Storage battery diagnosis device, method, and program

Abstract

The present invention relates to a battery diagnosis device, method, and program for diagnosing the state of a battery mounted in a vehicle, the battery diagnosis device being provided with a processor and a memory. The processor is configured to perform a diagnostic discharge from the battery toward a predetermined in-vehicle device at a second time after a predetermined time elapses from the first time, acquire a physical quantity indicating a state of the battery during the diagnostic discharge, and determine whether or not a deterioration diagnosis of the battery can be performed on the basis of the physical quantity. When it is determined that the deterioration diagnosis of the storage battery can be performed, a predetermined time is recorded as one of a plurality of discharge success times, and when it is determined that the deterioration diagnosis of the storage battery can be performed, the deterioration diagnosis of the storage battery is performed on the basis of the physical quantity.

Description

Technical Field

[0001] The present disclosure relates to a battery diagnostic device, method, and program for diagnosing the state of a battery mounted on a vehicle. Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2022-064649 discloses a battery diagnostic method for performing degradation diagnosis of a secondary battery that can back up a main battery during autonomous driving. In this battery diagnostic method, the following processing is performed: when the degradation diagnosis of the secondary battery cannot be performed by the first diagnostic discharge process, the diagnostic discharge process is repeatedly performed multiple times to increase the opportunity to perform the degradation diagnosis of the secondary battery.

[0003] Even if there are multiple opportunities to perform the degradation diagnosis of the battery as in the battery diagnostic method described in Japanese Unexamined Patent Application Publication No. 2022-064649, if the timing of the diagnostic discharge overlaps with the timing of the current demand related to in-vehicle equipment frequently, it may be necessary to charge and discharge the battery multiple times before the diagnostic discharge process is successful, or all the diagnostic discharge processes may fail. If all the diagnostic discharge processes fail and the degradation diagnosis of the battery cannot be performed, the diagnostic accuracy decreases. Summary of the Invention

[0004] The present disclosure provides a battery diagnostic device and the like that can increase the probability of success of the diagnostic discharge process and improve the diagnostic accuracy of the battery.

[0005] One aspect of the technology of the present disclosure is a battery diagnostic device for diagnosing the state of a battery mounted on a vehicle, including a processor and a memory. The processor is configured to perform a diagnostic discharge from the battery to a specified in-vehicle device at a second timing after a specified time has elapsed from a first timing, obtain a physical quantity indicating the state of the battery during the diagnostic discharge, determine whether the degradation diagnosis of the battery can be performed based on the physical quantity, record the specified time as one of a plurality of discharge success times when it is determined that the degradation diagnosis of the battery can be performed, and perform the degradation diagnosis of the battery based on the physical quantity when it is determined that the degradation diagnosis of the battery can be performed.

[0006] According to the battery diagnostic device and the like of the present disclosure as described above, since the timing of performing the diagnostic discharge process is determined based on the past discharge success times, the diagnostic discharge process can be made successful with a high probability, and the diagnostic accuracy of the battery is improved. Brief Description of the Drawings

[0007] Hereinafter, with reference to the drawings, the features, advantages, technology, and industrial importance of the exemplary embodiments of the present invention will be described. In the drawings, the same reference numerals denote the same components, where:

[0008] Figure 1 It is a functional block diagram of a battery diagnostic device and its peripheral parts related to an embodiment.

[0009] Figure 2 It is a diagram showing the current path released from the second battery during the diagnostic discharge process.

[0010] Figure 3 It is a diagram showing an example of changes in physical quantities of the second battery during the diagnostic discharge process.

[0011] Figure 4 It is a diagram showing an example of the discharge success time recorded by the recording unit.

[0012] Figure 5 It is a diagram showing an example of the discharge failure time recorded by the recording unit.

[0013] Figure 6A It is a flowchart of the battery diagnostic process executed by the battery diagnostic device.

[0014] Figure 6B It is a flowchart of the battery diagnostic process executed by the battery diagnostic device. Detailed Embodiment

[0015] The present disclosure is a battery diagnostic device that implements the deterioration diagnosis of a secondary battery capable of supporting a main battery during autonomous driving. This battery diagnostic device records the timing when the past diagnostic discharge process was successful (or failed), and based on this recorded timing, it executes the future diagnostic discharge process. Thus, since the battery diagnostic process can be performed at a timing with a high probability of success in the diagnostic discharge process, the diagnostic accuracy of the battery can be improved.

[0016] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings.

[0017] <Embodiment>

[0018] [Configuration]

[0019] Figure 1 It is a functional block diagram of a battery diagnostic device 100 and its peripheral parts related to an embodiment of the present disclosure. Figure 1 The exemplified functional modules include a first battery 11, a second battery 12, a first vehicle-mounted device 21, a second vehicle-mounted device 22, a connection switching unit 30, a generator 40, a control unit 60, and a battery diagnostic device 100.

[0020] The first battery 11, the first vehicle-mounted device 21, the connection switching unit 30, and the generator 40 are interconnected via the first power line 51. The second battery 12 and the connection switching unit 30 are connected via the second power line 52. The second vehicle-mounted device 22 and the connection switching unit 30 are connected via the third power line 53. In addition, the second battery 12, the connection switching unit 30, the control unit 60, and the battery diagnostic device 100 are connected via a signal line ( Figure 1 the dashed line in

[0021] ), and control signals, measured values, etc. are transmitted and received.

[0022] The generator 40 is, for example, a device such as an alternator or a DC-DC converter that can output a specified power. The power output by the generator 40 is supplied to the first battery 11, the first vehicle-mounted device 21, etc.

[0023] The first battery 11 is, for example, a secondary battery such as a lead-acid battery or a lithium-ion battery that is configured to be capable of charge and discharge. The first battery 11 stores the power output by the generator 40, or releases the power stored in itself to the first vehicle-mounted device 21 and the connection switching unit 30. The first battery 11 is provided as a main battery dedicated to the running of the vehicle.

[0024] The second battery 12 is, for example, a secondary battery such as a lead-acid battery or a lithium-ion battery that is configured to be capable of charge and discharge. The second battery 12 stores the power output by the generator 40 and the power of the first battery 11 via the connection switching unit 30, or releases (supplies) the power stored in itself to the second vehicle-mounted device 22, etc. via the connection switching unit 30. The second battery 12 is redundantly provided so that even when the first battery 11 fails during autonomous driving, it can perform backup processing to maintain the power supply to the second vehicle-mounted device 22 responsible for autonomous driving in place of the first battery 11.

[0025] The first vehicle-mounted device 21 is a power-consuming load mounted on the vehicle. The first vehicle-mounted device 21 is configured to operate using the power output by the generator 40 and / or the power stored in the first battery 11.

[0026] The second vehicle-mounted device 22 is a power-consuming load mounted on a vehicle, and can be a device that requires a more stable power supply than the first vehicle-mounted device 21 during the autonomous driving of the vehicle. More specifically, the second vehicle-mounted device 22 is an important device related to the safe driving of the vehicle that requires power supply from the second battery 12 for a specified period and a specified current even when the power supply related to the first battery 11 fails. For example, it can be a device that is responsible for an important function for safely avoiding the vehicle in an emergency during autonomous driving. The second vehicle-mounted device 22 is configured to operate with the power output by the generator 40 and / or the power stored in the first battery 11 during manual driving, and operate with the power output by the generator 40 whose voltage is controlled by the DCDC converter 33 and / or the power stored in the first battery 11 and the power stored in the second battery 12 during autonomous driving.

[0027] The connection switching unit 30 includes a first switch 31, a second switch 32, and a DCDC converter 33 in its configuration. The first switch 31 is disposed between the first power line 51 and the third power line 53 in an openable and closable manner. The second switch 32 is disposed between the second power line 52 and the third power line 53 in an openable and closable manner. The first switch 31 and the second switch 32 can use, for example, semiconductor relays, mechanical relays, etc. The DCDC converter 33 is a voltage converter that is disposed between the first power line 51 and the second power line 52 and converts the voltage of the input power into a specified voltage for output. The DCDC converter 33 can be, for example, a buck-boost type DCDC converter that has both a buck function of stepping down the voltage on the primary side and outputting it to the secondary side and a boost function of stepping up the voltage on the secondary side and outputting it to the primary side.

[0028] The control unit 60 is constituted by, for example, an autonomous driving ECU (Electronic Control Unit) including a microcomputer, etc., and controls the open / close states of the first switch 31 and the second switch 32 of the connection switching unit 30 and the voltage indication value of the DCDC converter 33 based on vehicle information (the on / off state of the ignition device, the manual driving / autonomous driving state, etc.) obtained from vehicle-mounted devices (not shown).

[0029] Specifically, when the vehicle is in the manual driving state, the control unit 60 closes the first switch 31 to connect the first power line 51 to the third power line 53, and opens the second switch 32 to disconnect the second power line 52 from the third power line 53. Thereby, the power output from the generator 40 and / or the power stored in the first battery 11 is directly supplied to the second vehicle-mounted device 22. On the other hand, when the vehicle is in the autonomous driving state, the control unit 60 opens the first switch 31 to disconnect the first power line 51 from the third power line 53, and closes the second switch 32 to connect the second power line 52 to the third power line 53. Thereby, the power output from the generator 40 and / or the power stored in the first battery 11 is indirectly supplied to the second vehicle-mounted device 22 via the DCDC converter 33.

[0030] The battery diagnostic device 100 is a device for diagnosing the state of the second battery 12. More specifically, it can perform diagnosis related to the deterioration of the second battery 12. This battery diagnostic device 100 includes a discharge processing unit 101, an acquisition unit 102, a determination unit 103, a recording unit 104, and a diagnostic unit 105 in its configuration.

[0031] When the timing for performing the deterioration diagnosis of the second battery 12 arrives, the discharge processing unit 101 performs a diagnostic discharge process of discharging from the second battery 12 to the first vehicle-mounted device 21 and the second vehicle-mounted device 22 for a first period of time. The timing for performing this deterioration diagnosis is determined based on the discharge success time or discharge failure time recorded by the recording unit 104 described later, and is updated at any time.

[0032] Figure 2 shows the current release path in the diagnostic discharge process performed by the discharge processing unit 101 ( Figure 2 arrow). Current is released to the first vehicle-mounted device 21 via the DCDC converter (DDC) 33, and current is released to the second vehicle-mounted device 22 via the second switch 32. Additionally, Figure 3 shows the change in the outflow current and output voltage of the second battery 12 during the diagnostic discharge. As Figure 3 shown, during the diagnostic discharge, a current controlled to a constant value Ia by the DCDC converter (DDC) 33 continuously flows out of the second battery 12 for the first period of time. This constant value Ia is appropriately set based on the fact that a current (backup actual current) must continuously flow from the second battery 12 to the second vehicle-mounted device 22 for the first period of time (for example, 15 seconds) during the backup process. This diagnostic discharge process can be further repeated one or two times based on the determination result of the determination unit 103 described later.

[0033] The acquisition unit 102 acquires a physical quantity indicating the state of the second battery 12 during the diagnostic discharge process performed by the discharge processing unit 101. The physical quantity indicating the state of the second battery 12 can be acquired from a detection device such as a sensor (not shown) mounted on the vehicle. Examples of the physical quantity indicating the state of the second battery 12 include voltage, current, and temperature. In the present embodiment, the acquisition unit 102 acquires the current (outflow current) released from the second battery 12 and the output voltage as physical quantities. In addition, the acquisition unit 102 can also obtain the internal resistance and the state of charge (SOC) based on the voltage, current, and temperature.

[0034] The determination unit 103 determines whether a diagnosis related to the deterioration of the second battery 12 can be performed based on the physical quantity indicating the state of the second battery 12 acquired by the acquisition unit 102. For example, the deterioration diagnosis of the second battery 12 is performed according to whether the power that can be supplied by the second battery 12 derived from the outflow current and the output voltage of the second battery 12 obtained through the diagnostic discharge process satisfies the power required as a backup power source for the first battery 11. Therefore, the accuracy of the outflow current and the output voltage of the second battery 12 acquired by the acquisition unit 102 is required. The determination unit 103 determines whether a deterioration diagnosis of the second battery 12 can be performed based on whether the accuracy of the outflow current and the output voltage of the second battery 12 acquired by the acquisition unit 102 is high. The accuracy of the outflow current and the output voltage of the second battery 12 will be described later.

[0035] When it is determined in the determination unit 103 that a diagnosis related to the deterioration of the second battery 12 can be performed, the recording unit 104 records the time from a pre-determined reference timing (first timing) to the timing (second timing) of performing the deterioration diagnosis of the second battery 12 as the discharge success time. Figure 4 An example of the discharge success time recorded by the recording unit 104 is shown. In Figure 4 In the example, the number of times of the discharge success time is cumulatively recorded for each arbitrarily determined time division. In this case, the timing of the deterioration diagnosis of the second battery 12 performed by the discharge processing unit 101 is determined based on Figure 4 the enclosed discharge success time (adoption) shown by the dotted line.

[0036] In addition, when it is determined in the determination unit 103 that a diagnosis related to the deterioration of the second battery 12 cannot be performed, the recording unit 104 may record the time from the reference timing (first timing) to the timing (second timing) of performing the deterioration diagnosis of the second battery 12 as the discharge failure time. Figure 5 An example of the discharge failure time recorded by the recording unit 104 is shown. In Figure 5In the example, the number of times of discharge failure time is cumulatively recorded for each arbitrarily determined time division. In this case, the timing of the deterioration diagnosis of the second battery 12 performed by the discharge processing unit 101 is based on Figure 5 the time other than the discharge failure time (not adopted) enclosed by the dashed line.

[0037] The discharge success time and discharge failure time recorded by the recording unit 104 are reset, for example, when the second battery 12 or the electronic control unit (ECU) of the consumption current is replaced.

[0038] When the determination unit 103 determines that the diagnosis related to the deterioration of the second battery 12 can be performed, the diagnosis unit 105 performs the deterioration diagnosis of the second battery 12 based on the physical quantities (outflow current and output voltage) indicating the state of the second battery 12 acquired by the acquisition unit 102. In this deterioration diagnosis, it is diagnosed whether the second battery 12 is in a state where it can provide backup at the time of failure of the first battery 11.

[0039] Among them, part or all of the above battery diagnosis device 100 can typically be configured as an electronic control device (ECU) such as a microcomputer including a processor, a memory, and an input / output interface, etc. By the processor reading and executing the program stored in the memory, this electronic control device can realize part or all of the functions of the discharge processing unit 101, the acquisition unit 102, the determination unit 103, the recording unit 104, and the diagnosis unit 105.

[0040] [Control]

[0041] Next, with reference to Figure 6A and Figure 6B the control executed by the battery diagnosis device 100 according to the present embodiment will be described. Figure 6A and Figure 6B are flowcharts for explaining the steps of the diagnosis process (battery diagnosis process) related to the deterioration of the second battery 12 performed by each component of the battery diagnosis device 100 during manual driving. Figure 6A The process of Figure 6B is connected by connectors X and Y to the process of

[0042] If the ignition device of the vehicle becomes in the on state (IG-ON), then Figure 6A and Figure 6B the battery diagnosis process exemplified starts. In addition, this battery diagnosis process ends at the moment of switching from driving based on manual driving to driving based on autonomous driving.

[0043] (Step S601)

[0044] The discharge processing unit 101 determines whether the timing (second timing) for performing the diagnostic discharge processing has arrived. The second timing can be determined by any of the following methods, for example, based on the timing (first timing) when the ignition device of the vehicle is turned on (IG-ON). In addition, the timing of the reference is not limited to IG-ON, and any timing that serves as an absolute reference can be determined.

[0045] The first method is to set the second timing to the time when the discharge success time recorded by the recording unit 104 has the largest number of discharge success times since the first timing. By determining the second timing based on the time when the diagnostic discharge treatment succeeded most in the past as in the first method, the probability of the current diagnostic discharge treatment succeeding can be increased.

[0046] The second method is to set the second timing as the time obtained by averaging the discharge success times recorded by the recording unit 104 from the first timing. By determining the second timing based on the average of the times when the diagnostic discharge treatment was successful in the past as in the second method, the probability of the current diagnostic discharge treatment being successful can be increased.

[0047] The third method is a method of setting the second timing to a time that has passed from the first timing by any time other than the discharge failure time recorded in the recording unit 104. By determining the second timing from the time obtained by excluding the time when the past diagnostic discharge process failed as in the third method, the probability of failure of the current diagnostic discharge process can be reduced and the probability of success can be increased.

[0048] The process waits until the timing (second timing) to execute the diagnostic discharge process comes ( S601 , No), and when the timing (second timing) comes ( S601 , Yes), the process proceeds to step S602 .

[0049] (Step S602)

[0050] The discharge processing unit 101 performs the first diagnostic discharge processing. As described above, the discharge processing unit 101 discharges the first vehicle-mounted device 21 and the second vehicle-mounted device 22 ( Figure 2 ) a current of a constant value Ia flowing during the first time ( Figure 3 ) to perform diagnostic discharge. During the diagnostic discharge, the physical quantity of the second storage battery 12 is appropriately acquired by the acquisition unit 102. When the first diagnostic discharge process is performed, the process proceeds to step S603.

[0051] (Step S603)

[0052] The determination unit 103 determines whether it is possible to perform a diagnosis related to the deterioration of the second battery 12. This determination is made based on whether the physical quantity of the second battery 12 acquired by the acquisition unit 102 satisfies the following conditions, for example.

[0053] (1) The average value of the outflow current of the second battery 12 during the first time of the discharge period is not equal to or greater than the first threshold value

[0054] (2) The outflow current of the second battery 12 at the end of the discharge after the first time ( Figure 3 the measurement point) is not equal to or greater than the second threshold value

[0055] Condition (1) assumes a situation where a large current demand that cannot be absorbed by the control of the DCDC converter 33 is generated in the second vehicle-mounted device 22. In such a situation, the current supplied from the second battery 12 to the second vehicle-mounted device 22 during the diagnostic discharge is disordered, and the deterioration of the battery cannot be accurately diagnosed based on the physical quantity of the second battery 12 acquired by the acquisition unit 102. Therefore, the determination of condition (1) is performed. The first threshold value is appropriately set based on the current of a certain value Ia flowing during the diagnostic discharge and the backup actual current.

[0056] Condition (2) assumes a situation where, even when condition (1) above is satisfied, the outflow current of the second battery 12 changes significantly at the end of the discharge after the first time. In such a situation, the available power supply of the second battery 12 (= outflow current × output voltage) derived from the physical quantity of the second battery 12 acquired by the acquisition unit 102 fluctuates, and the deterioration of the battery cannot be accurately diagnosed. Therefore, the determination of condition (2) is performed. The second threshold value is appropriately set based on the power supply required for the second battery 12 as a backup power source for the first battery 11.

[0057] If either of these conditions (1) and (2) is not satisfied, that is, when the average value of the outflow current of the second battery 12 during the first time is equal to or greater than the first threshold value, or the outflow current of the second battery 12 at the end of the discharge after the first time is equal to or greater than the second threshold value, the determination unit 103 determines that it is not possible to perform the battery deterioration diagnosis.

[0058] When it is possible to perform the deterioration diagnosis of the second battery 12 (S603, Yes), the process proceeds to step S614. On the other hand, when it is not possible to perform the deterioration diagnosis of the second battery 12 (S603, No), the process proceeds to step S604.

[0059] (Step S604)

[0060] The recording unit 104 records the time from the first timing (the moment when the vehicle becomes IG-ON) to the start of the first diagnostic discharge process (the second timing in this case) as the discharge failure time. If the discharge failure time is recorded, the process proceeds to step S605.

[0061] (Step S605)

[0062] The discharge processing unit 101 charges the second battery 12 to prepare for the second diagnostic discharge process. This charging is performed by the discharge processing unit 101 instructing the control unit 60 to control the DCDC converter 33. If the second battery 12 is charged, the process proceeds to step S606.

[0063] (Step S606)

[0064] The discharge processing unit 101 determines whether the stored charge of the second battery 12 has reached a specified stored charge (the first stored charge). This determination is made to prepare for the case of continuing to perform the third diagnostic discharge process after the second diagnostic discharge process. That is, the stored charge is increased in advance so that even if the diagnostic discharge is performed twice in a row, the stored charge of the second battery 12 does not decrease excessively. Charging continues until the stored charge of the second battery 12 reaches the first stored charge (S606, no), and if the stored charge of the second battery 12 reaches the first stored charge (S606, yes), the process proceeds to step S607.

[0065] (Step S607)

[0066] The discharge processing unit 101 performs the second diagnostic discharge process (re-diagnostic discharge process). Regarding the diagnostic discharge, as described above. To achieve the stabilization of the discharge current of the second battery 12, it is preferable to perform the second diagnostic discharge process during a period when the large current demand related to the second in-vehicle device 22 that occurred in the first diagnostic discharge process does not occur. The timing of this implementation can be determined based on the discharge success time or the discharge failure time recorded by the recording unit 104. During the period of performing this diagnostic discharge, the acquisition unit 102 appropriately acquires the physical quantity of the second battery 12. If the second diagnostic discharge process is performed, the process proceeds to step S608.

[0067] (Step S608)

[0068] The determination unit 103 determines whether a diagnosis related to the deterioration of the second battery 12 can be performed. Regarding this determination, as described above. If a deterioration diagnosis of the second battery 12 can be performed (S608, yes), the process proceeds to step S614. On the other hand, if a deterioration diagnosis of the second battery 12 cannot be performed (S608, no), the process proceeds to step S609.

[0069] (Step S609)

[0070] The recording unit 104 records the time from the first timing (the moment when the vehicle becomes IG-ON) to the start of the second diagnostic discharge process as the discharge failure time. If the discharge failure time is recorded, the process proceeds to step S610.

[0071] (Step S610)

[0072] The discharge processing unit 101 determines whether a specified time (second time) has elapsed since the end of the second diagnostic discharge process. This determination is made to prepare for the implementation of the third diagnostic discharge process. That is, since the second battery 12 may become polarized immediately after discharging a certain current (CC discharge) through the second diagnostic discharge process, this is done to eliminate the influence of polarization. Therefore, the specified time (second time) is set to a sufficient time until the polarization of the second battery 12 is eliminated. While the time is being counted before the specified time has elapsed (S610, No), if the specified time has elapsed (S610, Yes), the process proceeds to step S611.

[0073] (Step S611)

[0074] The discharge processing unit 101 performs the third diagnostic discharge process (re-diagnostic discharge process). Regarding the diagnostic discharge, as described above. The reason for performing the third diagnostic discharge process immediately after the second diagnostic discharge process is that even if a large current demand related to the second in-vehicle device 22 occurs during the second diagnostic discharge process, it is highly likely that it will not occur during this third diagnostic discharge process. During the performance of this diagnostic discharge, the acquisition unit 102 appropriately acquires the physical quantity of the second battery 12. If the third diagnostic discharge process has been performed, the process proceeds to step S612.

[0075] (Step S612)

[0076] The determination unit 103 determines whether a diagnosis related to the deterioration of the second battery 12 can be performed. Regarding this determination, as described above. In the case where a deterioration diagnosis of the second battery 12 can be performed (S612, Yes), the process proceeds to step S614. On the other hand, in the case where a deterioration diagnosis of the second battery 12 cannot be performed (S612, No), the process proceeds to step S613.

[0077] (Step S613)

[0078] The recording unit 104 records the time from the first timing (the moment when the vehicle becomes IG-ON) to the start of the third diagnostic discharge process as the discharge failure time. When the discharge failure time is recorded, the process proceeds to step S616.

[0079] (Step S614)

[0080] The recording unit 104 records the time from the first timing (the moment when the vehicle becomes IG-ON) to the start of the diagnostic discharge process as the discharge success time. In this process, when it is determined in the first diagnostic discharge process that the deterioration diagnosis of the second battery 12 can be performed (S603, Yes), the time from the first timing to the start of the first diagnostic discharge process (the second timing) is recorded as the discharge success time. When it is determined in the second diagnostic discharge process that the deterioration diagnosis of the second battery 12 can be performed (S608, Yes), the time from the first timing to the start of the second diagnostic discharge process is recorded as the discharge success time. When it is determined in the third diagnostic discharge process that the deterioration diagnosis of the second battery 12 can be performed (S612, Yes), the time from the first timing to the start of the third diagnostic discharge process is recorded as the discharge success time. When the discharge success time is recorded, the process proceeds to step S615.

[0081] (Step S615)

[0082] The diagnostic unit 105 performs a diagnosis related to the deterioration of the second battery 12. This deterioration diagnosis is performed based on whether the power that can be supplied by the second battery 12 can ensure the power for backup when the first battery 11 fails, according to the physical quantity of the second battery 12 obtained by the acquisition unit 102. More specifically, when it is determined in the first diagnostic discharge process that the deterioration diagnosis of the second battery 12 can be performed (S603, Yes), the physical quantity of the second battery 12 obtained by the acquisition unit 102 in the first diagnostic discharge is used for the diagnosis. When it is determined in the second diagnostic discharge process that the deterioration diagnosis of the second battery 12 can be performed (S608, Yes), the physical quantity of the second battery 12 obtained by the acquisition unit 102 in the second diagnostic discharge is used for the diagnosis. When it is determined in the third diagnostic discharge process that the deterioration diagnosis of the second battery 12 can be performed (S612, Yes), the physical quantity of the second battery 12 obtained by the acquisition unit 102 in the third diagnostic discharge is used for the diagnosis. If the deterioration state of the second battery 12 is diagnosed, this battery diagnosis process ends.

[0083] (Step S616)

[0084] Since it is determined that the degradation diagnosis of the second battery 12 cannot be performed in the three diagnostic discharge processes, the diagnosis unit 105 determines that the state of the second battery 12 is abnormal. If it is determined that the state of the second battery 12 is abnormal, this battery diagnosis process ends.

[0085] <Function / Effect>

[0086] As described above, according to the battery diagnosis device 100 according to an embodiment of the present disclosure, when a highly accurate physical quantity for performing the degradation diagnosis of the second battery 12 cannot be obtained through the first diagnostic discharge process (the first diagnostic discharge), the diagnostic discharge process (the second or third diagnostic discharge) is repeatedly performed multiple times to obtain a physical quantity. Through this process, since the possibility of obtaining a highly accurate physical quantity becomes higher, the opportunity to perform the degradation diagnosis of the second battery 12 increases.

[0087] In addition, according to the battery diagnosis device 100 according to the present embodiment, the timing of performing the first diagnostic discharge process (the first diagnostic discharge) is determined based on the past discharge success time or discharge failure time. Therefore, the battery diagnosis process can be performed at a timing with a high probability of success in the diagnostic discharge process, and the diagnosis accuracy of the battery is improved.

[0088] As described above, an embodiment of the present disclosure has been described, but the present disclosure can be understood as a battery diagnosis device, a method executed by a battery diagnosis device including a processor and a memory, a program for executing the method, a computer-readable non-transitory storage medium storing the program, and a vehicle equipped with the battery diagnosis device, etc.

[0089] The battery diagnosis device etc. of the present disclosure can be used in diagnosing the state of a battery mounted on a vehicle.

Claims

1. A battery diagnostic device configured to diagnose the state of a battery mounted on a vehicle, characterized in that: including a processor and memory, in, The processor is configured to perform diagnostic discharge from the battery toward a predetermined vehicle-mounted device at a second timing when a predetermined time has elapsed from the first timing, The processor is configured to obtain a physical quantity indicating a state of the battery during the diagnostic discharge. The processor is configured to determine whether or not the battery degradation diagnosis can be performed based on the physical quantity. The processor is configured to record the predetermined time as one of a plurality of successful discharge times when it is determined that the battery degradation diagnosis can be performed. The processor is configured to perform degradation diagnosis of the battery based on the physical quantity when determining that degradation diagnosis of the battery can be performed.

2. The battery diagnostic device according to claim 1, characterized in that: The processor is configured to perform the diagnostic discharge at the second timing when the discharge success time at which the number of times recorded in the memory is the largest is set as the predetermined time.

3. The battery diagnostic device according to claim 1, characterized in that: The processor is configured to perform the diagnostic discharge at the second timing with an average value of the plurality of discharge success times recorded in the memory being the predetermined time.

4. The battery diagnostic device according to claim 1, characterized in that: When it is determined that the battery degradation diagnosis cannot be performed, the processor records the predetermined time as a discharge failure time. The processor is configured to perform the diagnostic discharge at the second timing with a time other than the discharge failure time recorded in the memory as the predetermined time.

5. The battery diagnostic device according to claim 4, characterized in that: The processor is configured to, when it is determined that the battery cannot be diagnosed for deterioration, discharge the battery for re-diagnosis toward a predetermined vehicle-mounted device at a third timing when a time other than the discharge failure time recorded in the memory has elapsed since the first timing.

6. The battery diagnostic device according to any one of claims 1 to 5, characterized in that: The first timing is a timing when an ignition of the vehicle is turned on.

7. A method, executed by a computer of a battery diagnosis device for diagnosing the state of a battery mounted on a vehicle, characterized in that: include: performing diagnostic discharge from the battery toward a predetermined vehicle-mounted device at a second timing after a predetermined time has passed from the first timing; acquiring a physical quantity indicating a state of the battery during the diagnostic discharge; determining whether or not the battery degradation diagnosis can be performed based on the physical quantity; When it is determined that the battery degradation diagnosis can be performed, recording the predetermined time as one of a plurality of successful discharge times; as well as If it is determined that the battery degradation diagnosis can be performed, the battery degradation diagnosis is performed based on the physical quantity.

8. A program executed by a computer of a battery diagnosis device for diagnosing the state of a battery mounted on a vehicle, characterized in that: include: performing diagnostic discharge from the battery toward a predetermined vehicle-mounted device at a second timing when a predetermined time has elapsed from the first timing; acquiring a physical quantity indicating a state of the battery during the diagnostic discharge; determining whether or not the battery degradation diagnosis can be performed based on the physical quantity; When it is determined that the battery degradation diagnosis can be performed, recording the predetermined time as one of a plurality of successful discharge times; as well as If it is determined that the battery degradation diagnosis can be performed, the battery degradation diagnosis is performed based on the physical quantity.

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