Battery Management System

Abstract

To advance the acquisition timing of battery monitoring information.SOLUTION: A battery management system includes one or more monitoring devices 30 and a control device 40. The monitoring devices 30 acquire and monitor battery monitoring information including information indicating the state of batteries. The control device 40 wirelessly communicates with the monitoring devices 30 and performs predetermined processing based on the battery monitoring information. The monitoring devices 30 include the battery monitoring information in packets and transmit them to the control device 40 during a period in which wireless communication connection processing is being performed with the control device 40.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The disclosure in this specification relates to battery management To the system .

Background Art

[0002] Patent Document 1 discloses a battery management system using wireless communication. The description of the prior art document is incorporated herein by reference as an explanation of the technical elements in this specification.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a battery management system using wireless communication, wireless communication is performed between a monitoring device that monitors the state of a battery and a control device. The control device acquires battery monitoring information from the monitoring device by wireless communication and executes predetermined processing. In the case of wireless communication, a connection process for wireless communication is required between the monitoring device and the control device. For this reason, the acquisition timing (acquisition start timing) of battery monitoring information is slower than that of wired communication. The delay in acquiring battery monitoring information causes, for example, a decrease in controllability and a delay in anomaly detection. From the above viewpoints or other viewpoints not mentioned, further improvements are required for the battery management system and the battery management method.

[0005] One object to be disclosed is to provide a battery management that can accelerate the acquisition timing of battery monitoring information The system .

Means for Solving the Problems

[0006] The battery management system disclosed herein is One or more monitoring devices (30) are arranged in a housing (50) that houses batteries (20, 21, 22), and acquire and monitor battery monitoring information including information indicating the state of the batteries. A control device (40) that performs wireless communication with the monitoring device and executes a predetermined process based on the battery monitoring information. The monitoring device Obtain a plurality of battery monitoring information including the cell voltage which is the voltage of the battery cells constituting the battery and the cell temperature which is the temperature of the battery cells During the period of executing the connection process of wireless communication with the control device, include the battery monitoring information in the packet and transmit it to the control device. During the period of the connection process executed when starting the monitoring device and the control device by supplying the start signal, preferentially transmit the cell voltage among the plurality of battery monitoring information .

[0007] According to the disclosed battery management system, the monitoring device includes the battery monitoring information in the packet during the connection process and transmits it. Thereby, the timing for the control device to acquire the battery monitoring information can be advanced.

[0010] In the plurality of aspects disclosed in this specification, different technical means are adopted to achieve their respective purposes. The scope of the claims and the reference numerals in parentheses described in this section exemplarily show the correspondence with the parts of the embodiments described later, and are not intended to limit the technical scope. The objects, features, and effects disclosed in this specification will become clearer by referring to the subsequent detailed description and the accompanying drawings.

Brief Description of the Drawings

[0011]

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Embodiments for Carrying Out the Invention

[0012] Hereinafter, a plurality of embodiments will be described with reference to the drawings. In each embodiment, the corresponding components may be denoted by the same reference numerals, and redundant descriptions may be omitted. When only a part of the configuration is described in each embodiment, the configuration of other embodiments described previously can be applied to other parts of the said configuration. Also, not only the combinations of configurations explicitly shown in the description of each embodiment, but also the configurations of a plurality of embodiments can be partially combined with each other without any problem in the combination, even if not explicitly shown.

[0013] (First Embodiment) First, based on FIG. 1, the configuration of a vehicle equipped with the battery management system according to this embodiment, particularly a vehicle related to a battery pack equipped with the battery management system, will be described. FIG. 1 is a diagram showing the schematic configuration of a vehicle. The vehicle is an electric vehicle such as a battery 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 mobile bodies other than vehicles, such as flying bodies like drones, ships, construction machinery, and agricultural machinery. The battery management system can also be applied to stationary batteries (storage batteries) for household or business use.

[0014] <Vehicle> As shown in FIG. 1, the 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. ECU is an abbreviation for Electronic Control Unit.

[0015] The battery pack 11 includes a battery module 20 described later and provides a DC voltage source that can be charged and discharged. The battery pack 11 supplies power to the 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 may be referred to as the main battery.

[0016] The battery pack 11 is arranged, for example, in the front compartment of the vehicle 10 as shown in FIG. 1. The battery pack 11 may be arranged in the rear compartment, under the seat, or under the floor. For example, in the case of a hybrid vehicle, the compartment where the engine is arranged may be referred to as the engine compartment, engine room, etc.

[0017] The battery pack 11 is temperature-adjusted by the running wind of the vehicle 10 and the cooling wind supplied from a fan mounted on the vehicle 10. The battery pack 11 may be temperature-adjusted by a cooling liquid circulating inside the vehicle 10. By the above-described temperature adjustment, excessive temperature changes of the battery pack 11 are suppressed. Note that the battery pack 11 may simply be connected in a thermally conductive manner to a member having a large heat capacity such as the body of the vehicle 10.

[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 may be referred to as a power converter. The PCU 12 can include an inverter and a converter. The converter is disposed in the energization path between the battery pack 11 and the inverter. The converter has a function of boosting and bucking a DC voltage. The inverter converts the DC voltage boosted 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 generated power of 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 in which permanent magnets are embedded in a rotor. The MG 13 functions as a running drive source of the vehicle 10, that is, an electric motor. The MG 13 is driven by the PCU 12 to generate a rotational driving force. The driving force generated by the MG 13 is transmitted to the drive wheels. The MG 13 functions as a generator during braking of the vehicle 10 and performs regenerative power generation. The generated power of the MG 13 is supplied to the battery pack 11 through the PCU 12 and stored in the battery modules 20 in the battery pack 11.

[0020] ECU14 is configured to include a computer that includes a processor, a memory, an input / output interface, and a bus that connects 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-transitory tangible storage medium that non-temporarily stores programs and data that can be read by a computer. The memory stores various programs executed by the processor.

[0021] ECU14, for example, acquires information about the battery pack 20 from the battery pack 11 and controls the driving of MG13 and the charging and discharging of the battery pack 11 by controlling the PCU12. ECU14 may acquire information such as the voltage, temperature, current, SOC, and SOH of the battery pack 20 from the battery pack 11. ECU14 may acquire battery information such as the voltage, temperature, and current of the battery pack 20 and 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 ECU14 executes, for example, a plurality of instructions included in the PCU control program stored in the memory. As a result, ECU14 constructs a plurality of functional units for controlling the PCU12. In this way, in ECU14, a program stored in the memory causes the processor to execute a plurality of instructions, thereby constructing a plurality of functional units. ECU14 may be referred to as an EVECU.

[0023] <Battery Pack> Next, based on FIGS. 2 and 3, an example of the configuration of the battery pack 11 will be described. FIG. 2 is a perspective view schematically showing the inside of the battery pack 11. In FIG. 2, the housing is shown by a two-dot chain line. FIG. 3 is a plan view showing the upper surface of each battery stack.

[0024] As shown in FIG. 2, the battery pack 11 includes a battery assembly 20, a plurality of monitoring devices 30, a control device 40, and a housing 50. Hereinafter, as shown in FIG. 2, among the respective surfaces of the housing 50 which is substantially a rectangular parallelepiped, in the mounting surface on the vehicle 10, the longitudinal direction is indicated as the X direction, and the short side direction is indicated as the Y direction. In FIG. 2, the lower surface is the mounting surface. Then, the vertical direction perpendicular to the mounting surface is indicated as the Z direction. The X direction, the Y direction, and the Z direction are in a mutually orthogonal positional relationship. In the present 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 vertical direction corresponds to the Z direction. The arrangements in FIGS. 2 and 3 are merely examples, and the battery pack 11 may be arranged in any manner with respect to the vehicle 10.

[0025] The battery assembly 20 has a plurality of battery stacks 21 arranged side by side in the X direction. The battery stack 21 may be referred to as a battery block, a battery module, etc. The battery assembly 20 is configured by connecting a plurality of battery stacks 21 in series and / or in parallel. In the present embodiment, a 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). Thereby, the relative positions of the plurality of battery cells 22 are fixed. The case is made of metal or resin. When the case is made of metal, an electrically insulating member may be partially or entirely interposed between the wall surface of the case and the battery cell 22.

[0027] Note that as long as the relative positions of the plurality of battery cells 22 can be fixed, the form of the fixing member is not particularly limited. For example, a configuration in which the plurality of battery cells 22 are constrained by a belt - shaped band can also be adopted. In this case, a separator for maintaining the separation distance between the plurality of battery cells 22 may be interposed therebetween.

[0028] The battery stack 21 has a plurality of battery cells 22 connected in series. The battery stack 21 of the present 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 above-described DC voltage source. The assembled battery 20, the battery stack 21, and the battery cell 22 correspond to a battery.

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

[0030] The battery cell 22 has a power generation element and a battery case that houses this power generation 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 surfaces, which are two end faces arranged in the Z direction and two each arranged in the X direction and two arranged in the Y direction. The battery case of the present embodiment is made of metal.

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

[0032] On the upper surface of each battery stack 21, linear bus bar units 23 are arranged at both ends in the X direction. The bus bar unit 23 is arranged at both ends in the X direction of the protruding end faces of the positive electrode terminals 25 and the negative electrode terminals 26 of a plurality of battery cases. That is, a pair of bus bar units 23 are arranged in each battery stack 21.

[0033] Each bus bar unit 23 has a plurality of bus bars 24 that electrically connect the positive electrode terminals 25 and the negative electrode terminals 26 that are alternately arranged in the Y direction, and a bus bar cover 27 that covers the plurality of bus bars 24. The bus bar 24 is a plate material made of a metal with good conductivity such as copper or aluminum. The bus bar 24 electrically connects the positive electrode terminal 25 and the negative electrode terminal 26 of the adjacent battery cells 22 in the Y direction. Thereby, in each battery stack 21, a plurality of battery cells 22 are connected in series.

[0034] With such a connection structure, in each battery stack 21, one of the two battery cells 22 located at the ends of the plurality of battery cells 22 arranged in the Y direction becomes the highest potential, and the other becomes the lowest potential. A predetermined wiring 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] As shown in FIG. 2, the plurality of battery stacks 21 are arranged side by side in the X direction. The positive electrode terminal 25 of the battery cell 22 with the highest potential in one of the two adjacent battery stacks 21 in the X direction and the negative electrode terminal 26 of the battery cell 22 with the lowest potential in the other are connected via a predetermined wiring. Thereby, the plurality of battery stacks 21 are connected in series.

[0036] With such a connection structure, one of the two battery stacks 21 located at the ends of the plurality of battery stacks 21 arranged 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 plurality of 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 plurality of battery cells 22. These two output terminals are connected to electrical devices mounted on the vehicle 10 such as the PCU 12.

[0037] Note that two adjacent battery stacks 21 in the X direction do not necessarily need to be electrically connected via a predetermined wiring. Any two of the plurality of battery stacks 21 arranged in the X direction may be electrically connected via a predetermined wiring. Also, the Y-direction positions of the positive electrode terminal 25 and the negative electrode terminal 26 that are electrically connected via a predetermined wiring may be the same or different. That is, these positive electrode terminal 25 and 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 part of the other may be located in the projection area of one of the positive electrode terminal 25 and the negative electrode terminal 26 in the X direction, or may not be located at all.

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

[0039] The monitoring device 30 is provided individually for the plurality of battery stacks 21. As shown in FIG. 2, the monitoring device 30 is disposed between a pair of bus bar 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 described above in the Z direction. The monitoring device 30 and this end face may be separated in the Z direction, or may be in contact facing each other in the Z direction. An intervening object such as an insulating sheet may be provided between the monitoring device 30 and this end face.

[0040] The monitoring device 30 is fixed to the bus bar unit 23 with screws or the like. As will be described later, the monitoring device 30 is configured to be capable of wireless communication with the control device 40. An antenna 37 (to be described later) provided in the monitoring device 30 is arranged so as not to overlap with the bus bar unit 23 in the Z direction, that is, to protrude more than the bus bar unit 23 in the Z direction.

[0041] In addition, as the material of the connecting member such as a screw for connecting the monitoring device 30 and the bus bar unit 23, for example, a non-magnetic material can be adopted in order to avoid interference with wireless communication. In addition to this screw, in the components provided in the battery stack 21, a non-magnetic material can be adopted as the constituent material of the components that do not particularly need to have magnetism.

[0042] In the present embodiment, a plurality of monitoring devices 30 are arranged side by side in the X direction. And the positions of the plurality of monitoring devices 30 in the Y direction are equal. Due to the configuration shown above, the extension of the separation distance between the plurality of monitoring devices 30 is suppressed.

[0043] The control device 40 is attached to the outer surface of the battery stack 21 arranged at one end in the X direction. The control device 40 is configured to be capable of wireless communication with each monitoring device 30. An antenna 42 (to be described later) provided in the control device 40 is arranged at approximately the same height as the antenna 37 of the monitoring device 30 in the Z direction. That is, the antenna 42 of the control device 40 is provided so as to protrude more than the bus bar 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 (to be described later). That is, the battery pack 11 is provided with the battery management system 60.

[0045] In order to prevent the battery pack 11 from becoming an electromagnetic noise source, it is necessary to suppress the leakage of radio waves of wireless communication to the outside of the space (communication space) where wireless communication between the monitoring device 30 and the control device 40 is performed. Conversely, in order to suppress the interference of this wireless communication, it is necessary to suppress the intrusion of electromagnetic noise into the communication space.

[0046] For this reason, the housing 50 has, for example, the performance of reflecting electromagnetic waves. The housing 50 is provided with the materials shown below as an example 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 its surface. The housing 50 is provided with a resin material and a magnetic material embedded therein. The housing 50 is provided with carbon fibers. Instead of the performance of reflecting electromagnetic waves, the housing 50 may have the performance of absorbing electromagnetic waves.

[0047] The housing 50 may have a hole that communicates between its inner accommodation space and the outer space (external space). The hole is partitioned by a connecting surface between the inner surface and the outer surface of the housing 50. This hole is used for ventilation, taking out power lines, taking out signal lines, etc. In the case of a configuration having a hole, a covering portion may be provided for the hole. The communication between the accommodation space and the external space is blocked by the covering portion. The covering portion may block all of the holes or may block a part of the holes.

[0048] The covering portion is provided, for example, on any one of the inner surface, the outer surface, and the connecting surface of the housing 50. The covering portion may be arranged opposite to the hole in a manner of covering the hole without being provided on any of these inner surface, outer surface, and connecting surface. When the covering portion and the hole are separated, the separation distance 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 orthogonal to this distance.

[0049] The covering portion is, for example, a connector, an electromagnetic shielding member, a sealing material, etc. The covering portion is provided with the materials shown below as an example. The covering portion is provided with a magnetic material such as metal, for example. The covering portion is provided with a resin material and a magnetic material covering its surface. The covering portion is provided with a resin material and a magnetic material embedded therein. The covering portion is provided with carbon fibers. The covering portion contains a resin material.

[0050] The holes in the housing 50 may be covered by at least one of the elements housed in the accommodation space of the housing 50. The separation distance between the accommodation and the holes is shorter than the length of the holes described above. Also, power lines and signal lines may be arranged across the accommodation space and the external space while being held by an electrical insulating member that forms part of the wall of the housing 50.

[0051] <Battery Management System> Next, based on FIG. 4, the schematic configuration of the battery management system will be described. 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 a plurality of monitoring devices (SBM) 30 and a control device (ECU) 40. Hereinafter, the monitoring device may be referred to as SBM. The control device 40 may be referred to as a battery ECU, BMU, etc. BMU is an abbreviation for Battery Management Unit. The battery management system 60 is a system that manages the battery using wireless communication. In this wireless communication, a frequency band used for short-range communication, for example, the 2.4 GHz band or the 5 GHz band, is used.

[0053] The battery management system 60 adopts one-to-one communication or network communication according to the number of nodes of wireless communication by the monitoring device 30 and / or the control device 40. The number of nodes can change depending on the standby state of the monitoring device 30 and / or the control device 40. When the number of nodes is two, the battery management system 60 adopts one-to-one communication. When the number of nodes is three or more, the battery management system 60 adopts network communication. One form of network communication is star communication in which wireless communication is performed between all of a master and slaves, with one node as the master and the remaining nodes as slaves. Another form of network communication is chain communication in which a plurality of 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 that detects the physical quantity of each battery cell 22, a discrimination sensor, and the like. 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 a 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 discriminates whether the correct battery is attached or not.

[0056] The temperature sensor is selectively provided in a part of the plurality of battery cells 22 included in the battery stack 21. The temperature sensor detects the temperature (cell temperature) of the selected battery cell 22 as the temperature of the battery stack 21. The temperature sensor is provided in the battery cell 22 that is assumed to have the highest temperature, the battery cell 22 that is assumed to have the lowest temperature, the battery cell 22 that is assumed to have an intermediate temperature, etc. among the plurality of battery cells 22 included in one battery stack 21. The number of temperature sensors for one battery stack 21 is not particularly limited.

[0057] The current sensor is provided in a plurality of battery stacks 21. The current sensor detects the current (cell current) that commonly flows through each of the plurality of battery cells 22 connected in series and each of the plurality of battery stacks 21 connected in series. In the present embodiment, since all the battery stacks 21 are connected in series, 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 configurations of the respective monitoring devices 30 are common to each other. 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). Communication between the respective elements in the monitoring device 30 is performed by wire.

[0059] The power supply circuit 31 generates the operating power supply for other circuit elements included in the monitoring device 30 using the voltage supplied from the battery stack 21. In the present 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 the detection signals of at least a part of the plurality of sensors 70 provided in the battery pack 11 and outputs the selected signal. The multiplexer 32 selects (switches) the input according to the 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 directly acquires the cell voltage from the voltage sensor and acquires information such as the cell temperature through the multiplexer 32. The monitoring IC 33 acquires the cell voltage in association with which battery cell 22 the value belongs to. That is, the cell voltage is acquired while discriminating the cell. 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 by wire.

[0062] The monitoring IC 33 is sometimes referred to as a cell supervising circuit (CSC). CSC is an abbreviation of Cell Supervising Circuit. The monitoring IC 33 performs a failure diagnosis of the circuit portion of the monitoring device 30 including itself. That is, the monitoring IC 33 transmits battery monitoring information including battery information and failure diagnosis information to the microcomputer 34. The monitoring device 30 may store (save) the acquired battery monitoring information in a memory such as the microcomputer 34. When the monitoring IC 33 receives data requesting acquisition of the battery monitoring information transmitted 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 above-described example, the battery monitoring information may include information such as the exhaust gas temperature, impedance, state of equalization of cell voltages, stack voltage, state of synchronization with the control device 40, and presence or absence of abnormality in the detection wiring.

[0063] The microcomputer 34 is a microcomputer including a CPU which is a processor, a ROM and a RAM which are memories, an input / output interface, and a bus connecting these. The CPU constructs a plurality of functional units by executing various programs stored in the ROM while using the temporary storage function of the RAM. ROM is an abbreviation of Read Only Memory. RAM is an abbreviation of Random Access Memory.

[0064] The microcomputer 34 controls the schedule of sensing and self-diagnosis by the monitoring IC 33. The microcomputer 34 receives the 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, it 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 (not shown) and a microcomputer for wirelessly transmitting and receiving data. The microcomputer includes a memory. The wireless IC 35 has a transmission function of modulating transmission data and oscillating at the frequency of the RF signal. The wireless IC 35 has a reception function of demodulating reception 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 then 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 the wireless communication between other nodes.

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

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

[0069] Antenna 37 converts an electrical signal into a radio wave and radiates it into space. Antenna 37 receives a radio wave propagating in space and converts it into an electrical 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 each element within the control device 40 is performed by wire.

[0071] The power supply circuit 41 generates an operating power supply for other circuit elements included in the control device 40 using the voltage supplied from the battery (BAT) 15. The battery 15 is a DC voltage source separate from the battery pack 11 mounted on the vehicle 10. The battery 15 may be referred to as an auxiliary battery because it supplies power to the accessories of the vehicle 10. In the present 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. For simplicity of the figure, 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] Antenna 42 converts an electrical signal into a radio wave and radiates it into space. Antenna 42 receives a radio wave propagating in space and converts it into an electrical signal.

[0073] The front-end circuit 43 has a matching circuit for impedance matching 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. Similar to the wireless IC 35, the wireless IC 44 has a transmitter function and a receiver function. The wireless IC 44 receives the data transmitted from the monitoring device 30 via the antenna 42 and the front-end circuit 43, and demodulates it. Then, it transmits the data including the battery monitoring information to the main microcomputer 45. The wireless IC 44 receives the data transmitted from the main microcomputer 45, modulates it, and transmits it 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 then 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, etc. of the wireless communication with other nodes.

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

[0076] The main microcomputer 45 receives data including battery monitoring information transmitted from the wireless IC 44 and executes predetermined processing based on the battery monitoring information. In the present embodiment, the main microcomputer 45 acquires the cell current from the current sensor and executes predetermined processing based on the battery monitoring information and the acquired cell current. 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), state of charge (SOC), and state of health (SOH) of the battery cell 22 based on the battery monitoring information and transmit information including the calculated data to the ECU 14. OCV is an abbreviation for Open Circuit Voltage.

[0077] The main microcomputer 45 performs estimation processing of the internal resistance and open circuit voltage of the battery cell 22 based on, for example, the cell voltage and the cell current. The open circuit voltage is the cell voltage corresponding 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 in the voltage drop corresponding to the internal resistance and the cell current between the open circuit voltage and the cell voltage acquired by the monitoring device 30. 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 estimation processing of the internal resistance and open circuit voltage of the battery cell 22 taking into account, for example, the cell temperature as well.

[0078] The main microcomputer 45 may instruct execution of equalization processing to equalize the voltages of the respective battery cells 22 based on the battery monitoring information. The main microcomputer 45 may acquire the ignition (IG) signal of the vehicle 10 and execute the above-described processing according to the driving state of the vehicle 10. The main microcomputer 45 may execute processing to detect abnormalities in the battery cell 22 or the circuit based on the battery monitoring information, or may transmit abnormality detection information to the ECU 14.

[0079] The sub-microcomputer 46 is a microcomputer including a CPU, a ROM, a RAM, an input / output interface, and a bus for connecting these components. The ROM stores various programs executed by the CPU. The sub-microcomputer 46 executes 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 state of the main microcomputer 45. The sub-microcomputer 46 may monitor the state of the wireless IC 44.

[0080] <Periodic communication processing> Next, based on FIGS. 5 and 6, the periodic communication processing will be described. FIG. 5 is a diagram showing a communication sequence between the monitoring device 30 and the control device 40. The communication sequence may be referred to as a communication flow. In FIG. 5, the wireless communication between one monitoring device 30 and the control device 40 will be described. FIG. 6 shows an example of the periodic communication processing. In FIG. 6, the monitoring IC 33 is shown as MIC 33, the wireless IC 35 is shown as WIC 35, and the control device 40 is shown as ECU 40.

[0081] The battery management system 60 of the present embodiment performs star-type network communication when the number of nodes is 3 or more. That is, the control device 40 performs wireless communication with each of the plurality of monitoring devices 30. Hereinafter, for convenience, the wireless communication between one monitoring device 30 and the control device 40 will be described, but the control device 40 executes the same processing with all the monitoring devices 30.

[0082] When performing wireless communication, as shown in FIG. 5, the monitoring device 30 and the control device 40 first execute connection processing (step S10). In step S10, the monitoring device 30 and the control device 40 perform a wireless communication connection. The connection processing includes the transmission of a packet from the monitoring device 30 to the control device 40. In FIG. 5, the transmission of the packet is indicated by a solid arrow. In FIG. 5, only a part of the packet transmission is shown. For convenience, the packet transmission from the control device 40 is omitted. Details of the connection processing will be described later.

[0083] When the connection process ends, the monitoring device 30 and the control device 40 execute periodic communication processing (step S20). In step S20, the monitoring device 30 periodically performs data communication with the control device 40. As shown in FIG. 6, the control device 40 transmits request data to the monitoring device 30 for which the connection process has been completed (step S21). As an example, the control device 40 transmits request data including a request for acquiring battery monitoring information and a transmission request.

[0084] When the wireless IC 35 of the monitoring device 30 receives the request data, it transmits a request for acquiring battery monitoring information, that is, an acquisition instruction, to the monitoring IC 33 (step S22). The wireless IC 35 of the present embodiment transmits the acquisition request to the monitoring IC 33 via the microcomputer 34.

[0085] When the monitoring IC 33 receives the acquisition request, it executes sensing (step S23). The monitoring IC 33 executes sensing and acquires battery information of each battery cell 22. Further, the monitoring IC 33 executes a failure diagnosis of the circuit.

[0086] Next, the monitoring IC 33 transmits the acquired battery monitoring information to the wireless IC 35 (step S24). In the present embodiment, battery monitoring information including a failure diagnosis result together with the battery information is transmitted. The monitoring IC 33 transmits it to the wireless IC 35 via the microcomputer 34.

[0087] When the wireless IC 35 receives the battery monitoring information acquired by the monitoring IC 33, it transmits transmission data including the battery monitoring information, that is, response data, to the control device 40 (step S25). The control device 40 receives the response data (step S26). The control device 40 periodically performs the above-described data communication with the monitoring device 30 for which the connection has been established.

[0088] The control device 40 executes predetermined processing based on the received response data, that is, the battery monitoring information (step S30).

[0089] Note that although an example in which the monitoring device 30 acquires battery monitoring information based on an acquisition request from the control device 40 has been shown, the present invention is not limited thereto. The monitoring device 30 may autonomously acquire battery monitoring information and transmit the held battery monitoring information to the control device 40 based on a transmission request from the control device 40. According to this, the process of step S22 according to the acquisition request becomes unnecessary.

[0090] <Connection process> Next, based on FIGS. 5 and 7, the connection process will be described. FIG. 7 shows an example of the connection process. In FIG. 7, similar to FIG. 6, the wireless IC 35 is shown as WIC35, and the control device 40 is shown as ECU40.

[0091] The above-described connection process (step S10) includes a connection establishment process (step S1) and a pairing process (step S12) as shown in FIG. 7. The monitoring device 30 and the control device 40 first execute the connection establishment process.

[0092] Specifically, the control device 40 executes a scan operation (step S111), and the monitoring device 30 executes an advertise operation (step S112). The start of the scan operation may be earlier than the start of the advertise operation, may be at substantially the same timing, or may be later than the start of the advertise operation.

[0093] The monitoring device 30 (wireless IC 35) executes an advertise operation to inform the control device 40 of its own existence, and transmits an advertisement packet (ADV_PKT) to the wireless IC 44 of the control device 40. The advertisement packet includes ID information of itself (monitoring device 30) and the control device 40.

[0094] When the control device 40 detects an advertisement packet, that is, the monitoring device 30, by the scan operation, the control device 40 transmits a connection request (CONNECT_REQ) to the detected monitoring device 30 (step S113).

[0095] When the monitoring device 30 receives a connection request, a connection is established between one monitoring device 30 and the control device 40. When the connection is established, the monitoring device 30 stops transmitting the advertisement packet. The monitoring device 30 periodically transmits the advertisement packet until the connection is established.

[0096] When the connection establishment process ends, the pairing process is then executed. The pairing process is a process for performing encrypted data communication. The pairing process includes an exchange process of unique information (step S121). In this exchange process, the unique information held by each other is exchanged and stored. After the execution of the process in step S121, encryption using the exchanged unique information becomes possible. The unique information is, for example, key information or information for generating a key.

[0097] Although an example in which the control device 40 executes a scanning operation and the monitoring device 30 executes an advertising operation has been shown, the present invention is not limited to this. A configuration in which the monitoring device 30 executes a scanning operation and the control device 40 executes an advertising operation may also be used.

[0098] <Timing of Executing the Connection Process> Next, with reference to FIG. 8, the timing of executing the connection process will be described.

[0099] The monitoring device 30 and the control device 40 execute the connection process, for example, at startup. Startup is, for example, when a startup signal such as an IG signal or an on signal of the SMR is supplied. For example, when the IG signal is switched from off to on by a user's operation, startup occurs. 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, electrically connects the battery pack 11 and the PCU 12 when turned on, and disconnects them when turned off. At startup, the connection process is executed between the control device 40 and all the monitoring devices 30 that are connection targets for wireless communication with the control device 40. The connection process CP1 shown in FIG. 8 is the connection process at startup.

[0100] When the wireless communication between the monitoring device 30 and the control device 40 is interrupted, the connection process is executed. That is, reconnection is executed. The control device 40 executes the connection process with the interrupted monitoring device 30 while continuing the data communication with the remaining connected monitoring devices 30. For example, the interruption occurs due to deterioration of the communication environment. The connection process CP2 shown in FIG. 8 is the connection process at the time of communication interruption.

[0101] At startup, it may be, for example, when the operating power is supplied. In a configuration where power is constantly supplied from the battery stack 21 or the battery 15, startup occurs during the vehicle 10 manufacturing process or after component replacement at a repair shop. Also in this case, the connection process is executed at startup. Further, the connection process is also executed when starting up during the sleep period described later and executing the intermittent process.

[0102] <Timing of Transmission of Battery Monitoring Information> Next, based on FIGS. 5 to 7, the timing of transmission of the battery monitoring information will be described.

[0103] As described above, in the periodic communication process, the monitoring device 30 transmits the battery monitoring information to the control device 40 in response to a request (instruction) from the control device 40.

[0104] In addition to the transmission in the periodic communication process, the monitoring device 30 of the present embodiment transmits the battery monitoring information to the control device 40 during the execution period of the connection process as shown in FIG. 5. As described above, in the connection process, the monitoring device 30 transmits a plurality of packets to the control device 40. The monitoring device 30 includes the battery monitoring information in a part of the packets transmitted in the connection process and transmits them.

[0105] The packet that includes the battery monitoring information is not particularly limited. The monitoring device 30 may include the battery monitoring information in the packet during the connection establishment process. For example, the battery monitoring information may be included in the advertisement packet, or may be included in the packet transmitted together with the advertisement packet. When the monitoring device 30 executes the scanning operation, the battery monitoring information may be included in the connection request (CONNECT_REQ) to the control device 40.

[0106] The monitoring device 30 may include the battery monitoring information in the packet during the pairing process. The monitoring device 30 may include the battery monitoring information in the packet transmitted after the completion of the exchange of the unique information. The monitoring device 30 may include the battery monitoring information in the packet transmitted before the completion of the exchange of the unique information during the connection process, or may transmit the battery monitoring information after the completion of the exchange of the unique information. The battery monitoring information may be included in the packet for exchanging the unique information.

[0107] <Timing of acquiring battery monitoring information> Next, based on FIGS. 9, 10, 11, and 12, the timing of acquiring the battery monitoring information transmitted during the connection process will be described. FIG. 9 is a timing chart showing the timing of acquiring the battery monitoring information. FIG. 10 is a diagram showing an example of the communication sequence for acquiring the battery monitoring information. FIG. 11 is a diagram showing an example of the communication sequence for acquiring the battery monitoring information. FIG. 12 is a diagram showing an example of the communication sequence for acquiring the battery monitoring information. FIG. 10 is the communication sequence corresponding to the timing t1 shown in FIG. 9. FIG. 11 is the communication sequence corresponding to the timing t2 shown in FIG. 9. FIG. 12 is the communication sequence corresponding to the timing t3 shown in FIG. 9.

[0108] The control device 40 acquires the battery monitoring information before transmitting the battery monitoring information during the connection process. The control device 40 acquires the battery monitoring information to be transmitted during the connection process at at least one of the timings t1, t2, and t3 shown in FIG. 9.

[0109] Timing t1 is the timing to disconnect the wireless communication between the monitoring device 30 and the control device 40. When disconnecting the wireless communication with the control device 40, the monitoring device 30 transmits the battery monitoring information it holds during the next connection process. As shown in FIG. 10, when disconnecting the wireless communication, the monitoring device 30 and the control device 40 execute a disconnection process (step S40). The disconnection process is executed at the end of the periodic communication process, for example, when the IG signal switches from on to off.

[0110] In the disconnection process, first, the control device 40 transmits data instructing the monitoring device 30 to execute the disconnection process (step S41). When the wireless IC 35 receives the instruction data, the monitoring device 30 executes the disconnection process. As one of the disconnection processes, the wireless IC 35 transmits data instructing the monitoring IC 33 to acquire battery monitoring information (step S42).

[0111] When receiving the instruction, the monitoring IC 33 executes sensing (step S43). The monitoring IC 33 executes sensing to acquire the battery information of each battery cell 22. Also, the monitoring IC 33 executes a circuit fault diagnosis. Then, the monitoring IC 33 transmits the acquired battery monitoring information to the wireless IC 35 (step S44).

[0112] When the wireless IC 35 receives the battery monitoring information acquired by the monitoring IC 33, it holds the battery monitoring information (step S45). The wireless IC 35 holds it by storing the battery monitoring information in the memory. Thus, the acquisition of the battery monitoring information at timing t1 is completed. Then, in the next connection process, the monitoring device 30 (wireless IC 35) includes the battery monitoring information acquired in the disconnection process in a packet and transmits it to the control device 40.

[0113] The battery monitoring information held by the monitoring device 30 during the disconnection process is not limited to the battery monitoring information obtained using the disconnection process as a trigger. The battery monitoring information obtained immediately before executing the disconnection process may be held as the battery monitoring information to be transmitted in the next connection process. In this case, the processes of steps S42 to S44 can be omitted. The battery monitoring information obtained immediately before disconnection is at least for one time. It may be the battery monitoring information for a plurality of times immediately before disconnection.

[0114] Timing t2 is the execution timing of the intermittent process that the monitoring device 30 and the control device 40 start and execute at predetermined time intervals during the sleep period when the wireless communication is disconnected. The monitoring device 30 and the control device 40 execute the intermittent process, for example, while parked. The monitoring device 30 and the control device 40 are periodically activated during the sleep period, for example, by timer control. The monitoring device 30 acquires battery monitoring information during the sleep period.

[0115] As shown in FIG. 11, the monitoring device 30 and the control device 40 start and execute the intermittent process at predetermined time intervals during the sleep period (step S50). The monitoring device 30 and the control device 40 perform, for example, equalization of the SOCs of a plurality of battery cells 22 in the intermittent process. Note that the predetermined time is not limited to a constant (fixed) time at all times.

[0116] In the intermittent process, first, the control device 40 transmits data instructing the monitoring device 30 to execute the equalization process (step S51). When the wireless IC 35 receives the instruction data, it transmits data instructing the monitoring IC 33 to execute the equalization process and acquire the battery monitoring information (step S52).

[0117] When the monitoring IC 33 receives the instruction, it executes sensing (step S53). Also, the monitoring IC 33 executes the equalization process (step S54). The monitoring IC 33 transmits the battery monitoring information acquired by the process of step S53 to the wireless IC 35 (step S55).

[0118] In the equalization process, a process for reducing the voltage variation of a plurality of battery cells 22 is executed. The monitoring IC 33 discharges, for example, a battery cell 22 having a relatively high cell voltage among the plurality of battery cells 22 and charges a battery cell 22 having a relatively low cell voltage. As a result, the SOCs of the plurality of battery cells 22 included in the battery stack 21 are equalized. Alternatively, among the plurality of battery cells 22, a plurality of battery cells 22 excluding the battery cell 22 having the lowest cell voltage may be discharged so as to have a value equal to the lowest cell voltage.

[0119] When the wireless IC 35 receives the battery monitoring information acquired by the monitoring IC 33, the wireless IC 35 holds the battery monitoring information (step S56). The wireless IC 35 holds the battery monitoring information by storing it in the memory. When performing a plurality of intermittent processes until the next connection process, the wireless IC 35 may update and hold the battery monitoring information, or may hold the battery monitoring information for a plurality of times. Thus, the acquisition of the battery monitoring information at timing t2 is completed. Then, in the next connection process, the monitoring device 30 (wireless IC 35) includes the battery monitoring information acquired in the intermittent process in a packet and transmits it to the control device 40.

[0120] Although an example in which sensing is performed before the equalization process is shown, the present invention is not limited to this. Sensing may be performed after the equalization process. The transmission of the battery monitoring information may be performed after the execution of the sensing, or may be performed before the execution of the equalization process.

[0121] Timing t3 is the timing during the connection process before transmitting the battery monitoring information. The monitoring device 30 acquires the battery monitoring information during the connection process. The monitoring device 30 (monitoring IC 33) performs sensing, for example, as shown in FIG. 12, before executing the advertisement operation (step S110). The monitoring device 30 autonomously performs sensing regardless of an instruction from the control device 40 to acquire the battery monitoring information.

[0122] The timing for performing sensing is not limited to the example shown in FIG. 12. It may be performed before transmitting the battery monitoring information. For example, when transmitting the battery monitoring information after the exchange of unique information, sensing may be performed before the exchange of unique information. The monitoring device 30 may perform sensing a plurality of times.

[0123] <Summary of the battery management system> In the present embodiment, the monitoring device 30 and the control device 40 perform connection processing for wireless communication before performing periodic communication of battery monitoring information. Then, the monitoring device 30 includes the battery monitoring information in the packet during the connection processing and transmits it to the control device 40. Therefore, compared with the configuration in which the battery monitoring information is transmitted only after the completion of the connection processing, the timing at which the control device 40 acquires the battery monitoring information can be advanced.

[0124] In the case of wireless communication, the communication speed is slower than that of wired communication, and the communication frequency is often low. By advancing the timing at which the control device 40 acquires the battery monitoring information, the timing at which the ECU 14 acquires information from the control device 40 can be advanced. Therefore, the controllability of the PCU 12 and thus the MG 13 can be improved. In addition, the timing of detecting abnormalities such as abnormalities in the battery cells 22 and abnormalities in the circuit can be advanced.

[0125] As described above, the monitoring device 30 may acquire the battery monitoring information during the intermittent processing. According to this, since the battery monitoring information is acquired before the connection processing, the timing at which the control device 40 acquires the battery monitoring information can be advanced further. In addition, the time required for the connection processing can be shortened. Further, since the battery monitoring information is updated by the intermittent processing at predetermined time intervals, it is possible to suppress the deviation over time while acquiring the battery monitoring information before the connection processing.

[0126] When disconnecting the wireless communication with the control device 40, the monitoring device 30 may acquire battery monitoring information. According to this, since the battery monitoring information is acquired before the connection process, the acquisition timing of the battery monitoring information by the control device 40 can be advanced. Also, the time required for the connection process can be shortened. Further, the load during the intermittent process can be reduced.

[0127] During the execution of the connection process, the monitoring device 30 may acquire battery monitoring information. According to this, the acquired battery monitoring information can be immediately transmitted to the control device 40. That is, the control device 40 can acquire the latest data regarding the battery monitoring information.

[0128] The monitoring device 30 may transmit the battery monitoring information before the exchange of the unique information for the encrypted communication is completed. According to this, the acquisition timing of the battery monitoring information by the control device 40 can be advanced.

[0129] Note that the monitoring device 30 may encrypt the battery monitoring information with a pre-stored encryption key and transmit it to the control device 40. According to this, even if the wireless communication between the monitoring device 30 and the control device 40 is not encrypted, the data itself is encrypted, so the risk of information leakage can be reduced.

[0130] The monitoring device 30 may transmit the battery monitoring information after the exchange of the unique information for the encrypted communication is completed. According to this, since the battery monitoring information is transmitted after the wireless communication between the monitoring device 30 and the control device 40 is encrypted, the risk of information leakage can be reduced.

[0131] In the connection process executed at startup, the monitoring device 30 may include the battery monitoring information in a packet and transmit it to the control device 40. At startup accompanied by the turning on of the IG signal or the intermittent process, the acquisition timing of the battery monitoring information by the control device 40 can be advanced, and the controllability can be improved. Also, at the time of supplying the operating power, the acquisition timing of the battery monitoring information by the control device 40 can be advanced, and the inspection time and the process can be shortened.

[0132] When starting up by turning on the IG signal, the monitoring device 30 may preferentially transmit a part of the battery monitoring information according to the state of the battery acquired immediately before. For example, when the cell voltage acquired immediately before is higher or lower than a predetermined value, the monitoring device 30 may preferentially transmit the cell voltage and / or the fault diagnosis information during the connection process. Thereby, overcharge and overdischarge of the assembled battery 20 can be prevented. The monitoring device 30 may preferentially transmit the cell temperature and / or the fault diagnosis information during the connection process when, for example, the cell temperature acquired immediately before is higher or lower than a predetermined value. Thereby, overheating and freezing of the assembled battery 20 can be prevented.

[0133] When starting up for performing intermittent processing, for example, equalization processing, the monitoring device 30 may preferentially transmit the cell temperature during the connection process. For example, when the battery cell 22 has a short circuit fault, the cell temperature rises even when parked. By preferentially transmitting the cell temperature, overheating of the assembled battery 20 can be prevented. Note that since the cell voltage also shows an abnormal value during a short circuit fault, instead of the cell temperature, the cell voltage may be preferentially transmitted.

[0134] The monitoring device 30 may include the battery monitoring information in the packet and transmit it to the control device 40 in the connection process executed at the time of reconnection after the communication is interrupted. When reconnecting and when the assembled battery 20 is in use, the monitoring device 30 may preferentially transmit the cell voltage and / or the fault diagnosis information during the connection process. Since the assembled battery 20 has been used until before the communication interruption, it is determined that there is no sudden change in the cell temperature, and the cell voltage and / or the fault diagnosis information are prioritized. Thereby, overcharge and overdischarge of the assembled battery 20 can be prevented.

[0135] When reconnecting and when the assembled battery 20 is not in use, the monitoring device 30 may give priority to transmitting the cell temperature during the connection process. Since the assembled battery 20 is not in use, basically battery information is not required, but since it is desired to avoid a temperature rise due to a failure of the battery cell 22, the cell temperature is given priority for transmission. Thereby, overheating of the assembled battery 20 can be prevented. Note that even if the cell voltage is preferentially transmitted instead of the cell temperature, the same effect can be achieved.

[0136] The monitoring device 30 transmits the battery monitoring information at least once during the connection process. The monitoring device 30 may transmit the battery monitoring information a plurality of times during the connection process. The monitoring device 30 may transmit the battery monitoring information a plurality of times in one packet or may transmit them individually. The above-described effects can be enhanced by the battery monitoring information a plurality of times. The monitoring device 30 may transmit, for example, the battery monitoring information for a plurality of times acquired immediately before disconnection. The monitoring device 30 may transmit the battery monitoring information for a plurality of times acquired during a plurality of intermittent processes. The monitoring device 30 may transmit the battery monitoring information for a plurality of times by performing sensing a plurality of times during the connection process.

[0137] <Inspection System> The above-described assembled battery 20 (battery cell 22) is inspected (diagnosed) by the inspection device 80 and the feasibility of reuse is determined while being removed from the vehicle 10. As shown in FIG. 13, the inspection device 80 constructs an inspection system 90 together with the battery management system 60 removed from the vehicle 10 and the assembled battery 20, and inspects the assembled battery 20. The inspection system 90 includes at least one battery management system 60 removed from the vehicle 10 and the inspection device 80.

[0138] The inspection of the battery cell 22 by the inspection device 80 may be performed for each battery management system 60, but it is more efficient to perform it collectively for a plurality of battery management systems 60. In the example shown in FIG. 13, the inspection system 90 includes three battery management systems 60 (60A, 60B, 60C), and the inspection device 80 inspects the battery cells 22 corresponding to the battery management systems 60A, 60B, and 60C collectively.

[0139] In inspection system 90, inspection device 80 performs wireless communication with each of monitoring devices 30 and acquires battery monitoring information for inspection. This battery monitoring information includes at least the above-described battery information and failure diagnosis information. Inspection device 80 may further acquire manufacturing history information. The manufacturing history information is, for example, a manufacturing ID (serial number), a manufacturing date and time, and the like.

[0140] Inspection device 80 inspects the deterioration state and / or abnormality of battery cell 22 and determines the feasibility of reuse based on the inspection result. Inspection device 80 determines whether to reuse battery cell 22 (battery pack 20) or recycle it. Inspection device 80 may be referred to as an inspection tool, a diagnostic device, an external device, or the like.

[0141] Battery management system 60 may include at least monitoring device 30 and sensor 70 in a state of being removed from vehicle 10 together with battery pack 20. That is, battery management system 60 may have a configuration capable of transmitting battery monitoring information to inspection device 80 by wireless communication. Therefore, a configuration without housing 50 and further a configuration without control device 40 may be used. Of course, a configuration equivalent to that when mounted on a vehicle may also be used. When control device 40 is not provided, inspection device 80 may acquire the cell current from the current sensor.

[0142] <Inspection method> Inspection device 80 may inspect (diagnose) the deterioration state and abnormality of battery cell 22 and determine the feasibility of reuse by wirelessly acquiring the battery monitoring information held by monitoring device 30 in a state where battery pack 20 is not connected to a load (not shown), that is, in a state where no power is supplied to the load. That is, based on the battery monitoring information held by monitoring device 30 before establishing a wireless communication connection with inspection device 80, inspection device 80 may inspect (diagnose) the deterioration state and abnormality of battery cell 22 and determine the feasibility of reuse. Inspection device 80 may determine the feasibility of reuse based on the battery monitoring information acquired by monitoring device 30 in a state where no power is supplied to the load. For example, the feasibility of reuse may be determined based on the cell voltage, that is, the open-circuit voltage.

[0143] The inspection device 80 inspects (judges) the deterioration state of the battery cell 22, for example, based on the acquired manufacturing history information. The inspection device 80 inspects the deterioration state of the battery cell 22, for example, based on the elapsed time since the manufacturing date. The inspection device 80 may inspect the presence or absence of abnormalities based on the failure diagnosis information. The inspection device 80 may estimate the internal resistance, SOH, etc. of the battery cell 22 based on battery information such as the cell voltage, and inspect the deterioration state of the battery cell 22. For example, the internal resistance increases as the battery cell 22 deteriorates.

[0144] The inspection device 80 may inspect (diagnose) the deterioration state and abnormalities of the battery cell 22, including the inspection results in the energized state of the assembled battery 20, and determine whether reuse is possible. Specifically, the inspection device 80 may acquire battery monitoring information from the monitoring device 30 in a state where the assembled battery 20 is connected to the load, that is, in a state of being energized to the load, and determine whether reuse is possible.

[0145] The inspection device 80 inspects the deterioration state of the battery cell 22, for example, by estimating the internal resistance, SOH, etc. of the battery cell 22 based on the acquired battery information. The inspection device 80 inspects the abnormalities of the battery cell 22 and the monitoring device 30, for example, based on the failure diagnosis information. When collectively inspecting a plurality of battery management systems 60, the assembled batteries 20 (battery stacks 21) of the plurality of battery management systems 60 are, for example, connected in series.

[0146] FIG. 14 shows the communication sequence between the monitoring device 30r and the inspection device 80r in the reference example. In the reference example, an "r" is added to the end of the reference numerals of the related elements of the present embodiment. Also, for the step numbers, the same step numbers as those in FIG. 15 described later are given. In FIG. 14, the monitoring device 30r is shown as SBM30r. In FIG. 14, a part of the packet transmission is indicated by an arrow. For the sake of convenience, the packet transmission from the inspection device 80 is omitted. The number of packets transmitted shown in the figure is merely an example.

[0147] In any case of performing the above-described inspections, the monitoring device 30r and the inspection device 80r first execute a wireless communication connection process (step S60). The connection process in step S60 is the same process as the connection process in step S10.

[0148] After the connection process ends, an inspection communication process is executed (step S70). In this communication process, the monitoring device 30r transmits battery monitoring information to the inspection device 80r. In the case of the reference example, the inspection device 80r cannot obtain battery monitoring information unless the connection process has ended, regardless of which inspection is being performed. Thus, there is a problem that the waiting time until the battery monitoring information is obtained is long. In particular, when a plurality of battery packs 20 are inspected together, the inspection efficiency decreases due to the accumulation of the waiting time.

[0149] FIG. 15 shows an example of a communication sequence between the monitoring device 30 included in the battery management system 60 of the present embodiment and the inspection device 80. In FIG. 15, the monitoring device 30 is shown as SBM30. In FIG. 15, a part of the packet transmission is indicated by an arrow. For convenience, the packet transmission from the inspection device 80 is omitted. The number of packets transmitted shown in the figure is merely an example.

[0150] When performing wireless communication, the monitoring device 30 and the inspection device 80 first execute a connection process (step S60). The connection process in step S60 is the same as the connection process in step S10, that is, the connection process between the monitoring device 30 and the control device 40. In the connection process, the inspection device 80 functions in the same manner as the above-described control device 40. In the connection process, the monitoring device 30 transmits a plurality of packets to the inspection device 80. The monitoring device 30 includes battery monitoring information in a part of the packets transmitted in the connection process and transmits them.

[0151] Although the illustration is omitted, for example, the inspection device 80 executes a scanning operation, and the monitoring device 30 executes an advertising operation. The monitoring device 30 may include battery monitoring information in, for example, an advertisement packet, or may include battery monitoring information in a packet transmitted together with the advertisement packet. The monitoring device 30 may include battery monitoring information in a packet transmitted before the exchange of unique information for encryption during the connection process, or may transmit the battery monitoring information after the exchange of unique information.

[0152] In the example shown in FIG. 15, the monitoring device 30 transmits, for example, battery monitoring information at least once during the connection process. This battery monitoring information is the battery monitoring information held by the monitoring device 30 before performing the connection process. The battery monitoring information includes the battery information and the fault diagnosis information described above. The inspection device 80 inspects (diagnoses) the deterioration state and abnormalities of the battery cell 22 and determines the feasibility of reuse based only on the battery monitoring information acquired during the connection process. Note that the monitoring device 30 may transmit the battery monitoring information a plurality of times during the connection process.

[0153] In this case, the monitoring device 30 transmits the battery monitoring information during the connection process. Thereby, the timing for the inspection device 80 to acquire the battery monitoring information can be advanced. Also, it is not necessary to perform the communication process for inspection shown in FIG. 14. Therefore, the time required for the inspection and reuse determination of the battery cell 22 can be shortened. The inspection device 80 performs wireless communication in the same manner with a plurality of monitoring devices 30 and acquires the battery monitoring information. Therefore, when determining the feasibility of reuse for a large number of battery cells 22, the inspection time can be significantly shortened. Note that the monitoring device 30 may transmit the battery monitoring information and / or the manufacturing history information. The inspection device 80 executes an inspection based on the acquired information.

[0154] In the example shown in FIG. 16, after the connection process, the monitoring device 30 executes communication processing for inspection (step S70). The communication processing in step S70 is the same as the processing in step S20, that is, the periodic communication processing between the monitoring device 30 and the control device 40. The inspection device 80 periodically acquires battery monitoring information from the monitoring device 30.

[0155] During the connection process, the monitoring device 30 transmits, for example, battery monitoring information at least once. This battery monitoring information is the battery monitoring information held by the monitoring device 30 before the connection process. The battery monitoring information includes the above-described battery information and failure diagnosis information. As shown in FIG. 16, the monitoring device 30 may transmit battery monitoring information a plurality of times during the connection process.

[0156] Also in this case, the monitoring device 30 transmits battery monitoring information during the connection process. Thereby, the timing for the inspection device 80 to acquire the battery monitoring information can be advanced. Therefore, the time required for the inspection and reuse determination of the battery cell 22 can be shortened. The inspection device 80 performs wireless communication in the same manner with a plurality of monitoring devices 30 and acquires battery monitoring information. Therefore, when determining the reusability of a large number of battery cells 22, the inspection time can be significantly shortened. Note that the monitoring device 30 may transmit battery monitoring information and / or manufacturing history information. The inspection device 80 executes an inspection based on the acquired information.

[0157] The situation where the battery pack 20 is inspected by the inspection device 80 with the battery pack 20 and the battery management system 60 removed from the moving body is not limited to the inspection of the reusability of the battery pack 20. For example, it may be an inspection during the manufacture of the battery pack 11, an inspection at a repair factory, etc. During these inspections, the monitoring device 30 may include the battery monitoring information in the packet during the period of executing the wireless communication connection process with the inspection device 80 and transmit it to the inspection device 80.

[0158] (Other embodiments) The disclosure in this specification, drawings, etc. is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and modifications by those skilled in the art based thereon. For example, the disclosure is not limited to the combination of parts and / or elements shown in the embodiments. The disclosure can be implemented by various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes those in which parts and / or elements of the embodiments are omitted. The disclosure includes the replacement or combination of parts and / or elements between one embodiment and another. The disclosed technical scope is not limited to the description of the embodiments. Some of the disclosed technical scopes are indicated by the description of the claims and should be construed to include all changes within the meaning and scope equivalent to the description of the claims.

[0159] The disclosure in the specification, drawings, etc. is not limited by the description of the claims. The disclosure in the specification, drawings, etc. includes the technical idea described in the claims and extends to more diverse and extensive technical ideas than the technical idea described in the claims. Therefore, various technical ideas can be extracted from the disclosure in the specification, drawings, etc. without being restricted by the description of the claims.

[0160] When an element or layer is referred to as "above," "connected to," "attached to," or "coupled to," it can be directly above, connected to, attached to, or coupled to another element or layer, and there may also be intervening elements or intervening layers. In contrast, when an element is referred to as "directly above," "directly connected to," "directly attached to," or "directly coupled to" another element or layer, there are no intervening elements or intervening layers. Other words used to describe the relationship between elements should be interpreted 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.

[0161] Spatially relative terms such as "inner," "outer," "beneath," "below," "lower," "above," "upper," etc. are used herein to facilitate description of the relationship of one element or feature to another element or feature as illustrated. Spatially relative terms can be intended to encompass different orientations of the device during use or operation in addition to the orientation depicted in the drawings. For example, if the device in the figures is turned over, an element described as "below" or "beneath" another element or feature will be oriented "above" the other element or feature. Thus, the term "below" can encompass both an orientation of above and below. The device may be oriented in other directions (rotated 90 degrees or other orientations), and the spatially relative descriptors used in this specification will be interpreted accordingly.

[0162] The devices, systems, and methods described in this disclosure may be implemented by a dedicated computer configured to program a processor to execute one or more functions embodied by a computer program. Alternatively, the devices and methods described in this disclosure may be implemented by dedicated hardware logic circuits. Or, the devices and methods described in this disclosure may be implemented by one or more dedicated computers configured by a combination of a processor that executes a computer program and one or more hardware logic circuits. Also, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions to be executed by a computer.

[0163] For example, although an example in which the monitoring device 30 includes the microcomputer 34 has been shown, it is not limited thereto. As shown in FIG. 17, a battery management system 60 having a configuration in which the monitoring device 30 does not include the microcomputer 34 may be employed. FIG. 17 corresponds to FIG. 4. In this configuration, the wireless IC 35 transmits and receives data to and from the monitoring IC 33. Regarding the scheduling control of sensing and self-diagnosis by the monitoring IC 33, the wireless IC 35 may execute it, or the main microcomputer 45 of the control device 40 may execute it.

[0164] Although an example in which the monitoring device 30 is arranged for each battery stack 21 has been shown, it is not limited thereto. For example, one monitoring device 30 may be arranged for a plurality of battery stacks 21. A plurality of monitoring devices 30 may be arranged for one battery stack 21.

[0165] Although an example in which the battery pack 11 includes one control device 40 has been shown, it is not limited thereto. A plurality of control devices 40 may be included. That is, the battery pack 11 may include one or more monitoring devices 30 and one or more control devices 40. The battery management system 60 may include a plurality of wireless communication systems constructed between one control device 40 and one or more monitoring devices 30.

[0166] Although an example in which the control device 40 includes one wireless IC 44 has been shown, the present invention is not limited thereto. The control device 40 may include a plurality of wireless ICs 44. Each of the plurality of wireless ICs 44 may perform wireless communication with a plurality of different monitoring devices 30.

[0167] Although an example in which the monitoring device 30 includes one monitoring IC 33 has been shown, the present invention is not limited thereto. The monitoring device 30 may include a plurality of monitoring ICs 33. In this case, a wireless IC 35 may be provided for each monitoring IC 33, or one wireless IC 35 may be provided for a plurality of monitoring ICs 33.

[0168] Although an example in which the control device 40 is disposed within the housing 50 has been shown, the present invention is not limited thereto. The control device 40 may be disposed outside the housing 50.

[0169] The arrangement and number of the battery stack 21 and the battery cells 22 that constitute the battery pack 20 are not limited to the above-described examples. In the battery pack 11, the arrangement of the monitoring device 30 and / or the control device 40 is not limited to the above-described examples.

Description of Reference Numerals

[0170] 10…Vehicle, 11…Battery pack, 12…PCU, 13…MG, 14…ECU, 15…Battery, 20…Battery pack, 21…Battery stack, 22…Battery cell, 23…Bus bar unit, 24…Bus bar, 25…Positive terminal, 26…Negative terminal, 27…Bus bar cover, 30…Monitoring device, 31, 311, 312, 313…Power supply circuit, 32…Multiplexer, 33…Monitoring IC, 34…Microcomputer, 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 microcomputer, 46…Sub-microcomputer, 50…Housing, 60…Battery management system, 70…Sensor, 80…Inspection device, 90…Inspection system

Claims

1. One or more monitoring devices (30) arranged within a housing (50) that houses batteries (20, 21, 22), and that acquire and monitor battery monitoring information including information indicating the state of the batteries; A control device (40) that performs wireless communication with the monitoring device and executes a predetermined process based on the battery monitoring information, The monitoring device is Acquiring a plurality of the battery monitoring information including a cell voltage which is a voltage of a battery cell constituting the battery and a cell temperature which is a temperature of the battery cell, During a period in which a wireless communication connection process is being executed with the control device, including the battery monitoring information in a packet and transmitting it to the control device, A battery management system that preferentially transmits the cell voltage among the plurality of the battery monitoring information during a period of the connection process executed when starting up the monitoring device and the control device by supplying a start signal.

2. The monitoring device and the control device start up at predetermined intervals during a sleep period and execute intermittent processing, During a period of the connection process executed when starting up for the intermittent processing, the monitoring device preferentially transmits the cell temperature among the plurality of the battery monitoring information. The battery management system according to claim 1.

3. When reconnecting after communication between the monitoring device and the control device has been interrupted, and during a period of the connection process executed when the battery is in use, the monitoring device preferentially transmits the cell voltage among the plurality of the battery monitoring information. The battery management system according to claim 1.

4. When reconnecting after communication between the monitoring device and the control device has been interrupted, and during a period of the connection process executed when the battery is not in use, the monitoring device preferentially transmits the cell temperature among the plurality of the battery monitoring information. The battery management system according to claim 1.

5. In the battery management system according to claim 1, The monitoring device and the control device start up at predetermined intervals during a sleep period and execute intermittent processing, The monitoring device transmits the battery monitoring information acquired during the intermittent processing to the control device during a period of the connection process. A battery management system.

6. In the battery management system according to claim 1, The monitoring device transmits the battery monitoring information held when disconnecting wireless communication with the control device to the control device during a period of the connection process. A battery management system.

7. In the battery management system according to claim 1, The monitoring device acquires the battery monitoring information and transmits it to the control device during the connection process. A battery management system.

8. In the battery management system according to any one of claims 1 to 7, The connection process includes the exchange of unique information for encrypted communication, The monitoring device transmits the battery monitoring information before the exchange of the unique information is completed. A battery management system.

9. In the battery management system according to any one of claims 1 to 7, The connection process includes the exchange of unique information for encrypted communication, The monitoring device transmits the battery monitoring information after the exchange of the unique information is completed. A battery management system.

10. In the battery management system according to any one of claims 1 to 9 mounted on a moving body, In a state of being removed from the moving body together with the battery, The monitoring device includes the battery monitoring information and / or the manufacturing history information in a packet during a period of executing a wireless communication connection process with the inspection device (80) and transmits it to the inspection device. A battery management system.

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