC 35 has a reception function that demodulates received data. RF is an abbreviation for radio frequency.

[0066] The wireless IC 35 modulates the data including the battery monitoring information transmitted from the microcomputer 34 and transmits it to other nodes such as the control device 40 via the front-end circuit 36 ​​and the antenna 37. The wireless IC 35 adds data necessary for wireless communication, such as communication control information, to the transmission data including the battery monitoring information and transmits it. The data necessary for wireless communication includes, for example, an identifier (ID) and an error detection code. The wireless IC 35 controls the data size, communication format, schedule, error detection, etc. of wireless communication with other nodes.

[0067] The wireless IC 35 receives and demodulates data transmitted from other nodes via the antenna 37 and the front-end circuit 36. For example, when the wireless IC 35 receives data including a request to transmit battery monitoring information, it transmits the data including the battery monitoring information to other nodes in response to the request. The monitoring device 30 may transmit battery traceability information and / or manufacturing history information to other nodes in addition to the battery monitoring information described above. The battery traceability information may include, for example, the number of charge / discharge cycles, the number of failures, and the total charge / discharge time. The manufacturing history information may include, for example, the manufacturing date, location, manufacturer, serial number, and manufacturing number. The manufacturing history information is stored in a memory provided in the monitoring device 30. The monitoring device 30 may transmit the battery traceability information and / or the manufacturing history information to other nodes instead of the battery monitoring information.

[0068] The front-end circuit 36 ​​has a matching circuit for matching the impedance between the wireless IC 35 and the antenna 37, and a filter circuit for removing unnecessary frequency components.

[0069] The antenna 37 converts the electric signal into a radio wave and radiates it into space. The antenna 37 receives the radio wave propagating through space and converts it into an electric signal.

[0070] <Control device> Next, the control device 40 will be described with reference to Fig. 4. The control device 40 includes a power supply circuit (PSC) 41, an antenna (ANT) 42, a front-end circuit (FE) 43, a wireless IC (WIC) 44, a main microcomputer (MMC) 45, and a sub-microcomputer (SMC) 46. Communication between the elements within the control device 40 is performed via wires.

[0071] The power supply circuit 41 generates operating power for other circuit elements included in the control device 40, using voltage supplied from the battery (BAT) 15. The battery 15 is a DC voltage source separate from the battery pack 11 and mounted on the vehicle 10. The battery 15 is sometimes referred to as an auxiliary battery because it supplies power to auxiliary devices of the vehicle 10. In this embodiment, the power supply circuit 41 includes power supply circuits 411 and 412. The power supply circuit 411 generates a predetermined voltage using the voltage supplied from the battery 15 and supplies it to the main microcomputer 45 and the sub-microcomputer 46. To simplify the diagram, the electrical connection between the power supply circuit 411 and the sub-microcomputer 46 is omitted. The power supply circuit 412 generates a predetermined voltage using the voltage generated by the power supply circuit 411 and supplies it to the wireless IC 44.

[0072] The antenna 42 converts the electrical signal into a radio wave and radiates it into space. The antenna 42 receives the radio wave propagating through space and converts it into an electrical signal.

[0073] The front-end circuit 43 has a matching circuit for matching the impedance between the wireless IC 44 and the antenna 42, and a filter circuit for removing unnecessary frequency components.

[0074] The wireless IC 44 includes an RF circuit and a microcomputer (not shown) for wirelessly transmitting and receiving data. Like the wireless IC 35, the wireless IC 44 has transmitting and receiving functions. The wireless IC 44 receives and demodulates data transmitted from the monitoring device 30 via the antenna 42 and the front-end circuit 43. It then transmits the data, including battery monitoring information, to the main microcomputer 45. The wireless IC 44 receives and modulates the data transmitted from the main microcomputer 45, and transmits the data to the monitoring device 30 via the front-end circuit 43 and the antenna 42. The wireless IC 44 adds data necessary for wireless communication, such as communication control information, to the transmitted data and transmits it. The data necessary for wireless communication includes, for example, an identifier (ID) and an error detection code. The wireless IC 44 controls the data size, communication format, schedule, error detection, and other aspects of wireless communication between other nodes.

[0075] The main microcomputer 45 is a microcomputer equipped with a CPU, ROM, RAM, an input / output interface, and buses connecting these. The ROM stores various programs executed by the CPU. The main microcomputer 45 generates commands requesting predetermined processing from the monitoring device 30 and transmits transmission data including the commands to the wireless IC 44. The main microcomputer 45 generates, for example, a command requesting the transmission of battery monitoring information. The main microcomputer 45 may generate commands requesting the acquisition of battery monitoring information as well as the transmission of battery monitoring information. Requests described in this specification are sometimes referred to as instructions.

[0076] The main microcomputer 45 receives data including the battery monitoring information transmitted from the wireless IC 44 and executes predetermined processing based on the battery monitoring information. In this embodiment, the main microcomputer 45 acquires cell currents from current sensors and executes predetermined processing based on the battery monitoring information and the acquired cell currents. For example, the main microcomputer 45 executes processing to transmit the acquired battery monitoring information to the ECU 14. The main microcomputer 45 may calculate at least one of the internal resistance, open circuit voltage (OCV), SOC, and SOH of the battery cells 22 based on the battery monitoring information and transmit information including the calculated data to the ECU 14. OCV stands for Open Circuit Voltage.

[0077] The main microcomputer 45 performs a process of estimating the internal resistance and open-circuit voltage of the battery cell 22, for example, based on the cell voltage and cell current. The open-circuit voltage is the cell voltage according to the SOC of the battery cell 22. The open-circuit voltage is the cell voltage when no current is flowing. There is a difference between the open-circuit voltage and the cell voltage acquired by the monitoring device 30 due to a voltage drop according to the internal resistance and the cell current. The internal resistance changes according to the cell temperature. The lower the cell temperature, the larger the value of the internal resistance. The main microcomputer 45 performs a process of estimating the internal resistance and open-circuit voltage of the battery cell 22, for example, taking the cell temperature into account.

[0078] Based on the battery monitoring information, the main microcomputer 45 may instruct the execution of an equalization process to equalize the voltages of the battery cells 22. The main microcomputer 45 may acquire an IG signal from the vehicle 10 and execute the above-described process according to the driving state of the vehicle 10. Based on the battery monitoring information, the main microcomputer 45 may execute a process to detect abnormalities in the battery cells 22 or circuits, and may send abnormality detection information to the ECU 14.

[0079] The sub-microcomputer 46 is a microcomputer equipped with a CPU, ROM, RAM, an input / output interface, and a bus connecting these. The ROM stores various programs executed by the CPU. The sub-microcomputer 46 performs monitoring processing within the control device 40. For example, the sub-microcomputer 46 may monitor data between the wireless IC 44 and the main microcomputer 45. The sub-microcomputer 46 may monitor the status of the main microcomputer 45. The sub-microcomputer 46 may monitor the status of the wireless IC 44.

[0080] <Wireless communication at startup> An example of wireless communication at startup that is performed in accordance with priority will be described with reference to Figs. 5 to 7. Fig. 5 is a timing chart showing an example of wireless communication at startup. Fig. 5 shows the communication state between the control device 40 and each of the monitoring devices 30. Fig. 5 shows an example in which n (n≧4) monitoring devices 30 are provided. Fig. 6 is a flowchart showing the processing executed by the control device 40 at startup. Fig. 7 is a flowchart showing the processing executed by each of the monitoring devices 30 at startup. In the specification and drawings, the monitoring device 30 may be referred to as an SBM, and the control device 40 may be referred to as an ECU.

[0081] The battery management system 60 of this embodiment performs star-type network communication when the number of nodes is three or more. For example, the control device 40 performs wireless communication with each of the multiple monitoring devices 30. When the monitoring device 30 and the control device 40 are started up, they first perform a connection process. After the connection process is completed, they perform a periodic communication process to periodically send and receive battery monitoring information. The connection process (steps S12, S22) and periodic communication process (steps S15, S25) shown in Figs. 6 and 7, which will be described later, are the basic processes of wireless communication.

[0082] The start-up time refers to, for example, when operating power is supplied. In a configuration in which power is constantly supplied from the battery stack 21 or the battery 15, the start-up occurs during the manufacturing process of the vehicle 10 or after a part is replaced at a repair shop. The start-up time may also be when a start-up signal, such as an IG signal or an SMR ON signal, is supplied. For example, the start-up occurs when the IG signal is switched from OFF to ON by a user operation. SMR is an abbreviation for System Main Relay. The SMR is provided on the power line connecting the battery pack 11 and the PCU 12, and electrically connects the battery pack 11 and the PCU 12 when ON, and disconnects them when OFF. In this embodiment, the start-up occurs when the IG signal is switched from OFF to ON. The control device 40 executes a connection process with all monitoring devices 30 to be connected.

[0083] At time t1 shown in Fig. 5, operating power is supplied to the control device 40 and each of the multiple monitoring devices 30. Upon receiving the operating power, the control device 40 starts up (step S11) as shown in Fig. 6, and starts connection processing with the monitoring device 30 (step S12). Similarly, upon receiving the operating power, each of the multiple monitoring devices 30 starts up (step S21) as shown in Fig. 7, and starts connection processing with the control device 40 (step S22). As a result, the communication state switches from non-connected to connecting processing at time t1 as shown in Fig. 5.

[0084] The connection process includes at least a connection establishment process. In the connection establishment process, the control device 40 performs, for example, a scanning operation, and the monitoring device 30 performs an advertising operation. When the control device 40 detects an advertisement packet through the scanning operation, a connection is established between the control device 40 and the monitoring device 30 that transmitted the advertisement packet. Note that the monitoring device 30 may perform the scanning operation, and the control device 40 may perform the advertising operation. The connection process may further include a pairing process. The pairing process is a process for performing encrypted data communication, and is performed after the connection establishment process. The pairing process includes a process for exchanging unique information. This enables encryption using the unique information.

[0085] Next, the control device 40 determines whether or not the connection process with one of the monitoring devices 30 has been completed (step S13), as shown in Fig. 6. Similarly, the monitoring device 30 determines whether or not the connection process with the control device 40 has been completed (step S23), as shown in Fig. 7.

[0086] Here, one of the monitoring devices 30 refers to one of the monitoring devices 30 for which the connection process has not been completed. As described above, when the connection is established and the pairing process is completed, the connection process is completed. If the connection process with any of the monitoring devices 30 has not been completed, the control device 40 returns to step S12. Similarly, if the connection process with the control device 40 has not been completed, the monitoring device 30 returns to step S22. The monitoring device 30 periodically transmits advertisement packets until the connection is established.

[0087] When the connection process with one of the monitoring devices 30 is completed, the control device 40 transmits a completion notification to the corresponding monitoring device 30. Upon receiving the completion notification, the monitoring device 30 determines in step S23 that the connection process with the control device 40 is completed. This completes the connection process between the control device 40 and one of the monitoring devices 30.

[0088] 5, time t2 is the connection completion time of the monitoring device 30 (SBM1) that completed the connection process first, and time t3 is the connection completion time of the monitoring device 30 (SBM2) that completed the connection process second.

[0089] If it is determined in step S13 that the connection process with one of the monitoring devices 30 has been completed, the control device 40 then determines whether the connection process with all of the monitoring devices 30 with which it is communicating has been completed (step S14). If it is determined in step S14 that the connection process with all of the monitoring devices 30 has not been completed, the process returns to step S12 and continues the connection process with the incomplete monitoring devices 30. Once the connection process with all of the monitoring devices 30 has been completed, the control device 40 then executes periodic communication processing (step S15). As the periodic communication processing is executed, the control device 40 transmits a signal to all of the monitoring devices 30 instructing them to transition to periodic communication processing.

[0090] When the monitoring device 30 determines in step S23 that the connection process with the control device 40 is complete, it then determines whether or not to transition to periodic communication processing (step S24). The monitoring device 30 determines that transition to periodic communication processing is not possible and repeats the processing of step S24 until it receives a transition instruction signal from the control device 40. When the monitoring device 30 receives a transition instruction signal from the control device 40, it determines that transition to periodic communication processing is possible and executes periodic communication processing (step S25).

[0091] As described above, the control device 40 and the multiple monitoring devices 30 do not execute periodic communication processing until connection processing between the control device 40 and all of the monitoring devices 30 is complete. Time t4 shown in Figure 5 is the completion time for the nth monitoring device 30 (SBMn), that is, the last monitoring device 30 to complete connection processing. As shown in Figure 5, the control device 40 and the multiple monitoring devices 30 do not execute periodic communication processing from time t1 to time t4, but execute periodic communication processing from time t4 onwards. In other words, the control device 40 and the multiple monitoring devices 30 do not execute periodic communication processing immediately upon completion of connection processing, but rather wait to start periodic communication processing until all connection processing is complete.

[0092] When executing the periodic communication process, the control device 40 transmits request data to the monitoring devices 30, requesting the acquisition and transmission of battery monitoring information. The initial request data transmitted to each monitoring device 30 after the connection process may also serve as the transition instruction signal. Of course, a transition instruction signal separate from the request data may also be used.

[0093] Upon receiving the request data, the monitoring IC 33 of the monitoring device 30 acquires battery monitoring information and transmits it to the wireless IC 35. Then, the wireless IC 35 transmits data including the acquired battery monitoring information to the control device 40 as response data to the request data. The control device 40 receives the response data including the battery monitoring information. The control device 40 periodically transmits and receives battery monitoring information to each of the multiple monitoring devices 30. The control device 40 performs predetermined processing, such as estimating the internal resistance of the battery cell 22, based on the acquired battery monitoring information (step S16).

[0094] Although the example in which the monitoring device 30 acquires the battery monitoring information based on an acquisition request from the control device 40 has been described, the present invention is not limited to this. The monitoring device 30 may autonomously acquire the battery monitoring information and transmit the battery monitoring information it holds to the control device 40 based on a transmission request from the control device 40.

[0095] <Summary of the First Embodiment> Fig. 8 shows the flow of wireless communication at startup in a reference example. Fig. 9 shows the flow of wireless communication at startup in this embodiment. In Fig. 9, the monitoring device 30 is shown as an SBM, and the control device 40 is shown as an ECU. Also, as in Fig. 5, the battery management system 60 has n (n≧4) monitoring devices 30. The same is true in Fig. 8.

[0096] In the reference example shown in FIG. 8, there is no priority order in the wireless communication processing between the control device and multiple monitoring devices. Therefore, at startup, the monitoring device (SBM) that has completed connection processing with the control device (ECU) executes periodic communication processing first. Furthermore, the amount of data in the periodic communication processing is greater than the amount of data in the connection processing. As a result, the periodic communication processing occupies communication opportunities for the control device. As a result, the control device cannot receive advertisement packets, and the connection processing time with monitoring devices that have not completed connection processing becomes longer. The greater the number of monitoring devices, the longer the connection processing time for the monitoring device that completes connection processing last among the multiple monitoring devices. In particular, there is a significant delay in the timing of obtaining battery information from the last monitoring device (SBMn) that completes connection processing nth.

[0097] In this embodiment, the control device 40 performs connection processing with the monitoring device 30 with higher priority than periodic communication processing with any of the monitoring devices 30. In other words, the priority of the connection processing is higher than the priority of the periodic communication processing. The priority is sometimes referred to as priority or precedence. Therefore, the connection processing time can be shortened.

[0098] Note that the configuration is not limited to giving priority to connection processing with an arbitrary monitoring device 30 over periodic communication processing with all of the other monitoring devices 30 (remaining monitoring devices 30) excluding the arbitrary monitoring device 30. The control device 40 may execute connection processing with an arbitrary monitoring device 30 with priority over periodic communication processing with at least some of the other monitoring devices 30. The control device 40 may execute connection processing with an arbitrary monitoring device 30 with priority over periodic communication processing with some of the other monitoring devices 30. The control device 40 can execute connection processing with an arbitrary monitoring device 30 before executing periodic communication processing with some of the other monitoring devices 30.

[0099] 9, at startup, the control device 40 waits until connection processing with all monitoring devices 30 is complete before starting periodic communication processing with the monitoring devices 30 for which connection processing has been completed. The control device 40 does not start periodic communication processing with any monitoring device 30 for which connection processing has been completed before, until connection processing for the last monitoring device 30 (SBMn) for which connection processing has been completed is completed. Because the transition to periodic communication processing begins after all connection processing is complete, the connection processing time between the control device 40 and each monitoring device 30 at startup can be shortened. In other words, the time required for connection processing to be completed, or the so-called startup time, can be shortened.

[0100] Note that the configuration is not limited to waiting until connection processing with all monitoring devices 30 is complete at startup before starting periodic communication processing with a monitoring device 30 for which connection processing has been completed. The control device 40 may be configured to wait until connection processing with two or more monitoring devices 30 is complete at startup without starting periodic communication processing with a monitoring device 30 for which connection processing has been completed previously. This makes it possible to shorten the connection processing time between the control device 40 and each of the two or more monitoring devices 30.

[0101] Furthermore, in a configuration including many monitoring devices 30, it is possible to prevent significant delays in obtaining battery monitoring information from some of the monitoring devices 30. This allows for faster detection of abnormalities in the battery cells 22 or circuitry, for example. It is also possible to prevent adverse effects on the vehicle system including the battery pack 11, PCU 12, MG 13, and ECU 14.

[0102] In this embodiment, wireless communication processing between the control device 40 and the multiple monitoring devices 30 is performed according to a predetermined priority order. As illustrated in Figures 8 and 9, the time required for wireless communication processing can be reduced compared to wireless communication without a priority order.

[0103] (Second embodiment) This embodiment is a modification based on the preceding embodiment, and the description of the preceding embodiment can be used for this embodiment. In this embodiment, when reconnecting after a communication interruption, wireless communication processing is performed according to a predetermined priority order.

[0104] FIG. 10 is a timing chart showing an example of wireless communication when communication is interrupted. Like FIG. 5, FIG. 10 shows the communication status between the control device 40 and each of the n monitoring devices 30. FIG. 11 is a flowchart showing the processing executed by the control device 40 when reconnecting. FIG. 12 is a flowchart showing the processing executed by a monitoring device 30 that is a connection target and needs to be reconnected. FIG. 13 is a flowchart showing the processing executed by a monitoring device 30 that is not a connection target when another monitoring device reconnects. In the specification and drawings, the monitoring device 30 may be referred to as an SBM, and the control device 40 may be referred to as an ECU.

[0105] When a wireless communication interruption occurs during the periodic communication process, the control device 40 executes a connection process with the monitoring device 30 that has been interrupted. In other words, the control device 40 executes a reconnection. The communication interruption occurs, for example, due to a deterioration in the communication environment.

[0106] At time t11 shown in Fig. 10, a disruption occurs in wireless communication between the control device 40 and SBM2, which is one of the monitoring devices 30. As shown in Fig. 11, the control device 40 determines whether a disruption in communication has occurred (step S31). The control device 40 may repeatedly execute the process shown in Fig. 11 at a predetermined cycle. The control device 40 may also execute the process shown in Fig. 21 at the timing when a disruption in communication occurs.

[0107] If no disruption has occurred, the control device 40 ends the series of processes. On the other hand, if a disruption has occurred, the control device 40 stops periodic communication processing with all monitoring devices 30 except the monitoring device 30 where the disruption has occurred, that is, all monitoring devices 30 that are not to be connected (step S32). Next, the control device 40 starts connection processing with the monitoring device 30 where the disruption has occurred (step S33).

[0108] As shown in Fig. 12, the monitoring device 30 (SBM2) to be connected determines whether a communication interruption has occurred (step S41), and ends the series of processes if no interruption has occurred. If a communication interruption has occurred, the monitoring device 30 (SBM2) starts connection processing with the control device 40 (step S42). At time t12 shown in Fig. 10, the control device 40 and the monitoring device 30 to be connected start connection processing for reconnection.

[0109] As shown in Fig. 13, the monitoring device 30 that is not a target for connection stops the periodic communication process with the control device 40 in response to the process of step S32 executed by the control device 40 (step S51). The monitoring device 30 that is not a target for connection stops the periodic communication process, for example, when it stops receiving request data from the control device 40. The monitoring device 30 may stop the periodic communication process based on a stop signal sent by the control device 40 in conjunction with the stop of the periodic communication process. When the periodic communication process is stopped, communication between the control device 40 and the monitoring device 30 that is not a target for connection goes into a standby state, as shown in Fig. 10.

[0110] Next, the control device 40 determines whether or not the connection process with one of the monitoring devices 30 to be connected has been completed, as shown in FIG. 11 (step S34). If the connection process with one of the monitoring devices 30 has been completed, the control device 40 then determines whether or not the connection process with all of the monitoring devices to be connected has been completed (step S35). If there is only one monitoring device 30 to be connected, the processes of steps S34 and S35 can be combined into one common process. The monitoring device 30 to be connected determines whether or not the connection process with the control device 40 has been completed, as shown in FIG. 12 (step S43).

[0111] If any monitoring devices 30 to be connected remain, the control device 40 returns to step S33 and repeats the processes of steps S33, S34, and S35 until the connection process with all of the connection targets is completed. Similarly, the monitoring devices 30 to be connected repeat the processes of steps S42 and S43 until the connection process with the control device 40 is completed.

[0112] When the connection process with all connection targets is completed, the control device 40 then resumes the periodic communication process (step S36). As the periodic communication process is executed, the control device 40 transmits a signal to all monitoring devices 30 instructing them to transition to the periodic communication process.

[0113] When the connection processing with the control device 40 is completed in step S43, the monitoring device 30 to be connected next determines whether or not it is possible to transition to periodic communication processing (step S44). The monitoring device 30 to be connected determines that transition to periodic communication processing is not possible and repeats the processing of step S44 until it receives a transition instruction signal from the control device 40. When it receives a transition instruction signal from the control device 40, the monitoring device 30 determines that transition to periodic communication processing is possible and resumes periodic communication processing (step S45).

[0114] After stopping the periodic communication process, the non-connection monitoring device 30 determines whether or not it is possible to transition to periodic communication processing (step S52). The non-connection monitoring device 30 determines that transition to periodic communication processing is not possible and repeats the processing of step S52 until it receives a transition instruction signal from the control device 40. When it receives the transition instruction signal from the control device 40, the monitoring device 30 determines that transition to periodic communication processing is possible and resumes periodic communication processing (step S53).

[0115] As in the preceding embodiment, the initial request data that the control device 40 transmits to each of the monitoring devices 30 after the connection process may also serve as the transition instruction signal, or a transition instruction signal separate from the request data may be used.

[0116] 10, the control device 40 and the non-target monitoring device 30 do not execute periodic communication processing until time t13, when the connection processing of the target monitoring device 30 (SBM2) is completed. The non-target monitoring device 30 stops periodic communication processing when communication is interrupted, and resumes periodic communication processing after time t13 when reconnection is completed.

[0117] The reconnection process shown in Figures 11 to 13 is an interrupt process executed by the control device 40 and the multiple monitoring devices 30 during periodic communication processing. This process is executed, for example, during the processing of steps S15 and S25 shown in Figures 6 and 7. Of course, the reconnection process described above may be executed during periodic communication processing in a configuration in which the processing of steps S13, S14, S23, and S24 is excluded from Figures 6 and 7, that is, in a basic processing configuration. The other configurations are the same as those described in the preceding embodiment.

[0118] <Summary of the second embodiment> In this embodiment, as in the previous embodiment, wireless communication processing between the control device 40 and multiple monitoring devices 30 is performed according to a predetermined priority order. Therefore, the time required for wireless communication processing can be shortened compared to wireless communication without a priority order. Furthermore, the control device 40 performs connection processing with an arbitrary monitoring device 30 with priority over periodic communication processing with at least some of the other monitoring devices 30. In other words, the priority of connection processing with an arbitrary monitoring device 30 is higher than periodic communication processing with at least some of the other monitoring devices 30. Therefore, the connection processing time can be shortened. In particular, in this embodiment, the control device 40 performs connection processing with a monitoring device 30 with priority over periodic communication processing with any of the monitoring devices 30, so the connection processing time can be more reliably shortened.

[0119] In particular, in this embodiment, the control device 40 temporarily suspends periodic communication processing with any monitoring device 30 that requires reconnection until the connection processing with the other monitoring devices 30 is completed. Periodic communication processing resumes after reconnection is completed, shortening the connection processing time at the time of reconnection. This shortens the period during which battery monitoring information cannot be acquired. For example, even if an abnormality occurs in the cell voltage, circuit, or the like during reconnection, the short connection processing time allows the periodic communication processing to be resumed immediately, the abnormality to be detected, and measures to address the abnormality to be taken.

[0120] The number of monitoring devices 30 whose communication with the control device 40 has been interrupted is not limited to one. It may be multiple monitoring devices 30. In this case, the control device 40 temporarily suspends the periodic communication process with the other monitoring devices 30 until the connection process with all monitoring devices 30 whose communication has been interrupted is completed.

[0121] (Third embodiment) This embodiment is a modification of the preceding embodiment, and the description of the preceding embodiment can be used. In this embodiment, the connection process between the control device 40 and each of the multiple monitoring devices 30 is performed according to a predetermined priority.

[0122] FIG. 14 is a timing chart showing an example of wireless communication at startup. Like FIG. 5, FIG. 14 illustrates the communication status between the control device 40 and each of the n monitoring devices 30. FIG. 15 is a flowchart showing processing executed by the control device 40 at startup. For convenience, FIG. 15 omits periodic processing executed based on battery monitoring information. FIG. 16 is a flowchart showing processing executed by a monitoring device 30 that is the target of priority processing at startup. FIG. 17 is a flowchart showing processing executed by a non-target monitoring device 30. In the specification and drawings, the monitoring device 30 may be referred to as an SBM, and the control device 40 may be referred to as an ECU. Also, the target of priority processing may be simply referred to as a target. The target of priority processing has a higher priority for connection processing than the non-targets. As an example, of the n monitoring devices 30, the SBM 3 is the target of priority processing. The priority is, for example, determined in advance and stored in the memory of the control device 40 and the multiple monitoring devices 30.

[0123] At time t21 shown in Fig. 14, operating power is supplied to the control device 40 and each of the multiple monitoring devices 30. Upon receiving the operating power, the control device 40 starts up (step S61) as shown in Fig. 15, and starts connection processing with the target monitoring device 30 (SBM3) (step S62). Similarly, upon receiving the operating power, the target monitoring device 30 starts up (step S71) as shown in Fig. 16, and starts connection processing with the control device 40 (step S72). As a result, the communication state between the control device 40 and the monitoring device 30 (SBM3) that is the target of priority processing switches from non-connected to in connection processing at time t21, as shown in Fig. 14.

[0124] 17, after starting up (step S81), the non-target monitoring device 30 determines whether the connection process of the target monitoring device 30 has been completed (step S82). The non-target monitoring device 30 then repeats the process of step S82 until the connection process of the target monitoring device 30 is completed. In other words, the non-target monitoring device 30 does not immediately execute the connection process after starting up.

[0125] Next, the control device 40 determines whether the connection process with the target monitoring device 30 has been completed (step S63), as shown in FIG. 15. If not completed, the process returns to step S62, and the processes of steps S62 and S63 are repeated until completion. If completed, the control device 40 starts periodic communication processing with the target monitoring device 30 (step S64). Similarly, the target monitoring device 30 determines whether the connection process with the control device 40 has been completed (step S73), as shown in FIG. 15. If not completed, the process returns to step S72, and the processes of steps S72 and S73 are repeated until completion. If completed, the target monitoring device 30 starts periodic communication processing with the control device 40 (step S74). As a result, the communication state between the control device 40 and the monitoring device 30 (SBM3) that is the target of priority processing switches from connection processing to periodic communication processing at time t22, as shown in FIG. 14. The control device 40 acquires battery monitoring information from the monitoring device 30 for which connection processing has been completed, and starts predetermined processing related to that monitoring device 30.

[0126] Next, the control device 40 notifies the non-target monitoring devices 30 of the completion of the connection process with the target device (step S65), as shown in FIG. 15. Then, the control device 40 starts the connection process with the non-target monitoring devices 30 (step S66). Next, the control device 40 determines whether the connection process with all of the non-target monitoring devices 30 has been completed (step S67). The control device 40 repeats the processes of steps S66 and S67 until the connection process with all of the non-target monitoring devices 30 has been completed. When the connection process with all of the non-target monitoring devices 30 has been completed, the control device 40 starts periodic communication processing with the non-target monitoring devices (step S68). When starting the periodic communication processing, the control device 40 sends a signal to each of the non-target monitoring devices 30 instructing them to transition to periodic communication processing.

[0127] When the non-target monitoring devices 30 receive the completion notification from the control device 40, they determine in step S82 that the connection process for the target monitoring device 30 has been completed. Next, as shown in Fig. 17, each of the non-target monitoring devices 30 starts connection processing with the control device 40 (step S83). As a result, the communication state between the control device 40 and the non-target monitoring devices 30 switches from standby to connection processing at time t22, as shown in Fig. 14.

[0128] The non-target monitoring device 30 then determines whether the connection process with the control device 40 has been completed (step S84). If not completed, the process returns to step S83 and repeats steps S83 and S84 until completed. If completed, the non-target monitoring device 30 determines whether or not to transition to periodic communication processing (step S85). The non-target monitoring device 30 determines that transition to periodic communication processing is not possible until it receives a transition instruction signal from the control device 40, and repeats the process of step S85. Upon receiving the transition instruction signal from the control device 40, the non-target monitoring device 30 determines that transition to periodic communication processing is possible, and starts periodic communication processing (step S86). As a result, the control device 40 executes a predetermined process using the battery monitoring information obtained from the non-target monitoring device 30. The other configurations are the same as those described in the preceding embodiment.

[0129] <Summary of the third embodiment> In this embodiment, similar to the preceding embodiment, wireless communication processing between the control device 40 and the multiple monitoring devices 30 is performed according to a predetermined priority order. Therefore, the time required for wireless communication processing can be reduced compared to wireless communication without a priority order.

[0130] In particular, in this embodiment, the control device 40 executes connection processing with each of the multiple control devices 30 according to the priority of the connection processing with the multiple monitoring devices 30. The control device 40 does not execute connection processing with a monitoring device 30 with a lower priority until it has completed connection processing with a monitoring device 30 (SBM3) with a higher priority. This makes it possible to suppress radio wave interference during connection processing. Therefore, it is possible to shorten the connection processing time with a monitoring device 30 with a higher priority. By shortening the connection processing time, the control device 40 can obtain battery monitoring information from a monitoring device 30 with a higher priority before other monitoring devices 30.

[0131] In this embodiment, an example in which the priority is set in two stages has been shown, but this is not limiting. Three or more stages may also be set. An example in which there is one monitoring device 30 with a high priority has been shown, but this is not limiting. There may also be multiple monitoring devices 30 with a high priority. For example, there may be two monitoring devices 30 with a high priority, and the two may be further ranked.

[0132] The monitoring device 30 that receives priority in connection processing is not particularly limited. For example, in an assembled battery 20 configured by connecting a plurality of battery stacks 21 in series, the monitoring device 30 that monitors the battery cell 22 with the highest potential and / or the battery cell 22 with the lowest potential may be the target of priority processing. When the monitoring devices 30 monitor different numbers of battery cells 22, the monitoring device 30 that monitors the most battery cells 22 may be the target of priority processing.

[0133] Of the multiple monitoring devices 30, some selected monitoring devices 30 may be targeted for priority processing. In this case, the control device 40 may execute predetermined processing, such as estimating internal resistance, based on the battery monitoring information of the selected monitoring devices 30. This can reduce the time required for estimating internal resistance, compared to a configuration in which predetermined processing is executed using the battery monitoring information of all monitoring devices 30.

[0134] <Modification> Although the example in which the priority is determined in advance has been described, the present invention is not limited to this. The control device 40 may set the priority of the connection process based on the state of the battery cells 22 and / or an external command.

[0135] During the periodic communication process, the control device 40 determines whether or not there are any battery cells 22 that are expected to become abnormal, that is, whether or not an abnormality is expected, as shown in Fig. 18 (step S91). The control device 40 determines whether or not there are any battery cells 22 that are expected to become abnormal, based on the battery monitoring information acquired from the monitoring device 30 during the periodic communication process, the SOH estimated using the battery monitoring information, and the like. If no abnormality is expected, the control device 40 ends the process.

[0136] If an abnormality is predicted, the control device 40 sets a priority order so that connection processing with the monitoring device 30 monitoring the battery cell 22 predicted to have an abnormality is prioritized (step S92). In step S92, the control device 92 transmits connection processing priority information to the monitoring device 30. As a result, at the next startup, connection processing with the monitoring device 30 monitoring the battery cell 22 predicted to have an abnormality is prioritized over connection processing with other monitoring devices 30. In other words, the control device 40 can quickly obtain battery monitoring information related to the battery cell 22 predicted to have an abnormality. This enables early detection of an abnormality and action to be taken before an abnormality occurs.

[0137] While the periodic communication process is being performed, the control device 40 determines whether or not a command has been received from an external device, as shown in FIG. 19 (step S101). If no command has been received from the outside, the control device 40 ends the process. The external device is, for example, a tool used in an inspection factory of a dealer. When performing a defect analysis, the external device sends a wired command to the control device 40 to prioritize connection processing with the monitoring device 30 that monitors the battery cell 22 that is to be inspected first.

[0138] When receiving an external command, the control device 40 sets a priority order for the connection process based on the command (step S102). In step S92, the control device 92 transmits priority order information for the connection process to the monitoring device 30. As a result, at the next startup, the connection process with the monitoring device 30 is executed in accordance with the priority order according to the command from the external device. Therefore, the external device can quickly obtain battery monitoring information related to the battery cells 22 that is necessary for performing a malfunction analysis. This allows the analysis to be performed quickly. During such a malfunction analysis, the battery management system 60 may remain mounted on the vehicle 10 or may be detached from the vehicle 10.

[0139] While Fig. 19 shows an example in which the control device 40 receives commands from an external device and sets the priority, an alternative configuration is possible in which the external device performs the functions of the control device 40 during inspection and also sets the priority of the connection process. In this case, as shown in Fig. 20, the external device 80 communicates wirelessly with each of the multiple monitoring devices 30. The external device executes connection processing with each of the multiple monitoring devices 30, and executes periodic communication processing after the connection processing. The external device then sets the priority of the connection processing so as to prioritize connection processing with the monitoring device 30 that monitors the battery cell 22 that is to be inspected with priority.

[0140] When the external device 80 is configured to perform the functions of the control device 40, the battery management system 60 may be mounted on the vehicle 10 or may be detached from the vehicle 10. When detached from the vehicle, the battery management system 60 is required to include at least the battery cells 22 (battery pack 20), the monitoring device 30, and the sensor 70. In other words, the battery management system 60 is required to be configured to be able to transmit battery monitoring information to the external device 80 via wireless communication. Therefore, the battery management system 60 may be configured without the housing 50, and may be configured without the control device 40. Of course, the battery management system 60 may have the same configuration as when mounted on the vehicle. When the control device 40 is not included, the external device 80 may obtain the cell current from a current sensor.

[0141] In the present embodiment, an example has been shown in which connection processing is performed according to a predetermined priority order in a configuration in which wireless communication is performed between the control device 40 and each of the multiple monitoring devices 30. However, the configuration in which connection processing is performed according to a predetermined priority order is not limited to the above example. For example, in the example shown in Fig. 21, the battery management system 60 includes, as the multiple monitoring devices 30, a monitoring device 30m that wirelessly communicates with the control device 40 and multiple monitoring devices 30s that wirelessly communicate with the monitoring device 30m.

[0142] The monitoring device 30m communicates wirelessly with each of the multiple monitoring devices 30s to acquire battery monitoring information. When the monitoring device 30m acquires request data from the control device 40, it requests each of the monitoring devices 30s to acquire and transmit battery monitoring information. The monitoring device 30s acquires the battery monitoring information in response to the request and transmits it to the monitoring device 30m. In other words, the monitoring device 30m functions as a master, and the monitoring device 30s functions as a slave. The monitoring device 30m transmits the battery monitoring information it acquired in response to the request data and the battery monitoring information acquired from the other monitoring devices 30s via wireless communication to the control device 40 as response data. In this way, the monitoring device 30m aggregates the battery monitoring information of the multiple monitoring devices 30 and transmits it to the control device 40.

[0143] In the above configuration, the monitoring device 30m may prioritize connection processing with the control device 40 over connection processing with the monitoring device 30s. This allows the connection processing between the control device 40 and the monitoring device 30m, and ultimately the periodic communication processing, to be performed quickly. Furthermore, the monitoring device 30m may prioritize connection processing with some of the multiple monitoring devices 30s over connection processing with other parts.

[0144] (Fourth embodiment) This embodiment is a modification of the preceding embodiment as a base form, and the description of the preceding embodiment can be used. In this embodiment, periodic communication processing is executed in accordance with a predetermined priority order.

[0145] Fig. 22 is a timing chart showing an example of wireless communication when an abnormal state is expected. Like Fig. 5, Fig. 22 shows the communication state between the control device 40 and each of the n monitoring devices 30. Fig. 23 is a flowchart showing the processing executed by the control device 40. Fig. 24 is a flowchart showing the processing executed by the monitoring device 30 that is the target of priority processing. Fig. 25 is a flowchart showing the processing executed by the monitoring device 30 that is not the target of priority processing. In the specification and drawings, the monitoring device 30 may be referred to as an SBM, and the control device 40 may be referred to as an ECU.

[0146] During the periodic communication process, the control device 40 determines whether or not there is a battery cell 22 that is expected to become abnormal, that is, whether or not an abnormality is expected (step S111), as shown in Fig. 23. The control device 40 may execute the process shown in Fig. 23, for example, when battery information is acquired. The control device 40 may execute the process shown in Fig. 23 when an abnormal state is expected. The control device 40 determines whether or not there is a battery cell 22 that is expected to become abnormal, based on the battery monitoring information acquired from the monitoring device 30 during the periodic communication process, the SOH estimated using the battery monitoring information, and the like.

[0147] If no abnormality is predicted, the control device 40 ends the process. If an abnormality is predicted, the control device 40 temporarily stops periodic communication with monitoring devices 30 other than the monitoring device 30 monitoring the battery cell 22 predicted to have an abnormality, i.e., non-target monitoring devices 30 (step S112). The control device 40 maintains periodic communication with the priority target monitoring device 30 and stops periodic communication with the non-target monitoring devices 30.

[0148] 22 is the timing when the control device 40 detects a battery cell 22 that is predicted to become abnormal, that is, a battery cell 22 that is likely to become abnormal in the near future. As an example, an abnormality is predicted in a battery cell 22 monitored by the SBM2, which is one of the monitoring devices 30.

[0149] The monitoring device 30 (SBM2) that is the target of priority processing maintains regular communication processing with the control device 40 (step S121), as shown in Figure 24. The target monitoring device 30 periodically acquires battery monitoring information and transmits it to the control device 40.

[0150] As shown in FIG. 25, the non-target monitoring device 30 determines whether or not there is a stop request from the control device 40 (step S131). The monitoring device 30 may determine that there is a stop request if the control device 40 stops sending request data and does not receive the request data even after a predetermined time has elapsed. In a configuration in which the control device 40 transmits a stop request signal in the processing of step S112, the monitoring device 30 may determine that there is a stop request if this stop request signal is received. The non-target monitoring device 30 may repeatedly execute the processing shown in FIG. 25 at a predetermined cycle, for example. The monitoring device 30 may execute the processing shown in FIG. 25 at a timing when it is expected that an abnormal state will occur in which a stop state request has been received.

[0151] If there is no stop request, the non-target monitoring device 30 ends the series of processes. On the other hand, if there is a stop request, the monitoring device 30 temporarily stops the periodic communication process with the control device 40 (step S132). As a result, as shown in FIG. 22, the communication state between the control device 40 and the monitoring devices 30 other than SBM2 becomes standby from time t31. As described above, the periodic communication process between the priority target monitoring device 30 (SBM2) and the control device 40 is maintained even after time t31.

[0152] After executing step S112, the control device 40 determines whether the predetermined processing has been completed as shown in FIG. 23 (step S113). The predetermined processing is processing to avoid the abnormality predicted in step S111. The predetermined processing is, for example, equalization processing. The predetermined processing is, for example, charging or discharging. The control device 40 repeats the processing of step S113 until the predetermined processing is completed. When the predetermined processing is completed, the control device 40 resumes periodic communication processing with the non-target monitoring device 30 (step S114). Upon resuming periodic communication processing, the control device 40 transmits a signal to the non-target monitoring device 30 instructing it to transition to periodic communication processing.

[0153] After executing step S132, the non-target monitoring device 30 determines whether or not it is possible to transition to periodic communication processing, as shown in Fig. 25 (step S133). The non-target monitoring device 30 determines that it is not possible to transition to periodic communication processing and repeats the processing of step S133 until it receives a transition instruction signal from the control device 40. When it receives a transition instruction signal from the control device 40, the non-target monitoring device 30 determines that it is possible to transition to periodic communication processing and resumes periodic communication processing (step S134).

[0154] When the periodic communication process with the non-target monitoring device 30 is resumed, the initial request data sent by the control device 40 to each monitoring device 30 may also serve as a transition instruction signal, or a transition instruction signal separate from the request data may be used.

[0155] 22, predetermined processing for the anticipated abnormality is completed at time t32. The control device 40 and each of the non-target monitoring devices 30 suspend periodic communication processing from time t31 to time t32, and resume periodic communication processing after time t32.

[0156] The process when an abnormality is anticipated shown in Figures 23 to 25 is an interrupt process executed by the control device 40 and the multiple monitoring devices 30 during the periodic communication process. This process is executed, for example, during the processing of steps S15 and S25 shown in Figures 6 and 7. In a basic processing configuration that excludes the processing of steps S13, S14, S23, and S24 from Figures 6 and 7, the process when an abnormality is anticipated described above may be executed during the periodic communication process. The other configurations are the same as those described in the preceding embodiment.

[0157] <Summary of the Fourth Embodiment> In this embodiment, similar to the preceding embodiment, wireless communication processing between the control device 40 and the multiple monitoring devices 30 is performed according to a predetermined priority order. Therefore, the time required for wireless communication processing can be reduced compared to wireless communication without a priority order.

[0158] In particular, in this embodiment, the control device 40 executes periodic communication processing with each of the multiple monitoring devices 30 according to the priority order of the periodic communication processing. The control device 40 executes periodic communication processing with a specific monitoring device 30 with priority over periodic communication processing with other monitoring devices 30. This enables the timing of obtaining battery monitoring information from a specific monitoring device 30 to be accelerated.

[0159] For example, periodic communication processing with a monitoring device 30 that monitors a battery cell 22 where an abnormality is suspected is prioritized over periodic communication processing with other monitoring devices 30. In this case, the control device 40 can quickly obtain battery monitoring information about the battery cell 22 where an abnormality is suspected. This enables early detection of an abnormality and prompt action to be taken before an abnormality occurs.

[0160] Furthermore, periodic communication processes with higher priority are prioritized over periodic communication processes with lower priority, which prevents a periodic communication process with higher priority from being executed immediately after a periodic communication process with lower priority from being executed due to a large amount of data, thereby preventing a long time until the next periodic communication process can be executed.

[0161] (Fifth embodiment) This embodiment is a modification of the preceding embodiment as a basic configuration, and the description of the preceding embodiment can be used. In this embodiment, a configuration suitable for inspecting whether or not the battery pack 20 can be reused will be described.

[0162] <Inspection system> The assembled battery 20 (battery cells 22) included in the battery pack 11 is inspected (diagnosed) by inspection equipment 90 while removed from the vehicle 10, and a determination is made as to whether it can be reused. As shown in Fig. 26 , the inspection equipment 90 constructs an inspection system 100 together with the assembled battery 20 and a battery management system 60 that has been removed from the vehicle 10, and inspects the assembled battery 20. The inspection system 100 includes at least one battery management system 60 that has been removed from the vehicle 10, and the inspection equipment 90.

[0163] The inspection of the battery cells 22 by the inspection equipment 90 may be performed on a battery management system 60 basis, but it is more efficient to perform the inspection collectively for multiple battery management systems 60. In the example shown in Fig. 26, the inspection system 100 includes three battery management systems 60 (60A, 60B, 60C), and the inspection equipment 90 collectively inspects the battery cells 22 corresponding to the battery management systems 60A, 60B, 60C.

[0164] In the inspection system 100, the inspection equipment 90 wirelessly communicates with each of the monitoring devices 30 to acquire battery monitoring information for inspection. This battery monitoring information includes at least the battery information and fault diagnosis information described above.

[0165] The inspection equipment 90 inspects the deterioration state and / or abnormalities of the battery cells 22 and determines whether they can be reused based on the inspection results. The inspection equipment 90 determines whether the battery cells 22 (battery pack 20) ​​should be reused or recycled. The inspection equipment 90 may also be called an inspection tool, a diagnostic device, an external device, etc.

[0166] The battery management system 60, when removed from the vehicle 10 together with the battery pack 20, only needs to include at least the monitoring device 30 and the sensor 70. In other words, the battery management system 60 only needs to be configured to be able to transmit battery monitoring information to the inspection equipment 90 via wireless communication. Therefore, the battery management system 60 may be configured without the housing 50, and may also be configured without the control device 40. Of course, the system may have the same configuration as when mounted on the vehicle. If the control device 40 is not included, the inspection equipment 90 may acquire the cell current from a current sensor.

[0167] <Testing method> The inspection equipment 90 communicates wirelessly with the monitoring device 30 while the battery pack 20 is connected to a load (not shown), i.e., while the load is energized, to acquire battery monitoring information and inspect (diagnose) the deterioration state and abnormalities of the battery cells 22. Then, based on the inspection results, it determines whether the battery can be reused.

[0168] Similar to the control device 40, the inspection device 90 performs connection processing and periodic communication processing of battery monitoring information as wireless communication processing between each of the multiple monitoring devices 30. The inspection device 90 then performs wireless communication processing between the multiple monitoring devices 30 in accordance with a predetermined priority order.

[0169] The inspection device 90 can execute the same wireless communication process between the plurality of monitoring devices 30 as the wireless communication process executed between the control device 40 and the plurality of monitoring devices 30 in accordance with the priority order. An example of executing the same process as in the first embodiment will be described below.

[0170] Fig. 27 is a flowchart showing the processing executed by the inspection equipment 90 at startup. Fig. 28 is a flowchart showing the processing executed by each of the monitoring devices 30 at startup. Fig. 29 shows the flow of wireless communication between the inspection equipment 90 and multiple monitoring devices 30 at startup. In Fig. 29, the number of monitoring devices 30 that communicate wirelessly with the inspection equipment 90 is set to n. In the specification and drawings, the monitoring device 30 may be referred to as an SBM, and the control device 40 may be referred to as an ECU.

[0171] When supplied with operating power, the inspection equipment (IE) 90 starts up (step S211) as shown in Fig. 27 and starts connection processing with the monitoring device 30 (step S212). Similarly, when supplied with operating power, each of the multiple monitoring devices (SBM) 30 starts up (step S221) as shown in Fig. 28 and starts connection processing with the inspection equipment 90 (step S222).

[0172] Next, the control device 40 determines whether the connection process with one of the monitoring devices 30 has been completed (step S213). Similarly, the monitoring device 30 determines whether the connection process with the control device 40 has been completed (step S223). The inspection device 90 repeats steps S212 and S213 until the connection process with any of the monitoring devices 30 has been completed. The monitoring device 30 repeats the processes of steps S222 and S223 until the connection process with the inspection device 90 has been completed.

[0173] When the connection process between the inspection device 90 and one of the monitoring devices 30 is completed, the inspection device 90 transmits a completion notification to the corresponding monitoring device 30. Upon receiving the completion notification, the monitoring device 30 determines in step S223 that the connection process with the inspection device 90 is completed. This completes the connection process between the inspection device 90 and one of the monitoring devices 30.

[0174] If it is determined in step S213 that the connection process with one of the monitoring devices 30 has been completed, the testing device 90 then determines whether the connection process with all of the monitoring devices 30 with which it is communicating has been completed (step S214). If it is determined in step S214 that the connection process with all of the monitoring devices 30 has not been completed, the process returns to step S212 and continues the connection process with the incomplete monitoring devices 30. Once the connection process with all of the monitoring devices 30 has been completed, the testing device 90 then executes periodic communication processing (step S215). As the periodic communication processing is executed, the testing device 90 transmits a signal to all of the monitoring devices 30 instructing them to transition to periodic communication processing.

[0175] When the monitoring device 30 determines in step S223 that the connection process with the testing device 90 is complete, it then determines whether or not to transition to periodic communication processing (step S224). The monitoring device 30 determines that transition to periodic communication processing is not possible and repeats the processing of step S224 until it receives a transition instruction signal from the testing device 90. When the monitoring device 30 receives a transition instruction signal from the testing device 90, it determines that transition to periodic communication processing is possible and executes periodic communication processing (step S225).

[0176] The testing device 90 executes a predetermined process based on the battery monitoring information received in the periodic communication process (step S216). The predetermined process may include a process executed based on the battery monitoring information received during a predetermined sampling period. The predetermined process may include a process executed each time the testing device 90 acquires battery monitoring information.

[0177] The inspection device 90 inspects the deterioration state of the battery cells 22 by estimating the internal resistance and SOH of the battery cells 22 based on, for example, the acquired cell voltage and cell current. The inspection device 90 inspects the battery cells 22 and the monitoring device 30 for abnormalities based on, for example, fault diagnosis information. When inspecting battery packs 20 corresponding to multiple battery management systems 60 collectively, the multiple battery packs 20 (battery stacks 21) are connected in series, for example.

[0178] <Summary of the Fifth Embodiment> In this embodiment, the testing device 90 performs connection processing with the monitoring device 30 with higher priority than periodic communication processing with any of the monitoring devices 30. In other words, the priority of the connection processing is higher than the priority of the periodic communication processing. Therefore, the connection processing time can be shortened.

[0179] 29 in particular, at startup, the testing device 90 waits until connection processing with all monitoring devices 30 is complete before starting periodic communication processing with the monitoring devices 30 for which connection processing has been completed. The testing device 90 does not start periodic communication processing with any monitoring device 30 for which connection processing has been completed before, until connection processing for the last monitoring device 30 (SBMn) for which connection processing has been completed is completed. Because the transition to periodic communication processing begins after all connection processing is complete, the connection processing time between the testing device 90 and each monitoring device 30 at startup can be shortened. In other words, the time it takes to complete connection processing, or the so-called startup time, can be shortened.

[0180] Furthermore, when inspecting whether or not a battery can be reused, a large number of assembled batteries 20 are inspected at once. As a result, a large number of monitoring devices 30 communicate wirelessly with the inspection equipment 90. In such a configuration, by employing the inspection method described above, it is possible to prevent significant delays in obtaining battery monitoring information from some of the monitoring devices 30, particularly from monitoring devices 30 that are connected at the end of the process. This makes it possible to speed up the detection of abnormalities in the battery cells 22 or circuitry, for example.

[0181] In the configurations shown in the respective embodiments, the inspection device 90 can execute the same processing as that executed by the control device 40. In other words, the processing executed by the inspection device 90 between the plurality of monitoring devices 30 is not limited to the examples shown in FIGS. 27 to 29. In any of the configurations, the inspection device 90 executes wireless communication processing between the plurality of monitoring devices 30 according to a predetermined priority order. Therefore, the time required for wireless communication processing can be shortened compared to wireless communication without a priority order.

[0182] The inspection device 90 may acquire manufacturing history information from the monitoring device 30 through periodic communication processing. The manufacturing history information may be, for example, a manufacturing ID (serial number), manufacturing date and time, etc. In this case, the inspection device 90 may inspect (determine) the deterioration state based on the manufacturing history information. The inspection device 90 inspects (determines) the deterioration state of the battery cells 22 based on, for example, the acquired manufacturing history information. The inspection device 90 inspects the deterioration state of the battery cells 22 based on, for example, the elapsed time since the manufacturing date. The inspection device 90 may acquire battery monitoring information and / or manufacturing history information to inspect the deterioration state or abnormality of the battery cells 22.

[0183] The situation in which the battery pack 20 is inspected by the inspection device 90 while the battery pack 20 and the battery management system 60 are removed from the mobile object is not limited to an inspection of whether the battery pack 20 can be reused. For example, the inspection may be an inspection during the manufacture of the battery pack 11 or an inspection at a repair shop. During these inspections, the inspection device 90 may execute wireless communication processing with the multiple monitoring devices 30 according to a predetermined priority order.

[0184] (Other embodiments) The disclosure in this specification and drawings, etc. is not limited to the exemplified embodiments. The disclosure encompasses the exemplified embodiments and modifications thereto by those skilled in the art. For example, the disclosure is not limited to the combinations of parts and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure encompasses the omission of parts and / or elements from the embodiments. The disclosure encompasses the substitution or combination of parts and / or elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. Some disclosed technical scopes are defined by the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the claims.

[0185] The disclosure in the specification, drawings, etc. is not limited by the claims. The disclosure in the specification, drawings, etc. encompasses the technical ideas described in the claims, and extends to more diverse and broader technical ideas than the technical ideas described in the claims. Therefore, various technical ideas can be extracted from the disclosure in the specification, drawings, etc. without being bound by the claims.

[0186] When an element or layer is referred to as being "on," "coupled," "connected," or "coupled," it may be directly on, coupled, connected, or coupled to another element or layer, and intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly coupled," "directly connected," or "directly coupled" to another element or layer, there are no intervening elements or layers present. Other language used to describe relationships between elements should be construed in a similar manner (e.g., "between" vs. "directly between," "adjacent" vs. "directly adjacent," etc.). As used in this specification, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0187] Spatially relative terms such as "inside," "outside," "back," "below," "low," "top," "top," and the like are used herein to facilitate the description of one element or feature's relationship to other elements or features, as illustrated. Spatially relative terms may be intended to encompass different orientations of the device during use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures were turned over, elements described as "below" or "directly below" other elements or features would then be oriented "above" the other elements or features. Thus, the term "bottom" can encompass both an orientation of top and bottom. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used in this specification would be interpreted accordingly.

[0188] The apparatus, system, and methods described herein may be implemented by a special-purpose computer comprising a processor programmed to perform one or more functions embodied in a computer program. Alternatively, the apparatus and methods described herein may be implemented by special-purpose hardware logic circuitry. Alternatively, the apparatus and methods described herein may be implemented by one or more special-purpose computers comprising a processor executing a computer program in combination with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory storage medium.

[0189] For example, although an example in which the monitoring device 30 includes a microcomputer 34 has been described, the present invention is not limited to this. As shown in Fig. 30, a battery management system 60 may be employed in which the monitoring device 30 does not include a microcomputer 34. Fig. 30 corresponds to Fig. 4. In this configuration, the wireless IC 35 transmits and receives data to and from the monitoring IC 33. The scheduling control of sensing and self-diagnosis by the monitoring IC 33 may be performed by the wireless IC 35 or by the main microcomputer 45 of the control device 40.

[0190] Although an example in which a monitoring device 30 is provided for each battery stack 21 has been shown, this is not limiting. For example, one monitoring device 30 may be provided for multiple battery stacks 21. Multiple monitoring devices 30 may be provided for one battery stack 21.

[0191] Although the example in which the battery pack 11 includes one control device 40 has been described, this is not limiting. The battery pack 11 may include multiple control devices 40. Although the example in which the control device 40 includes one wireless IC 44 has been described, this is not limiting. The battery pack 11 may include multiple wireless ICs 44. Each of the multiple wireless ICs 44 may wirelessly communicate with multiple monitoring devices 30 that are different from each other.

[0192] Although the monitoring device 30 has been described as including one monitoring IC 33, the present invention is not limited to this. A plurality of monitoring ICs 33 may be included. In this case, a wireless IC 35 may be provided for each monitoring IC 33, or one wireless IC 35 may be provided for the plurality of monitoring ICs 33.

[0193] Although the example in which the control device 40 is disposed inside the housing 50 has been shown, the present invention is not limited to this. The control device 40 may also be disposed outside the housing 50.

[0194] The arrangement and number of the battery stacks 21 and battery cells 22 that make up the battery pack 20 are not limited to the above example. In the battery pack 11, the arrangement of the monitoring device 30 and / or the control device 40 is not limited to the above example. [Explanation of symbols]

[0195] 10...vehicle, 11...battery pack, 12...PCU, 13...MG, 14...ECU, 15...battery, 20...battery pack, 21...battery stack, 22...battery cell, 23...busbar unit, 24...busbar, 25...positive terminal, 26...negative terminal, 27...busbar cover, 30...monitoring device, 31, 311, 312, 313...power supply circuit, 32...multiplexer, 33...monitoring IC, 34...microcontroller, 35...wireless IC, 36...front-end circuit, 37...antenna, 40...control device, 41, 411, 412...power supply circuit, 42...antenna, 43...front-end circuit, 44...wireless IC, 45...main microcontroller, 46...sub-microcontroller, 50...casing, 60...battery management system, 70...sensor, 80...external device, 90...inspection equipment, 100...inspection system

Claims

1. a plurality of monitoring devices (30) disposed in a housing (50) that houses batteries (20, 21, 22), and configured to acquire and monitor battery monitoring information including information indicating the state of the batteries; a control device (40) that wirelessly communicates with the plurality of monitoring devices and executes predetermined processing based on the battery monitoring information; the control device and each of the plurality of monitoring devices execute, as a wireless communication process, a wireless communication connection process, and, after completion of the connection process, a periodic communication process in which the monitoring device periodically transmits the battery monitoring information to the control device; The control device executes the wireless communication process among the plurality of monitoring devices in accordance with a predetermined priority order.

2. The battery management system according to claim 1, A battery management system in which the control device prioritizes the connection process with any one of the monitoring devices over the periodic communication process with at least some of the other monitoring devices excluding the any one of the monitoring devices.

3. 3. The battery management system according to claim 2, A battery management system in which, when the control device and the multiple monitoring devices are started, the control device waits to start the periodic communication process with the monitoring device for which the connection process has been completed until the connection process with two or more of the monitoring devices is completed.

4. 4. The battery management system according to claim 2, wherein: A battery management system in which, when communication between the control device and any of the monitoring devices is interrupted, the control device stops the periodic communication process with other monitoring devices except for the any of the monitoring devices until the connection process with the any of the monitoring devices is completed.

5. The battery management system according to claim 1, The control device executes the connection process with each of the plurality of monitoring devices in accordance with a priority order of the connection process with the plurality of monitoring devices.

6. 6. The battery management system according to claim 5, The control device sets a priority order for the connection process based on a state of the battery and / or an external command.

7. 6. The battery management system according to claim 5, which is mounted on a mobile body, The external device (80) and each of the plurality of monitoring devices execute, as a wireless communication process, a wireless communication connection process, and, after the connection process is completed, a periodic communication process in which the monitoring device periodically transmits the battery monitoring information to the external device; The battery management system, wherein the external device prioritizes the connection process with a specific monitoring device over the connection processes with other monitoring devices other than the specific monitoring device.

8. The battery management system according to any one of claims 1 to 7, The control device executes the periodic communication process with each of the plurality of monitoring devices in accordance with a priority order of the periodic communication process.

9. The battery management system according to claim 8, A battery management system in which, when it is expected that the battery will enter an abnormal state, the control device prioritizes the periodic communication processing with the monitoring device corresponding to the battery that will enter the abnormal state over the periodic communication processing with other monitoring devices.

10. The battery management system according to any one of claims 1 to 9, which is mounted on a moving body, In a state where the battery is removed from the mobile object, The inspection device (90) and each of the plurality of monitoring devices execute, as a wireless communication process, a wireless communication connection process, and, after the connection process is completed, a periodic communication process in which the monitoring device periodically transmits the battery monitoring information and / or manufacturing history information to the inspection device; The battery management system is configured so that the inspection equipment executes the wireless communication processing among the plurality of monitoring devices in accordance with a predetermined priority order.

11. A method for managing batteries (20, 21, 22) by wirelessly communicating between a plurality of monitoring devices (30) that are arranged in a housing (50) that houses the batteries and that acquire and monitor battery monitoring information including information indicating the states of the batteries, and a control device (40) that executes predetermined processing based on the battery monitoring information, comprising: The control device and each of the plurality of monitoring devices perform wireless communication processing as follows: Executes wireless communication connection processing, After the connection process is completed, the monitoring device executes a periodic communication process in which the monitoring device periodically transmits the battery monitoring information to the control device; The control device executes the wireless communication process among the plurality of monitoring devices in accordance with a predetermined priority order.

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