vehicle

Abstract

To provide a vehicle that appropriately detects an electric leakage when a plurality of electric leakage detection devices is mounted.SOLUTION: An ECU executes: a step (S100) of obtaining resistance values of insulation resistance of battery packs and of a vehicle body; a step (S106) of determining that electric leakage occurs in the battery pack when the resistance value of the insulation resistance of any of the battery packs is equal to or less than a threshold α (NO in S102); a step (S114) of determining that electric leakage occurs in the vehicle body when the resistance values of the insulation resistance of all of the battery packs are greater than the threshold (YES in S102) and when the resistance value of the insulation resistance of the vehicle body is equal to or less than the threshold; and a step (S112) of turning on each SMR, when the resistance values of the insulation resistance of all of the battery packs and of the vehicle body are greater that the threshold (YES in S102 and YES in S104).SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to vehicles with replaceable batteries. [Background technology]

[0002] For example, Japanese Patent Application Laid-Open Publication No. 2015-082350 (Patent Document 1) discloses a configuration in which a battery management device provided in a battery pack is communicatively connected to various electronic control devices on the vehicle side via a CAN (Controller Area Network) communication network, and transmits information indicating the results of leakage current detection, etc. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-082350 Summary of the Invention [Problem to be solved by the invention]

[0004] However, for example, in a vehicle equipped with a replaceable battery, multiple leakage detection devices for detecting leakage may be installed on the battery side and the vehicle side, and if each leakage detection device detects leakage in parallel, they may interfere with each other and may not be able to detect leakage properly.

[0005] The present disclosure has been made to solve the above-mentioned problems, and its purpose is to provide a vehicle that can appropriately detect a ground fault when multiple ground fault detection devices are installed. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, a vehicle includes a vehicle body, a battery detachable from the vehicle body, a first detection device provided in the battery for detecting the presence or absence of a ground fault, and a second detection device provided in the vehicle body for detecting the presence or absence of a ground fault. Each of the first detection device and the second detection device detects the presence or absence of a ground fault when the battery and an electrical device of the vehicle body are in a first state in which they are electrically disconnected. The second detection device detects the presence or absence of a ground fault when the battery and the electrical device are in a second state in which they are electrically connected.

[0007] In this way, in the first state, the first detection device and the second detection device detect the presence or absence of a leakage current between the battery and the vehicle's electrical equipment, and in the second state, the second detection device detects the presence or absence of a leakage current between the battery and the vehicle's electrical equipment. Therefore, since leakage detection is performed depending on the battery's installation state, it is possible to identify the location of the leakage current while avoiding interference. Therefore, when multiple leakage detection devices are installed, leakage current can be detected appropriately.

[0008] In one embodiment, the second detection device detects the presence or absence of an electric leakage while the second state is in effect and detection of the presence or absence of an electric leakage using the first detection device is stopped.

[0009] In this way, it is possible to detect a ground fault using the second detection device while avoiding interference from other detection devices.

[0010] In yet another embodiment, the vehicle further includes a control device that acquires information about the detection results of the presence or absence of a ground fault from the first detection device and the second detection device. When the vehicle is in the second state, the control device acquires an execution status of the ground fault detection, and uses the acquired execution status to request the first detection device to detect the ground fault or to stop detecting the ground fault.

[0011] In this way, interference between the leakage detection by the first detection device and the leakage detection by the second detection device can be avoided, and leakage detection can be performed with high accuracy. [Effects of the Invention]

[0012] According to the present disclosure, it is possible to provide a vehicle that can appropriately detect a ground fault when multiple ground fault detection devices are installed. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram showing an example of the configuration of a vehicle according to an embodiment of the present invention; [Figure 2] 1 is a diagram illustrating an example of the configuration of a battery exchange system for exchanging a battery pack. [Figure 3] 10 is a flowchart showing an example of a battery pack replacement method. [Figure 4] 4 is a flowchart showing an example of the leakage determination process of FIG. 3. [Figure 5] 10 is a flowchart showing an example of a leakage determination process during Ready-Off. [Figure 6] 10 is a flowchart illustrating an example of a process for setting a state of electric leakage detection. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0015] FIG. 1 is a diagram illustrating an example of the configuration of a vehicle 100 according to this embodiment. Referring to FIG. 1, the vehicle 100 includes a vehicle body 10 and battery packs 20A and 20B. The vehicle body 10 is the portion of the vehicle 100 other than the battery packs 20A and 20B. The vehicle body 10 includes a vehicle drive device serving as a drive source. The vehicle drive device includes a motor generator (MG) 11a and an inverter 11b. The vehicle drive device is configured to run the vehicle 100 using electric power output from each of the battery packs 20A and 20B. The battery packs 20A and 20B are configured to be connectable in parallel to the inverter 11b. The vehicle 100 is, for example, an electric vehicle without an internal combustion engine. However, the present invention is not limited thereto, and the vehicle 100 may be a plug-in hybrid vehicle with an internal combustion engine or another type of electric vehicle. In this embodiment, the battery packs 20A and 20B have the same configuration, and therefore, hereinafter, when there is no need to distinguish between them, they will be referred to as "battery pack 20."

[0016] The vehicle body 10 includes circuits CR11 and CR12. The battery pack 20 includes circuits CR21 and CR22. The circuit CR12 includes an auxiliary battery 17. The circuit CR21 includes a battery 21. The battery 21 is, for example, a secondary battery such as a lithium-ion battery, a nickel-metal hydride battery, or a sodium-ion battery. The type of the secondary battery may be a liquid secondary battery or an all-solid-state secondary battery. A plurality of secondary batteries may form a battery pack. The auxiliary battery 17 corresponds to a low-voltage power supply that outputs power at a voltage lower than that of the battery 21. A DC / DC converter 16 is provided between the circuit CR11 and the circuit CR12.

[0017] The circuit CR11 in the vehicle body 10 includes an MG 11a, an inverter 11b, a DC charging relay 14a, a DC inlet 14b, an AC charger 15a, and an AC inlet 15b. The circuit CR11 is also provided with a ground fault detector 12. The circuit CR21 in the battery pack 20 is provided with a BMS (Battery Management System) 22a and a ground fault detector 22b.

[0018] The vehicle body 10 further includes a terminal T11A to which the battery pack 20A can be detachably attached, a terminal T11B to which the battery pack 20B can be detachably attached, a parallel circuit CR13 that connects the terminals T11A and T11B in parallel, and an SMR (System Main Relay) 13 arranged between the parallel circuit CR13 and the vehicle drive device (inverter 11b). The circuit CR11 is connected to each of the terminals T11A and T11B via the SMR13 and the parallel circuit CR13. Each of the battery packs 20A and 20B includes a terminal T21 to which the vehicle body 10 can be detachably attached, and an SMR23 arranged between the terminal T21 and the circuit CR21. The circuit CR21 is connected to the terminal T21 via the SMR23.

[0019] Terminal T21 of battery pack 20A is connected to terminal T11A of vehicle body 10. SMR 23 of battery pack 20A is disposed between terminal T21 of battery pack 20A and battery 21. Terminal T21 of battery pack 20B is connected to terminal T11B of vehicle body 10. SMR 23 of battery pack 20B is disposed between terminal T21 of battery pack 20B and battery 21. Each relay makes it possible to easily and appropriately switch between connection and disconnection between inverter 11b and each of battery packs 20A and 20B.

[0020] The vehicle body 10 further includes a terminal T12A to which the battery pack 20A can be attached and a terminal T12B to which the battery pack 20B can be attached and detached. A circuit CR12 inside the vehicle body 10 is connected to each of the terminals T12A and T12B via a parallel circuit CR13. The parallel circuit CR13 connects the terminals T12A and T12B in parallel. A communication line CL1 (dashed line in FIG. 1) inside the vehicle body 10 is also connected to each of the terminals T12A and T12B. Each of the battery packs 20A and 20B further includes a terminal T22. In each of the battery packs 20A and 20B, the circuit CR22 and the communication line CL2 (dashed line in FIG. 1) are connected to the terminal T22.

[0021] The auxiliary battery 17 supplies power to drive auxiliary devices mounted on the vehicle 100. The auxiliary battery 17 outputs DC power to the circuit CR12. The circuit CR12 further includes ECUs 18a, 18b, 18c, and 18d in addition to the auxiliary battery 17. The circuit CR22 further includes ECUs 28a and 28b. The auxiliary battery 17 supplies power to each of the ECUs 18a to 18d, 28a, and 28b connected to a low-voltage power supply line, for example.

[0022] The ECU 18a corresponds to a control device (EV-ECU) that manages various controls related to the vehicle 100. The ECU 18b corresponds to a control device (Plg-ECU) that detects the respective states of the DC inlet 14b and the AC inlet 15b. The ECU 18c corresponds to a control device (Bat-C-ECU) that controls the DC charging relay 14a and the AC charger 15a. The ECU 18d corresponds to a control device (first leakage ECU) that monitors the leakage state of the circuit CR11. The ECU 28a corresponds to a control device (Bat-ECU) that monitors the state of the battery 21 and controls the SMR 23. The ECU 28b corresponds to a control device (second leakage ECU) that monitors the leakage state of the circuit CR21.

[0023] Each ECU includes a processor and a storage device. The storage device is configured to be able to save stored information. The storage device stores programs as well as various information used by the programs. In this embodiment, various controls are performed by the processor executing the programs stored in the storage device. However, these processes may also be performed by hardware (electronic circuits) alone, without using software.

[0024] In vehicle 100, the ECUs are connected to each other so that they can communicate with each other via an in-vehicle network (for example, a CAN). ECU 18a acquires information from the other ECUs, controls inverter 11b, DC / DC converter 16, and SMRs 13 and 23, and sends control commands to ECU 18c and ECU 28a.

[0025] The leakage detector 12 detects the leakage state (e.g., insulation resistance) of the circuit CR11 and outputs the detection result to the ECU 18d. The BMS 22a detects the state (current, voltage, temperature, etc.) of the battery 21 and outputs the detection result to the ECU 28a. The leakage detector 22b detects the leakage state of the circuit CR21 and outputs the detection result to the ECU 28b. The ECU 18a obtains information indicating the battery state and the leakage state from the ECUs 18d, 28a, and 28b.

[0026] The DC / DC converter 16 transforms DC power between the circuits CR11 and CR12. Specifically, the DC / DC converter 16 steps down the DC power from the battery 21 and outputs it to the auxiliary battery 17 and other accessories connected to the circuit CR12. The capacity of the battery 21 is larger than that of the auxiliary battery 17.

[0027] Terminals T21 and T22 of battery pack 20A are connected to terminals T11A and T12A, or terminals T21 and T22 of battery pack 20B are connected to terminals T11B and T12B, whereby battery pack 20A and / or battery pack 20B are attached to vehicle body 10 to form vehicle 100. In vehicle 100, communication line CL1 of vehicle body 10, communication line CL2 of battery pack 20A, and communication line CL2 of battery pack 20B are connected. These communication lines form an in-vehicle network of vehicle 100.

[0028] Each of the DC inlet 14b and the AC inlet 15b has a terminal for detecting connection / disconnection of a charging cable (plug), and outputs a signal indicating whether the charging cable is connected to the ECU 18b. The ECU 18a acquires information indicating the inlet state from the ECU 18b, and sends a control command to the ECU 18c. The AC charger 15a performs AC / DC conversion. The ECUs 18a to 18c work together to perform plug-in charging of the battery 21.

[0029] The vehicle body 10 further includes an HMI (Human Machine Interface) 19a and a communication device 19b. The HMI 19a and the communication device 19b also receive power from the auxiliary battery 17. The HMI 19a includes an input device and a display device installed in the vehicle cabin. The HMI 19a may include a touch panel display. The input device outputs a signal corresponding to an input from a user to the ECU 18a. The communication device 19b is configured to be capable of wireless communication with a server 380 (FIG. 2) described later. The vehicle body 10 is also equipped with various sensors (not shown) (representatively referred to as an on-board sensor 19c). The ECU 18a is configured to acquire the detection results of these sensors directly or via another ECU.

[0030] In this embodiment, the HMI 19a includes a start switch. A start switch is generally called a "power switch" or an "ignition switch." By operating the start switch, a user of the vehicle 100 can start or stop the control system (including each ECU) of the vehicle 100, or put the vehicle 100 into a Ready-ON state or a Ready-OFF state.

[0031] The Ready-ON state is a state in which the voltage of at least one battery 21 of battery packs 20A, 20B connected to vehicle body 10 is applied to circuit CR11 of vehicle body 10. In the Ready-ON state, SMR 13 is closed, and at least one SMR 23 of battery packs 20A, 20B is also closed, and power is supplied to the vehicle drive device (MG 11a and inverter 11b) from the battery 21 corresponding to the closed SMR 23. The Ready-OFF state is a state in which the voltage of battery 21 is not applied to circuit CR11. In the Ready-OFF state, SMR 13 is open, and power is not supplied to the vehicle drive device from either battery 21 of battery packs 20A, 20B.

[0032] The battery packs 20A and 20B installed in the vehicle 100 can be replaced with other battery packs. Fig. 2 is a diagram showing an example of the configuration of a battery exchange system for exchanging battery packs. The battery exchange system 300 shown in Fig. 2 is implemented in, for example, a battery exchange station.

[0033] 2, the battery exchange system 300 is configured to remove a battery pack mounted on the vehicle 100 from the vehicle body 10 and install another battery pack on the vehicle body 10. An example will be described below in which two battery packs (battery packs 20A and 20B) are simultaneously removed from the vehicle 100 and two replacement battery packs are simultaneously installed on the vehicle 100. However, this is not limited to this, and the battery packs 20A and 20B may be replaced one by one in order. Battery pack replacement also includes a case in which only one battery pack is installed in the mounting position of either battery pack 20A or battery pack 20B after the two battery packs have been removed.

[0034] Hereinafter, the two battery packs collected from the vehicle 100 will be referred to as "battery packs B11 and B12," and the two battery packs attached to the vehicle 100 in place of the battery packs B11 and B12 will be referred to as "battery packs B21 and B22." Each of the battery packs B11, B12, B21, and B22 has the configuration of the battery pack shown in Fig. 1. The battery packs B21 and B22 function as the battery packs 20A and 20B (Fig. 1) in the vehicle 100.

[0035] Specifically, the battery exchange system 300 includes a first storage device 310, a second storage device 320, a collection device 330, a filling device 340, an exchange device 350, a server 380, and a display device 390. The first storage device 310 stores a plurality of battery packs to be supplied to vehicles. The first storage device 310 includes a pack storage unit (e.g., a hangar) as well as a charger and a supply device. The second storage device 320 stores a plurality of battery packs collected from a plurality of vehicles. The second storage device 320 includes an inspection device and a sorting device as well as a pack storage unit. The server 380 includes a processor, a storage device, and a communication device, and functions as a control device. The storage device stores information (e.g., specification information) about each battery pack present in the battery exchange system 300, distinguishing them by battery pack identification information (pack ID). The display device 390 displays information according to instructions from the server 380.

[0036] A battery replacement method will be described below with reference to Figures 1 to 4. Figure 3 is a flowchart showing an example of a battery pack replacement method. Figure 4 is a flowchart showing an example of the leakage determination process of Figure 3. After the vehicle 100 is parked in a predetermined area in the battery replacement station, the ECU 18a starts the processing flow of S11 to S14 shown in Figure 3. This processing flow may also be started in response to a request from a terminal (user terminal) of the user of the vehicle 100 or an input device in the vehicle 100. The ECU 18a and the server 380 are configured to be capable of wireless communication.

[0037] In step (hereinafter, step will be abbreviated as S) 10, ECU 18a transmits a signal requesting battery pack replacement (hereinafter, referred to as "replacement request signal") to server 380. The replacement request signal includes identification information (vehicle ID) of vehicle 100 and specification information of each battery pack (battery packs B11, B12) installed in vehicle 100. The replacement request signal may include specification information of vehicle body 10 instead of or in addition to the specification information of battery packs B11, B12.

[0038] In S12, the ECU 18a determines whether or not the battery pack has been replaced. While the battery pack replacement is not complete (NO in S12), the determination in S12 is repeatedly executed.

[0039] When the server 380 receives the exchange request signal, it starts the process flow of S31 to S33 in FIG.

[0040] In S31, the server 380 selects a battery pack that matches the specifications of the vehicle 100 indicated by the replacement request signal from the battery packs (inventory) held by the first storage device 310. If it is determined that there is no battery pack in inventory that matches the specifications of the vehicle 100, the server 380 may display a predetermined message on the display device 390 and stop the battery replacement process. If a battery pack is selected in S31, the process proceeds to S32.

[0041] In S32, the server 380 controls the exchange device 350 to remove the battery packs B11 and B12 from the vehicle body 10. This separates the battery packs B11 and B12 from the vehicle body 10. The process then proceeds to S33.

[0042] In S33, the server 380 controls the charger of the first storage device 310 so that the battery pack B21 or B22 selected in S31 is charged. However, the charging timing can be changed as appropriate. A charged battery pack may be loaded into the first storage device 310. When charging is completed, the server 380 controls the supply device of the first storage device 310 so that the battery pack B21 or B22 is transported (supplied) from the first storage device 310 to the exchange device 350. Next, the server 380 controls the exchange device 350 so that the battery pack B21 or B22 is attached to the vehicle body 10. At this time, the SMR 23 of the attached battery pack B21 or B22 is in the open state. Thereafter, the server 380 transmits a signal (hereinafter referred to as the "exchange completion signal") to the ECU 18a notifying that the battery pack attachment is complete.

[0043] FIG. 2 shows an example in which the removal and installation of the battery pack are performed in different positions. The vehicle position may be adjusted before the removal of the battery pack, before the installation of the battery pack, or both. A transport device (e.g., a conveyor-type transport device) or a transport robot (not shown) may move the vehicle. The removal and installation of the battery pack may be performed in the same position. The battery pack may be replaced (removed and installed) while the vehicle is stationary. The transport method for each of the collection device 330, the supply device, and the filling device 340 is also arbitrary. These transport methods may be a conveyor type or a method using a transport robot. Note that the user may manually replace the battery pack (power storage device) without communication between the battery exchange system (station) and the vehicle.

[0044] For example, when battery packs B21 and B22 are attached to vehicle body 10, terminals T21 and T22 of battery pack B21 are connected to terminals T11A and T12A of vehicle body 10, respectively, and terminals T21 and T22 of battery pack B22 are connected to terminals T11B and T12B of vehicle body 10, respectively, resulting in the connection state shown in Fig. 1. When battery packs B21 and B22 are attached to vehicle body 10, circuits CR12 and CR22 and communication lines CL1 and CL2 are connected between vehicle body 10 and battery packs B21 and B22, respectively. Then, the process flow of S21 to S24 shown in Fig. 3 is started in each of battery packs B21 and B22.

[0045] In S21, the ECU 28a is started up by power supplied from the power source (auxiliary battery 17) within the vehicle body 10. Thereafter, the process proceeds to S22.

[0046] In S22, the ECU 28a transmits information indicating the state of the battery pack (hereinafter referred to as "state information") to the ECU 18a. The state information includes, for example, information about the current voltage of the battery 21 detected by the BMS 22a. Note that the state information may also include information about the leakage detection result (leakage state) detected by the leakage detector 22b and the leakage ECU 28b. The voltage of the battery 21 may vary depending on the SOC (State Of Charge) of the battery 21. The SOC is, for example, the ratio of the current amount of charge to the amount of charge in a fully charged state, expressed as 0 to 100%. Thereafter, the process proceeds to S23.

[0047] In S23, the ECU 28a determines whether or not an SMR-on command has been received from the vehicle body 10. The ECU 28a waits in S23 for an SMR-on command from the vehicle body 10 while keeping the SMR 23 open. When the ECU 28a receives the SMR-on command (YES in S23), the process proceeds to S24.

[0048] In S24, the ECU 28a switches the SMR 23 from the open state (disconnected state) to the closed state (connected state).

[0049] On the other hand, when the battery packs B21, B22 are attached to the vehicle body 10, the ECU 18a receives an exchange completion signal (S33) from the server 380. As a result, YES is determined in S12, and the process proceeds to S13.

[0050] In S13, the ECU 18a determines whether or not the above-mentioned status information has been received from the ECU 28a of the battery pack B21 or B22. If the ECU 18a has received the above-mentioned status information from the battery pack (YES in S13), the process proceeds to S14.

[0051] In step S14, the ECU 18a executes a leakage determination process, which will be described below with reference to the flowchart of FIG.

[0052] In S100, the ECU 18a acquires the resistance values ​​of the insulation resistance of each of the battery packs 20A, 20B and the vehicle body 10. The ECU 18a may acquire the resistance values ​​of the insulation resistance from status information received from the ECU 28a of the battery packs 20A, 20B, or may acquire the resistance values ​​of the insulation resistance from the ECU 28b. Furthermore, the ECU 18a acquires the resistance value of the insulation resistance of the vehicle body 10 from the ECU 18d. Then, the process proceeds to S102.

[0053] In S102, ECU 18a determines whether the insulation resistance values ​​of battery packs 20A, 20B are both greater than threshold value α. Threshold value α is a predetermined value for determining whether or not a leakage current exists, and is adapted through experimentation or the like. If it is determined that both resistance values ​​are greater than threshold value α (YES in S102), the process proceeds to S104.

[0054] In S104, ECU 18a determines whether the resistance value of the insulation resistance of vehicle body 10 is greater than threshold value α. Threshold value α has been described above, and detailed description thereof will not be repeated. Note that the threshold value used in the process of S102 may be different from the threshold value used in the process of S104. If it is determined that the resistance value is greater than threshold value α (YES in S104), the process proceeds to S110. Note that if at least one of the resistance values ​​of the insulation resistance of battery packs B21, B22 is equal to or less than threshold value α (NO in S102), the process proceeds to S106.

[0055] In S106, the ECU 18a determines that a leakage current has occurred in one of the battery packs 20A, 20B whose insulation resistance value is equal to or less than the threshold value α. For example, the ECU 18a sets a flag associated with the pack ID of the battery pack whose insulation resistance value is equal to or less than the threshold value α to an ON state. Then, the process proceeds to S108.

[0056] In S108, the ECU 18a executes a first fail-safe process. The first fail-safe process may include at least one of a process of controlling the SMR 23 of the battery pack having the pack ID corresponding to the flag in the ON state to the OFF state, a process of prohibiting the SMR 23 from being switched to the ON state, a process of controlling the SMR 13 to the OFF state, and a process of prohibiting the SMR 13 from being switched to the ON state. The process then ends.

[0057] In S110, the ECU 18a sets the leakage detection of the battery packs 20A, 20B to the OFF state. Specifically, the ECU 18a turns off the switch of the circuit (leakage detector 22b) for detecting the resistance value of the insulation resistance of each of the battery packs 20A, 20B to set the leakage detection to a state in which leakage cannot be detected (detection stopped state). Then, the process proceeds to S112.

[0058] In S112, ECU 18a sets each SMR to the ON state. ECU 18a transmits an SMR ON command to SMR 13 and SMRs 23 of battery packs 20A and 20B. Then, the process ends. If it is determined that the resistance value of the insulation resistance of vehicle body 10 is equal to or less than threshold value α (NO in S104), the process proceeds to S114.

[0059] In S114, the ECU 18a determines that there is a leakage current on the vehicle body 10 side. The ECU 18a sets, for example, a flag indicating that there is a leakage current on the vehicle body 10 side to an ON state. Thereafter, the process proceeds to S116.

[0060] In S116, the ECU 18a executes a second fail-safe process. The second fail-safe process may include a process for controlling the SMR 13 to the OFF state, a process for prohibiting the SMR 13 from being switched to the ON state, and a process for prohibiting the SMRs 23 of the battery packs 20A and 20B from being switched to the ON state. The process then ends.

[0061] The ECU 18a may perform leakage detection in each battery pack when the battery pack is in Ready-OFF state.

[0062] The leakage determination process during Ready-OFF will be described below with reference to Fig. 5. Fig. 5 is a flowchart showing an example of the leakage determination process during Ready-OFF.

[0063] In S200, the ECU 18a determines whether the state is Ready-OFF. The ECU 18a may determine that the state is Ready-OFF if the ECU 18a has received a start switch operation (OFF operation) during Ready-ON and has not subsequently received a start switch operation (ON operation). If it is determined that the state is Ready-OFF (YES in S200), the process proceeds to S202.

[0064] In S202, the ECU 18a turns off the SMR 13 and the SMRs 23 of the battery packs 20A and 20B, and then the process proceeds to S204.

[0065] In S204, the ECU 18a sets the leakage detection of each of the battery packs 20A, 20B to the ON state, and then the process proceeds to S206.

[0066] In S206, the ECU 18a acquires the resistance value of the insulation resistance from each of the battery packs 20A and 20B, after which the process proceeds to S208.

[0067] In S208, ECU 18a determines whether the resistance values ​​of the insulation resistances of battery packs 20A, 20B are both greater than threshold value α. If it is determined that the resistance values ​​are greater than threshold value α (YES in S208), the process proceeds to S210.

[0068] In S210, the ECU 18a determines that there is no leakage in either battery pack 20A, 20B, and then the process proceeds to S212.

[0069] In S212, ECU 18a sets the leakage detection to the OFF state. Then, the process ends. If it is determined that at least one of the resistance values ​​of the insulation resistances of battery packs 20A, 20B is equal to or less than threshold value α (NO in S208), the process proceeds to S214.

[0070] In S214, the ECU 18a determines that a battery pack having an insulation resistance value equal to or less than the threshold value α is leaking electricity. For example, the ECU 18a sets a flag associated with the pack ID of the battery pack having an insulation resistance value equal to or less than the threshold value α to an ON state. Then, the process proceeds to S216.

[0071] In S216, the ECU 18a executes fail-safe processing. The fail-safe processing may include at least one of the following: controlling the SMR 23 of the battery pack having the pack ID corresponding to the flag in the ON state to the OFF state; prohibiting the SMR 23 from being switched to the ON state; controlling the SMR 13 to the OFF state; and prohibiting the SMR 13 from being switched to the ON state. The processing then ends.

[0072] In this way, when the SMR 13 is in the cutoff state during Ready-OFF in the vehicle 100, it is possible to detect the presence or absence of leakage in each of the battery packs 20A, 20B.

[0073] Various types of information are communicated between the vehicle body 10 and each battery pack. Specifically, the ECU 28a transmits information regarding whether the leakage detection of each battery pack is in the on state or the off state and information regarding the resistance value of the insulation resistor to the ECU 18a of the vehicle body 10. Meanwhile, the ECU 18a transmits either a request to set the leakage detection to the on state or a request to set the leakage detection to the off state to the ECU 28a. The ECU 28a of each battery pack sets the leakage detection to either the on state or the off state in response to the request from the ECU 18a. Below, with reference to FIG. 6, an example of a process in which the ECU 18a (vehicle body ECU) requests the ECU 28a (battery ECU) of each battery pack to determine whether or not to perform leakage detection will be described. FIG. 6 is a flowchart showing an example of a process for setting the state of leakage detection.

[0074] As shown in FIG. 6(A), for example, when a start-up operation of the start-up switch is received, the ECU 18a is started up, and as shown in FIG. 6(a), the ECU 28a is also started up.

[0075] As shown in Fig. 6(B), the ECU 18a sets the electric leakage detection of the vehicle body 10 to the ON state (the electric leakage detector 12 to the ON state) and starts communication with the ECU 28a. As shown in Fig. 6(b), the ECU 28a sets the electric leakage detection of the battery pack 20 to the ON state, and transmits an execution status indicating that the electric leakage detection is in the ON state to the ECU 18d as shown in Fig. 6(c).

[0076] As shown in FIG. 6(C), when the ECU 18a receives the execution status, it requests the ECU 28a to turn off the leakage detection of the battery pack 20, as shown in FIG. 6(D).

[0077] As shown in Fig. 6(d), ECU 28a executes a detection request determination process. As shown in the flowchart on the left side of Fig. 6, the detection request determination process includes a step (S300) of determining whether or not there is a request to turn on the electric leakage detection, a step (S302) of setting the electric leakage detection to the ON state if there is a request to turn on the electric leakage detection (YES in S300), a step (S304) of determining whether or not there is a request to turn off the electric leakage detection if there is no request to turn on the electric leakage detection (NO in S300), and a step (S306) of setting the electric leakage detection to the OFF state if there is a request to turn off the electric leakage detection (YES in S304). Therefore, when a request to turn off the electric leakage detection is received from ECU 18a, the electric leakage detection is set to the OFF state.

[0078] As shown in Fig. 6(e), when the execution status indicating that the leakage detection is in the OFF state is transmitted from the ECU 28a, the execution status is received by the ECU 18a as shown in Fig. 6(E). If the SMR 13 is subsequently set to the OFF state during Ready-OFF, the ECU 28a is requested to turn on the leakage detection in the battery pack 20 as shown in Fig. 6(F).

[0079] As shown in FIGS. 6(f) and 6(g), the ECU 28a executes a detection request determination process, sets the earth leakage detection to the ON state, and after the earth leakage detection is performed, the ECU 28a switches to the OFF state. Meanwhile, the ECU 18a executes a termination sequence as shown in FIGS. 6(G) and 6(H), and switches to the OFF state. The ECU 18a sets the timing for switching on the earth leakage detection of the battery packs 20A and 20B using the execution status, thereby preventing interference between the earth leakage detections between the battery packs 20A and 20B and between the battery pack 20 and the vehicle body 10. The ECU 18a transmits the above-described request to the ECU 28a, for example, at the timing for switching on or off the earth leakage detection in the flowcharts of FIGS. 3 and 4. The ECU 18a may request a change in the state of the earth leakage detection of the battery packs 20A and 20B using the state of the earth leakage detection on the vehicle body 10 side.

[0080] As described above, in the vehicle 100 according to the present embodiment, when the battery packs 20A, 20B are electrically disconnected from the electrical equipment of the vehicle body 10, the ECUs 28b and 18d detect the presence or absence of leakage between the battery packs 20A, 20B and the electrical equipment of the vehicle body 10. Therefore, the presence or absence of leakage in each of the battery packs 20A, 20B and the vehicle body 10 can be detected with high accuracy. Furthermore, when the battery packs 20A, 20B are electrically connected to the electrical equipment of the vehicle body 10, the ECU 18d detects the presence or absence of leakage between the battery packs 20A, 20B and the electrical equipment of the vehicle body 10. Because the leakage detection of the battery packs 20A, 20B is set to the off state, it is possible to detect the presence or absence of leakage when the battery packs 20A, 20B are connected to the electrical equipment of the vehicle body 10, while avoiding interference between the leakage detection using the ECU 28b of the battery pack 20 and the leakage detection using the ECU 18d. In this way, since leakage detection is performed depending on the attachment / detachment state of battery packs 20A, 20B, it is possible to identify the location of leakage while avoiding interference, and therefore it is possible to provide a vehicle that can appropriately detect leakage when multiple leakage detection devices are installed.

[0081] Modifications will be described below.

[0082] In the above embodiment, the vehicle 100 is shown as having two battery packs 20A and 20B mounted thereon, but the number of mounted battery packs may be one or three or more.

[0083] Furthermore, in the above-described embodiment, the case where the entity that executes the leakage current determination process is ECU 18a has been described as an example, but the entity that executes the leakage current determination process or the entity that switches SMRs 13 and 23 is not limited to ECU 18a, and may be, for example, ECU 18d or another ECU mounted on vehicle body 10.

[0084] Furthermore, the configuration of the vehicle body shown in FIG. 1 can be modified as appropriate. For example, the SMR 13 of the vehicle body 10 may be omitted, or the SMR 23 of the battery pack 20 may be omitted. Also, at least one of the DC inlet 14b and the AC inlet 15b may be omitted, or may be replaced with a single inlet that is common to AC and DC. These inlets may be configured to enable bidirectional power transmission. The vehicle body may perform external power supply (V2X: Vehicle to Everything) using power output from the attached battery pack.

[0085] The above-described modifications may be implemented in whole or in part in appropriate combination.

[0086] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0087] 10 Body, 18a, 28a ECU, 20A, 20B Battery pack, 21 Battery, 23 SMR, 300 Battery exchange system, 350 Exchange device.

Claims

1. The car body and a battery detachable from the vehicle body; a first detection device provided in the battery for detecting the presence or absence of a leakage current; a second detection device provided on the vehicle body for detecting the presence or absence of an electric leakage; each of the first detection device and the second detection device detects the presence or absence of the leakage current when the battery and the electrical device of the vehicle body are in a first state in which they are electrically disconnected; The second detection device detects the presence or absence of the leakage current when the battery and the electrical device are in a second state in which they are electrically connected.

2. The vehicle according to claim 1 , wherein the second detection device detects the presence or absence of the electric leakage while the vehicle is in the second state and detection of the presence or absence of the electric leakage using the first detection device is stopped.

3. the vehicle further includes a control device that acquires information on the detection results of the presence or absence of the electric leakage from the first detection device and the second detection device, 2. The vehicle according to claim 1, wherein, when the control device is in the second state, the control device acquires the execution status of the detection of the electric leakage, and uses the acquired execution status to either request the first detection device to detect the electric leakage or request that the detection of the electric leakage be stopped.

Images