JP2007221868A - Battery charging apparatus and battery charging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform optimum charge control based on the degree of deterioration of the battery of a battery charging apparatus. <P>SOLUTION: A battery deterioration degree detection means 1a detects the degree of deterioration of a battery 2. A battery charge amount computing means 1b computes the charge amount to the battery 2. A correction storage means 1c stores the correction for correcting the charge amount, according to the degree of deterioration. A charge amount correcting means 1d acquires a correction geared to the degree of deterioration detected by the battery deterioration degree detecting means 1a, from the correction storage means 1c, and corrects the charge amount. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a battery charging device and a battery charging method, and more particularly to a battery charging device and a battery charging method for charging a vehicle battery.

In recent years, with the rapid spread of automobiles, there is an increasing need for improving the comfort, safety and convenience of automobiles. For this reason, the number of in-vehicle electrical components such as air conditioners and navigations attached to automobiles is increasing rapidly. As a result, the load on the battery is increased, and charging control according to the state of the battery such as a voltage drop or deterioration has become necessary. In view of this, a battery charging device has been proposed that performs charge control to vary the current when a voltage near full charge is reached so as not to overcharge the battery (see Patent Document 1).
Japanese Patent Laid-Open No. 7-115733

  However, since the battery charging device shown in the above document performs normal charging control until the battery voltage reaches a voltage near full charge, charging according to the degree of deterioration of the battery is not performed until then. There is a problem that the battery may run out.

  The present invention has been made in view of these points, and an object of the present invention is to provide a battery charging apparatus capable of performing optimal charging control according to the degree of deterioration of the battery.

  In the present invention, in order to solve the above problem, in a battery charging apparatus for charging a battery of a vehicle, a battery deterioration level detecting means for detecting a deterioration level of the battery and a battery charge amount for calculating a charge amount for charging the battery. There is provided a battery charging device comprising: a calculating means; and a charge amount correcting means for correcting the charge amount according to the degree of deterioration detected by the battery deterioration degree detecting means.

  Thereby, the battery deterioration degree detecting means detects the deterioration degree of the battery. The battery charge amount calculation means calculates a charge amount for charging the battery. The charge amount correcting means corrects the charge amount according to the degree of deterioration detected by the battery deterioration degree detecting means.

  According to the battery charger of the present invention, the degree of deterioration of the battery is detected, and the amount of charge for fully charging the battery is calculated. And the correction value according to the detected deterioration degree is acquired from the correction value storing means, and the charge amount is corrected.

  Therefore, by charging according to the degree of deterioration of the battery, it is possible to appropriately charge the battery that has become difficult to be charged due to deterioration, and it is possible to prevent the battery from rising.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a conceptual diagram of the invention applied to this embodiment. As shown in FIG. 1, a battery charger 1, a battery 2, and an alternator 3 are connected to each other. The battery charging apparatus 1 includes a battery deterioration level detection unit 1a, a battery charge amount calculation unit 1b, a correction value storage unit 1c, and a charge amount correction unit 1d.

  The battery deterioration level detection means 1 a detects the deterioration level of the battery 2. The battery charge amount calculation means 1b calculates a charge amount necessary for fully charging the battery 2. The correction value storage unit 1 c stores in advance a correction value for correcting the charge amount according to the degree of deterioration of the battery 2. When the charge amount correction unit 1d receives the deterioration level of the battery 2 from the battery deterioration level detection unit 1a, the charge amount correction unit 1d reads a correction value corresponding to the deterioration level from the correction value storage unit 1c. Then, the charge amount is corrected by multiplying the charge amount calculated by the battery charge amount calculating means 1b by the correction value. The alternator 3 generates power in accordance with the charge amount corrected by the charge amount correction unit 1 d and charges the battery 2.

  Thereby, the battery deterioration degree detection means 1a detects the deterioration degree of the battery 2, and the battery charge amount calculation means 1b calculates the charge amount necessary for fully charging the battery 2. Since the charge amount is corrected by the correction value corresponding to the degree of deterioration stored in advance in the correction value storage means 1c, the charge amount increased by correction in consideration of the fact that the battery 2 has a reduced current acceptance capability due to deterioration. Is generated by the alternator 3 and the battery 2 is charged. Therefore, the battery that has become difficult to charge due to deterioration can be appropriately charged, and the battery can be prevented from running out.

Next, an embodiment in which the battery charging device of one embodiment according to the present invention is applied to a master ECU will be described in detail with reference to the drawings.
FIG. 2 is a diagram illustrating a system configuration example according to the present embodiment. As shown in FIG. 2, a master ECU (Electronic Control Unit) 10, a battery 20, and an alternator (ALT) 30 are connected via a bus 40. In addition, a navigation 50 is connected to the master ECU 10, and a voltmeter 21, an ammeter 22, and a liquid thermometer 23 are connected to the battery 20.

  Master ECU 10 detects the voltage and current of battery 20 from voltmeter 21 and ammeter 22, and calculates the actual internal resistance of battery 20. The master ECU 10 detects the battery liquid temperature of the battery 20 from the liquid thermometer 23. Then, the theoretical internal resistance that is stored in advance in association with the battery liquid temperature and at which the battery 20 is normal is acquired. Further, the deterioration degree of the battery 20 is detected by comparing the actual internal resistance and the theoretical internal resistance.

  Then, the amount of electricity for fully charging the battery 20 is calculated from the battery capacity, the target charging voltage of the battery 20, and the detected voltage, and the amount of electricity to be charged in the battery 20 is calculated by correcting the amount of deterioration. .

  The master ECU 10 can also detect the running state of the vehicle. The master ECU 10 stores in advance the voltage and current that the battery 20 should generate in association with the running state and the battery liquid temperature of the battery 20. The master ECU 10 calculates the voltage and current to be generated by the battery 20 from the detected traveling state and battery liquid temperature, and corrects the calculated voltage and current according to the degree of deterioration. Then, the work to be output by the alternator 30 is calculated from the corrected voltage and current, and an instruction is given to the alternator 30.

  FIG. 3 is a diagram illustrating a hardware configuration example of the master ECU used in the present embodiment. As shown in FIG. 3, the master ECU 10 includes a microcomputer 11, an I / F (InterFace) 12, and a bus 13, and is connected to, for example, an external bus 40 via the I / F 12. Yes.

  The microcomputer 11 includes a CPU (Central Processing Unit) 11a, a ROM (Read Only Memory) 11b, and a RAM (Random Access Memory) 11c. As for master ECU10, the whole apparatus is controlled by CPU11a. A ROM 11b and a RAM 11c are connected to the CPU 11a via a bus 11d inside the microcomputer 11.

  The RAM 11c temporarily stores at least part of an OS (Operating System) program and application programs to be executed by the CPU 11a. The RAM 11c stores various data necessary for processing by the CPU 11a. The ROM 11b stores an OS and application programs.

  Note that the hardware of the master ECU 10 is not limited to the configuration shown in FIG. For example, a ROM may be connected to the bus 13 and the OS and application programs may be stored in the ROM. Alternatively, a RAM may be connected to the bus 13 and data may be temporarily stored in the RAM. With the hardware configuration as described above, the processing functions of the present embodiment can be realized.

Next, processing functions of the master ECU 10 will be described.
FIG. 4 is a diagram showing processing functions of the master ECU of the present embodiment. As shown in FIG. 4, the master ECU 10 includes a battery state detection unit 10a, an internal resistance calculation unit 10b, an internal resistance storage unit 10c, a deterioration degree calculation unit 10d, a battery information storage unit 10e, an electric quantity calculation unit 10f, and a correction value storage. 10g, charge amount correction unit 10h, time calculation unit 10i, current determination unit 10j, running state detection unit 10k, voltage characteristic storage unit 101, current characteristic storage unit 10m, and voltage / current determination unit 10n.

  The battery state detection unit 10 a detects the voltage, current, and battery liquid temperature of the battery 20 from the voltmeter 21, ammeter 22, and liquid thermometer 23 that are connected to the battery 20. While the engine start signal is ON, the battery state detection unit 10a detects the voltage, current, and battery of the battery 20 from the voltmeter 21, ammeter 22, and liquid temperature gauge 23 connected to the battery 20 at a constant sampling period. Sample the liquid temperature. FIG. 5 shows the relationship between the engine start signal and the sampling of voltage and current.

FIG. 5 is a diagram showing how the engine start signal, voltage, and current are sampled. FIG. 5A is a diagram showing an engine start signal, FIG. 5B is a diagram showing a change in voltage and a state of sampling, and FIG. 5C is a diagram showing a change in current and sampling. FIG. As shown in FIG. 5 (A), when the engine start signal is turned on, the voltage and current are sampled at a constant period as shown in FIGS. 5 (B) and 5 (C). The current and voltage are sampled n times while the engine start signal is ON, and the voltage and current detected at the first time are V ₁ and I ₁ , respectively. was a V _2, I _2, respectively, the voltage detected in the third time, current and V _3, I ₃ respectively, the voltage detected at the n-th, current respectively V _n, and I _n. Note that the state where the engine start signal is ON indicates a state where the starter is driven.

Returning to FIG. 4, the processing function of the master ECU 10 will be described.
The internal resistance calculation unit 10b receives the voltage and current of the battery 20 from the battery state detection unit 10a and calculates the internal resistance. For example, the internal resistance in each sampling is calculated from the voltages and currents sampled by the battery state detection unit 10a using the following equations (1) to (3), and the internal resistance in each sampling is calculated using the equation (4). To calculate the actual internal resistance.

R ₁ = (V ₂ −V ₁ ) / (I ₂ −I ₁ ) (1)
R ₂ = (V ₃ −V ₂ ) / (I ₃ −I ₂ ) (2)
...
R _n-1 = (V _n −V _n−1 ) / (I _n −I _n−1 ) (3)
R = (R ₁ + R ₂ +... + R _n-1 ) / (n-1) (4)
The internal resistance storage unit 10c stores in advance the theoretical internal resistance when the battery 20 is normal in association with the battery liquid temperature.

  When the deterioration degree calculation unit 10d receives the internal resistance from the internal resistance calculation unit 10b, the deterioration degree calculation unit 10d receives the battery liquid temperature from the battery state detection unit 10a. Similarly to the voltage and current, the battery liquid temperature is also sampled n times while the engine start signal is ON.

The first battery fluid temperature as T _1, the second battery fluid temperature as T _2, when the n-th battery liquid temperature is T _n, the battery at each sampling detected using Equation (5) below The battery liquid temperature is determined by averaging the liquid temperature.

T = (T ₁ + T ₂ +... + T _n ) / n (5)
Then, the deterioration degree calculation unit 10d receives the theoretical internal resistance corresponding to the battery liquid temperature obtained from the internal resistance storage unit 10c, and compares the calculated actual internal resistance with the theoretical internal resistance stored in advance. To calculate the degree of deterioration. A graph used when calculating the degree of deterioration is shown in FIG.

  FIG. 6 is a diagram showing the relationship between battery liquid temperature and internal resistance. As shown in FIG. 6, the liquid temperature-internal resistance graph 60 indicates that the internal resistance changes depending on the battery liquid temperature, and the internal resistance rapidly increases as the battery liquid temperature decreases.

  The graph indicated by the solid line is a graph showing the relationship between the battery liquid temperature and the internal resistance when the battery 20 is normal, and the graph indicated by the broken line is the battery liquid temperature when the battery 20 is deteriorated. It is a graph which shows the relationship between and internal resistance. It shows that when the battery liquid temperature is the same, the internal resistance increases when the battery 20 deteriorates.

  It can be said that the deviation between the graph indicated by the solid line and the graph indicated by the broken line indicates the degree of deterioration of the battery 20. That is, the deterioration degree calculation unit 10d determines the degree of deterioration of the battery 20 by checking how far the internal resistance calculated by the internal resistance calculation unit 10b is away from the internal resistance stored in the internal resistance storage unit 10c. calculate.

Returning to FIG. 4, the processing function of the master ECU 10 will be described.
The battery information storage unit 10e stores a target battery voltage and a battery capacity of the battery 20. The target battery voltage is a target value of the battery voltage when charging the battery 20.

  When the destination is set in the navigation 50, the electric quantity calculation unit 10f receives the target battery voltage and the battery capacity from the battery information storage unit 10e, and the electric quantity to be charged in the battery 20 (the battery 20 is fully charged). The amount of electricity required for

  In the correction value storage unit 10g, a correction value for correcting the current and voltage to be generated by the alternator 30 in accordance with the degree of deterioration of the battery 20 is stored in advance in association with the degree of deterioration. In addition, a correction value for correcting the amount of electricity necessary for the battery 20 to be fully charged according to the degree of deterioration of the battery 20 is stored in advance in association with the degree of deterioration. A graph used when obtaining a correction value from the degree of deterioration is shown in FIG.

  FIG. 7 is a diagram illustrating an example of the relationship between the deterioration degree of the battery and the correction value. As shown in FIG. 7, the deterioration level-correction value graph 61 shows that the correction value changes depending on the deterioration level, and the correction value decreases as the deterioration level decreases. When the degree of deterioration becomes 0, the correction value becomes 1. That is, when there is no deterioration, it is not necessary to correct the electric quantity, voltage, and current determined by the electric quantity calculation unit 10f and the voltage / current determination unit 10n.

Returning to FIG. 4, the processing function of the master ECU 10 will be described.
When the charge amount correction unit 10h receives the deterioration level from the deterioration level calculation unit 10d, the charge amount correction unit 10h receives a correction value corresponding to the deterioration level from the correction value storage unit 10g. Then, the amount of electricity calculated by the amount of electricity calculation unit 10f is corrected by the correction value received from the correction value storage unit 10g.

  When the voltage / current to be generated by the alternator 30 is received from the voltage / current determination unit 10n, the received voltage and current are corrected by the correction value corresponding to the degree of deterioration read from the correction value storage unit 10g. 30 is instructed to generate the corrected voltage and current. The voltage / current determination unit 10n will be described later.

  The time calculation unit 10 i calculates how much time can be charged from the travel information from the current location to the destination set in the navigation 50. The travel information is, for example, information on the distance from the current location to the destination and the distance on the uphill that is difficult to charge. When the destination is set for the navigation 50 and the route is determined, the required time to the destination is calculated from the distance to the destination. The chargeable time can be calculated by subtracting the time required to travel on an uphill that is difficult to charge from the calculated time required for the entire process.

  When the current determination unit 10j receives the corrected electricity amount from the charge amount correction unit 10h and the chargeable time calculated by the time calculation unit 10i, the current determination unit 10j divides each to obtain the current to be generated by the alternator 30 per time. Is calculated.

  The traveling state detector 10k detects the traveling state of the vehicle. For example, it detects whether the vehicle is in deceleration, racing, idle, constant speed, or acceleration. For example, when the vehicle is accelerating, much of the energy generated by the engine is used to accelerate the vehicle.

  On the other hand, when the vehicle is decelerating or in a racing state, much of the energy generated by the engine can be used for power generation. Further, when the vehicle is decelerating, the regenerative current can be used for charging. In other words, it is possible to detect how much energy generated by the engine can be used for power generation by detecting the state of the vehicle.

  In the voltage characteristic storage unit 101, a voltage to be generated by the alternator 30 is stored in advance in association with the battery liquid temperature. In the current characteristic storage unit 10m, a current to be generated by the alternator 30 is stored in advance in association with the battery liquid temperature.

  When the voltage / current determination unit 10n receives the traveling state of the vehicle from the traveling state detection unit 10k and receives the battery fluid temperature from the battery state detection unit 10a, the voltage / current determination unit 10n corresponds to the traveling state stored in the voltage characteristic storage unit 10l. A voltage to be generated by the alternator 30 is determined using a graph showing the characteristics of. Further, the current to be generated by the alternator 30 is determined using a graph indicating the current characteristics corresponding to the running state stored in the current characteristic storage unit 10m. 8 and 9 show characteristic graphs used when the voltage / current determination unit 10n determines the voltage or current from the running state of the vehicle and the battery liquid temperature.

  FIG. 8 is a diagram showing the relationship between the battery liquid temperature and the voltage to be generated by the alternator. As shown in FIG. 8, the liquid temperature-voltage graph 62 shows that the voltage that the alternator 30 should generate depends on the battery liquid temperature. The three graphs show the relationship between the battery liquid temperature and the voltage to be generated by the alternator 30 when the vehicle is decelerated / raced, idle / constant speed, and accelerated, respectively.

  When the vehicle decelerates and races, it is not necessary to consume the energy output from the engine as the driving force of the vehicle, so that it can be sufficiently used as the energy for driving the alternator 30. Therefore, during deceleration and racing, the voltage that the alternator 30 should generate is set high. On the other hand, when the vehicle is accelerating, priority is given to consuming the energy output from the engine as the driving force of the vehicle, so that the energy for driving the alternator 30 is not sufficient. Therefore, during acceleration, the voltage to be generated by the alternator 30 is set low. In addition, when the battery liquid temperature is low, the voltage to be generated by the alternator 30 increases when the vehicle is decelerating / racing, idling / constant speed, or during acceleration.

  FIG. 9 is a diagram showing the relationship between the battery liquid temperature and the current to be generated by the alternator. As shown in FIG. 9, the liquid temperature-current graph 63 shows that the current that the alternator 30 should generate depends on the battery liquid temperature. Similarly to the liquid temperature-voltage graph 62 shown in FIG. 8, the three graphs from the top respectively show the battery liquid temperature when the vehicle is decelerating / racing, idle / constant speed, and acceleration, and the alternator 30 generates power. The relationship of the electric current which should be shown is shown.

  When the vehicle decelerates and races, it is not necessary to consume the energy output from the engine as the driving force of the vehicle, so that it can be sufficiently used as the energy for driving the alternator 30. Therefore, during deceleration / racing, the current to be generated by the alternator 30 is set high.

  On the other hand, when the vehicle is accelerating, priority is given to consuming the energy output from the engine as the driving force of the vehicle, so that the energy for driving the alternator 30 is not sufficient. Therefore, during acceleration, the current to be generated by the alternator 30 is set low. Further, the current to be generated by the alternator 30 increases when the battery liquid temperature decreases at any time during deceleration / racing of the vehicle, idling / constant speed, and acceleration.

Next, a specific example of data stored in the correction value storage unit 10g will be described.
FIG. 10 is a diagram illustrating a data structure of a correction value table stored in the correction value storage unit. As shown in FIG. 10, the correction value table 64 has columns of deviation and correction value. Information arranged in the vertical direction of each column is associated with each other. In the deviation column, the deviation of the liquid temperature-internal resistance graph 60 shown in FIG. 6 is set from 0 mΩ to 10 mΩ at intervals of 2 mΩ. In the correction value column, 1 is set to 1.5 at intervals of 0.1.

The following processing is performed by the master ECU 10 having the above functions and data.
FIG. 11 is a flowchart showing a procedure of processing for calculating the degree of deterioration of the battery by the master ECU. In the following, the process illustrated in FIG. 11 will be described in order of step number.

  [Step S11] The battery state detector 10a determines whether or not the engine is started. If the engine has started, the process proceeds to step S12. If the engine has not started, the process ends.

[Step S12] The battery state detector 10a detects the voltage, current, and battery liquid temperature of the battery 20 from the voltmeter 21, ammeter 22, and liquid thermometer 23.
[Step S13] The internal resistance calculator 10b calculates the internal resistance of the battery 20 when the voltage and current detected by the battery state detector 10a are acquired. The deterioration degree calculation unit 10d acquires the battery liquid temperature detected by the battery state detection unit 10a. And the theoretical internal resistance corresponding to the battery liquid temperature acquired from the battery state detection part 10a memorize | stored in the internal resistance memory | storage part 10c is acquired. Then, the deterioration degree calculation unit 10d calculates the deterioration degree from the deviation obtained by subtracting the theoretical internal resistance from the calculated internal resistance.

FIG. 12 shows a process for calculating the deterioration level as described above and correcting the charge amount using a correction value corresponding to the deterioration level.
FIG. 12 is a flowchart showing a procedure of processing for controlling the amount of battery charging performed by the master ECU. In the following, the process illustrated in FIG. 12 will be described in order of step number.

  [Step S21] The battery state detection unit 10a determines whether or not a destination is set in the navigation 50. When a destination is set in the navigation 50, a route search from the current location to the destination is performed, and the distance to the destination and the estimated time are calculated by determining the route. If the destination is set in navigation 50, the process proceeds to step S22. If not set, the process proceeds to step S25 and step S27.

[Step S22] The battery state detector 10a detects the voltage of the battery 20 from the voltmeter 21. The electric quantity calculation unit 10f acquires the voltage detected by the battery state detection unit 10a. Further, the target battery voltage and the battery capacity of the battery 20 are acquired from the battery information storage unit 10e. Then, the amount of electricity is calculated from the acquired voltage, target battery voltage, and battery capacity using the following equation (6).
(Target battery voltage-acquired voltage) x battery capacity per unit volt = quantity of electricity
……… (6)
When the charge amount correction unit 10h acquires the amount of electricity calculated by the amount of electricity calculation unit 10f and acquires the degree of deterioration from the deterioration degree calculation unit 10d, the charge amount correction unit 10h acquires a correction value corresponding to the degree of deterioration acquired from the correction value storage unit 10g. To do. Then, the amount of electricity is corrected by multiplying the acquired correction value.

  [Step S23] The time calculation unit 10i calculates how much time can be charged from the travel information from the current location to the destination set in the navigation 50. The travel information is, for example, information on the distance from the current location to the destination and the distance on the uphill that is difficult to charge. Due to the presence of the stroke information, the chargeable time can be calculated by subtracting the time required to travel on the uphill that is difficult to charge from the time required for the entire stroke.

  [Step S24] The current determination unit 10j acquires the corrected charge amount from the charge amount correction unit 10h. Moreover, the current determination unit 10j acquires the charging time calculated from the time calculation unit 10i. Then, the current to be generated by the alternator 30 is determined by dividing the corrected charging amount by the charging time.

[Step S25] The traveling state detector 10k detects the traveling state of the vehicle.
[Step S26] When the voltage / current determination unit 10n receives the travel state of the vehicle from the travel state detection unit 10k, the voltage / current determination unit 10n receives the battery fluid temperature from the battery state detection unit 10a. Then, the voltage / current determination unit 10n uses the liquid temperature-current graph 63 to determine a target current value to be generated by the alternator 30 from the running state and the battery liquid temperature. When the charge amount correction unit 10h receives the deterioration level from the deterioration level calculation unit 10d and receives the current value determined from the voltage / current determination unit 10n, the charge amount correction unit 10h corrects the current value using the received deterioration level.

[Step S27] The traveling state detector 10k detects the traveling state of the vehicle.
[Step S28] When the voltage / current determination unit 10n receives the travel state of the vehicle from the travel state detection unit 10k, the voltage / current determination unit 10n receives the battery liquid temperature from the battery state detection unit 10a. Then, the voltage / current determination unit 10n determines a target voltage value to be generated by the alternator 30 from the running state and the battery liquid temperature using the liquid temperature-voltage graph 62. When the charge amount correction unit 10h receives the deterioration level from the deterioration level calculation unit 10d and receives the voltage value determined from the voltage / current determination unit 10n, the charge amount correction unit 10h corrects the voltage value using the received deterioration level.

[Step S29] After correcting the voltage and current, the charge amount correction unit 10h calculates the amount of power to be generated by the alternator 30 using the following equation (7). Then, it instructs the alternator 30 to output the calculated power generation amount.
(Target voltage value−Voltage value of battery 20) × Target current value = Power generation amount (7)
By performing the above-described processing, the calculated amount of electricity or the determined voltage and current is corrected according to the degree of deterioration of the battery 20, so that it is difficult to charge the battery 20 due to deterioration. However, it is possible to appropriately charge the battery and prevent the battery from running out.

  Further, by obtaining the travel time from the navigation 50 to the destination and dividing the calculated amount of electricity by the travel time, the battery 20 can be fully charged with the travel time to the destination. Further, by subtracting the time for traveling on an uphill that is difficult to charge from the travel time to the destination, the battery 20 can be fully charged in the travel time to the destination more preferably. Further, by detecting the traveling state and the battery liquid temperature and determining the current and voltage from the traveling state and the battery liquid temperature, the battery 20 can be charged according to the traveling state.

  Although the processing from step S25 to step S28 in FIG. 12 is shown to be performed in parallel, the processing of step S25 and step S26 and the processing of step S27 and step S28 may be performed in order.

  In addition, in a vehicle in which the navigation 50 is not mounted, the current and voltage are determined according to the traveling state, as in the case where the destination is not set. Further, in step S23 of FIG. 12, the charging time calculated by the time calculation unit 10i is traveling on an uphill that is difficult to charge from the required time to the destination calculated when the destination is set for the navigation 50. However, a refresh charging time incorporated in advance in the vehicle may be used as the charging time. Note that the refresh charging time is a time for charging the power generation voltage of the alternator 30 to a high value around a full charge once a week, for example.

  Since the refresh charging time can be set as the charging time, the electric quantity calculation unit 10f can be used for a vehicle not equipped with the navigation 50 or a vehicle equipped with the navigation 50 but having no destination set. The amount is calculated, the charge amount correction unit 10h corrects the amount of electricity, the current determination unit 10j determines the current with the charge time as the refresh charge time, and the alternator 30 is controlled to generate the determined current. Is also possible. Further, the time for traveling on a difficult-to-charge road for subtraction from the travel time for the entire stroke is not necessarily the time for traveling uphill as long as it is difficult to charge.

  Note that the battery charging device described as the above embodiment may be integrated into a power management control device and an engine control device, or may be a function provided in an integrated control device in which several types of control are integrated.

It is a conceptual diagram of the invention applied to this Embodiment. It is a figure which shows the system configuration example which concerns on this Embodiment. It is a figure which shows the hardware structural example of master ECU used for this Embodiment. It is a figure which shows the processing function of master ECU of this Embodiment. It is the figure which showed the mode of sampling of an engine starting signal, a voltage, and an electric current. It is a figure which shows the relationship between battery liquid temperature and internal resistance. It is a figure which shows an example of the relationship between the deterioration degree of a battery, and a correction value. It is a figure which shows the relationship between a battery liquid temperature and the voltage which an alternator should generate | occur | produce. It is a figure which shows the relationship between battery liquid temperature and the electric current which an alternator should generate | occur | produce. It is a figure which shows the data structure of the correction value table memorize | stored in the correction value memory | storage part. It is a flowchart which shows the procedure of the process which calculates the deterioration degree of the battery by master ECU. It is a flowchart which shows the procedure of the process which controls the charge amount of the battery charge by master ECU.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery charging device 1a Battery deterioration level detection means 1b Battery charge amount calculation means 1c Correction value storage means 1d Charge amount correction means 2 Battery 3 Alternator

Claims (7)

In a battery charger for charging a vehicle battery,
Battery deterioration degree detecting means for detecting the deterioration degree of the battery;
Battery charge amount calculating means for calculating a charge amount for charging the battery;
Charge amount correction means for correcting the charge amount according to the deterioration degree detected by the battery deterioration degree detection means;
A battery charger characterized by comprising: Further comprising internal resistance storage means for storing in advance the theoretical internal resistance at which the battery is normal for each temperature of the battery,
The battery deterioration degree detecting means is
Battery status acquisition means for acquiring the voltage, current and temperature of the battery;
An internal resistance calculating means for calculating an actual internal resistance of the battery from the voltage and the current;
Deterioration degree calculation means for obtaining a theoretical internal resistance corresponding to the temperature from the internal resistance storage means and calculating the deterioration degree in comparison with the calculated actual internal resistance;
The battery charging device according to claim 1, comprising: Charging time calculating means for calculating a charging time capable of charging the battery;
Current calculation means for calculating a current value necessary for full charge of the battery from the charging time and the corrected charge amount corrected by the charge amount correction means;
The battery charger according to claim 1, further comprising:   4. The battery charging apparatus according to claim 3, wherein the charging time calculation means sets the traveling time to the arrival destination of the vehicle as the charging time.   The battery charging device according to claim 3, wherein the charging time calculation unit sets a refresh charging time of the vehicle as the charging time. The battery charge amount calculating means includes
Traveling state detecting means for detecting the traveling state of the vehicle;
Voltage characteristic storage means in which the voltage with respect to the temperature is stored for each traveling state;
Current characteristic storage means in which the current with respect to the temperature is stored for each traveling state;
Voltage determining means for acquiring the traveling state from the traveling state detecting means, acquiring the temperature from the battery state acquiring means, and determining a voltage corresponding to the traveling state and the temperature from the voltage characteristic storage means;
Current determining means for acquiring the traveling state from the traveling state detecting means, acquiring the temperature from the battery state acquiring means, and determining a current corresponding to the traveling state and the temperature from the current characteristic storage means;
The battery charger according to claim 2, further comprising: In a battery charging method for charging a vehicle battery,
A step of detecting a degree of deterioration of the battery;
Battery charge amount calculating means calculating a charge amount for charging the battery;
A charge amount correcting unit correcting the charge amount according to the deterioration level detected by the battery deterioration level detecting unit;
The battery charging method characterized by including.

Images