JP2012141258A - Lead-acid battery state detection device and lead-acid battery state detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable accurate detection of the state of a lead-acid battery even when a jump-start is carried out.SOLUTION: A lead-acid battery state detection device 1 used for detecting a state of a lead-acid battery incorporated in a vehicle includes: current detection means (current sensor 12) for detecting a current flowing in a lead-acid battery 14; voltage detection means (voltage sensor 11) for detecting a voltage of the lead-acid battery; abnormal charging/discharging detection means (control part 10) for detecting an abnormal charging/discharging on the basis of a change in a current and a voltage detected by the current detection means and voltage detection means if an external device is directly connected to a terminal of the lead-acid battery and if the lead-acid battery is charged or discharged without going via the current detection means; and state detection means (control part 10) for detecting a state of the lead-acid battery by referring to a current value and a voltage value detected by the current detection means and voltage detection means and to a detection result of the abnormal charging detection means.

Description

  The present invention relates to a lead storage battery state detection device and a lead storage battery state detection method.

  In recent years, in automobiles and the like, the number of electric devices that operate with electric power stored in lead-acid batteries has increased, and devices related to driving safety such as electric steering and electric brakes are also driven by lead-acid batteries. It has come to be. For this reason, it is highly necessary to accurately know the state of charge (for example, SOC: State of Charge) of the lead storage battery.

  In general, when a lead-acid battery is in a stable state, there is a proportional relationship between the open circuit voltage (OCV) and the charge state, so the charge state is estimated by detecting the open end voltage. can do. However, in the case of a vehicle such as an automobile, power is supplied from the lead storage battery to each load when the engine is started, and power is supplied from the alternator to the lead storage battery, and charging and discharging repeatedly occur. The storage battery after charging / discharging is affected by the formation and annihilation reactions of ions on the electrode plate surface due to electrochemical reactions and the movement of ions due to electrolyte diffusion and convection. The proportional relationship of the state of charge will not be established.

  Patent Documents 1 and 2 disclose techniques for accurately estimating an open circuit voltage and a charged state even after charging and discharging.

JP 2009-2691 A JP 2009-300909 A

  By the way, in automobiles etc., the lead storage battery terminal of the faulty car and the terminal of the lead storage battery of the rescue car are directly connected by a cable as an emergency measure when the remaining capacity of the lead storage battery becomes insufficient and it becomes difficult to start the engine. Then, there is a case where a so-called “jump start” is performed in which the engine is started by receiving power supplied from the rescue vehicle.

  When such a jump start is executed, since the terminals are connected to each other, a current flows by bypassing the current sensor. For example, in the techniques described in Patent Documents 1 and 2, polarization and stratification are performed. The impact cannot be estimated accurately. For this reason, there exists a problem that the estimated open circuit voltage and charge condition will contain an error. In addition to jump start, for example, a charger may be directly connected to a lead-acid battery and the lead-acid battery may be charged. There is a problem of including.

  Therefore, the present invention provides a lead storage battery state detection device and a lead storage battery state detection method capable of accurately detecting the state of the lead storage battery even when irregular charging / discharging that bypasses the current sensor is performed. The purpose is to do.

In order to solve the above problems, the present invention provides a lead storage battery state detection device for detecting a state of a lead storage battery mounted on a vehicle, current detection means for detecting a current flowing through the lead storage battery, and a lead storage battery. A voltage detection means for detecting a voltage, and when the lead storage battery is charged or discharged without going through the current detection means when an external device is directly connected to the terminal of the lead storage battery, the current detection means and Non-regular charge / discharge detection means for detecting such irregular charge / discharge based on changes in current and voltage by the voltage detection means, and current values and voltage values detected by the current detection means and the voltage detection means And state detection means for detecting the state of the lead storage battery with reference to the detection result of the non-regular charge / discharge detection means.
According to such a configuration, the present invention can accurately detect the state of the lead-acid battery even when irregular charging / discharging that bypasses the current sensor is performed.

Further, in addition to the above invention, in another invention, the external device is a lead storage battery of another vehicle, and the non-regular charging / discharging is performed by connecting a lead storage battery of the other vehicle by a cable and performing jump start. Charging / discharging when executed, wherein the non-regular charging / discharging detecting means detects the charging / discharging when the jump start is executed.
According to such a configuration, the state of the lead storage battery can be accurately detected even when jump start is executed.

In addition to the above-mentioned invention, in the case where non-regular charge / discharge detection means detects non-regular charge / discharge, another invention takes into account the amount of change in polarization phenomenon caused by the non-normal charge / discharge. It is characterized by estimating the state of the lead storage battery.
According to such a configuration, the state of the lead storage battery can be accurately detected regardless of the change in the polarization phenomenon.

Further, in addition to the above-described invention, in the case where non-regular charge / discharge is detected by the non-regular charge / discharge detection means, the other invention takes into account the amount of change in stratification caused by the non-normal charge / discharge. It is characterized by estimating the state of the lead storage battery.
According to such a configuration, the state of the lead storage battery can be accurately detected regardless of the change in the stratification phenomenon.

According to another invention, in addition to the above-described invention, in the case where irregular charging / discharging is detected by the irregular charging / discharging detecting means, the state detecting means is configured to measure the lead measured during irregular charging / discharging. The impedance value of the storage battery is discarded.
According to such a configuration, it is possible to prevent erroneous detection of the state by discarding the impedance of the lead storage battery including an error.

In addition to the above-mentioned invention, in another invention, when non-regular charging / discharging is detected by the non-regular charging / discharging detecting means, the occurrence of irregular charging / discharging is notified to another device. It is characterized by.
According to such a configuration, it is possible to notify the other device that it is under a special situation by notifying the other device of the occurrence of irregular charging / discharging.

Further, the present invention provides a lead storage battery state detection method for detecting a state of a lead storage battery mounted on a vehicle with reference to detection results of a current detection means and a voltage detection means, with respect to a terminal of the lead storage battery. When the device is directly connected and the lead storage battery is charged or discharged without going through the current detection means, such irregularity is determined based on the current and voltage changes by the current detection means and the voltage detection means. A non-regular charge / discharge detection step for detecting the charge / discharge of the battery, the current value and the voltage value detected by the current detection means and the voltage detection means, and the detection result of the non-normal charge / discharge detection means And a state detecting step for detecting the state.
According to such a configuration, the present invention can accurately detect the state of the lead-acid battery even when irregular charging / discharging that bypasses the current sensor is performed.

  According to the present invention, the present invention provides a lead-acid battery state detection device and a lead-acid battery state capable of accurately detecting the state of the lead-acid battery even when irregular charging / discharging that bypasses the current sensor is performed. A detection method can be provided.

It is a figure which shows the structural example of the startability determination apparatus which concerns on embodiment of this invention. It is a block diagram which shows the detailed structural example of the control part of FIG. It is a figure which shows the change of the voltage of a lead storage battery by the influence of stratification and polarization. It is a figure which shows the relationship between stratification and charge polarization, and an actual capacity | capacitance. It is a figure which shows the change of the voltage during driving | running | working and a stop of a vehicle. It is a flowchart for demonstrating an example of the process which determines the presence or absence of a jump start. It is a figure for demonstrating the operation | movement principle of the flowchart shown in FIG. It is a figure for demonstrating the operation | movement principle of the flowchart shown in FIG. It is a flowchart for demonstrating an example of the process which calculates | requires a polarization correction coefficient and a stratification correction coefficient. It is a figure which shows the voltage change during driving | running | working and a rest. It is a flowchart for demonstrating an example of the process which discards a cranking resistance.

  Next, an embodiment of the present invention will be described.

(A) Description of Configuration of Embodiment FIG. 1 is a diagram illustrating a power supply system of a vehicle having a lead storage battery state detection device according to an embodiment of the present invention. In this figure, the lead storage battery state detection device 1 includes a control unit 10, a voltage sensor 11, a current sensor 12, a temperature sensor 13, and a discharge circuit 15 as main components, and detects the state of the lead storage battery 14. Here, the control unit 10 refers to the outputs from the voltage sensor 11, the current sensor 12, and the temperature sensor 13 to detect the state of the lead storage battery 14. The voltage sensor 11 detects the terminal voltage of the lead storage battery 14 and notifies the control unit 10. The current sensor 12 detects the current flowing through the lead storage battery 14 and notifies the control unit 10 of the current. The temperature sensor 13 detects the lead storage battery 14 itself or the ambient environmental temperature and notifies the control unit 10 of it. The discharge circuit 15 is configured by, for example, a semiconductor switch and a resistance element connected in series, and the lead-acid battery 14 is intermittently discharged when the control unit 10 performs on / off control of the semiconductor switch.

  The lead storage battery 14 is constituted by, for example, a so-called liquid lead storage battery using lead dioxide for the positive electrode (anode plate), spongy lead for the negative electrode (cathode plate), and dilute sulfuric acid as the electrolyte, and is charged by the alternator 16. The starter motor 18 is driven to start the engine, and power is supplied to the load 19. The alternator 16 is driven by the engine 17 to generate AC power, convert it into DC power by a rectifier circuit, and charge the lead storage battery 14.

  The engine 17 is composed of, for example, a reciprocating engine such as a gasoline engine and a diesel engine, a rotary engine, or the like. The engine 17 is started by a starter motor 18 and drives driving wheels via a transmission to give propulsive force to the vehicle. Drive to generate power. The starter motor 18 is constituted by, for example, a DC motor, and generates a rotational force by the electric power supplied from the lead storage battery 14 to start the engine 17. The load 19 is configured by, for example, an electric steering motor, a defogger, an ignition coil, a car audio, a car navigation, and the like, and operates with electric power from the lead storage battery 14.

  FIG. 2 is a diagram illustrating a detailed configuration example of the control unit 10 illustrated in FIG. 1. As shown in this figure, the control unit 10 includes a CPU (Central Processing Unit) 10a, a ROM (Read Only Memory) 10b, a RAM (Random Access Memory) 10c, a communication unit 10d, a display unit 10e, and an I / F (Interface). 10f. Here, the CPU 10a controls each unit based on the program 10ba stored in the ROM 10b. The ROM 10b is configured by a semiconductor memory or the like, and stores a program 10ba or the like. The RAM 10c is configured by a semiconductor memory or the like, and stores a parameter 10ca generated when the program 10ba is executed. The communication unit 10d is connected to another device (for example, an ECU (Engine Control Unit) (not shown)) via a communication line, and exchanges information with another device. The display unit 10e is configured by, for example, a liquid crystal display that displays information supplied from the CPU 10a. The I / F 10 f converts the signals supplied from the voltage sensor 11, the current sensor 12, and the temperature sensor 13 into digital signals and takes them in, and supplies a driving current to the discharge circuit 15 to control it.

(B) Description of outline of operation | movement of embodiment Next, with reference to FIGS. 3-5, the outline | summary of operation | movement of embodiment is demonstrated. Hereinafter, after describing the polarization phenomenon and the stratification phenomenon of the liquid lead-acid battery, an outline of the operation of the present embodiment will be described. First, the polarization phenomenon will be described. The polarization phenomenon includes charge polarization that occurs during charging and discharge polarization that occurs during discharge. Here, the charge polarization phenomenon refers to a phenomenon in which the ion density on the electrode surface increases due to a delay in the electrochemical reaction on the electrode surface of the lead storage battery 14 during charging, and the output voltage of the lead storage battery 14 increases. The discharge polarization phenomenon is a phenomenon in which the ion density is reduced on the electrode surface during discharge, and the output voltage of the lead storage battery 14 is lowered.

  On the other hand, the stratification phenomenon refers to a phenomenon in which an output voltage changes due to a difference in specific gravity between an upper part and a lower part of an electrolyte during discharging or charging. Specifically, in a liquid lead-acid battery, the upper part of the vertical direction of the electrode is preferentially discharged at the beginning of discharge, so that the specific gravity of the upper part of the electrolyte is lower than that of the lower part. Next, in charging, lead sulfate generated by discharge changes to metallic lead and sulfuric acid, so that high-concentration sulfuric acid is released into the electrolytic solution. Therefore, the released sulfuric acid settles toward the lower part, and stratification occurs where a specific gravity difference occurs between the upper part and the lower part of the electrolytic solution.

  FIG. 3 shows the relationship between the polarization phenomenon and the stratification phenomenon and the voltage. As shown in FIG. 3, the stratification phenomenon and the charge polarization phenomenon affect the direction in which the voltage of the lead storage battery 14 becomes higher than the open circuit voltage, and the influence decreases with time. Further, the discharge polarization phenomenon affects the direction in which the voltage of the lead storage battery 14 becomes lower than the open circuit voltage, and the influence decreases with time.

  FIG. 4 is a diagram showing the relationship between the open circuit voltage, stratification, and charge polarization. As shown on the left side of FIG. 4, the voltage measured as the apparent voltage of the lead storage battery 14 includes an increase in voltage due to stratification and charge polarization. As described above, the increase in voltage due to stratification and charge polarization decreases with the passage of time, so after a predetermined time has elapsed, as shown on the right side of FIG. 4, compared to the left side of FIG. The part of stratification and charge polarization is reduced.

  FIG. 5 shows voltage changes while the lead storage battery 14 is running and the vehicle is at rest. In FIG. 5, the voltage of the lead storage battery 14 is maintained at about 14 V during traveling, but the voltage decreases with time and approaches the open circuit voltage while the vehicle is at rest.

  Here, the voltage change due to stratification and polarization is merely an apparent voltage increase, and is independent of the dischargeable capacity of the lead storage battery 14. Therefore, when the open circuit voltage and the charge rate of the lead storage battery 14 are determined based on the apparent voltage including the stratification and the charge polarization, a value larger than the actual open circuit voltage or the charge rate is obtained. Therefore, in order to eliminate the influence of stratification and polarization and to obtain an accurate open-circuit voltage and charging rate, the polarization amount and the stratification amount were estimated from the integrated value of the charge / discharge current flowing in the lead storage battery 14 and estimated. Conventionally, an open circuit voltage indicating the actual capacity in FIG. 4 is obtained based on the polarization amount and the stratification amount. For example, a specific method is described in Patent Document 2 and the like.

  By the way, when the lead storage battery 14 rises (when the charge amount decreases and the engine cannot be started), the lead storage battery 14 of another vehicle and the lead storage battery 14 of the failed vehicle are directly connected by a connection cable. There is a case where a so-called “jump start” is performed in which the engine 17 is started by receiving power supply from the lead storage battery of the vehicle. In such a jump start, since the terminals of the lead storage battery are directly connected by a cable, the current flowing between the two lead storage batteries is not detected by the current sensor 12. For this reason, since an error occurs in the integrated value of the charge / discharge current flowing in the lead storage battery 14 described above, the estimated values of the polarization amount and the stratification amount include errors. As a result, a value higher than the actual open-circuit voltage or the charging rate is estimated, and if the lead storage battery 14 is used with the assumption that there is a margin in the charge amount, the battery may run out or the engine 17 cannot be restarted. It may become.

  Therefore, in this embodiment, whether or not jump start is executed is detected from changes in current and voltage flowing in the lead storage battery 14 as described later. Then, when a jump start is detected, a jump start occurrence flag is set to jump to another device (for example, an ECU (not shown)) connected to the communication unit 10d of the lead storage battery state detection device 1. Notify that a start has occurred. Further, the value of the correction coefficient for eliminating the influence of stratification and polarization is adjusted based on the open circuit voltage OCV1 obtained from the current integration and the OCV2 obtained from the voltage transition. Furthermore, the internal resistance of the lead storage battery 14 obtained at the time of jump start is discarded because it is not accurate because current is exchanged with other lead storage batteries. By such processing, when a jump start is executed, the occurrence of the jump start is notified to other devices, for example, by operating in an operation mode different from normal (suppressing power consumption), Power consumption can be reduced. Further, the actual capacity can be accurately known by adjusting the value of the correction coefficient for eliminating the effects of stratification and polarization. Further, by discarding the internal resistance of the lead storage battery 14, it is possible to prevent an erroneous determination based on an inaccurate parameter.

(C) Description of Detailed Operation of Embodiment Next, the detailed operation of this embodiment will be described with reference to FIGS. FIG. 6 is a flowchart for explaining the flow of processing executed in the control unit 10 shown in FIG. 2 in order to detect that irregular charging / discharging such as jump start has been executed. Note that the processing shown in FIG. 6 is executed, for example, in a cycle of 10 ms during traveling of a vehicle in which fluctuations in current and voltage are severe, and is executed, for example, in a cycle of 1 s when these fluctuations are gentle. . When the processing of the flowchart shown in FIG. 6 is started, the following steps are executed.

  In step S1, the CPU 10a refers to the output of the current sensor 12, and acquires the current value I1 at that time.

  In step S2, the CPU 10a acquires the current value I2 obtained by the previous process (stored in the RAM 10c by the process of step S9 described later) from the parameter 10ca of the RAM 10c, and the current value I1 acquired in step S1 is the same as the current value I1 acquired in step S1. The difference ΔI (= I1−I2) is calculated.

  In step S3, the CPU 10a refers to the output of the voltage sensor 11 and acquires the voltage value V1 at that time.

  In step S4, the CPU 10a acquires the voltage value V2 obtained by the previous process from the parameter 10ca of the RAM 10c, and calculates a difference ΔV (= V1−V2) from the voltage value V1 acquired in step S3.

  In step S5, the CPU 10a acquires the static impedance Z that is measured while the vehicle is stopped and stored as the parameter 10ca in the RAM 10c. Here, the static impedance Z refers to the internal impedance of the lead storage battery 14 measured in a state where the lead storage battery 14 is electrically balanced. This static impedance is measured from changes in current and voltage at the time when pulse discharge is performed at a predetermined cycle by the discharge circuit 15 while the vehicle is stopped. The cranking resistance described later is a resistance obtained from a current and a voltage detected when the engine 17 is started by the starter motor 18 (when a large current flows). This is referred to as static impedance.

  In step S6, the CPU 10a calculates D based on the following equation (1).

  D = ΔV−Z × ΔI (1)

  Here, since Ohm's law is established among the voltage V, the current I, and the impedance Z of the lead storage battery 14, ΔV = Z × ΔI (ΔV−Z × ΔI = 0) is established in the normal state. . However, when the jump start is executed, the voltage rises due to the supply of current from the rescue vehicle even though the current I is not detected on the failed vehicle side. As a result, on the broken vehicle side, the value of D becomes a positive value as shown in FIG. In the example of FIG. 7, the horizontal axis indicates time, the vertical axis indicates voltage and current, jump start is executed in the center of the figure (lead-acid batteries are connected by a cable), and temporarily ΔV−Z × ΔI> 0. On the other hand, although the current I is not detected on the rescue vehicle side, current is supplied to the failed vehicle side, so the voltage drops. As a result, on the rescue vehicle side, the value of D becomes a negative value as shown in FIG. In the example of FIG. 8, a jump start is executed in the center of the figure (lead-acid batteries are connected by a cable), and at that time, ΔV−Z × ΔI <0 is temporarily satisfied.

  In step S7, the CPU 10a determines whether or not the absolute value | D | of D obtained in step S6 is larger than the threshold Th, and if | D |> Th is satisfied (step S7: Yes), the step The process proceeds to S8, and otherwise (step S7: No), the process proceeds to step S9. Here, the threshold value Th may be a value that can detect a change in ΔV−Z × ΔI shown in FIGS. 7 and 8 and that is not affected by noise based on voltage and current fluctuations.

  In step S8, the CPU 10a sets a jump start occurrence flag indicating “jump start” to “1”. The jump start occurrence flag can also be referred to from other devices (for example, the load 19 and ECU (not shown)) connected to the communication unit 10d of the lead storage battery state detection device 1 shown in FIG. For example, the device can be operated in an operation mode different from normal (suppressing power consumption) to reduce power consumption.

  In step S9, the CPU 10a substitutes the current I1 and voltage V1 detected in steps S1 and S3 for variables I2 and V2 that hold the previous values, respectively. As a result, these values are stored in the parameter 10ca of the RAM 10c and used as I2 and V2 in the next processing.

  According to the above process, it is possible to detect the occurrence of a jump start on both the broken vehicle side and the rescue vehicle side.

  Next, with reference to FIG. 9, a process for adjusting the value of the correction coefficient for excluding the effects of stratification and polarization will be described. The process of FIG. 9 is a process executed at a predetermined cycle, for example. When the processing of this flowchart is started, the following steps are executed.

  In step S20, the CPU 10a determines whether or not the jump start occurrence flag is “1”. If it is “1” (step S20: Yes), the process proceeds to step S21, and otherwise (step S20). : No), the process ends. For example, if a jump start is executed at time t2 shown in FIG. 10, the jump flag is set to “1” in the process of step S8 of FIG. 6, so that the determination in step S20 is Yes and step S21. Proceed to

  In step S21, the CPU 10a obtains the open circuit voltage OCV2 from the voltage transition. Specifically, as shown in FIG. 5, when the engine 17 is stopped, the voltage of the lead storage battery 14 gradually decreases with time and approaches the open circuit voltage. At this time, it is known that there is a certain correlation between the voltage change rate m at a certain point in time and the voltage dV that is the difference between the open circuit voltage. Therefore, a table or a mathematical expression in which such correlation is quantified is stored in the RAM 10c, and the voltage or the like is calculated by referring to the table based on the voltage V and the change rate m of the lead storage battery 14 at a certain time. OCV2 can be determined. In the example of FIG. 10, OCV2 after the engine 17 is stopped at time t3 changes as indicated by a broken line.

  In step S22, the CPU 10a obtains the final update value of the open circuit voltage OCV1 obtained by current integration and stored as the parameter 10ca in the RAM 10c. Here, the current integration is a method in which the current value discharged or charged from the lead storage battery 14 is constantly measured, and the measured current value is integrated to obtain the charge rate of the lead storage battery 14. Since there is a substantially linear relationship between the open circuit voltage OCV1 and the charge rate SOC1, the open circuit voltage OCV1 can be obtained from the charge rate SOC1 based on such a relationship. The calculation of the open circuit voltage OCV1 and the charging rate SOC1 based on the current integration is executed at predetermined time intervals, and the obtained open circuit voltage OCV1 and the charging rate SOC1 are overwritten and stored in the RAM 10c as a parameter 10ca. In the example of FIG. 10, the last stored open circuit voltage OCV1 is acquired when the engine 17 is stopped at time t3.

  In step S23, the CPU 10a applies the difference (OCV1−OCV2) between the open circuit voltage OCV1 and the open circuit voltage OCV2 to the function f1 () for determining the polarization correction coefficient C1r, and determines the polarization correction coefficient C1r. Here, the polarization correction coefficient C1r is a coefficient for correcting the polarization amount C1 that the control unit 10 has as an estimated value in order to exclude an error due to polarization according to the detection of the jump start. Specifically, when a jump start is detected, for example, C1 ← C1-C1r (← indicates substitution of a value into a variable), and the polarization amount C1 is corrected.

  The open circuit voltage OCV1 is obtained by current integration. For this reason, when the jump start is executed, the current flowing between the other lead storage batteries cannot be detected by the current sensor 12, and therefore the current flowing at this time is not reflected in the open circuit voltage OCV1. On the other hand, the open circuit voltage OCV2 is obtained by a method (details will be described later) different from the current integration. In this method, the OCV2 is measured in a state including the current flowing between the lead acid batteries. For this reason, the value of these differences (OCV1-OCV2) becomes larger when jump start is executed than when it is not executed. Therefore, as an example of a method for realizing the function f1 (), for example, a table in which the value of (OCV1-OCV2) and the polarization correction coefficient C1r are associated is prepared in the RAM 10c in advance, and the difference value described above in the table is prepared. Is applied, the polarization correction coefficient C1r can be obtained.

  In step S24, the CPU 10a applies the difference (OCV1-OCV2) between the open circuit voltage OCV1 and the open circuit voltage OCV2 to the function f2 () for determining the stratification correction coefficient C2r, and obtains the stratification correction coefficient C2r. Here, the stratification correction coefficient C2r is a coefficient for correcting the stratification amount C2 that the control unit 10 has as an estimated value in order to exclude an error due to stratification according to the detection of the jump start. is there. Specifically, when a jump start is detected, for example, C2 ← C2-C2r is set, and the stratification amount C2 is corrected. The relationship between the open-circuit voltage OCV1 and the open-circuit voltage OCV2 is the same as that described above, and a table showing the correspondence relationship between the stratification correction coefficient C2r and (OCV1-OCV2) is prepared in the RAM 10c in advance, and The stratification correction coefficient C2r can be obtained by making the determination based on the same as in the case described above.

  Through the above processing, the polarization correction coefficient C1r and the stratification correction coefficient C2r are obtained. By using such a correction coefficient, even when the stratification and polarization change due to jump start, the stratification quantity after change and the stratification quantity and polarization before correction are corrected by these correction coefficients. The amount of polarization can be obtained.

  Next, a process of discarding the cranking resistor R will be described with reference to FIG. The process of the flowchart shown in FIG. 11 is executed at regular time intervals, for example. When the processing of FIG. 11 is started, the following steps are executed.

  In step S40, the CPU 10a determines whether or not the jump start occurrence flag is “1”. If it is “1” (step S40: Yes), the process proceeds to step S41, and otherwise (step S40). : No), the process ends.

  In step S41, the CPU 10a discards the cranking resistance R measured in cranking at the time of jump start (rotating and driving the engine 17 by the starter motor 18) and stored in the RAM 10c as the parameter 10ca. Here, the cranking resistor R is a real component of the impedance obtained from the current flowing from the lead storage battery 14 to the starter motor 18 and the terminal voltage of the lead storage battery 14 when the engine 17 is rotationally driven by the starter motor 18. . That is, in the cranking at the jump start, since current is exchanged with the lead storage battery of another vehicle, the cranking resistance R cannot be accurately obtained. Therefore, such a cranking resistance R is discarded. For this reason, it is possible to prevent an erroneous determination based on the cranking resistance including an error.

(D) Description of Modified Embodiment The above embodiment is an example, and it is needless to say that the present invention is not limited to the case described above. For example, in the above embodiment, the case where the jump start is executed has been described as an example. However, the “non-regular charge / discharge” in the present application is not limited to this, for example, commercial power supply power. If the battery is charged by a charger that charges the lead storage battery by converting the power to DC power, or if an external device (for example, an inverter that converts DC power to AC power) is connected to the lead storage battery You may make it detect as regular charging / discharging.

  Moreover, in the above embodiment, the jump start which is non-regular charge / discharge is detected based on the formula (1), but other formulas may be used. For example, you may make it determine based on the following formula | equation (2) using not the impedance but the conductance G.

D = ΔI−G × ΔV (2)

  Alternatively, instead of the static impedance Z, a constant K may be used, and when the difference between ΔI × K and ΔV changes, it may be determined that the irregular charging / discharging has been executed.

  Further, although the polarization amount and the stratification amount are corrected based on the equations shown in step S23 and step S24, they may be corrected based on other equations. Further, the polarization amount and the stratification amount are individually corrected. However, these may be collectively set as one amount, and may be corrected collectively.

  Further, in the above embodiment, in order to detect both the broken vehicle and the rescue vehicle, the occurrence of a jump start is determined by comparing the absolute value of D with the threshold value Th by the process of step S7 in FIG. did. Here, since the amount of polarization and the amount of stratification are reduced on the rescue vehicle side due to the jump start, the influence of the amount of polarization and the amount of stratification is small compared to the failure vehicle side. However, on the rescue vehicle side, since the current is taken out by jump start, the actual charging rate is lower than the charging rate detected by the sensor. In this case, if the lead storage battery 14 is used based on the detected charging rate, the lead storage battery 14 may be lifted. Thus, for example, after the jump start occurrence flag is set to “1” in the process of step S8 in FIG. 6, when D is positive, the processes of FIGS. 9 and 11 are executed. When D is negative, for example, 9 is not executed, only the process of FIG. 11 is executed to notify that the charging rate is lower than the detected charging rate, and the charging rate is recalculated as necessary. Good. That is, you may make it distinguish the process performed in each of a failure vehicle and a rescue vehicle. Needless to say, when D is negative, not only the process of FIG. 11 but also the process of FIG. 9 may be executed as necessary.

DESCRIPTION OF SYMBOLS 1 Lead storage battery state detection apparatus 10 Control part (non-regular charge / discharge detection means, state detection means)
10a CPU
10b ROM
10c RAM
10d Communication unit 10e Display unit 10f I / F
11 Voltage sensor (voltage detection means)
12 Current sensor (current detection means)
DESCRIPTION OF SYMBOLS 13 Temperature sensor 14 Lead acid battery 15 Discharge circuit 16 Alternator 17 Engine 18 Starter motor 19 Load

Claims (7)

In the lead storage battery state detection device that detects the state of the lead storage battery mounted on the vehicle,
Current detecting means for detecting a current flowing in the lead acid battery;
Voltage detecting means for detecting the voltage of the lead storage battery;
When an external device is directly connected to the terminal of the lead storage battery and the lead storage battery is charged or discharged without going through the current detection means, the current and voltage of the current detection means and the voltage detection means are Non-regular charge / discharge detection means for detecting such irregular charge / discharge based on the change,
State detection means for detecting the state of the lead storage battery with reference to the current value and the voltage value detected by the current detection means and the voltage detection means and the detection result of the irregular charge / discharge detection means;
A lead-acid battery state detection device comprising: The external device is a lead storage battery of another vehicle,
The irregular charging / discharging is charging / discharging when the lead storage battery of the other vehicle is connected by a cable and jump start is executed,
The non-regular charge / discharge detection means detects the charge / discharge at the time of the jump start execution.
The lead-acid battery state detection device according to claim 1.   When the non-regular charge / discharge detection means detects non-normal charge / discharge, the state of the lead storage battery is estimated in consideration of the amount of change in the polarization phenomenon caused by the non-normal charge / discharge. Item 3. The lead-acid battery state detection device according to item 1 or 2.   When the irregular charging / discharging detection means detects irregular charging / discharging, the state of the lead storage battery is estimated in consideration of the amount of change in the stratification phenomenon caused by the irregular charging / discharging. Item 4. The lead-acid battery state detection device according to any one of Items 1 to 3.   The non-regular charge / discharge detection unit detects the non-normal charge / discharge, and the state detection unit discards the impedance value of the lead storage battery measured during the non-normal charge / discharge. Item 5. The lead-acid battery state detection device according to any one of Items 1 to 4.   6. The apparatus according to claim 1, wherein when the non-regular charge / discharge detection unit detects non-normal charge / discharge, the other apparatus is notified of the occurrence of the non-normal charge / discharge. Lead-acid battery state detection device as described in the item. In the lead storage battery state detection method for detecting the state of the lead storage battery mounted on the vehicle with reference to the detection results of the current detection means and the voltage detection means,
When an external device is directly connected to the terminal of the lead storage battery and the lead storage battery is charged or discharged without going through the current detection means, the current and voltage of the current detection means and the voltage detection means are A non-regular charge / discharge detection step for detecting such irregular charge / discharge based on the change;
A state detection step of detecting the state of the lead-acid battery with reference to the current value and voltage value detected by the current detection means and the voltage detection means and the detection result of the non-regular charge / discharge detection means;
A lead-acid battery state detection method comprising:

Images