Vehicle battery deterioration determination device

Abstract

To provide a battery for a vehicle deterioration determination device that can accurately determine deterioration of a battery.SOLUTION: A battery for a vehicle deterioration determination device comprises: an acquisition unit that acquires battery information on a battery mounted on a vehicle; a calculation unit that calculates the degree of deterioration of the battery based on the battery information; a determination unit that determines deterioration of the battery based on whether the degree of deterioration exceeds a threshold; a selection unit that, in association information associating with each other a plurality of conditions for use of the battery and offset values used for changing the threshold, selects an offset value associated with an established condition for use; and a changing unit that changes the threshold based on the offset value selected by the selection unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle battery deterioration determination device. [Background technology]

[0002] A technology has been developed that calculates the degree of deterioration of a battery installed in a vehicle based on information about the battery, and compares the calculated degree of deterioration with a preset threshold value to determine the deterioration of the battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-156217 [Patent Document 2] Japanese Patent Publication No. 2020-45782 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above technology, a fixed threshold value is used to determine battery degradation regardless of the battery usage conditions, which may result in unnecessary determination of battery degradation, resulting in low accuracy in determining battery degradation.

[0005] The present invention has been made in view of the above, and has an object to provide a vehicle battery deterioration determination device that can determine battery deterioration with high accuracy. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, a vehicle battery deterioration determination device according to the present invention is Used to determine deterioration ofa calculation unit that calculates a deterioration level of the battery based on the battery information; a determination unit that determines deterioration of the battery based on whether the deterioration level exceeds a threshold; a selection unit that selects an offset value that is associated with a use condition that is established in correspondence information that associates each of a plurality of use conditions of the battery with an offset value used to change the threshold; and a selection unit that selects an offset value that is associated with a use condition that is established in correspondence information that associates each of a plurality of use conditions of the battery with an offset value used to change the threshold. The integrated value of Based on The battery information is offset, and based on the offset battery information, a change unit that changes the threshold value; The plurality of usage conditions include at least two of the following: a mileage of the vehicle, a frequency of electrical loads on the battery, an age of the battery, a first number of intermediate deterioration determinations, a second number of intermediate deterioration determinations, a number of days the vehicle has been left unused, and a temperature of the battery; the first number of intermediate deterioration determinations is the number of times that the voltage of the battery during a predetermined period after the start of the vehicle is started is equal to or lower than a first determination threshold for determining that the battery is deteriorated; and the second number of intermediate deterioration determinations is the number of times that the voltage of the battery during a predetermined period after the start of the vehicle is started is equal to or lower than a second determination threshold that is lower than the first determination threshold. .

[0007] According to this configuration, the threshold value used to determine the deterioration of the vehicle's battery is changed depending on the usage conditions of the battery, and it is possible to prevent the battery from being determined to be deteriorated even when it is not, thereby making it possible to determine the deterioration of the battery with high accuracy.

[0008] In the vehicle battery deterioration determination device according to the present invention, the plurality of usage conditions include tiered usage conditions for the battery.

[0009] This configuration can prevent frequent determinations of battery degradation.

[0010] In the vehicle battery deterioration determination device according to the present invention, the selection unit and the change unit are provided in the vehicle or the server.

[0011] According to this configuration, by providing a change unit in the server, it is not necessary to change the threshold for each vehicle on the market, which makes it easier to change the threshold. Also, by providing a change unit in the vehicle, it is possible to change the threshold without using a server. [Effects of the Invention]

[0012] The vehicle battery deterioration determination device according to the present invention has the effect of being able to determine battery deterioration with high accuracy. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing an example of the overall configuration of a vehicle battery deterioration determination system according to this embodiment. [Figure 2] FIG. 2 is a diagram showing an example of the hardware configuration of the data management server and the vehicle included in the vehicle battery deterioration determination system according to this embodiment. [Figure 3] FIG. 3 is a diagram for explaining an example of the change over time in the voltage of the battery when the engine of the vehicle is started in the vehicle battery deterioration determination system according to this embodiment. [Figure 4] FIG. 4 is a diagram showing an example of the functional configuration of the vehicle and the data management server of the vehicle battery deterioration determination system according to this embodiment. [Figure 5] FIG. 5 is a flowchart showing an example of the flow of the battery degradation determination process in the vehicle battery degradation determination system according to this embodiment. [Figure 6] FIG. 6 is a flowchart showing an example of the flow of the degradation determination process at the start of use of the battery in the vehicle battery degradation determination system according to this embodiment. [Figure 7] FIG. 7 is a flowchart showing an example of the flow of the offset value setting process in the vehicle battery deterioration determination system according to this embodiment. [Figure 8] FIG. 8 is a flowchart showing an example of the flow of the threshold value changing process in the vehicle battery deterioration determination system according to this embodiment. [Figure 9] FIG. 9 is a diagram for explaining an example of the battery degradation determination process in the vehicle battery degradation determination system according to this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle battery deterioration determination system to which a vehicle battery deterioration determination device according to the present invention is applied will be described in detail below with reference to the accompanying drawings.

[0015] 1 is a diagram showing an example of the overall configuration of a vehicle battery deterioration determination system 1 according to this embodiment. First, an example of the overall configuration of a vehicle battery deterioration determination system 1 according to this embodiment will be described with reference to FIG.

[0016] 1, a vehicle battery deterioration determination system 1 according to this embodiment includes a data management server 2 (an example of a server), a vehicle 3 (an example of a vehicle), a dealer terminal 4, and a user terminal 5. The data management server 2, the vehicle 3, the dealer terminal 4, and the user terminal 5 are connected to each other so as to be able to communicate with each other via a network NT such as the Internet.

[0017] The vehicle 3 transmits vehicle information to the data management server 2 via the network NT. Here, the vehicle information is information related to the vehicle 3, and includes battery information related to the battery 35 (see FIG. 2) installed in the vehicle 3. Here, the battery information is information used to determine the deterioration of the battery 35.

[0018] The data management server 2 receives vehicle information from the vehicle 3. Then, the data management server 2 calculates the deterioration level of the battery 35 based on the battery information included in the received vehicle information. Next, the data management server 2 determines the deterioration of the battery 35 based on whether the calculated deterioration level exceeds a threshold, and transmits the resulting deterioration determination result to the dealer terminal 4 via the network NT. In addition, the data management server 2 changes the threshold used to determine the deterioration of the battery 35 depending on the usage conditions of the battery 35. In this embodiment, the data management server 2 functions as an example of a vehicle battery deterioration determination device.

[0019] In this embodiment, the data management server 2 transmits the deterioration determination result to the dealer terminal 4, but this is not limited thereto, and the deterioration determination result may be transmitted directly to the user terminal 5 without going through the dealer terminal 4. Also, in this embodiment, the data management server 2 performs the deterioration determination of the battery 35 and changes the threshold value, but this is not limited thereto, and at least one of the deterioration determination of the battery 35 and the change of the threshold value may be performed in the vehicle 3. When the deterioration determination of the battery 35 is performed in the vehicle 3, the data management server 2 may transmit the change result of the threshold value to the vehicle 3.

[0020] The dealer terminal 4 receives the deterioration determination result of the battery 35 from the data management server 2. Then, based on the received deterioration determination result, the dealer terminal 4 notifies the user terminal 5 of the user of the vehicle 3 to urge the user to replace the battery 35, etc.

[0021] 2 is a diagram showing an example of the hardware configuration of the data management server 2 and the vehicle 3 included in the vehicle battery deterioration determination system according to this embodiment. Next, an example of the hardware configuration of the data management server 2 and the vehicle 3 will be described with reference to FIG.

[0022] As shown in FIG. 2, the vehicle 3 includes an ECU (Electronic Control Unit) 31, an engine 32, a starter 33, an alternator 34, a battery 35, an electric load 37, a current sensor 38, and the like.

[0023] The vehicle 3 is an automobile powered by an engine 32, and is provided with a starter 33 for cranking the engine 32 and an alternator 34 for generating electricity by the rotation of the engine 32. The vehicle 3 is also equipped with a battery 35. The battery 35 may be, for example, a lead-acid battery with a nominal voltage of 12 V. However, the battery 35 is not limited to a lead-acid battery.

[0024] When starting the engine 32, a voltage is applied to the starter 33 from a battery 35 via a power line 36. A flywheel is held by the crankshaft of the engine 32, and when a voltage is applied to the starter 33, a plunger of the starter 33 moves and a starter gear of the starter 33 meshes with the flywheel of the engine 32.

[0025] Furthermore, when a relay built into the starter 33 is turned on and the current supplied from the battery 35 to the starter 33 increases, the starter 33 inputs a large torque to the engine 32. The engine 32 is cranked by this torque. While being cranked, the engine 32 starts by firing an ignition plug of the engine 32.

[0026] The voltage of the battery 35 is applied to electrical loads 37 mounted on the vehicle 3, such as a wiper motor, headlights, an air conditioner, and audio equipment.

[0027] The alternator 34 includes a rotor, a stator, and an IC (Integral Circuit) regulator. The rotor rotates in conjunction with the rotation of the crankshaft of the engine 32. A field coil (rotor coil) is provided on the rotor. When a field current (excitation current) is supplied from the IC regulator to the field coil of the rotating rotor, three-phase AC current flows through the stator coil provided on the stator by electromagnetic induction. The three-phase AC current is rectified to DC voltage by a rectifier. The alternator 34 outputs DC power as generated power, and this generated power is supplied to the battery 35 via a power supply line 36, thereby charging the battery 35.

[0028] The ECU 31 provided in the vehicle 3 includes a microcontroller (microcomputer). The microcomputer includes, for example, a central processing unit (CPU) 31a and a memory 31b. The memory 31b includes a read-only memory (ROM), a random access memory (RAM), a data flash (flash memory), and the like. Although only one ECU 31 is shown in FIG. 2, the vehicle 3 is equipped with multiple ECUs having the same configuration as the ECU 31 to control each part. The multiple ECUs including the ECU 31 are connected to enable two-way communication using a controller area network (CAN) communication protocol.

[0029] A current sensor 38 is connected to the ECU 31 and is provided in association with the negative terminal of the battery 35. The current sensor 38 is capable of distinguishing between a charging current flowing through the negative terminal of the battery 35 and a discharging current flowing through the negative terminal of the battery 35. The terminal voltage (battery voltage) of the battery 35 is also input to the ECU 31. Furthermore, various sensors such as an accelerator sensor, an engine rotation sensor, and a throttle opening sensor are connected to the ECU 31, although these are not shown.

[0030] Here, the accelerator sensor is a sensor that outputs a detection signal corresponding to the amount of operation of the accelerator pedal. The engine rotation sensor is a sensor that outputs a detection signal in the form of a pulse signal synchronized with the rotation of the crankshaft of the engine 32. The throttle opening sensor is a sensor that outputs a detection signal corresponding to the opening of the electronic throttle valve (throttle opening) of the engine 32.

[0031] The ECU 31 controls the electronic throttle valve, injectors, spark plugs, starter 33, etc. of the engine 32 based on information acquired from detection signals of various sensors and various information input from other ECUs, etc. In this way, the ECU 31 starts, stops, adjusts the output, etc. of the engine 32.

[0032] Furthermore, the ECU 31 acquires the current values of the charging current and discharging current based on the detection signal of the current sensor 38. Next, the ECU 31 calculates the charge amount and discharge amount of the battery 35 by integrating the respective current values of the acquired charging current and discharging current. Furthermore, the ECU 31 calculates the remaining battery capacity, which is the remaining charge amount of the battery 35, by integrating the charge amount and discharge amount.

[0033] The ECU 31 controls power generation by the alternator 34 based on the remaining battery charge. When the ECU 31 calculates the remaining battery charge, the calculated remaining battery charge is updated and stored in the memory 31b. Furthermore, the ECU 31 calculates a State Of Charge (SOC) that indicates the ratio of the remaining battery charge to the charge capacity of the battery 35.

[0034] 3 is a diagram illustrating an example of the change over time in the voltage of the battery 35 when the vehicle engine 32 is started using the vehicle battery deterioration determination system according to this embodiment. In FIG. 3, the vertical axis represents the voltage of the battery 35, and the horizontal axis represents time. Here, an example of the change over time in the voltage of the battery 35 when the engine 32 is started will be described using FIG. 3.

[0035] When starting the engine 32, the ECU 31 outputs a starter signal (from off to on) that turns on a starter relay provided on the power supply path of the starter 33, and voltage is applied from the battery 35 to the starter 33. When the plunger of the starter 33 moves and a relay built into the starter 33 turns on, the current supplied from the battery 35 to the starter 33 increases, causing the battery voltage of the battery 35 to drop sharply (time T1). Thereafter, the battery voltage begins to rise and repeatedly fluctuates up and down while the engine 32 is being cranked by the torque from the starter 33.

[0036] In this embodiment, the ECU 31 acquires the minimum value VBSTA of the battery voltage during a predetermined period after the starter 33 is started, for example, from the output of the starter signal until the battery voltage begins to fluctuate due to cranking of the engine 32, for use in the deterioration determination process of the battery 35 described later.

[0037] In this embodiment, the ECU 31 acquires the minimum value VBSTA every time the engine 32 is started. Then, the ECU 31 compares the acquired minimum value VBSTA with a first determination threshold V1 used in a first intermediate deterioration determination process for the battery 35 and a second determination threshold V2 used in a second intermediate deterioration determination process for the battery 35. Details of the first intermediate deterioration determination process and the second intermediate deterioration determination process will be described later.

[0038] Returning to FIG. 2, the data management server 2 includes a CPU 21, a ROM 22, a RAM 24, a HDD (Hard Disk Drive) 25, a communication I / F (Interface) 26, and the like.

[0039] The communication I / F 26 controls communication with external devices such as the vehicle 3, the dealer terminal 4, and the user terminal 5 via the network NT. The HDD 25 is an example of a storage medium that stores various programs and various data.

[0040] The ROM 22 is an example of a storage medium that stores various programs. The RAM 24 functions as a work area when the CPU 21 executes the various programs. The CPU 21 is an example of a processor, and executes various processes such as determining deterioration of the battery 35 of the vehicle 3 and changing a threshold value used for determining deterioration of the battery 35.

[0041] 4 is a diagram showing an example of the functional configuration of the vehicle and the data management server of the vehicle battery degradation determination system according to this embodiment. Next, an example of the functional configuration of the data management server 2 and the vehicle 3 of the vehicle battery degradation determination system 1 according to this embodiment will be described with reference to FIG.

[0042] In this embodiment, the vehicle 3 realizes the communication unit 301 by the CPU 31a executing various programs stored in the memory 31b, etc. In this embodiment, the vehicle 3 realizes various functional units such as the communication unit 301 by the CPU 31a executing various programs, but this is not limited to this, and the various functional units can also be realized by hardware.

[0043] The communication unit 301 transmits vehicle information to the data management server 2 via the network NT. Here, the vehicle information includes the battery voltage of the battery 35, the current value of the current flowing through the battery 35, the temperature of the battery 35 (for example, the temperature of the battery fluid of the battery 35), the SOC (State Of Charge) of the battery 35, the starting state of the engine 32 of the vehicle 3, the starting state of the ECU 31, etc.

[0044] Furthermore, when determining the deterioration of the battery 35 in the vehicle 3, the communication unit 301 receives a threshold value from the data management server 2. In this case, the vehicle 3 can also determine the deterioration of the battery 35 using the received threshold value.

[0045] In this embodiment, the data management server 2 realizes a communication unit 311, an estimation unit 312, an acquisition unit 313, a calculation unit 314, a judgment unit 315, a selection unit 316, and a change unit 317 by the CPU 21 using the RAM 24 as a working area and executing various programs stored in the ROM 22, the HDD 25, etc.

[0046] In this embodiment, the data management server 2 realizes various functional units such as a communication unit 311, an estimation unit 312, an acquisition unit 313, a calculation unit 314, a judgment unit 315, a selection unit 316, and a modification unit 317 by having the CPU 21 execute various programs, but this is not limited to this, and it is also possible to realize these various functional units using hardware.

[0047] The communication unit 311 receives vehicle information from vehicles 3 on the market via the communication I / F 26. The communication unit 311 also transmits a deterioration determination result of the battery 35 to the dealer terminal 4 or the user terminal 5 via the communication I / F 26. Furthermore, when determining deterioration of the battery 35 within the vehicle 3, the communication unit 311 may transmit a threshold value used for determining deterioration of the battery 35 to the vehicle 3.

[0048] The estimation unit 312 acquires the battery voltage and current values during cranking of the engine 32 from the battery voltage of the battery 35 and the current value of the discharge current flowing to the negative terminal of the battery 35, which are included in the received vehicle information. Then, the estimation unit 312 applies a Kalman filter to the acquired battery voltage and current values, etc., to estimate the internal resistance, which is an example of an internal parameter of the battery 35.

[0049] Furthermore, the estimation unit 312 estimates an OCV (Open Circuit Voltage) of the battery 35 based on the battery voltage of the battery 35. In this embodiment, the estimation unit 312 estimates the battery voltage when the engine 32 is not started as the OCV.

[0050] The acquisition unit 313 acquires battery information used to determine deterioration of the battery 35. In this embodiment, the acquisition unit 313 acquires, as battery information, the internal resistance and OCV estimated by the estimation unit 312, the SOC included in the vehicle information, the temperature, etc. Then, the acquisition unit 313 stores big data that aggregates the battery information of vehicles 3 on the market in a database realized by a storage device such as the HDD 25.

[0051] The calculation unit 314 calculates the degradation level, which is the degree of degradation of the battery 35, based on the battery information stored in the HDD 25. In this embodiment, the calculation unit 314 calculates the degradation level of the battery 35 based on battery information (e.g., internal resistance, OCV, SOC, temperature) of the vehicle 3 for which degradation determination of the battery 35 is performed. Here, the internal resistance and OCV of the battery 35 vary depending on the SOC and temperature of the battery 35, etc. For example, the internal resistance of the battery 35 tends to increase as the temperature at which the SOC is 100% decreases. Therefore, in this embodiment, the data management server 2 stores a degradation level table that associates, for each combination of the SOC and temperature of the battery 35, the internal resistance and OCV with the degradation level of the battery 35 corresponding to the internal resistance and OCV. Then, the calculation unit 314 calculates, as the degradation level of the battery 35, the degradation level associated with the internal resistance and OCV acquired by the acquisition unit 313 in the degradation level table corresponding to the combination of SOC and temperature acquired by the acquisition unit 313.

[0052] The determination unit 315 determines the deterioration of the battery 35 based on whether the deterioration level calculated by the calculation unit 314 exceeds a preset threshold. In this embodiment, the determination unit 315 determines the deterioration of the battery 35 every time the engine 32 starts. Then, when the deterioration level of the battery 35 exceeds the threshold a preset number of times (for example, five times) consecutively, the determination unit 315 determines that the battery 35 is deteriorated.

[0053] Furthermore, the determination unit 315 sets the internal resistance and OCV of the battery 35 when the engine 32 is started for the first time after the battery 35 is installed in the vehicle 3 as the initial values of the internal resistance and OCV of the battery 35 when the SOH (State Of Health) of the battery 35 is 100%. Then, the determination unit 315 determines that the battery 35 has deteriorated if the difference between the latest values and the initial values, which are the internal resistance and OCV of the battery 35 at an initial time (for example, a predetermined period after the battery 35 is installed in the vehicle 3), is equal to or greater than a predetermined value. Here, the latest values are the internal resistance and OCV estimated in the most recent trip. Furthermore, the trip refers to the time from when the ignition was turned on (when the engine 32 was started).

[0054] Furthermore, the determination unit 315 executes a first intermediate deterioration determination process and a second intermediate deterioration determination process for the battery 35 based on the battery voltage of the battery 35 when the engine 32 is started.

[0055] The first intermediate degradation determination process determines whether the minimum value VBSTA of the battery voltage is equal to or less than a first determination threshold V1, and counts the number of times the minimum value VBSTA is equal to or less than the first determination threshold V1 (hereinafter referred to as the first intermediate degradation determination count). The first determination threshold V1 is a battery voltage threshold at which it is determined that the battery 35 is degraded.

[0056] The second intermediate degradation determination process determines whether the minimum battery voltage VBSTA is equal to or less than a second determination threshold V2, and counts the number of times the minimum battery voltage VBSTA is equal to or less than the second determination threshold V2 (hereinafter referred to as the second intermediate degradation determination count). The second determination threshold V2 is a battery voltage threshold at which use of the battery 35 is stopped.

[0057] The selection unit 316 selects an offset value associated with the established use condition of the battery 35 from an offset value table that associates each of a plurality of use conditions of the battery 35 with an offset value used to change the threshold. The change unit 317 changes the threshold based on the selected offset value. This changes the threshold used to determine the deterioration of the battery 35 in accordance with the use condition of the battery 35 of each vehicle 3, making it possible to prevent the deterioration of the battery 35 from being determined even when the battery 35 is not deteriorated. As a result, the determination unit 315 can determine the deterioration of the battery 35 with high accuracy.

[0058] Here, the usage conditions of the battery 35 include, for example, the mileage of the vehicle 3, the electrical load frequency, the battery usage age, the first intermediate deterioration determination count, the second intermediate deterioration determination count, the number of days the vehicle has been left unattended, and the battery temperature. The electrical load frequency is the average frequency of application of battery voltage to the electrical load 37 per day over a preset number of days of use (for example, 50 days). The battery usage age is the number of years the battery 35 has been in use. The number of days the vehicle has been left unattended is the number of days the vehicle 3 has been left unattended without being used. The battery temperature is the temperature of the battery 35 when the vehicle 3 is in use.

[0059] Here, the use conditions are the use conditions of the battery 35 for which the threshold is changed. For example, the use conditions may be the use conditions (1) to (7) shown in Table 1 below. [Table 1]

[0060] Usage condition (1) is that the mileage of vehicle 3 is 50,000 km or more. Usage condition (2) is that the electrical load frequency is 60% / 50 days or more. Usage condition (3) is that the battery has been in use for 5 years or more.

[0061] Furthermore, usage condition (4) is that the first intermediate deterioration determination count is 100 or more. Furthermore, usage condition (5) is that the second intermediate deterioration determination count is 80 or more. In other words, the multiple usage conditions may include gradual usage conditions for the battery 35. This makes it possible to prevent frequent determinations of deterioration of the battery 35. Furthermore, usage condition (6) is that the number of days the vehicle has been left unattended is 30 or more. Usage condition (7) is that the battery temperature is 30°C or higher.

[0062] Here, the offset value table is correspondence information that associates each of a plurality of use conditions with an offset value used to change the threshold value. In this embodiment, the offset value table is a table that associates use conditions (1) to (7) with the internal resistance of the battery 35 and the offset value of the OCV, as shown in Table 2 below. [Table 2]

[0063] In this embodiment, the change unit 317 offsets the battery information (for example, at least one of the internal resistance and the OCV) acquired by the acquisition unit 313 based on the offset value selected by the selection unit 316, and changes the threshold value based on the offset battery information. Alternatively, the change unit 317 may offset the battery information based on a value obtained by integrating the offset value associated with the established use condition, and change the threshold value based on the offset battery information.

[0064] In this embodiment, the offset value may be a value set in stages. The offset value may also be different for each attribute, such as the grade and model of the vehicle 3. The offset value may also be set based on big data of the attributes of the vehicle 3 for which the threshold is to be changed, among the big data stored in a storage device such as the HDD 25.

[0065] This allows the threshold to be changed to reflect the deterioration trends of the batteries 35 of vehicles 3 in the market. Also, since it becomes easier to collect battery information used to change the threshold, the development man-hours required to change the threshold can be reduced. Furthermore, by changing the threshold in the data management server 2, it becomes unnecessary to change the threshold in each vehicle 3, and therefore the efficiency of changing the threshold can be improved. Furthermore, the offset value may be changeable as needed depending on the usage status of the battery 35.

[0066] In this embodiment, the selection unit 316 and the change unit 317 are provided in the data management server 2, which is an example of a server. This eliminates the need to change the threshold for each vehicle 3 in the market for each vehicle, making it easier to change the threshold. In this case, when determining the deterioration of the battery 35 in each vehicle 3, the vehicle 3 downloads the changed threshold from the data management server 2 and uses the downloaded threshold to determine the deterioration of the battery 35. The selection unit 316 and the change unit 317 may also be provided in the vehicle 3. This makes it possible to change the threshold without using the data management server 2.

[0067] 5 is a flowchart showing an example of the flow of the battery deterioration determination process in the vehicle battery deterioration determination system according to this embodiment. Next, an example of the flow of the deterioration determination process for the battery 35 in the vehicle battery deterioration determination system 1 according to this embodiment will be described with reference to FIG.

[0068] The estimation unit 312 determines whether the engine 32 is started or not (step S501) based on the start state of the engine 32 indicated by the vehicle information received by the communication unit 311. If the engine 32 is not started (step S501: No), the estimation unit 312 determines whether the ECU 31 is activated or not (step S502).

[0069] Next, the estimation unit 312 determines whether a predetermined time (e.g., six hours) has elapsed since the engine 32 was not started and the ECU 31 was activated (step S503). If the predetermined time has not elapsed since the engine 32 was not started and the ECU 31 was activated (step S503: No), the estimation unit 312 returns to step S503.

[0070] On the other hand, if the engine 32 has not started and a predetermined time has elapsed since the ECU 31 was activated (step S503: Yes), the estimation unit 312 determines that the OCV of the battery 35 has stabilized, and estimates the OCV of the battery 35 based on the battery voltage included in the received vehicle information (step S504).The estimation unit 312 then stores the estimated OCV in a storage device such as the HDD 25 (step S505).

[0071] Furthermore, if the engine 32 has started (step S501: Yes), the estimation unit 312 determines whether or not this is the first start of the engine 32 during one trip of the vehicle 3 (step S506). If this is the second or subsequent start of the engine 32 during one trip of the vehicle 3 (step S506: No), the CPU 21 does not determine whether the battery 35 has deteriorated, and ends the deterioration determination process for the battery 35.

[0072] On the other hand, if this is the first start of the engine 32 during one trip of the vehicle 3 (step S506: Yes), the estimation unit 312 acquires the battery voltage and current values of the battery 35 at the time of cranking the engine 32 from the battery voltage and the current value of the discharge current of the battery 35 included in the received vehicle information (step S507). Next, the estimation unit 312 applies a Kalman filter to the acquired battery voltage, current value, etc., to estimate the internal resistance of the battery 35 (step S508).

[0073] The acquisition unit 313 acquires battery information including the internal resistance and OCV estimated by the estimation unit 312, and the SOC, temperature, etc. included in the vehicle information received from the vehicle 3, and stores (preserves) the acquired battery information in a database such as the HDD 25 (step S509). Then, the calculation unit 314 calculates the deterioration level of the battery 35 based on the internal resistance, OCV, SOC, temperature, etc. included in the acquired battery information (step S510).

[0074] Next, the determination unit 315 determines whether the calculated deterioration level exceeds a threshold value (step S511). If the calculated deterioration level exceeds the threshold value (step S511: Yes), the determination unit 315 increments the battery deterioration count number n by 1 (step S512). Furthermore, the determination unit 315 determines whether the count number n is equal to or greater than a preset count number (e.g., 5 times) (step S513). If the count number n is less than the preset count number (step S513: No), the determination unit 315 determines that the battery 35 is not deteriorated.

[0075] On the other hand, if the count number n is equal to or greater than the preset count number (step S513: Yes), the determination unit 315 determines that the battery 35 is degraded. The internal resistance of the battery 35 varies depending on the OCV, temperature, SOC, etc. of the battery 35, which causes variations in the calculation result of the degradation level. Therefore, in this embodiment, the determination unit 315 determines that the battery 35 is degraded if the count number of the degradation level of the battery 35 is equal to or greater than a preset threshold value consecutively. This improves the accuracy of determining the degradation of the battery 35. Then, the communication unit 311 notifies the dealer terminal 4 of the degradation determination result of the battery 35 via the communication I / F 26 (step S514).

[0076] In conventional vehicle battery deterioration determination systems, deterioration of the battery 35 can only be detected when the vehicle 3 is inspected, and it is not possible to detect deterioration of the battery 35 of the vehicle 3 without waiting for the inspection. However, according to the vehicle battery deterioration determination system 1 of this embodiment, it is possible to determine deterioration of the battery 35 when the engine 32 of the vehicle 3 is started. As a result, even if the battery 35 has deteriorated before the vehicle 3 is inspected, it is possible to realize driving that makes the most of the performance of the battery 35.

[0077] If the calculated deterioration level does not exceed the threshold value (step S511: No), the determination unit 315 determines that the battery 35 has not deteriorated, and resets the count number n (step S515).

[0078] 6 is a flowchart showing an example of the flow of the degradation determination process at the start of use of the battery in the vehicle battery degradation determination system according to this embodiment. Next, an example of the flow of the degradation determination process at the start of use of the battery 35 in the vehicle battery degradation determination system 1 according to this embodiment will be described with reference to FIG.

[0079] First, the determination unit 315 determines whether or not this is the first start of the engine 32 after the battery 35 is installed in the vehicle 3 (step S601). If this is the first start of the engine 32 after the battery 35 is installed in the vehicle 3 (step S601: Yes), the determination unit 315 sets the internal resistance and OCV of the battery 35 when the engine 32 is started for the first time after the battery 35 is installed in the vehicle 3 to the initial values of the internal resistance and OCV of the battery 35 when the SOH of the battery 35 is 100% (step S602).

[0080] On the other hand, if this is not the first time the engine 32 has been started since the battery 35 was installed in the vehicle 3 (step S601: No), the determination unit 315 calculates difference values between the latest values and the initial values of the internal resistance and OCV of the battery 35 (step S603). Here, the latest values are the internal resistance and OCV estimated in the most recent trip. In this embodiment, the latest values are battery information stored in a database such as the HDD 25 in S509 of FIG. 5. As described above, the trip indicates the time from when the ignition was turned on (start of the engine 32). Then, the determination unit 315 determines whether the calculated difference value is equal to or greater than a preset value (step S604). If the calculated difference value is equal to or greater than the preset value (step S604: Yes), the determination unit 315 determines that the battery 35 has deteriorated. On the other hand, if the calculated difference value is less than the preset value (step S604: No), the determination unit 315 determines that the battery 35 has not deteriorated.

[0081] 7 is a flowchart showing an example of the flow of the offset value setting process in the vehicle battery deterioration determination system 1 according to this embodiment. Next, an example of the flow of the offset value setting process in the vehicle battery deterioration determination system 1 according to this embodiment will be described with reference to FIG.

[0082] The change unit 317 acquires battery information such as the internal resistance, OCV, SOC, and temperature of the battery 35 of a vehicle 3 on the market (step S701). Furthermore, the change unit 317 acquires battery information of the battery 35 of a vehicle 3 whose battery 35 has actually deteriorated (step S702).

[0083] Then, the change unit 317 sets an offset value associated with each use condition in the offset value table based on the battery information of the battery 35 of the vehicle 3 on the market and the battery information of the deteriorated battery 35 (step S703).

[0084] 8 is a flowchart showing an example of the flow of the threshold value changing process in the vehicle battery deterioration determination system 1 according to this embodiment. Next, an example of the flow of the threshold value changing process in the vehicle battery deterioration determination system 1 according to this embodiment will be described with reference to FIG.

[0085] First, the selection unit 316 determines whether or not at least one of the plurality of use conditions of the battery 35 of the vehicle 3 is satisfied (step S801). If none of the plurality of use conditions of the battery 35 is satisfied (step S801: No), the change unit 317 does not change the threshold value.

[0086] On the other hand, if at least one of the multiple usage conditions of the battery 35 is met (step S801: Yes), the selection unit 316 changes the threshold value based on the offset values of the internal resistance and OCV associated with the met usage condition in the offset value table (step S802).

[0087] Fig. 9 is a diagram for explaining an example of the battery degradation determination process in the vehicle battery degradation determination system according to this embodiment. In Fig. 9, the vertical axis represents the internal resistance of the battery 35, and the horizontal axis represents time. Next, an example of the threshold value change process in the vehicle battery degradation determination system 1 according to this embodiment will be described with reference to Fig. 9.

[0088] For example, as shown in Fig. 9, if the degradation level based on the internal resistance of the battery 35 is equal to or greater than the threshold value five times consecutively from time t1 to time t5, the determination unit 315 determines that the battery 35 is degraded. Also, as shown in Fig. 9, if the use condition (4) of the battery 35 is met at time t-2, the change unit 317 offsets the internal resistance based on the offset value associated with the use condition (4) in the offset value table, and changes the threshold value based on the offset internal resistance.

[0089] Also, as shown in FIG. 9, when the usage condition (5) of the battery 35 is satisfied at time t-1, the change unit 317 offsets the internal resistance based on the offset value associated with the usage condition (5) in the offset value table, and changes the threshold value based on the offset internal resistance.

[0090] As described above, the vehicle battery deterioration determination system 1 according to this embodiment selects an offset value associated with the established usage conditions of the battery 35 from the offset value table, and changes the threshold value based on the selected offset value, thereby changing the threshold value used to determine the deterioration of the battery 35 in accordance with the usage conditions of the battery 35 of each vehicle 3, thereby preventing the battery 35 from being determined to be deteriorated even when it is not. As a result, it becomes possible to determine the deterioration of the battery 35 with high accuracy.

[0091] Furthermore, according to the vehicle battery degradation determination system 1 of this embodiment, by setting multiple usage conditions as tiered usage conditions for the battery 35, it is possible to prevent frequent determinations of battery 35 degradation. Furthermore, according to the vehicle battery degradation determination system 1 of this embodiment, by providing the selection unit 316 and the change unit 317 in the data management server 2, it is no longer necessary to change the threshold for each vehicle 3 on the market, making it possible to easily change the threshold. Furthermore, according to the vehicle battery degradation determination system 1 of this embodiment, by providing the selection unit 316 and the change unit 317 in the vehicle 3, it is possible to change the threshold without using the data management server 2. [Explanation of symbols]

[0092] 1. Vehicle battery deterioration determination system 2 Data management server 3 vehicles 4 Dealer terminals 5. User terminal 21,31a CPU 22 ROM 24 RAM 25 HDD 26 Communication I / F 31 ECU 31b memory 32 Engine 33 Starter 34 Alternator 35 Battery 36 Power Line 37 Electrical Load 38 Current Sensor 301,311 Communications Department 312 Estimation Department 313 Acquisition Department 314 Calculation Unit 315 Judgment section 316 Selection Section 317 Changes NT Network

Claims

1. an acquisition unit that acquires battery information used to determine deterioration of a battery mounted on a vehicle; a calculation unit that calculates a deterioration level of the battery based on the battery information; a determination unit that determines deterioration of the battery based on whether the deterioration level exceeds a threshold; a selector that selects an offset value associated with a use condition that is established in correspondence information that associates each of a plurality of use conditions of the battery with an offset value used to change the threshold; a change unit that offsets the battery information based on a value obtained by integrating the offset value selected by the selection unit, and changes the threshold value based on the offset battery information; Equipped with the plurality of usage conditions include at least two of a mileage of the vehicle, a frequency of electrical loads on the battery, an age of the battery, a first number of intermediate deterioration determinations, a second number of intermediate deterioration determinations, a number of days the vehicle has been left unused, and a temperature of the battery; the first intermediate deterioration determination count is the number of times that the voltage of the battery becomes equal to or lower than a first determination threshold voltage for determining that the battery is deteriorated during a predetermined period after a starter of the vehicle is started, The second intermediate deterioration determination count is the number of times that the voltage of the battery during a predetermined period after the starter of the vehicle is started falls below a second determination threshold that is less than the first determination threshold.

2. The vehicle battery deterioration determination device according to claim 1 , wherein the selection unit and the change unit are provided in the vehicle or a server.

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