JP6500824B2 - Battery inspection device - Google Patents

Description

  The present specification relates to a battery inspection device (battery inspection device) for supplying power to a traveling motor. In particular, the present invention relates to a battery inspection device that outputs a remaining travel distance that is a standard for the time to replace a battery. Hereinafter, in the present specification, the “battery that supplies power to the traveling motor” may be simply referred to as “battery”.

  Batteries that supply power to the drive motor frequently repeat charging and discharging. The battery degrades while charging and discharging repeatedly. It is desirable to replace the battery if the deterioration is considerable. Since the degree of deterioration also changes depending on the use condition of the battery, the replacement time of the battery may be determined in consideration of the use condition of the battery. With regard to the battery replacement time, it is useful to know how long it takes to drive the battery replacement time after traveling a certain distance, and to provide an indication of the distance traveled until the replacement time. For example, Patent Literature 1 and Patent Literature 2 disclose techniques for calculating a travel distance which is a standard until reaching the replacement time of a battery. Hereinafter, the travel distance, which is a standard for reaching the battery replacement time from the present, is hereinafter referred to as the remaining travel distance.

JP 2012-074342 A JP, 2014-041768, A

  In the technique of Patent Document 1, the temperature of the battery during traveling is periodically measured, and the degree of deterioration and the remaining travel distance are calculated from temporal data of the temperature. Further, in the technique of Patent Document 2, the internal resistance of the battery is measured, and the remaining travel distance is calculated based on the rate of increase from the initial value of the internal resistance to the current value. Since the temperature of the battery depends not only on the deterioration of the battery but also on other factors, in the technique of Patent Document 1, the accuracy of the correlation between the remaining distance and the degree of deterioration of the battery is not high. On the other hand, since the internal resistance of the battery is directly related to the degree of deterioration of the battery, the remaining travel distance according to the technology of Patent Document 2 is excellent as a standard for the replacement time of the battery as compared with the technology of Patent Document 1. However, there is a need for a technique that can provide a more appropriate remaining distance.

  The present specification provides a technique for obtaining a more appropriate value as the remaining travel distance as a measure of battery replacement time, using the value of the internal impedance of the battery. The internal impedance has a capacitive component and a resistive component, both of which change with the deterioration of the battery. Further, the change amount of the resistance component and the change amount of the capacity component according to the deterioration of the battery may not always be the same, and may differ depending on the use condition (i.e., the running condition) of the battery. Therefore, in the technology disclosed in the present specification, the remaining life (the delay until the battery replacement time) is estimated for each of the capacity component and the resistance component, and the remaining travel distance is calculated based on the value of the smaller remaining life. Do.

  The battery inspection apparatus disclosed herein, the measuring means, the storage means, and the processor are provided. The measuring means measures the resistance component Rc1 and the capacitance component Xc1 at a predetermined first frequency of the internal impedance of the current battery, and the resistance component Rc2 and the capacitance component Xc2 at a predetermined second frequency. The storage means stores the following data. That is, the storage means stores the initial resistance change amount dRs, the initial capacity change amount dXs, the final resistance change amount dRe, and the final capacity change amount dXe. Here, the initial resistance change amount dRs is a change amount from the resistance component Rs1 at the first frequency to the resistance component Rs2 at the second frequency of the internal impedance of the battery before use. The initial capacity change amount dXs is a change amount from the capacity component Xs1 at the first frequency to the capacity component Xs2 at the second frequency of the internal impedance of the battery before use. The final resistance change amount dRe is a change amount from the resistance component Re1 at the first frequency to the resistance component Re2 at the second frequency of the internal impedance of the battery at the replacement time. The final capacity change amount dXe is a change amount from the capacity component Xe1 at the first frequency to the capacity component Xe2 at the second frequency of the internal impedance of the battery at the replacement time. These values are obtained in advance by experiments and simulations, and are stored in the storage means. The processor can perform the following processing. The processor calculates the amount of change from the measured resistance component Rc1 to the resistance component Rc2 (current resistance change amount dRc), and the change amount from the measured capacitance component Xc1 to the capacity component Xc2 (current capacity change amount dXc) Calculate The processor calculates a ratio (resistance ratio Rratio) of the difference between the final resistance change amount dRe and the current resistance change amount dRc with respect to the difference between the final resistance change amount dRe and the initial resistance change amount dRs. The processor calculates a ratio (capacity ratio Xratio) of the difference between the final capacity change amount dXe and the current capacity change amount dXc with respect to the difference between the final capacity change amount dXe and the initial capacity change amount dXs. Then, the processor sets the smaller one of the resistance ratio Rratio and the capacity ratio Xratio as the remaining life Yj, and for the travel distance SK from the start of use of the battery to the present, SK × Yj / (1.0−Yj ) Is calculated and output as the remaining travel distance.

  The replacement time of the battery means that the battery deterioration has progressed to the extent that it is better to replace it. There is a correlation between the degradation and the internal impedance of the battery. In other words, the magnitude of the internal impedance (final internal impedance) corresponding to the replacement time can be predetermined. Also known is the internal impedance (initial internal impedance) prior to battery use. Therefore, it is possible to estimate the degree of deterioration (in other words, the remaining life until replacement time) depending on where the size of the current internal impedance of the battery is located between the initial internal impedance and the final internal impedance. it can.

  On the other hand, the internal impedance includes a resistance component and a capacitance component, and the degree of change differs according to the traveling situation. Therefore, in the battery inspection device disclosed in the present specification, the current internal impedance (current internal impedance) is compared with the initial / final internal impedance for each of the resistance component and the capacitance component, and the remaining life corresponding to the degree of deterioration is calculated. Do. The resistance ratio Rratio described above corresponds to the remaining life based on the resistance component, and the capacity ratio Xratio corresponds to the remaining life based on the capacitance component. Then, the smaller one of the resistance ratio Rratio and the capacity ratio Xratio is adopted as the remaining life of the battery. Finally, the remaining travel distance (the travel distance from the current time until the replacement time is reached) is determined from the travel distance and the remaining life up to the present time. According to the above-described procedure, the battery inspection device disclosed in the present specification can output a more appropriate value as the remaining travel distance serving as an indication of replacement time.

  The magnitude of each component of the internal impedance depends on the temperature. Therefore, the technology disclosed herein employs, for each component of the internal impedance, a value change at the first frequency and a value change at the second frequency. By adopting the amount of change in the component at two frequencies, the influence of temperature can be reduced. The first frequency and the second frequency are also predetermined. The details and further improvement of the technology disclosed in the present specification will be described in the following "Forms for Carrying Out the Invention".

It is a block diagram of a battery inspection device of an example. It is a flowchart of the process which a battery test | inspection apparatus performs. It is a graph which shows an example of the Nyquist plot of the internal impedance of the battery before use and replacement | exchange time. It is a graph which shows an example of the Nyquist plot of the internal impedance of the present battery. It is a graph explaining the temperature dependence of the Nyquist plot of the internal impedance of a battery.

  A battery inspection apparatus 10 of the embodiment will be described with reference to the drawings. A block diagram of the battery inspection device 10 is shown in FIG. FIG. 1 also shows a battery 20 which is an inspection object of the battery inspection device 10. The battery 20 is a lithium ion battery mounted on an electric vehicle or a hybrid vehicle, and is a battery for supplying electric power to a traveling motor. The battery 20 is removed from the mounted vehicle and connected to the battery inspection device 10. Batteries of electric vehicles and hybrid vehicles frequently charge and discharge repeatedly. The battery degrades as it is repeatedly charged and discharged. As the deterioration progresses, the performance decreases. The manufacturer of the battery recommends replacing the battery if the deterioration has progressed to a considerable extent. The battery inspection device 10 is a device that evaluates the deterioration of the battery 20, and presents the situation regarding the replacement time of the battery 20. The battery inspection device 10 determines the degree of deterioration based on the internal impedance of the battery 20. In addition, the battery inspection device 10 presents the degree of progress of deterioration by the remaining travel distance and the remaining travel time. The remaining travel distance and the remaining travel time are numerical values that serve as an indication of how much travel should be with a vehicle equipped with the battery 20 to reach the recommended replacement time (time when deterioration has advanced enough to be replaced). The magnitude of the change in the internal impedance depends on the traveling condition up to that point. The remaining traveling distance and the remaining traveling time calculated by the battery inspection device 10 based on the internal impedance take into consideration the traveling condition up to that point, which is an appropriate indicator for the battery replacement time.

  In addition, the replacement time (the time when deterioration has advanced so as to be replaced) recommended by the battery provider may be called "battery life". In addition, the delay until the replacement time recommended by the battery provider may be called "remaining life". The remaining travel distance and the remaining travel time described above correspond to the remaining life.

  The battery inspection apparatus 10 will be described with reference to the block diagram of FIG. The battery inspection device 10 includes an AC-IR device 14, an input device 15, an output device 16, a processor 12, and a non-volatile memory 13. Specifically, the input device 15 is a keyboard or a card reader. The output device 16 is specifically a display or a printer. The AC-IR device 14 applies weak AC power between the positive electrode 20 a and the negative electrode 20 b of the battery 20 to measure the internal impedance of the battery 20. The AC-IR device 14 supplies AC power while changing the frequency, and measures the frequency characteristic of the internal impedance of the battery 20. As well known, the impedance includes a capacitive component and a resistive component, and the AC-IR device 14 can measure the capacitive component and the resistive component at each frequency of the internal impedance of the battery 20. The AC-IR device 14 and the positive electrode 20 a and the negative electrode 20 b of the battery 20 are electrically connected by a cable 14 a.

  The AC-IR device 14, the input device 15, the output device 16, the processor 12, and the non-volatile memory 13 are connected by a data bus 17 to mutually exchange data.

  The non-volatile memory 13 stores programs executed by the processor 12 and various data used for battery evaluation. The programs stored in the non-volatile memory 13 include a remaining traveling distance / remaining traveling time calculation / output program 13a. Various data used for the battery test are stored in the data area 13b. The processor 12 reads the remaining travel distance / remaining travel time calculation / output program 13a from the non-volatile memory 13 and executes the program to check the degree of deterioration of the battery 20. The processor 12 reads and uses various data from the data area 13b at the time of inspection. Various data stored in the data area 13b will be described later.

  Prior to inspecting the battery 20, the user of the battery inspection device 10 uses the input device 15 to determine the traveling distance and traveling time of the vehicle (hybrid vehicle or electric vehicle) on which the battery 20 was mounted. Input. The travel distance and travel time of the car on which the battery 20 was mounted are stored in the memory of the car. The user of the battery inspection device 10 reads the traveling distance and the traveling time from the memory of the automobile, and inputs it using the input device 15. Alternatively, in the case of a removable memory card of a memory of a car, the user of the battery test device 10 inserts the memory card into a card slot which is a type of the input device 15 of the battery test device 10 and The traveling distance and the traveling time may be input to the battery inspection device 10. The input travel distance and travel time are also stored in the data area 13 b of the non-volatile memory 13.

  The flowchart of the process which the battery test | inspection apparatus 10 performs in FIG. 2 is shown. The battery inspection device 10 first measures the internal impedance of the battery 20. As mentioned above, the AC-IR device 14 measures the internal impedance. Measurement data of the AC-IR device 14 is stored in the data area 13 b of the non-volatile memory 13 via the data bus 17.

  The battery inspection device 10 uses the AC-IR device 14 to measure the resistance component and the capacitance component of the current internal impedance of the battery 20 (S2). As mentioned above, the AC-IR unit 14 measures the internal impedance while changing the frequency of the supplied power. Here, the relationship between the frequency dependency of the resistance component and the capacitance component of the internal impedance and the deterioration of the battery will be described.

  A Nyquist plot of the internal impedance of the battery 20 is shown in FIG. The Nyquist plot is represented by a set (R, X) of a resistance component R and a capacitance component X on a coordinate axis with the resistance component R of the internal impedance taken on the abscissa and the capacitance component X of the internal impedance taken on the ordinate. It is the graph which drew the locus | trajectory (locus when changing a frequency) of internal impedance. The solid line graph of FIG. 3 shows the Nyquist plot Gs of the battery 20 before use. Arrow A in FIG. 3 indicates the moving direction of the locus of the Nyquist plot when the frequency is gradually lowered from the high frequency. The Nyquist plot of the battery 20 draws a curve in the high frequency band and becomes a straight line in the low frequency band. The point Ps1 (Rs1, Xs1) in FIG. 3 shows the internal impedance at the first frequency F1 of the battery 20 before use, and the point Ps2 (Rs2, Xs2) is the second frequency F2 of the battery 20 before use. When the internal impedance is shown. The first frequency F1 is higher than the second frequency F2. The Nyquist plot is sometimes called a Cole-Cole plot.

  As the battery 20 deteriorates, the internal impedance in the low frequency range changes. The dotted line in FIG. 4 shows the Nyquist plot Ge of the internal impedance at the time of replacement of the battery 20 recommended by the battery manufacturer (that is, the timing at which deterioration progressed as it was better to replace). In other words, the graph Ge shows the Nyquist plot of the battery 20 at the replacement time.

  The solid line portion in FIG. 4 is also part of the Nyquist plot Ge. That is, the Nyquist plot Ge at the replacement time has a shape (profile) in which the end point Ps2 of the Nyquist plot Gs before use of the battery is extended. In other words, the profile of the Nyquist plot of the internal impedance is constant regardless of the degree of deterioration at frequencies higher than the first frequency F1. Conversely, at low frequencies, the Nyquist plot profile of the battery's internal impedance changes with the degree of degradation. The first frequency F1 is selected in a frequency band in which the Nyquist plot profile does not change regardless of the degree of deterioration, and the second frequency F2 is selected in a frequency band in which the Nyquist plot profile changes in accordance with the degree of deterioration .

  The resistance component Rs1 and the capacitance component Xs1 in FIG. 3 respectively indicate the resistance component and the capacitance component at the first frequency F1 of the internal impedance of the battery 20 before use. The resistance component Rs2 and the capacitance component Xs2 respectively indicate the resistance component and the capacitance component at the second frequency F2 of the internal impedance of the battery 20 before use.

  The resistance component Re1 and the capacitance component Xe1 in FIG. 3 indicate the resistance component and the capacitance component at the first frequency F1 of the internal impedance of the battery 20 at the replacement time, respectively. The resistance component Re2 and the capacitance component Xe2 indicate the resistance component and the capacitance component at the second frequency F2 of the internal impedance of the battery 20 at the replacement time, respectively. The resistance components Rs1, Rs2, Re1, Re2, and the capacitance components Xs1, Xs2, Xe1, Xe2 are obtained in advance by experiment or simulation.

  When the resistance component Rc2 at the second frequency F2 of the battery 20 in use reaches Re2 or the capacity component Xc2 reaches Xe2, the battery 20 is said to be replaced. On the other hand, the internal impedance of the battery 20 in the low frequency range is such that the resistance component Rc changes significantly earlier than the capacitance component Xc with the passage of traveling distance (or traveling time) depending on the use condition of the battery. The component Xc changes significantly earlier than the resistance component Rc. That is, the Nyquist plot in the low frequency range changes in accordance with the traveling situation. Therefore, the battery inspection device 10 evaluates the deterioration of the battery using the larger change in the resistance component Rc2 and the capacity component Xc2 at the second frequency F2 (that is, the one in which the progress of deterioration is earlier).

  FIG. 4 shows an example Nyquist plot Gc of the internal impedance of the current battery 20. As shown in FIG. FIG. 4 is a diagram obtained by adding the Nyquist plot Gc of the current internal impedance of the battery 20 to the graph of FIG. 3 (Nyquist plot Gs, Ge). In the Nyquist plot Gc of FIG. 4, the resistance component Rc2 at the second frequency F2 of the internal impedance of the current battery 20 is a capacitance component with respect to the internal impedance Ps2 (Rs2, Xs2) at the second frequency F2 of the battery 20 before use. It has changed more than Xc2. In the example where the internal impedance of the current battery 20 is represented by the Nyquist plot Gc of FIG. 4, it is more appropriate to evaluate the deterioration of the battery 20 based on the resistance component Rc. The battery inspection device 10 acquires data corresponding to the Nyquist plot Gc of FIG. 4 using the AC-IR device 14 and stores the data in the data area 13 b.

  As described above, the profile of the Nyquist plot does not depend on the deterioration of the battery in a frequency range higher than the first frequency F1. Therefore, the internal impedance at the first frequency F1 is the same before use and at the current replacement time (the point Ps1, the point Pe1, and the point Pc1 overlap).

  In the data area 13b of the non-volatile memory 13, dRs, dXs, dRe, and dXe of FIG. 3 are stored. Here, dRs (initial resistance change amount dRs) is a change amount from the resistance component Rs1 at the first frequency F1 to the resistance component Rs2 at the second frequency F2 of the internal impedance of the battery 20 before use. dXs (initial capacity change amount dXs) is a change amount from the capacity component Xs1 at the first frequency F1 to the capacity component Xs2 at the second frequency F2 of the internal impedance of the battery 20 before use. dRe (final resistance change amount dRe) is a change amount from the resistance component Re1 at the first frequency F1 to the resistance component Re2 at the second frequency F2 of the internal impedance of the battery 20 at the replacement time. dXe (final capacity change amount dXe) is a change amount from the capacity component Xe1 at the first frequency F1 to the capacity component Xe2 at the second frequency F2 of the internal impedance of the battery 20 at the replacement time. The battery inspection device 10 compares the data with the current change amount of the battery 20 (current resistance change amount dRc, current capacity change amount dXc), and the progress degree of deterioration of the battery 20 (ie, remaining travel distance and remaining travel time Calculate).

  The battery inspection apparatus 10 uses not the absolute magnitude of the internal impedance but the amount of change from the value at the first frequency F1 to the value at the second frequency F2. This is to reduce the influence of temperature on the evaluation of deterioration, since the internal impedance changes depending on temperature. The Nyquist plot profile (graph shape) of the internal impedance of the battery does not depend on temperature. The shape of the Nyquist plot graph is constant regardless of temperature, but the position in the coordinate system with the resistance component and the capacitance component as axes changes depending on temperature. For example, FIG. 5 shows the Nyquist plot G1 of the internal impedance at a battery temperature of 10 ° C., the Nyquist plot G2 at 25 ° C., and the Nyquist plot G3 at 35 ° C. As shown in FIG. 5, the profile of the Nyquist plot of the battery 20 does not depend on temperature, but the position on the coordinate system having the resistance component and the capacitance component as axes changes according to the temperature.

  In FIGS. 3 to 5, the shape of the Nyquist plot is drawn in a simplified manner to facilitate understanding.

  Returning to FIG. 2, the description of the processing of the battery inspection device 10 will be continued. The processor 12 of the battery inspection device 10 loads and executes the remaining travel distance / remaining travel time calculation / output program 13 a stored in the non-volatile memory 13. The processor 12 performs the processing of step S2 and subsequent steps in FIG. 2 according to the remaining travel distance / remaining travel time calculation / output program 13a.

  The processor 12 accesses the data area 13b of the non-volatile memory 13 after the AC-IR device 14 measures the current internal impedance of the battery 20, and the resistance component Rc1 and the capacitance component Xc1 at the first frequency F1 of the internal impedance Also, the resistance component Rc2 and the capacitance component Xc2 at the second frequency F2 are specified (S3). Next, the processor 12 calculates the current resistance change amount dRc and the current capacity change amount dXc using the specified measurement data Rc1, Rc2, Xc1, and Xc2 (S4). The current resistance change amount dRc is a change amount from the resistance component Rc1 at the first frequency F1 to the resistance component Rc2 at the second frequency F2. The current capacity change amount dXc is a change amount from the capacity component Xc1 at the first frequency F1 to the capacity component Xc2 at the second frequency F2. Next, the processor 12 accesses the data area 13b, and reads the initial resistance change amount dRs, the initial capacity change amount dXs, the end resistance change amount dRe, and the end capacity change amount dXe (S5).

  Next, the processor 12 calculates a resistance ratio Rratio and a capacity ratio Xratio (S6). Here, the resistance ratio Rratio is the difference between the final resistance change amount dRe and the current resistance change amount dRc with respect to the difference between the final resistance change amount dRe and the initial resistance change amount dRs. The resistance ratio Rratio is determined by the equation (dRe-dRc) / (dRe-dRs). The capacity ratio X ratio is the difference between the final capacity change amount dXe and the current capacity change amount dXc with respect to the difference between the final capacity change amount dXe and the initial capacity change amount dXs. The volume ratio X ratio is determined by the equation (dXe-dXc) / (dXe-dXs).

  The resistance ratio Rratio corresponds to the distance between the final resistance component Re2 and the resistance component Rc2 at the second frequency F2 of the current battery 20 in FIG. The distance between the final resistance component Re2 and the initial resistance component Rs2 corresponds to the life of the battery 20 (the length from the start of use to the replacement time), and the resistance ratio Rratio corresponds to the remaining life. The same applies to the capacity ratio Xratio. In the equation for obtaining the resistance ratio Rratio and the capacity ratio Xratio, the change amount of the resistance component (capacitance component) at the first frequency F1 and the second frequency F2 without simply using the difference between the final resistance component Re2 and the initial resistance component Rs2. The reason for using (the initial resistance change amount dRs or the like) is to remove the influence because the position in the coordinate system of the Nyquist plot changes with the temperature of the battery 20.

  As mentioned above, the speed of change of the resistance component of the internal impedance and the speed of change of the capacitance component depend on the traveling situation. Both the resistance ratio Rratio and the capacity ratio Xratio correspond to the remaining life. In other words, the resistance ratio Rratio is the remaining life calculated based on the resistance component, and the capacity component ratio Xratio is the remaining life calculated based on the capacity component. Among the remaining life (resistance ratio Rratio) based on the resistance component and the remaining life (capacity ratio Xratio) based on the capacity component, the battery inspection device 10 adopts the smaller remaining life as the remaining life of the battery 20. That is, the processor 12 substitutes the smaller one of the resistance ratio Rratio and the capacity ratio Xratio into the remaining life Yj (S7).

  Next, the processor 12 reads the travel distance SK and travel time ST from the start of use of the battery 20 to the present from the data area 13b (S8), and the remaining travel distance ZSK and the remaining travel distance by the following (Equation 1) and (Equation 2) The traveling time ZST is calculated (S9). The travel distance SK from the start of use to the present and the travel time ST from the start of use to the present are previously input by the user of the battery inspection apparatus 10 as described above.

ZSK = SK × Yj / (1.0−YJ) (Equation 1)
ZST = ST × YJ / (1.0−YJ) (Equation 2)

  The calculated remaining travel distance ZSK and the remaining travel time ZST are presented to the user through the output device 16 such as a display (S9).

  The meanings of the above (Equation 1) and (Equation 2) will be described by exemplifying numerical values. Consider the case where the remaining life Yj is 0.2. The remaining life Yj = 0.2 means that 80% of the life up to the replacement time has already passed and the remaining 20%. For example, if the travel distance SK up to the present is 80000 km and the travel time up to the present is 8 years, substituting those values into (Equation 1), the remaining travel distance ZSK becomes 20000 km and the remaining travel time ZST becomes 2 years . That is, in this case, the battery 20 has a life of 100,000 km / 10 years, the remaining traveling distance ZSK is 20000 km, and the remaining traveling time ZST is 2 years.

  Even if the same battery and the same remaining life Yj, the traveling distance SK and the traveling time ST up to the present may be different. For example, if there are many long-distance operations using expressways, and if the operation is gentle and the load on the battery is small, then the progress of deterioration will be slower than the traveling distance / traveling time. For example, even if the same battery and the same remaining life Yj = 0.2, it is assumed that the current travel distance SK is 120000 km and the travel time ST is 12 years. In this case, the remaining running distance ZSK / the remaining running time ZST of the battery 20 is the remaining running distance ZSK = 30000 km from the equations (1) and (2), and the remaining running time ZST is 3 years.

  The battery inspection device 10 described above calculates the remaining life of each of the resistance component and the capacitance component of the internal impedance of the battery, and adopts the smaller remaining life as the remaining life of the battery 20. The time-dependent change of the resistance component and the time-dependent change of the capacity component depend on the usage of the battery, that is, the traveling condition. By adopting the smaller one of the remaining life based on the resistance component and the remaining life based on the capacity component, the battery inspection device 10 can output an appropriate remaining traveling distance / remaining traveling time as a standard for battery replacement.

  Points to note regarding the technology described in the embodiment will be described. The battery inspection device 10 of the embodiment calculates and outputs the remaining travel distance and the remaining travel time based on the internal impedance of the battery. The battery inspection device 10 may calculate and output only the remaining travel distance.

  The battery inspection device disclosed in the present specification can be applied to the remaining life calculation of lithium ion batteries, nickel metal hydride batteries, and other chemical batteries that deteriorate during repeated charging and discharging. The battery inspection device disclosed in the present specification may be applied to a battery pack including a plurality of battery packs.

  The battery inspection device 10 of the embodiment is connected to a battery removed from a car. The technology disclosed herein may be incorporated into a motor vehicle equipped with a motor and battery for traveling. In that case, the battery inspection device may present the remaining travel distance and the remaining travel time during traveling, periodically, or in response to a driver's request. The battery temperature changes while driving. The battery inspection apparatus using the change amount of the resistance component and the change amount of the capacitance component at the first frequency F1 and the second frequency F2 can preferably reduce the influence of the temperature, and therefore, is preferably incorporated in a car.

  As mentioned above, although the specific example of this invention was described in detail, these are only an illustration and do not limit a claim. The art set forth in the claims includes various variations and modifications of the specific examples illustrated above. The technical elements described in the present specification or the drawings exhibit technical usefulness singly or in various combinations, and are not limited to the combinations described in the claims at the time of application. In addition, the techniques exemplified in the present specification or the drawings can simultaneously achieve a plurality of purposes, and achieving one of the purposes itself has technical utility.

10: battery inspection device 12: processor 13: non-volatile memory 13a: output program 13b: data area 14: AC-IR device 14a: cable 15: input device 16: output device 17: data bus 20: battery

Claims (1)

A battery inspection device that calculates the remaining travel distance up to the replacement time of the battery that supplies power to the drive motor,
Measuring means for measuring a resistance component Rc1 and a capacitance component Xc1 at a predetermined first frequency of the internal impedance of the current battery and a resistance component Rc2 and a capacitance component Xc2 at a predetermined second frequency;
The amount of change from the resistance component Rs1 at the first frequency to the resistance component Rs2 at the second frequency (initial resistance change amount dRs) of the internal impedance of the battery before use, and the internal impedance of the battery before use Amount of change from the capacity component Xs1 at one frequency to the capacity component Xs2 at the second frequency (initial capacity change amount dXs) and the resistance component Re1 at the first frequency of the internal impedance of the battery at the replacement time to the second frequency Amount of change to the resistance component Re2 (final amount of change in resistance dRe) and the amount of change from the capacitive component Xe1 at the first frequency to the capacitive component Xe2 at the second frequency (final capacity) Storage means for storing the change amount dXe);
A processor,
And the processor is
The amount of change (current resistance change amount dRc) from the measured resistance component Rc1 to the resistance component Rc2 is calculated, and the amount of change (current capacity change amount dXc) from the measured capacitance component Xc1 to the capacitance component Xc2 )),
Calculating a ratio (resistance ratio Rratio) of the difference between the final resistance change amount dRe and the current resistance change amount dRc with respect to the difference between the final resistance change amount dRe and the initial resistance change amount dRs;
Calculating a ratio (capacity ratio Xratio) of the difference between the final capacity change amount dXe and the current capacity change amount dXc with respect to the difference between the final capacity change amount dXe and the initial capacity change amount dXs;
The smaller one of the resistance ratio Rratio and the capacity ratio Xratio is defined as the remaining life Yj, and SK × Yj / (1.0−Yj) with respect to the travel distance SK from the start of use of the battery to the present. Calculate and output as remaining travel distance,
Battery inspection device.

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