JPWO2006075740A1 - Quality determination method and quality determination device for lead acid battery - Google Patents

Abstract

In the method for determining the quality of a lead storage battery, the method includes a temporary charging step in which the lead storage battery is charged with a constant current, and the terminal voltage of the lead storage battery is measured within 10 seconds after charging starts with the constant current. And a determination step of determining whether or not the terminal voltage reaches a predetermined voltage, and a selection step of selecting a lead storage battery that has reached the predetermined voltage as defective.

Description

  The present invention relates to a method for determining the quality of a lead-acid battery and an apparatus for determining whether a lead-acid battery is acceptable. Moreover, this invention relates to the apparatus which charges the lead acid battery determined to be usable by the method.

  When a lead storage battery deteriorates, it cannot be used gradually. The causes include sulfation phenomenon, active material deterioration, overdischarge, and internal short circuit. The sulfation phenomenon is a phenomenon in which lead sulfate having low conductivity is deposited on the electrode plate. When this phenomenon occurs, the internal impedance of the lead storage battery increases, and the lead storage battery cannot be used. Further, when the active material is deteriorated, the active material cannot contribute to the electrochemical reaction, so that the lead-acid battery cannot be used. Moreover, if the discharge becomes too deep and overdischarge occurs, the voltage will not be sufficiently recovered even if the battery is subsequently charged, so that the lead-acid battery cannot be used. In addition, if an internal short circuit occurs between the electrode plates in the lead storage battery, the voltage of the lead storage battery decreases and the lead storage battery cannot be used.

  It is often necessary to determine whether a lead acid battery is good or defective due to such a cause. Such determination is called pass / fail determination. There are various types of determination methods. A typical example is shown below.

  The first method is a method of performing pass / fail judgment by discharging a lead storage battery at a high rate and checking whether the voltage and the discharge current are sufficiently large. Conventionally, development of a method, a device, a charger, and the like for determining pass / fail by discharging a lead storage battery at a high rate before or after charging has been advanced.

  The second method is a method in which the lead storage battery is charged with a constant current or a constant voltage, and the quality is determined based on the behavior of the charging voltage or the charging current at that time. In this case, the charging current is generally supplied for several tens of minutes to several hours, and when it is short, it takes several minutes.

  The third method is a method of judging pass / fail by examining the specific gravity and the like of the electrolytic solution. However, this method is applied only to an open type lead acid battery. This is because the sealed lead-acid battery cannot know the specific gravity of the electrolyte, which is information inside the battery. Therefore, this third method cannot be applied to all lead-acid batteries.

  Since the lead-acid battery can only be discharged after being charged, it is necessary to fully charge at least in order to perform high-rate discharge and make a pass / fail judgment. As a result, it is only when the lead storage battery to be judged is almost fully charged by chance that the first method described above can be immediately judged as good or bad, and in most other cases In this case, it was not possible to make a judgment unless the lead storage battery was actually charged. Therefore, the first method described above has a problem that it takes a considerable amount of time to obtain a result by pass / fail judgment.

  Next, even if the above-described second method is used to charge the lead-acid battery with a constant current or a constant voltage (diagnostic charge) and determine based on the behavior of the charging voltage or the charging current at that time Charging for several tens of minutes to several hours is required. If charging is not performed for this time, it is not possible to make a pass / fail judgment. Therefore, there has been a problem when the result of pass / fail judgment is required immediately. Moreover, the lead storage battery that is determined to be non-defective by the lead storage battery quality determination method that is the second method may be charged or discharged about once or twice after it is determined to be non-defective. There were also lead-acid batteries that could, but soon became unable to charge and discharge. That is, there is a problem that the determination that the product is a non-defective product by the above-described second method is not necessarily accurate.

  As a result of the research conducted by the inventors of the present application, the present inventors are able to perform charging and discharging about once or twice, but such a lead storage battery that cannot be charged and discharged immediately thereafter is common. And found that a mild sulfation phenomenon occurred. In other words, it was clarified that the lead-acid battery that caused the mild sulfation phenomenon could not be detected by the quality determination method as the second method.

  In addition, as a result of the research by the inventors of the present application, it has been overlooked that the mild sulfation phenomenon has occurred in the conventional pass / fail judgment because of the long diagnostic charging time for charging the lead storage battery. It became clear that there was. That is, when a lead storage battery having a mild sulfation phenomenon is charged, the voltage suddenly rises immediately after the charging current is passed and then drops, and thereafter, the same behavior as a good lead storage battery is exhibited. For this reason, if a conventional method is used in which a quality determination is made after performing diagnostic charging for several tens of minutes to several hours, a mild sulfation phenomenon has been overlooked.

  The present invention has been made to solve the above problems based on such knowledge. That is, an object of the present invention is to make it possible to determine the quality of a lead storage battery in a very short time. And this invention aims at providing the exact quality determination result by classifying as a defective product by detecting also the lead storage battery which has produced the mild sulfation phenomenon.

  The present invention relates to a method for determining the quality of a lead storage battery, in which the method is a temporary charging step in which the lead storage battery is charged with a constant current, and the terminal of the lead storage battery within 10 seconds after charging starts with the constant current. And a determination step in which a voltage is measured and it is determined whether or not the terminal voltage reaches a predetermined voltage, and a selection step in which a lead storage battery that has reached the predetermined voltage is selected as defective. . Further, the lead storage battery includes a single cell, and the predetermined voltage is 2.67 V or more and 3.00 V or less per single cell. Furthermore, the magnitude of the constant current in the temporary charging step is 0.03 CA or more and 0.10 CA or less.

  According to the present invention, whether the terminal voltage of the lead storage battery reaches a predetermined voltage within a short period of time, for example, about 3 seconds after the lead storage battery is charged with a constant current (temporary charging process) and this charging is started. It is determined whether or not. When the terminal voltage reaches a predetermined voltage, the lead storage battery is selected as defective. In this example, the time required for the determination and selection is about 3 seconds. Therefore, it is possible to determine the quality of the lead storage battery in a very short time compared to the conventional method.

  The “predetermined voltage” described in the claims of the present application is any one value included in a voltage range of 2.67 V or more and 3.00 V or less converted per unit cell of the lead storage battery. Currently, the lead acid battery for automobiles that is generally spread is configured by connecting six single cells in series (rated voltage: 12 V). Therefore, when converting the overall voltage of such a lead-acid battery for automobiles, “from 2.67 V to 3.00 V per single cell” means “the charging voltage of the entire lead-acid battery in which single cells are connected in series (charging) This means that the terminal voltage in the middle is 16 V or more and 18 V or less.

  And according to this invention, the lead acid battery which has produced the mild sulfation phenomenon can also be detected. When a charging current is passed through a lead storage battery in which a sulfation phenomenon occurs, the charging voltage (terminal voltage during charging) suddenly rises, but thereafter the charging voltage drops. Probably, part of lead sulfate is solubilized by charging and the internal impedance is lowered. The subsequent charging voltage behaves in the same manner as a good lead-acid battery. Therefore, such a voltage behavior is detected if it is determined whether or not the terminal voltage reaches a predetermined voltage within a short time of about 3 seconds after charging is started, as in the present invention. . And the lead storage battery which has produced the mild sulfation phenomenon is detected, and it can determine with the said lead storage battery being inferior goods.

  In this case, the terminal voltage of the lead storage battery may be measured before or at the start of charging in the temporary charging step, or may be measured after a lapse of time from the start of charging.

  After charging with constant current (temporary charging) is started, the time until the terminal voltage of the lead storage battery is measured and it is determined whether or not the terminal voltage reaches a predetermined voltage is 10 seconds or less. Any number of seconds can be used. For example, even for one second, it is possible to determine a lead storage battery according to the present invention. However, in consideration of the accuracy of the power source (device for passing current) at the technical level at the time of filing of the present application and the basic application of the present application, the time is preferably 0.5 seconds or more. On the other hand, if the time is increased to exceed 10 seconds, a lead-acid battery that is non-defective and accidentally charged can reach a predetermined voltage. If it does so, the lead storage battery which is essentially good goods will be selected as a defect by the arrival. As described above, the time is required to be 10 seconds or less.

  Moreover, the rated capacity of the lead storage battery in the present application is determined as follows. That is, a lead storage battery of the same type as that of the lead storage battery subject to pass / fail judgment, and a non-defective product, the time required for discharging until the terminal voltage of the lead storage battery becomes 1.7 V / single cell is 4 The discharge current for .75 to 5.25 hours is obtained (this discharge is a 5-hour rate discharge), and the value obtained by multiplying the value of this discharge current by 5 is the rated capacity C (unit: Ah). And “0.10 CA as the magnitude of the constant current” means that the value obtained by multiplying the magnitude of the value of the rated capacity C by 0.10 is used as the magnitude of the current. More specifically, in the 46B24L type automotive lead storage battery defined in JIS D 5301, the rated capacity C is 36 Ah, so 0.10 CA is 3.6 A.

In addition, the invention of this application can also employ | adopt the following structures.
(1) In the apparatus of the present invention, during the main charging, the terminal voltage of the lead storage battery is measured when the charging means is charging with a constant current, and it is determined whether the terminal voltage is within a predetermined voltage range. A determination means may be provided.

  According to this, since it is determined whether or not the terminal voltage of the lead storage battery is within a predetermined voltage range even when the main charge is being performed, the lead storage battery that has been overlooked when the temporary charging means is charging is determined. Defects can be found during the main charge.

(2) In the apparatus of the present invention, the determination means at the time of charging measures the terminal voltage of the lead storage battery a plurality of times or at all times, and the measured terminal voltage changes within a predetermined voltage range over time. You may make it judge whether to do.

  According to this, when the charging means is charging, it is determined whether the terminal voltage of the lead storage battery changes within a predetermined voltage range as time passes. Whether or not the change of the terminal voltage is normal is checked. Therefore, the failure of the lead storage battery that is overlooked when the temporary charging means is charging can be detected early and reliably during charging by the charging means. Note that whether or not the terminal voltage of the lead-acid battery has changed within a predetermined voltage range with the passage of time is determined by detecting how the terminal voltage changes. Therefore, the terminal voltage differential value, the terminal voltage difference value measured at different times, the terminal voltage differential value (double differential), or the difference between the terminal voltage differences can be detected. Used.

(3) In the method of the present invention, the terminal voltage of the lead storage battery is measured before charging in the temporary charging step, and if the measured terminal voltage has not reached the second predetermined voltage, You may make it provide the charge control process which does not perform charge by a charge process. In the device of the present invention, the terminal voltage of the lead storage battery is measured before the temporary charging means is charged, and if the measured terminal voltage does not reach the second predetermined voltage, charging by the temporary charging means is performed. You may make it provide the charge control means which is not performed.

  According to this, when the lead storage battery is not securely connected to the device for judging the quality, or when the positive electrode and the negative electrode are connected in reverse, the voltage of the lead storage battery cannot be measured. A situation in which charging is performed and the lead storage battery is determined to be defective can be prevented. Moreover, when the voltage of the lead storage battery correctly connected is extremely low, it can be determined that the lead storage battery is defective without actually charging. Therefore, the defect of lead acid battery is discovered in advance.

(4) In the apparatus of the present invention, during the charging by the charging means, the charging is temporarily interrupted, the lead storage battery is connected to a predetermined resistor and discharged, and the terminal voltage and discharge current of the lead storage battery are measured. In addition, a discharge determination means for determining whether or not the measured terminal voltage and discharge current are within a predetermined range may be provided.

  According to this, since it becomes possible to make the determination by discharging when the charging means is charging, a defect of the lead storage battery can be surely found.

(5) In the method of the present invention, when the determination step or the main charge determination step determines that the terminal voltage is not within the predetermined voltage range, the step of notifying the operator, the step of notifying other devices In addition, a step in which the temporary charging is automatically stopped may be included. In the device of the present invention, when the judging means or the main charging time judging means judges that the terminal voltage is not within the predetermined voltage range, means for notifying the operator, means for notifying other equipment, temporary charging Means for automatically stopping may be provided.

(6) In the method of the present invention, in the determination step, it may be determined whether or not another predetermined voltage lower than the predetermined voltage is reached. In the apparatus of the present invention, the determination means may determine whether or not another predetermined voltage lower than the predetermined voltage is reached.

  By setting this different predetermined voltage to a voltage that does not reach when the lead storage battery is in an overdischarged state or when the lead storage battery is in an internal short circuit state, the lead storage battery is brought into these states. It will be determined that it has fallen. And it becomes possible to determine the defective lead storage battery which fell into such a state.

FIG. 1 shows an embodiment of the present invention, and is a perspective view showing an external appearance of a device for judging pass / fail. FIG. 2 shows an embodiment of the present invention, and is a block diagram for explaining the function of a device for judging pass / fail. FIG. 3 shows an embodiment of the present invention, and is a flowchart for explaining the operation of the apparatus for judging pass / fail. FIG. 4 shows an embodiment of the present invention and is a flowchart for explaining details of the pre-charging process in FIG. FIG. 5 shows an embodiment of the present invention and is a time chart showing changes in charging voltage and charging current when charging a normal lead-acid battery.

Explanation of symbols

  11 is a temporary charging circuit, 12 is a main charging circuit, 12A is a constant current charging circuit, 12b is a constant voltage charging circuit, 13 is a switching circuit, 14 is a control unit, 17 is a timer, 18 is a terminal voltage measuring circuit, and 19 is a voltage. The comparison unit, 20 is a voltage difference calculation unit, and 21 is a voltage difference comparison unit.

  Hereinafter, the best embodiment of the present invention will be described with reference to FIGS.

  The apparatus in which the method of the present invention is implemented or the circuit configuration of the apparatus of the present invention will be described based on the external view of the apparatus of FIG. 1 and the functional block diagram of FIG.

(1) Outline of an apparatus in which the method of the present invention is implemented This apparatus includes a temporary charging circuit 11 and a main charging circuit 12, as shown in FIG. The charging circuit 12 includes a constant current charging circuit 12A and a constant voltage charging circuit 12b. The temporary charging circuit 11 is a charging circuit that performs constant current charging of 0.5 A at a maximum voltage of 20V. The constant current charging circuit 12A is a charging circuit that performs constant current charging of 3A at a maximum voltage of 14.5V, and the constant voltage charging circuit 12b is a charging circuit that performs constant voltage charging of 14.5V. In addition, as mentioned above, the maximum voltage is 14.5V because the lead storage battery that is subject to the pass / fail judgment by this device has six single cells and its rated voltage is 12V. is there.

  The temporary charging circuit 11, the constant current charging circuit 12A, and the constant voltage charging circuit 12b are connected to the charging terminal 1 shown in FIG.

  The controller 14 of the charger controls the charging operation of the temporary charging circuit 11, the constant current charging circuit 12A, and the constant voltage charging circuit 12b. Furthermore, the controller 14 of the charger controls the switching circuit 13 to connect any one of the temporary charging circuit 11, the constant current charging circuit 12A, and the constant voltage charging circuit 12b to the charging terminal 1, or The circuit is controlled so as not to be connected.

  A display unit 15 and an operation unit 16 are connected to the control unit 14. The display unit 15 includes the power lamp 3, the charging lamp 5, and the NG lamp 6 shown in FIG. The operation unit 16 includes the power switch 2 and the start switch 4 shown in FIG. A timer 17 is connected to the control unit 14. The timer 17 is a circuit that, when the control unit 14 designates the time measurement and instructs the start of time measurement, notifies the completion of the time measurement when the designated time elapses.

  A terminal voltage measurement circuit 18 is also connected to the charging terminal 1. The terminal voltage measuring circuit 18 is a circuit that converts a terminal voltage of a lead storage battery connected to the charging terminal 1 (this terminal voltage is also referred to as “charging voltage” if charging) into a digital signal by AD conversion. It is. The terminal voltage V converted into a digital signal by the terminal voltage measurement circuit 18 is sent to the voltage comparison unit 19 and the voltage difference calculation unit 20. The voltage difference calculation unit 20 stores the terminal voltage V sent from the terminal voltage measurement circuit 18 and calculates the difference between the terminal voltage V and the terminal voltage V sent last time to obtain a voltage difference ΔV. This voltage difference ΔV is sent to the voltage difference comparison unit 21.

  The voltage comparison unit 19 compares whether or not the terminal voltage V sent from the terminal voltage measurement circuit 18 is within the voltage range set by the control unit 14. The voltage difference comparison unit 21 compares whether or not the voltage difference ΔV sent from the voltage difference calculation unit 20 is within the voltage difference range set by the control unit 14. The comparison results of the voltage comparison unit 19 and the voltage difference comparison unit 21 are sent to the control unit 14. The voltage range and voltage difference range set by the control unit 14 include an upper limit value and a lower limit value. The upper limit value and the lower limit value may be constant values regardless of the passage of time, or may change with the passage of time, as will be described later. However, either the upper limit value or the lower limit value can be substantially omitted by setting either the upper limit value or the lower limit value to be positive or negative infinity.

  FIG. 2 is a functional block diagram for explaining the function of the charger, and does not necessarily correspond to actual hardware. For example, the temporary charging circuit 11, the main charging circuit 12, and the switching circuit 13 may be configured by switching a part of one charging circuit or switching settings. For example, when the control unit 14 is configured by a microcomputer, the voltage comparison unit 19, the voltage difference calculation unit 20, and the voltage difference comparison unit 21 can be configured as part of the program. Further, regarding the determination of the passage of time by the timer 17, the completion of time measurement may be notified by an interrupt using an interval timer, or a timer circuit that performs only time measurement may be updated from the program of the control unit 14 at any time. You may make it refer.

(2) Operation | movement of the apparatus in which the method of this invention is used Operation | movement in case a lead storage battery (rated voltage: 12V) is charged is demonstrated using the charger of the said structure. This description is based on the flowcharts of FIGS.

(2-1) Pre-charging process In this embodiment, the pre-charging process was performed before the temporary charging described in (2-2) below was started. This is because a lead-acid battery connection or a severe defect of the lead-acid battery is confirmed. However, the pre-charging process described in (2-1) is not necessarily required in the present invention.

  The operator connects the connector portion of the charging clip to the charging terminal 1, attaches the clip portion to the positive and negative terminals of the lead storage battery, and turns on the power switch 2. As a result, the power source of the charger is turned on and the control unit 14 starts operating, and the pre-charging process as shown in the first step (hereinafter referred to as “S”) 1 of the flowchart of FIG. 3 is executed.

  In the pre-charging process, as shown in FIG. 4, the power lamp 3 is turned on (S21), and the terminal voltage V (open voltage) of the connected lead storage battery is measured by the terminal voltage measuring circuit 18 (S22). Then, the voltage comparison unit 19 determines whether the terminal voltage V is equal to or higher than the predetermined voltage V1 (S23). If the predetermined voltage V1 has not been reached, the power lamp 3 is turned off (S24), the power supply of the charger is turned off (S25), and all the processes are completed. The predetermined voltage V1 is sufficiently lower than the terminal voltage V obtained when the lead storage battery has some abnormality such as an internal short circuit. Thus, the fact that the terminal voltage V has not reached the predetermined voltage V1 means that the connection of the lead storage battery by the charging clip is incomplete, or that the positive electrode and the negative electrode are reversely connected. Therefore, when the power lamp 3 is turned off, the operator is required to reconnect the lead storage battery. If the connection is still complete, it is necessary to investigate the disconnection and other causes of the charging clip.

  When the voltage comparison unit 19 determines that the terminal voltage V of the lead storage battery is equal to or higher than the predetermined voltage V1, the charger waits until the operation of the start switch 4 can be accepted and turned ON (S26). When the worker turns on the start switch 4, the terminal voltage V (open voltage) of the lead storage battery is again measured by the terminal voltage measuring circuit 18 (S27). The measurement of the terminal voltage V in S27 can also use the measurement result in S22.

  Then, the voltage comparison unit 19 determines whether or not the measured terminal voltage V is equal to or higher than the predetermined voltage V2 (S28). If the measured voltage does not reach the predetermined voltage V2, the NG lamp 6 is turned on (S29). All processing is terminated. The predetermined voltage V2 is much higher than the predetermined voltage V1, but is a predetermined voltage that is sufficiently low as the terminal voltage V of a normal and recoverable lead-acid battery. Accordingly, the fact that the terminal voltage V of the lead storage battery is not less than the predetermined voltage V1 although it is not less than the predetermined voltage V1 is considered that the lead storage battery has become a non-recoverable defect due to overdischarge or internal short circuit. Therefore, the operator can know that it is useless even if the lead storage battery is charged by turning on the NG lamp 6. Therefore, if the lead acid battery is severely defective, the charger can find this defect before starting charging. However, when it is determined in the process of S28 that the terminal voltage V of the lead storage battery is equal to or higher than the predetermined voltage V2, this pre-charging process is terminated normally and the charging process after S2 in FIG. 3 is executed.

  In the pre-charging process, if the terminal voltage V of the lead storage battery is only slightly lower than the predetermined voltage V2 even if it is equal to or higher than the predetermined voltage V1, the NG lamp 6 is lit and S2 in FIG. The subsequent charging process may be executed. In this case, since the charging is started while the NG lamp 6 is lit, the worker can know in advance that there is a high possibility that the lead storage battery is determined to be defective during the charging.

(2-2) Temporary Charging, Judgment, and Selection In temporary charging, the temporary charging circuit 11 operates, the switching circuit 13 switches to the temporary charging circuit 11, and the charging lamp 5 is lit. Then, as shown in FIG. 3, temporary charging starts (S2).

  In the charger described in the present embodiment, the charging performed by the temporary charging unit is a constant current charging of 0.5 A. Further, the charging voltage is limited to 20 V at the maximum.

  After charging by the temporary charging means was started, the terminal voltage V of the lead storage battery was measured by the terminal voltage measurement circuit 18 within 10 seconds by the timer 17 (S3). Whether or not the terminal voltage V is within the voltage range R1 is determined by the voltage comparison unit 19 (S4). This process is repeated (S5). Here, the voltage obtained by converting the upper limit value of the voltage range R1 per unit cell corresponds to the “predetermined voltage” described in the claims.

  When the terminal voltage V reaches the upper limit value of the voltage range R1 in S4, it is considered that a sulfation phenomenon has occurred in the lead storage battery. This is because when the sulfation phenomenon occurs, the internal impedance of the lead-acid battery increases. As described above, such a lead storage battery is a “bad” battery that can be used once or twice, but cannot be used immediately thereafter.

  On the other hand, if the terminal voltage V does not reach the lower limit value of the voltage range R1 in S4, it is considered that the terminal voltage V does not rise sufficiently even if the battery is actually charged due to overdischarge or internal short circuit. Such a lead acid battery is "bad".

  As described above, when the terminal voltage V is outside the range of the voltage range R1, the NG lamp 6 is turned on (S16), the charging lamp 5 is turned off, and all the processes are completed. As a result, defective lead-acid batteries can be selected with high probability as early as 10 seconds after the start switch 4 is turned on (that is, within 10 seconds from the start of charging by temporary charging). Whether or not a lead-acid battery that has been selected as defective in this way has actually become defective depends on the disassembly of the lead-acid battery (whether or not sulfation occurs) and the subsequent charge / discharge behavior. Was done by. As a result, it was revealed that the lead storage batteries selected as defective are defective due to the fact that a sulfation phenomenon actually occurs. That is, an accurate pass / fail judgment result was obtained.

  The time of 10 seconds was shortened to 5 seconds, 3 seconds, 2 seconds, and 1 second, and the pass / fail judgment was made in the same manner. Even if it did in this way, it was possible to perform the quality selection as in the case of 10 seconds. Then, whether or not the lead storage battery selected as defective actually has become defective has been verified by conducting the above-described disassembly investigation and charge / discharge behavior investigation. As a result, it was found that the lead-acid batteries selected as defective are actually defective. From the above results, it is clear that an accurate pass / fail judgment result can be obtained even if the time of 10 seconds is shortened.

  In the flowchart of FIG. 3, the terminal voltage V is always measured and determined by S3 to S5 during the temporary charging, but the measurement and the determination are made at regular intervals during the charging by the temporary charging means. Alternatively, it may be executed at a preset time. However, when the sulfation phenomenon occurs in the lead storage battery, the terminal voltage V after the start of the temporary charging suddenly increases, but a part of the lead sulfate is solubilized with the charging, and the internal impedance temporarily As a result, the terminal voltage V returns to the voltage range R1. Therefore, if the measurement and determination of the terminal voltage V is performed only once during temporary charging, there is a possibility that an abnormality due to this sulfation may be missed. Therefore, it is desirable that the measurement and determination of the terminal voltage V be performed a plurality of times or constantly.

(2-3) Main Charging The operation after 10 seconds have elapsed in S5 and selection has been made will be described.

  The constant current charging circuit 12A of the main charging circuit 12 operates, the switching circuit 13 switches to the constant current charging circuit 12A, and the constant current charging of the main charging starts (S6).

  In the charger described in the present embodiment, the constant current charging of the main charging is constant current charging by 3A, and is performed for a maximum of 6 hours by the timer 17 timing. Then, during the constant current charging of the main charging, it is determined whether or not 6 hours have elapsed from the start of the constant current charging (S7), and then the terminal voltage V of the lead storage battery is measured by the terminal voltage measuring circuit 18 ( In S8, the voltage comparison unit 19 determines whether the terminal voltage V is within the voltage range R2 (S9).

  If the terminal voltage V is within the voltage range R2, the voltage difference calculation unit 20 calculates the voltage difference ΔV of the difference between the terminal voltage V measured in the previous S8 and the terminal voltage V measured this time, and the previous terminal The current terminal voltage V is stored instead of the voltage V (S10), and the voltage difference comparison unit 21 determines whether or not the voltage difference ΔV is within the voltage difference range R3 (S11). If the voltage difference ΔV is within the voltage difference range R3, the voltage comparison unit 19 determines whether or not the terminal voltage V is 14.5V or more (S12), and S7 until the terminal voltage V becomes 14.5V or more. The process of ~ S12 is repeated. When this “14.5 V or more” is converted per single cell, it becomes “2.417 V or more”.

  In S12, the constant current charging of the main charging is limited until the terminal voltage V rises to 14.5V. If the terminal voltage V of the lead storage battery used in the present embodiment rises beyond this, the overcharge is suddenly overcharged. Because there is a fear. In addition, the constant current charge of the main charge is limited to 6 hours in the above S7 because the lead storage battery in which the terminal voltage V does not reach 14.5 V even after 6 hours have elapsed since the start of the charge. This is because it can be determined that a non-recoverable defect has occurred due to the occurrence of a minute internal short circuit or the like. Therefore, when it is determined that 6 hours have elapsed in the process of S7, the NG lamp 6 is turned on (S16), the charge lamp 5 is turned off, and all the processes are completed.

  Even when it is determined in S9 that the terminal voltage V is outside the voltage range R2, the NG lamp 6 is turned on (S16), the charging lamp 5 is turned off, and all the processes are terminated. The fact that the terminal voltage V exceeds the upper limit value of the voltage range R2 was overlooked during temporary charging, but it is considered that the internal voltage of the battery is increased due to sulfation or deterioration, and the terminal voltage V is abnormally increased. . Further, the fact that the terminal voltage V does not reach the lower limit value of the voltage range R2 is considered to be because the terminal voltage V does not rise sufficiently even if charging is performed due to the occurrence of overdischarge or internal short circuit. Accordingly, when the terminal voltage V is outside this voltage range R2, it is a failure that cannot be recovered, so the NG lamp 6 is turned on to notify the operator of the failure and the charging is stopped. And even if it starts constant current charge of this charge by this, possibility that the defect of a lead storage battery can be screened early will become high. During constant current charging of the main charging, as shown in FIG. 5, the terminal voltage V of a normal lead-acid battery rises from a voltage equal to or higher than a predetermined voltage V2 to 14.5V, so this voltage range R2 is By changing the value with the passage of time, and particularly raising the lower limit value with the passage of time, defects due to the occurrence of overdischarge or internal short circuit can be more reliably selected.

  Even when it is determined in S11 that the voltage difference ΔV is outside the voltage difference range R3, the NG lamp 6 is turned on (S16), the charging lamp 5 is turned off, and all the processes are completed. Since the voltage difference ΔV is the difference between the previous and current terminal voltages V, it indicates the rate of increase of the terminal voltage V. When this voltage difference ΔV is first calculated in S10, since the terminal voltage V measured last time is not stored, the terminal voltage V measured last in S3 may be used as the previous time. A dummy terminal voltage V that falls within the voltage difference range R3 may be prepared for the previous time, and the process of S11 may be omitted only for the first time. As shown in FIG. 5, the terminal voltage V of a normal lead-acid battery during constant current charging of the main charging increases at an initial rate and at an end of the constant current charging. Become a rate. Therefore, by examining the rate of increase of the terminal voltage V, it is possible to more accurately determine whether or not the charging is proceeding smoothly, and thereby it becomes possible to detect the failure of the lead storage battery even earlier. . That is, the fact that the voltage difference ΔV does not reach the lower limit value of the voltage difference range R3 is considered that the rate of increase of the terminal voltage V is not sufficiently high even if charging is performed due to the occurrence of an internal short circuit or the like. It can be determined that the storage battery is defective. However, since it is not particularly hindered that the rate of increase is not abnormal, it is usually possible to omit the upper limit value of the voltage difference range R3 by setting it to positive infinity.

  The voltage difference range R3 can also be changed according to the elapsed time from the start of the constant current charging of the main charging, thereby detecting that a sufficiently large increase rate is not obtained at the initial stage of charging, for example. Then, it is possible to find defects early. Even in a normal lead-acid battery, the terminal voltage V may hardly increase or may decrease slightly in the middle of charging. The lower limit value can be set to 0 or a negative value to avoid erroneous detection of defects.

  In the flowchart of FIG. 3, the terminal voltage V is always measured and determined by S8 to S11 during the constant current charge of the main charge, but these are constant times during the constant current charge of the main charge. It may be executed every time or may be executed at a preset time. In this flowchart, when it is determined whether or not the terminal voltage V of S9 is within the voltage range R2, it is always determined whether or not the voltage difference ΔV of S11 is within the voltage difference range R3. These can be performed individually and at different times and times. In particular, when the voltage difference ΔV is calculated at every time or every sampling period of AD conversion in the terminal voltage measurement circuit 18, a differential value of the terminal voltage V is obtained. Therefore, in order to eliminate the influence of such fluctuations, it is preferable to calculate the difference in the terminal voltage V measured at a certain time interval.

  If it is determined in S12 that the terminal voltage of the lead storage battery has become 14.5 V or higher, the constant current charging circuit 12A of the main charging circuit 12 is stopped and the constant voltage charging circuit 12b of the main charging circuit 12 is operated. At the same time, the switching circuit 13 is switched to the constant voltage charging circuit 12b to start constant voltage charging of the main charging (S13). The constant voltage charging of the main charging is constant voltage charging at 14.5 V, the charging current is limited to 3 A at the maximum, and is performed for a maximum of 2 hours by the timer 17 timing. During the constant voltage charging of the main charging, whether 6 hours have elapsed since the start of the constant current charging of the previous main charging (S14), and whether 2 hours have elapsed since the start of the constant voltage charging of the main charging It is determined whether or not (S15), and it waits for whichever time elapses. If it is determined in S15 that two hours have elapsed since the start of constant voltage charging, charging of the lead storage battery has been completed normally, so the charging lamp 5 is turned off and all processing is terminated. . If it is determined in S14 that 6 hours have elapsed since the start of constant current charging, charging by constant voltage charging may be insufficient, but charging is performed to limit the total charging time. Is completed normally, the charging lamp 5 is turned off and all the processes are terminated. In addition, it is determined that 6 hours have passed in S14, which means that it takes 4 hours or more for the terminal voltage V to reach 14.5V by constant current charging of the main charge, There may be a slight overdischarge or a slight short circuit. In this case, the operator may be warned that there is a minor defect in the lead-acid battery, or the lead-acid battery may be treated as defective. it can.

(2-4) Effects of the embodiment of the present invention As described above, according to the charger of the above-described embodiment in which the present invention is implemented, the lead storage battery is temporarily charged, and for a short time from the start of the charging. The voltage behavior is investigated. Therefore, conventionally overlooked lead storage batteries such as lead storage batteries that have caused the sulfation phenomenon are accurately selected as defective. In addition, whether or not the lead storage battery is defective is selected in a short time. As described above, it is possible to immediately determine whether the lead storage battery is recovered by charging or needs replacement before charging.

  In addition, even when the main charge is started, when selecting whether or not the lead storage battery is defective as needed, the lead storage battery is found defective relatively early. Therefore, it is possible to eliminate waste of charging time and take measures such as replacing the lead storage battery quickly.

  In addition, more accurate sorting is possible by making a determination based on the voltage difference ΔV as well as the terminal voltage V of the lead storage battery during the main charging.

  Furthermore, according to the quality determination method and the quality determination device of the present invention, since it is possible to find a defect with a high probability only by measuring the terminal voltage V of the lead storage battery, it is troublesome and difficult to understand, and an expensive discharge circuit. Installation is not required.

(2-5) Configuration Aspects Different from the above Embodiment In the above embodiment, a charger for charging a control valve type lead storage battery having a rated voltage of 12 V is described. However, the rated voltage, the rated capacity, etc. of the lead storage battery can be arbitrarily used, and can be similarly applied to a charger for charging lead storage batteries having a plurality of types of rated voltages. However, when the rated voltage is different, it is necessary to change the setting of the upper limit value, the lower limit value, etc. of the voltage range R1 to the voltage difference range R3.

  In the above-described embodiment, the case where the defect is selected by calculating the voltage difference ΔV during the constant current charging of the main charging is shown. However, in addition to this voltage difference ΔV or in place of this voltage difference ΔV, the difference (double differential) between the previous and current voltage differences ΔV can be calculated, and the terminal voltage V can be selected. Any calculation performed on the terminal voltage V may be used as long as it is for determining whether or not the change is within a predetermined range as time passes.

  In the above-described embodiment, a case has been described in which whether or not the predetermined time has elapsed is determined in a series of processes, for example, by referring to the time measured by the timer 17. However, when receiving a time measurement completion interrupt from the timer 17, this interrupt routine performs appropriate processing.

  By performing the processes of S3 and S4, S8 and S9, and S8, S10 and S11 in this interrupt routine, they can be executed at a fixed time interval or at a predetermined time, respectively. .

  Even during the constant current charging of the main charging, the terminal voltage V is measured, or the voltage difference ΔV is calculated, thereby selecting a defect. However, both or one of these can be omitted.

  The specific numerical values shown in the above embodiment can be arbitrarily changed according to the characteristics of the lead storage battery. For example, during constant current charging of main charging, a voltage value such as 14.5 V to be compared with the terminal voltage V in S12, 10 seconds of temporary charging, 6 hours of total time of main charging, or 2 for constant voltage charging Parameters such as time can also be changed as appropriate.

  In the above embodiment, when the lead storage battery is selected as defective, the NG lamp 6 is turned on to stop charging. However, the measure when this defect is selected is arbitrary. For example, it is possible to turn on lamps other than the NG lamp 6, display characters on the display, etc., or notify the worker by voice or the like. Furthermore, it is possible to notify a computer or the like to which this charger is connected. Further, when a failure is determined, temporary charging may be automatically stopped as in the above embodiment, or an operator may manually stop charging upon notification of failure.

  In the said embodiment, the case where defect selection was performed only by the terminal voltage V (charge voltage) of the lead storage battery was shown. However, the quality can be determined by detecting the charging current together with the terminal voltage V.

  During the constant current charging of the main charging, the charging is temporarily interrupted and discharged to thereby perform the same determination as in the conventional case. In this case, the setting operation becomes troublesome and the charger becomes expensive because a discharge circuit is provided. However, not only can a lead battery be defective at a high probability at an early stage, but also a reliable defect determination can be finally made.

  This application is based on a Japanese patent application filed on January 17, 2005 (Japanese Patent Application No. 2005-009574), the contents of which are incorporated herein by reference.

  As described above, the present invention relates to a method or apparatus for determining the quality of a lead storage battery widely used in the industry such as the automobile industry. Therefore, this method or apparatus can also be utilized industrially.

Claims (8)

In the method for determining the quality of the lead-acid battery, the method is:
Temporary charging process in which lead acid battery is charged with constant current,
A determination step in which the terminal voltage of the lead-acid battery is measured within 10 seconds after charging is started at the constant current, and it is determined whether or not the terminal voltage reaches a predetermined voltage; and There is a sorting process in which lead storage batteries that have arrived are sorted as defective. The method of claim 1, wherein
The lead storage battery includes a single cell,
The predetermined voltage is not less than 2.67V and not more than 3.00V per unit cell. The method of claim 1, wherein
The magnitude of the constant current in the temporary charging step is 0.03 CA or more and 0.10 CA or less. In the device for judging the quality of the lead-acid battery, the device is
Temporary charging means for charging the lead storage battery with a constant current;
Measuring means for measuring the terminal voltage of the lead-acid battery within 10 seconds after starting charging at the constant current, and determining whether the terminal voltage reaches a predetermined voltage; and reaching the predetermined voltage A sorting means is provided for sorting the lead-acid batteries that have been removed as defective. The apparatus according to claim 4, wherein
The lead storage battery includes a single cell,
The predetermined voltage is not less than 2.67V and not more than 3.00V per unit cell. The apparatus according to claim 4, wherein
The magnitude of the constant current in the temporary charging means is 0.03 CA or more and 0.10 CA or less. The apparatus according to any one of claims 4 to 6, wherein the apparatus further comprises:
And a main charging unit that performs main charging when the determination unit determines that the terminal voltage of the lead storage battery has not reached the predetermined voltage. The apparatus of claim 7, wherein
The main charging is constant current / constant voltage charging.

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