Monitoring system

Abstract

A monitoring system includes monitoring devices (30) disposed in a monitored device, and a controller (40) that wirelessly communicates with the monitoring devices to obtain monitoring information. In a running state of the monitored device, the controller and the monitoring devices establish respective connections in which the controller, acting as a communication master, performs wireless communication with each of the monitoring devices acting as a communication slave. In a non-running state of the monitored device, the controller and the monitoring devices maintain communication between the controller and the monitoring devices by establishing a sequential connection. In the sequential connection, the controller, acting as a communication master, performs wireless communication with one of the monitoring devices acting as a communication slave, and the one of the monitoring devices acting as a communication master sequentially performs wireless communication with another one of the monitoring devices acting as a communication slave.

Description

Technical Field

[0001] This disclosure relates to a monitoring system for monitoring monitored equipment (such as battery assemblies). Background Technology

[0002] For example, a battery control system is described in Patent Document 1 (JP 6093448 B, corresponding to US 2016 / 0268642 A1). This battery control system includes battery cell management devices and assembled battery management devices. The battery cell management devices acquire measurements of the state of charge of the battery cells in a corresponding battery cell group. The assembled battery management devices perform wireless communication with the battery cell management devices. Summary of the Invention

[0003] In the aforementioned battery control system, when the vehicle's main switch is off, the battery pack enters a non-operating state, in which no power supply is required to the in-vehicle system, and wireless communication between the battery pack management device and each battery cell management device is disabled. When the vehicle's main switch is on and the battery pack enters the operating state, communication between the battery pack management device and each battery cell management device needs to be re-established. However, because establishing communication takes time, the battery pack management device and each battery cell management device cannot quickly begin communication when the battery pack enters the operating state.

[0004] Therefore, the inventors have conducted research on maintaining communication between each monitoring device monitoring a device such as the aforementioned assembled battery and a controller communicatively connected to the monitoring device, even when the monitored device is not in operation. Maintaining communication between the controller and the monitoring device while the monitored device is not in operation allows for rapid initiation of communication regarding monitoring information about the monitored device when the monitored device enters operation.

[0005] However, if the controller maintains communication with the monitoring device even when the monitored device is not in operation, the controller's power consumption may exceed that of each individual monitoring device. This power consumption difference can become problematic if the power supply for the controller and the power supply for the monitoring devices are different.

[0006] The purpose of this disclosure is to provide a monitoring system that maintains communication between the controller and the monitoring device even when the monitored device is not in operation, while reducing power consumption in the controller.

[0007] According to one aspect of this disclosure, a monitoring system includes a monitoring device disposed in and monitoring the monitored device, and a controller configured to wirelessly communicate with the monitoring device to obtain monitoring information of the monitored device from the monitoring device. The monitored device can switch between an operating state and a non-operating state. In the operating state of the monitored device, the controller and the monitoring device establish respective connections, wherein the controller, acting as a communication master, performs wireless communication with each monitoring device, acting as a communication slave. In the non-operating state of the monitored device, the controller and the monitoring device maintain communication by establishing sequential connections. In the sequential connection, the controller, acting as a communication master, performs wireless communication with one of the monitoring devices, acting as a communication slave, and one of the monitoring devices, acting as a communication master, sequentially performs wireless communication with another monitoring device among the monitoring devices acting as communication slaves.

[0008] As described above, in the non-operational state of the non-monitored devices, the controller acts as the communication master for one of the monitoring devices. Regarding the remaining monitoring devices, one of the monitoring devices then acts as the communication master for another. As described above, by switching the communication mode between the controller and the monitoring devices, power consumption in the controller can be reduced while maintaining communication between them. Attached Figure Description

[0009] Figure 1 This is a diagram showing a vehicle including a battery pack.

[0010] Figure 2 This is a three-dimensional diagram showing the schematic structure of the battery pack.

[0011] Figure 3 This is a top view showing the assembled battery.

[0012] Figure 4 This is a block diagram showing the structure of the battery management system.

[0013] Figure 5 This is a diagram showing the communication sequence between the monitoring device and the controller.

[0014] Figure 6 This is a diagram illustrating the connection process.

[0015] Figure 7 This is a diagram illustrating a periodic communication process.

[0016] Figure 8 Figure (a) shows the communication mode between the controller and the monitoring device in the operating state of the assembled battery according to the first embodiment, and Figure (b) shows the communication mode between the controller and the monitoring device in the non-operating state of the assembled battery.

[0017] Figure 9This is a flowchart illustrating the process in the controller and monitoring device according to the first embodiment.

[0018] Figure 10 This is a diagram illustrating the communication mode between the controller and the monitoring device in the non-operational state of the assembled battery according to the second embodiment.

[0019] Figure 11 This is a flowchart illustrating the process in the controller and monitoring device according to the second embodiment.

[0020] Figure 12 This is a diagram illustrating the communication mode between the controller and the monitoring device in the non-operational state of the assembled battery according to the third embodiment.

[0021] Figure 13 This is a flowchart illustrating the processes in the controller and monitoring device of the third embodiment. Detailed Implementation

[0022] In the following description, several embodiments will be described with reference to the accompanying drawings. Identical or corresponding elements in the embodiments are assigned the same reference numerals and will not be described again thereto. When only a portion of the structure is described in one embodiment, the other portions of the structure may be described in relation to the corresponding structure in another embodiment preceding that embodiment. Furthermore, not only combinations of structures explicitly shown in the description of the corresponding embodiments, but also structures from multiple embodiments may be partially combined, even if they are not explicitly shown, provided that such combination is not particularly difficult.

[0023] (First Embodiment)

[0024] First, refer to Figure 1 The structure of a vehicle on which a battery management system, which serves as a monitoring system according to this embodiment, is installed will be described. Specifically, a vehicle relating to a battery pack including a battery management system will be described. Figure 1 This is a schematic diagram illustrating the 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). Battery management systems can also be applied to mobile bodies other than vehicles, and for example, to flying vehicles such as drones, ships, construction machinery, or agricultural machinery. Battery management systems can also be applied to stationary batteries (storage batteries) for home, commercial, and other applications.

[0025] <Vehicles>

[0026] like Figure 1As shown, vehicle 10 includes battery pack (BAT) 11, PCU 12, MG 13, and 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".

[0027] Battery pack 11 includes assembled battery 20 (described later) and provides a rechargeable and dischargeable DC voltage source. Battery pack 11 supplies power to the electrical loads of vehicle 10. For example, battery pack 11 supplies power to MG 13 via PCU 12. Battery pack 11 is charged via PCU 12. Battery pack 11 may be referred to as the main machine battery.

[0028] For example, such as Figure 1 As shown, the battery pack 11 is located in the front compartment of the vehicle 10. The battery pack 11 can also be located in the rear compartment, under the seats, under the floor, etc. For example, in the case of a hybrid electric vehicle, the compartment where the engine is located can be referred to as the engine compartment or engine room.

[0029] The temperature of the battery pack 11 is regulated by air flowing into the moving vehicle 10 and by cooling air supplied from a fan mounted on the vehicle 10. The temperature of the battery pack 11 can also be regulated by coolant circulating within the vehicle 10. These temperature regulations reduce excessive temperature variations in the battery pack 11. The battery pack 11 can be easily coupled to a component with a large heat capacity, such as the body of the vehicle 10, via thermal conductivity.

[0030] PCU 12 performs bidirectional power conversion between battery pack 11 and MG 13 based on control signals from ECU 14. PCU 12 can be referred to as a power converter. PCU 12 may include an inverter and a converter. The converter is located in the energization path between battery pack 11 and the inverter. The converter has the function of boosting and reducing DC voltage. The inverter converts the DC voltage boosted by the converter into AC voltage such as three-phase AC voltage and outputs the AC voltage to MG 13. The inverter converts the power generated by MG 13 into DC voltage and outputs DC voltage to the converter. The converter uses the DC voltage obtained by reducing the DC voltage output from the inverter to charge the assembled battery 20 of battery pack 11.

[0031] MG 13 is an AC rotary motor, such as a three-phase AC synchronous motor, in which permanent magnets are embedded in the rotor. MG 13 serves as the drive source for the vehicle 10, i.e., an electric motor. MG 13 is driven by PCU 12 to generate rotational driving force. The driving force generated by MG 13 is transmitted to the drive wheels. MG 13 acts as a generator and performs regenerative power generation when the vehicle 10 brakes. The electricity generated by MG 13 is supplied to battery pack 11 via PCU 12 and stored in the assembled batteries 20 within battery pack 11.

[0032] ECU 14 includes a computer, comprising a processor, memory, input / output interfaces, and buses connecting these components. The processor is hardware used for arithmetic operations. The processor includes, for example, a CPU as its core. "CPU" is an abbreviation for "Central Processing Unit." Memory is a non-transitory tangible storage medium that non-transitorily stores computer-readable programs, data, etc. Memory stores various programs to be executed by the processor.

[0033] ECU 14 obtains information about assembled battery 20 from battery pack 11, for example, and controls PCU 12 to control the drive of MG13 and the charging and discharging of battery pack 11. ECU 14 can obtain information from battery pack 11 such as the voltage, temperature, current, SOC, and SOH of assembled battery 20. ECU 14 can obtain battery information, such as the voltage, temperature, and current of assembled battery 20, and calculate SOC and SOH. "SOC" is an abbreviation for "State of Charge". "SOH" is an abbreviation for "Health Status".

[0034] The processor of ECU 14 executes, for example, multiple instructions contained in the PCU control program stored in memory. As a result, ECU 14 constructs multiple functional units for controlling PCU 12. As described above, in ECU 14, the program stored in memory causes the processor to execute multiple instructions, thereby constructing functional units. ECU 14 may be referred to as an EVECU.

[0035] <Battery Pack>

[0036] Next, we will refer to Figure 2 and Figure 3 Describe a structural example of battery pack 11. Figure 2 This is a schematic perspective view of the interior of battery pack 11. Figure 2 In the middle, the outer shell 50 is represented by a double-dotted line. Figure 3 It is a top view showing the top surface of each battery stack.

[0037] like Figure 2 As shown, the battery pack 11 includes assembled batteries 20, monitoring equipment 30, controller 40, and housing 50. In the following text, as... Figure 2 As shown, on the mounting surface of the housing 50 attached to the vehicle 10, the longitudinal direction is referred to as the X direction, and the transverse direction as the Y direction. This mounting surface is one of the surfaces of the housing 50 and has a substantially cuboid shape. Figure 2 In this embodiment, the lower surface of the housing 50 is the mounting surface. The vertical direction perpendicular to the mounting surface is called the Z-direction. The X, Y, and Z directions are arranged to be orthogonal to each other. In this embodiment, the left-right direction of the vehicle 10 corresponds to the X-direction, the front-rear direction of the vehicle 10 corresponds to the Y-direction, and the vertical direction of the vehicle 10 corresponds to the Z-direction. Figure 2 and Figure 3 The arrangement is merely an example, and the battery pack 11 can be arranged in any way relative to the vehicle 10.

[0038] The assembled battery 20 includes battery stacks 21 arranged side-by-side in the X direction. The battery stacks 21 may be referred to as battery blocks, battery modules, etc. The assembled battery 20 is formed by battery stacks 21 connected in series and / or in parallel. In this embodiment, the battery stacks 21 are connected in series.

[0039] Each battery stack 21 has a battery cell 22. The battery cell 22 is housed in a case. As a result, the relative positions of the 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 completely located between the wall surface of the case and the battery cell 22.

[0040] There are no particular restrictions on the form of the fixing components, as long as the relative positions of the battery cells 22 can be fixed. For example, a structure in which the battery cells 22 are constrained by a strip-shaped band can be used. In this case, a separator for maintaining the separation distance between the battery cells 22 can be placed between the battery cells 22.

[0041] Each battery stack 21 includes battery cells 22 connected in series. In this embodiment, the battery stack 21 contains battery cells 22 arranged side-by-side along the Y direction connected in series. The assembled battery 20 provides the aforementioned DC voltage source. The assembled battery 20, battery stack 21, and battery cells 22 correspond to batteries.

[0042] Each battery cell 22 is a secondary battery that generates an electromotive force through a chemical reaction. As a secondary battery, lithium-ion secondary batteries, nickel-metal hydride secondary batteries, organic radical batteries, etc., can be used. Lithium-ion secondary batteries use lithium as the charge carrier. Secondary batteries that can be used as battery cells 22 can be not only secondary batteries with liquid electrolytes, but also so-called all-solid-state batteries using solid electrolytes.

[0043] Battery cell 22 includes a power generation element and a battery casing housing the power generation element. For example... Figure 3 As shown, the battery casing of each battery cell 22 is formed in a flat shape. The battery casing has two end faces facing the Z direction and a total of four sides, including two sides facing the X direction and two sides facing the Y direction. The battery casing of this embodiment is made of metal.

[0044] The battery cells 22 are stacked such that the sides of the battery casings are in contact with each other in the Y direction. Each battery cell 22 has a positive terminal 25 and a negative terminal 26 at different ends in the X direction. The positive terminal 25 and the negative terminal 26 protrude in the Z direction, more specifically in the upward Z+ direction. For each battery cell 22, the positions of the positive terminal 25 and the negative terminal 26 from their protruding end faces are the same in the Z direction. The battery cells 22 are stacked such that the positive terminal 25 and the negative terminal 26 are arranged alternately in the Y direction.

[0045] Linear bus bar units 23 are disposed at both ends of the upper surface of each battery stack 21 in the X direction. The bus bar units 23 are disposed at both ends in the X direction of the positive terminal 25 and the negative terminal 26 protruding from the end faces of their battery housings. That is, a pair of bus bar units 23 are disposed in each battery stack 21.

[0046] Each busbar unit 23 includes a busbar 24 electrically connecting positive terminals 25 and negative terminals 26 arranged alternately along the Y direction, and a busbar cover 27 covering the busbar 24. Each busbar 24 is a sheet material made of a metal with good conductivity (e.g., copper or aluminum). The busbar 24 electrically connects the positive terminals 25 and negative terminals 26 of battery cells 22 that are adjacent to each other in the Y direction. As a result, in each battery stack 21, the battery cells 22 are connected in series.

[0047] According to this connection structure, in each battery stack 21, one of the two battery cells 22 located at opposite ends of the battery cells 22 arranged along the Y direction has the highest potential, while the other has the lowest potential. A predetermined cable is connected to at least one of the positive terminal 25 of the battery cell 22 with the highest potential and the negative terminal 26 of the battery cell 22 with the lowest potential.

[0048] like Figure 2 As shown, the battery stacks 21 are arranged along the X direction. The positive terminal 25 of the battery cell 22 with the highest potential in one of the two adjacent battery stacks 21 in the X direction is connected via a predetermined cable to the negative terminal 26 of the battery cell 22 with the lowest potential in the other battery stack 21. Therefore, the battery stacks 21 are connected in series.

[0049] According to this connection structure, one of the two battery stacks 21 located at opposite ends along the X direction becomes the highest potential battery stack 21, and the other becomes the lowest potential battery stack 21. The output terminal is connected to the positive terminal 25 of the battery cell 22 with the highest potential in the highest potential battery stack 21. The output terminal is connected to the negative terminal 26 of the battery cell 22 with the lowest potential in the lowest potential battery stack 21. These two output terminals are connected to electrical equipment installed on the vehicle 10, such as a PCU 12.

[0050] Two battery stacks 21 adjacent to each other in the X direction may not be electrically connected via a predetermined cable. Any two battery stacks 21 arranged along the X direction may be electrically connected via a predetermined cable. The positive terminal 25 and the negative terminal 26, which are electrically connected via a predetermined cable, may be in the same or different positions in the Y direction. That is, the positive terminal 25 and the negative terminal 26 may be at least partially facing each other or not facing each other at all in the X direction. One of the positive terminal 25 and the negative terminal 26 may be at least partially located or not located at all in the projection area obtained by projecting the other of the positive terminal 25 and the negative terminal 26 in the X direction.

[0051] Each busbar cover 27 is formed of an electrically insulating material such as resin. The busbar covers 27 are arranged linearly along the Y direction from one end of the battery stack 21 to the other, such that the busbar covers 27 cover multiple busbars 24. The busbar covers 27 may have partition walls. The partition walls enhance the insulation between two adjacent busbars 24 in the Y direction.

[0052] Monitoring device 30 is specifically designed for battery stack 21. For example... Figure 2 As shown, a monitoring device 30 is arranged between a pair of busbar units 23 in each battery stack 21. The monitoring device 30 faces the end face of the battery casing in the Z direction, from which the positive terminal 25 and the negative terminal 26 protrude. The monitoring device 30 and the end face can be separated from each other in the Z direction, or they can face each other and be in contact in the Z direction. An object such as an insulating sheet can be placed between the monitoring device 30 and the end face.

[0053] The monitoring device 30 is fixed to the busbar unit 23 with screws or the like. As described later, the monitoring device 30 is capable of wireless communication with the controller 40. The antenna 37 included in the monitoring device 30, described later, is configured so as not to overlap with the busbar unit 23 in the Z direction (i.e., to protrude more than the busbar unit 23 in the Z direction).

[0054] The material of the coupling member (e.g., screw) used to couple the monitoring device 30 and the busbar unit 23 can be, for example, a non-magnetic material, in order to avoid interference with wireless communication. Besides screws, other components disposed in the battery stack 21 that do not require special magnetism can also be made of non-magnetic materials.

[0055] In this embodiment, the monitoring device 30 is arranged along the X direction. The monitoring devices 30 are positioned identically in the Y direction. Through this configuration, the extension of the separation interval of the monitoring devices 30 is reduced.

[0056] The controller 40 is attached to the outer surface of the battery stack 21 located at one end in the X direction. The controller 40 is capable of performing wireless communication with each monitoring device 30. The antenna 42 included in the controller 40, described later, is positioned in the Z direction at approximately the same height as the antenna 37 of the monitoring device 30. That is, the antenna 42 of the controller 40 is positioned to protrude further than the busbar unit 23 in the Z direction.

[0057] In battery pack 11, monitoring device 30 and controller 40 provide a battery management system 60, which will be described later. That is, battery pack 11 includes battery management system 60.

[0058] To prevent the battery pack 11 from becoming a source of electromagnetic noise, it may be necessary to reduce the leakage of radio waves from wireless communication to the outside of the communication space where wireless communication between the monitoring device 30 and the controller 40 is performed. Conversely, to reduce interference with wireless communication, it may be necessary to reduce electromagnetic noise entering the communication space.

[0059] For this reason, for example, the housing 50 can reflect electromagnetic waves. The housing 50 includes materials for reflecting electromagnetic waves, described below as examples. For example, the housing 50 includes a magnetic material such as a metal. The housing 50 includes a resin material and a magnetic material covering the surface of the resin material. The housing 50 includes a resin material and a magnetic material embedded in the resin material. The housing 50 includes carbon fiber. The housing 50 may be able to absorb electromagnetic waves rather than reflect them.

[0060] The housing 50 may have an opening communicating with both an internal receiving space and an external space (external space) of the housing 50. The opening is defined by a coupling surface that lies between and connects the inner and outer surfaces of the housing 50. For example, the opening may be used for ventilation, power line routing, and signal line routing. In structures with openings, a cover may be provided over the opening. The cover prevents communication between the receiving space and the external space. The cover may block all or part of the opening.

[0061] For example, the cover may be disposed on any one of the inner surface, outer surface, or coupling surface of the housing 50. The cover may be configured to face the hole to cover it, rather than being disposed on any one of the inner surface, outer surface, or coupling surface. When the cover and the hole are separated from each other, the separation gap between them is shorter than the length of the hole. The length of the hole is the dimension between the inner and outer surfaces, or the dimension in a direction orthogonal to the distance between the inner and outer surfaces.

[0062] The cover can be, for example, a connector, an electromagnetic shielding component, a sealing material, etc. The cover includes materials described below as examples. The cover includes, for example, a magnetic material, such as a metal. The cover includes a resin material and a magnetic material covering the surface of the resin material. The cover includes a resin material and a magnetic material embedded in the resin material. The cover includes carbon fiber. The cover includes a resin material.

[0063] The opening in the housing 50 can be covered by at least one of the components housed within the housing space of the housing 50. The separation gap between the housed component and the opening is shorter than the length of the opening. Power lines and signal lines can be arranged across the housing space and the external space, while being held by an electrically insulating member forming part of the wall of the housing 50.

[0064] Battery Management System

[0065] Next, we will refer to Figure 4 Describe a schematic structure of a battery management system. Figure 4 This is a block diagram showing the structure of the battery management system.

[0066] like Figure 4 As shown, the battery management system 60 includes a monitoring device (SBM) 30 and a controller (ECU) 40. In the following text, the monitoring device may be referred to as the SBM. The controller 40 may be referred to as the battery ECU or BMU. BMU is an abbreviation for Battery Management Unit. The battery management system 60 is a system that uses wireless communication to manage the battery. This wireless communication uses frequency bands used in short-range communication, such as the 2.4 GHz band or the 5 GHz band.

[0067] The battery management system 60 employs either one-to-one communication or network communication depending on the number of nodes involved in the wireless communication performed by the monitoring device 30 and / or the controller 40. The number of nodes can vary depending on the resting state of the monitoring device 30 and / or the controller 40. When there are two nodes, the battery management system 60 employs one-to-one communication. When there are three or more nodes, the battery management system 60 employs network communication. An example of network communication is star communication, where wireless communication is performed between one node acting as the master node and the other nodes acting as slave nodes. Another example of network communication is chain communication, where multiple nodes are connected in series to perform wireless communication.

[0068] The battery management system 60 also includes sensors 70. Sensors 70 include: physical quantity detection sensors that detect physical quantities in each battery cell 22; and determination sensors. The physical quantity detection sensors include, for example, voltage sensors, temperature sensors, and current sensors.

[0069] The voltage sensor includes a detection line coupled to busbar 24. The voltage sensor detects the voltage (cell voltage) of each battery cell 22. The sensor determines whether the correct battery is attached.

[0070] Temperature sensors are selectively disposed in some of the battery cells 22 included in the battery stack 21. The temperature sensor detects the temperature (cell temperature) of a selected battery cell 22 as the temperature of the battery stack 21. For example, among the battery cells 22 included in a battery stack 21, the battery cell 22 expected to have the highest temperature, the battery cell 22 expected to have the lowest temperature, and the battery cell 22 expected to have an intermediate temperature are provided with temperature sensors. The number of temperature sensors used for a battery stack 21 is not particularly limited.

[0071] A current sensor is disposed in the battery stack 21. The current sensor detects the current (cell current) that typically flows through the series-connected battery cells 22 and the series-connected battery stack 21. In this embodiment, because all the battery stacks 21 are connected in series, only one current sensor is provided. However, the number of current sensors is not limited to this example.

[0072] <Monitoring Equipment>

[0073] First, monitoring device 30 will be described. Each monitoring device 30 has a common configuration. Monitoring device 30 includes a power supply circuit (PSC) 31, a multiplexer (MUX) 32, a monitoring IC (MIC) 33, a microcontroller (MC) 34, a wireless IC (WIC) 35, a front-end circuit (FE) 36, and an antenna (ANT) 37. Communication between the components within monitoring device 30 is performed via cables.

[0074] The power supply circuit 31 uses the voltage supplied from the battery stack 21 to generate operating power for other circuit elements included in the monitoring device 30. In this embodiment, the power supply circuit 31 includes power supply circuits 311, 312, and 313. Power supply circuit 311 uses the voltage supplied from the battery stack 21 to generate a predetermined voltage and supplies the generated voltage to the monitoring IC 33. Power supply circuit 312 uses the voltage generated by power supply circuit 311 to generate a predetermined voltage and supplies the generated voltage to the microcontroller 34. Power supply circuit 313 uses the voltage generated by power supply circuit 311 to generate a predetermined voltage and supplies the generated voltage to the wireless IC 35.

[0075] Multiplexer 32 is a selection circuit that selects one of the detection signals from at least some of the sensors 70 included in the battery pack 11 and outputs the selected signal. Multiplexer 32 selects (switches) the input according to the selection signal from monitoring IC 33 and outputs the input as a signal.

[0076] Monitoring IC 33 senses (acquires) battery information, such as cell voltage and cell temperature, and transmits this information to microcontroller 34. For example, monitoring IC 33 acquires the cell voltage directly from a voltage sensor and obtains information such as cell temperature via a multiplexer. Monitoring IC 33 acquires the cell voltage and determines which battery cell 22 corresponds to that voltage. That is, monitoring IC 33 acquires the cell voltage while performing cell determination. Cell current detected by a current sensor can be input to monitoring IC 33 or can be input to controller 40 via wired transmission.

[0077] The monitoring IC 33 can be referred to as the Cell Supervision Circuit (CSC). CSC is an abbreviation for Cell Supervision Circuit. The monitoring IC 33 performs fault diagnosis on the circuitry of the monitoring device 30, including the monitoring IC 33 itself. That is, the monitoring IC 33 sends battery monitoring information, including battery information and fault diagnosis information, to the microcontroller 34. The monitoring device 30 can store (hold) the acquired battery monitoring information in a memory such as the microcontroller 34. Upon receiving a request to retrieve data of battery monitoring information sent from the microcontroller 34, the monitoring IC 33 senses the battery information and sends battery monitoring information, including the battery information, to the microcontroller 34. In addition to the examples above, the battery monitoring information may also include information such as flue gas temperature, impedance, cell voltage balance, stack voltage, synchronization status with the controller 40, or the presence or absence of detection wiring abnormalities.

[0078] A microcontroller 34 is a microcomputer and includes a CPU as a processor, ROM and RAM as memory, input / output interfaces, and buses connecting these components. The CPU constructs multiple functional units by executing various programs stored in ROM while using the temporary storage function of RAM. ROM is an abbreviation for Read-Only Memory. RAM is an abbreviation for Random Access Memory.

[0079] Microcontroller 34 controls the timing of sensing and self-diagnostics performed by monitoring IC 33. Microcontroller 34 receives battery monitoring information from monitoring IC 33 and transmits it to wireless IC 35. Microcontroller 34 sends data requesting battery monitoring information to monitoring IC 33. For example, upon receiving data requesting battery monitoring information from wireless IC 35, microcontroller 34 can send the request data to monitoring IC 33. Microcontroller 34 can autonomously request battery monitoring information from monitoring IC 33. For example, microcontroller 34 can cyclically request battery monitoring information from monitoring IC 33.

[0080] The wireless IC 35 includes RF circuitry and a microcontroller (not shown) for wirelessly transmitting and receiving data. The microcontroller of the wireless IC 35 includes memory. The wireless IC 35 has a transmission function that modulates transmitted data and oscillates at the frequency of an RF signal. The wireless IC 35 has a reception function that demodulates received data. RF is an abbreviation for radio frequency.

[0081] The wireless IC 35 modulates data including battery monitoring information transmitted from the microcontroller 34 and transmits the modulated data to another node, such as the controller 40, via the front-end circuitry 36 and antenna 37. The wireless IC 35 adds data necessary for wireless communication, such as communication control information, to the transmitted data including the battery monitoring information, and then transmits the data. Data necessary for wireless communication includes, for example, identifiers (IDs) and error detection codes. For example, the wireless IC 35 controls the data size, communication format, schedule, and error detection in wireless communication with another node.

[0082] The wireless IC 35 receives data transmitted from another node via antenna 37 and front-end circuitry 36, and then demodulates the data. For example, upon receiving data including a request to transmit battery monitoring information, the wireless IC 35 responds by transmitting data including battery monitoring information to the other node. In addition to the battery monitoring information described above, the monitoring device 30 may also transmit battery traceability information and / or manufacturing history information to the other node. Battery traceability information includes, for example, the number of charge / discharge cycles, the number of failures, and the total charge / discharge time. Manufacturing history information includes, for example, the manufacturing date, location, manufacturer, serial number, and manufacturing number. The manufacturing history information is stored in a memory included in the monitoring device 30. The monitoring device 30 may transmit battery traceability information and / or manufacturing history information to the other node in place of the aforementioned battery monitoring information.

[0083] The front-end circuitry 36 includes a matching circuit for impedance matching between the wireless IC 35 and the antenna 37, and a filtering circuit for removing unwanted frequency components.

[0084] Antenna 37 converts electrical signals into radio waves and transmits the radio waves into space. Antenna 37 receives radio waves propagating in space and converts the radio waves back into electrical signals.

[0085] <Controller>

[0086] Next, we will refer to Figure 4 The controller 40 is described. The controller 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 microcontroller (MMC) 45, and a sub-microcontroller (SMC) 46. Communication between the components within the controller 40 is performed via cables.

[0087] Power supply circuit 41 uses the voltage supplied from battery (BAT) 15 to generate operating power for other circuit elements included in controller 40. Battery 15 is a DC voltage source installed on vehicle 10 and is different from battery pack 11. Battery 15 provides power to auxiliary equipment of vehicle 10 and can therefore be referred to as auxiliary battery. In this embodiment, power supply circuit 41 includes power supply circuits 411 and 412. Power supply circuit 411 uses the voltage supplied from battery 15 to generate a predetermined voltage and supplies the generated voltage to main microcontroller 45 and sub-microcontroller 46. For simplicity of the drawings, the electrical connection between power supply circuit 411 and sub-microcontroller 46 is omitted. Power supply circuit 412 uses the voltage generated by power supply circuit 411 to generate a predetermined voltage and supplies the predetermined voltage to wireless IC 44.

[0088] Antenna 42 converts electrical signals into radio waves and transmits the radio waves into space. Antenna 42 receives radio waves propagating in space and converts the radio waves back into electrical signals.

[0089] The front-end circuit 43 includes a matching circuit for impedance matching between the wireless IC 44 and the antenna 42, and a filtering circuit for removing unwanted frequency components.

[0090] Wireless IC 44 includes RF circuitry and a microcontroller (not shown) for wirelessly transmitting and receiving data. Wireless IC 44, like Wireless IC 35, has both transmitting and receiving functions. Wireless IC 44 receives data transmitted from monitoring device 30 via antenna 42 and front-end circuitry 43, and then demodulates the data. Wireless IC 44 transmits data including battery monitoring information to main microcontroller 45. Wireless IC 44 receives and modulates data transmitted from main microcontroller 45, and transmits the data to monitoring device 30 via front-end circuitry 43 and antenna 42. Wireless IC 44 adds data necessary for wireless communication, such as communication control information, to the transmitted data and transmits that data. Data necessary for wireless communication includes, for example, identifiers (IDs) and error detection codes. Wireless IC 44 controls the data size, communication format, schedule, and error detection in wireless communication with other nodes.

[0091] The main microcontroller 45 is a microcomputer including a CPU, ROM, RAM, input / output interfaces, and buses connecting these components. The ROM stores various programs to be executed by the CPU. The main microcontroller 45 generates commands requesting the monitoring device 30 to perform a predetermined process and sends transmission data including the command to the wireless IC 44. The main microcontroller 45 generates commands, for example, to request the transmission of battery monitoring information. The main microcontroller 45 can generate commands for not only requesting the acquisition of battery monitoring information but also requesting the transmission of battery monitoring information. The requests described herein can be referred to as instructions.

[0092] The main microcontroller 45 receives data including battery monitoring information transmitted from the wireless IC 44 and executes a predetermined process based on the battery monitoring information. In this embodiment, the main microcontroller 45 acquires the cell current from a current sensor and executes a predetermined process based on the battery monitoring information and the acquired cell current. For example, the main microcontroller 45 executes the process of sending the acquired battery monitoring information to the ECU 14. The main microcontroller 45 can calculate at least one of the internal impedance, open-circuit voltage (OCV), state of charge (SOC), and state of equilibrium (SOH) of the battery cell 22 based on the battery monitoring information and send information including the calculated data to the ECU 14. OCV is an abbreviation for open-circuit voltage.

[0093] The main microcontroller 45 performs an estimation process based on, for example, cell voltage and cell current to estimate the internal impedance and open-circuit voltage of the battery cell 22. The open-circuit voltage is the cell voltage corresponding to the state of charge (SOC) of the battery cell 22. The open-circuit voltage is the cell voltage when no current flows. The open-circuit voltage and cell voltage acquired by the monitoring device 30 have a voltage drop difference based on the internal impedance and cell current. The internal impedance varies with cell temperature. The lower the cell temperature, the higher the internal impedance value. The main microcontroller 45 performs the estimation process to estimate the internal impedance and open-circuit voltage of the battery cell 22, also taking into account, for example, cell temperature.

[0094] The main microcontroller 45 can perform a voltage balancing process for equalizing the battery cell 22 based on battery monitoring information. The main microcontroller 45 can acquire the IG signal from the vehicle 10 and perform the above process according to the driving state of the vehicle 10. The main microcontroller 45 can perform a process to detect abnormalities in the battery cell 22 or the circuit based on battery monitoring information, and can send the abnormality detection information to the ECU 14.

[0095] The sub-microcontroller 46 is a microcomputer that includes a CPU, ROM, RAM, input / output interfaces, and buses connecting these components. The ROM stores various programs to be executed by the CPU. The sub-microcontroller 46 performs monitoring processes within the controller 40. For example, the sub-microcontroller 46 can monitor data between the wireless IC 44 and the main microcontroller 45. The sub-microcontroller 46 can monitor the status of the main microcontroller 45. The sub-microcontroller 46 can monitor the status of the wireless IC 44.

[0096] <Communication during runtime>

[0097] According to this embodiment, the battery management system 60 performs star network communication while the assembled battery 20 is in operation (where power is supplied from the assembled battery 20 to an onboard system such as the MG 13 via a system main relay (SMR) (not shown). That is, the controller 40 performs wireless communication with each monitoring device 30 via a separately established communication connection. For convenience, the wireless communication between one monitoring device 30 and the controller 40 will be described below. The controller 40 performs a similar process with all monitoring devices 30.

[0098] First, refer to Figure 5 and Figure 6 The connection process for establishing a separate communication connection between each monitoring device 30 and controller 40 will be described. Figure 5 This is a diagram illustrating the communication sequence between the monitoring device 30 and the controller 40. This communication sequence can also be referred to as a communication flow. Figure 6 An example of the connection process is shown. Figure 5 and Figure 6 In this context, controller 40 is referred to as ECU 40.

[0099] like Figure 5 As shown, a connection process (S10) is performed between the controller 40 and each monitoring device 30 to establish a communication connection with each monitoring device 30 individually. In the communication connection, the controller 40 acts as the communication master and each monitoring device 30 acts as the communication slave. Since the controller 40 and each monitoring device 30 communicate according to the BLE communication protocol, the connection process (S10) includes a connection establishment process (S11) and a pairing process (S12), as follows. Figure 6 As shown. BLE is an abbreviation for Bluetooth Low Energy. Bluetooth is a registered trademark. However, communication between the controller 40 and each monitoring device 30 can be performed according to communication protocols other than the BLE communication protocol.

[0100] During the connection establishment process (S11), the controller 40 performs a scanning operation (S111), and the monitoring device 30 performs an announcement operation (S112). The scanning operation may start earlier than, approximately at the same time as, or later than the announcement operation.

[0101] To notify controller 40 of the presence of monitoring device 30, wireless IC 35 of monitoring device 30 performs an announcement operation to send an announcement packet (ADV_PKT) to wireless IC 44 of controller 40. The announcement packet includes the ID information of monitoring device 30 and the ID information of controller 40.

[0102] When a notification packet is detected through a scanning operation (i.e., monitoring device 30 is detected), the controller 40 sends a connection request (CONNECT_REQ) to the detected monitoring device 30 (S113).

[0103] When monitoring device 30 receives a connection request, it establishes a connection between monitoring device 30 and controller 40. Once the connection is established, monitoring device 30 stops sending notification packets. Monitoring device 30 continuously sends notification packets until a connection is established.

[0104] When the connection establishment process ends, a pairing process (S12) is then executed. The pairing process is used to perform encrypted data communication. The pairing process includes a unique information exchange process (S121). During the exchange, unique information held by the two devices (e.g., encryption keys or information used to generate encryption keys) is exchanged and stored in each device's memory. After executing step S121, encryption using the exchanged unique information becomes possible.

[0105] Although an example has been described in which the controller 40 performs a scanning operation and the monitoring device 30 performs an announcement operation, the present invention is not limited to this example. The monitoring device 30 may perform a scanning operation, and the controller 40 may perform an announcement operation.

[0106] Next, refer to Figure 5 and Figure 7 This will describe the periodic communication process performed between the monitoring device 30 and the controller 40 during the operation of the assembled battery 20. Figure 7 An example of a periodic communication process is shown. In Figure 7 In the diagram, monitoring IC 33 is shown as MIC 33, wireless IC 35 is shown as WIC 35, and controller 40 is shown as ECU 40.

[0107] When the above connection process is completed, the monitoring device 30 and the controller 40 perform a periodic communication process (S20). During this periodic communication process, the controller 40 and the monitoring device 30 periodically (cyclically) perform data communication. For example, in data communication, such as... Figure 7 As shown, the controller 40 sends request data to the monitoring device 30, which has completed the connection process with the controller 40 (S21). As an example, the controller 40 sends request data including a request to acquire battery monitoring information and a request to send the information.

[0108] Upon receiving the requested data, the wireless IC 35 of the monitoring device 30 sends a request to the monitoring IC 33 to obtain battery monitoring information, i.e., an acquisition command (S22). In this embodiment, the wireless IC 35 sends the acquisition request to the monitoring IC 33 via the microcontroller 34.

[0109] Upon receiving an acquisition request, monitoring IC 33 performs sensing (S23). Monitoring IC 33 performs sensing and acquires battery information for each battery cell 22. Monitoring IC 33 also performs circuit fault diagnosis.

[0110] Next, the monitoring IC 33 sends the acquired battery monitoring information to the wireless IC 35 (S24). In this embodiment, the monitoring IC 33 sends battery monitoring information, including fault diagnosis results and battery information. The monitoring IC 33 sends the battery monitoring information to the wireless IC 35 via the microcontroller 34.

[0111] When the wireless IC 35 receives battery monitoring information from the monitoring IC 33, the wireless IC 35 sends transmission data, i.e., response data, including the battery monitoring information to the controller 40 (S25). The controller 40 receives the response data (S26). The controller 40 periodically performs data communication with the monitoring device 30 (with which a connection has been established).

[0112] Based on the received response data, i.e., battery monitoring information, the controller 40 executes a predetermined process (S30). For example, the controller 40 executes the process of sending the acquired battery monitoring information to the ECU 14, the process of instructing the execution of a balancing process to equalize the voltage of the battery cell 22, and the process of detecting abnormalities in the battery cell 22, as described above.

[0113] Although an example has been described of the monitoring device 30 acquiring battery monitoring information based on an acquisition request from the controller 40, the present invention is not limited to this example. The monitoring device 30 can autonomously acquire battery monitoring information and send the battery monitoring information to the controller 40 based on a transmission request from the controller 40. Therefore, the processes of steps S22 to S24 in response to the acquisition request become unnecessary.

[0114] Communication during non-running mode

[0115] The battery management system 60 according to this embodiment maintains communication between the controller 40 and the monitoring device 30 even when the assembled battery 20 is in a non-operating state, so that communication can be quickly initiated between the controller 40 and the monitoring device 30 when switching from the non-operating state of the assembled battery 20 to the operating state. The non-operating state is, for example, a state in which the SMR is turned off by turning off the ignition switch and there is no need to supply power from the assembled battery 20 to the vehicle system (e.g., MG 13) via the SMR. Figure 8 (a) illustrates the communication mode (i.e., star network) during the operation of the assembled battery 20, where the controller 40 acts as the communication master and communicates independently with the monitoring devices 30, which act as communication slaves. If this communication mode is maintained even in the non-operational state of the assembled battery 20, the power consumption of the controller 40 becomes greater than the power consumption of each monitoring device 30. The main reason is that the controller 40 needs to communicate with multiple monitoring devices 30, and the communication master typically performs functions such as communication schedule management, which are generally more demanding than the functional load of the communication slaves. Even in the non-operational state of the assembled battery 20, the assembled battery 20 does not need to supply power to devices (e.g., monitoring devices 30 directly connected to the assembled battery 20) via SMR.

[0116] Therefore, according to this embodiment, the battery management system 60 switches the communication mode to a different mode than the operating mode when the assembled battery 20 is in a non-operating state. Thus, communication between the controller 40 and the monitoring device 30 can be maintained, while the power consumption of the controller 40 is reduced. The communication mode between the controller 40 and the monitoring device 30 in the non-operating state of the assembled battery 20 will be described in detail below.

[0117] Figure 8 (b) is a diagram illustrating an example of the communication network of the assembled battery 20 in a non-operational state. Figure 8As shown in (b), in the non-operating state of the assembled battery 20, the controller 40 acts as the communication master device for one of the monitoring devices 30_1, 30_2, and 30_3. One of the monitoring devices 30_1, 30_2, and 30_3 then sequentially acts as the communication master device for the other of the monitoring devices 30_1, 30_2, and 30_3. That is, in the non-operating state of the assembled battery 20, the controller 40 establishes sequential connections with the monitoring devices 30_1, 30_2, and 30_3, and the communication mode between the controller 40 and the monitoring devices 30_1, 30_2, and 30_3 is a chain network. By adopting this communication mode in the non-operating state of the assembled battery 20, the power consumption of devices 40, 30_1, 30_2, and 30_3 can be balanced.

[0118] exist Figure 8 In the example shown in (b), controller 40 acts not only as the communication master device for monitoring device 30_1, but also as the communication slave device for monitoring device 30_3. However, one of the communication paths between controller 40 and monitoring device 30_1, as well as between monitoring devices 30_1, 30_2, and 30_3, can be omitted. This is because, even without forming a communication path, controller 40 and all monitoring devices 30_1, 30_2, and 30_3 can still join the communication network. Although in Figure 8 (b) The number of monitoring devices 30 is three, but the number of monitoring devices 30 is not limited to this and can be two, four, or more. When the number of monitoring devices 30 is relatively large, Figure 8 (b) The number of communication networks shown can be more than one. In this case, the controller 40 can act as the communication master for two or more monitoring devices 30.

[0119] Next, refer to Figure 9 The flowchart will describe the process of changing the communication network executed by each of the controller 40 and monitoring devices 30_1, 30_2, and 30_3 when the assembled battery 20 switches from an operating state to a non-operating state and from a non-operating state to an operating state.

[0120] In step S40, the controller 40 detects the ignition switch being turned off as a trigger for switching from the operating state to the non-operating state of the battery assembly 20. However, the switching from the operating state to the non-operating state of the battery assembly 20 can also be detected by using, for example, the fact that the vehicle has stopped, the driver has exited the vehicle, or the fact that each door of the vehicle is locked. When the ignition switch is detected to be off, the controller 40 notifies each of the monitoring devices 30_1, 30_2, and 30_3 that the ignition switch is off. In other words, each of the monitoring devices 30_1, 30_2, and 30_3 is notified that, for the non-operating state of the battery assembly 20, the communication network mode needs to be changed to a chain network.

[0121] Since controller 40 and monitoring devices 30_1, 30_2, and 30_3 all act not only as communication masters but also as communication slaves to other devices 40_1, 30_2, and 30_3, they all perform connection acceptance operations (scanning operations) and connection request operations (announcing operations). More specifically, controller 40 and monitoring devices 30_1, 30_2, and 30_3 perform connection acceptance and connection request operations at different times, such as... Figure 9 The flowchart is shown. A combination of devices 40, 30_1, 30_2, and 30_3 acting as communication masters and slave devices 40, 30_1, 30_2, and 30_3 can be pre-configured. However, these combinations can be determined by one of the controller 40 and monitoring devices 30_1, 30_2, and 30_3 when the ignition switch is detected to be off, and then one device can notify the other devices 40, 30_1, 30_2, and 30_3 of these combinations.

[0122] For example, in Figure 9 In the example shown in the flowchart, monitoring device 30_1 performs a connection acceptance operation in step S41 to act as the communication master device of monitoring device 30_2, and in step S42, monitoring device 30_2 performs a connection request operation to act as the communication slave device of monitoring device 30_1. In step S43, monitoring device 30_3 performs a connection acceptance operation to act as the communication master device of controller 40, and in step S44, controller 40 performs a connection request operation to act as the communication slave device of monitoring device 30_3. In step S45, connection establishment operations are performed between monitoring device 30_1 and monitoring device 30_2, and between monitoring device 30_3 and controller 40. In the connection establishment operation, the communication master device detects the advertisement packet sent from the communication slave device, sends a connection request (CONNECT_REQ) to the communication slave device, and further, the communication master device and the communication slave device exchange unique information.

[0123] In the star network formed during the operation of the assembled battery 20, a communication connection has been established between the controller 40, acting as the communication master, and the monitoring device 30_3, acting as the communication slave. This established communication connection can be used to switch the roles of communication master and communication slave between the controller 40 and the monitoring device 30_3, instead of performing the connection acceptance operation in step S43 and the connection request operation in step S44. This role switching can be performed if it is easier and faster to complete the switching between the communication master and communication slave roles using the established communication connection than to establish a new communication connection through scanning and notification operations.

[0124] exist Figure 9 In the example shown in the flowchart, after the connection establishment operation in step S45 is completed, controller 40 performs a connection acceptance operation in step S46 to act as the communication master device of monitoring device 30_1, and monitoring device 30_1 performs a connection request operation in step S47 to act as the communication slave device of controller 40. Monitoring device 30_2 performs a connection acceptance operation in step S48 to act as the communication master device of monitoring device 30_3, and monitoring device 30_3 performs a connection request operation in step S49 to act as the communication slave device of monitoring device 30_2. In step S50, connection establishment operations are performed between controller 40 and monitoring device 30_1, and between monitoring device 30_2 and monitoring device 30_3.

[0125] In the star network formed during the operation of the assembled battery 20, a communication connection has been established between the controller 40, which is the communication master device, and the monitoring device 30_1, which is the communication slave device. Since the established communication connection can be directly used as a communication connection between the controller 40 and the monitoring device 30_1, the connection acceptance operation in step S46 and the connection request operation in step S47 can be omitted.

[0126] Figure 9 The flowchart illustrates that connection establishment operations are first performed between monitoring devices 30_1 and 30_2, and between monitoring device 30_3 and controller 40, followed by connection establishment operations between controller 40 and monitoring device 30_1, and between monitoring devices 30_2 and 30_3. However, in practice, controller 40 and monitoring devices 30_1, 30_2, and 30_3 individually and cyclically repeat connection acceptance and connection request operations. Then, when the communication slave and communication master devices to be paired have sent and received announcement packets and connection requests in response to the announcement packets, connection establishment operations are performed between them. When controller 40 and monitoring devices 30_1, 30_2, and 30_3 first complete the connection establishment operation as communication masters, controller 40 and monitoring devices 30_1, 30_2, and 30_3 stop the connection acceptance operation and only continue the connection request operation until the connection establishment operation as communication slave devices is completed. On the other hand, when the controller 40 and the monitoring devices 30_1, 30_2, and 30_3 first complete the connection establishment operation as communication slave devices, the controller 40 and the monitoring devices 30_1, 30_2, and 30_3 stop the connection request operation and only continue the connection acceptance operation until they complete the connection establishment operation as communication master devices.

[0127] The communication connection during the operation of the assembled battery 20 is disconnected no later than the start of periodic communication following the detection of the ignition switch being turned off, wherein the controller 40 acts as the communication master and each of the monitoring devices 30_2 and 30_3 acts as the communication slave.

[0128] Figure 8 (b) The chain network shown is formed by the above-described process executed by controller 40 and monitoring devices 30_1, 30_2, and 30_3. Figure 9 In step S51 of the flowchart, periodic communication is performed between the communication master device and the communication slave device in the formed chain network. However, during periodic communication, since the assembled battery 20 is in a non-operating state, it is not necessary to send the aforementioned battery monitoring information. The periodic communication is mainly performed to maintain the formed chain network.

[0129] In step S52, the controller 40 detects that the ignition switch is turned on as a trigger for switching from the non-operating state to the operating state of the assembled battery 20. Alternatively, for example, the trigger for switching from the non-operating state to the operating state of the assembled battery 20 can be detected by the fact that a user holding the smart key approaches the vehicle, the fact that the vehicle door is unlocked, or the fact that the driver is sitting in the driver's seat. Upon detecting that the ignition switch is turned on, the controller 40 notifies each of the monitoring devices 30_1, 30_2, and 30_3 via a chain network that the ignition switch is turned on. In other words, each of the monitoring devices 30_1, 30_2, and 30_3 is notified that the communication network mode needs to be changed to a star network for the operating state of the assembled battery 20.

[0130] Controller 40 acts as the communication master device for each of monitoring devices 30_1, 30_2, and 30_3, and each of monitoring devices 30_1, 30_2, and 30_3 acts as a communication slave device for controller 40. Therefore, controller 40 and monitoring devices 30_1, 30_2, and 30_3 perform connection acceptance operations (scanning operations) and connection request operations (announcing operations). More specifically, controller 40 performs the connection acceptance operation in step S53, and monitoring devices 30_2 and 30_3 perform connection request operations in steps S54 and S55. In step S56, a connection establishment operation is performed between controller 40 and each of monitoring devices 30_1, 30_2, and 30_3.

[0131] Since monitoring device 30_1 has already established a communication connection with controller 40, which acts as the communication master, monitoring device 30_1 does not repeat the connection request operation. As described above, in the non-operating state of assembled battery 20, controller 40 maintains a communication connection with monitoring device 30_1 while acting as the communication master. Therefore, a star network can be formed more quickly in the operating state of assembled battery 20, and communication with each of monitoring devices 30_1, 30_2, and 30_3 can be initiated.

[0132] In the chain network formed during the non-operational state of the assembled battery 20, a communication connection is established between the controller 40 and the monitoring device 30_3, with the controller 40 acting as a communication slave and the monitoring device 30_3 as a communication master. This established communication connection can be used to switch the roles of communication master and communication slave between the controller 40 and the monitoring device 30_3, instead of performing connection acceptance and connection request operations. This role switching can be performed if it is easier and faster to complete than establishing a new communication connection through scanning and announcement operations.

[0133] In the non-operational state of the assembled battery 20, the communication connection between the controller 40 and each of the monitoring devices 30_1, 30_2, and 30_3 forming a chain network is disconnected no later than when periodic communication begins after the detection of the ignition switch being turned on is sent to each of the monitoring devices 30_1, 30_2, and 30_3.

[0134] (Second Embodiment)

[0135] Next, a battery management system 60 according to a second embodiment will be described with reference to the accompanying drawings. The battery management system 60 according to this embodiment is constructed similarly to the battery management system 60 according to the first embodiment. Therefore, a description of the structure of the battery management system 60 according to this embodiment will be omitted.

[0136] Similar to the first embodiment, when the assembled battery 20 is in a non-operating state, the battery management system 60 according to this embodiment switches the communication mode to a mode different from the operating mode. Therefore, communication between the controller 40 and the monitoring device 30 is maintained, while the power consumption of the controller 40 is reduced. However, unlike the first embodiment, the battery management system 60 according to this embodiment divides the master-slave pairs among the controller 40 and the monitoring devices 30_1, 30_2, and 30_3 into multiple groups. The divided groups perform periodic communication sequentially in a time-sharing manner. That is, the communication group performing communication is selected from the groups and changes periodically. Figure 10In this setup, controller 40 and monitoring device 30_3 form one pair, and monitoring device 30_1 and monitoring device 30_2 form another pair. These device pairs belong to the same group and communicate with each other. In this way, multiple master-slave device pairs can belong to the same group.

[0137] In this way, the communication frequency between the controller 40 and each of the monitoring devices 30_1, 30_2, and 30_3 can be reduced, and the power consumption of each of the devices 40, 30_1, 30_2, and 30_3 can be further reduced.

[0138] Next, refer to Figure 11 The flowchart below will describe the processes performed by the controller 40 and monitoring devices 30_1, 30_2, and 30_3 in this embodiment.

[0139] Figure 11 The process of steps S60 to S64 in the flowchart is similar to Figure 9 The processes of steps S40 to S44 in the flowchart are the same. In step S65, connection establishment operations are performed between monitoring device 30_1 and monitoring device 30_2, and between monitoring device 30_3 and controller 40. The pair formed by monitoring device 30_1 acting as the communication master and monitoring device 30_2 acting as the communication slave, and the pair formed by monitoring device 30_3 acting as the communication master and controller 40 acting as the communication slave belong to group A.

[0140] Figure 11 The process of steps S66 to S69 in the flowchart is similar to Figure 9 The processes of steps S46 to S49 in the flowchart are the same. In step S70, connection establishment operations are performed between controller 40 and monitoring device 30_1, and between monitoring device 30_2 and monitoring device 30_3. The pair formed by controller 40 acting as the communication master device and monitoring device 30_1 acting as the communication slave device, and the pair formed by monitoring device 30_2 acting as the communication master device and monitoring device 30_3 acting as the communication slave device, belong to group B.

[0141] exist Figure 11In the flowchart, for convenience, pairs belonging to group A—namely, the pair formed by monitoring device 30_1 acting as the communication master and monitoring device 30_2 acting as the communication slave, and the pair formed by monitoring device 30_3 acting as the communication master and controller 40 acting as the communication slave—first perform the connection establishment operation. Then, pairs belonging to group B—namely, the pair formed by controller 40 acting as the communication master and monitoring device 30_1 acting as the communication slave, and the pair formed by monitoring device 30_2 acting as the communication master and monitoring device 30_3 acting as the communication slave—perform the connection establishment operation. However, as described in the first embodiment, in practice, controller 40 and monitoring devices 30_1, 30_2, and 30_3 individually and cyclically repeat the connection acceptance operation and connection request operation. Then, when the communication slave and communication master to be paired have sent and received notification packets and connection requests in response to the notification packets, a connection establishment operation is performed between them. When all connection establishment operations are completed, pairs belonging to group A perform synchronous communication, and pairs belonging to group B perform synchronous communication at a different time than those in group A. That is, in the periodic communication in step S71, the communication between the master-slave pair belonging to group A and the communication between the master-slave pair belonging to group B are executed alternately.

[0142] The master-slave pairs can be pre-configured to belong to a specific group. One of the controller 40 or monitoring devices 30_1, 30_2, and 30_3 can group the devices based on the charging level of the battery stack 21 monitored by the monitoring devices 30_1, 30_2, and 30_3. When the monitoring devices 30_1, 30_2, and 30_3 group the devices based on the charging level of the battery stack 21, pairs where the master communication device is a monitoring device 30 (high-charging monitoring device) monitoring a battery stack 21 with a relatively high charge level can belong to the same group (referred to as the "high-charging group"), and pairs where the master communication device is a monitoring device 30 (low-charging monitoring device) monitoring a battery stack 21 with a relatively low charge level can belong to the same group (referred to as the "low-charging group"). Furthermore, one of the controller 40 or monitoring devices 30_1, 30_2, and 30_3 can manage the cyclical changes of the communication groups, such that during periodic communication, the communication frequency in the high-charging group becomes higher than the communication frequency in the low-charging group.

[0143] Compared to communication slave devices, the power consumed in communication with communication partners is higher in communication master devices. Therefore, this increase in the communication frequency of the communication master device can lead to a balance (i.e., equalization) of the charge quantity in the battery stack 21.

[0144] To increase the communication frequency in the high-charge group, for example, one of the controller 40 or monitoring devices 30_1, 30_2, 30_3 can manage the cyclical changes of the communication group, making the communication cycle of the high-charge group longer than that of the low-charge group.

[0145] Alternatively, for example, one of the controller 40 or monitoring devices 30_1, 30_2, 30_3 can manage the cyclical changes of the communication groups, such that the frequency of selecting the high-charge group as the communication group becomes higher than the frequency of selecting the low-charge group as the communication group. Specifically, the cyclical changes of the communication groups can be managed such that the high-charge group is selected as the communication group more often than the low-charge group is selected as the communication group.

[0146] (Third Embodiment)

[0147] Next, a battery management system 60 according to a third embodiment will be described with reference to the accompanying drawings. The battery management system 60 according to this embodiment is constructed similarly to the battery management system 60 according to the first embodiment. Therefore, a description of the structure of the battery management system 60 according to this embodiment will be omitted.

[0148] Similar to the second embodiment, the battery management system 60 of this embodiment groups the master and slave devices among the controller 40 and monitoring devices 30_1, 30_2, and 30_3. The divided groups sequentially perform periodic communication in a time-sharing manner. In this embodiment, as... Figure 12 As shown, the number of master-slave pairs for communication in each group is less than the number of master-slave pairs in the second embodiment. As a result, the power consumed by the controller 40 in communicating with each of the monitoring devices 30_1, 30_2, and 30_3 can be further reduced.

[0149] Next, refer to Figure 13 The flowchart below will describe the process executed by each of the controller 40 and monitoring devices 30_1, 30_2, and 30_3 in this embodiment.

[0150] Figure 13 The process of step S80 in the flowchart is similar to Figure 9 The process is described in step S40 of the flowchart. In step S81, monitoring device 30_1 performs a connection acceptance operation to act as the communication master device of monitoring device 30_2. In step S82, monitoring device 30_2 performs a connection request operation to act as the communication slave device of monitoring device 30_1. In step S83, a connection establishment operation is performed between monitoring device 30_1 and monitoring device 30_2. At this time, the pair formed by monitoring device 30_1 acting as the communication master device and monitoring device 30_2 acting as the communication slave device belongs to group C.

[0151] In step S84, monitoring device 30_2 performs a connection acceptance operation to act as the communication master device of monitoring device 30_3. In step S85, monitoring device 30_3 performs a connection request operation to act as the communication slave device of monitoring device 30_2. In step S86, a connection establishment operation is performed between monitoring device 30_2 and monitoring device 30_3. At this time, the pair formed by monitoring device 30_2 acting as the communication master device and monitoring device 30_3 acting as the communication slave device belongs to group D.

[0152] In step S87, the monitoring device 30_3 performs a connection acceptance operation to act as the communication master device of the controller 40. In step S88, the controller 40 performs a connection request operation to act as the communication slave device of the monitoring device 30_3. The connection acceptance operation and the connection request operation can be replaced by a process of switching the function of the communication master device and the function of the communication slave device. In step S89, a connection establishment operation is performed between the monitoring device 30_3 and the controller 40. At this time, the pair formed by the monitoring device 30_3 acting as the communication master device and the controller 40 acting as the communication slave device belongs to group E.

[0153] A communication connection has been established between a controller 40, acting as the communication master, and a monitoring device 30_1, acting as the communication slave. This pair belongs to group F. As described above, the order in which the connection establishment operations performed by the controller 40 and the monitoring devices 30_1, 30_2, and 30_3 are performed is not limited to... Figure 13 The flowchart shows an example.

[0154] In the periodic communication in step S90, the master-slave pairs belonging to groups C to F perform communication in a predetermined order. At this time, similar to the second embodiment, one of the controller 40 or monitoring devices 30_1, 30_2, and 30_3 can manage the periodic changes of the communication groups, such that in the periodic communication, the communication frequency in the pair where the communication master device is monitoring the battery stack 21 with a relatively high charge becomes higher than the communication frequency in the pair where the communication master device is monitoring the battery stack 21 with a low charge.

[0155] (Other embodiments)

[0156] The disclosure in this specification, drawings, etc., is not limited to exemplary embodiments. This disclosure includes embodiments and variations thereof as shown by those skilled in the art. For example, this disclosure is not limited to the combinations of components and / or elements shown in the embodiments. This disclosure is feasible through various combinations. This disclosure may have additional portions that can be added to embodiments. This disclosure covers embodiments in which some components and / or elements are omitted. This disclosure covers substitutions or combinations of components and / or elements between one embodiment and another. The scope of the disclosed technology is not limited to the description of the embodiments. Several technical scopes disclosed are indicated by the description of the claims and should be further understood to include all modifications within the meaning and scope equivalent to the description of the claims.

[0157] When an element or layer is described as “on,” “coupled,” “connected,” or “combined,” it can be directly on, coupled to, connected to, or combined with another element or layer, or further, there may be intermediate elements or layers. In contrast, when an element is described as “directly on,” “directly coupled to,” “directly connected to,” or “directly combined with” another element or layer, there are no intermediate elements or layers. Other terms used to describe relationships between elements should be interpreted in a similar manner (e.g., “between” and “directly between,” “adjacent” and “directly adjacent,” etc.). As used herein, the term “and / or” includes any and all combinations relating to one or more of the related listed items. For example, the terms A and / or B include only A, only B, or both A and B.

[0158] Spatially relative terms such as “inside,” “outside,” “back,” “below,” “low,” “above,” and “high” are used herein to facilitate the description of the relationship between one element or feature and another, as shown in the figures. In addition to the orientations depicted in the figures, spatially relative terms are intended to encompass different orientations of the device in use or operation. For example, when the device in the figures is flipped, an element described as “below” or “directly below” other elements or features is oriented as “above” other elements or features. Thus, the term “below” can include both above and below. The device may be oriented in another direction (rotated 90 degrees or any other direction), and the spatially relative terms used herein are interpreted accordingly.

[0159] The apparatus, systems, and methods described in this disclosure can be implemented by a dedicated computer forming a processor programmed to perform one or more specific functions embodied in a computer program. Alternatively, the apparatus and methods described in this disclosure can be implemented entirely by dedicated logic hardware circuitry. Alternatively, the apparatus and methods described in this disclosure can be implemented by one or more dedicated computers formed by a combination of a processor executing a computer program and one or more hardware logic circuits. The computer program can be stored as instructions executable by the computer on a computer-readable, non-transitory tangible recording medium.

[0160] For example, an example of a monitoring device 30 including a microcontroller 34 has been described, but this disclosure is not limited thereto. A battery management system 60 in which the monitoring device 30 does not include the microcontroller 34 can be employed. In this configuration, a wireless IC 35 sends data to and receives data from a monitoring IC 33. The wireless IC 35 can perform sensing and self-diagnostic timing control by the monitoring IC 33, or the main microcontroller 45 of the controller 40 can perform sensing and timing control.

[0161] An example of arranging a monitoring device 30 for each of the respective battery stacks 21 has been shown, but this disclosure is not limited thereto. For example, one monitoring device 30 may be provided for multiple battery stacks 21. Multiple monitoring devices 30 may be arranged for one battery stack 21.

[0162] Although an example of a battery pack 11 including a controller 40 has been described, the invention is not limited thereto. The battery pack 11 may include multiple controllers 40. An example of a monitoring device 30 including a monitoring IC 33 has been described, but the present disclosure is not limited thereto. The monitoring device 30 may include multiple monitoring ICs 33. In this case, a wireless IC 35 may be provided for each monitoring IC 33, or a single wireless IC 35 may be provided for multiple monitoring ICs 33.

[0163] The arrangement and number of the battery stack 21 and battery cells 22 constituting the assembled battery 20 are not limited to the examples described above. The arrangement of the monitoring device 30 and / or controller 40 in the battery pack 11 is also not limited to the examples described above.

[0164] In each of the above embodiments, the monitoring system of this disclosure is embodied as a battery management system 60 configured to monitor each battery stack 21 of the assembled battery 20. However, the monitoring system according to this disclosure can also be used to monitor targets other than each battery stack 21 of the assembled battery 20. For example, the monitoring system according to this disclosure can be embodied as a system that wirelessly communicates with pneumatic sensor units integrated in each wheel of a vehicle to monitor each pneumatic sensor unit. In this case, each monitoring device is provided on each wheel, and at least one controller is provided inside the vehicle.

Claims

1. A monitoring system, comprising: A monitoring device is installed in the monitored device and monitors the monitored device. as well as A controller configured to wirelessly communicate with the monitoring device to obtain monitoring information of the monitored device from the monitoring device, wherein... The monitored device can switch between operating and non-operating states. In the operating state of the monitored device, the controller and the monitoring device establish respective connections, wherein the controller, acting as a communication master, performs wireless communication with each of the monitoring devices, which acts as a communication slave. In the non-operational state of the monitored device, the controller and the monitoring device maintain communication by establishing a sequential connection, wherein: The controller, acting as a communication master device, performs wireless communication with one of the monitoring devices, acting as a communication slave device; and One of the monitoring devices acting as a communication master device sequentially performs wireless communication with another monitoring device acting as a communication slave device.

2. The monitoring system according to claim 1, wherein The controller operates by being powered by a power supply device, which is different from the power supply device that powers the monitoring equipment.

3. The monitoring system according to claim 1 or 2, wherein... In response to an instruction to switch from the operating state to the non-operating state of the monitored device, the controller continues to act as the communication master for one of the monitored devices by maintaining one of the connections.

4. The monitoring system according to claim 1 or 2, wherein In the non-operational state of the monitored device, the controller acts as the communication master for one of the monitoring devices and as the communication slave for another of the monitoring devices acting as the communication master.

5. The monitoring system according to claim 4, wherein In response to an instruction to switch from the operating state to the non-operating state of the monitored device, the controller becomes the communication slave device by switching roles between the controller acting as the communication master device and the monitoring device acting as the communication slave device in one of the various connections.

6. The monitoring system according to claim 1 or 2, wherein In response to an instruction to switch from the non-operating state to the operating state of the monitored device, the controller and the monitoring device remain as part of a sequential connection between the controller acting as the communication master and one of the monitoring devices acting as the communication slave, and establish respective connections between the controller and each of the remaining monitoring devices in the monitoring device.

7. The monitoring system according to claim 4, wherein In response to an instruction to switch from the non-operating state to the operating state of the monitored device, the controller becomes the communication master device by switching roles between the controller acting as the communication slave device and the monitoring device acting as the communication master device in the sequential connection.

8. The monitoring system according to claim 6, wherein Instructions for switching from the non-operating state to the operating state of the monitored device are sent directly from the controller to each of the monitoring devices, or indirectly from the controller to each of the monitoring devices via the sequential connection maintained in the non-operating state of the monitored device.

9. The monitoring system according to claim 1 or 2, wherein In the non-operational state of the monitored device, the master-slave pairs formed by the communication master and slave devices in the controller and the monitoring device belong to any one of the groups. The communication group in which communication is performed is selected from the group and changes cyclically within the group.

10. The monitoring system according to claim 9, wherein Each group in the group includes two or more master-slave pairs in the master-slave pair.

11. The monitoring system according to claim 9, wherein: The monitored device is an assembled battery including a battery stack; The monitoring devices are configured to monitor the battery stacks separately, and each device is powered by a corresponding battery stack from the battery stacks to be monitored; and When the monitoring device detects an imbalance in the charging amount of the battery stack: The monitoring equipment includes high-charge monitoring equipment for monitoring battery stacks with relatively high charge levels and low-charge monitoring equipment for monitoring battery stacks with relatively low charge levels; and The controller or one of the monitoring devices manages the cyclical changes of the communication group, such that the communication frequency of the high-charging monitoring device, which is the main communication device, becomes higher than the communication frequency of the low-charging monitoring device, which is the main communication device.

12. The monitoring system according to claim 11, wherein The controller or one of the monitoring devices manages the cyclical changes of the communication group, such that the communication cycle in the group to which the high-charging monitoring device belongs is longer than the communication cycle in the group to which the low-charging monitoring device belongs.

13. The monitoring system according to claim 11, wherein The controller or one of the monitoring devices manages the cyclical changes of the communication group, such that the selection frequency of the high-charging monitoring device as part of the communication group is higher than the selection frequency of the low-charging monitoring device as part of the communication group.

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