JP2010216995A - Method and device for decision of battery characteristics - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve detection of abnormal characteristics of a battery or a state before it reaches the abnormal characteristics as decision of the characteristics of the battery. <P>SOLUTION: The battery characteristic decision device 50 is constituted by including a switch 52; an AC signal source 54; a current detection unit 56 for detecting a battery current; and a control unit 70. The control unit 70 is constituted by including a detection waveform application module 72 for performing instruction for applying a detection AC waveform to the battery 10 to the AC signal source; a response waveform obtaining module 74 for detecting/obtaining a response current waveform relative to the detection AC waveform by the current detection unit 56; an integration processing module 76 for integrating the obtained response current waveform over a plurality of periods of the waveform; and a battery characteristic decision module 78 for determining that the battery characteristics are abnormal or normal based on the fact that a value integrated by an integration means is not zero and the fact whether an absolute value is increased with elapse of time. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a battery characteristic determination method and a battery characteristic determination apparatus, and more particularly to a battery characteristic determination method and a battery characteristic determination apparatus that determine whether a battery is in an abnormal state or a normal state.

  When the battery as the power source undergoes characteristic change, characteristic deterioration, or the like, the battery capacity is limited. Therefore, the battery characteristic is detected. For the detection of the battery characteristics, for example, a change in the internal resistance of the battery, a change in the capacity component of the battery, or the like is measured.

  For example, in Patent Document 1, as a method for detecting battery characteristics, a two-phase oscillation circuit is used to superimpose a sine wave having a predetermined frequency on a battery, and conductance G is measured in a section from 0 to π of the response current of the battery at that time. And susceptance B is calculated in the interval from 0.5π to 1.5π. And it is stated that the susceptance B reflecting the electric double layer capacitance of the battery has a correlation with the actual battery remaining capacity of the vehicle battery that repeats high-power short-time input / output.

  Patent Document 2 states that as a secondary battery evaluation method, impedances for a plurality of frequencies are obtained, and Patent Document 3 describes leakage of a DC power supply system that is electrically insulated from the body of an electric vehicle. As a high-voltage vehicle leakage detector to detect, it is described that an AC voltage signal is detected by applying a rectangular wave with a duty ratio of 50%, and leakage detection is performed. It is described that the battery voltage waveform is measured by performing charging or pulse discharging, and the battery life is determined from the voltage change per unit time. Patent Document 5 describes the deterioration diagnosis of the storage battery provided in the DC uninterruptible power supply. As a method, it is described that the internal resistance of the battery is calculated from the ripple current and the ripple voltage to determine the degree of deterioration of the storage battery.

JP 2008-107168 A JP 2004-138586 A JP 2003-125530 A JP 2007-187533 A JP 2002-101571 A

  The method of Patent Document 1 focuses on the characteristics of the electric double layer of the battery and associates it with the remaining battery capacity. According to this method, it is possible to accurately grasp the normal state of the battery, but it is impossible to detect abnormality of the battery characteristics or detection of the state before the characteristic abnormality is reached.

  An object of the present invention is to provide a battery characteristic determination method and a battery characteristic determination apparatus that enable detection of a battery characteristic abnormality or a state before a characteristic abnormality is reached.

  The battery characteristic determination method according to the present invention is acquired by applying a preset AC waveform for detection to a battery, detecting a response signal waveform of the battery when the AC waveform for detection is applied to the battery, and Battery characteristics based on an integration process that integrates the response signal waveform over multiple cycles of the waveform, and whether the value integrated by the integration process is not zero and whether the absolute value increases over time And a step of determining whether or not is abnormal or normal.

  Further, the battery characteristic determination device according to the present invention includes means for applying a preset AC waveform for detection to the battery, means for detecting a response signal waveform of the battery when the AC waveform for detection is applied to the battery, Integrating means for integrating the acquired response signal waveform over a plurality of cycles of the waveform, based on whether the value integrated by the integrating means is not zero and whether the absolute value increases with time, Means for judging whether the battery characteristics are abnormal or normal.

  In the battery characteristic determination device according to the present invention, the positive electrode and the negative electrode of the battery are used, and the detection waveform applying means applies an AC voltage waveform for detection to either the positive electrode or the negative electrode, The waveform acquisition means preferably detects and acquires the response current waveform for the electrode opposite to the electrode to which the AC waveform for detection is applied.

  Further, in the battery characteristic determination device according to the present invention, the reference electrode that is electrically neutral of the battery is used, and the detection waveform applying means is for detection between the reference electrode and either the positive electrode or the negative electrode. Preferably, an alternating current waveform is applied, and the response waveform acquisition means detects and acquires the response voltage waveform for the reference electrode.

  With the above configuration, the battery characteristics are determined by applying a preset AC waveform for detection to the battery, detecting the response signal waveform of the battery at that time, and extending the response signal waveform over a plurality of cycles of the waveform. Based on whether the integrated value is not zero and the absolute value increases with time, it is determined whether the battery characteristics are abnormal or normal.

  The present invention is based on the fact that when a sine wave of a predetermined frequency is superimposed on a battery as described in Patent Document 1, the response signal waveform of the battery may become asymmetric. Considering this reason, when the battery's oxidation reaction and reduction reaction are in a normal state, the battery response signal waveform is symmetrical and the oxidation reaction and the reduction reaction are not balanced. It was found that the response signal waveform was asymmetric in the state.

  If the response signal waveform is integrated in multiple cycles as in the above configuration, the integral value becomes zero when the waveform is symmetrical, the integral value does not become zero if the waveform is asymmetric, and the asymmetry continues or progresses. Then, the integral value increases with time. In this way, it is possible to determine whether the battery characteristics are abnormal or normal based on the integrated value of the response signal waveform.

  Here, the acquisition of a plurality of cycles of the response signal may acquire a response between the positive electrode and the negative electrode of the battery, or acquire a response between the electrically neutral reference electrode and the positive electrode. Or a response between an electrically neutral reference electrode and a negative electrode may be obtained.

  When using a positive electrode and a negative electrode of a battery, a detection AC voltage waveform is applied to either the positive electrode or the negative electrode, and a response current waveform is applied to the electrode opposite to the electrode to which the detection AC waveform is applied. Detect and get If the integral of the acquired response current waveform diverges, it can be determined that the abnormal state where the balance between the oxidation reaction and the reduction reaction is broken.

  In addition, when using a battery-neutral reference electrode, apply a detection alternating current waveform between the reference electrode and either the positive electrode or the negative electrode, and generate a response voltage waveform for the reference electrode. Detect and get. At this time, if the integral of the response voltage waveform diverges between the reference electrode and the positive electrode, it can be determined that the balance between the oxidation reaction and the reduction reaction is lost on the positive electrode side, and between the reference electrode and the negative electrode, If the integral of the response voltage waveform diverges, it can be determined that the balance between the oxidation reaction and the reduction reaction is broken on the negative electrode side. By using the reference electrode in this way, it is possible to separately determine the abnormality on the positive electrode side and the abnormality on the negative electrode side.

It is a figure explaining the structure of the battery characteristic judgment apparatus of embodiment which concerns on this invention. In embodiment which concerns on this invention, it is a figure explaining the circuit model of a battery. In embodiment which concerns on this invention, it is a figure explaining the symmetrical model of the circuit model of a battery. In embodiment which concerns on this invention, it is a figure explaining the mode of an applied signal and a response signal when a battery is a circuit model of a symmetrical model. In embodiment which concerns on this invention, it is a figure explaining the asymmetrical model of the circuit model of a battery. In embodiment which concerns on this invention, it is a figure explaining the mode of an applied signal and a response signal when a battery is a circuit model of an asymmetric model. In embodiment which concerns on this invention, it is a figure explaining the mode of the integrated waveform of an applied signal, and the integrated waveform of a response signal.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the battery to which the battery characteristic determination device is applied is described as a secondary battery that is mounted on a vehicle and included in a power supply circuit that drives a rotating electric machine. A battery that is not mounted may be used. Moreover, although the nickel hydride type high voltage battery is demonstrated as a battery, even if it is a format other than this, what is necessary is just a battery which performs an oxidation reduction reaction, and a lithium ion battery, a lead acid battery, etc. may be sufficient.

  Below, the same code | symbol is attached | subjected to the same element in all the drawings, and the overlapping description is abbreviate | omitted. In the description in the text, the symbols described before are used as necessary.

  FIG. 1 is a diagram illustrating the configuration of the battery characteristic determination device 50. Whether the battery characteristic determination device 50 is in an abnormal state or whether the battery 10 included in the power supply circuit including the inverter 8 and the like connected to the rotating electrical machine 6 mounted on the vehicle is in an abnormal state. This device has a function of determining whether or not. The battery 10 to be determined is a secondary battery that performs charging and discharging. Specifically, it is a high voltage assembled battery in which a plurality of nickel metal hydride cells are combined, and the terminal voltage thereof is, for example, about 300V.

  The battery characteristic determination device 50 includes a switch 52 that can disconnect the power supply circuit including the inverter 8 at the time of characteristic determination, an AC signal source 54 that superimposes an AC signal having a predetermined frequency on the battery 10, and the battery 10. The positive electrode 14 and the negative electrode 16 are used to detect a battery current response signal to the AC voltage signal, and the battery 10 reference electrode 12 is used to detect the battery voltage response signal to the AC current signal. Voltage detector 57, switches 58 and 59 for switching whether to detect the positive electrode side characteristic or the negative electrode side characteristic when the reference electrode 12 is used, and a control unit 70. The

  As a method for determining the characteristics of the battery 10, the positive electrode 14 and the negative electrode 16 of the battery 10 can be used, and the characteristics of the battery 10 as a whole can be determined based on the state of the response signal therebetween. Further, using the electrically neutral reference electrode 12 such as the can case of the battery 10, the characteristic determination on the positive electrode side is performed based on the state of the response signal between the reference electrode 12 and the positive electrode, or the reference Based on the state of the response signal between the electrode 12 and the positive electrode, the characteristic determination on the positive electrode side can be performed. Both methods are common in applying a detection AC waveform to the battery and evaluating the response signal waveform to the battery. Here, first, the positive electrode 14 and the negative electrode 16 of the battery 10 are used first, A description will be given of determining the characteristics of the battery 10 based on the state of the response signal. Thereafter, the characteristic determination using the reference electrode 12 will be described focusing on the differences.

  First, the battery characteristic determination based on the response signal between the positive electrode 14 and the negative electrode 16 of the battery 10 will be described.

  The AC signal source 54 is a signal generator having a function of applying a signal having a preset AC waveform for detection superimposed on the terminal voltage of the battery 10. As the AC waveform signal for detection, for example, a sine wave signal of ± 1 V, 200 Hz can be used. Of course, other voltage amplitudes and frequencies may be used. A symmetrical signal equivalent to a sine wave signal may be used. For example, the cosine wave signal can be used because it only differs in phase from the sine wave signal. The application timing of the detection AC waveform signal is set under the control of the control unit 70.

  The current detection unit 56 is a sensor circuit having a function of detecting a current waveform signal flowing through a path connecting the battery 10 and the inverter 8 as a response signal to the detection AC waveform signal. For example, current detection can be performed using an appropriate current detection resistance element. The detected data is transmitted to the control unit through an appropriate signal line.

  The control unit 70 detects the response current waveform of the battery 10 from the current detection unit 56 and obtains the response waveform from the detection waveform application module 72 that instructs the AC signal source 54 to apply the detection AC waveform to the battery 10. An acquisition module 74, an integration processing module 76 for integrating the acquired response current waveform over a plurality of cycles of the waveform, and the value integrated by the integration means is not zero, and the absolute value increases with time. A battery characteristic determination module 78 that determines whether the battery characteristic is abnormal or normal based on whether or not the battery characteristic is normal.

  The control unit 70 can be configured by an appropriate signal processing device, and for example, a computer can be used. Each function of the control unit 70 can be realized by executing software, and specifically, can be realized by executing a battery characteristic determination program. Some of these functions may be realized by hardware.

  FIG. 2 is a diagram for explaining a circuit model of the battery 10 in the configuration shown in FIG. The battery 10 is configured such that an outer can case serves as a reference electrode 12 having a neutral potential, an electrolytic solution is housed in the can case, and a positive electrode 14 and a negative electrode 16 are inserted into the electrolytic solution. Electric double layers 18 and 20 are formed in the vicinity of the positive electrode 14 and the negative electrode 16, respectively.

  As a circuit model of the battery 10, a positive electrode side electric double layer capacitor 22, an electrolyte / electron transfer resistor 26, and a negative electrode side electric double layer capacitor 24 are connected in series between the positive electrode 14 and the negative electrode 16. It can be considered that the positive electrode side reaction resistor 28 is connected in parallel to the positive electrode side electric double layer capacitor 22 and the negative electrode side reaction resistor 30 is connected in parallel to the negative electrode side electric double layer capacitor 24.

  Further, when trying to approach the actual battery 10 more than this, it is possible to insert a Warburg impedance term reflecting mass transfer in series with the positive reaction resistance 28 and the negative reaction resistance 30. In general, if the signal input to the battery is a very short time DC signal or a somewhat high AC signal, a simple CR synthesis circuit model as shown in FIG. 2 is considered sufficient. As described above, the frequency of the AC signal source is 200 Hz as described above. Therefore, the circuit model shown in FIG. 2 is used hereinafter.

  In order to determine the characteristics of a battery having such a circuit model, the following is performed. First, when the characteristic judgment is performed, the switch 52 is opened. By providing the switch 52, the battery 10 that is actually mounted on the vehicle and is operating as a power source for the rotating electrical machine 6 can be subjected to characteristic determination when necessary while being mounted on the vehicle.

  Then, the AC signal source 54 is connected to one side electrode of the battery 10, and the current detection unit 56 is connected to the other side electrode of the battery 10. Next, a detection AC waveform signal is applied from the AC signal source 54 to one electrode of the battery 10. Since the battery 10 has a terminal voltage, a signal having a detection AC waveform is superimposed on the terminal voltage. This step is executed by the function of the detection waveform applying module 72 of the control unit 70.

  In FIG. 2, the AC signal source 54 is connected to the negative electrode 16 of the battery 10, and the current detection unit 56 is connected to the positive electrode 14 of the battery 10. The current detection unit 56 may be connected to the electrode 14 and the negative electrode 56.

  In parallel with this, the detection waveform of the current detection unit 56 is acquired as a response waveform signal to the detection AC waveform signal. This process is executed by the function of the response waveform acquisition module 74 of the control unit 70. Since the acquired response waveform reflects the characteristics of the battery 10, it will be described in detail below together with the circuit model of the battery 10.

  FIG. 3 summarizes the circuit model of the battery 10 of FIG. The battery 10 between the positive electrode 14 and the negative electrode 16 can thus be modeled by the electric double layer capacity 32, the electrolyte / electron transfer resistance 34, and the reaction resistance 36. Here, the reaction resistance 36 is represented by a single resistance element, which means that the oxidation reaction and the reduction reaction in the battery 10 are balanced.

  In general, since the battery 10 should be designed so that the reaction resistance of the oxidation reaction and the reaction resistance of the reduction reaction are substantially equal, the normal battery 10 is represented by the model of FIG. Conceivable. This model can be called a symmetrical model that balances oxidation and reduction.

  FIG. 4 shows a state of the response waveform signal 82 of the battery 10 when the AC signal 80 for detection to the battery 10 is a sine wave signal and the battery 10 is in a normal reaction state and is the symmetrical model of FIG. FIG. When the battery 10 is represented by a simple CR synthesis circuit model as shown in FIG. 3, the response to the sine wave input has an amplitude attenuation due to the resistance component and a phase delay due to the capacitance component, but the waveform is a sine wave. Similarly, a vertically symmetrical waveform is maintained with respect to the time axis.

  In FIG. 5, the reaction resistance is different between the oxidation reaction and the reduction reaction, and in the equivalent circuit, the reaction resistance is represented by a diode component and a resistance component. That is, regarding the oxidation reaction, the reaction resistance is expressed on the assumption that the oxidation-side diode component dox and the oxidation-side reaction resistance Rox are connected in series. As for the reduction reaction, the reaction resistance is expressed on the assumption that the reduction side diode component dred having a polarity opposite to that of dox and the reduction side reaction resistance Rred having a value different from that of Rox are connected in series. The oxidation-side reaction resistance and the reduction-side reaction resistance are connected in parallel to represent the overall reaction resistance.

  This state indicates that the battery 10 is in an abnormal state or a state before the abnormality in a state where the oxidation reaction and the reduction reaction of the battery 10 are not balanced. This model can be called an asymmetric model with respect to the symmetric model of FIG.

  FIG. 6 shows a case where the detection AC waveform signal 80 to the battery 10 is a sine wave signal and the battery 10 has an asymmetric model in FIG. It is a figure which shows the mode of the signal 84 of the response waveform of the battery 10. When a sine wave is superimposed on the terminal voltage of the battery 10, for example, if an oxidation reaction occurs on the plus side of the sine wave, a reduction reaction occurs on the minus side. Therefore, on the plus side of the sine wave, the oxidation reaction responds correspondingly, and on the minus side, the reduction reaction responds correspondingly to become a response waveform signal 84.

  Therefore, when the reduction reaction resistance Rred is larger than the oxidation reaction resistance Rox, the minus side of the response waveform signal 84 is attenuated more than the plus side, and the minus peak value becomes smaller than the plus peak value. FIG. 6 shows such a state, and the response waveform signal 84 has an asymmetric waveform with respect to the time axis.

  As described above, in general, the battery 10 should be designed such that the reaction resistance of the oxidation reaction and the reaction resistance of the reduction reaction are substantially equal. Therefore, the oxidation reaction resistance Rox and the reduction reaction resistance The state clearly different from Rred is that the battery 10 is in an abnormal state or a state before the abnormality. This can be detected by the asymmetry of the signal 84 of the response waveform with respect to the sine wave, as shown in FIG.

  By performing an integration process on the response waveform signal, it is possible to clearly determine whether the battery 10 is in a fatal abnormal state, an abnormal state in which the battery 10 does not reach it, a state before the abnormality, or a normal state. Therefore, processing for integrating the acquired response current waveform over a plurality of periods of the waveform is performed. This step is executed by the integration processing module 76 of the control unit 70.

  FIG. 7 is a diagram for explaining that the difference is clarified by integrating the response waveform signals 82 and 84. Here, a reference integrated value waveform 90 that is a waveform after integration processing of a sine wave signal 80, a symmetric time integration value waveform 92 that is a waveform after integration processing of a response waveform signal 82 in the case of a symmetric model, and asymmetrical. An asymmetric integration value waveform 94, which is a waveform after the integration processing of the response waveform signal 84 in the model, is shown.

  As shown in FIG. 7, the reference integral value waveform 90 and the symmetrical integral value waveform 92 once pass through the integral value = 0 every cycle. On the other hand, the asymmetric integral value waveform 94 diverges in the positive direction and moves away from the integral value = 0. In the example of FIG. 7, the reduction side reaction resistance Rred is larger than the oxidation side reaction resistance Rox. On the contrary, if the oxidation side reaction resistance Rox is larger than the reduction side reaction resistance Rred, the negative side reaction resistance Rred diverges to the negative side. .

  Therefore, based on the degree of divergence, it is possible to determine whether the battery 10 is in a normal state or an abnormal state including the degree. For example, set the cycle of the integration range, determine the fatal abnormality threshold and the pre-abnormal threshold for the degree of divergence over the set cycle, and set the normal state when the integral waveform converges so that it passes through zero. If the value waveform does not converge so that it passes through zero but the divergence degree is below the pre-abnormal threshold, it is not normal but it is a state of caution before the abnormality occurs, the divergence exceeds the pre-abnormal threshold, and the fatal abnormality When the threshold is less than or equal to the threshold value, it can be assumed that the battery is in an abnormal state or a deteriorated state. This determination step is executed by the function of the battery characteristic determination module 78 of the control unit 70.

  As described above, the integration cycle is preferably performed for a cycle that is an integral multiple of the cycle of the sine wave signal or response waveform signal. The longer the integration period, the longer the determination time, but the determination accuracy improves.

  In the above, the frequency of the AC signal source 54 is 200 Hz, but any frequency between several hundred Hz and several tens Hz may be used. In order to perform more accurate measurement, signals of response waveforms are acquired at a plurality of frequencies at different frequencies, and integration processing is performed on the signals of the response waveforms at the plurality of frequencies, so that the battery 10 It is desirable to judge whether it is normal or abnormal. Further, it is preferable to change the frequency of the AC signal source 54 in accordance with the temperature condition and an assumed abnormal phenomenon or deterioration phenomenon.

  Next, the determination of the characteristics of the battery 10 using the reference electrode 12 will be described. When determining the characteristics of the battery 10 based on the response signal between the positive electrode 14 and the negative electrode 16 described above, the AC signal source 54 superimposes the AC voltage signal on the terminal voltage of the battery 10 and provides a response signal thereto. Acquired an alternating current signal. On the other hand, when the reference electrode 12 is used, the AC signal source 54 applies an AC current signal to one electrode of the battery 10 and acquires an AC voltage signal that appears in the terminal voltage of the battery 10 as a response signal.

  For this purpose, a voltage detector 57 and switches 58 and 59 are provided. The voltage detector 57 is a sensor circuit having a function of detecting a voltage waveform signal as a response to the detection alternating current waveform signal. One side of the measurement terminal of the voltage detection unit 57 is connected to the reference electrode 12, and the other side of the measurement terminal is connected to one end of each of the switches 58 and 59. The other end of the switch 58 is connected to the positive electrode 14, and the other end of the switch 59 is connected to the negative electrode 16. Control of the operation of the switches 58 and 59 is performed by the control unit 70, and the detection value of the voltage detection unit 57 is transmitted to the control unit 70 through an appropriate signal line.

  Then, as shown in FIGS. 1 and 2, the target of the voltage detected by the voltage detector 57 is switched by the switches 58 and 59. That is, when the switch 58 is turned on and the switch 59 is turned off, the voltage detector 57 detects a response voltage signal between the reference electrode 12 and the positive electrode 14. On the other hand, when the switch 58 is turned off and the switch 59 is turned on, the voltage detector 57 detects a response voltage signal between the reference electrode 12 and the negative electrode 16.

  In any case, the AC signal for detection is an AC current signal, and for example, a signal waveform that is vertically symmetrical with respect to zero current such as a sine wave is used. When such a vertically symmetrical current waveform is applied, the terminal voltage of the battery 10 responds with the battery electromotive force as the center. Therefore, when the oxidation reaction and the reduction reaction are balanced, the battery The response voltage waveform that is vertically symmetrical around the electromotive force is shown. On the other hand, when the balance between the oxidation reaction and the reduction reaction is lost, an asymmetric response voltage waveform centering on the battery electromotive force is generated, and when this is integrated for a plurality of cycles, it tends to diverge. This is the same as described above.

  Accordingly, the switch 58 is turned on, the switch 59 is turned off, and the response voltage signal between the reference electrode 12 and the positive electrode 14 is detected by the voltage detection unit 57, which is integrated by the function of the integration processing module 76, and the battery The function of the characteristic determination module 78 can be used. When the result of integration tends to diverge, it can be determined that the balance between the oxidation reaction and the reduction reaction is broken on the positive electrode 14 side and is abnormal.

  Similarly, the switch 58 is turned off, the switch 59 is turned on, the response voltage signal between the reference electrode 12 and the negative electrode 16 is detected by the voltage detection unit 57, integrated, and the result tends to diverge. In some cases, it can be determined that the negative electrode 16 side is abnormal because the balance between the oxidation reaction and the reduction reaction is lost.

  By using the reference electrode 12 in this way, regarding the abnormality of the battery 10, whether the abnormality of the portion of the positive electrode 14 or the abnormality of the negative electrode 16 is determined separately including the degree thereof. Can do.

  The battery characteristic determination method and the battery characteristic determination method according to the present invention can be used not only for a battery that performs input / output of a large amount of power for a short time, such as a battery mounted on a vehicle, but also for a battery that is gradually charged and discharged. . As a battery, it can utilize about the battery in general which has an oxidation reaction and a reduction reaction.

  6 rotating electrical machines, 8 inverters, 10 batteries, 12 reference electrodes, 14 positive electrodes, 16 negative electrodes, 18, 20 electric double layers, 22 positive electric double layer capacities, 24 negative electric double layer capacities, 26 electrolytes / electrons Movement resistance, 28 Positive reaction resistance, 30 Negative reaction resistance, 32 Electric double layer capacity, 34 Electrolytic solution / electron movement resistance, 36 Reaction resistance, 50 Battery characteristic determination device, 52, 58, 59 Switch, 54 AC signal source 56, current detection unit, 57 voltage detection unit, 70 control unit, 72 detection waveform application module, 74 response waveform acquisition module, 76 integration processing module, 78 battery characteristic determination module, 80, 82, 84 signal, 90 reference integral value Waveform, 92 Symmetric time integral value waveform, 94 Asymmetric time integral value waveform.

Claims (4)

Applying a preset AC waveform for detection to the battery;
Detecting and acquiring a response signal waveform of the battery when the AC waveform for detection is applied to the battery; and
An integration process step of integrating the acquired response signal waveform over a plurality of periods of the waveform;
A battery characteristic determination step for determining whether the battery characteristic is abnormal or normal based on whether the value integrated by the integration step is not zero and the absolute value increases with time;
A battery characteristic determination method comprising: A detection waveform applying means for applying a preset detection AC waveform to the battery;
A response waveform acquisition means for detecting and acquiring a response signal waveform of the battery when the AC waveform for detection is applied to the battery;
Integration processing means for integrating the acquired response signal waveform over a plurality of periods of the waveform;
Battery characteristic determining means for determining whether the battery characteristic is abnormal or normal based on whether the value integrated by the integrating means is not zero and the absolute value increases with time;
A battery characteristic judging device comprising: In the battery characteristic judging device according to claim 2,
Using the positive electrode and negative electrode of the battery,
The detection waveform applying means applies an AC voltage waveform for detection to either the positive electrode or the negative electrode,
The response waveform acquisition means detects and acquires a response current waveform for an electrode opposite to the electrode to which the AC waveform for detection is applied. In the battery characteristic judging device according to claim 2,
Using a reference electrode that is electrically neutral in the battery,
The detection waveform applying means applies a detection alternating current waveform between the reference electrode and either the positive electrode or the negative electrode,
The response waveform acquisition means detects and acquires a response voltage waveform for the reference electrode.

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