JP2008260345A - Battery condition determination device and automotive lead battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery condition determination device added with convenience on use. <P>SOLUTION: When a lead battery 10 is mounted on a vehicle and an activation circuit 11 receives a descending signal of a voltage of an output terminal by feeding electric power from the lead battery 10 to a cell motor at first, the activation circuit 11 activates a unit 1 making the received signal as a trigger. Therefore, power consumption of the lead battery 10 to activation of the unit is suppressed. When the unit 1 is activated, a voltage of the lead battery 10 is measured by an operation part 13 and the battery state of the lead battery is determined based on the measured voltage. After the unit 1 is activated, when a switch arranged on an operation display part 2 is pushed down for 5 seconds or more, operation of the unit 1 is stopped making the signal as a trigger, data in EEPROM are eliminated and it is returned to the initial state. Action of the unit 1 is stopped, and the lead battery 10 can be transferred to the other vehicle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a battery state determination device and a lead battery for automobiles, and more particularly, voltage measurement means for measuring the voltage of the lead battery for automobiles, and determination of the battery state of the lead battery based on the voltage measured by the voltage measurement means. The present invention relates to a battery state determination device that includes state determination means and operates with electric power supplied from a lead battery, and an automotive lead battery that includes the battery state determination device.

  A lead storage battery (hereinafter simply referred to as a lead battery) mounted on an automobile is an important component in terms of ensuring engine start-up in a gasoline engine vehicle, a diesel engine vehicle, and the like. In recent years, with the spread of in-vehicle information devices such as car navigation and the electrification of auxiliary equipment such as electric power steering, the number of in-vehicle electrical components has increased, and lead batteries are also required to respond to the increasing power supply. .

  It is inevitable that the electrical energy that can be charged / discharged from lead-acid batteries will be reduced by repeated use (over time). However, it is necessary for automotive electrical components to ensure engine start-up even in such a state and to stop the engine. Must supply a lot of power. For this reason, determining the battery state such as the state of charge (SOC) or the state of health (SOH) of the lead battery is beneficial in terms of predicting the engine starting performance.

  Until now, attempts have been made to determine the SOC and SOH of a lead battery by measuring the open circuit voltage of the lead battery, measuring the internal resistance using alternating current, measuring the charging current, and discharging current. As a specific example, there has been proposed a technique for determining SOH by measuring the voltage of a lead battery when starting a starter motor (see, for example, Patent Documents 1 and 2).

  When the battery state determination device is applied to all battery state determination devices, particularly lead batteries that are installed in automobiles and start an engine, this aspect is important in order to make the device practical. For example, a technology has been proposed in which a light emitting diode (LED) is used as a status display means or an alarm means, and a battery status detection device is attached to the top surface of a lead battery or integrated with a lead battery (for example, (See Patent Document 3).

  However, in the case of a lead battery with a battery state determination device that has a battery state determination device installed in the vicinity of the lead battery or integrated with a lead battery and a battery state determination device, the device can be started up by an error after being mounted on the vehicle. In some cases, the battery state determination device cannot function.

  In order to solve this problem, a battery state determination device has been proposed that can be reliably activated after a lead battery with a battery state determination device is mounted on an automobile (see Patent Document 4). In this battery state determination device, when a lead battery with a battery state determination device is mounted on a vehicle and then the engine is started according to the normal procedure for using the lead battery, a current flows to the cell motor as a load, and at the same time the terminal voltage of the lead battery Falls, and the power supply switch of the battery state determination device connected to the terminal of the lead battery is turned on. For this reason, the user can use it without paying attention to the activation of the apparatus.

Japanese Patent No. 3673895 JP-A-2005-304173 JP 2006-47130 A WO / 2006/059511

  However, in the battery state determination device of Patent Document 4, if the lead battery with the battery state determination device is unintentionally mounted on the vehicle and the engine is started without intention by mistake, the battery state determination device In some cases, after the lead battery with a judgment device is mounted once, it may be desired to transfer it to another vehicle. In the former case, since the battery state determination device is activated, there is a problem that the device consumes electric power and the lead battery is discharged. In the latter case, after the battery state determination device is activated, the stored data is initially installed in a form in which the battery characteristics and vehicle characteristics are stored and the battery state is determined. Therefore, if this is replaced with another vehicle, the characteristics of the vehicle are generally different, so that it is considered that correct determination cannot be made. At present, in order to increase the determination accuracy, it is common to store various initial data in this way and perform determination using them. Therefore, although the battery state determination apparatus in Patent Document 4 is in a specific usage pattern, there is room for improvement.

  An object of the present invention is to provide a battery state determination device to which convenience in use is added and a lead battery for an automobile including the battery state determination device.

  In order to solve the above-described problems, a first aspect of the present invention includes a voltage measuring unit that measures a voltage of a lead battery for an automobile, and a battery state of the lead battery based on the voltage measured by the voltage measuring unit. A battery state determination device that operates with the power supplied from the lead battery, and a device activation unit that activates the device triggered by reception of an external input signal 1 for activating the device; And an initialization means for stopping the operation of the apparatus with the reception of the external input signal 2 for stopping the operation of the apparatus as a trigger after the apparatus is activated, and returning the apparatus to the initial state before the activation. And

  In this aspect, when the apparatus activation means receives the external input signal 1 for activating the apparatus, the apparatus is activated with the received external input signal 1 as a trigger. For this reason, the power consumption of the lead battery by the battery state detection apparatus until the time of apparatus start-up can be suppressed. When the apparatus is activated, the voltage of the lead battery is measured by the voltage measuring means, and the battery state of the lead battery is determined based on the voltage measured by the voltage measuring means by the state determining means. Then, when the initialization means receives the external input signal 2 for stopping the operation of the apparatus after the apparatus is activated, the initialization means stops the operation of the apparatus using the received external input signal 2 as a trigger and before the apparatus is activated. Return to the initial state. For this reason, when an apparatus is operated accidentally, an apparatus can be stopped or a lead battery can be replaced with another vehicle, and the convenience on use of a battery state determination apparatus is added.

  In this aspect, storage means for storing at least one of the voltage data measured by the voltage measurement means, the determination data determined by the state determination means, and the intermediate data generated until the battery state of the lead battery is determined by the state determination means The initialization means may stop the operation of the apparatus with the reception of the external input signal 2 as a trigger and erase the data stored in the storage means. Further, a Vst calculating means for calculating a minimum voltage value Vst at the time of starting the engine of the lead battery from the voltage measured by the voltage measuring means, and among the minimum voltage value Vst calculated by the Vst calculating means, the lead battery is in an undegraded state. Vst0 calculation means for calculating the lowest voltage value Vst0 and storage means for storing the lowest voltage value Vst0 calculated by the Vst0 calculation means, and the state determination means calculates the lowest voltage value Vst0 and Vst stored in the storage means. The health condition of the lead battery is determined based on the latest minimum voltage value Vst calculated by the means, and the initialization means stops the operation of the apparatus with the reception of the external input signal 2 as a trigger and is stored in the storage means. The minimum voltage value Vst0 may be erased. In this case, the storage means is a non-volatile memory, and further stores the minimum voltage value Vst calculated by the Vst calculation means every predetermined time, and the initialization means stores the minimum voltage value Vst0 and the minimum voltage stored in the storage means. The value Vst may be erased.

  In this embodiment, the external input signal 1 and the external input signal 2 may be voltage signals or current signals, and the external input signal 1 is a terminal voltage of the lead battery generated when a load is connected to the lead battery. The external input signal 2 may be a voltage signal or a current signal generated by a switch. Further, the time measuring means for measuring the time starting from the time when the apparatus is started by the apparatus starting means, the determination means for determining whether the time measured by the time measuring means is within a predetermined time, and the determination means determined to be within the predetermined time Sometimes, the initialization unit allows the device to be stopped and the data stored in the storage unit to be erased, and when the determination unit determines that the predetermined time is exceeded, the device is stopped by the initialization unit and stored in the storage unit. There may be provided initialization permitting / prohibiting means for prohibiting deletion of data.

  Moreover, in order to solve the said subject, the 2nd aspect of this invention is the lead battery for motor vehicles provided with the battery state determination apparatus of the 1st aspect. The lead battery of the second aspect also has the same operational effects as the first aspect.

  According to the present invention, since the apparatus is activated by the reception of the external input signal 1 for activating the apparatus by the apparatus activation means, it is possible to suppress the power consumption of the lead battery by the battery state detection apparatus until the apparatus is activated. After the apparatus is started by the initialization means, the operation of the apparatus is stopped with the reception of the external input signal 2 for stopping the operation of the apparatus as a trigger, and the apparatus returns to the initial state before the activation. When the device is operated, the device can be stopped, or the lead battery can be replaced with another vehicle, and the convenience of using the battery state determination device can be obtained.

  Hereinafter, an embodiment in which the present invention is applied to an automatic lead battery (model: 65B24R) will be described with reference to the drawings.

(Constitution)
As shown in FIG. 1, the lead battery 10 of the present embodiment has a substantially rectangular battery case 8 serving as a battery container, and a total of six electrode plate groups are accommodated in the battery case 8. Yes. For the material of the battery case 8, it is possible to select a polymer resin such as polyethylene (PE), polypropylene (PP), and acrylic butadiene styrene (ABS) that is excellent in terms of moldability, insulation, and durability. it can. In each electrode plate group, a plurality of negative electrodes and positive electrodes are laminated via a separator, and the cell voltage is set to 2.0V. Therefore, the nominal voltage of the lead battery 10 is 12V. The upper part of the battery case 8 is bonded or welded to an upper lid 9 made of a polymer resin such as PE that seals the upper opening of the battery case 8.

  The upper lid 9 is provided with two (positive and negative) output terminals 7 for supplying electric power to the outside by using the lead battery 10 as an automobile power source. In addition, the upper lid 9 accommodates (internally) a unit 1 as a battery state determination device that determines the state of charge (SOC) and the state of health (SOH) of the lead battery 10.

  As shown in FIG. 2, the unit 1 is connected to the output terminal 7 of the lead battery 10 and starts up as a device starting means for starting up the unit 1, and the power supplied from the lead battery 10 through the starting circuit 11. Power supply circuit 12 for converting the power to 5V power supply, arithmetic unit 13 including a microprocessor, an AD converter, a DA converter, a nonvolatile EEPROM, and the like, a coil-type buzzer (not shown), and a buzzer are operated. A notification unit 14 configured to include a transistor and a resistor for generating a warning sound, a switch 3 (see FIG. 1), a plurality of light emitting diodes (hereinafter referred to as LEDs), a transistor, a resistor, and the like. And an operation display unit 2 configured to display the battery state of the lead battery 10 by lighting or blinking the LED.

  As disclosed in WO / 2006/059511, the start-up circuit 11 maintains an off state when the load (cell motor) exceeding the set value is connected to the output terminal 7 of the lead battery 10. And detecting a drop in the terminal voltage of the lead battery 10 that occurs when a load is connected to the lead battery 10 and a main switch that cuts off the power supply from the lead battery 10 to the computing unit 13 (power supply circuit 12). A switch driving circuit for turning on the main switch, and a latch circuit connected to the calculation unit 13 and maintaining the main switch on as long as the binary high level signal (Von) is input from the calculation unit 13; Have.

  The start circuit 11 of the unit 1 is connected to the output terminal 7 by a connection conductor (not shown) in the upper lid 9, and the operation power source of the calculation unit 13, the notification unit 14, and the operation display unit 2 is connected to the lead battery 10 via the power circuit 12. Supplied from The LEDs constituting the operation display unit 2 are composed of four LEDs indicating the battery state (SOC, SOH) of the lead battery 10. The notification unit 14 includes a circuit board and a sub circuit board on which a buzzer is mounted. As shown in FIG. 1, the buzzer sound emitting hole 6 is provided at a position on the circuit board on which the buzzer of the sub circuit board is mounted. Is formed. The upper surface of the unit 1 is substantially flush with the upper surface of the upper lid 9.

(Operation)
Next, the operation of the unit 1 will be described focusing on the microprocessor of the arithmetic unit 13. The main operation of the microprocessor is to monitor (measure) the voltage of the lead battery 10, and when it is determined that the SOH or SOC of the lead battery 10 has fallen below a preset determination threshold, a buzzer is used after the engine is stopped. A warning is given to the user (driver), and details are as follows.

  The microprocessor takes in the digital voltage value of the lead battery 10 via the voltage measurement A / D converter every predetermined time (for example, 1 ms), and the SOC, SOH of the lead battery 10 based on the taken-in voltage value. Is determined (calculated). The microprocessor measures the temperature of the lead battery 10 via a temperature sensor such as a thermistor and an A / D converter for temperature measurement, and the temperature is converted into, for example, SOC and SOH at room temperature (25 ° C.) based on the acquired temperature value. to correct.

<Determination of SOC and SOH>
It is simple to measure the open circuit voltage (OCV) to determine the SOC. For this purpose, OCV data is obtained in advance for each SOC lead battery, a relational expression or map between the OCV and the SOC is created, and the relational expression is obtained from the OCV measured via the voltage measuring A / D converter. Or the SOC is calculated back using the map.

  SOH has a strong correlation with the internal resistance of the lead battery. A so-called DC method can be used for measuring the internal resistance of the lead battery. The direct current method is a method in which, for example, an OCV of a lead battery and a minimum voltage value Vst at the time of discharge are respectively measured, and an internal resistance is obtained from the difference therebetween. In order to determine the SOH from the internal resistance, as in the case of determining the SOC, the internal resistance data is obtained in advance for the lead battery of each SOH, and the measured lead is obtained using a relational expression or a map. The SOH may be calculated from the internal resistance of the battery. The details are disclosed in, for example, Patent Document 2 described above.

  On the other hand, the unit 1 has a function of determining the engine state based on the measured voltage of the lead battery 10. That is, the microprocessor constantly monitors (measures) the voltage of the lead battery 10, and determines the engine state of engine start, engine start, and engine stop from the measured voltage change.

<Engine start>
In general, in a vehicle having an internal combustion engine such as a gasoline engine vehicle or a diesel engine vehicle, electric power is supplied from a lead battery and a cell motor is rotated to start the engine. At this time, a large current flows, and accordingly, the voltage between the terminals of the lead battery 10 greatly drops. When the voltage drop at this time and the time change of the current are measured, a sharp peak-shaped large current flows immediately after the current starts to flow through the cell motor, and at the same time, the voltage between the terminals of the lead battery 10 shows a sharp valley-shaped voltage drop. (See FIG. 4). The lowest voltage value Vst at this time is data for determining SOH.

  The microprocessor detects the engine start by monitoring the voltage of the lead battery 10. Further, the first lowest voltage measured at the start of discharging of the lead battery 10 is calculated as the lowest voltage value Vst for determining SOH as described above.

  In this way, the microprocessor performs SOC and SOH calculations at all times or at any time. The calculated SOC and SOH values are compared with a predetermined determination threshold value every time the calculation is performed. When the SOC and SOH values are lower than the determination threshold, a preparatory operation for notification is performed in accordance with the notification timing. Since the unit 1 is accommodated in the upper lid 9 of the lead battery 10, the unit 1 is disposed at a place where the lead battery 10 is installed. Many are in the engine room or in an automobile such as a passenger compartment, and the alarm sound emitted by the buzzer is difficult to hear due to vehicle noise while driving. For this reason, the alarm sound generated by the unit 1 is generated at a timing at which the user can easily hear the alarm sound, so that the alarm sound is reliably transmitted to the user. Note that the unit 1 generates a warning sound by sending a high level signal to the gate of the transistor that operates the buzzer via the DA converter.

<Start-up circuit>
In the unit 1, the start-up circuit 11 captures the voltage drop of the discharge for driving the cell motor when starting the engine, and the supply of power to the arithmetic unit 13 (microprocessor) or the like is started via the power circuit 12. Is activated and the battery state determination operation is started.

<Unit stop by external signal>
Normally, the unit activated in this way may be used as it is. However, in this embodiment, as described above, when the unit is accidentally activated or the lead battery 10 is placed on another vehicle. When it is desired to stop the unit 1 such as when it is desired to change, the operation of the unit 1 can be stopped by an external input signal. As a preferable mode, the unit can be stopped by a signal from a switch installed at a position where the user can operate the unit. The operation at that time will be described below.

  The switch 3 is preferably a tact switch that operates by pressing a button, but other switches that operate momentarily can also be used. In order to avoid a unit stop due to an erroneous operation, it is desirable to stop the unit by continuously operating the switch 3 for a certain period of time, that is, a so-called long press. The long pressing time should be set to at least several seconds, preferably 5 seconds or more. As described above, the unit is stopped only when the button is pressed for a long time, and in the normal pressing operation for a short time, the latest determination result may be displayed by the LED, and the present invention can be used without adding a separate switch. Is feasible.

  In addition to the input signal from the switch 3, for example, a voltage signal or a current signal can be used as the external input signal for stopping the unit. In this case, a voltage or current that cannot be normally used is applied to the terminal 7. As an example, a high voltage of about 18 to 20 V is applied for about several seconds. In this case, it is preferable to separately prepare a device for generating such a voltage.

<Storage of data in nonvolatile memory>
In the unit 1, the initial data of the battery when the use of the lead battery 10 is started is stored in a nonvolatile memory such as an EEPROM. The state determination during use is performed in comparison with the initial data. By doing so, it is possible to minimize the occurrence of a determination error due to the difference in characteristics of the mounted vehicle, and it is also possible to save the use period of the lead battery 10, the environmental temperature, and other data necessary for determining the battery state.

<Initializing data when the unit is stopped>
However, when such a method is adopted, when the use of the unit 1 is started and the initial data of the lead battery 10 is already stored, the unit 1 is stopped and then the lead battery 10 is transferred to another vehicle. In case of re-loading, inconvenience occurs. This is because the unit 1 is determined based on the initial data of the lead battery 10 in the first vehicle, so that the accuracy of the determination may be greatly reduced.

  In order to avoid such a situation, in the present embodiment, the contents of the nonvolatile memory such as the EEPROM are initialized when the operation of the unit 1 is stopped by the switch operation. By doing in this way, when starting unit 1 again in the vehicle which carried out transfer, the influence used with the first vehicle can be eliminated.

  The timing of initializing the contents of the nonvolatile memory such as the EEPROM may not be when the operation of the unit 1 is stopped, but may be started again after the stop. A normal microprocessor often performs a so-called power-on reset operation that initializes an internal state at the time of startup, but the content of a nonvolatile memory such as an EEPROM may be initialized after this operation.

<Prohibition of unit stop and initialization>
In such a method of stopping the unit by operating the switch and initializing the contents of the nonvolatile memory such as the EEPROM, there may be a case where inconvenience occurs by adopting only this method. For example, this is a case in which the lead battery 10 is transferred to another vehicle after being used for a long period of time such that the lead battery 10 deteriorates in the vehicle mounted first. At this time, initial data in the replaced vehicle is acquired by the deteriorated lead battery 10, and it is conceivable that the accuracy of determination is greatly reduced.

  To avoid this situation, when a certain period of time has elapsed since the start of use of the unit 1 and the lead battery 10, the unit can be stopped by a switch operation or the like and the contents of the nonvolatile memory such as the EEPROM can be initialized. It is good to make it disappear. In a normal use mode, the lead battery 10 does not noticeably deteriorate in about one year, and can be initialized within this period. However, it is preferable to limit the period for which initialization is possible to about 3 months in which deterioration does not progress reliably. More preferably, it should be about one month. Further, in a mode in which the unit 1 itself holds data in a deteriorated state, it is possible to make the initialization impossible when the deterioration is progressing due to the deterioration state at the time of initialization.

<Notification of execution of unit stop and initialization>
When the unit is stopped by such a switch operation and the contents of the nonvolatile memory such as the EEPROM are initialized, it is preferable to notify the user by some method. If the unit 1 is equipped with a sounding element such as a buzzer as in this embodiment, the unit 1 may be sounded with an operation different from the normal operation when the unit is stopped and initialized. In addition, when a display element such as an LED is provided, an operation different from a normal display such as repeated simultaneous blinking of a plurality of LEDs may be performed.

  Next, with reference to the flowchart, with respect to the operation of the microprocessor of the unit 1 (hereinafter abbreviated as MP), the operation at the time of determining the deterioration determination SOH for determining the deterioration of the lead battery 10 is further focused. Detailed description.

  A lead battery 10 is mounted on a vehicle, and as described above, a large current flows at the time of engine start for supplying electric power from the lead battery 10 to the cell motor, and at the same time, the terminal voltage of the lead battery 10 greatly drops. The starting circuit 11 recognizes this voltage drop as the external input signal 1, and the switch driving circuit shifts the main switch from the off state to the on state. As a result, the power supply circuit 12 is connected to the lead battery 10 via the activation circuit 11, and supplies the operating power to the calculation unit 13, the notification unit 14, and the operation display unit 2. When power is supplied to the arithmetic unit 13, the MP executes a deterioration determination routine for determining deterioration of the lead battery 10.

  As shown in FIG. 3, in the deterioration determination routine, first, in step 104, an initial setting process is executed in which program data including a program stored in the ROM and a determination threshold value Vth described later is expanded in the RAM. Further, in this initial setting process, in order to keep the main switch of the starting circuit 11 in the ON state, the output of the high level signal to the latch circuit is started and the unit 1 (calculating unit 13) is started by the starting circuit 11 by the internal clock. ) Starts measuring time from the time when it starts.

  Next, in Step 106, it is determined whether or not the stop signal of the unit 1 is input by determining whether or not the switch 3 is pressed for 5 seconds or longer (the external input signal 2 is input). When a negative determination is made at step 106, the routine waits at the next step 108 until the engine is started. The MP determines the engine start based on the engine state determination described above. Therefore, when the engine is first started when the lead battery 10 is mounted on the vehicle, a series of processes from Step 104 to Step 106 are executed. When it is determined that the engine is started, in the next step 110, the voltage value stored in the RAM is referred to, which is the lowest voltage value measured at the start of the discharge of the lead battery 10, and 15 ms after the start of the discharge of the lead battery 10. The minimum voltage value measured within is calculated as the minimum voltage value Vst at engine start. Note that the MP measures the temperature of the lead battery 10 via a temperature sensor and a temperature measurement A / D converter, and corrects the minimum voltage value Vst to a voltage value at room temperature based on the acquired temperature value.

  In the next step 112, it is determined with reference to the EEPROM whether or not the minimum voltage value Vst0 at the time of starting the engine of the lead battery 10 in the non-deteriorated state has already been acquired. That is, if the minimum voltage value Vst0 is written at a predetermined address in the EEPROM, it is determined that the minimum voltage value Vst0 has already been acquired (affirmative). If it is null, the minimum voltage value Vst0 is acquired. Judge that it is not (deny).

  If the determination in step 112 is negative, it is determined in step 114 whether or not the minimum voltage value Vst calculated in step 110 satisfies the condition of the minimum voltage value Vst0 when the engine of the lead battery 10 in the non-degraded state is started. to decide. This condition is, for example, (1) within 3 months from when the lead battery 10 is attached to the automobile (beginning of use), and (2) the OCV of the lead battery 10 before starting the engine (for example, The open circuit voltage when 6 hours have elapsed after the previous engine stop) can be 12.5 V or higher. As is clear from the condition (1), the non-degraded state of the lead battery 10 does not only refer to a completely non-degraded state where the SOH is 100%, but is substantially in the initial state where the lead battery 10 is healthy. This means no deterioration.

  When a negative determination is made at step 114, the process returns to step 106 to obtain the lowest voltage value Vst0 at the time of engine start of the lead battery 10 in the non-deteriorated state, and when an affirmative determination is made, the calculation is performed at step 110 at step 116. The lowest voltage value Vst is stored (written) in the EEPROM as the lowest voltage value Vst0 when the engine of the lead battery 10 in the non-deteriorated state is started, and the routine proceeds to step 118.

  On the other hand, when the determination in step 112 is affirmative, in step 118, the lowest voltage value Vst0 at the time of starting the engine of the lead battery 10 in the non-degraded state is read from the EEPROM, and in the next step 120, the voltage difference ΔVst (= Vst0−Vst ) Is calculated. That is, the voltage difference ΔVst is obtained by subtracting the lowest voltage value at the time of the latest engine start from the lowest voltage value Vst0 stored in the EEPROM. FIG. 5 shows the transition of the terminal voltage of the lead battery at the time of starting the engine for the lead battery in the non-degraded state (initial state) and the same lead battery after deterioration. In FIG. 5, the lowest voltage value at the time of starting the engine of the lead battery in the non-degraded state is represented by Vst0, and the lowest voltage value at the time of starting the engine after deterioration is represented by Vst. As is clear from FIG. 5, as the lead battery deteriorates, the voltage difference ΔVst (= Vst0−Vst) between the lowest voltage value Vst0 in the non-degraded state and the lowest voltage value Vst after the deterioration increases.

  In the next step 122, the determination threshold value Vth is read, and in step 124, it is determined whether or not the voltage difference ΔVst is larger than the determination threshold value Vth. If the determination is negative, the deterioration has not progressed to the extent that the lead battery 10 needs to be replaced, so there is no need to issue a warning to the user (driver), and the routine returns to step 106.

  On the other hand, when an affirmative determination is made at step 124, the operation waits at the next step 126 until the engine stops. MP determines (1) When the voltage of the lead battery 10 becomes equal to or less than a certain value b after determining that the engine is being started: it is determined that the engine has been stopped from the engine starting state. For example, a voltage value of 103 to 108% of the OCV of the lead battery 10 can be used as the voltage value of b. Also, (2) after determining that the engine is being started, when the voltage of the lead battery 10 decreases at a speed equal to or higher than a certain value c and the voltage drop is equal to or more than a certain value d: It is determined that the vehicle has stopped. The voltage drop rate of c can be 1.0 to 4.0 V / s, and the voltage drop width of d can be 0.05 to 0.20 V. Further, (3) after determining that the engine is in operation, the voltage of the lead battery 10 decreases to a certain value e or less, and the voltage change width at that time is a certain constant value f with a certain time width. When the value is less than or equal to g: It is determined that the engine is stopped from the engine starting state. A voltage value of 102 to 109% of the OCV of the lead battery 10 can be used as the voltage value of e, 0.01 to 1.0 s can be used as the value of f, and 0.1 to 0.3 V can be used as the change width of the voltage of g. . MP determines that the engine has stopped when it falls under any of (1) to (3). When it is determined that the engine is stopped, in the next step 128, the fact that the lead battery 10 needs to be replaced is notified by an audible means using a buzzer and a visual means using an LED, as described below, and the process returns to step 106. .

  Since the unit 1 is accommodated in the upper lid 9 of the lead battery 10, the unit 1 is disposed at a place where the lead battery 10 is installed. Most are in an automobile such as an engine room or a passenger compartment, and an alarm sound generated by a buzzer is difficult to hear due to vehicle noise while driving. For this reason, the alarm sound generated by the unit 1 is set as follows, and the sound is generated at a timing at which the user can easily hear the alarm sound (for example, when the user goes out of the vehicle and hears a warning sound after the engine stops). The alarm sound is reliably transmitted to the user. For this reason, after determining that the engine has stopped, the unit 1 immediately outputs a high level signal to the gate of the transistor that lights the LED via the D / A converter to light the LED, and after a predetermined time has elapsed. Then, a high level signal is sent to the gate of the transistor that operates the buzzer via another D / A converter to generate a warning sound.

  At the timing of stopping the engine from the engine starting state, it is estimated that the user often performs a series of operations of getting out of the automobile, closing the door, locking the door, and leaving the automobile. Accordingly, when a warning sound is generated, if a certain time lag is provided from the timing when it is determined that the engine has stopped, there is a high possibility that an alarm will be transmitted to the user. In addition to the notification start timing, the notification continuation time by the buzzer warning sound is also an important factor of notification.

  As these specific times and times, for example, the notification start by the buzzer is preferably performed between 0 and 60 seconds after the engine is stopped. The notification duration is preferably 2 seconds or more, and it is preferable to continue notification for a maximum of several minutes. Moreover, since the optimal value of these time and time changes with the usage forms of a vehicle, what is necessary is just to be determined by each case according to the use of the lead battery 10. FIG. In addition, the lead battery 10 of this example is a thing for general passenger cars, and the alerting | reporting continuation time of the warning sound by a buzzer is set to about 30 seconds.

  According to the unit 1, in most cases, the alarm sound can be reliably transmitted to the user, but the judgment threshold value Vth for generating the alarm sound is assumed to have a margin on the assumption that several missed hearings actually occur. It is preferable to set it slightly higher.

  On the other hand, in the display of the battery state of the lead battery 10 by the LED, the LED is turned on and displayed immediately after the engine is stopped. The time is about 5 minutes in this embodiment. In the unit 1, a switch 3 is arranged on the operation display unit 2. This is because a user who hears a warning sound from the buzzer or desires to know the battery state can check the health state of the lead battery 10. That is, when there is an input from the switch 3, the battery state is displayed by an LED so that the user can arbitrarily grasp the battery state. In this example, the LED indicating that the lead battery 10 needs to be replaced is lit using a red LED in order to call the user's attention.

  Further, although omitted in FIG. 3, MP stores the latest minimum voltage value Vst of the lead battery 10 in the EEPROM every certain time (for example, 2 weeks = 336 hours). Thereby, the deterioration process of the lead battery 10 can be grasped by referring to the data in the EEPROM as necessary at a later date.

  On the other hand, if an affirmative determination is made in step 106, it is determined in step 130 whether three months have elapsed since the unit 1 (calculation unit 13) started by referring to the elapsed time of the internal clock. If the determination is negative, the lead battery 10 is considered to be substantially non-degraded, and therefore, in step 132, the data stored in the EEPROM (the minimum voltage value Vst0 and the minimum voltage value Vst stored every predetermined time) is erased. At the same time, the signal output to the latch circuit is set to the low level, and the deterioration determination routine is terminated. As a result, the main switch of the startup circuit 11 is shifted to the OFF state, and the power supply from the lead battery 10 to the arithmetic unit 13 is stopped via the power supply circuit 12. On the other hand, when the determination is affirmative, the deterioration of the lead battery 10 is considered to be progressing. Therefore, in step 134, the data stored in the EEPROM is prohibited from being erased and the unit 1 is stopped, and cannot be initialized by the LED and the buzzer. And returns to Step 108.

(Effects etc.)
Next, effects of the unit 1 will be described.

  In the unit 1, the starter circuit 11 is mounted on the lead battery 10 and first supplies power to the cell motor from the lead battery 10, thereby causing a voltage drop signal at the output terminal 7 (an external input signal 1 for starting the signal unit 1. ), The unit 1 is activated using the received external input signal 1 as a trigger. For this reason, the power consumption and deterioration promotion of the lead battery 10 by the unit 1 until the unit start-up are suppressed. When the unit 1 (calculation unit 13) is activated, the voltage of the lead battery 10 is measured, and the battery state of the lead battery is determined based on the measured voltage. Then, after the unit 1 is activated, when the user presses the switch 3 for 5 seconds or longer (when the external input signal 2 for stopping the operation of the unit 1 is received), the operation of the unit 1 is triggered by this signal. The unit 1 is stopped and the unit 1 is returned to the initial state before starting (the data stored in the EEPROM is erased). For this reason, when the unit 1 is operated by mistake, the unit 1 can be stopped, or the lead battery 10 can be replaced with another vehicle, and the convenience in use of the unit 1 is added. Moreover, since the operation of the unit 1 is stopped when the switch 3 is pressed for 5 seconds or longer (reception of the external input signal 2), the power consumption and deterioration of the lead battery 10 by the unit 1 after the unit stop is suppressed. At the same time, since the data in the EEPROM is erased, it is possible to prevent erroneous determination of the state of the lead battery 10 based on the data measured in the previous vehicle even if the data is replaced with another vehicle.

  In the above embodiment, the example is shown in which the minimum voltage value Vst0 and the minimum voltage value Vst stored every predetermined time are stored in the EEPROM. However, the present invention is not limited to this, and the determination data determined by the MP and You may make it memorize | store the intermediate data etc. which were produced | generated by determination of voltage difference (DELTA) Vst.

  Moreover, in order to promote the understanding of the embodiment, only the determination of the SOH of the lead battery 10 is illustrated in the above example. However, the SOC of the lead battery 10 is also known in the description of the embodiment and the background art section. There is no doubt that MP can make SOC determination from technology.

  Furthermore, in the above-described embodiment, an example is shown in which each unit other than the device activation unit described in the claims is realized by software. However, the present invention is not limited to this, and may be configured by hardware. Good.

  Further, in the above embodiment, the example in which the operation display unit 2 is provided with the switch 3 for stopping the unit 1 and erasing the data stored in the EEPROM has been shown, but as in WO / 2006/059511 The switch 3 may be arranged in the activation circuit 11 by providing a switch in the activation circuit 11 and adding a circuit for grasping the pressing time.

  The present invention provides a battery state determination device to which convenience in use is added and a lead battery for an automobile including the battery state determination device, and thus contributes to the manufacture and sale of the battery state determination device and the lead battery for an automobile. Therefore, it has industrial applicability.

1 is an external perspective view of a lead battery according to an embodiment to which the present invention is applicable. It is a block circuit diagram of the unit accommodated in the lead battery of the embodiment. It is a flowchart of the deterioration determination routine which the microprocessor of the calculating part of a unit performs. It is a graph which shows typically the voltage between terminals of a lead battery at the time of engine starting. It is a graph which shows the minimum voltage value at the time of engine starting of the lead battery of an undeteriorated state, and the minimum voltage value at the time of engine start of the lead battery after deterioration.

Explanation of symbols

1 unit 2 display unit 3 switch 10 lead battery (lead battery for automobile)
11 Start-up circuit (device start-up means)
13 arithmetic unit (part of voltage measuring means, state judging means, initializing means, Vst calculating means, Vst0 calculating means, timing means, judging means, initialization permitting / prohibiting means)

Claims (8)

Electric power supplied from the lead battery, comprising: voltage measuring means for measuring the voltage of the lead battery for an automobile; and state determining means for determining the battery state of the lead battery based on the voltage measured by the voltage measuring means. In the battery state determination device that operates at
Device activation means for activating the device triggered by reception of the external input signal 1 for activating the device;
An initialization means for stopping the operation of the apparatus with the reception of the external input signal 2 for stopping the operation of the apparatus as a trigger after the apparatus is activated, and returning the apparatus to the initial state before the activation;
A battery state determination device comprising:   Storage means for storing at least one of voltage data measured by the voltage measuring means, determination data determined by the state determining means, and intermediate data generated until the battery state of the lead battery is determined by the state determining means 2. The battery state determination according to claim 1, wherein the initialization unit stops the operation of the apparatus with the reception of the external input signal 2 as a trigger and erases the data stored in the storage unit. apparatus.   Vst calculating means for calculating a minimum voltage value Vst at the time of engine start of the lead battery from the voltage measured by the voltage measuring means, and no deterioration of the lead battery among the minimum voltage value Vst calculated by the Vst calculating means. Vst0 calculation means for calculating the lowest voltage value Vst0 in the state, and storage means for storing the lowest voltage value Vst0 calculated by the Vst0 calculation means, wherein the state determination means is the lowest voltage stored in the storage means The health state of the lead battery is determined based on the value Vst0 and the latest minimum voltage value Vst calculated by the Vst calculating means, and the initialization means operates the apparatus with the reception of the external input signal 2 as a trigger. The battery state determination device according to claim 1, wherein the battery voltage determination unit is configured to stop the battery voltage and erase the minimum voltage value Vst0 stored in the storage unit.   The storage means is a non-volatile memory, and further stores the minimum voltage value Vst calculated by the Vst calculation means every predetermined time, and the initialization means stores the minimum voltage value Vst0 and the minimum voltage value stored in the storage means. The battery state determination apparatus according to claim 3, wherein the voltage value Vst is erased.   5. The battery state determination device according to claim 1, wherein the external input signal 1 and the external input signal 2 are voltage signals or current signals. 6.   The external input signal 1 is a signal for lowering the terminal voltage of the lead battery generated when a load is connected to the lead battery, and the external input signal 2 is a voltage signal or a current signal by a switch. The battery state determination apparatus of any one of Claim 1 thru | or 4.   Time measuring means for measuring time starting from the time when the apparatus is started by the apparatus starting means, determination means for determining whether the time measured by the time measuring means is within a predetermined time, and the determination means determining that the time is within a predetermined time The initialization unit is allowed to stop and the data stored in the storage unit are erased. When the determination unit determines that a predetermined time is exceeded, the initialization unit stops the device and 5. The battery state determination device according to claim 2, further comprising an initialization permission / prohibition unit that prohibits erasure of data stored in the storage unit. 6.   The lead battery for motor vehicles provided with the battery state determination apparatus of any one of Claim 1 thru | or 7.

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