JP4884435B2 - Storage battery state determination device and storage battery state determination method - Google Patents

Description

  The present invention relates to a storage battery state determination device and a storage battery state determination method for determining a charge state of a storage battery and a deterioration state of the storage battery by measuring a direct current resistance of a storage battery, for example, a lead storage battery.

  Conventionally, as a method for easily detecting a deterioration state of a storage battery in a short time, a method of estimating from a measured value of an alternating current impedance between both terminals of the storage battery has been proposed (for example, see Patent Document 1). This estimation method utilizes the fact that the AC impedance of the storage battery has a correlation with the deterioration state.

  In Patent Document 1, when the storage battery is in a polarized state such as float charge, there is a problem that the battery is affected by polarization during impedance measurement. In actuality, in the storage battery state immediately after charging of the storage battery or immediately after the discharge, even if the frequency of the AC power supply is 1 kHz, there is a case where it is affected by polarization.

  On the other hand, a method for detecting the capacity of a storage battery has been proposed for examining the deterioration characteristics of the storage battery (for example, see Patent Document 2).

In Patent Document 2, as described in paragraph 0018 of the specification, it is assumed that a discharge state in which a current of a certain level or more flows is stable for a certain period of time, and in paragraph 0024, a charge duration with a current of 0.5 C or more is 5 It is determined whether or not it has become more than a second. Therefore, Patent Document 2 only shows polarization stabilization for a DC state. For example, Patent Literature 3 describes the same concept as Patent Literature 2.
JP-A-5-281310 Paragraphs 0018 and 0024 of JP-A-2003-7353 JP 7-244135 A

  As described above, there is no DC resistance measurement method by constant current instantaneous discharge that reliably avoids the polarization history of the storage battery in a short time, and the state of charge (SOC) in the state with the polarization history is not determined.

  Therefore, the present invention has been made to solve such a problem, and it is possible to measure a stable DC resistance even in an environment where a polarization history exists, and as a result, a storage battery in which the state determination of the storage battery is ensured. It is an object of the present invention to provide a state determination apparatus and a state determination method for a storage battery.

In order to achieve the above object, the invention corresponding to claim 1 comprises: instantaneous discharge means for supplying an instantaneous discharge cycle by supplying a constant direct current to the storage battery after the storage battery is left charged for a predetermined time; After the discharge means is operated, a first DC voltage measurement means for measuring the DC voltage left after the end of the instantaneous discharge cycle, and a constant current with respect to the storage battery after the first DC voltage measurement means is operated. a second DC voltage measuring means for measuring the minimum voltage at that time subjected to instantaneous discharge, constant direct current was flowed to the voltage difference and the electric storage battery of both measured in the first and second DC voltage measuring means A storage battery state determination apparatus comprising: a calculation unit that calculates a direct current resistance of the storage battery based on a current; and a determination unit that determines a state of the storage battery based on a calculation result of the calculation unit.

In order to achieve the above object, the invention corresponding to claim 2 comprises: an instantaneous discharge means for supplying an instantaneous discharge cycle by supplying a constant direct current to the storage battery after the storage battery is left charged for a predetermined time; After the discharge means is operated, a first DC voltage measurement means for measuring the DC voltage left after the end of the instantaneous discharge cycle, and a constant current with respect to the storage battery after the first DC voltage measurement means is operated. a second DC voltage measuring means for measuring the minimum voltage at that time subjected to instantaneous discharge, constant direct current was flowed to the voltage difference and the electric storage battery of both measured in the first and second DC voltage measuring means Utilizing the calculation means for calculating the direct current resistance of the storage battery based on the current, and setting the DC resistance by the calculation means, and providing a standing time for a certain period of time, and the transient voltage during this period depends on the state of charge of the storage battery And discriminating means for discriminating the charged state of the battery Te is state detecting apparatus of a storage battery provided with the.

To achieve the aforementioned object, the present invention corresponding to claim 3, after the battery has been predetermined time charging stand, giving instantaneous discharge cycle a constant current DC to the battery, the instantaneous discharge cycle after the end measuring the left DC voltage of, after measuring the DC voltage, the minimum voltage at that time a constant current instantaneous discharge to the battery is measured, the difference as well as the battery of the DC voltage and the minimum voltage This is a storage battery state determination method for determining the state of a storage battery by measuring the direct current resistance of the storage battery based on a constant DC current passed.

To achieve the aforementioned object, the present invention corresponding to claim 4, after the storage battery is a predetermined time charging stand, giving instantaneous discharge cycle a constant current DC to the battery, the instantaneous discharge cycle after the end measuring the left DC voltage of, after measuring the DC voltage, the minimum voltage at that time a constant current instantaneous discharge to the battery is measured, the difference as well as the battery of the DC voltage and the minimum voltage The storage battery is measured by measuring the direct current resistance of the storage battery on the basis of a constant direct current, and after the measurement of the direct current resistance, the storage battery is allowed to stand for a fixed time, and the transient voltage during this period depends on the state of charge of the storage battery. This is a storage battery state determination method for determining the state of charge.

  According to the present invention described above, there is provided a storage battery state determination device and a storage battery state determination method that enable stable DC resistance measurement even in an environment where polarization history exists, and as a result, the state determination of the storage battery is ensured. Can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, referring to FIG. 1 for an overview of an object to which the storage battery state determination device or the storage battery state determination method of the present invention is applied, for example, an auxiliary storage battery for automobiles. I will explain. In FIG. 1, an alternator 1 is connected to both a main storage battery 2 composed of a main storage battery body 2a and a control circuit 2b, and an auxiliary storage battery 3 which is a spare storage battery composed of an auxiliary storage battery body 3a and a control circuit 3b. When 2 is normal, the main storage battery 2 is used for controlling lamps, stereos, and engines and brakes, which are loads 5, via a switching circuit 4.

  Since the auxiliary storage battery 3 cannot be used due to a failure of the main storage battery 2, the connection between the load 5 and the auxiliary storage battery 3 is utilized by the switching circuit 4, so that the auxiliary storage battery 3 that is always charged at a constant voltage is always in the state. Since it is necessary to make it a favorable state, it is comprised so that the state of the auxiliary storage battery 3 can be grasped | ascertained by the storage battery state determination device 7 mentioned later.

  The storage battery state determination unit 7 includes the following means. Instantaneous discharge means, first DC voltage measurement means, second DC voltage measurement means, calculation means, and discrimination means are provided.

The instantaneous discharge means is, for example, a switch such as a switch electrically connected in series to the auxiliary storage battery 3 that repeats the instantaneous discharge a plurality of times, and is a constant DC current to the auxiliary storage battery 3 in order to erase the polarization history. I is applied to give an instantaneous discharge cycle. The first DC voltage measuring means measures the DC voltage V1 left after the instantaneous discharge means is operated and after the instantaneous discharge cycle is completed. The second DC voltage measuring means measures the minimum voltage V2 when the first DC voltage measuring means performs a constant current instantaneous discharge to the auxiliary storage battery 3 after the operation. The computing means computes the DC resistance of the auxiliary storage battery 3 based on the voltage difference between the two measured by the first and second DC voltage measuring means and the constant DC current passed through the auxiliary storage battery 3. The discrimination means discriminates the state of the auxiliary storage battery 3 based on the calculation result of the calculation means.

  As shown in FIG. 2, the storage battery state determination unit 7 does not calculate the DC resistance for the first few cycles in the instantaneous constant current discharge measurement, and does not calculate the polarization history [processing for the purpose of aligning the polarization history] S10. ], After performing the instantaneous constant current discharge a plurality of times, a standing time (S4) is provided, and the SOC is detected using the transient voltage at this time (S11).

  Specifically, for the auxiliary storage battery 3 that is constantly charged at a constant voltage, a determination test based on instantaneous constant current discharge is performed in order to grasp the deterioration state and the SOC state at regular intervals. At this time, in order to output a stable measurement value, constant voltage charging is temporarily stopped at the time of determination, and a constant current instantaneous discharge is performed a plurality of times after a certain standing time.

  2A shows a voltage waveform of the auxiliary storage battery 3, and FIG. 2B is a time chart for explaining the operation of the storage battery state determination unit 7 or the state determination method of the auxiliary storage battery 3. FIG.

  As shown in FIG. 2, after charging S1 of the auxiliary storage battery 3 is stopped and left for a predetermined time S2, the DC resistance is not calculated for several cycles, and the polarization history erasing process (a process for making the polarization history constant) is performed. Perform (S10). The number of cycles required at this time depends on the discharge current value or the discharge time. The number of cycles required at this time needs to obtain the optimum conditions for the target storage battery and the intended use in advance through experiments.

  In general, when calculating the DC resistance by constant current instantaneous discharge, the fluctuation voltage ΔV is calculated from the stable open circuit voltage V0 and the minimum voltage Vmim before the test, and the following formula ( Calculate DC resistance according to 1).

R0 = (V0−Vmim) / I (1)
However, in a storage battery state having a polarization history, it is necessary to leave for a long time in order to obtain a stable open circuit voltage. Therefore, the polarization history erasure is performed to perform a constant constant current instantaneous discharge cycle satisfying the above conditions (S10), the open circuit voltage after the end of the constant cycle is measured as V1, and the subsequent constant current instantaneous discharge is performed. The minimum voltage V2 is measured. And DC resistance R1 is calculated by Formula (2).

R1 = (V1-V2) / I (2)
By these processes, a stable direct current resistance value can be output even for a storage battery having a polarization history that is not in a steady state.

  Since the DC resistance value varies depending on the temperature, it is necessary to simultaneously measure the storage battery temperature and correct the DC resistance measurement value.

  The DC resistance calculated in this way can be used as a reference indicating the deterioration state of the storage battery. For the purpose of determining the SOC, a standing time (several seconds) is provided after the instantaneous discharge, and the SOC is determined using the transient voltage at this time. After instantaneous discharge, since the polarization history of the storage battery can be made constant, the transient voltage can be measured in a stable state for each measurement.

  In this embodiment, paying attention to the fact that the transient voltage after a certain time has elapsed is proportional to the SOC, the SOC is determined from the transient voltage after the certain time has elapsed. In this case, the relationship between the transient voltage at 0.5 sec after the instantaneous discharge and the state of charge SOC is almost the same as in FIG.

  Since this transient voltage varies depending on the storage battery temperature and the deterioration state of the storage battery, it is necessary to perform temperature correction and deterioration correction.

  According to the embodiment of the present invention described above, the direct current resistance can be measured in a short time as compared with the above-mentioned Patent Document 2, and there is less variation than the measurement result of the direct current resistance by the conventional method. Specifically, the horizontal axis impedance in FIG. 4 is almost the same as that obtained by replacing the DC resistance.

The block for demonstrating embodiment of the state determination apparatus of the storage battery of this invention. The figure for demonstrating operation | movement of embodiment of FIG. 1, and embodiment of the state determination method of the storage battery of this invention. The figure which shows the relationship between SOC and open circuit voltage for demonstrating the effect of FIG.1 and FIG.2. The figure which shows the relationship between the impedance and SOH for demonstrating the effect of FIG.1 and FIG.2 by comparing with the conventional method.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Alternator, 2a ... Main storage battery main body, 2b ... Control circuit, 2 ... Main storage battery, 3a ... Auxiliary storage battery main body, 3b ... Control circuit, 3 ... Auxiliary storage battery, 4 ... Switching circuit, 5 ... Load, 7 ... Storage battery state determination vessel.

Claims (4)

After the storage battery is a predetermined time charging stand, the instantaneous discharge means for providing the instantaneous discharge cycle a constant current DC to the battery,
A first DC voltage measuring means for measuring a DC voltage left after the instantaneous discharge cycle is operated, after the end of the instantaneous discharge cycle;
Second DC voltage measuring means for performing a constant current instantaneous discharge on the storage battery after the first DC voltage measuring means is operated and measuring a minimum voltage at that time;
A calculating means for calculating a DC resistance of the battery based on the first and constant current of the second DC voltage direct current flowed to the voltage difference and the power storage pond measured both by the measuring means,
Discriminating means for discriminating the state of the storage battery based on the calculation result of the calculating means;
The state determination apparatus of the storage battery provided with. After the storage battery is a predetermined time charging stand, the instantaneous discharge means for providing the instantaneous discharge cycle a constant current DC to the battery,
A first DC voltage measuring means for measuring a DC voltage left after the instantaneous discharge cycle is operated, after the end of the instantaneous discharge cycle;
Second DC voltage measuring means for performing a constant current instantaneous discharge on the storage battery after the first DC voltage measuring means is operated and measuring a minimum voltage at that time;
A calculating means for calculating a DC resistance of the battery based on the first and constant current of the second DC voltage direct current flowed to the voltage difference and the power storage pond measured both by the measuring means,
After calculating the direct current resistance by the calculation means, a determination means for determining a charge state of the storage battery by using a fact that a standing time is provided for a certain period of time and a transient voltage during this period depends on the charge state of the storage battery;
The state determination apparatus of the storage battery provided with. After the storage battery is a predetermined time charging stand, giving instantaneous discharge cycle a constant current DC to the battery, to measure the left DC voltage after the instantaneous discharge cycle ended, after measuring the DC voltage , the minimum voltage at that time a constant current instantaneous discharge to the battery is measured, the DC resistance of the battery was measured based on the DC constant current supplied to the differential and the battery of the DC voltage and the minimum voltage A storage battery state determination method for determining a storage battery state. After the storage battery is a predetermined time charging stand, giving instantaneous discharge cycle a constant current DC to the battery, to measure the left DC voltage after the instantaneous discharge cycle ended, after measuring the DC voltage , the minimum voltage at that time a constant current instantaneous discharge to the battery is measured, the DC resistance of the battery was measured based on the DC constant current supplied to the differential and the battery of the DC voltage and the minimum voltage A method for determining a state of a storage battery, wherein after the measurement of the DC resistance, a standing time is provided for a certain period of time, and the state of charge of the storage battery is determined by utilizing the transient voltage depending on the state of charge of the storage battery.

Images