JP2019078571A - Power supply system - Google Patents

Abstract

To provide a power supply system with which it is possible to determine with high accuracy degradation of a lead battery used for supplying electric power to an electric load of a vehicle.SOLUTION: A power supply system comprises a lead battery for supplying electric power to an electric load of a vehicle, a battery sensor unit for acquiring a value pertaining to a state of this lead battery, and an ECU for determining degradation of the lead battery on the basis of the value acquired by the battery sensor unit. The battery sensor unit acquires a temperature value of the lead battery during travelable time from when an ignition switch is turned on to when it is turned off and during soak time from when the ignition switch is turned off to when it is turned on, and the ECU determines the degradation of the lead battery due to corrosion of a positive electrode grid on the basis of the temperature value acquired by the battery sensor unit.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a power supply system. More particularly, the present invention relates to a power supply system including a lead battery for supplying power to an electric load of a vehicle.

  The vehicle is equipped with a lead battery to provide power to vehicle accessories such as air conditioners, lights, and navigation systems. In addition, a generator is mounted on the vehicle, and for example, it is possible to drive the generator using the power of the engine and charge the lead battery appropriately.

  Although the lead battery degrades according to the use mode, in order to control the charge and discharge of the lead battery efficiently, it is necessary to appropriately determine the degree of degradation. Patent Document 1 discloses an apparatus for determining the deterioration of a lead battery. Since the internal resistance of a lead battery tends to increase with the progress of deterioration, the device of Patent Document 1 calculates its internal resistance based on the current and voltage of the lead battery, and based on this internal resistance. Determine the deterioration.

JP, 2016-109639, A

  However, the degree of deterioration of the lead battery can not be identified with high accuracy only by the internal resistance. In addition, the lead battery is deteriorated by various factors, and the specific content of the measures to be taken to extend the life of the lead battery depends on the deterioration factor, but the deterioration factor can not be identified by the internal resistance alone . For this reason, it has been required to determine the deterioration of the lead battery by a parameter different from the internal resistance.

  An object of the present invention is to provide a power supply system capable of accurately determining the deterioration of a lead battery used to supply power to an electric load of a vehicle.

  (1) The power supply system (for example, power supply system S described later) of the present invention supplies electric power to the electric load (for example, first electric load 51 and second electric load 52 described later) of a vehicle (for example, vehicle V described later) And a battery state acquisition device (for example, a battery sensor unit 6 described later) for acquiring a value related to the state of the lead battery, and a battery state acquisition device for acquiring the value. A battery deterioration determination device (for example, an ECU 7 described later) that determines the deterioration of the lead battery based on a value; the battery state acquisition device acquires the value of the temperature of the lead battery; The apparatus is characterized in that the deterioration of the lead battery is determined based on a temperature acquisition value by the battery state acquisition apparatus.

  (2) In this case, the battery state acquisition device can travel when the vehicle is in the travel enable state until it can not travel and when the vehicle is in the travel impossible state after the vehicle is in the travel impossible state. Obtaining the value of the temperature of the lead battery at the time of soaking, and the battery deterioration determining device determining the deterioration of the lead battery based on the temperature acquisition value at the time of traveling and the temperature acquisition value at the time of the soak Is preferred.

  (3) In this case, the battery deterioration determining device is an association unit that associates the temperature of the lead battery with an increase per unit time of a deterioration parameter (for example, a corrosion amount described later) indicating the progress of deterioration of the lead battery. Calculating the value of the deterioration parameter (for example, a corrosion amount estimated value described later) by integrating the increase per unit time obtained by inputting the temperature acquisition value by the battery state acquisition device to the association means. It is preferable to determine the deterioration of the lead battery based on the value of the deterioration parameter.

  (4) In this case, it is preferable that the association unit increases the increase as the temperature acquisition value by the battery state acquisition device increases.

  (5) In this case, the power supply system includes a generator (for example, ACG 21 described later) connected to the lead battery, and a generator control device (for example, ECU 7 described later) for controlling the generated voltage of the generator. And the generator control device determines that the battery deterioration determination device determines that the lead battery has deteriorated, the charging current flowing from the generator to the lead battery and the electric load from the lead battery It is preferable to control the generated voltage such that both or any of the discharge currents flowing to the battery is smaller than before it is determined that the lead battery has deteriorated.

  (6) In this case, it is preferable that the deterioration parameter is a parameter indicating the progress of deterioration due to the corrosion of the electrode of the lead battery.

  (1) One of the causes of lead battery deterioration is the progress of corrosion of the positive electrode grid. That is, when the corrosion of the positive electrode grid progresses, the conduction path in the lead battery is broken, and the internal resistance increases. As will be described later with reference to FIG. 3, the corrosion of the positive electrode grid of the lead battery starts to progress from the time of manufacture (more specifically, the time of manufacture or when charging / discharging is started after mounting on a vehicle). Also, the rate of progression of corrosion is correlated with the temperature of the lead battery. Therefore, in the power supply system of the present invention, the battery state acquisition device acquires the value of the temperature of the lead battery, and the battery deterioration determining device determines the deterioration of the lead battery based on the temperature acquisition value. Therefore, according to the power supply system of the present invention, it is possible to determine the deterioration of the lead battery with a high degree of accuracy based on the cause specifically for the corrosion of the positive electrode grid.

  (2) The corrosion of the positive electrode grid proceeds not only at the time of traveling when the charge and discharge of the lead battery are actively performed but also at the time of soak when the charge and discharge of the lead battery is not actively performed. Further, the rate of progress of the corrosion of the positive electrode grid is correlated with the temperature as described above, and the degree of the progress of corrosion also changes depending on the temperature of the environment in which the lead battery is left at the time of soaking. Therefore, in the power supply system of the present invention, the battery state acquisition device acquires the temperature value of the lead battery not only when traveling but also during soaking, and the battery deterioration determination device acquires the temperature acquisition value and soak during traveling. The deterioration of the lead battery is determined based on the temperature acquisition value in Thus, the deterioration of the lead battery can be determined more accurately.

  (3) In the power supply system of the present invention, the battery deterioration determination device inputs the temperature acquisition value by the battery state acquisition device into the relating means that associates the temperature of the lead battery with the increase per unit time of the deterioration parameter. The amount of increase per unit time of the deterioration parameter is calculated, and the amount of increase is integrated to calculate the value of the deterioration parameter, and the deterioration of the lead battery is determined based on the value of the deterioration parameter. The rate of progress of the corrosion of the positive electrode grid of the lead battery is correlated with the temperature of the lead battery. In the present invention, the amount of increase is calculated for each unit time, and the value of the deterioration parameter is calculated by integrating this. Thus, the deterioration of the lead battery can be determined more accurately.

  (4) As will be described later with reference to FIG. 3, the rate of progress of corrosion of the positive electrode grid of the lead battery tends to be faster as the temperature of the lead battery is higher. In the power supply system of the present invention, in consideration of this characteristic, the increase in the deterioration parameter per unit time is increased as the temperature acquisition value by the battery state acquisition device increases. Thereby, the degree of deterioration due to the deterioration of the lead battery, in particular, the corrosion of the positive electrode grid can be appropriately represented by the deterioration parameter.

  (5) In the power supply system of the present invention, when the battery deterioration determination device determines that the lead battery has deteriorated, either or both of the charging current to the lead battery and the discharge current from the lead battery are deteriorated. The generated voltage by the generator is controlled to be smaller than before it is determined. As described above, since the rate of progress of deterioration due to corrosion of the positive electrode grid of the lead battery tends to be higher as the temperature is higher, the lead battery may be reduced by reducing the charge current and / or the discharge current. Since the heat generation can be suppressed, it is possible to delay the progress of the deterioration due to the corrosion of the positive electrode grid of the lead battery and to prolong the life of the lead battery.

  (6) In the power supply system of the present invention, the deterioration parameter is a parameter indicating the progress of deterioration due to the corrosion of the lead battery electrode. Thereby, the degree of deterioration due to the deterioration of the lead battery, in particular, the corrosion of the positive electrode grid can be appropriately represented by the deterioration parameter.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the power supply system which concerns on one Embodiment of this invention, and the vehicle carrying this power supply system. It is a figure which shows typically the factor of deterioration of a battery. It is a figure which shows the result of the test done in order to identify the factor which advances deterioration of positive electrode grid | lattice corrosion. It is a flowchart which shows the specific procedure which determines deterioration of the battery resulting from positive electrode lattice corrosion. It is a figure which shows an example of a corrosion amount increase rate calculation table. It is a figure for demonstrating the specific procedure of the deterioration suppression action for suppressing the deterioration resulting from positive electrode grid | lattice corrosion. It is a figure which shows the result of the test done in order to identify the factor which advances sulfation degradation. It is a figure which shows the result of the test done in order to identify the factor which advances sulfation degradation. It is a flowchart which shows the specific procedure which determines deterioration of the battery resulting from sulfation deterioration. It is a figure which shows an example of a sulfation deterioration degree increase rate calculation table. It is a figure for demonstrating the specific procedure of the deterioration suppression action for suppressing the deterioration resulting from a sulfation deterioration. It is a figure for demonstrating the specific procedure of the deterioration suppression action for suppressing the deterioration resulting from a sulfation deterioration. It is a figure which shows the result of the test done in order to specify the factor which accelerates | stimulates softening of a positive electrode active material. It is a figure for demonstrating the procedure which calculates the value of effective charging / discharging amount. It is a figure which shows an example of a degradation acceleration coefficient calculation map. It is a figure which shows an example of a degradation acceleration coefficient calculation map. It is a figure which shows an example of a degradation acceleration coefficient calculation map. It is a figure for demonstrating the concrete procedure of the deterioration suppression action using an effective charging / discharging amount.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a view showing a configuration of a power supply system S according to the present embodiment and a vehicle V on which the power supply system S is mounted. The vehicle V includes an internal combustion engine 1 (hereinafter referred to as "engine 1") as a power generation source for rotating drive wheels (not shown).

  The power supply system S includes a battery 3 connected to loads mounted on the vehicle V such as the first electric load 51 and the second electric load 52 and supplying power to the loads 51 and 52, and a battery 3 for the loads 51 and 52. And an alternator 21 (hereinafter abbreviated as “ACG 21”) connected in parallel to generate electricity using the power of the engine 1, and a starter 23 for starting the engine 1 using power supplied from the battery 3 , DCDC converter 53 for boosting or lowering DC power of battery 3 or ACG 21 and supplying it to the second electric load 52, battery sensor unit 6 for acquiring values of various parameters for specifying the state of battery 3, engine 1, the ECU 7 which is an electronic control module that controls the ACG 21, the starter 23, the battery 3 and the like, and the driver starts the vehicle V Comprises, an ignition switch 9 which is operated to stop.

  The electric loads 51 and 52 are configured by various electronic devices mounted on the vehicle V, such as lights, air conditioners, navigation systems, electric power steering, and audio devices.

  The ACG 21 is connected to a crankshaft of the engine 1 via a belt (not shown), and is a generator that generates electric power by being rotationally driven by the crankshaft. The electric power generated by the ACG 21 is supplied to the first electric load 51, the second electric load 52, and the DC-DC converter 53, consumed by these electric loads, and also consumed to charge the battery 3.

  The ACG 21 is configured by a regulator, a rotor coil, and the like. The ECU 7 as a generator control device for controlling the ACG 2 adjusts the current flowing through the rotor coil by controlling the switch of the regulator on / off, and controls the voltage generated by the ACG 21. While the vehicle V is traveling, the ECU 7 represents the charging rate of the battery 3 (the percentage of the remaining capacity of the battery 3 to the full charging capacity, which is estimated by the battery sensor unit 6 described later). (Also referred to as “state of charge)” controls the generated voltage of the ACG 21 such that the target SOC set in the ECU 7 is maintained.

  More specifically, the ECU 7 controls the generated voltage of the ACG 21 to be higher than the output voltage of the battery 3 when, for example, the SOC of the battery 3 is lower than the target SOC and charging of the battery 3 is required. , Charging the battery 3 and supplying necessary power to the electric loads 51 and 52. Further, for example, when the SOC of the battery 3 is higher than the target SOC and the discharge of the battery 3 is required, the ECU 7 controls the generated voltage of the ACG 21 to be lower than the output voltage of the battery 3 to obtain electricity from the battery 3 Promote discharge to the loads 51 and 52. As described above, the ECU 7 controls the charge amount and the discharge amount of the battery 3 by controlling the generated voltage of the ACG 21 to maintain the SOC of the battery 3 at approximately the target SOC.

  Further, when an operation request for a specific electric load (specifically, for example, an air conditioner) having a large power consumption among the electric loads included in the electric loads 51 and 52 is generated, the ECU 7 responds to the operation request to meet the operation request. Is increased to a predetermined set voltage higher than the output voltage of the battery 3 to supply necessary power from the ACG 21 to the specific electric load. Therefore, the battery 3 may be forcibly charged when the specific electrical load is activated.

  The battery 3 is a secondary battery capable of both discharging that converts chemical energy into electrical energy and charging that converts electrical energy into chemical energy. The battery 3 is a so-called lead storage battery using lead dioxide for the positive electrode, cancellous lead for the negative electrode, and dilute sulfuric acid as the electrolyte. More specifically, for example, as the positive electrode, one in which lead dioxide is applied as an active material to an electrode grid made of lead or lead alloy is used. For example, for the negative electrode, one in which lead is applied as an active material to an electrode grid made of lead or lead alloy is used.

  The battery sensor unit 6 processes a plurality of sensors 61, 62, 63 that directly detect the state of the battery 3 and output signals of the sensors 61 to 63 to identify the state of the battery 3 And a battery parameter calculator 65 for calculating the value of the battery parameter.

  The battery current sensor 61 transmits a detection signal corresponding to the current flowing through the battery 3 to the battery parameter calculation unit 65. The battery voltage sensor 62 transmits a detection signal corresponding to the voltage between the positive and negative terminals of the battery 3 to the battery parameter calculation unit 65. The battery temperature sensor 63 transmits a detection signal corresponding to the temperature of the battery 3 to the battery parameter calculation unit 65.

  Battery parameter operation unit 65 uses the detection signals from sensors 61 to 63 to perform SOC [%], charge amount [Ah], discharge amount [Ah], discharge depth [%], and the like of battery 3 according to the following procedure. The values of SOH [%] indicating the degree of deterioration of the battery 3, average temperature [° C.], maximum temperature [° C.], and minimum temperature [° C.] are calculated, and these values are transmitted to the ECU 7.

  The value of the charge amount of the battery 3 is set to a charge current flowing into the battery 3 detected by the battery current sensor 61 for a predetermined period (for example, after the ignition switch 9 is turned on and then turned off) Calculated over the entire driving cycle). Further, the value of the discharge amount of the battery 3 is a discharge current flowing out of the battery 3 detected by the battery current sensor 61 in a predetermined period (for example, the driving cycle or the ignition switch 9 is turned off It is calculated by integrating over the soak period from when it is turned on.

  While the vehicle V is traveling (that is, in a period other than the above-described soak period), the battery parameter calculation unit 65 obtains a detection signal from the battery temperature sensor 63 at predetermined intervals, and performs averaging processing on the detection signal. The value of the average temperature of the battery 3 for each period (for example, one hour) is calculated. Further, the battery parameter calculation unit 65 calculates values of the maximum temperature and the minimum temperature in the soak period by acquiring detection signals from the battery temperature sensor 63 every predetermined cycle during the soak period of the vehicle V.

  The value of the SOC of the battery 3 when no current flows is searched in the battery parameter calculation unit 65 from a predetermined SOC-OCV map from the open circuit voltage (OCV) of the battery 3 detected by the battery voltage sensor 62 Calculated by Further, the value of the SOC of battery 3 when the current is flowing is determined by battery parameter operation unit 65 using a detection signal from sensors 61 to 63 according to a known algorithm (for example, an algorithm using a Kalman filter). It is calculated in consideration of the voltage drop generated due to the internal resistance of 3.

  The discharge depth of the battery 3 refers to the ratio of the amount of discharge to the discharge capacity of the battery 3, and the value thereof uses the integrated value of the charge current and the discharge current detected by the battery current sensor 61 in the battery parameter calculation unit 65. It is calculated appropriately.

  Further, for the value of SOH of the battery 3, for example, the value of the capacity maintenance ratio of the battery 3 (the ratio of the current capacity to the initial capacity of the battery 3) estimated based on a known algorithm The value of (the ratio of the current internal resistance to the initial internal resistance of the battery 3) is used.

  The starter 23 is a cellular motor that starts the engine 1 by the power supplied from the battery 3. When the driver turns on the ignition switch 9 to start the vehicle V, or when restarting the engine 1 after performing the idling stop control described below, the ECU 7 receives the power from the battery 3. It supplies the starter 23 to start the engine 1.

The ECU 7 as an idling stop control device temporarily stops the engine 1 when all of the following automatic stop conditions (a) to (e) are satisfied after the ignition switch 9 is turned on. Run.
(A) The ignition switch 9 is on.
(B) The vehicle speed is equal to or less than the set start speed slightly larger than 0.
(C) The opening degree of the accelerator pedal is almost zero.
(D) The brake pedal is depressed.
(E) The SOC of the battery 3 obtained by the battery sensor unit 6 is equal to or greater than a predetermined start threshold.

Further, after executing the idling stop control, the ECU 7 drives the starter 23 using the electric power of the battery 3 when any of the following automatic return conditions (f) to (h) are satisfied, and the engine 1 Restart the
(F) The depression of the brake pedal has been released.
(G) The SOC of the battery 3 obtained by the battery sensor unit 6 is equal to or less than the end threshold set to a value smaller than the start threshold.
(H) The discharge depth of the battery 3 obtained by the battery sensor unit 6 during the idling stop period exceeds a predetermined allowable discharge depth.

  The ECU 7 performs an I / O interface for A / D converting the detection signal of the sensor, a RAM or ROM for storing various control programs and data, a CPU for executing various arithmetic processing according to the program, and an arithmetic processing result of the CPU The engine 1, the ACG 21, the starter 23, the battery 3, the drive circuit for driving the DCDC converter 53 and the like are constituted.

  Hereinafter, a specific procedure of the deterioration determination control of the battery 3 by the ECU 7 will be described.

  The battery 3, which is a lead storage battery, starts to deteriorate from the time of manufacture (more specifically, at the time of manufacture or when charging / discharging is started after mounting on a vehicle). Gradually decreases from the time of manufacture. FIG. 2 is a view schematically showing the cause of deterioration of the battery 3. As shown in FIG. 2, deterioration factors of the battery 3 are mainly divided into positive grid corrosion, sulfation deterioration, and softening of the active material.

  The positive grid corrosion refers to the progress of the corrosion of the positive grid of the battery 3. When the corrosion of the positive electrode grid progresses, the conductive path in battery 3 is broken, the internal resistance increases, and the charge / discharge amount decreases.

  The sulfation deterioration means that lead sulfate adheres to the surface of the electrode of the battery 3 and this becomes hard. In the battery 3, lead sulfate is generated on the surface of the electrode at the time of discharge, but this lead sulfate basically dissolves in the electrolyte at the time of charge. However, if charge and discharge are repeated for a long time, lead sulfate generated in the electrode is crystallized and hardened. For this reason, if the sulfation deterioration progresses excessively, the internal resistance of the battery 3 increases or the effective surface area of the electrode decreases, and the charge / discharge amount decreases.

  Active material softening refers to softening of the active material applied to the positive electrode grid. When the softening of the positive electrode active material progresses, the active material is partially detached and contracted, the internal resistance of the battery 3 increases, and the charge and discharge amount decreases.

  As described above, the battery 3 is deteriorated mainly due to three factors, but the factors which cause these three deterioration are different. Moreover, in order to extend the life of the battery 3 to a predetermined target life (for example, several years), it is necessary to delay the progress of these three deteriorations, but the specific content of the optimum deterioration suppressing action for delaying each deterioration Depends on the cause of deterioration. Therefore, the ECU 7 uses the values of the battery parameters acquired using the battery sensor unit 6 to determine the progress of the positive electrode grid corrosion, the sulfation deterioration, and the softening of the active material according to different algorithms. In the following, a specific procedure for determining the degree of progress of deterioration in the order of positive electrode grid corrosion, sulfation deterioration, and softening of the active material, and a specific procedure of deterioration suppression action executed to delay the progress of deterioration Explain.

<Deterioration judgment of positive grid corrosion>
First, the factors that cause the deterioration of positive grid corrosion to proceed will be specifically examined.
FIG. 3 is a diagram showing the results of a test conducted to identify factors that cause deterioration of positive grid corrosion. In this test, batteries A, B, and C, which are lead-acid batteries with different specifications, are prepared, and each battery A to C is repeatedly charged and discharged for a predetermined test time under different temperature environments. It decomposed | disassembled and measured the mass of the corroded part among positive electrode gratings. The horizontal axis in FIG. 3 is the temperature [° C.] in this test, and the vertical axis is the amount of corrosion [mass%]. Here, the amount of corrosion means the ratio of the mass of the corroded portion to the mass of the positive electrode grid at the time of new product. That is, the corrosion amount is 0 (mass%) at the time of new product, and then gradually increases as the deterioration progresses.

  As shown in FIG. 3, it is clear that the corrosion amount increases faster as the battery temperature increases in all types of batteries, although there is a difference depending on the type of battery. That is, the progress degree of deterioration of positive grid corrosion can be quantitatively evaluated by the amount of corrosion defined as described above, and it can be said that the amount of corrosion has high correlation with the temperature of battery 3. Therefore, the ECU 7 estimates the value of the amount of corrosion of the battery 3 by using the data regarding the temperature of the battery 3 acquired by the battery sensor unit 6, and further causes the positive grid corrosion of the battery 3 based on this estimated amount of corrosion. Determine the resulting degradation.

  FIG. 4 is a flowchart showing a specific procedure of determining the deterioration of the battery 3 due to the positive electrode grid corrosion. More specifically, FIG. 4 is a flowchart showing a specific procedure of calculating the corrosion amount estimated value indicating the progress of the positive grid corrosion in the ECU 7. The flowchart of FIG. 4 is executed in the ECU 7 every predetermined operation cycle (for example, one hour) until the ignition switch 9 is turned off after the ignition switch 9 is turned on.

  In S1, the ECU 7 determines whether or not the start of the start of the engine 1 has just been started, that is, whether or not the ignition switch 9 has just been turned on. The ECU 7 shifts to S2 when the determination result of S1 is YES, and shifts to S5 when NO.

  In S2 to S4, the ECU 7 estimates an increase in the amount of corrosion in the soak period immediately before the ignition switch 9 is turned on last time until the ignition switch 9 is turned on this time. More specifically, the ECU 7 obtains from the battery sensor unit 6 the maximum temperature value and the minimum temperature value of the battery 3 in the last soak period. In S3, the ECU 7 calculates the average temperature of the battery 3 in the immediately preceding soak period using the maximum temperature value and the minimum temperature value (for example, average temperature = (maximum temperature value + minimum temperature value) / 2). Further, the ECU 7 inputs the calculated average temperature into the relating means for correlating the temperature [° C.] of the battery 3 with the corrosion amount increase rate [ppm] corresponding to the increase amount per unit time of the corrosion amount. Calculate the increase rate value.

  Here, as the association means, specifically, a table, a map, an arithmetic expression, a neural network, etc. which define the correlation between the temperature of the battery 3 and the corrosion rate increase rate when the battery 3 is used at this temperature Is used.

  FIG. 5 is a diagram showing an example of a corrosion amount increase rate calculation table. As shown in FIG. 5, in the corrosion amount increase rate calculation table, the correlation between the temperature of the battery 3 and the corrosion amount increase rate per unit time when the battery 3 is used at this temperature is defined. Such a corrosion amount increase rate calculation table is created in advance by performing a test on a battery of the same type as the battery 3 used in the power supply system S, and is stored in the storage medium of the ECU 7. As described with reference to FIG. 3, the corrosion of the positive grid proceeds faster as the temperature of the battery 3 is higher. For this reason, the corrosion amount increase rate is set to a larger value as the temperature of the battery 3 becomes higher. That is, in the example shown in FIG. 5, a01 <a02 <a03 <... <A18 <a19.

  Returning to FIG. 4, in S4, the ECU 7 multiplies the corrosion rate increase rate calculated using the corrosion rate increase rate calculation table or the like in S3 by the immediately preceding soak period to obtain the corrosion rate in the immediately preceding soak period. The amount of increase [mass%] is calculated, and the process moves to S8.

  In S5, the ECU 7 acquires the average temperature of the battery 3 during traveling from the battery sensor unit 6 to the current calculation cycle from the previous time.

  In S6, the ECU 7 calculates the corrosion rate increase rate during traveling by inputting the average temperature acquired in S5 into the association means such as the corrosion rate increase rate calculation table shown in FIG. 5, for example.

  In S7, the ECU 7 multiplies the calculation period by the corrosion amount increase rate calculated using the corrosion amount increase rate calculation table or the like in S6 to calculate the increase amount of the corrosion amount in this calculation period.

  In S8, the ECU 7 calculates the corrosion amount estimated value by integrating the increase calculated in S4 or S7. The ECU 7 calculates a corrosion amount estimated value that quantitatively represents the progress of positive grid corrosion of the battery 3 according to the above-described procedure, and determines deterioration of the battery 3 by using this corrosion amount estimated value. More specifically, the ECU 7 determines the deterioration of the battery 3 by comparing the calculated corrosion amount estimated value with a predetermined threshold value.

<Action to suppress deterioration of positive grid corrosion>
Next, a specific procedure of the deterioration suppressing action for suppressing the deterioration of the battery 3 caused by the positive electrode grid corrosion as described above will be described.

  FIG. 6 is a diagram for describing a specific procedure of the deterioration suppressing action. In FIG. 6, the horizontal axis represents the time [year] elapsed from the manufacturing time of the battery 3 (more specifically, the manufacturing time or the time when charging / discharging is started after mounting on a vehicle), and the vertical axis is the corrosion amount It is an estimated value [mass%].

  As described above, the battery 3 is deteriorated from the time of its production, and thus the increase in the amount of corrosion can not be stopped. However, the rate of increase in the amount of corrosion is moderate by appropriately executing the deterioration suppressing action described below. It is possible to Also, as described above, the positive grid corrosion progresses faster as the temperature of the battery 3 becomes higher. Therefore, when the estimated corrosion amount calculated as described above exceeds a predetermined threshold, the ECU 7 determines that positive grid corrosion of the battery 3 has progressed to some extent, and the charging current flowing from the ACG 21 to the battery 3 and the battery 3 The generated voltage by the ACG 21 is controlled such that both or any of the discharge currents flowing from the load to the electric loads 51 and 52 become smaller than before the determination of deterioration (deterioration suppressing action for positive grid corrosion). Thus, after the deterioration determination, by controlling the generated voltage so that the charge current or the discharge current becomes smaller than before the deterioration determination, it is possible to suppress the heat generation due to the charge and discharge of the battery 3 after the deterioration determination. Therefore, it is possible to delay the increase of the estimated value of the corrosion amount of the battery 3 and to prolong the life of the battery 3.

  Here, a preferable timing for executing the deterioration suppressing action for suppressing the deterioration caused by such positive electrode grid corrosion will be described. First, in order to extend the life of the battery 3 to the target life, the corrosion amount estimated value is increased from a predetermined initial value, and when the target life has elapsed, the predetermined life determination representing the life of the battery 3 It can be said that reaching a threshold is ideal. That is, it can be said that the corrosion amount estimated value ideally changes as indicated by the one-dot chain line 6a in FIG. For this reason, when the corrosion amount estimated value becomes larger than the threshold which increases according to the time elapsed from the manufacturing time of the battery 3 as shown by the dashed dotted line 6a, that is, the corrosion amount estimated value is hatched in FIG. If it belongs to the degradation region 6b indicated by, the degradation suppression action for the positive grid corrosion is appropriately performed, the increase of the corrosion amount estimated value is delayed, and the corrosion amount estimated value does not exceed the life judgment threshold before reaching the target life. It is preferable to

  However, the rate of progress of positive grid corrosion is considered to change with the seasons because it changes with the temperature of the battery 3. That is, the increase rate of the corrosion amount estimated value is not constant throughout the year, as indicated by the alternate long and short dash line 6a. Therefore, it is preferable that the ECU 7 determines whether the corrosion amount estimated value belongs to the deterioration region 6b, for example, every year, in consideration of the temperature change in each season. Also, as shown by the thick broken line 6c, if the estimated corrosion amount belongs to the deterioration region 6b every year, the deterioration suppression action is executed over a predetermined period, and the increase in the estimated corrosion amount is delayed, It is preferable that the corrosion amount estimated value does not exceed the life determination threshold before the life is reached.

<Deterioration judgment of sulfation deterioration>
Next, a specific procedure of determining the progress degree of the deterioration of the battery 3 due to the sulfation deterioration will be described. First, the factors causing the sulfation deterioration are specifically examined.

  FIGS. 7A and 7B show the results of tests conducted to identify factors that cause sulfation deterioration. FIG. 7A is a diagram showing an increase in the amount of lead sulfate [mass%] when the battery is left standing under three different temperature environments, and FIG. 7B is an amount of lead sulfate when the battery is left standing at three different SOCs. It is a figure which shows the increase in [mass%].

  As shown in FIGS. 7A and 7B, the amount of lead sulfate gradually increases upon standing. Further, the rate of increase in the amount of lead sulfate is faster as the temperature of the battery 3 is higher, and faster as the SOC is lower. That is, the progress speed of the sulfation deterioration increases as the temperature of the battery 3 increases and as the SOC decreases. Therefore, the ECU 7 uses the data regarding the temperature and SOC of the battery 3 acquired by the battery sensor unit 6 to calculate the value of the dimensionless degree of sulfation deterioration that is considered to be approximately proportional to the amount of lead sulfate of the battery 3 Further, based on the value of the sulfation deterioration degree, the deterioration due to the sulfation deterioration of the battery 3 is determined.

  FIG. 8 is a flowchart showing a specific procedure of determining the deterioration of the battery 3 caused by the sulfation deterioration. More specifically, FIG. 8 is a flowchart showing a specific procedure of calculating the value of the sulfation deterioration degree in the ECU 7. The flowchart of FIG. 8 is executed in the ECU 7 every predetermined operation cycle (for example, one hour) until the ignition switch 9 is turned off after the ignition switch 9 is turned on.

  In S21, the ECU 7 determines whether the SOC of the battery 3 obtained from the battery sensor unit 6 is 100% (that is, the battery 3 is fully charged) immediately after the refresh charging described later is performed. . If the determination in S21 is YES, the ECU 7 proceeds to S22, resets the value of the sulfation deterioration degree to 0, which is an initial value, and ends the processing of FIG. If the determination in S21 is NO, the ECU 7 proceeds to S23.

  In step S23, the ECU 7 determines whether the engine 1 has just been started, that is, whether the ignition switch 9 has just been turned on. The ECU 7 proceeds to S25 if the determination result of S23 is YES, and proceeds to S27 if NO.

  In S24 to S26, the ECU 7 estimates an increase in the degree of sulfation deterioration in a soak period immediately before the ignition switch 9 is turned on last time until the ignition switch 9 is turned on this time. More specifically, the ECU 7 acquires the maximum temperature value and the minimum temperature value of the battery 3 and the average SOC in the soak period from the battery sensor unit 6 (S24). In S25, the ECU 7 calculates an average temperature of the battery 3 in the immediately preceding soak period using the maximum temperature value and the minimum temperature value (for example, average temperature = (maximum temperature value + minimum temperature value) / 2). Further, the ECU 7 inputs the combination of the calculated average temperature and the average SOC into association means for associating the combination of the temperature of the battery 3 and the SOC with the increase rate of the sulfation deterioration degree corresponding to the increase amount of the sulfation deterioration degree per unit time. Thus, the sulfation deterioration degree increase rate is calculated.

  Here, as the association means, specifically, a table defining the correlation between the combination of the temperature of the battery 3 and the SOC and the increase rate of the sulfation deterioration degree when the battery 3 is used in the combination of the temperature and the SOC; Maps, arithmetic expressions, neural networks and the like are used.

  FIG. 9 is a diagram showing an example of a sulfation deterioration degree increase rate calculation table. As shown in FIG. 9, in the sulfation deterioration degree increase rate calculation table, the correlation between the combination of the temperature of the battery 3 and the SOC and the increase rate of the sulfation deterioration degree when the battery 3 is used in the combination of the temperature and the SOC Is defined. Such a sulfation deterioration degree increase rate calculation table is created by conducting a test in advance on a battery of the same type as the battery 3 used in the power supply system S, and is stored in the storage medium of the ECU 7. As described with reference to FIGS. 7A and 7B, the sulfation deterioration progresses faster as the temperature of the battery 3 becomes higher and as the SOC of the battery 3 becomes lower. Therefore, the sulfation deterioration degree increasing rate is set to a larger value as the temperature of the battery 3 becomes higher, and set to a larger value as the SOC of the battery 3 becomes lower. That is, in the example shown in FIG. 9, b11 <b12 <... <b16, b21 <b22 <... <b26, ..., b71 <b72 <... <b76, and b11 <b21 <... <b71, b12 < b22 <... <b72 ... ... b16 <b26 <... <b76.

  Referring back to FIG. 8, in S26, the ECU 7 multiplies the value of the sulfation deterioration degree increase rate calculated using the sulfation deterioration degree increase rate calculation table or the like in S25 by the immediately preceding soak period to multiply the value of the last soak period. An increase in the degree of sulfation deterioration in the period is calculated, and the process proceeds to S30.

  In S27, the ECU 7 acquires, from the battery sensor unit 6, the average temperature and the average SOC of the running battery 3 during the current calculation cycle from the previous time.

  In S28, the ECU 7 inputs the combination of the average temperature and the average SOC obtained in S27 into the correlation means such as the sulfation deterioration degree increase rate calculation table shown in FIG. 9 to obtain the value of the sulfation deterioration degree increase rate during traveling. calculate.

  In S29, the ECU 7 multiplies the value of the sulfation deterioration degree increase rate calculated using the sulfation deterioration degree increase rate calculation table or the like in S28 by the operation cycle to calculate the increase in the sulfation deterioration degree in this operation cycle. Do.

  In S30, the ECU 7 calculates the value of the sulfation deterioration degree by integrating the increase calculated in S26 or S29. The ECU 7 calculates the value of the sulfation deterioration degree quantitatively representing the progress degree of the sulfation deterioration of the battery 3 quantitatively with a positive value of 0 or more by the above-described procedure, and uses this value to determine the deterioration of the battery 3 judge. More specifically, the ECU 7 determines the deterioration of the battery 3 by comparing the calculated value of the sulfation deterioration degree with a predetermined threshold value.

<Salfasion degradation degradation suppression action>
Next, a specific procedure of the deterioration suppressing action for suppressing the deterioration of the battery 3 caused by the sulfation deterioration as described above will be described.

  FIG. 10 is a diagram for describing a specific procedure of the deterioration suppressing action using the sulfation deterioration degree. In FIG. 10, the horizontal axis is the time (day) elapsed from the manufacturing time of the battery 3, and the vertical axis is the sulfation deterioration degree (thick solid line) and the battery SOC (thick broken line).

  As described above, the sulfation deterioration proceeds as lead sulfate adheres to the surface of the electrode of the battery 3 and is further hardened, and lead sulfate is electrolytically charged by charging it before it crystallizes. It can be dissolved in liquid. Therefore, when the value of the sulfation deterioration degree calculated according to the procedure described with reference to FIG. 8 exceeds a predetermined threshold (for example, 1000), the ECU 7 determines that the adhesion of lead sulfate has progressed to some extent, The refresh charge for controlling the generated voltage of the ACG 21 is executed so that the battery 3 is fully charged (that is, the SOC is 100%) (action for suppressing deterioration with respect to sulfation deterioration). By performing such refresh charge and forcibly charging the battery 3, it can be actively dissolved in the electrolyte before lead sulfate adhering to the electrode is crystallized. Thereby, crystallization of lead sulfate can be delayed, and thus the life of the battery 3 can be extended.

  Incidentally, as described above, the battery sensor unit 6 can also obtain the SOH of the battery 3. Since the SOH of the battery 3 is considered to decrease as the sulfation deterioration progresses, this SOH can also be used as a parameter indicating the progress degree of the sulfation deterioration similarly to the sulfation deterioration degree. Therefore, the ECU 7 uses the SOH acquired using the battery sensor unit 6 to determine the deterioration of the battery 3.

  FIG. 11 is a diagram for describing a specific procedure of the deterioration suppressing action using SOH. In FIG. 11, the horizontal axis is the time [year] elapsed from the manufacturing time of the battery 3, and the vertical axis is SOH [%].

  In order to extend the life of the battery 3 to the target life as indicated by the alternate long and short dash line 11a in FIG. 11, the SOH decreases from a predetermined initial value, and the life of the battery 3 at the time the target life has elapsed. It can be said that reaching the life determination threshold that represents. Therefore, when the SOH obtained using the battery sensor unit 6 becomes smaller than the threshold value which decreases according to the time elapsed from the manufacturing time of the battery 3 as shown by the dashed dotted line 11a, that is, the SOH However, if it belongs to the degradation region 11b indicated by hatching in FIG. Raise As a result, the SOC of the battery 3 is maintained higher than before the determination of deterioration, so that the rate of increase of the sulfation deterioration degree can be delayed, and thus the life of the battery 3 can be extended to the target life. In addition, by delaying the rate of increase of the sulfation deterioration degree as described above, the frequency at which the above-described refresh charge is performed can be reduced.

<Deterioration judgment of softening of active material>
Next, a specific procedure of determining the degree of progress of deterioration due to the softening of the active material will be described. First, the factors that accelerate the softening of the active material are specifically examined.

  FIG. 12 is a diagram showing the results of a test conducted to identify factors that accelerate the softening of the positive electrode active material. In this test, batteries A, B, and C, which are lead storage batteries with different specifications, are prepared, and the batteries A to C are repeatedly charged and discharged under different depths of discharge to achieve the lifetime charge and discharge amount [Ah]. Was measured. The lifetime charge / discharge amount refers to the sum of the charge amount [Ah] and the discharge amount [Ah] until the end of the battery life. In this test, it was determined that the battery life was exhausted when the voltage drop of the battery was equal to or greater than a predetermined value when the battery was discharged with a current of a predetermined magnitude for a predetermined time.

  In general, since the positive electrode active material is softened every time the charge and discharge is repeated in the lead storage battery, the lifetime charge and discharge amount is limited. Further, as shown in FIG. 12, it was revealed that the lifetime charge / discharge amount decreases as the depth of discharge increases in all types of batteries, although there is a difference depending on the type of battery. That is, it was revealed that the softening of the positive electrode active material proceeds with the increase of the charge / discharge amount, and further accelerates as the depth of discharge increases. This means that the softening of the positive electrode active material can be quantitatively evaluated by using the charge amount, the discharge amount and the discharge depth. Therefore, the ECU 7 uses the data on the charge amount, discharge amount, and depth of discharge of the battery 3 acquired by the battery sensor unit 6 to obtain an effective charge / discharge amount [probably proportional to the softening of the positive electrode active material [ The value of Ah] is calculated, and the deterioration due to the softening of the positive electrode active material of battery 3 is determined based on the value of the effective charge / discharge amount.

  FIG. 13 is a diagram for explaining the procedure for calculating the value of the effective charge / discharge amount in the ECU 7. FIG. 13 is a diagram showing a change in integrated current in a certain driving cycle (hereinafter abbreviated as “DC”) from time t0 to time t1. The upper part of FIG. 13 shows the change of the integrated current calculated with the charging current as positive and the discharge current as negative. The lower part of FIG. 13 shows the charge amount obtained by integrating only the positive charging current (thick The amount of discharge (thick dashed line) obtained by integrating only the discharge current which is solid line) and negative is shown. The ECU 7 calculates the amount of increase in the effective charge / discharge amount defined below and calculates the value of the effective charge / discharge amount by integrating the amount of increase each time one DC ends.

  The effective charge and discharge amount is an amount of electricity obtained by correcting the amount of electricity obtained by combining the amount of charge and the amount of discharge according to the depth of discharge. As described above, the lifetime charge / discharge amount is limited, and the lifetime charge / discharge amount tends to decrease as the depth of discharge increases. Therefore, the ECU 7 introduces the above-mentioned effective charge / discharge amount in order to take into consideration the influence of the discharge depth on the lifetime charge / discharge amount.

The ECU 7 controls the battery sensor unit 6 to set the maximum discharge depth value, which is the maximum value of the discharge depth measured for the current DC, and the charge amount and the discharge amount for the current DC, every time one DC ends. And SOH are calculated, and the increase amount of the effective charge / discharge amount in the current DC is calculated according to the following equation (1).
Increase in effective charge / discharge amount [Ah] =
Charge amount over current DC [Ah] + discharge amount over current DC [Ah]
+ Maximum discharge depth at current DC [%] × SOH at current DC [%] × (deterioration acceleration coefficient-1) (1)

  As described above, the softening of the positive electrode active material proceeds each time the battery 3 performs charge and discharge. Therefore, as shown in the first term and the second term of the right side of the equation (1), the charge amount and the discharge amount are added as an increase of the effective charge / discharge amount as it is.

  Also, as described above, the softening of the positive electrode active material has the property of accelerating as the depth of discharge increases. The third term on the right side in the above equation (1) is introduced in consideration of such characteristics, and is a correction term for correcting the amount of electricity obtained by combining the charge amount and the discharge amount using the maximum discharge depth. Equivalent to. Further, the deterioration acceleration coefficient in this correction term is one or more dimensionless positive coefficients for correcting the amount of electricity to the increase side according to the depth of discharge, and the value thereof is the maximum depth of discharge in the current DC. Is calculated by inputting into the association means which associates the maximum depth of discharge with the deterioration acceleration factor.

  Here, as the association means, specifically, a table, a map, an arithmetic expression, and the like, which define the correlation between the maximum discharge depth in the current DC and the deterioration acceleration coefficient when the battery 3 is used at this maximum discharge depth. And neural networks are used.

  FIG. 14A is a diagram showing an example of a deterioration acceleration coefficient calculation map. As shown in FIG. 14A, the value of the deterioration acceleration coefficient is set to be a larger value as the maximum discharge depth becomes larger. In the example shown in FIG. 14A, the value of the deterioration acceleration coefficient is set to 1 because a large difference was not recognized in the speed of softening of the positive electrode active material between the maximum discharge depth of 0 to c1. Also, when the maximum discharge depth is between c1 and c2, the value of the deterioration acceleration coefficient increases to be d1 larger than 1 at c2, and when the maximum discharge depth is between c2 and c3, the value of the deterioration acceleration coefficient is d1. It is set. When the maximum discharge depth is between c3 and c4, the value of the degradation acceleration coefficient increases to d2 at c4, and when the maximum discharge depth is c4 or more, the value of the degradation acceleration coefficient is set to d2 Ru. Another example of the deterioration acceleration coefficient calculation map is shown in FIGS. 14B and 14C. The value of the deterioration acceleration coefficient may be calculated using the maps as shown in FIGS. 14B and 14C.

  The ECU 7 corrects the increase to the increase side as the maximum depth of discharge becomes larger at the target DC by calculating the increase in the effective charge / discharge amount using such a deterioration acceleration coefficient. The ECU 7 calculates the amount of increase in the effective charge / discharge amount for each DC in accordance with the procedure as described above, and integrates the amount to calculate the value of the effective charge / discharge amount. The effective charge / discharge amount thus calculated corresponds to the lifetime charge / discharge amount in consideration of the depth of discharge for each DC, and can be said to be a parameter indicating the progress of the softening of the positive electrode active material.

<Deterioration suppression action of softening of positive electrode active material>
Next, a specific procedure of the deterioration suppressing action for suppressing the deterioration of the battery 3 caused by the softening of the positive electrode active material as described above will be described.

  FIG. 15 is a diagram for describing a specific procedure of the deterioration suppressing action using the effective charge and discharge amount. In FIG. 15, the horizontal axis represents the time (year) elapsed from the manufacturing time of the battery 3, and the vertical axis represents the effective charge / discharge amount [Ah].

  As described above, the softening of the positive electrode active material has the property of accelerating as the depth of discharge increases. Therefore, the ECU 7 can execute three types of deterioration suppressing actions as the deterioration suppressing actions for suppressing the deterioration of the battery 3 caused by the softening of the positive electrode active material.

  First, the automatic return condition in the idling stop control includes "the discharge depth of the battery 3 obtained by the battery sensor unit 6 during the idling stop period exceeds a predetermined allowable discharge depth" (the above-mentioned automatic return) Condition (h)). Therefore, when the value of the effective charge / discharge amount exceeds the predetermined threshold value, the ECU 7 determines that the deterioration due to the softening of the positive electrode active material has progressed to some extent, and the allowable discharge depth under the automatic recovery condition than before the deterioration determination. Is set to a small value (the first action for suppressing deterioration of the positive electrode active material). The ECU 7 reduces the depth of discharge of the battery 3 by performing such a first deterioration suppressing action at the time of the deterioration determination using the effective charge / discharge amount, thereby delaying the increase of the effective charge / discharge amount. The life of the battery 3 can be extended to the target life.

  Further, when the value of the effective charge / discharge amount exceeds the predetermined threshold value, the ECU 7 determines that the deterioration due to the softening of the positive electrode active material has progressed to some extent, and the target SOC of the battery 3 is higher than before the deterioration determination. It sets (the 2nd deterioration control action to cathode active material softening). When the target SOC is thus set higher than before the deterioration determination, the SOC of the battery 3 after the deterioration determination is maintained higher than before the deterioration determination. On the other hand, although the battery 3 is forcibly charged when the operation request of the specific electric load occurs as described above, by maintaining the SOC of the battery 3 high in this manner, The depth of discharge when an operation request occurs can be reduced. Therefore, the ECU 7 can reduce the depth of discharge of the battery 3 by executing the second deterioration suppressing action as described above at the time of the deterioration determination using the effective charge / discharge amount, thereby increasing the effective charge / discharge amount. It is possible to delay and eventually extend the life of the battery 3 to the target life.

  Further, when the value of the effective charge / discharge amount exceeds the predetermined threshold value, the ECU 7 determines that the deterioration due to the softening of the positive electrode active material has progressed to some extent, and executes the fuel cut of the engine 1 than before the deterioration determination. The power generation voltage of ACG 21 at the time is lowered (the third deterioration suppressing action against the softening of the positive electrode active material). The ECU 7 can make it difficult for the battery 3 to be charged at the time of fuel cut of the engine 1 by executing such a third deterioration suppression action at the time of the deterioration determination using the effective charge and discharge amount. The battery 3 can be made smaller, thereby delaying the increase in the effective charge and discharge amount, and thus the life of the battery 3 can be extended to the target life.

  Here, preferable timings for executing the first to third deterioration suppressing actions for suppressing the deterioration due to the positive electrode lattice softening as described above will be described. First, as shown by the one-dot chain line 15a in FIG. 15, in order to extend the life of the battery 3 to the target life, the value of the effective charge / discharge amount increases from a predetermined initial value, and the target life is elapsed. It can be said that it is ideal to reach the life determination threshold representing the life of the battery 3 at the time when it is reached. Therefore, the ECU 7 each time the value of the effective charge / discharge amount exceeds a plurality of deterioration determination threshold values (two threshold values e1 and e2 are illustrated in FIG. 15) defined between the initial value and the life determination threshold value. It is determined whether the times f1 and f2 determined for each of the deterioration determination threshold values e1 and e2 have not elapsed. In other words, each time the value of the effective charge / discharge amount exceeds the deterioration determination threshold values e1 and e2, the ECU 7 determines whether or not the value belongs to the deterioration region 15b indicated by hatching in FIG. Then, when it is determined that the positive electrode active material softening is progressing faster than the speed set to complete the target life when it is determined that it belongs to the deteriorated area 15b, the first to the above-mentioned first to fourth By appropriately combining and executing any or all of the deterioration suppressing actions in No. 3, the increase rate of the effective charge / discharge amount thereafter is delayed. Thereby, the life of the battery 3 can be extended to the target life. In the line 15c of FIG. 15, when the value of the effective charge / discharge amount exceeds the deterioration determination threshold value e1, the time f1 has not elapsed, and the first to third deterioration suppression actions are executed, and thereafter the effective charge / discharge Since the time f2 has not elapsed even when the value of the amount exceeds the deterioration determination threshold value e2, the first to third deterioration suppressing actions are executed. According to this example, by performing these deterioration suppression actions at appropriate timing using the effective charge / discharge amount, the effective charge / discharge amount does not exceed the life determination threshold when the target life has elapsed, and the target life You can

  As described above, in the power supply system S of the present embodiment, the amount of corrosion is introduced as a parameter that quantitatively indicates the degree of deterioration of the battery 3 due to positive grid corrosion, and the degree of deterioration due to sulfation deterioration of the battery 3 is quantified. The sulfation deterioration degree is introduced as a parameter shown in the figure, and the effective charge / discharge amount is introduced as a parameter showing quantitatively the deterioration degree of the battery 3 due to the softening of the positive electrode active material. By appropriately executing the degradation suppression action determined for that, the life of the battery 3 can be extended to the target life.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. The detailed configuration may be changed as appropriate within the scope of the present invention.

V: Vehicle 1: Engine (internal combustion engine)
S: Power supply system 21: ACG (generator)
23 ... starter 3 ... battery (lead battery)
51 ... 1st electric load (electric load)
52 ... 2nd electrical load (electrical load)
53 ... DC DC converter (electrical load)
6 ... Battery sensor unit (battery condition acquisition device)
7 ... ECU (generator control device, idling stop control device, battery deterioration determination device)
9 ... Ignition switch

Claims (6)

A lead battery that supplies power to the vehicle's electrical load;
A battery state acquisition device for acquiring a value related to the state of the lead battery;
A battery deterioration determining device that determines the deterioration of the lead battery based on the value acquired by the battery state acquiring device;
The battery state acquisition device acquires the value of the temperature of the lead battery,
The said battery deterioration determination apparatus determines the deterioration of the said lead battery based on the temperature acquisition value by the said battery state acquisition apparatus, The power supply system characterized by the above-mentioned. The battery state acquisition device is the lead at the time of traveling possible from the time the vehicle is allowed to travel to the time it is not traveled and at the time of soak from the time the vehicle is not traveled to the time it is allowed to travel. Get the battery temperature value,
The power supply system according to claim 1, wherein the battery deterioration determining device determines the deterioration of the lead battery based on a temperature acquisition value at the time of traveling and the temperature acquisition value at the time of soaking.   The battery deterioration determination device includes association means for associating the temperature of the lead battery with an increase per unit time of a deterioration parameter indicating the progress of deterioration of the lead battery, and the temperature acquisition value by the battery state acquisition device is The value of the deterioration parameter is calculated by integrating the increment per unit time obtained by inputting to the association means, and the deterioration of the lead battery is determined based on the value of the deterioration parameter. The power supply system according to claim 1 or 2.   The power supply system according to claim 3, wherein the association unit increases the increase as the temperature acquisition value by the battery state acquisition device increases. A generator connected to the lead battery,
A generator control unit that controls the voltage generated by the generator;
When the battery deterioration determining device determines that the lead battery has deteriorated, the generator control device determines a charging current flowing from the generator to the lead battery and a discharging current flowing from the lead battery to the electric load The power supply system according to any one of claims 1 to 4, characterized in that the generated voltage is controlled such that both or any one of them becomes smaller than before it is determined that the lead battery has deteriorated.   The power supply system according to claim 3 or 4, wherein the deterioration parameter is a parameter indicating a degree of progress of deterioration due to corrosion of an electrode of the lead battery.

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