JP5777303B2 - Battery deterioration detection device, battery deterioration detection method and program thereof - Google Patents

Description

  The present invention relates to a battery deterioration detection device, a battery deterioration detection method, and a program for detecting deterioration of a storage battery.

  In an electric system that performs electric control using electric power stored in a storage battery, it is desirable to have a mechanism for detecting a battery deterioration state early and notifying a user. Thereby, it becomes possible to prevent the occurrence of excessive costs due to the early replacement of the storage battery and the failure of the electric system due to the replacement delay of the storage battery. Patent Document 1 is disclosed as a technique for detecting battery deterioration.

JP 2003-153454 A

  By the way, the technique of the above-mentioned patent document 1 shifts to the constant voltage charge which maintains a voltage continuously, after carrying out constant current charge of the lithium ion secondary battery and a voltage reaches | attains a regulation voltage value. Then, the current behavior is measured from the current flowing through the battery when the charging method is switched to constant voltage charging and the current flowing through the battery after a predetermined time has elapsed, and the degree of deterioration of the battery is estimated.

However, in the technique of Patent Document 1, when the load pattern of the storage battery cannot be assumed, it is understood when a situation occurs in which constant current charging is performed and switching to constant voltage charging can be performed after the voltage reaches a specified voltage value. Therefore, there is a problem that deterioration of the storage battery cannot be detected at a desired time.
Moreover, when estimating a deterioration degree from an electric current or a voltage in the environment where the temperature of a storage battery changes, it is necessary to exclude the influence which temperature has on a battery characteristic.

  Accordingly, an object of the present invention is to provide a battery deterioration detection device, a battery deterioration detection method, and a program thereof that can solve the above-described problems.

In order to achieve the above object, the present invention obtains a current value to be input to and output from a storage battery and a voltage value applied to the storage battery, and the fluctuation range of the current value when the current value fluctuates more than a certain value. And an internal resistance value calculation unit that calculates the current internal resistance value of the storage battery using the fluctuation range of the voltage value at that time, and the current internal resistance value corresponds to the current temperature of the storage battery by dividing by the internal resistance initial value, calculates the deterioration rate of the battery at the current temperature of the storage battery, the storage battery or an internal resistance Rlimit when a condition should be determined to be a life, operational When the open circuit voltage value when the maximum charging rate of the storage battery is sometimes assumed is V_VOCmax, and when the open circuit voltage value is V_VOCmax, the charging current value for the storage battery is the maximum current design value Icmax in the storage battery Previous The value of the voltage applied to the storage battery (V_VOCmax + (Icmax × Rlimit) ), the open circuit voltage value when the minimum charging rate of the storage battery that is assumed during operation and V_VOCmin of discharging of the storage battery when it is in the open circuit voltage V_VOCmin the value of the voltage applied to the storage battery when a maximum design current Idmax current value in said storage battery (V_VOCmin- (Idmax × Rlimit)) , one of said internal resistance when outside the allowable voltage value of said battery Warning information when the degradation rate is equal to or greater than the critical degradation rate by comparing the critical degradation rate indicating the ratio of the value Rlimit to the initial internal resistance value of the storage battery and the degradation rate of the storage battery at the current temperature. A battery deterioration information processing unit for outputting the battery deterioration information to a monitor device.

  In the battery deterioration detection device according to the present invention, the internal resistance value calculation unit may determine that the fluctuation of the current flowing into and out of the storage battery is not more than a specified value for a predetermined period before the current value fluctuates more than a certain value. When the state continues, the current internal resistance value is calculated.

  The battery deterioration detection device according to the present invention further includes an internal resistance initial value storage unit that stores an internal resistance initial value at each of different temperatures of the storage battery, and the internal resistance value calculation unit acquires the acquired The internal resistance initial value corresponding to the temperature of the storage battery is calculated based on the internal resistance initial value at each of different temperatures recorded in the internal resistance initial value storage unit.

  According to the present invention, in the battery deterioration detection device described above, the battery deterioration information processing unit calculates an average of a plurality of calculated deterioration rates, and outputs the average value of the deterioration rates to the monitor device. And

  Further, according to the present invention, the above-described battery deterioration detection device has the square root rule indicating the relationship between the operation days of the storage battery and the deterioration rate, and the internal resistance value of the storage battery in a state where the storage battery should be determined to have a life. Using the deterioration rate, calculating the life determination days that the storage battery is determined to have a life, subtracting the current operation days from the life determination days, and calculating the remaining life days calculation unit for calculating the remaining life days of the storage battery; It is characterized by providing.

Further, the present invention provides a battery deterioration detection method for a battery deterioration detection device, wherein a current value input / output to / from a storage battery and a voltage value applied to the storage battery are acquired, and the current value when the current value fluctuates by a certain value or more. The current internal resistance value of the storage battery is calculated using the fluctuation range of the current value and the fluctuation range of the voltage value at that time, and the current internal resistance value corresponds to the current temperature of the storage battery. by dividing by the internal resistance initial value, calculates the deterioration rate of the battery at the current temperature of the storage battery, the storage battery or an internal resistance Rlimit when a condition should be determined to be a life, operational when the current value of charging of the battery when it is in the open-circuit voltage value V_VOCmax and V_VOCmax the open circuit voltage value when the maximum charging rate of the battery is the maximum design current Icmax in the storage battery during envisioned The value of the voltage applied to the serial storage battery (V_VOCmax + (Icmax × Rlimit) ), and discharging of the battery when it is in the open circuit voltage V_VOCmin open circuit voltage value as V_VOCmin when the minimum charging rate of the storage battery that is assumed during operation the internal when the voltage value the current value according to the battery when the maximum design current Idmax in the storage battery with the (V_VOCmin- (Idmax × Rlimit)) , one of, departing from the allowable voltage value of said battery A warning is given when the deterioration rate is equal to or greater than the limit deterioration rate by comparing the limit deterioration rate indicating the ratio of the resistance value Rlimit to the initial internal resistance value of the storage battery and the deterioration rate of the storage battery at the current temperature. The information is output to a monitor device.

The present invention also provides a computer of a battery deterioration detection device for acquiring a current value input to and output from a storage battery and a voltage value applied to the storage battery, and changing the current value when the current value fluctuates more than a certain value. The internal resistance value calculation process for calculating the current internal resistance value of the storage battery using the width and the fluctuation range of the voltage value at that time, the current internal resistance value corresponds to the current temperature of the storage battery by dividing by the internal resistance initial value, calculates the deterioration rate of the battery at the current temperature of the storage battery, the storage battery or an internal resistance Rlimit when a condition should be determined to be a life, operational If the current value of charging of the battery when it is in the open-circuit voltage value V_VOCmax and V_VOCmax the open circuit voltage value when the maximum charging rate of the battery is the maximum design current Icmax in the storage battery during envisioned A voltage value applied to the battery in (V_VOCmax + (Icmax × Rlimit) ), to said battery when it is in the open circuit voltage V_VOCmin open circuit voltage value as V_VOCmin when the minimum charging rate of the storage battery that is assumed during operation the value of the voltage applied to the battery when the current value of the discharge is the maximum design current Idmax in the storage battery (V_VOCmin- (Idmax × Rlimit)) , one of said when outside the allowable voltage value of said battery When the limit deterioration rate indicating the ratio of the internal resistance value Rlimit to the initial internal resistance value of the storage battery is compared with the deterioration rate of the storage battery at the current temperature, the deterioration rate is equal to or greater than the limit deterioration rate. It is a program characterized by functioning as battery deterioration information processing for outputting warning information to a monitor device.

  According to the present invention, the current parameter value, voltage parameter value, and temperature parameter value of the storage battery are intermittently obtained, and the internal resistance value at that time is calculated using the parameter values, and the deterioration rate of the storage battery is calculated. At the same time, it is determined whether the deterioration rate is equal to or higher than the limit deterioration rate using the accurate deterioration rate. Therefore, the deterioration state of the battery can be detected regardless of the load pattern of the storage battery.

It is a block diagram which shows the structure of a battery deterioration detection apparatus. It is a schematic block diagram of BMS and a storage battery. It is a functional block diagram of a controller. It is a figure which shows the relationship between the internal resistance value of a storage battery, and temperature. It is a figure which shows the equivalent circuit of a secondary battery. It is a graph which shows the relationship between the operation days of a storage battery, and a deterioration rate.

Hereinafter, a battery deterioration detection apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing the configuration of the battery deterioration detection device according to the embodiment.
In the present embodiment, the battery deterioration detection device 1 is a new transportation system such as RTG (Rubber Tiered Gantry crane), APM (Automated People Mover), or LRT (Light Rail Transit) that operates based on electric power stored in a storage battery. The vehicle is equipped.
The battery deterioration detection device 1 includes a storage battery 10, a BMS (Battery Management System) 20, a controller (Programmable Logic Controller) 30, a display device 40, and a power load 50.

  Here, the battery deterioration detection apparatus 1 of the present invention is an airplane in which a propeller or a screw is connected to an electric motor that is an electric vehicle or an industrial vehicle such as an electric vehicle or a forklift, or an electric vehicle, in addition to RTG, APM, and LRT. Alternatively, it may be provided in a moving body such as a ship. Furthermore, the battery deterioration detection device 1 is provided in a stationary system such as a household power storage system or a grid-connected smoothing power storage system combined with a natural energy power generation such as a windmill or sunlight. It may be.

  The storage battery 10 supplies power to the power load 50 of the electric system provided with the battery deterioration detection device 1, and is constituted by the secondary battery 11 in this embodiment. The storage battery 10 may be configured by connecting a plurality of secondary batteries 11 in series. The storage battery 10 may be a plurality of secondary batteries 11 connected in parallel. Various sensors for measuring temperature, voltage, current, etc. are attached to the secondary battery 11 constituting the storage battery 10, and the measurement information measured and output by these sensors is input to the BMS 20 described in detail later. Is done. In addition, when the storage battery 10 is comprised by the several secondary battery 11, the said various sensors are attached to each.

  The controller 30 receives the measurement information of the storage battery 10 transmitted from the BMS 20 and displays the related information (such as the deterioration rate of the storage battery and the remaining life days) calculated based on the measurement information on the display device 40. It controls and makes it display on the said display apparatus 40 suitably. Further, when the controller 30 determines that the related information is an abnormal value, the controller 30 turns on an abnormal lamp 401 built in the display device 40 or the like. In addition, an alarm may be displayed by operating a sound device such as a buzzer built in the display device 40, and a visual and auditory sense is stimulated by light and sound. May be prompted.

The display device 40 is a monitor such as a liquid crystal panel including the acoustic device, for example, and displays the related information of the secondary battery 11 constituting the storage battery 10 based on the control from the controller 30.
The power load 50 is a power converter such as an electric motor or an inverter connected to a vehicle wheel, for example. The power load 50 may be an electric motor that drives a wiper or the like.

Next, after briefly reviewing the BMS 20, its operation and the like will be described in detail.
As shown in FIG. 1, the BMS 20 of the battery deterioration detection device 1 includes a CMU (Cell Monitor Unit) 21 and a BMU (Battery Management Unit) 23.
Here, the CMU 21 includes an ADC (Analog Digital Converter) (not shown), receives a plurality of the measurement information detected and output by the various sensors as analog signals, and the analog signals correspond to the ADCs, respectively. After being converted into a digital signal, it is output to the BMU 23 as a plurality of parameters for calculating the related information. And in this embodiment, as shown in FIG. 1, CMU21 is connected with the secondary battery 11 by the signal wire | line.

Further, the BMU 23 outputs the parameters of the storage battery 10 input from the CMU 21 to the controller 30.
Although only one CMU 21 is shown here, the present invention is not limited to this mode. For example, when the storage battery 10 includes a plurality of secondary batteries 11, a plurality of CMUs 21 may be provided, and a plurality of secondary batteries 11 may be connected to each CMU 21. On the other hand, the CMU 21 may be provided in a one-to-one relationship. That is, as long as the BMU 23 can acquire a plurality of parameters necessary for performing the deterioration rate calculation process and the remaining life days calculation process from the CMU 21, the number of the CMUs 21 may be any number. If the BMU 23 is configured including the CMU 21, the BMS 20 may be configured only by the BMU 23.

FIG. 2 is a schematic configuration diagram of a BMS and a storage battery.
Next, the internal configuration and operation of the BMS 20 will be described in detail with reference to FIG.
As shown in FIG. 2, a voltmeter 3 is provided for the secondary battery 11 constituting the storage battery 10. Specifically, the voltmeter 3 is connected between the positive electrode terminal and the negative electrode terminal of the secondary battery 11. The CMU 21 includes a parameter value detection unit 211. The parameter value detection unit 211 acquires a voltage value as measurement information measured and output by the voltmeter 3 as an analog signal (the analog signal is a parameter value detection unit). 211).

Further, the ammeter 2 is connected between the storage battery 10 and the power load 50 in order to measure the current flowing through the power load 50. The parameter value detection unit 211 acquires a current value as measurement information measured and output by the ammeter 2 as an analog signal (the analog signal is input to the parameter value detection unit 211).
A thermometer 4 is attached to the housing of the secondary battery 11 that constitutes the storage battery 10. Then, the parameter value detection unit 211 acquires a temperature value as measurement information measured and output by the thermometer 4 as an analog signal (the analog signal is input to the parameter value detection unit 211).

  The parameter value detection unit 211 incorporates the ADC, and converts an analog signal obtained from the ammeter 2, the voltmeter 3, and the thermometer 4 into a digital signal. Then, the parameter value corresponding to each is output to the BMU 23. Further, the BMU 23 outputs the acquired current value, voltage value, and temperature value to the controller 30. Then, the controller 30 performs the deterioration rate calculation process and the remaining life days calculation process using the acquired current value, voltage value, and temperature value.

FIG. 3 is a functional block diagram of the controller.
As shown in FIG. 3, the controller 30 includes a parameter acquisition unit 31, a storage unit 32 (an internal resistance initial value storage unit), a battery deterioration information processing unit 33 that performs a deterioration rate calculation process, and a remaining life that performs a remaining life days calculation process. The number of days calculation part 34 and the internal resistance value calculation part 35 which calculates the internal resistance value of the storage battery 10 are provided.
First, the parameter acquisition unit 31 has a parameter value (secondary value) corresponding to a voltage value between terminals of a secondary battery 11 provided in the storage battery 10 (voltage value between a positive terminal and a negative terminal in the secondary battery 11). The parameter of the voltage of the battery 11 is referred to as an inter-terminal voltage parameter V, and its value is referred to as an inter-terminal voltage parameter value).
Further, the parameter acquisition unit 31 obtains a parameter value corresponding to the current value flowing into and out of the storage battery 10 measured by the ammeter 2 (this parameter is referred to as a current parameter I, and this value is referred to as a current parameter value) from the BMS 20. Enter to get.
Further, the parameter acquisition unit 31 is a parameter value of the temperature of the casing of the secondary battery 11 constituting the storage battery 10 measured by the thermometer 4 (this parameter is called a temperature parameter T, and this value is called a temperature parameter value). ) Is input from the BMS 20 and acquired.
Then, the parameter acquisition unit 31 outputs the acquired current parameter value, voltage parameter value, and temperature parameter value to the internal resistance value calculation unit 35 and records them in the storage unit 32.

  Here, the internal resistance value calculation unit 35 stores the current parameter value, the voltage parameter value, and the temperature parameter value acquired from the parameter acquisition unit 31 before the previous time in a memory or the like. Then, the internal resistance value calculation unit 35 compares the current parameter value acquired last time with the current parameter value acquired from the current parameter acquisition unit 31, and determines whether or not the value has fluctuated by a certain value or more. Then, the internal resistance value calculation unit 35 calculates the internal resistance value of the storage battery 10 when it is determined that the current parameter values of the previous time and the current time fluctuate by a certain value or more. In addition, when the current parameter value of the last time and this time does not fluctuate more than a fixed value, noise may be mixed when calculating the internal resistance of the storage battery 10. Therefore, when the current and current current parameter values have not changed by a certain value or more, the internal resistance value calculation unit 35 stops calculating the internal resistance value of the storage battery 10. In this internal resistance value calculation process, the internal resistance value calculation unit 35 calculates the difference between the current parameter value of the previous time and the current value to obtain the fluctuation value ΔI of the current parameter value, and also the voltage parameter of the previous time and the current time. The difference between the values is calculated to obtain a fluctuation value ΔV of the voltage parameter value. Then, the internal resistance value calculating unit 35 determines whether the calculated ΔI is equal to or greater than a certain value. If the calculated ΔI is equal to or greater than the certain value, the internal resistance value R of the storage battery 10 is set to the current parameter value variation value ΔI Using the fluctuation value ΔV of the voltage parameter value when the current parameter value fluctuates, R = ΔV ÷ ΔI is calculated.

FIG. 4 is a diagram showing the relationship between the internal resistance value of the storage battery and the temperature.
The controller 30 stores in advance an initial value Rini of an internal resistance value corresponding to a plurality of temperatures of the storage battery 10 (hereinafter referred to as an internal resistance initial value Rini) in the storage unit 32. Here, as shown in FIG. 4, it is known that the internal resistance value of the storage battery 10 decreases in inverse proportion as the temperature rises. Further, as shown in FIG. 4, it is known that the internal resistance value of the storage battery 10 changes its resistance characteristic (relationship between the internal resistance value and temperature) in the direction of the arrow as the storage battery 10 deteriorates. . That is, it is known that when the storage battery 10 deteriorates, the internal resistance value increases even before the deterioration, even at the same temperature.

  The deterioration rate γ of the storage battery 10 (secondary battery 11) is a ratio of the current internal resistance value R to the internal resistance initial value Rini, and can be calculated by the deterioration rate calculation formula γ = R ÷ Rini. However, as shown in FIG. 4, the internal resistance initial value Rini also changes according to the temperature of the storage battery 10. Therefore, by using the internal resistance initial value Rini of the storage battery 10 at the same temperature as the temperature of the storage battery 10 when the current internal resistance value is calculated, it is possible to calculate the deterioration rate γ with high accuracy. Then, the internal resistance value calculating unit 35 immediately starts the internal resistance initial value of the storage battery 10 at the same temperature as the temperature indicated by the newly acquired temperature parameter value immediately before determining that the current parameter value of the previous time and the current value fluctuated by a certain value or more. The value Rini is calculated.

At this time, the internal resistance value calculation unit 35 reads the internal resistance initial value Rini corresponding to a plurality of temperatures in the vicinity of the temperature indicated by the newly acquired temperature parameter value from the storage unit 32, and newly acquires it by interpolation calculation or the like. The internal resistance initial value Rini corresponding to the temperature parameter is calculated. Then, the internal resistance value calculation unit 35 outputs the calculated internal resistance value R and the internal resistance initial value Rini to the battery deterioration information processing unit 33. Then, the battery deterioration information processing unit 33 calculates the current deterioration rate γ of the storage battery 10 using the above-described deterioration rate value calculation formula.
The battery deterioration information processing unit 33 inputs and acquires the internal resistance value R and the internal resistance initial value Rini calculated by the internal resistance value calculation unit 35 from the internal resistance value calculation unit 35 for each predetermined period. The deterioration rate γ is calculated and output to the display device 40. At this time, when a plurality of deterioration rates γ are calculated within the predetermined period, the battery deterioration information processing unit 33 outputs the average value to the display device 40. The display device 40 displays the deterioration rate γ acquired by inputting from the controller 30 on a monitor or the like.

  Further, when the calculated deterioration rate γ or the average value thereof is equal to or greater than the limit deterioration rate γlimit (lifetime determination value of deterioration rate) for determining the life of the storage battery, the battery deterioration information processing unit 33 Is determined to be a lifetime, and warning information is output to the display device 40. Then, the display device 40 informs the user of the storage battery by turning on the abnormal lamp 401 or the like. The battery deterioration information processing unit 33 reads the limit deterioration rate γlimit from the storage unit 32 and determines whether the calculated deterioration rate γ and the average value are equal to or higher than the limit deterioration rate γlimit. Compare with the deterioration rate γ and its average value.

According to the above-described processing, the current parameter value, voltage parameter value, and temperature parameter value of the storage battery 10 are intermittently obtained, and the internal resistance value R at that time is calculated using these parameter values. The deterioration rate of 10 is calculated, and it is determined whether the deterioration rate γ is equal to or greater than the limit deterioration rate γlimit. Therefore, the deterioration state of the battery can be detected regardless of the load pattern of the storage battery 10.
Further, by using the internal resistance initial value Rini of the storage battery 10 at the same temperature as the temperature of the storage battery 10 when the current internal resistance value is calculated, an accurate deterioration rate γ is calculated, and the deterioration rate It is determined whether or not the critical deterioration rate γlimit is equal to or greater than γ. Therefore, since the deterioration state is detected by eliminating the influence of the temperature on the internal resistance of the storage battery, the deterioration state can be accurately determined.
In addition, since the display device 40 can display a highly accurate deterioration state of the storage battery 10, it is possible to prevent occurrence of excessive cost due to early replacement of the storage battery 10 or malfunction due to replacement delay at a more appropriate timing. Is possible.

Here, the details of the limit deterioration rate γlimit will be described.
The limit deterioration rate γlimit is a ratio of the internal resistance value Rlimit when the storage battery 10 is to be determined to have a life to the initial internal resistance value Rini of the storage battery 10, and is calculated by γlimit = Rlimit ÷ Rini. I can do it. Here, the internal resistance value Rlimit when the storage battery 10 is to be determined to have a lifetime is the open circuit voltage when the storage battery 10 is assumed to have a maximum SOC (state of charge) during operation. Is V_VOCmax, and the maximum current design value flowing into the storage battery 10 during charging is Icmax, the voltage value applied to the storage battery 10 during operation = V_VOCmax + (Icmax × Rlimit), or the minimum SOC of the storage battery 10 assumed during operation When V_VOCmin is the open circuit voltage when Id and the maximum current design value flowing into the storage battery 10 during discharge is Idmax, the voltage value applied to the storage battery 10 during operation = V_VOCmin− (Idmax × Rlimit) It is an internal resistance value when the allowable voltage value of the storage battery 10 deviates.

  In addition, the maximum current design value Icmax flowing into the storage battery 10 at the time of charging described above is expressed as Icmax = | Pcmax ÷ Vmin |, where Pcmax is the maximum charge power design value and Vmin is the minimum battery voltage design value. Is a value calculated by. Further, the maximum design current value Idmax flowing into the storage battery 10 at the time of discharging is calculated as Icmax = | Pcmax ÷ Vmin |, where Pcmin is the minimum charge power design value of the storage battery 10 and Vmin is the minimum battery voltage design value. Value.

  In addition to the above-described processing, the battery deterioration information processing unit 33 compares the voltage parameter value acquired by input from the parameter acquisition unit 31 with the allowable voltage value of the storage battery 10 recorded in the storage unit 32 to determine the voltage Even when the parameter value exceeds the allowable voltage value, it is determined that the life of the storage battery is reached, and warning information is output to the display device 40. Also at this time, the display device 40 informs the user that the storage battery is over by, for example, turning on the abnormal lamp 401.

  In the above-described processing, the battery deterioration information processing unit 33 compares the current parameter value acquired last time with the current parameter value acquired from the current parameter acquisition unit 31, and determines whether or not the value has changed by a certain value or more. When it is determined that the current parameter value fluctuates by a certain value or more, the internal resistance value of the storage battery 10 is calculated. However, the battery deterioration information processing unit 33 further defines the fluctuation of the current parameter value flowing into and out of the secondary battery 11 constituting the storage battery 10 immediately before determining that the current parameter value fluctuates more than a certain value. You may make it calculate the internal resistance value of the storage battery 10 only when the state below a value continues more than the fixed time t.

FIG. 5 is a diagram showing an equivalent circuit of the secondary battery.
That is, as shown in this figure, the secondary battery 11 constituting the storage battery 10 includes a capacitor component. Immediately after the current changes, the secondary battery 11 is affected by the voltage Vc of the capacitor component and is detected by ΔV / ΔI. Variations in internal resistance value increase. Therefore, in order to reduce this variation, the storage battery 10 is configured only when a change in the current parameter value flowing into and out of the secondary battery 11 that constitutes the storage battery 10 continues for a predetermined time t or longer. It is desirable to calculate the internal resistance value of the secondary battery 11. Note that the value of the predetermined time t only needs to be larger than the time constant of the CR circuit shown in FIG.
Thereby, the detection accuracy of the internal resistance value R and the deterioration rate γ is further improved, and the accuracy of determination of the deterioration state of the storage battery 10 can be improved.

FIG. 6 is a graph showing the relationship between the operation days of the storage battery and the deterioration rate.
As shown in this figure, as the number of operating days of the storage battery 10 increases, the deterioration rate γ of the storage battery 10 approaches the limit deterioration rate γlimit (lifetime determination value). More specifically, it is known that the relationship between the number of operating days and the deterioration rate is based on the square root rule that the increase in the internal resistance of the storage battery 10 is proportional to the number of charge / discharge cycles and the square root of the operating days. It is expressed by the equation γ = 1 + k√N. N represents the number of operating days, k represents a deterioration acceleration coefficient, and γ = 1.0 at the start of operation.
Here, the deterioration acceleration coefficient k can be calculated from the above square root law equation, the current operation days N, and the deterioration rate γ. Further, using this deterioration acceleration coefficient k and the limit deterioration rate γlimit, the life determination days Nlimit when the deterioration rate becomes γlimit can be calculated. The remaining life days calculation unit 34 of the controller 30 calculates the life determination days Nlimit at a predetermined timing and records it in the storage unit 32. And the remaining life days calculation part 34 records the elapsed days from the time of the operation start of the storage battery 10 at any time, for example in the memory | storage part 32, and the progress currently recorded on the memory | storage part 32 from the calculated lifetime determination days Nlimit. Subtract the number of days to calculate the remaining life days. Then, the remaining life days calculation unit 34 outputs the calculated remaining life days to the display device 40. As a result, the display device 40 displays the remaining life on the monitor.
By such a process, it is possible to notify the user of the estimated calculation life days, and it is possible to more easily prevent occurrence of excessive cost due to early replacement of the storage battery and malfunction due to replacement delay.
In the above-described processing, the life determination days Nlimit is calculated at a predetermined timing, but a plurality of life determination days Nlimit are obtained at predetermined intervals, and the latest life determination days Nlimit is used. The remaining life days indicated by the state of the storage battery 10 may be calculated.

  When the storage battery 10 is composed of a plurality of secondary batteries 11, the deterioration rate is calculated for each secondary battery 11, whether it is a lifetime, or the remaining life days are calculated. You can do it. Alternatively, when a plurality of secondary batteries 11 constituting the storage battery 10 must be replaced at a time, the internal resistance value of the storage battery 10 (each of the two secondary batteries 11 calculated as a group) is calculated. By using the total internal resistance value of the secondary battery 11) and the deterioration rate (average value of the deterioration rate of each secondary battery), it is determined whether or not the battery life is 10 units, and the remaining life days are calculated. Also good.

  The controller 30 and the display device 40 of the battery deterioration detection device 1 described above have a computer system inside. Each process described above is stored in a computer-readable recording medium in the form of a program, and the above process is performed by the computer reading and executing the program. Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

  DESCRIPTION OF SYMBOLS 1 ... Battery deterioration detection apparatus, 2 ... Ammeter, 3 ... Voltmeter, 4 ... Thermometer, 10 ... Storage battery, 11 ... Secondary battery, 20 ... BMS, 21 ... CMU, 23 ... BMU, 30 ... controller, 31 ... parameter acquisition unit, 32 ... storage unit, 33 ... battery deterioration information processing unit, 34 ... remaining life days Calculation unit 35 ... Internal resistance value calculation unit 40 ... Display device 50 ... Electric power load

Claims (7)

Obtaining the current value input / output to / from the storage battery and the voltage value applied to the storage battery, the fluctuation range of the current value when the current value fluctuates more than a certain value, and the fluctuation range of the voltage value at that time An internal resistance value calculation unit for calculating a current internal resistance value of the storage battery using
The current internal resistance value is divided by the internal resistance initial value corresponding to the current temperature of the storage battery, the deterioration rate of the storage battery at the current temperature of the storage battery is calculated, and the storage battery is determined to have a lifetime an internal resistance value Rlimit when a condition to be, for the battery when it is in the open-circuit voltage value V_VOCmax and V_VOCmax the open circuit voltage value when the maximum charging rate of the storage battery that is assumed during operation Voltage value (V_VOCmax + (Icmax x Rlimit)) applied to the storage battery when the current value of charging is the maximum current design value Icmax for the storage battery, and the open circuit voltage when the minimum charging rate of the storage battery is assumed during operation When the value is V_VOCmin and the open circuit voltage is V_VOCmin, the electric current applied to the storage battery when the discharge current value to the storage battery is the maximum current design value Idmax in the storage battery A pressure value (V_VOCmin- (Idmax × Rlimit)) , one of, the internal resistance value Rlimit when outside the allowable voltage value of the battery, and limits the deterioration ratio indicating the ratio of the internal resistance initial value of the battery A battery deterioration information processing unit that compares the deterioration rate of the storage battery at the current temperature and outputs warning information to the monitor device when the deterioration rate is greater than or equal to the limit deterioration rate;
A battery deterioration detection device comprising: The internal resistance value calculation unit is configured to detect the current internal resistance when a change in the current flowing into and out of the storage battery is below a specified value for a predetermined period before the current value fluctuates more than a predetermined value. The battery deterioration detection device according to claim 1, wherein a value is calculated. An internal resistance initial value storage unit that stores an internal resistance initial value at each different temperature of the storage battery, and
The internal resistance value calculation unit calculates an internal resistance initial value corresponding to the acquired temperature of the storage battery based on internal resistance initial values at different temperatures recorded in the internal resistance initial value storage unit. The battery deterioration detection device according to claim 1, wherein the battery deterioration detection device is a battery deterioration detection device. The battery deterioration information processing unit calculates an average of the plurality of calculated deterioration rates, and outputs the average value of the deterioration rates to the monitor device. The battery deterioration detection device according to item. Using the square root rule indicating the relationship between the number of operating days of the storage battery and the deterioration rate, and the deterioration rate in the internal resistance value of the storage battery in a state where the storage battery should be determined to have a lifetime, the storage battery is determined to have a lifetime. Calculating the remaining lifespan days, subtracting the current operation days from the lifespan determination days, and calculating the remaining life days of the storage battery,
5. The battery deterioration detection device according to claim 1, comprising: A battery deterioration detection method for a battery deterioration detection device, comprising:
Obtaining the current value input / output to / from the storage battery and the voltage value applied to the storage battery, the fluctuation range of the current value when the current value fluctuates more than a certain value, and the fluctuation range of the voltage value at that time The current internal resistance value of the storage battery is calculated using
The current internal resistance value is divided by the internal resistance initial value corresponding to the current temperature of the storage battery, the deterioration rate of the storage battery at the current temperature of the storage battery is calculated, and the storage battery is determined to have a lifetime an internal resistance value Rlimit when a condition to be, for the battery when it is in the open-circuit voltage value V_VOCmax and V_VOCmax the open circuit voltage value when the maximum charging rate of the storage battery that is assumed during operation Voltage value (V_VOCmax + (Icmax x Rlimit)) applied to the storage battery when the current value of charging is the maximum current design value Icmax for the storage battery, and the open circuit voltage when the minimum charging rate of the storage battery is assumed during operation When the value is V_VOCmin and the open circuit voltage is V_VOCmin, the electric current applied to the storage battery when the discharge current value to the storage battery is the maximum current design value Idmax in the storage battery A pressure value (V_VOCmin- (Idmax × Rlimit)) , one of, the internal resistance value Rlimit when outside the allowable voltage value of the battery, and limits the deterioration ratio indicating the ratio of the internal resistance initial value of the battery A battery deterioration detection method comprising: comparing a deterioration rate of the storage battery at the current temperature and outputting warning information to a monitor device when the deterioration rate is equal to or greater than the limit deterioration rate. The battery deterioration detection computer
Obtaining the current value input / output to / from the storage battery and the voltage value applied to the storage battery, the fluctuation range of the current value when the current value fluctuates more than a certain value, and the fluctuation range of the voltage value at that time An internal resistance value calculation process for calculating a current internal resistance value of the storage battery using
The current internal resistance value is divided by the internal resistance initial value corresponding to the current temperature of the storage battery, the deterioration rate of the storage battery at the current temperature of the storage battery is calculated, and the storage battery is determined to have a lifetime an internal resistance value Rlimit when a condition to be, for the battery when it is in the open-circuit voltage value V_VOCmax and V_VOCmax the open circuit voltage value when the maximum charging rate of the storage battery that is assumed during operation Voltage value (V_VOCmax + (Icmax x Rlimit)) applied to the storage battery when the current value of charging is the maximum current design value Icmax for the storage battery, and the open circuit voltage when the minimum charging rate of the storage battery is assumed during operation When the value is V_VOCmin and the open circuit voltage is V_VOCmin, the electric current applied to the storage battery when the discharge current value to the storage battery is the maximum current design value Idmax in the storage battery A pressure value (V_VOCmin- (Idmax × Rlimit)) , one of, the internal resistance value Rlimit when outside the allowable voltage value of the battery, and limits the deterioration ratio indicating the ratio of the internal resistance initial value of the battery Battery deterioration information processing for comparing the deterioration rate of the storage battery at the current temperature and outputting warning information to the monitor device when the deterioration rate is equal to or greater than the limit deterioration rate;
A program characterized by functioning as

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