JP2015210182A - Performance estimation device and performance estimation method of lead acid storage battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a performance estimation device and a performance estimation method of lead acid storage battery, improving an estimation accuracy of performances of the lead acid storage battery.SOLUTION: A performance estimation device 10 of a lead acid storage battery comprises: an estimation part 11 that estimates a parameter and an open circuit voltage of the lead acid storage battery based on a terminal voltage and charge/discharge current of the lead acid storage battery; an internal resistance calculation part 13 calculating internal resistance of the lead acid storage battery using the parameter; and a battery performance calculation part 16 that determines that a sum of an open circuit voltage reduction amount of the lead acid storage battery generated when the lead acid storage battery is discharged by current I for a time T and a voltage drop amount due to the internal resistance is equal to a difference between the open circuit voltage and a predetermined discharge final voltage, and that calculates the current I or the time T. When one of the current I and the time T is determined to a predetermined value, the battery performance calculation part 16 calculates the other of the current I and the time T.

Description

  The present invention relates to a performance estimation device and a performance estimation method for estimating the performance of a lead storage battery.

  Conventionally, as a standard indicating the performance (capacity) of a lead storage battery used for starting an internal combustion engine of a vehicle such as an automobile, for example, in JIS, cold cranking current (CCA: Cold Cranking Ampere), reserve capacity (RC: Reserve) Capacity) and 5 hour rate capacity are specified. These standard values are used not only as an index for evaluating the performance of a lead-acid battery when it is new, but also as an index for evaluating performance degradation due to the use of the lead-acid battery. For example, it is desirable to measure these values periodically in order to determine the replacement time of the lead storage battery. For this reason, it is desirable to simply measure these values in a room temperature environment. For example, in Patent Document 1, experimental data indicating the relationship between the internal resistance and the performance value (for example, CCA) of the lead storage battery is stored in advance, and lead is generated according to the internal resistance calculated based on the voltage and current of the lead storage battery. A method for determining the performance value of a storage battery is described.

Special table 2007-525354 gazette

  However, in the prior art, the accuracy of judging the performance of the lead storage battery may not always be sufficient. For example, the relationship between the internal resistance and the performance value of the lead storage battery changes due to the deterioration of the lead storage battery over time. In addition, the relationship between the internal resistance of the lead storage battery and the performance value varies depending on individual differences in the performance of the lead storage battery. For this reason, the relationship between the internal resistance and the performance value indicated by the information stored in advance does not necessarily match the current relationship between the internal resistance and the performance value of the lead storage battery, and the accuracy of judging the performance of the lead storage battery is reduced. There was something to do.

  The objective of this invention made | formed in view of this situation is providing the performance estimation apparatus and performance estimation method of a lead storage battery which improve the estimation precision of the performance of a lead storage battery.

In order to solve the above-mentioned problem, the performance estimation device for a lead-acid battery according to the first invention comprises:
An estimation unit that estimates the parameters and open circuit voltage of the lead storage battery based on the terminal voltage and charge / discharge current of the lead storage battery, and
An internal resistance calculator for calculating the internal resistance of the lead-acid battery using the parameters;
The sum of the decrease in the open-circuit voltage of the lead-acid battery and the voltage drop due to the internal resistance that occurs when the lead-acid battery is discharged for a time T with the current I is equal to the difference between the open-circuit voltage and a predetermined discharge end voltage. A battery performance calculation unit for calculating the current I or the time T,
The battery performance calculation unit calculates the other of the current I and the time T when one of the current I and the time T is set to a predetermined value.

Moreover, in the performance estimation device of the lead storage battery according to the second invention,
The predetermined discharge end voltage is 7.2V, and the time T is set to 30 seconds.
The battery performance calculation unit calculates the current I.

Moreover, in the performance estimation device of the lead storage battery according to the third invention,
The predetermined discharge end voltage is 10.5V, and the current I is set to 25A.
The battery performance calculation unit calculates the time T.

Moreover, in the performance estimation device of the lead storage battery according to the fourth invention,
The predetermined end-of-discharge voltage is 10.5V, and the current I is determined as a 5-hour rate current of the lead acid battery,
The battery performance calculation unit calculates the time T.

Moreover, the performance estimation device for a lead storage battery according to the fifth invention is:
A resistance correction unit that corrects the resistance included in the parameter with temperature is further provided.

Moreover, in the performance estimation device for a lead storage battery according to the sixth invention,
The internal resistance calculation unit calculates the internal resistance by determining the internal resistance of the lead-acid battery as a function having a predetermined time constant.

Moreover, the performance estimation device of the lead storage battery according to the seventh invention is:
An open-circuit voltage correction unit that corrects the open-circuit voltage with temperature is further provided.

Moreover, the performance estimation device for a lead storage battery according to the eighth invention is:
Further comprising a health estimation unit that estimates the health of the lead-acid battery based on the parameters;
The battery performance calculation unit corrects the decrease in the open circuit voltage using the soundness level.

Moreover, in the performance estimation apparatus of the lead storage battery according to the ninth invention,
The battery performance calculation unit calculates the soundness of the lead storage battery based on a comparison between the calculated current I and a predetermined reference value, or based on a comparison between the calculated time T and a predetermined reference value. The health level of the lead storage battery is calculated.

Moreover, the performance estimation method of the lead storage battery according to the tenth invention is as follows:
Estimating the parameters and open circuit voltage of the lead storage battery based on the terminal voltage and charge / discharge current of the lead storage battery, respectively;
Calculating the internal resistance of the lead acid battery using the parameters;
The sum of the decrease in the open-circuit voltage of the lead-acid battery and the voltage drop in the internal resistance that occurs when the lead-acid battery is discharged for a time T with current I is equal to the difference between the open-circuit voltage and a predetermined discharge end voltage. And calculating the current I or the time T,
In the step of calculating the current I or the time T, when one of the current I and the time T is set to a predetermined value, the other of the current I and the time T is calculated. To do.

  According to the performance estimation device for a lead storage battery according to the first invention, since the current I or time T is calculated based on the current state of the lead storage battery, the influence of individual differences in battery performance or aging deterioration is reduced, The estimation accuracy of the performance of the lead storage battery can be improved. Further, since the current I or the time T can be calculated while the vehicle is running, the performance of the lead storage battery can be evaluated by a simple method without taking the lead storage battery from the vehicle for testing, for example.

  Moreover, according to the performance estimation apparatus of the lead storage battery which concerns on 2nd invention, the CCA test defined by JIS can be implemented by a simple method, and the cold cranking current which is the performance of a lead storage battery can be evaluated.

  Moreover, according to the performance estimation apparatus of the lead storage battery which concerns on 3rd invention, the RC test defined by JIS can be implemented by a simple method, and the reserve capacity which is the performance of a lead storage battery can be evaluated.

  Moreover, according to the performance estimation apparatus of the lead storage battery which concerns on 4th invention, the 5 hour rate capacity test defined by JIS can be implemented by a simple method, and the 5 hour rate capacity which is the performance of a lead storage battery can be evaluated. is there.

  Moreover, according to the performance estimation device for a lead storage battery according to the fifth aspect of the invention, the temperature dependence of the resistance included in the parameter is corrected, so that the estimation accuracy of the internal resistance R of the lead storage battery is improved, and the performance of the lead storage battery is improved. The estimation accuracy can be further improved.

  Moreover, according to the performance estimation device for a lead storage battery according to the sixth aspect of the invention, the estimation accuracy of the internal resistance R that changes with time due to a transient phenomenon is improved, so that the estimation accuracy of the performance of the lead storage battery can be further improved. .

  In addition, according to the performance estimation device for a lead storage battery according to the seventh invention, the temperature dependence of the open circuit voltage OCV is corrected. Therefore, the estimation accuracy of the open circuit voltage OCV of the lead storage battery is improved, and the performance of the lead storage battery is estimated. The accuracy can be further improved.

Moreover, according to the performance estimation device for a lead storage battery according to the eighth aspect of the invention, since the open circuit voltage decrease ΔV ₁ is corrected using the estimated soundness SOH, the estimation accuracy of the open circuit voltage decrease ΔV ₁ is improved, The estimation accuracy of the performance of the lead storage battery can be further improved.

  In addition, according to the performance estimation device for a lead storage battery according to the ninth aspect, the soundness SOH of the lead storage battery can be estimated based on a comparison between the calculated current I or time T and a predetermined reference value. Further, since the current I or the time T can be calculated while the vehicle is running, for example, the soundness SOH of the lead storage battery can be evaluated by a simple method without removing the lead storage battery from the vehicle for testing.

  In addition, according to the performance estimation method for a lead storage battery according to the tenth invention, the current I or time T is calculated based on the current state of the lead storage battery, thereby reducing the influence of individual differences in battery performance or deterioration over time. In addition, the estimation accuracy of the performance of the lead storage battery can be improved. Further, since the current I or the time T can be calculated while the vehicle is running, the performance of the lead storage battery can be evaluated by a simple method without taking the lead storage battery from the vehicle for testing, for example.

It is a functional block diagram of the performance estimation apparatus of the lead acid battery which concerns on Embodiment 1 of this invention. It is a figure which shows the example of the equivalent circuit model of a lead acid battery. It is a figure explaining the relationship between resistance of lead acid battery, and temperature. It is a figure explaining the change of internal resistance of a lead acid battery. It is a figure explaining the change of the terminal voltage by discharge of a lead acid battery. It is a flowchart which shows the operation example of the performance estimation apparatus of the lead acid battery of FIG. It is a functional block diagram of the performance estimation apparatus of the lead acid battery which concerns on Embodiment 2 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
First, the performance estimation apparatus for a lead storage battery according to Embodiment 1 of the present invention will be described. The performance estimation device for a lead storage battery according to Embodiment 1 is provided in a vehicle such as an automobile, for example. The performance estimation device evaluates the performance of the lead storage battery provided in the vehicle based on, for example, any one of the CCA test standard, the RC test standard, and the 5-hour rate capacity test standard defined by JIS. Conduct a performance evaluation test.

Here, the above-described test defined by JIS will be specifically described. The CCA test is a test for evaluating a discharge current (cold cranking current) at which the voltage of the lead storage battery is 7.2 V after the start of constant current discharge of the lead storage battery at a temperature of -18 ° C. The RC test is a test for evaluating the duration (reserved capacity) when a lead storage battery is discharged at a current of 25 A to a discharge end voltage of 10.5 V when the temperature of the lead storage battery is 25 ° C. In the 5-hour rate test, when the temperature of the lead storage battery was 25 ° C., the duration when the lead storage battery was discharged to a discharge end voltage of 10.5 V with a 5-hour rate current was measured, and the time was multiplied by the 5-hour rate current. This is a test for evaluating the capacity (5-hour rate capacity). That is, all of the above-described tests are tests for evaluating the current I or the time T when the lead storage battery is discharged for a time T with a current I (constant current) to a predetermined end-of-discharge voltage V _e at a predetermined temperature.

  The configuration of the lead storage battery performance estimation device will be described. As shown in FIG. 1, the performance estimation device 10 for a lead storage battery includes an estimation unit 11, a resistance correction unit 12, an internal resistance calculation unit 13, an open-circuit voltage correction unit 14, a storage unit 15, and a battery performance calculation unit. 16. The estimation unit 11, the resistance correction unit 12, the internal resistance calculation unit 13, the open-circuit voltage correction unit 14, and the battery performance calculation unit 16 may be configured by an information processing device such as an in-vehicle microcomputer having a processor and a memory, for example. it can. Moreover, the memory | storage part 15 can be comprised with memory | storage devices, such as a vehicle-mounted memory, for example.

The estimation unit 11 acquires measured values of the charge / discharge current i and the terminal voltage v of the lead storage battery when the vehicle is traveling. The charge / discharge current i and the terminal voltage v can be obtained from, for example, a current sensor and a voltage sensor provided in the vehicle. Based on the charge / discharge current i and the terminal voltage v, the estimation unit 11 sequentially estimates parameters of an equivalent circuit model of the lead storage battery and an open circuit voltage OCV (Open Circuit Voltage) using an adaptive filter such as a Kalman filter. In the first embodiment, the primary Foster-type RC ladder circuit shown in FIG. 2 is adopted as an equivalent circuit model. In such a case, the parameters to be estimated are the resistance R ₀ , the resistance R ₁ , and the capacitance C ₁ . As the equivalent circuit model of the lead-acid battery, any mathematical model representing the inside of the lead battery can be adopted. For example, an n-th order Foster-type RC ladder circuit or an n-th order Cowell-type RC ladder circuit may be employed.

Here, the primary Foster-type RC ladder circuit shown in FIG. 2 will be described. The primary Foster-type RC ladder circuit is a circuit in which a capacitor C ₀ , a resistor R _0, and a parallel circuit of the resistor R ₁ and the capacitor C ₁ are connected in series. The voltage across the capacitor C ₀ is the open circuit voltage OCV. The resistance R ₀ indicates an ohmic resistance such as the resistance of the electrolytic solution of the lead storage battery and the resistance of connection. Resistor R ₁ represents a reaction resistance in the charge transfer process and / or diffusion process of lead-acid batteries. Capacitance C ₁ indicates the capacitance due to the electric double layer.

The resistance correction unit 12 illustrated in FIG. 1 acquires the temperature tmp of the lead storage battery. The temperature tmp can be acquired from, for example, a temperature sensor provided in the vehicle. The resistance correction unit 12 corrects the resistance (for example, the resistance R ₁ ) included in the parameters of the lead storage battery estimated by the estimation unit 11 based on the temperature tmp with the temperature. Details will be described below.

The resistance correction unit 12 stores in advance correspondence information indicating a correspondence relationship between the resistance R _{1 of the} primary Foster-type RC ladder circuit and the temperature tmp of the lead storage battery. Generally, the resistance R ₁ and the temperature tmp have a correspondence relationship in which the value of the resistance R ₁ increases as the temperature tmp decreases as shown in FIG. The correspondence information indicating the correspondence relationship can be calculated in advance by experiments or simulations.

The resistance correction unit 12 corrects the value of the resistance R ₁ estimated by the estimation unit 11 to a value corresponding to a predetermined temperature based on the acquired temperature tmp of the lead storage battery and correspondence information. The predetermined temperature is determined according to the standard of the test to be performed. For example, the predetermined temperature is set to −18 ° C. defined by JIS when the CCA test is performed. The predetermined temperature is set to 25 ° C. defined by JIS when the RC test or the 5-hour rate capacity test is performed.

The internal resistance calculation unit 13 shown in FIG. 1 acquires parameters (resistance R ₀ , resistance R ₁ , and capacity C ₁ ) of the lead storage battery. The internal resistance calculator 13 calculates the internal resistance (synthetic resistance) R of the lead storage battery based on the acquired parameter.

  Preferably, the internal resistance calculator 13 determines the internal resistance R of the lead storage battery as a function having a predetermined time constant, and calculates the internal resistance R. Details will be described below.

FIG. 4 is a diagram showing the time change of the internal resistance R of the primary Foster-type RC ladder circuit. The internal resistance R when the time T elapses from the start of discharge is expressed by Equation (1) using the resistance R ₀ , the resistance R ₁ , the capacitance C ₁ , and the time T.
_{R = R 0 + R 1 {} 1-e -T / (R1C1)} (1)
The second term of the right side of equation (1), the resistance R ₁ and shows the resistance of the parallel circuit of the capacitor C _1, is represented by a function having a time constant tau = R ₁ C _1.

  The internal resistance calculation unit 13 calculates the internal resistance R according to the equation (1). For example, when the CCA test is performed, the internal resistance calculation unit 13 sets time T = 30 seconds based on JIS regulations, and calculates the internal resistance R when 30 seconds have elapsed from the start of discharge of the lead storage battery. Further, when performing the RC test or the 5-hour rate capacity test, the internal resistance calculation unit 13 may calculate the internal resistance R by the equation (1) using the time T estimated in the previous evaluation test.

  The open circuit voltage correction | amendment part 14 shown in FIG. 1 acquires temperature tmp of a lead acid battery. The open-circuit voltage correction unit 14 corrects the open-circuit voltage OCV of the lead storage battery estimated by the estimation unit 11 with the temperature based on the temperature tmp. Details will be described below.

In general, the open circuit voltage OCV of a lead storage battery has temperature dependence, and the value of the open circuit voltage OCV decreases as the temperature tmp increases. And the open-circuit voltage OCV ₁ at temperatures tmp _1, the relationship between the open circuit voltage OCV ₂ at temperatures tmp ₂ is represented by example equation (2).
OCV ₂ = OCV ₁ + N {0.0007 (tmp ₁ −tmp ₂ )] (2)
Here, N is the number of cells of the lead storage battery. The open-circuit voltage correction unit 14 determines the acquired temperature tmp as tmp ₁ and the open-circuit voltage OCV estimated by the estimation unit 11 as OCV ₁ , and calculates the open-circuit voltage OCV ₂ at a predetermined temperature tmp ₂ using Equation (2). To do. The predetermined temperature tmp ₂ is determined according to the standard of the test to be performed. For example, when the CCA test is performed, the predetermined temperature tmp ₂ is set to −18 ° C. defined by JIS. The predetermined temperature tmp ₂ is set to 25 ° C. defined by JIS when the RC test or the 5-hour rate capacity test is performed. The open-circuit voltage correction unit 14 determines the calculated OCV ₂ as the corrected open-circuit voltage OCV.

The memory | storage part 15 memorize | stores the information regarding a lead storage battery beforehand. The information on the lead storage battery includes, for example, the value of the terminal voltage change amount V _diff / DC per charge and the value of the 5-hour rate current I _5h of the lead storage battery. DC is the design capacity of the lead acid battery. As the terminal voltage change amount V _diff / DC per charge and the 5-hour rate current I _5h , values determined in advance by experiment or simulation may be used, or nominal values may be used.

Preferably, the storage unit 15 stores in advance the terminal voltage change amount V _diff / DC per charge at the corresponding temperature in association with a plurality of predetermined temperatures. The predetermined temperature is a temperature defined by a standard for each test to be performed. For example, the storage unit 15 stores in advance terminal voltage change amounts V _diff / DC per charge corresponding to −18 ° C. and 25 ° C., respectively.

The battery performance calculation unit 16 acquires the internal resistance R from the internal resistance calculation unit 13, the open circuit voltage OCV from the open circuit voltage correction unit 14, and the terminal voltage change amount V _diff / DC per charge from the storage unit 15. Preferably, the terminal voltage change amount V _diff / DC per charge acquired by the battery performance calculation unit 16 is a value corresponding to the temperature of the lead storage battery defined by the standard of the test to be performed. The battery performance calculation unit 16 calculates the current I or the time T when the lead storage battery is discharged for the time T with the current I to the end-of-discharge voltage V _e using the acquired information. Details will be described below.

The terminal voltage of the lead acid battery decreases as the discharge proceeds. The solid line shown in FIG. 5 shows the time change of the terminal voltage of the lead storage battery when the lead storage battery is discharged for a time T with the current I up to the end-of-discharge voltage V _e . The dashed-dotted line shown in FIG. 5 shows the time change of the terminal voltage when the internal resistance R of the lead storage battery is set to zero. The decrease in the terminal voltage that occurs from the start of discharge until the time T elapses is due to the decrease ΔV _{1 in the} open circuit voltage OCV caused by the discharge of the charge stored in the capacitor C ₀ and the current I flowing through the internal resistance R. This is considered to be the sum of the generated voltage drop ΔV ₂ .

The open circuit voltage decrease ΔV ₁ is expressed by Equation (3).

Further, the voltage drop ΔV ₂ generated by the internal resistance R is expressed by the equation (4).
ΔV ₂ = RI (4)

Here, the terminal voltage when the charge / discharge current is zero is equal to the open-circuit voltage OCV of the lead storage battery. For this reason, the value of the terminal voltage immediately before the start of discharge is set to the open circuit voltage OCV corrected by the open circuit voltage correction unit 14. In such a case, the sum of the open circuit voltage decrease ΔV ₁ and the voltage drop ΔV ₂ is equal to the difference between the open circuit voltage OCV and the discharge end voltage V _e . That is, Expression (5) is established.
OCV−V _e = ΔV ₁ + ΔV ₂ (5)

In Expressions (3) to (5), the internal resistance R, the open circuit voltage OCV, and the terminal voltage change amount V _diff / DC per charge are values acquired by the battery performance calculation unit 16, respectively. Further, as the discharge end voltage V _e and the current I or the time T, values determined by the standard of the test to be performed are used. Hereinafter, the calculation process of the current I or time T performed by the battery performance calculation unit 16 will be specifically described for each test to be performed.

Ｉ＝（ＯＣＶ−７．２）／（Ｒ＋Ａ） （７）
ここで、Ａ＝３０・Ｖ_diff／ＤＣとおいた。 (CCA test)
When performing the CCA test, the battery performance calculation unit 16 sets time T = 30 seconds and discharge end voltage V _e = 7.2 V in accordance with JIS regulations, and is based on Formula (3) -Formula (5). The current I is calculated by (6) and Equation (7).

I = (OCV−7.2) / (R + A) (7)
Here, A = 30 · V _diff / DC.

Ｔ＝（ＯＣＶ−１０．５−２５Ｒ）／Ｂ （９）
ここで、Ｂ＝２５・Ｖ_diff／ＤＣとおいた。 (RC test)
When performing the RC test, the battery performance calculation unit 16 sets the current I = 25 A and the discharge end voltage V _e = 10.5 V according to the JIS regulations, and the formula (3) −the formula based on the formula (5) ( The time T is calculated by 8) and equation (9).

T = (OCV-10.5-25R) / B (9)
Here, B = 25 · V _diff / DC.

Ｔ＝（ＯＣＶ−１０．５−ＲＩ_5h）／Ｃ （１１）
ここで、Ｃ＝Ｉ_5h・Ｖ_diff／ＤＣとおいた。好適には、電池性能演算部１６は、演算した時間Ｔに５時間率電流Ｉ_5hを乗じて５時間率容量を更に演算する。 (5-hour rate capacity test)
The battery performance calculation unit 16 acquires the value of the 5-hour rate current I _5h of the lead storage battery from the storage unit 15 when performing the 5-hour rate capacity test. The battery performance calculation unit 16 determines the current I = I _5h and the discharge end voltage V _e = 10.5V in accordance with JIS regulations, and formulas (10) and (11) based on formulas (3)-(5). ) To calculate the time T.

T = (OCV-10.5−RI _5h ) / C (11)
Here, C = I _5h · V _diff / DC. Preferably, the battery performance calculation unit 16 further calculates the 5-hour rate capacity by multiplying the calculated time T by the 5-hour rate current I _5h .

  Next, the lead storage battery performance evaluation test process performed by the lead storage battery performance estimation apparatus 10 will be described with reference to the flowchart of FIG. 6. This process is performed, for example, when the vehicle including the lead storage battery and the performance estimation device 10 is traveling. FIG. 6 illustrates a process for performing a CCA test.

First, the estimation part 11 acquires the charging / discharging current i and terminal voltage v of a lead storage battery, and estimates the parameter and open circuit voltage OCV of a lead storage battery (step S100). The parameters are, for example, a resistor R ₀ , a resistor R ₁ , and a capacitor C ₁ included in the primary Foster-type RC ladder circuit.

Next, the resistance correction unit 12 acquires the temperature tmp of the lead storage battery, and corrects the resistance R ₁ with the temperature among the parameters estimated in step S101 (step S101). Specifically, the resistance correction unit 12 corrects the estimated resistance R ₁ to a resistance value at −18 ° C.

Next, the internal resistance calculator 13 calculates the internal resistance R based on the resistance R ₀ and the capacitance C ₁ estimated in step S100 and the resistance R ₁ corrected in step S101 (step S102). Preferably, the internal resistance calculation unit 13 sets the time T = 30 seconds, and calculates the internal resistance R when 30 seconds have elapsed from the start of discharge of the lead storage battery according to Equation (1).

  Next, the open-circuit voltage correction unit 14 acquires the temperature tmp of the lead storage battery, and corrects the open-circuit voltage OCV estimated in step S100 with the temperature (step S103). Specifically, the open-circuit voltage correction unit 14 corrects the estimated open-circuit voltage OCV to a voltage value at −18 ° C.

Then, the battery performance calculation unit 16 acquires the terminal voltage change amount V _diff / DC per charge of the lead storage battery from the storage unit 15. The battery performance calculation unit 16 uses the acquired terminal voltage change amount V _diff / DC per charge, the internal resistance R calculated in step S102, and the open-circuit voltage OCV corrected in step S103, to provide a constant current for the lead storage battery. A current I at which the voltage at the 30th second from the start of discharge becomes 7.2 V is calculated by the equation (7) (step S104).

  According to the performance estimation device 10 for a lead storage battery according to the first embodiment described above, the estimation unit 11 uses parameters and open circuit voltage OCV based on the charge / discharge current i and the terminal voltage v of the lead storage battery actually provided in the vehicle. Is estimated. The battery performance calculator 16 calculates the current I or time T when discharging the lead storage battery based on the estimated parameter and the open circuit voltage OCV. As described above, since the current I or time T is calculated based on the current state of the lead storage battery, it is possible to reduce the influence of individual differences in battery performance or aging deterioration, and to improve the estimation accuracy of the performance of the lead storage battery. . Further, since the current I or the time T can be calculated while the vehicle is running, the performance of the lead storage battery can be evaluated by a simple method without taking the lead storage battery from the vehicle for testing, for example.

  Moreover, according to the performance estimation apparatus 10 of a lead storage battery, for example, a CCA test, an RC test, and a 5-hour rate capacity test defined by JIS are performed by a simple method, and the cold cranking current that is the performance of the lead storage battery, Reserve capacity and 5 hour rate capacity can be evaluated.

  Moreover, according to the performance estimation apparatus 10 of a lead storage battery, the resistance correction unit 12 corrects the resistance included in the parameter estimated by the estimation unit 11 with the temperature. Generally, the resistance in the charge transfer process or diffusion process of a lead storage battery has temperature dependence. Since the temperature dependency is corrected by the resistance correction unit 12, the estimation accuracy of the internal resistance R of the lead storage battery can be improved, and the estimation accuracy of the performance of the lead storage battery can be further improved.

  Further, the internal resistance calculation unit 13 calculates the internal resistance R by setting the internal resistance R of the lead storage battery as a function having a predetermined time constant. Generally, the resistance in the charge transfer process and the diffusion process of a lead storage battery changes with time due to a transient phenomenon when discharge is started. Since the estimation accuracy of the internal resistance R is improved by the internal resistance calculation unit 13, the estimation accuracy of the performance of the lead storage battery can be further improved.

  Moreover, according to the performance estimation apparatus 10 of lead acid battery, the open circuit voltage correction | amendment part 14 correct | amends the open circuit voltage OCV which the estimation part 11 estimated with temperature. Generally, the open circuit voltage OCV of a lead storage battery has temperature dependence. Since the temperature dependency is corrected by the resistance correction unit 12, the estimation accuracy of the open-circuit voltage OCV of the lead storage battery can be improved, and the estimation accuracy of the performance of the lead storage battery can be further improved.

(Embodiment 2)
Next, a performance estimation device for a lead storage battery according to Embodiment 2 of the present invention will be described. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. The performance estimation device for a lead storage battery according to Embodiment 2 differs from Embodiment 1 in that it further includes a soundness estimation unit.

  As shown in FIG. 7, the performance estimation device 100 for a lead storage battery according to the second embodiment includes an estimation unit 11, a resistance correction unit 12, an internal resistance calculation unit 13, an open-circuit voltage correction unit 14, and a storage unit 15. And a battery performance calculation unit 160 and a soundness estimation unit 170.

The soundness level estimation unit 170 stores in advance correspondence information indicating a correspondence relationship between the internal resistance R of the lead acid battery and the soundness level SOH (State Of Health) of the lead acid battery. The correspondence information can be calculated in advance by experiment or simulation. The soundness level SOH is an index of the degree of deterioration of the lead storage battery. The soundness level SOH is expressed by the formula (12) using, for example, a full charge capacity FCC (Full Charge Capacity) and a design capacity DC of a lead storage battery.
SOH = FCC / DC (12)

The soundness estimation unit 170 acquires the parameters of the lead storage battery. The parameters are, for example, the resistance R ₀ , the resistance R ₁ , and the capacitance C ₁ of the primary Foster-type RC ladder circuit. The acquired resistance R ₁ may be a value estimated by the estimation unit 11 or a value corrected by the resistance correction unit 12. The soundness level estimation unit 170 calculates the internal resistance R of the lead storage battery based on the acquired parameter. The soundness estimation unit 170 estimates the soundness SOH of the lead storage battery by extracting the soundness SOH corresponding to the internal resistance R from the correspondence information.

The battery performance calculation unit 160 calculates the internal resistance R from the internal resistance calculation unit 13, the open circuit voltage OCV from the open circuit voltage correction unit 14, the terminal voltage change amount V _diff / DC per charge from the storage unit 15, and the soundness estimation. The soundness level SOH is acquired from the unit 170.

The battery performance calculation unit 160 corrects the open circuit voltage decrease ΔV ₁ calculated by the equation (3) by multiplying the inverse of the soundness level SOH. In other words, the battery performance calculation unit 160 calculates the corrected open-circuit voltage decrease ΔV _{1 according} to the equation (13) instead of the equation (3).

The battery performance calculation unit 160 calculates the current I or the time T when the lead storage battery is discharged for the time T with the current I to the end-of-discharge voltage V _e based on the equations (13), (4), and (5). Calculate. Since the calculation process of the current I or time T performed by the battery performance calculation unit 16 for each test to be performed is the same as that of the first embodiment, the description thereof is omitted.

According to the lead storage battery performance estimation device 100 according to Embodiment 2 described above, the battery performance calculation unit 160 corrects the open circuit voltage decrease ΔV ₁ using the soundness level SOH estimated by the soundness level estimation unit 170. . With this correction, the open circuit voltage decrease ΔV1 is calculated using the full charge capacity FCC estimated based on the current state of the lead storage battery, instead of the design capacity DC, as shown in Expression (13). For this reason, it is possible to improve the estimation accuracy of the open circuit voltage decrease ΔV ₁ and further improve the estimation accuracy of the performance of the lead storage battery.

(Modification)
Next, a performance estimation device for a lead storage battery according to a modification of the embodiment of the present invention will be described. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. The performance estimation device for a lead storage battery according to the modified example is different from the first embodiment in that the soundness SOH of the lead storage battery is further calculated.

  Similar to the first embodiment, the performance estimation device 10 for a lead storage battery according to the modification includes an estimation unit 11, a resistance correction unit 12, an internal resistance calculation unit 13, an open-circuit voltage correction unit 14, and a storage unit 15. The battery performance calculation unit 16 is provided.

The battery performance calculation unit 16 calculates the soundness SOH of the lead storage battery based on a comparison between the current I or time T calculated in the same manner as in the first embodiment and a reference value determined according to the test to be performed. . The reference value is determined, for example, as an actual standard value of current I or time T determined by JIS for each test to be performed. For example, in the case of a lead storage battery of the type 34B17L, the reference value I _CCA in the CCA test is set to 279A, which is an actual standard value of the cold cranking current. In addition, the reference value T _RC in the RC test is set to 47 minutes, which is a standard value of reserve capacity. Further, the reference value C _5h at 5 hour rate capacity test is defined in a merit standard value of 5-hour rate capacity 27Ah. The reference value may be set to the value of the current I or the time T calculated by the battery performance calculation unit 16 using, for example, a new lead-acid battery, in addition to the ability standard value determined by JIS.

Specifically, when the CCA test is performed, the battery performance calculation unit 16 calculates the soundness level SOH by using the calculated current I and the reference value I _{CCA according} to the equation (14).
SOH = (I / I _CCA ) × 100 (14)

In addition, when performing the RC test, the battery performance calculation unit 16 calculates the soundness level SOH according to the equation (15) using the calculated time T and the reference value T _RC .
SOH = (T / T _RC ) × 100 (15)

In addition, when performing the 5-hour rate capacity test, the battery performance calculation unit 16 calculates the soundness degree SOH according to the equation (16) using the 5-hour rate current I _5h , the calculated time T, and the reference value C _5h. To do.
SOH = (I _5h × T / C _5h ) × 100 (16)

  According to the performance estimation device 10 for a lead storage battery according to the modified example of the above-described embodiment, based on a comparison between the current I or time T calculated by the battery performance calculation unit 16 and a predetermined reference value, The degree of soundness SOH can be estimated. Further, since the current I or the time T can be calculated while the vehicle is running, for example, the soundness SOH of the lead storage battery can be evaluated by a simple method without removing the lead storage battery from the vehicle for testing.

  Although the present invention has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various modifications and corrections based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention. For example, functions and the like included in each means and each step can be rearranged so as not to be logically contradictory, and a plurality of means and steps can be combined into one or divided. .

  Further, the lead storage battery performance estimation devices 10 and 100 may start processing of the lead storage battery performance evaluation test when the lead storage battery is in a fully charged state and the vehicle starts running. In this way, as will be described below, the estimation accuracy of the current I or time T can be further improved. In the implementation of the CCA test, the RC test, and the 5 hour rate capacity test, JIS stipulates that the state of the lead-acid battery is a fully charged state. By executing the performance evaluation test process of the lead storage battery when the vehicle starts running when the lead storage battery is in a fully charged state, the value of the open circuit voltage OCV estimated by the estimation unit 11 is the value of the lead storage battery in the fully charged state. It approaches the value of the open circuit voltage. Thus, since the performance estimation apparatus 10 of a lead storage battery estimates the performance of a lead storage battery on the conditions close | similar to the test conditions defined by JIS, the estimation precision of the electric current I or time T can further be improved.

  Moreover, in Embodiment 2 mentioned above, although the soundness estimation part 170 calculates the internal resistance R by acquiring the parameter of lead acid battery, you may acquire the internal resistance R which the internal resistance calculation part 13 calculated. .

  Moreover, although the performance estimation apparatus 10 of the lead storage battery which concerns on the modification mentioned above was demonstrated as what is the structure similar to the performance estimation apparatus 10 of Embodiment 1, similarly to Embodiment 2, the estimation part 11 and The resistance correction unit 12, the internal resistance calculation unit 13, the open-circuit voltage correction unit 14, the storage unit 15, the battery performance calculation unit 160, and the soundness estimation unit 170 may be used.

DESCRIPTION OF SYMBOLS 10,100 Performance estimation apparatus 11 Estimation part 12 Resistance correction part 13 Internal resistance calculation part 14 Open-circuit voltage correction part 15 Memory | storage part 16,160 Battery performance calculation part 170 Soundness estimation part

Claims (10)

An estimation unit that estimates the parameters and open circuit voltage of the lead storage battery based on the terminal voltage and charge / discharge current of the lead storage battery, and
An internal resistance calculator for calculating the internal resistance of the lead-acid battery using the parameters;
The sum of the decrease in the open-circuit voltage of the lead-acid battery and the voltage drop due to the internal resistance that occurs when the lead-acid battery is discharged for a time T with the current I is equal to the difference between the open-circuit voltage and a predetermined discharge end voltage. A battery performance calculation unit for calculating the current I or the time T,
The battery performance calculation unit is a performance estimation device for a lead storage battery, which calculates one of the current I and the time T when one of the current I and the time T is set to a predetermined value. It is a performance estimation apparatus of the lead acid battery according to claim 1,
The predetermined discharge end voltage is 7.2V, and the time T is set to 30 seconds.
The battery performance calculation unit is a lead storage battery performance estimation device that calculates the current I. It is a performance estimation apparatus of the lead acid battery according to claim 1,
The predetermined discharge end voltage is 10.5V, and the current I is set to 25A.
The battery performance calculation unit is a lead storage battery performance estimation device that calculates the time T. It is a performance estimation apparatus of the lead acid battery according to claim 1,
The predetermined end-of-discharge voltage is 10.5V, and the current I is determined as a 5-hour rate current of the lead acid battery,
The battery performance calculation unit is a lead storage battery performance estimation device that calculates the time T. It is the performance estimation apparatus of the lead acid battery as described in any one of Claims 1 thru | or 4, Comprising:
The performance estimation apparatus of a lead storage battery further provided with the resistance correction | amendment part which correct | amends the resistance contained in the said parameter with temperature. It is the performance estimation apparatus of the lead acid battery as described in any one of Claims 1 thru | or 5, Comprising:
The said internal resistance calculating part is a performance estimation apparatus of the lead acid battery which calculates the said internal resistance by setting the said internal resistance of the said lead acid battery to a function with a predetermined time constant. It is the performance estimation apparatus of the lead acid battery as described in any one of Claims 1 thru | or 6, Comprising:
The performance estimation apparatus of a lead storage battery further provided with the open circuit voltage correction | amendment part which correct | amends the said open circuit voltage with temperature. It is the performance estimation apparatus of the lead acid battery as described in any one of Claims 1 thru | or 7, Comprising:
Further comprising a health estimation unit that estimates the health of the lead-acid battery based on the parameters;
The said battery performance calculating part is a performance estimation apparatus of the lead storage battery which correct | amends the said open circuit voltage reduction | decrease using the said soundness degree. It is the performance estimation apparatus of the lead acid battery as described in any one of Claims 1 thru | or 8, Comprising:
The battery performance calculation unit calculates the soundness of the lead storage battery based on a comparison between the calculated current I and a predetermined reference value, or based on a comparison between the calculated time T and a predetermined reference value. The performance estimation apparatus of the lead acid battery which calculates the soundness degree of the said lead acid battery. Estimating the parameters and open circuit voltage of the lead storage battery based on the terminal voltage and charge / discharge current of the lead storage battery, respectively;
Calculating the internal resistance of the lead acid battery using the parameters;
The sum of the decrease in the open-circuit voltage of the lead-acid battery and the voltage drop in the internal resistance that occurs when the lead-acid battery is discharged for a time T with current I is equal to the difference between the open-circuit voltage and a predetermined discharge end voltage. And calculating the current I or the time T,
In the step of calculating the current I or the time T, when one of the current I and the time T is set to a predetermined value, the other of the current I and the time T is calculated. Performance estimation method.

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