JP2020165908A - Battery characteristic detector - Google Patents

Abstract

To enable the current characteristic value of a battery to be estimated with good accuracy, even when there is a large deviation between the battery temperature at previous degradation determination time and the current battery temperature.SOLUTION: Hereunder, a characteristic value D corresponding to a temperature T which a battery the degradation level of which is equivalent to a prescribed first reference point of time tb has, is defined as a first reference value Db, and a characteristic value D corresponding to a temperature T which a battery the degradation level of which is equivalent to a second reference point of time te following the first reference point of time tb has, is defined as a second reference value De. A detection unit detects degradation information α that indicates the degradation state of the battery, on the basis of a characteristic value D1 at a prescribed first point of time t1 and both reference values Db, De at a battery temperature T1 at the first point of time t1. An estimation unit estimates a characteristic value D2 at a second point of time t2 on the basis of the detected degradation information α and the temperature T2 of a battery 10 at a prescribed second point of time t2 following the first point of time t1.SELECTED DRAWING: Figure 3

Description

The present invention relates to a battery characteristic detection device that detects a characteristic value of a battery.

Some battery control devices mounted on a vehicle detect the internal resistance value of the battery and control the use of the battery based on the resistance value. Then, as a document showing such a technique, there is the following Patent Document 1.

JP-A-2018-148720

In order to measure the resistance value of a battery with high accuracy, it is necessary to pass a large amount of current to the internal resistance by charging and discharging the battery. Therefore, depending on the battery, it may not be possible to grasp the resistance value immediately after the vehicle is started. If the resistance value cannot be grasped, the use of the battery cannot be controlled based on the resistance value. Therefore, the period during which the battery can be used is reduced, leading to a decrease in fuel consumption.

On the other hand, the resistance value of the battery during the previous startup period cannot be saved and the previous resistance value cannot be inherited even after the current startup. This is because the resistance value of the battery is temperature-dependent, so if the temperature of the battery during the previous startup period and the temperature of the battery at the time of the current startup are different, the resistance value of the battery will also be different.

The following method can be considered as a solution to this problem. During the previous startup period, the ratio of the resistance value of the battery at that time to the resistance value of the battery when it is new is calculated and stored as a coefficient indicating the deterioration state of the battery (hereinafter referred to as "deterioration coefficient"). .. Then, after this start-up, the current resistance value is estimated based on the stored deterioration coefficient and the current temperature. According to this, the resistance value can be acquired immediately after the start-up and the battery can be used without waiting for the actual measurement of the resistance value after the start-up.

However, the deterioration coefficient is not completely constant even if the temperature changes in the same deterioration state, and the deterioration coefficient may change depending on the temperature even in the same deterioration state depending on the mode and temperature range of the battery. .. Therefore, if the difference between the temperature during the previous start-up period and the current temperature is large, the accuracy of estimating the current resistance value based on the previous deterioration coefficient may deteriorate.

The same problem as described above may occur not only in the case of estimating the resistance value of the battery but also in the case of estimating various characteristic values such as the charge capacity of the battery.

The present invention has been made in view of the above circumstances, and even if the difference between the battery temperature at the time of the previous deterioration determination and the current battery temperature is large, the characteristic value of the current battery can be estimated accurately. The purpose is to do so.

The battery characteristic detection device of the present invention has a detection unit and an estimation unit. In the following, the characteristic value corresponding to the temperature of the battery possessed by the deteriorated battery corresponding to the predetermined first reference time is set as the first reference value, and the deterioration corresponding to the second reference time after the first reference time is defined as the first reference value. The characteristic value of the battery according to the temperature of the battery is used as the second reference value.

The detection unit determines the deteriorated state of the battery based on the characteristic value at a predetermined first time point and the first reference value and the second reference value at the temperature of the battery at the first time point. Detects deterioration information, which is the information shown. The estimation unit estimates the characteristic value at the second time point based on the detected deterioration information and the temperature of the battery at a predetermined second time point after the first time point.

According to the present invention, the detection unit detects the deterioration information at the first time point, and the estimation unit estimates the characteristic value at the second time point based on the deterioration information and the temperature of the battery at the second time point. Therefore, the characteristic value at the second time point can be estimated in response to the temperature change.

Moreover, the deterioration information is determined based on the above-mentioned two reference values, the first reference value and the second reference value. Therefore, the deterioration information shows the deterioration state of the battery more accurately than the above-mentioned deterioration coefficient determined based on only one reference value (for example, the characteristic value at the time of new product or the characteristic value at the time of termination). Can be shown. Therefore, even if the difference between the battery temperature at the first time point and the battery temperature at the second time point is large, the deterioration information is not so affected by the temperature, and the deterioration state at each time can be shown more accurately. By estimating the characteristic value of the battery at the second time point based on the deterioration information, the estimation accuracy of the characteristic value can be improved.

Circuit diagram showing the battery characteristic detection device of the first embodiment Block diagram showing detection and estimation by the battery characteristic detection device Graph showing detection and estimation by the battery characteristic detection device Graph showing the relationship between temperature and deterioration coefficient at each deterioration value, etc. Graph showing the transition value of each value In the second embodiment, a graph showing detection and estimation by the battery characteristic detection device. In the third embodiment, a graph showing detection and estimation by the battery characteristic detection device. In the fourth embodiment, a graph showing detection and estimation by the battery characteristic detection device.

Next, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments, and can be appropriately modified and implemented without departing from the spirit of the invention.

[First Embodiment]
FIG. 1 is a circuit diagram showing the battery characteristic detection device of the first embodiment and its surroundings. In addition to the engine, the vehicle is equipped with a battery 10, a rotary electric machine 60, a load 70, and the like. A battery characteristic detection device 20 is provided for the battery 10. A start switch 80 is provided for the engine. The battery 10 has an internal resistance 13. Hereinafter, the resistance value of the internal resistance 13 is referred to as “resistance value R of the battery 10”. The battery characteristic detection device 20 includes a reference value acquisition unit 25, a detection unit 31, and an estimation unit 32.

The battery 10 is a lithium battery in this embodiment, but may be another battery. The load 70 includes various electric devices and the like. The battery 10 supplies power to the rotary electric machine 60 and the load 70. Further, the battery 10 is supplied with power by the rotary electric machine 60 to be charged.

Next, each term shown below will be described. A value indicating a deteriorated state of the battery 10 is defined as a “deteriorated value α”. In the present embodiment, this "deterioration value α" corresponds to the "deterioration information" in the present invention. The time when the battery 10 is new is referred to as "new time point tb". In the present embodiment, this "new time point tb" corresponds to the "first reference time point" in the present invention. The time point at which a predetermined period such as 10 years has passed from the new point point tb is referred to as "end point point te". In the present embodiment, this "terminal time point te" corresponds to the "second reference time point" in the present invention.

A predetermined time point after the new time point tb is referred to as "first time point t1". Specifically, in the present embodiment, the first time point t1 is the timing at which the deterioration value α is finally detected by the detection unit 31 before the start switch 80 is turned off. A predetermined time point after the first time point t1 is referred to as "second time point t2". Specifically, in the present embodiment, the second time point t2 is the timing at which the start switch 80 is first turned on after the start switch 80 is turned off after the first time point t1.

The temperature T of the battery 10 at the first time point t1 is defined as the “first temperature T1”. The temperature T of the battery 10 at the second time point t2 is defined as the “second temperature T2”. The resistance value R of the battery 10 at the first time point t1 is defined as the “first resistance value R1”. The resistance value R of the battery 10 at the second time point t2 is defined as the “second resistance value R2”.

The resistance value R of the deteriorated battery 10 corresponding to tb at the time of new product according to the temperature T is defined as "new resistance value Rb". The new resistance value Rb at the first temperature T1 is defined as the “first new resistance value Rb1”. The new resistance value Rb at the second temperature T2 is defined as the “second new resistance value Rb2”.

The resistance value R of the deteriorated battery 10 corresponding to the terminal point te according to the temperature T is defined as the “terminal resistance value Re”. The terminal resistance value Re at the first temperature T1 is defined as the “first terminal resistance value Re1”. The terminal resistance value Re at the second temperature T2 is defined as the “second terminal resistance value Re2”.

The ratio (R / Re) of the resistance value R of the battery 10 at a predetermined target time point to the terminal resistance value Re at the temperature T of the battery 10 at the target time point is defined as the “deterioration coefficient D”. In the present embodiment, this "deterioration coefficient D" corresponds to the "characteristic value" referred to in the present invention. The deterioration coefficient D at the first time point t1 is defined as the “first deterioration coefficient D1”. The deterioration coefficient D at the second time point t2 is defined as the “second deterioration coefficient D2”.

The deterioration coefficient D = R / Re possessed by the deteriorated battery 10 corresponding to tb at the time of new product according to the temperature T is defined as "new deterioration coefficient Db". In the present embodiment, this "new deterioration coefficient Db" corresponds to the "first reference value" in the present invention. The new deterioration coefficient Db at the first temperature T1 is defined as the "first new deterioration coefficient Db1". The new deterioration coefficient Db at the second temperature T2 is defined as the "second new deterioration coefficient Db2".

The deterioration coefficient D possessed by the deteriorated battery 10 corresponding to the terminal point te is referred to as the “terminal deterioration coefficient De”. In the present embodiment, this "terminal deterioration coefficient De" corresponds to the "second reference value" in the present invention. Since the terminal deterioration coefficient De is "Re / Re", it is inevitably "1". The terminal deterioration coefficient De at the first temperature T1 is defined as the “first terminal deterioration coefficient De1”. The terminal deterioration coefficient De at the second temperature T2 is defined as the “second terminal deterioration coefficient De2”. Both the first terminal deterioration coefficient De1 and the second terminal deterioration coefficient De2 inevitably become "1".

Next, the battery characteristic detection device 20 will be described. The reference value acquisition unit 25 has a map showing the relationship between the temperature T of the battery 10 and the new resistance value Rb, and a map showing the relationship between the temperature T of the battery 10 and the terminal resistance value Re. These maps are acquired in advance based on experiments or the like, or are acquired in advance based on the specifications of the battery 10 or the like. From those maps, the reference value acquisition unit 25 can acquire a new resistance value Rb and a terminal resistance value Re at the temperature T at the target time point, if necessary. Further, the new deterioration coefficient Db = Rb / Re can be obtained from the new resistance value Rb and the terminal resistance value Re. The reference value acquisition unit 25 provides the acquired numerical value to the detection unit 31.

The detection unit 31 detects the deterioration value α based on the first deterioration coefficient D1, the first new deterioration coefficient Db1, and the first terminal deterioration coefficient De1. The estimation unit 32 estimates the second deterioration coefficient D2 based on the deterioration value α, the second new deterioration coefficient Db2, and the second terminal deterioration coefficient De2.

FIG. 2 is a block diagram showing detection, estimation, and the like by the battery characteristic detection device 20. First, the detection unit 31 calculates the first resistance value R1 from the voltage value and the current value in the battery 10 at the first time point t1 (S101). Further, the reference value acquisition unit 25 calculates the first new resistance value Rb1, the first terminal resistance value Re1, and the first new deterioration coefficient Db1 = Rb1 / Re1 from the first temperature T1 (S102).

Next, the detection unit 31 calculates the first deterioration coefficient D1 = R1 / Re1 from the first resistance value R1 and the first terminal resistance value Re1 (S103). Next, the detection unit 31 calculates the deterioration value α based on the first deterioration coefficient D1, the first new deterioration coefficient Db1, and the first terminal deterioration coefficient De1 = 1 (S104). The details of this calculation will be described later.

Next, the reference value acquisition unit 25 calculates the second new resistance value Rb2, the second terminal resistance value Re2, and the second new deterioration coefficient Db2 = Rb2 / Re2 from the second temperature T2 (S105). Next, the estimation unit 32 estimates the second deterioration coefficient D2 based on the deterioration value α, the second new deterioration coefficient Db2, and the second terminal deterioration coefficient De2 = 1 (S106). The details of this calculation will be described later. Next, the estimation unit 32 calculates the second resistance value R2 based on the second deterioration coefficient D2 = R2 / Re2 and the second terminal resistance value Re2 (S107).

Next, the calculated second resistance value R2 and the deterioration value α calculated in the calculation process are used (S108). Specifically, for example, information on the output from the battery 10 to the rotary electric machine 60 is required based on the second resistance value R2. Further, for example, based on the second resistance value R2, information regarding the output to each of the other loads 70 is also required. Further, for example, information on the life of the battery 10 and the like is required based on the deterioration value α.

FIG. 3 is a graph showing the relationship between the temperature T of the battery 10 and the deterioration coefficient D. If the rate of change of the new resistance value Rb and the terminal resistance value Re with respect to the temperature T is different, the new deterioration coefficient Db = Rb / Re will not be constant and will change depending on the temperature T. In that respect, in the present embodiment, when the temperature is less than the predetermined temperature Tx shown in FIG. 3A, the new deterioration coefficient Db is not constant and changes depending on the temperature T. On the other hand, since the terminal deterioration coefficient De = Re / Re is always "1", it does not change with the temperature T.

Therefore, when the temperature is less than the predetermined temperature Tx, the new deterioration coefficient Db and the terminal deterioration coefficient De are not parallel. In this case, the correct deterioration state cannot be estimated even if the deterioration value α is obtained only based on the new deterioration coefficient Db or the deterioration value α is obtained based only on the terminal deterioration coefficient De. Therefore, the deterioration value α is obtained based on both the new deterioration coefficient Db and the terminal deterioration coefficient De. The second resistance value R2 is estimated based on the deterioration value α.

First, the calculation of the deterioration value α in S104 will be described with reference to FIGS. 3A to 3C. First, as shown in FIG. 3A, the graph showing the relationship between the deterioration coefficient D and the temperature T shows the state of the battery 10 at the first time point t1, that is, the first temperature T1 and the first deterioration coefficient D1. The first point P1 = (T1, D1), which is a point indicating, is plotted.

Next, as shown in FIG. 3B, the first new point Pb1 is a point showing the new deterioration coefficient Db at the first temperature T1, that is, the point showing the first temperature T1 and the first new deterioration coefficient Db1. = (T1, Db1) is plotted. Further, the first terminal point Pe1 = (T1,1), which is a point indicating the terminal deterioration coefficient De at the first temperature T1, that is, a point indicating the first temperature T1 and the first terminal deterioration coefficient De1 = 1, is plotted. ..

Next, as shown in FIG. 3C, when the difference (1-Db1) between the first end point Pe1 and the first new point Pb1 is set to 1 (reference difference), the first point P1 and the first point The magnitude (D1-Db1) / (1-Db1) of the difference (D1-Db1) from the new point Pb1 is calculated as the deterioration value α.

Next, with reference to FIGS. 3 (d) and 3 (e), the estimation of the second deterioration coefficient D2 in S106 will be described. As shown in FIG. 3D, the second new point Pb2 = (T2), which is a point showing the new deterioration coefficient Db at the second temperature T2, that is, a point showing the second temperature T2 and the second new deterioration coefficient Db2. , Db2) is plotted. Further, a second terminal point Pe2 = (T2, 1), which is a point indicating the terminal deterioration coefficient De at the second temperature T2, that is, a point indicating the second temperature T2 and the second terminal deterioration coefficient De2 = 1, is plotted. ..

Next, as shown in FIG. 3 (e), the numerical value α × (1-Db2) obtained by multiplying the difference (1-Db2) between the second terminal point Pe2 and the second new point Pb2 by the deterioration value α is calculated. , The numerical value α × (1-Db2) is added to the coordinates (Db2) of the deterioration coefficient D of the second new point Pb2 = (T2, Db2) to calculate the point. That point is estimated as the second point P2 = (T2, D2). As a result, the second deterioration coefficient D2 is estimated.

FIG. 4A is a graph showing the relationship between the deterioration coefficient D and the temperature T at each deterioration value α. FIG. 4B is an image diagram showing the relationship between the deterioration coefficient D and the temperature T at each equivalent deterioration age Y. The equivalent number of years of deterioration Y is a value indicating how many years the battery 10 has deteriorated. As described above, since the relationship between the deterioration coefficient D and the temperature T when the deterioration value α is constant and the relationship between the deterioration coefficient D and the temperature T when the equivalent deterioration years Y are constant are similar, the deterioration value α The considerable deterioration years Y can be calculated from.

FIG. 5 is a graph showing the transition of each value when the deterioration value α is detected at the first time point t1 and the second resistance value R2 is estimated at the second time point t2 as described above. Specifically, FIG. 5A is a graph showing the transition of ON / OFF of the start switch 80. In the following, turning on the start switch 80 is simply referred to as "start on", and turning off the start switch 80 is simply referred to as "start off". FIG. 5B is a graph showing the transition of the temperature T of the battery 10. FIG. 5C is a graph showing the actual measurement timing of the resistance value R. FIG. 5D is a graph showing the transition of the resistance value R of the battery 10. FIG. 5 (e) is a graph showing the transition of the deterioration coefficient D. FIG. 5 (f) is a graph showing the transition of the deterioration value α.

As shown in FIG. 5A, the first resistance value R1 is actually measured at the first time point t1 during the activation ON period, as shown in FIG. 5C. As a result, as shown in FIGS. 5 (d) to 5 (f), the first resistance value R1, the first deterioration coefficient D1, and the deterioration value α are detected. Next, as shown in FIG. 5A, the start-off is turned off at a predetermined start-off time point ti after the first time point t1.

As shown in FIG. 5B, it is assumed that the temperature T of the battery 10 has changed since the start-off time ti. Along with this, the actual resistance value R changes as shown by the broken line in FIG. 5 (d), and the actual deterioration coefficient D also changes slightly as shown by the broken line in FIG. 5 (e). However, as shown by the broken line in FIG. 5 (f), the deterioration value α hardly changes.

Next, as shown in FIG. 5 (a), when the start is turned on at the second time point t2 after the start-off time ti, as shown in FIGS. 5 (d) to 5 (f), the stored deterioration value α The second deterioration coefficient D2 is estimated based on the above, and the second resistance value R2 is calculated based on the second deterioration coefficient D2.

On the other hand, in the case of the comparative example, it is assumed that the first deterioration coefficient D1 is stored instead of the deterioration value α, and the resistance value R at the second time point t2 is estimated based on the first deterioration coefficient D1. In that case, since the first deterioration coefficient D1 is different from the actual deterioration coefficient D at the second time point t2, the resistance value R calculated from the first deterioration coefficient D1 is also different from the actual resistance value R.

Next, as shown in FIG. 5C, the actual resistance value R is actually measured at the actual measurement time point tj after the second time point t2. Therefore, in the present embodiment, as shown in FIGS. 5 (d) and 5 (e), the deterioration coefficient D and the resistance value R, which are closer to the actual ones than in the comparative example, are estimated between the second time point t2 and the actual measurement time point tj. can do.

According to the present embodiment, by estimating the second resistance value R2, the resistance value R can be immediately grasped at the second time point t2 without waiting for the actual measurement of the resistance value R at the actual measurement time point tj. Therefore, the battery 10 can be used immediately after the second time point t2, and the period during which the battery 10 can be used increases. Therefore, the period during which the rotary electric machine 60 can be driven and the period during which the rotary electric machine 60 can generate regenerative power generation increase, and fuel efficiency is improved.

Further, in the present embodiment, the deterioration value α and the second resistance value R2 are calculated based on the deterioration coefficient D. Therefore, when it is necessary to obtain the deterioration coefficient D for other purposes, the deterioration coefficient D is used. The deterioration value α and the second resistance value R2 can be calculated. Further, since the terminal deterioration coefficient De = Re / Re is always set to "1" by using the deterioration coefficient D = R / Re, the reference value acquisition unit 25 sets the first terminal deterioration coefficient De1 and the second terminal deterioration coefficient De2. You don't have to get it, which simplifies the calculation. Further, the deterioration information can be simplified by setting the deterioration information to the numerical deterioration value α. Further, the time when the deterioration value α is finally detected by the detection unit 31 before the start switch 80 is turned off is set to the first time point t1, so that the latest deterioration value α is used as much as possible at the second time point t2. The resistance value R can be estimated.

[Second Embodiment]
Next, the second embodiment will be described. In the following embodiments, the same or corresponding members as those of the previous embodiments are designated by the same reference numerals. The present embodiment will be described based on the first embodiment, focusing on the differences. In the present embodiment, the iso-deterioration line β is obtained instead of the deterioration value α. In the present embodiment, this "iso-deterioration line β" corresponds to the "deterioration information" in the present invention.

FIG. 6 is a graph showing the relationship between the temperature T of the battery 10 and the deterioration coefficient D. The detection of the isodegradation line β and the estimation of the second deterioration coefficient D2 will be described below. First, as shown in FIG. 6A, the first point P1 = (T1, D1) is plotted.

Next, as shown in FIG. 6B, the isodegradation line β passing through the first point P1 is calculated. The isodegradation line β is a line showing the relationship between the deterioration coefficient D and the temperature T of the battery 10 in the same deterioration state of the battery 10. The isodegradation line β is determined based on the new deterioration coefficient Db and the terminal deterioration coefficient De. Therefore, the isodegradation line β is drawn along both the line showing the new deterioration coefficient Db and the line showing the terminal deterioration coefficient De = 1 on average. Specifically, the isodegradation line β can be, for example, a set of points at which the deterioration values α in the first embodiment have the same value.

In the comparative example shown by the broken line in the figure, when the line where the deterioration coefficient D = R / Re is constant is set to the equal deterioration line β, that is, the terminal deterioration coefficient is not based on the new deterioration coefficient Db = Rb / Re. The case where the isodegradation line β is drawn based on De = Re / Re = 1 is shown. In the case of this comparative example, the iso-deterioration line β follows the line showing the terminal deterioration coefficient De = 1, but as in the case of the present embodiment, the line showing the new deterioration coefficient Db and the terminal deterioration coefficient De = 1 are set. It does not follow both the lines shown on average.

Next, as shown in FIG. 6C, the intersection of the second temperature T2 and the isodegradation line β is calculated as the second point P2 = (T2, D2).

According to the present embodiment, by obtaining the isodegradation line β, the isodegradation line β can be obtained without obtaining the first new point Pb1, the first terminal point Pe1, the second new point Pb2, and the second terminal point Pe2. The second deterioration coefficient D2 can be estimated directly from the second temperature T2.

[Third Embodiment]
Next, the third embodiment will be described. The present embodiment will be described with reference to the second embodiment, focusing on differences from the second embodiment. In the present embodiment, the second resistance value R2 is estimated directly from the first resistance value R1 without obtaining the first deterioration coefficient D1 and the second deterioration coefficient D2. Specifically, the second resistance value R2 is estimated from the first resistance value R1 by using the isodegrade line γ different from the isodegrade line β.

Therefore, in the present embodiment, the “resistance value R” itself, not the “deterioration coefficient D = R / Re”, corresponds to the “characteristic value” in the present invention. Then, the "iso-deterioration line γ" corresponds to the "deterioration information" in the present invention.

FIG. 7 is a graph showing the relationship between the temperature T of the battery 10 and the resistance value R. The detection of the isodegradation line γ and the estimation of the second resistance value R2 will be described below. First, as shown in FIG. 7A, the first point P1 = (T1, R1) is plotted.

Next, as shown in FIG. 7B, the equi-degradation line γ passing through the first point P1 is calculated. The isodegradation line γ is a line showing the relationship between the resistance value R and the temperature T of the battery 10 in the same deterioration state of the battery 10. The isodegradation line γ is determined based on the new resistance value Rb and the terminal resistance value Re. Therefore, the isodegradation line γ is drawn along both the line showing the new resistance value Rb and the line showing the terminal resistance value Re on average.

In the comparative example shown by the broken line in the figure, when the set of points having the same deterioration coefficient D = R / Re is set to the equi-deterioration line γ, that is, the terminal resistance value Re is not based on the new resistance value Rb. It shows the case where the isodegradation line γ is drawn based on the above. In the case of this comparative example, the isodegradation line γ follows the line indicating the terminal resistance value Re, but as in the case of the present embodiment, the line indicating the new resistance value Rb and the line indicating the terminal resistance value Re Both are not on average.

Next, as shown in FIG. 7C, the intersection of the second temperature T2 and the isodegradation line γ is calculated as the second point P2 = (T2, R2).

According to this embodiment, the second resistance value R2 is estimated directly from the first resistance value R1 without obtaining the first deterioration coefficient D1 = R1 / Re1 and the second deterioration coefficient D2 = R2 / Re2. Can be done.

[Fourth Embodiment]
Next, the fourth embodiment will be described. The present embodiment will be described with reference to the second embodiment, focusing on differences from the second embodiment.

FIG. 8 is a graph showing the relationship between the temperature T of the battery 10 and the resistance value R. In this embodiment, the isodegradation line β changes stepwise. According to the present embodiment, the amount of information on the isodegradation line β can be reduced, thereby simplifying the process.

[Other Embodiments]
The present embodiment may be modified and implemented as follows, for example. The engine may be changed to a motor or a power unit for various traveling such as a hybrid of the engine and the motor. Instead of the new time point tb, a one year equivalent deterioration time point may be used. Instead of the terminal point te, a point of deterioration equivalent to 5 years may be used.

In the first, second, and fourth embodiments, instead of setting the deterioration coefficient D to the ratio (R / Re) of the terminal resistance value Re and the resistance value R at the target time point, the new resistance value Rb and the target time point are used. The ratio (R / Rb) to the resistance value R of In this case, the new deterioration coefficient Db is always "1" instead of the terminal deterioration coefficient De.

Based on the second embodiment, the present invention is based on the first and fourth embodiments, as in the case where the "characteristic value" referred to in the present invention is changed from the deterioration coefficient D to the resistance value R to the third embodiment. The "characteristic value" referred to in the invention may be changed from the deterioration coefficient D to the resistance value R. In this case, in the embodiment based on the first and fourth embodiments, the first deterioration coefficient D1 = R1 / Re1 and the second deterioration coefficient D2 = R2 / Re2 are not obtained as in the case of the third embodiment. Also, the second resistance value R2 can be estimated directly from the first resistance value R1.

Instead of calculating the deterioration value α and the iso-deterioration lines β and γ at the timing before each start-off, the deterioration value α and the iso-deterioration lines β and γ may be calculated once in a predetermined period such as once a month. This is because the time change of the deteriorated state is usually gradual.

The second resistance value R2 is estimated by the deterioration value α and the isodegradation lines β and γ only when the difference between the first temperature T1 and the second temperature T2 is equal to or more than a predetermined value, and in other cases, the first resistance is estimated. The value R1 may be inherited as the second resistance value R2, or the first deterioration coefficient D1 may be inherited as the second deterioration coefficient D2.

Both the change ratio of the new deterioration coefficient Db with respect to the temperature T and the change ratio of the terminal deterioration coefficient De with respect to the temperature T may be the same. Even in this case, the battery characteristic detection device 20 has an effect that the two change ratios can be dealt with even if they are the same or different.

When the resistance value R changes not a little due to the difference in the charge amount (SOC) of the battery 10, the second resistance value R2 may be further corrected based on the charge amount.

The battery capacity may be used instead of the resistance value R. That is, in the first, second, and fourth embodiments, instead of setting the deterioration coefficient D to the ratio (R / Re) of the terminal resistance value Re and the resistance value R at the target time point, the terminal battery capacity and the target It may be the ratio of the battery capacity at the time. Further, in the third embodiment, the resistance value R may be replaced with the battery capacity.

α ... deterioration value, β ... iso-deterioration line, γ ... iso-deterioration line, 10 ... battery, 20 ... battery characteristic detection device, 31 ... detection unit, 32 ... estimation unit, D ... deterioration coefficient, D1 ... first deterioration coefficient, D2 ... 2nd deterioration coefficient, Db ... New deterioration coefficient, De1 ... 1st terminal deterioration coefficient, R ... Resistance value, R1 ... 1st resistance value, R2 ... 2nd resistance value, Rb ... New resistance value, Re ... Terminal resistance Value, T ... temperature, T1 ... first temperature, T2 ... second temperature, t1 ... first time point, t2 ... second time point, tb ... new time point, te ... terminal time point.

Claims (7)

The characteristic values (D, R) corresponding to the temperature (T) of the battery possessed by the deteriorated battery corresponding to the predetermined first reference time point (tb) are set as the first reference value (Db, Rb), and the first reference value (Db, Rb) is defined. The characteristic value according to the temperature of the battery possessed by the battery having deteriorated equivalent to the second reference time point (te) after the reference time point is set as the second reference point value (De, Re).
Based on the characteristic values (D1, R1) at a predetermined first time point (t1) and the first reference value and the second reference value at the battery temperature (T1) at the first time point. A detection unit (31) that detects deterioration information (α, β, γ), which is information indicating the deterioration state of the battery, and
Based on the detected deterioration information and the temperature (T2) of the battery at a predetermined second time point (t2) after the first time point, the characteristic value (D2, R2) at the second time point is used. ), And the estimation unit (32)
Battery characteristic detection device with. The battery characteristic detection device according to claim 1, wherein the characteristic value is a value based on the internal resistance value (R) of the battery. The characteristic value is the physical property value (R) of the battery at a predetermined target time point and the physical property value (Re) of the battery having deteriorated at a predetermined reference time point (te) if the temperature is the temperature of the target time point. ) And the ratio (D) of the battery characteristic detection device according to claim 1 or 2. The deterioration information is based on the difference between the first reference value and the second reference value at the battery temperature at the first time point as the reference difference, and the first reference value at the battery temperature at the first time point. Any of claims 1 to 3, which is the ratio (α) between the reference difference and the target difference when the difference between the value or the second reference value and the characteristic value at the first time point is taken as the target difference. The battery characteristic detection device according to item 1. The deterioration information is any one of claims 1 to 3, which is information (β, γ) indicating the relationship between the characteristic value and the temperature of the battery in the deteriorated state of the battery at the first time point. The battery characteristic detection device described in. The battery is a battery mounted on a vehicle.
The first time point is any of claims 1 to 5, which is a timing at which the deterioration information is finally detected by the detection unit before the start switch (80) of the power unit for traveling the vehicle is turned off. The battery characteristic detection device according to item 1. The battery characteristic according to any one of claims 1 to 6, wherein the change ratio of the first reference value to the temperature and the change ratio of the second reference value to the temperature are different from each other in at least a part of the temperature range. Detection device.

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