CN105270183B - The control device and control method of secondary cell - Google Patents

Abstract

The present invention provides a control device and control method for a secondary battery. The control circuit includes a calculation unit, a determination unit, a display control unit, a power limiting unit, and a start prohibition unit. The calculation unit converts each parameter calculated according to the factor of aging (lithium deposition) of the lithium-ion battery into the age of the battery. The determination unit determines that battery diagnosis is necessary when at least one of the battery ages has reached the upper limit age. When it is determined that the battery diagnosis is necessary, the display control unit displays a diagnosis request message on the display device to urge the user to perform the battery diagnosis. The electric power limiting unit limits the charging and discharging electric power of the storage battery when the result of the battery diagnosis has not been received after the display of the diagnosis request message has started. The start prohibition unit prohibits start of the drive system of the vehicle when the result of the battery diagnosis has not been received after the charge and discharge electric power of the battery is limited.

Description

Secondary battery control device and control method

This application is a divisional application of the application filed on November 14, 2012 with the application number 201080066787.1 and the title of the invention is "Control Device and Control Method for Secondary Battery".

technical field

The present invention relates to control of a secondary battery capable of diagnosing a state of degradation by a diagnostic device.

Background technique

In recent years, electric vehicles (hybrid vehicles, electric vehicles, etc.) that obtain driving force using electric power have attracted widespread attention. An electric vehicle generally includes a secondary battery that stores electric power for driving a motor. Secondary batteries are subject to aging, and failure will occur if they continue to be used in an aged state. Therefore, in an electric vehicle, it is important to grasp the degree of deterioration of the secondary battery. Regarding this point, for example, Japanese Patent Application Laid-Open No. 2007-74891 (Patent Document 1) discloses a technique of estimating the life of a battery from the usage history of the battery and warning the user.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2007-74891

Patent Document 2: Japanese Unexamined Patent Publication No. 2006-197765

Patent Document 3: Japanese Patent Laid-Open No. 2005-124353

Patent Document 4: Japanese Patent Laid-Open No. 2009-199936

Contents of the invention

However, even if the life of the battery is estimated and the user is warned as in Patent Document 1, if the user continues to use the secondary battery with a short service life, the secondary battery may fail.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to prevent secondary batteries from malfunctioning due to continued use in a degraded state.

The control device of the present invention is a control device for a secondary battery capable of diagnosing a state of degradation by a diagnostic device. The control device includes: a determination unit that determines whether a diagnosis is necessary based on the history of the usage status of the secondary battery; a warning unit that warns the user to accept the diagnosis when the determination unit determines that the diagnosis is necessary; If the diagnosis is not performed within a predetermined period after receiving the diagnosis, the output of the secondary battery is limited.

Preferably, the determination unit determines whether the diagnosis is necessary for each of a plurality of parameters including a service period of the secondary battery, an accumulated value of time when the voltage of the secondary battery exceeds a reference value, and the secondary battery. At least two values of an accumulated value of a part of the charge current of the battery exceeding a predetermined value and an accumulated value of a discharge current of the secondary battery.

Preferably, the determination unit calculates a battery age indicating a degree of deterioration of the secondary battery for each of the plurality of parameters, and determines that diagnosis is necessary when at least one of the calculated battery ages reaches an upper limit age.

Preferably, the control device further includes a changing unit that changes the age of the battery according to the result of the diagnosis when the diagnosis is performed.

Preferably, the changing unit returns the battery age that has reached the upper limit age to a predetermined age lower than the upper limit age when the result of the diagnosis indicates that the secondary battery can be used continuously.

Preferably, the changing unit returns the battery age that has reached the upper limit age to a predetermined age and sets the age of other batteries that have not reached the upper limit age to the predetermined age when the diagnosis result indicates that the secondary battery can be used continuously.

Preferably, when the result of the diagnosis indicates that the secondary battery can continue to be used, when at least one of the ages of the plurality of batteries is higher than a predetermined age, the changing unit sets the ages of the plurality of batteries as the predetermined age, When all battery ages are lower than the specified age, multiple battery ages will not be changed.

Preferably, the changing unit sets a plurality of battery ages as the upper limit age when the result of the diagnosis indicates that the secondary battery cannot be used any longer. The warning unit warns the user that the secondary battery cannot be used when the result of the diagnosis indicates that the secondary battery cannot be used any longer. The restriction unit prohibits charge and discharge of the secondary battery when the result of the diagnosis indicates that the secondary battery cannot be used any longer.

Preferably, the limiting unit executes at least one of first control for lowering the upper limit value of charging electric power and upper limit value of discharging electric power of the secondary battery and second control for prohibiting charge and discharge of the secondary battery. This limits the output of the secondary battery.

Preferably, the restricting unit executes the first control when the diagnosis has not been performed for a first period after the determination unit determines that the diagnosis is necessary, and when the diagnosis is not performed for a second period longer than the first period after the determination unit determines that the diagnosis is necessary. At the time of diagnosis, the second control is executed.

Preferably, the control device further includes: a display device for displaying information to a user; and a power control device for controlling charging and discharging power of the secondary battery. The warning unit warns the user to receive a diagnosis by displaying a message prompting the diagnosis on the display device. The limiting unit limits the output of the secondary battery by controlling the power control device.

Preferably, the determination unit determines whether the diagnosis is necessary based on at least one of the following parameters: the use period of the secondary battery, the cumulative value of the time when the voltage of the secondary battery exceeds a reference value, and the charging current of the secondary battery. The cumulative value of the part exceeding the predetermined value, and the cumulative value of the discharge current of the secondary battery.

A control method according to another aspect of the present invention is a control method performed by a secondary battery control device capable of diagnosing a state of degradation by a diagnostic device. The control method includes the steps of: judging whether a diagnosis is necessary based on the history of the usage status of the secondary battery; warning the user to accept the diagnosis when it is judged that the diagnosis is necessary; This is a procedure to limit the output of the secondary battery when the diagnosis is not performed.

Invention effect

According to the present invention, it is possible to warn the user that the diagnosis of the deterioration state of the secondary battery is required, thereby urging the user to perform the diagnosis by the diagnosis device. In addition, when the secondary battery is continued to be used without receiving the diagnosis after the warning is issued, the use of the secondary battery is restricted (restricted or prohibited). Therefore, it is possible to avoid failure of the secondary battery due to continued use in a degraded state.

Description of drawings

FIG. 1 is a block diagram illustrating a schematic configuration of a vehicle.

FIG. 2 is a diagram showing the configuration of a storage battery and a monitoring unit.

FIG. 3 is a diagram showing the logic of deposition of metallic lithium in a storage battery.

FIG. 4 is a graph showing the relationship between the lithium deposition amount and the failure initiation temperature of the storage battery.

Fig. 5 is a functional block diagram of a control circuit.

FIG. 6 is a map showing the relationship between the battery usage period Pb and the storage battery age YP.

FIG. 7 is a diagram showing a method of calculating the cell voltage exceeding time Tv.

FIG. 8 is a map showing the relationship between cell voltage excess time Tv and battery age YV.

FIG. 9 is a diagram illustrating a calculation method of the integrated overcurrent value SIin.

FIG. 10 is a map showing the relationship between overcurrent integrated value SIin and battery age Yiin.

FIG. 11 is a diagram showing a calculation method of the integrated discharge current value SIout.

FIG. 12 is a map showing the relationship between discharge current integrated value SIout and battery age Yiout.

FIG. 13 is a diagram illustrating a method of determining whether battery diagnosis is necessary.

FIG. 14 is a diagram (Part 1) showing a method of updating the battery age Y. FIG.

Fig. 15 is a diagram (part 2) showing a method of updating the battery age Y.

FIG. 16 is a diagram (part 3) showing a method of updating the battery age Y. FIG.

Fig. 17 is a flowchart (Part 1) showing the processing procedure of the control circuit.

Fig. 18 is a flowchart (Part 2) showing the processing procedure of the control circuit.

FIG. 19 is a diagram illustrating a flow of behavior of the vehicle controlled by the control circuit.

detailed description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that, below, the same reference numerals are attached to the same or corresponding parts in the drawings, and the description thereof will not be repeated in principle.

FIG. 1 is a block diagram illustrating a schematic configuration of a vehicle 5 to which a secondary battery control device according to an embodiment of the present invention is applied. It should be noted that the vehicle 5 shown in FIG. 1 is a hybrid vehicle, but the present invention is not limited to a hybrid vehicle, and is applicable to all electric vehicles.

1, vehicle 5 includes battery 10, system main relays 22, 24, power control unit (Power Control Unit, hereinafter referred to as "PCU") 30, motor generators 41, 42, engine 50, power split mechanism 60, drive shaft 70, and wheel 80.

The storage battery 10 is a battery pack in which a plurality of lithium ion secondary battery cells are connected in series. Battery 10 may also be configured to be chargeable by an external power supply of vehicle 5 . It should be noted that the present invention is not limited to lithium ion secondary batteries, but can be applied to all secondary batteries that require grasping of the state of aging.

The engine 50 outputs kinetic energy using combustion energy of fuel. Power split mechanism 60 is connected to output shafts of motor generators 41 , 42 and engine 50 , and drives drive shaft 70 by the output of motor generators 42 and/or engine 50 . Furthermore, the wheels 80 are rotated by the drive shaft 70 . In this way, the vehicle 5 runs with the output of the engine 50 and/or the motor generator 42 .

The motor generators 41 and 42 can function as both generators and motors, but the motor generator 41 mainly operates as a generator, and the motor generator 42 mainly operates as a motor.

Specifically, the motor generator 41 is used as a starter for starting the engine 50 when an engine start is requested during acceleration or the like. At this time, motor generator 41 receives electric power supply from battery 10 via PCU 30 and is driven as an electric motor to start the engine. Further, after the engine 50 is started, the motor generator 41 is rotated by the engine output transmitted through the power split mechanism 60 to generate electricity.

Motor generator 42 is driven by at least one of the electric power stored in battery 10 and the electric power generated by motor generator 41 . The driving force of the motor generator 42 is transmitted to the drive shaft 70 . Thereby, the motor generator 42 assists the engine 50 to run the vehicle 5 , or drives the vehicle 5 only by its own driving force.

In addition, during regenerative braking of the vehicle 5 , the motor generator 42 operates as a generator by utilizing the fact that it is driven by the rotational force of the wheels. At this time, the regenerative electric power generated by motor generator 42 charges battery 10 via PCU 30 .

The PCU 30 performs bidirectional power conversion between the battery 10 and the motor generators 41 and 42, and controls the motor generators 41 and 42 so that they operate according to their respective operation command values (typically torque command values). power conversion. For example, PCU 30 includes an inverter for converting DC power from battery 10 into AC power and applying it to motor generators 41 and 42 . The inverter can also convert the regenerative power generated by the motor generators 41 and 42 into DC power to charge the battery 10 .

System main relays 22 and 24 are provided between PCU 30 and battery 10 . The system main relays 22 and 24 are turned on and off according to a relay control signal SE. When the system main relays 22 and 24 are cut off (opened), the charging and discharging path of the storage battery 10 is mechanically blocked.

Vehicle 5 further includes a monitoring unit 20 for monitoring battery 10 , a control circuit 100 , and a display device 200 .

The monitoring device 20 outputs a value indicating the state of the battery 10 to the control circuit 100 based on the outputs of the temperature sensor 12 , the voltage sensor 14 , and the current sensor 16 provided on the battery 10 . As will be described later, an overvoltage detection means is incorporated in the monitoring unit 20 , and the output of the overvoltage detection means is also output to the control circuit 100 .

In addition, in FIG. 1, the temperature sensor 12 and the voltage sensor 14 are shown collectively, respectively. That is, in practice, a plurality of temperature sensors 12 and voltage sensors 14 are provided. Furthermore, a plurality of current sensors 16 may also be provided.

The control circuit 100 is composed of an electronic control unit (ECU: Electronic Control Unit) incorporating a CPU (Central Processing Unit) (not shown) and a memory, and executes predetermined arithmetic processing based on information stored in the memory. The memory includes EEPROM (Electrically Erasable Programmable Read Only Memory) whose contents can be rewritten electrically.

The control circuit 100 sets torque request values for the motor generators 41 and 42 based on the user's accelerator operation amount and vehicle speed. Control circuit 100 controls power conversion by PCU 30 so that motor generators 41 and 42 operate in accordance with the torque demand value. At this time, the control circuit 100 controls the PCU 30 so that the power charged to the battery 10 does not exceed the charging power upper limit value Win, and the power discharged from the battery 10 does not exceed the discharge power upper limit value Wout.

It should be noted that the engine 50 is controlled by another ECU not shown. Furthermore, in FIG. 1 , the control circuit 100 is described as a single unit, but it may be divided into two or more different units.

The display device 200 displays various messages to the user in accordance with control signals from the control circuit 100 . The message displayed on the display device 200 includes a message (hereinafter referred to as "diagnosis request") requesting the user to accept a diagnosis of the deterioration state of the storage battery 10 (hereinafter referred to as "battery diagnosis") by the diagnosis device 300 described later. message"), and a message notifying the user that the storage battery 10 cannot be used (hereinafter referred to as "unusable message").

Furthermore, vehicle 5 is configured to be connectable to diagnostic device 300 . Hereinafter, a case where diagnostic device 300 is installed in a repair shop installed at a dealer or the like will be described. It should be noted that the diagnostic device 300 is not necessarily limited to being installed outside the vehicle 5 , and the diagnostic device 300 may also be installed inside the vehicle 5 . When the diagnostic device 300 is installed inside the vehicle 5 , for example, the diagnostic device 300 may perform a battery diagnosis in accordance with an instruction from a user while the vehicle is stopped.

When the diagnostic device 300 is connected to the vehicle 5, communication between the diagnostic device 300 and the control circuit 100 becomes possible.

Diagnosis device 300 is operated by maintenance personnel working in a repair shop or the like. Diagnosis device 300 communicates with control circuit 100 to perform the battery diagnosis described above. In the battery diagnosis, the lithium deposition amount of the storage battery 10 is measured based on the voltage drop of the storage battery 10 during discharge. In addition, the diagnosis device 300 diagnoses whether the storage battery 10 is "continuously usable", "unusable", or "new product state" (replaced to a new product state or in the same state as a new product) based on the measured amount of lithium deposition. ).

The diagnostic device 300 sends a signal R1 to the control circuit 100 when the diagnostic result is "can continue to be used", and sends a signal R2 to the control circuit 100 when the diagnostic result is "cannot continue to be used". ”, the signal R3 is sent to the control circuit 100.

FIG. 2 is a diagram showing the configuration of the storage battery 10 and the monitoring unit 20 .

The storage battery 10 is composed of a plurality of battery blocks 11 . In addition, each battery block 11 is configured by connecting N (N is an integer equal to or greater than 2) battery cells 10 # in series. It should be noted that the configuration when N=7 is illustrated in FIG. 2 .

A plurality of voltage sensors 14 are provided for each battery block 11 to detect the output voltage of each battery block 11 .

The monitoring unit 20 includes: a plurality of voltage comparison circuits 20a provided corresponding to each battery cell 10# inside the battery block 11; an overvoltage detection circuit 20b connected to each voltage comparison circuit 20a; and an IG shutoff counter 20c. The voltage comparison circuit 20 a and the overvoltage detection circuit 20 b shown in FIG. 2 are provided for each battery block 11 . It should be noted that the overvoltage detection circuit 20 b may also be provided inside the control circuit 100 .

Each voltage comparator circuit 20a compares the voltage across both ends of the corresponding battery cell 10# (single cell voltage) with a judgment voltage V1 (for example, 4.05 volts) for judging overvoltage, and when the cell voltage exceeds the judgment voltage V1 , the signal S1 is output to the overvoltage detection circuit 20b. Similarly, each voltage comparison circuit 20a compares the corresponding cell voltage with a determination voltage V2 (for example, 4.25 volts), and outputs a signal S2 to the overvoltage detection circuit 20b when the cell voltage exceeds the determination voltage V2.

The overvoltage detection circuit 20 b outputs the overvoltage detection signal F1 to the control circuit 100 when receiving the signal S1 from at least one of the voltage comparison circuits 20 a. Similarly, the overvoltage detection circuit 20b outputs an overvoltage detection signal F2 to the control circuit 100 when receiving the signal S2 from at least one of the voltage comparison circuits 20a.

The IG off counter 20c counts the elapsed time (hereinafter, referred to as "IG off time Tigoff") after a switch for instructing start/stop of the drive system of the vehicle 5 (hereinafter, referred to as "IG switch") is turned off. and store. It should be noted that the IG cut-off counter 20c counts three types of IG cut-off time Tigoff each having a least significant bit (LSB: Least Significant Bit) of 1 minute, 1 hour, and 1 day. Then, the IG off-counter 20c outputs the stored IG off-time Tigoff to the control circuit 100 when the IG switch is turned on, and initializes (sets to zero) the stored IG off-time Tigoff.

However, when a lithium-ion secondary battery such as the storage battery 10 is used for a long period of time, metal lithium is deposited inside it, and failure may occur.

FIG. 3 is a diagram showing the deposition logic of metallic lithium in the storage battery 10 . As shown in FIG. 3 , when the battery 10 is continuously charged, the throttle is turned on/off, the wheels 80 slip/grip, etc., the voltage of each single cell of the battery 10 exceeds the judgment voltage, or the current exceeding the allowable value flows to the battery 10. The storage battery 10 is charged. This state is a factor, and metallic lithium is deposited inside the storage battery 10 .

FIG. 4 is a graph showing the relationship between the lithium deposition amount and the failure initiation temperature of the storage battery 10 . As shown in FIG. 4 , the failure initiation temperature of the storage battery 10 decreases as the lithium deposition amount increases. That is, the higher the amount of deposited lithium, the higher the possibility of failure of the storage battery 10 . When the storage battery 10 fails, electric power cannot be supplied to the motor generators 41 and 42, and the driving becomes substantially impossible.

In order to avoid such a situation, it is preferable to regularly receive battery diagnosis by the above-mentioned diagnosis device 300 to accurately grasp the state of lithium deposition, and to replace the storage battery 10 with a new one as necessary.

Therefore, the control circuit 100 of this embodiment estimates the amount of lithium deposition based on the history of the usage status of the storage battery 10, and when the estimated amount of lithium deposition reaches the upper limit, warns the user that a battery diagnosis is required to urge The user performs battery diagnosis. Then, when the battery diagnosis has not been performed for a predetermined period of time, the control circuit 100 limits (limits or prohibits) the use of the storage battery 10 .

FIG. 5 is a functional block diagram of a portion of the control circuit 100 associated with battery diagnostics. It should be noted that each functional block shown in FIG. 5 may be realized by hardware (electronic circuit, etc.), or may be realized by software processing (execution of a program, etc.).

The control circuit 100 includes a calculation unit 110 , a storage unit 120 , a determination unit 130 , a display control unit 140 , a power limiting unit 150 , and an activation prohibition unit 160 . In addition, the control circuit 100 includes a receiving unit 170 and an updating unit 180 .

The calculation unit 110 calculates the “battery age Y” based on the history of the usage status of the battery 10 . The battery age Y corresponds to the degree of deterioration of the battery 10 , that is, an estimated value of the lithium deposition amount, and is used for determining whether or not battery diagnosis is necessary.

The calculation unit 110 calculates four types of storage battery age Y according to the main cause of lithium deposition. The four battery ages Y are calculated by the first calculation unit 111 , the second calculation unit 112 , the third calculation unit 113 , and the fourth calculation unit 114 , respectively.

First, the first calculation unit 111 will be described. The first calculation unit 111 calculates the service period of the storage battery 10 (hereinafter referred to as “battery usage period”) based on the above-mentioned IG off time Tigoff and the elapsed time from when the IG was turned on (hereinafter referred to as “IG on time Tigon”). Period Pb") is stored in the storage unit 120, and the calculated battery usage period Pb is converted into battery age Y. Hereinafter, the value obtained by converting the battery usage period Pb into the battery age Y is referred to as "battery age YP".

The first calculation unit 111 reads the battery usage period Pb from the storage unit 120 when the IG is turned on, and adds the read battery usage period Pb to the IG off time Tigoff received from the monitoring unit 20 (refer to the following equation (1) ).

Pb=Pb+Tigoff...(1)

After the IG is turned on, the first calculation unit 111 counts the IG on time Tigon, reads the battery usage period Pb from the storage unit 120 at a predetermined cycle, and adds the IG on time Tigon to the read battery usage period Pb. (Refer to the following formula (2)).

Pb=Pb+Tigon...(2)

Every time the first calculation unit 111 calculates the battery usage period Pb, the battery usage period Pb stored in the storage unit 120 is updated to the latest value.

FIG. 6 is a map showing the relationship between the battery usage period Pb and the storage battery age YP. The first calculation unit 111 converts the battery usage period Pb into the battery age YP using the map shown in FIG. 6 . Furthermore, the first calculation unit 111 outputs the battery age YP to the determination unit 130 .

Next, returning to FIG. 5 , the second calculation unit 112 will be described. The second calculation unit 112 calculates and stores a value (hereinafter referred to as “cell voltage excess time Tv”) obtained by accumulating the time during which the monitoring unit 20 continues to receive the overvoltage detection signal F1 over a predetermined time period (hereinafter referred to as “cell voltage excess time Tv”) and stores it in the storage unit. In 120, the calculated cell voltage exceeding time Tv is converted into battery age Y. Hereinafter, the value obtained by converting the cell voltage excess time Tv into the battery age Y is referred to as "battery age YV".

FIG. 7 is a diagram showing a method of calculating the cell voltage exceeding time Tv. A voltage violation occurs at time t1 (the overvoltage detection signal F1 is received), and when the voltage violation continues at time t2 after a predetermined time, the second calculation unit 112 determines the voltage violation and reads the voltage from the storage unit 120. The cell voltage exceeds the time Tv, and counting the cell voltage exceeded time Tv is started using the read cell voltage exceeded time Tv as an initial value. At the subsequent time t3, when the voltage violation is removed (the overvoltage detection signal F1 is no longer received), the second calculation unit 112 stops counting the cell voltage exceeding time Tv, and stores the cell voltage exceeding time Tv in the storage unit 120 . Then, when the voltage violation occurs again at time t4 and the voltage violation is determined at time t5, the second calculation unit 112 reads the cell voltage exceeding time Tv from the storage unit 120, and uses the value as the initial value to start the cell voltage violation. Count of battery voltage over time Tv. When the voltage violation is released at a subsequent time t6, the second calculating unit 112 stops counting the cell voltage exceeding time Tv, and stores the cell voltage exceeding time Tv in the storage unit 120 . It should be noted that, in the example shown in FIG. 7 , overcharging is suppressed by limiting the charging power upper limit value Win (closer to 0) during the periods t2 to t3 and t5 to t6 of voltage violation determination.

FIG. 8 is a map showing the relationship between cell voltage excess time Tv and battery age YV. The second calculation unit 112 converts the cell voltage excess time Tv into the battery age YV using the map shown in FIG. 8 . Furthermore, the second calculation unit 112 outputs the battery age YV to the determination unit 130 . It should be noted that the same processing as that of the overvoltage detection signal F1 can also be performed on the overvoltage detection signal F2.

Next, returning to FIG. 5 , the third calculation unit 113 will be described. The third calculation unit 113 calculates and stores in the storage unit 120 a value (hereinafter referred to as “overcurrent integrated value SIin”) obtained by integrating the current value charged to the storage battery 10 exceeding the input limit value Ilim for suppressing lithium deposition. , and convert the calculated overcurrent cumulative value SIin into battery age Y. Hereinafter, the value obtained by converting the integrated overcurrent value SIin into the battery age Y is referred to as "battery age YIin".

FIG. 9 is a diagram illustrating a calculation method of the integrated overcurrent value SIin. When the battery charging current Iin exceeds the input limit value Ilim from time t13 to time t14, the third calculation unit 113 calculates the current value (=Ilin -Iin) The value ΔSIin (corresponding to the area of the shaded portion in FIG. 8 ) obtained by integrating. Then, the third calculation unit 113 reads the integrated overcurrent value SIin stored in the storage unit 120, and calculates a value obtained by adding the calculated integrated value ΔSIin to the read integrated overcurrent value SIin as a new integrated overcurrent value. SIin (refer to the following formula (3)).

SIin=SIin+ΔSIin...(3)

Every time the third calculation unit 113 calculates the integrated overcurrent value SIin, the integrated overcurrent value SIin stored in the storage unit 120 is updated to the latest value. In the example shown in FIG. 9 , when the battery charging current Iin exceeds the input target value Itag at time t12, overcharging is suppressed by starting to limit the charging electric power upper limit value Win.

FIG. 10 is a map showing the relationship between overcurrent integrated value SIin and battery age Yiin. The third calculation unit 113 converts the accumulated overcurrent value SIin into the battery age YIin using the map shown in FIG. 10 .

Next, returning to FIG. 5 , the fourth calculation unit 114 will be described. The fourth calculation unit 114 calculates and stores a value obtained by integrating the discharge current Iout of the storage battery 10 (hereinafter referred to as “discharge current integration value SIout”) in the storage unit 120, and converts the calculated discharge current integration value SIout into Battery age Y. Hereinafter, the value obtained by converting the integrated discharge current value SIout into the battery age Y is referred to as "battery age YIout".

FIG. 11 is a diagram showing a calculation method of the integrated discharge current value SIout. As shown in FIG. 11, when the discharge current Iout exceeds the deviation error I0, the value ΔSIout (corresponding to the oblique line in FIG. part area). Further, the fourth calculation unit 114 reads the integrated discharge current value SIout stored in the storage unit 120, and calculates a value obtained by adding the calculated integrated value ΔSIout to the read integrated discharge current value SIout as a new integrated discharge current value. SIout (see the following formula (4)).

SIout=SIout+ΔSIout...(4)

Every time the fourth calculation unit 114 calculates the integrated discharge current value SIout, the integrated discharge current value SIout stored in the storage unit 120 is updated to the latest value.

FIG. 12 is a map showing the relationship between discharge current integrated value SIout and battery age Yiout. The fourth calculation unit 114 converts the integrated discharge current value SIout into the battery age YIout using the map shown in FIG. 12 .

In addition, each battery age YP, YT, YIin, YIout is also output to the update part 180 mentioned later.

In this way, the calculation unit 110 calculates the parameters of the battery usage period Pb, cell voltage overtime Tv, overcurrent integrated value SIin, and discharge current integrated value SIout based on the history of the usage status of the storage battery 10, and converts each parameter into Battery age YP, YT, YIin, YIout.

It should be noted that the types of parameters calculated by the calculation unit 110 are not limited to the above-mentioned Pb, Tv, SIin, and SIout. Furthermore, the number of parameters calculated by the calculation unit 110 is not limited to the above-mentioned four of Pb, Tv, SIin, and SIout. For example, from the viewpoint of reducing the processing load, the number of parameters may be set to only one battery usage period Pb. However, from the viewpoint of further improving the determination accuracy of whether or not battery diagnosis is necessary, it is preferable to use a plurality of parameters including at least any two of the above-mentioned Pb, Tv, SIin, and SIout.

Returning to FIG. 5 , in the storage unit 120 , as described above, each parameter of the battery usage period Pb, the cell voltage exceeding time Tv, the accumulated overcurrent value SIin, and the integrated discharge current value SIout is in a state of being updated to the latest value. down to store.

It should be noted that when the control circuit 100 is replaced with a new one, the information of each parameter disappears. Therefore, it is preferable to also store each parameter in the memory of a control device (for example, an ECU that controls the engine 50 ) different from the control circuit 100 to avoid simultaneous replacement of two ECUs.

The judging unit 130 judges whether the battery age Y has reached a predetermined upper limit age for each battery age YP, YT, YIin, YIout, and judges whether battery diagnosis is necessary based on the judgment result. The upper limit age is set to a value several years lower than the limit service life obtained by experiments or the like in consideration of an error amount. It should be noted that, below, the upper limit age will be described as "20 years".

The determination unit 130 determines that the battery diagnosis is necessary when at least one of the battery ages YP, YT, YIin, and YIout reaches 20 years, and determines that the battery diagnosis is not necessary when this is not the case.

FIG. 13 is a diagram illustrating a method of determining whether battery diagnosis is necessary. As shown in FIG. 13 , among the battery ages YP, YT, YIin, and YIout, when the battery age YT reaches 20 years, the determining unit 130 determines that battery diagnosis is necessary when the battery age YT reaches 20 years.

Returning to FIG. 5 , the determination unit 130 outputs the determination result to the display control unit 140 , the electric power restriction unit 150 , and the activation prohibition unit 160 .

When it is determined that the battery diagnosis is necessary, the display control unit 140 displays the above-mentioned diagnosis request message on the display device 200 . Thus, the user can grasp that the battery diagnosis time has come.

When the first period has elapsed since the display of the diagnosis request message (when it is determined that the battery diagnosis is required) and the diagnosis result has not been received from the receiving unit 170 described later, the electric power limiting unit 150 sets the charging power upper limit value. Win and discharge power upper limit value Wout are restricted (hereinafter, this restriction is referred to as "Win/Wout restriction"). As a result, the charge power and discharge power of the battery 10 are limited, so that the progress of aging of the battery 10 can be delayed. The electric power limitation unit 150 gradually increases the limitation amount by the Win/Wout limitation as time passes. It should be noted that, below, the first period will be described as "1 month".

The activation prohibition unit 160 prohibits the driving of the vehicle 5 when a second period longer than one month (first period) has elapsed since the display of the diagnosis request message has not been received from the reception unit 170 described later. System startup. As a result, the vehicle 5 cannot run, and the use of the battery 10 is substantially prohibited. It should be noted that, below, the second period will be described as "2 months".

The receiving unit 170 receives a diagnosis result (any one of the above-mentioned signals R1 to R3 ) from the diagnosis device 300 when the user takes the vehicle 5 into a repair shop and receives a battery diagnosis. Receiving unit 170 outputs the received diagnosis result to update unit 180 , display control unit 140 , power limiting unit 150 , and activation prohibition unit 160 .

The update unit 180 updates each parameter (battery usage period Pb, cell voltage excess time Tv, overcurrent integrated value SIin, discharge current integrated value SIout) recorded in the storage unit 120 based on the result of the battery diagnosis received via the receiving unit 170 . to update.

First, the update method when the diagnosis result is "continuous use possible" will be described. In this case, when there is a battery age Y of 20 years that has reached the upper limit age among the four battery ages Y calculated by the calculation unit 110 (after the diagnosis request message is displayed), the update unit 180 sets the battery age Y to The specified age lower than 20 years is returned, and the storage battery age Y which has not reached 20 years is also set as the specified age. It should be noted that, in the following description, the predetermined age is "15 years".

FIG. 14 is a diagram showing a method of updating the battery age Y when the battery diagnosis is received after the display of the diagnosis request message and the diagnosis is “continuously usable”. In the example shown in FIG. 14 , the update unit 180 reverts the battery age YT that has reached 20 years to 15 years by five years, and also updates the other battery ages YP, YIin, and YIout that have not reached 20 years to 15 years. That is, the update unit 180 calculates the value of each parameter corresponding to 15 years by using the above-mentioned maps in FIGS. Each parameter of the unit 120 is updated. With such an update, the initial value of the age Y of each storage battery becomes 15 years after the diagnosis. That is, the first diagnosis request message is displayed when 20 years have elapsed, but when the battery 10 continues to be used, the second and subsequent diagnosis request messages are displayed every five years to urge the user to perform early diagnosis.

On the other hand, when the battery age Y has not reached 20 years (before the display of the diagnosis request message), the update unit 180 uses The age Y of each storage battery is returned to 15 years, and if this is not the case, the age Y of each storage battery is maintained as it is without being updated. In addition, in the following description, the storage battery age Y immediately before 20 years is 15 years or more and less than 20 years.

FIGS. 15 and 16 are diagrams showing a method of updating the battery age Y when a diagnosis is made before the display of the diagnosis request message and the battery age Y is diagnosed as "continuously usable". In this case, the update unit 180 first determines whether or not there is a battery age Y of 15 years or more and less than 20 years.

If there is a battery age Y between 15 and 20 years, the updating unit 180 returns the battery age Y between 15 and 20 to 15 as shown in FIG. 15 , and updates the other battery ages to 15 as well. Accordingly, the next diagnosis request message is displayed when five years have passed since the diagnosis. Therefore, it is possible to avoid a situation where a diagnosis request message is displayed immediately after the diagnosis.

On the other hand, when the age Y of each storage battery is less than 15 years, the updating unit 180 does not update the age Y of each storage battery as shown in FIG. 16 . Therefore, it is avoided that the diagnosis request message is displayed before 20 years have elapsed during the service period of the storage battery 10 .

Next, an update method when the diagnosis result is "unusable" will be described. In this case, the update unit 180 updates all battery ages Y to 20 years, which is the upper limit age. That is, the update unit 180 calculates the value of each parameter corresponding to 20 years by using the above-mentioned maps in FIGS. Each parameter of the unit 120 is updated. With this update, the age Y of each storage battery becomes 20 years of the upper limit age after the diagnosis of "no longer usable". And, as described later, an unusable message is displayed.

Next, an update method when the diagnosis result is "new product status" will be described. In this case, the update unit 180 initializes all battery ages Y to 0 years. That is, the update unit 180 initializes each parameter stored in the storage unit 120 to zero.

In this way, update unit 180 updates each parameter described in storage unit 120 based on the result of the battery diagnosis.

Returning to FIG. 5 , when the diagnosis result is “unusable”, if the diagnosis request message is being displayed, the display control unit 140 does not display the diagnosis request message and displays the unusable message on the display device 200 . On the other hand, when the diagnosis result is "continued use possible" or "new product status", the display control unit 140 does not display these messages during the period when the diagnosis request message or the unusable message is displayed.

When the diagnosis result is "continuous use possible" or "new product status", the electric power limiting unit 150 cancels the Win/Wout limitation if it is the Win/Wout limitation period.

The activation prohibiting unit 160 prohibits the activation of the drive system of the vehicle 5 when the diagnosis result is "unable to continue use". On the other hand, when the diagnosis result is "continuously usable" or "new product status", display control unit 140 releases the prohibition of activation of the drive system during the period of prohibition of activation of the drive system.

FIG. 17 is a flowchart showing a processing procedure mainly for realizing functions related to pre-battery diagnosis processing among the functions of the control circuit 100 described above. It should be noted that each step in the flow chart shown below (hereinafter, the step is simply referred to as "S") is basically realized by software processing performed by the control circuit 100, but it may also be realized by an electronic circuit provided in the control circuit 100. Wait for the hardware processing to realize.

In S10 , the control circuit 100 determines whether or not a battery diagnosis result (any one of the signals R1 to R3 ) has been received from the diagnosis device 300 . When the battery diagnosis result has not been received (NO in S10), the process proceeds to S11. When the battery diagnosis result is received (YES in S10 ), the process ends.

In S11, the control circuit 100 calculates the parameters of the battery usage period Pb, cell voltage excess time Tv, overcurrent integrated value SIin, and discharge current integrated value SIout based on the history of the usage status of the storage battery 10 as described above, and Convert each parameter into battery age YP, YT, YIin, YIout respectively. In addition, each parameter (Pb, Tv, SIin, SIout) memorize|stored in memory (storage part 120) is updated to the latest value.

In S12, the control circuit 100 judges whether at least one of the storage battery ages YP, YT, YIin, and YIout has reached 20 years (the upper limit age).

When none of the battery ages Y has reached 20 years (NO in S12), the control circuit 100 does not display a diagnosis request message on the display device 200 in S13.

On the other hand, when at least one battery age Y reaches 20 years (YES in S12), the control circuit 100 causes a diagnosis request message to be displayed on the display device 200 in S14.

In S15, the control circuit 100 determines whether or not two months (second period) have elapsed since the display of the diagnosis request message was started.

When two months have elapsed since the display of the diagnosis request message started (YES in S15 ), the control circuit 100 prohibits activation of the drive system of the vehicle 5 in S18 .

On the other hand, when two months have not passed since the display of the diagnosis request message started (NO in S15), the control circuit 100 judges in S16 whether one month has passed since the start of the display of the diagnosis request message (the first period ).

When one month has passed since the display of the diagnosis request message was started (YES in S16), the control circuit 100 performs Win/Wout limitation in S17. When one month has not elapsed since the diagnosis request message was displayed (NO in S16 ), this process ends.

FIG. 18 is a flowchart showing a processing procedure mainly for realizing the functions related to the processing after the battery diagnosis among the functions of the control circuit 100 described above.

In S20 , the control circuit 100 determines whether or not a battery diagnosis result (any one of the signals R1 to R3 ) has been received from the diagnosis device 300 . When the battery diagnosis result is not received (NO in S20), this process ends. When the battery diagnosis result is received (YES in S20), the process proceeds to S21.

In S21, the control circuit 100 judges whether the diagnosis result is "continued use" (that is, the signal R1 is received from the diagnosis device 300). When the diagnosis result is "continuous use possible" (YES in S21), the process proceeds to S22. If this is not the case (NO in S21), the process proceeds to S28.

In S22, the control circuit 100 judges whether it is before displaying a diagnosis request message. Before displaying a message is requested for diagnosis (YES in S22), the process proceeds to S23. When the display of the message is requested for diagnosis (NO in S22), the process proceeds to S25.

In S23, the control circuit 100 judges whether the age Y of each storage battery is less than 15 years. When the age Y of each storage battery is less than 15 years (YES in S23), the process proceeds to S24. When at least one of the storage battery ages Y is 15 years or more (NO in S23), the process proceeds to S25.

In S24, the control circuit 100 maintains the parameters stored in the memory without updating them.

In S25, the control circuit 100 updates each parameter stored in the memory so that the age Y of each storage battery becomes 15 years (predetermined age).

In S26, the control circuit 100 makes the message displayed on the display device 200 (diagnosis request message or unusable message) not displayed.

In S27, the control circuit 100 releases the output restriction (Win/Wout restriction or activation prohibition of the drive system) of the battery 10 .

In S28, the control circuit 100 judges whether the diagnosis result is "unable to continue to use" (that is, the signal R2 is received from the diagnosis device 300). When the diagnosis result is not "continued use" but "new product status" (No in S28), the process proceeds to S29. When the diagnosis result is "unable to continue use" (YES in S28), the process proceeds to S30.

In S29, the control circuit 100 initializes each parameter stored in the memory so that the age Y of each storage battery becomes 0 years. Then, the process proceeds to S26 and S27, the message displayed on the display device 200 is hidden, and the output restriction of the storage battery 10 is released.

In S30, the control circuit 100 updates each parameter stored in the memory so that the age Y of each storage battery becomes 20 years (upper limit age). Then, in S31 and S32, the control circuit 100 hides the diagnosis request message displayed on the display device 200 and displays an unusable message. In addition, the control circuit 100 prohibits activation of the drive system of the vehicle 5 in S33.

FIG. 19 is a diagram illustrating a flow of actions of the vehicle 5 controlled by the control circuit 100 .

First, the behavior of the vehicle 5 before the battery diagnosis will be described. Before the battery diagnosis, when any of the storage battery ages Y reaches 20 years, the display of the diagnosis request message starts (time t21). Thus, the user can grasp that the battery diagnosis time has come.

When one month has elapsed since the display of the diagnosis request message and no diagnosis has been performed, the Win/Wout restriction is started (time t22 ). As a result, the charge power and discharge power of the battery 10 are limited, so that the progress of aging of the battery 10 can be delayed.

When two months have elapsed since the diagnosis request message was displayed and no diagnosis has been made, activation of the drive system of the vehicle 5 is prohibited (time t23 ). Thereby, the use of the storage battery 10 is substantially prohibited, and it is suppressed that the storage battery 10 continues to be used in a degraded state.

Next, the behavior of the vehicle 5 when the user who has observed the diagnosis request message brings the vehicle 5 into a repair shop to receive a battery diagnosis will be described.

When the diagnosis result is "no further use", the start of the drive system is prohibited. When the diagnosis result is received and the battery 10 is replaced with a new one, the message displayed on the display device 200 is hidden, and the activation prohibition of the drive system is also released.

When the diagnosis result is "continuous use possible", each parameter is updated so that the age Y of each storage battery becomes 15 years. In this way, even if the storage battery 10 is not replaced with a new one, the message displayed on the display device 200 is hidden, and the Win/Wout restriction or activation prohibition of the drive system is released. In addition, since the next diagnosis request message is displayed five years later, the user can be urged to perform battery diagnosis earlier than the first 20 years.

As described above, according to the control circuit 100 of this embodiment, when the storage battery age Y (a value corresponding to the estimated value of the lithium deposition amount) calculated based on the history of the usage status of the storage battery 10 reaches the upper limit age, a diagnosis request message is displayed and Urges the user to perform a battery diagnosis. Then, when the diagnosis has not been performed for a predetermined period of time, the use of the storage battery 10 is restricted (restricted or prohibited). Therefore, it is possible to avoid failure of the storage battery 10 due to continued use in a degraded state.

It should be considered that all points of the embodiments disclosed this time are illustrative and not restrictive. The scope of the present invention is indicated not by the above description but by the scope of the claims, and it is intended that all changes within the meaning and range equivalent to the scope of the claims are included.

Label description

5 vehicle, 10 battery, 10# battery unit, 11 battery block, 12 temperature sensor, 14 voltage sensor, 16 current sensor, 20 monitoring unit, 20a voltage comparison circuit, 20b overvoltage detection circuit, 20c cut-off counter, 22, 24 system Main relay, 41, 42 motor generator, 50 engine, 60 power split mechanism, 70 drive shaft, 80 wheel, 100 control circuit, 110 calculation unit, 111 first calculation unit, 112 second calculation unit, 113 third calculation unit , 114 fourth calculation unit, 120 storage unit, 130 determination unit, 140 display control unit, 150 power limit unit, 160 start prohibition unit, 170 reception unit, 180 update unit, 200 display device, 300 diagnosis device.

Claims (4)

1. A control device for a secondary battery, which is a control device for a secondary battery (10) capable of diagnosing an aging state by a diagnostic device (300), wherein the control device for a secondary battery is characterized by comprising: A determination unit (130) that determines whether the diagnosis is necessary based on a history of the usage status of the secondary battery; a warning unit (140) warning a user to accept the diagnosis when the determination unit determines that the diagnosis is necessary; and A limiting unit (150, 160) that limits the output of the secondary battery when the warning unit warns the user that the diagnosis is not performed within a predetermined period of time after receiving the diagnosis, The determination unit determines whether the diagnosis is necessary for each of a plurality of parameters including a usage time of the secondary battery and an accumulation of time during which the voltage of the secondary battery exceeds a reference value. value, an accumulated value of a part exceeding a predetermined value in the charge current of the secondary battery, and at least two values of an accumulated value of the discharge current of the secondary battery, The determination unit calculates a battery age indicating a degree of deterioration of the secondary battery for each of the plurality of parameters, and determines that it is necessary when at least one of the calculated plurality of battery ages reaches an upper limit age. said diagnosis, The control device further includes a changing unit (180) that changes the age of the battery according to a result of the diagnosis when the diagnosis is performed, The changing unit sets a plurality of battery ages as the upper limit age when the result of the diagnosis indicates that the secondary battery cannot be used any longer, The warning unit warns the user that the secondary battery cannot be used when the result of the diagnosis indicates that the secondary battery cannot be used any longer, The restriction unit (160) prohibits charge and discharge of the secondary battery when the result of the diagnosis indicates that the secondary battery cannot be used any longer. 2. The control device for a secondary battery according to claim 1, wherein: The control device also has: a display device (200) for displaying information to a user; and a power control device (30) that controls power for charging and discharging the secondary battery, the warning section warns a user to accept the diagnosis by displaying a message prompting the diagnosis to be performed on the display device, The limiting unit limits the output of the secondary battery by controlling the power control device. 3. The control device for a secondary battery according to claim 1, wherein: The determination unit determines whether the diagnosis is necessary based on at least any one of the following parameters: a usage time of the secondary battery, an accumulated value of time when the voltage of the secondary battery exceeds a reference value, the two A cumulative value of a part of the charging current of the secondary battery exceeding a predetermined value, and a cumulative value of a discharging current of the secondary battery. 4. A control method of a secondary battery, which is a control method performed by a control device (100) of a secondary battery (10) capable of diagnosing an aging state using a diagnostic device (300), wherein the control method of the secondary battery The method is characterized in that it comprises the steps of: a step of determining whether the diagnosis is necessary based on a history of the usage status of the secondary battery; the step of alerting the user to accept said diagnosis if it is determined that said diagnosis is required; and a step of limiting the output of the secondary battery when the diagnosis has not been performed for a predetermined period of time after warning the user to accept the diagnosis, The step of determining whether the diagnosis is necessary determines whether the diagnosis is necessary for each of a plurality of parameters, the plurality of parameters including the use time of the secondary battery, the voltage of the secondary battery exceeding At least two values of a time-accumulated value of a reference value, an accumulated value of a part of the charge current of the secondary battery exceeding a predetermined value, and an accumulated value of a discharge current of the secondary battery, The step of determining whether the diagnosis is necessary calculates a battery age indicating a degree of deterioration of the secondary battery for each of the plurality of parameters, and when at least one of the calculated plurality of battery ages reaches When the upper limit age is judged as requiring the diagnosis, The control method further includes the step of changing the age of the battery according to a result of the diagnosis when the diagnosis is performed, In the step of changing the battery age, when the result of the diagnosis indicates that the secondary battery cannot be used any longer, setting a plurality of the battery ages as the upper limit age, In the step of warning the user to accept the diagnosis, when the result of the diagnosis indicates that the secondary battery cannot be used any longer, the user is warned that the secondary battery cannot be used, In the step of limiting the output of the secondary battery, charging and discharging of the secondary battery is prohibited when the result of the diagnosis indicates that the secondary battery cannot be used any longer.