JP7207100B2 - Battery characteristic detector - Google Patents

Description

The present invention relates to a battery characteristic detection device for detecting characteristic values of a battery.

2. Description of the Related Art Some control devices for batteries mounted on vehicles detect the internal resistance value of the battery and control the use of the battery based on the detected resistance value. As a document showing such a technique, there is the following Patent Document 1.

JP 2018-148720 A

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

On the other hand, it is not possible to save the resistance value of the battery during the previous start-up period and take over the previous resistance value after the current start-up. This is because the resistance value of the battery depends on the temperature, so if the temperature of the battery during the previous start-up period differs from the temperature of the battery at the time of the current start-up, the resistance value of the battery will also differ.

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

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

It should be noted that problems similar to those described above may occur not only when estimating the resistance value of a battery, but also when 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 can accurately estimate the current characteristic value of the battery even if the difference between the battery temperature at the time of the previous deterioration determination and the current battery temperature is large. The purpose is to

A battery characteristic detecting device of the present invention has a detecting section and an estimating section. Hereinafter, a characteristic value corresponding to the temperature of the battery possessed by a battery having deteriorated at a predetermined first reference point is defined as a first reference value, and the deterioration corresponding to a second reference point after the first reference point is defined as a first reference value. The characteristic value of the battery, which corresponds to the temperature of the battery, is defined as a second reference value.

The detection unit detects the deterioration 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 for the temperature of the battery at the first time point. Deterioration information, which is the information indicating, is detected. The estimator estimates the characteristic value at the second point in time based on the detected deterioration information and the temperature of the battery at a predetermined second point in time after the first point in time.

According to the present invention, the detection section detects the deterioration information at the first time point, and the estimation section 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 point in time can be estimated in response to the temperature change.

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

1 is a circuit diagram showing a battery characteristic detection device according to a first embodiment; FIG. Block diagram showing detection and estimation by the battery characteristic detector Graph showing detection and estimation by battery characteristic detector Graph showing the relationship between temperature and deterioration coefficient for each deterioration value A graph showing transition values for each value Graph showing detection and estimation by the battery characteristic detection device in the second embodiment Graph showing detection and estimation by the battery characteristic detection device in the third embodiment Graph showing detection and estimation by the battery characteristic detection device in the fourth embodiment

Next, embodiments 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 modified as appropriate without departing from the gist of the invention.

[First embodiment]
FIG. 1 is a circuit diagram showing the battery characteristics detection device of the first embodiment and its periphery. The vehicle is equipped with a battery 10, a rotating electric machine 60, a load 70, etc., in addition to an engine. A battery characteristic detection device 20 is provided for the battery 10 . A start switch 80 is provided for the engine. Battery 10 has internal resistance 13 . The resistance value of the internal resistance 13 is hereinafter referred to as "the resistance value R of the battery 10". The battery characteristic detection device 20 has a reference value acquisition section 25 , a detection section 31 and an estimation section 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 rotating electric machine 60 and the load 70 . Also, the battery 10 is charged by power supplied by the rotating electric machine 60 .

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

A predetermined time point after the new product time point tb is defined as "first time point t1". Specifically, in this embodiment, the first time point t1 is the timing at which the detection unit 31 finally detects the deterioration value α before the start switch 80 is turned off. A predetermined time point after the first time point t1 is defined as a "second time point t2". Specifically, in this embodiment, the second time point t2 is the timing at which the start switch 80 is turned on for the first time 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 t1 is defined as "first temperature T1". The temperature T of the battery 10 at the second time t2 is defined as "second temperature T2". Let the resistance value R of the battery 10 at the first time point t1 be “first resistance value R1”. Let the resistance value R of the battery 10 at the second time t2 be a “second resistance value R2”.

The resistance value R of the battery 10 that has deteriorated corresponding to the time point tb when it is new, according to the temperature T, is defined as "new resistance value Rb". The new product resistance value Rb at the first temperature T1 is defined as "first new product resistance value Rb1". The new product resistance value Rb at the second temperature T2 is defined as "second new product resistance value Rb2".

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

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

A deterioration coefficient D=R/Re that the battery 10 having deteriorated corresponding to the time tb when new has according to the temperature T is defined as a “new deterioration coefficient Db”. In this embodiment, this "new product deterioration coefficient Db" corresponds to the "first reference value" of the present invention. The new article deterioration coefficient Db at the first temperature T1 is defined as "first new article deterioration coefficient Db1". The new article deterioration coefficient Db at the second temperature T2 is defined as "second new article deterioration coefficient Db2".

A deterioration coefficient D of the battery 10 having deterioration corresponding to the terminal time te is defined as a “terminal deterioration coefficient De”. In this embodiment, the "terminal deterioration coefficient De" corresponds to the "second reference value" of 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 "first terminal deterioration coefficient De1". The terminal deterioration coefficient De at the second temperature T2 is defined as “second terminal deterioration coefficient De2”. Both the first terminal deterioration factor De1 and the second terminal deterioration factor De2 are necessarily "1".

Next, the battery characteristics detection device 20 will be described. The reference value acquiring 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 these maps, the reference value acquisition unit 25 can acquire the new resistance value Rb and the terminal resistance value Re at the temperature T at the target time, if necessary. Furthermore, a new product deterioration coefficient Db=Rb/Re can be obtained from the new product 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 product 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 product deterioration coefficient Db2, and the second terminal deterioration coefficient De2.

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

Next, the detection unit 31 calculates a 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 product 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 acquiring unit 25 calculates a second new product resistance value Rb2, a second terminal resistance value Re2, and a second new product 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 product 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 regarding the output from the battery 10 to the rotating electric machine 60 is obtained based on the second resistance value R2. Further, for example, based on the second resistance value R2, information regarding output to other loads 70 is also obtained. Further, for example, information regarding the life of the battery 10 is obtained 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. As shown in FIG. If the rate of change with respect to the temperature T is different between the new product resistance value Rb and the terminal resistance value Re, the new product deterioration coefficient Db=Rb/Re will not be constant and will change with the temperature T. In this regard, in the present embodiment, the new product deterioration coefficient Db is not constant below the predetermined temperature Tx shown in FIG. On the other hand, since the terminal deterioration coefficient De=Re/Re is always "1", it does not change with the temperature T.

Therefore, below the predetermined temperature Tx, the new article deterioration coefficient Db and the terminal deterioration coefficient De are not parallel. In this case, even if the deterioration value α is obtained based only on the new product deterioration coefficient Db, or if the deterioration value α is obtained based only on the terminal deterioration coefficient De, the correct deterioration state cannot be estimated. Therefore, the deterioration value α is obtained based on both the new product deterioration coefficient Db and the terminal deterioration coefficient De. A 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. First, as shown in FIG. 3A, points indicating the state of the battery 10 at the first time point t1, that is, the first temperature T1 and the first deterioration coefficient D1, are shown in the graph showing the relationship between the deterioration coefficient D and the temperature T. Plot the first point P1=(T1, D1), which is a point indicating .

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

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

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

Next, as shown in FIG. 3(e), a numerical value α×(1−Db2) is calculated by multiplying the difference (1−Db2) between the second end point Pe2 and the second new point Pb2 by the deterioration value α. , 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). The point is estimated as the second point P2=(T2, D2). Thereby, the second deterioration coefficient D2 is estimated.

FIG. 4A is a graph showing the relationship between the deterioration coefficient D and the temperature T for each deterioration value α. FIG. 4(b) is an image diagram showing the relationship between the deterioration coefficient D and the temperature T for each equivalent deterioration years Y. As shown in FIG. The equivalent deterioration years Y is a value indicating how many years the battery 10 has deteriorated. Thus, the relationship between the deterioration coefficient D and the temperature T when the deterioration value α is constant is similar to the relationship between the deterioration coefficient D and the temperature T when the equivalent deterioration years Y are constant. Equivalent deterioration years Y can be calculated from the above.

FIG. 5 is a graph showing changes in values 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. 5(a) is a graph showing the ON/OFF transition of the start switch 80. As shown in FIG. Hereinafter, turning on the start switch 80 is simply referred to as "starting on", and turning off the start switch 80 is simply referred to as "starting off". FIG. 5(b) is a graph showing transition of the temperature T of the battery 10. As shown in FIG. FIG. 5(c) is a graph showing the actual measurement timing of the resistance value R. As shown in FIG. FIG. 5(d) is a graph showing transition of the resistance value R of the battery 10. As shown in FIG. FIG. 5(e) is a graph showing transition of the deterioration coefficient D. FIG. FIG. 5(f) is a graph showing transition of the deterioration value α.

As shown in FIG. 5(a), the first resistance value R1 is actually measured at a first time point t1 during the startup ON period, as shown in FIG. 5(c). Thereby, 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-up is turned off at a predetermined start-off time ti after the first time t1.

As shown in FIG. 5(b), it is assumed that the temperature T of the battery 10 has changed after the startup OFF time ti. Accordingly, the actual resistance value R changes as indicated by the broken line in FIG. 5(d), and the actual deterioration coefficient D also slightly changes as indicated by the broken line in FIG. 5(e). However, as indicated by the dashed line in FIG. 5(f), the deterioration value α hardly changes.

Next, as shown in FIG. 5A, when the activation is turned ON at the second time t2 after the activation OFF time ti, the stored deterioration value α and a second resistance value R2 is calculated based on the second deterioration coefficient D2.

On the other hand, in the case of the comparative example, 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 this case, since the first deterioration coefficient D1 differs from the actual deterioration coefficient D at the second time point t2, the resistance value R calculated therefrom also differs from the actual resistance value R.

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

According to this 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 t2, and the period during which the battery 10 can be used increases. Therefore, the period during which the rotating electrical machine 60 can be driven and the period during which the rotating electrical machine 60 can perform regenerative power generation are increased, thereby improving fuel efficiency.

Further, in the present embodiment, since the deterioration value α and the second resistance value R2 are calculated based on the deterioration coefficient D, the deterioration coefficient D can be used when the deterioration coefficient D needs to be obtained for other purposes. can be used to calculate the deterioration value α and the second resistance value R2. Further, by using the deterioration coefficient D=R/Re, the terminal deterioration coefficient De=Re/Re is always “1”, so the reference value acquisition unit 25 obtains the first terminal deterioration coefficient De1 and the second terminal deterioration coefficient De2. There is no need to obtain it, which simplifies the calculation. Further, the deterioration information can be simplified by using the deterioration value α, which is a numerical value, as the deterioration information. Further, by setting the time point at which the detection unit 31 last detects the deterioration value α before the start switch 80 is turned off as the first time point t1, the latest deterioration value α can be used at the second time point t2 as much as possible. can be estimated.

[Second embodiment]
Next, a second embodiment will be described. In the following embodiments, members that are the same as or correspond to those in the previous embodiments are denoted by the same reference numerals. This embodiment will be described based on the first embodiment, focusing on points that differ from it. In the present embodiment, iso-deterioration lines β are obtained instead of the deterioration value α. In this embodiment, the "equivalent deterioration line β" corresponds to "deterioration information" in the present invention.

FIG. 6 is a graph showing the relationship between the temperature T and the deterioration coefficient D of the battery 10. As shown in FIG. Detection of the iso-deterioration line β and 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, iso-degradation lines β passing through the first point P1 are calculated. The constant deterioration 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 iso-deterioration line β is determined based on the new product deterioration coefficient Db and the terminal deterioration coefficient De. Therefore, the iso-deterioration line β is drawn along the average along both the line indicating the new product deterioration coefficient Db and the line indicating the terminal deterioration coefficient De=1. Specifically, the iso-degradation line β can be, for example, a set of points at which the degradation value α in the first embodiment has the same value.

In the comparative example indicated by the dashed line in the figure, when the line where the deterioration coefficient D=R/Re is constant is set to the constant deterioration line β, that is, the terminal deterioration coefficient is not based on the new product deterioration coefficient Db=Rb/Re. It shows the case where the iso-deterioration line β is drawn based on De=Re/Re=1. In the case of this comparative example, the iso-deterioration line β follows the line indicating the terminal deterioration coefficient De=1. It does not follow both the indicated line and the line on average.

Next, as shown in FIG. 6C, the intersection point between the second temperature T2 and the iso-degradation line β is calculated as a second point P2=(T2, D2).

According to the present embodiment, even if the first new point Pb1, the first terminal point Pe1, the second new point Pb2, and the second terminal point Pe2 are not obtained by obtaining the iso-degradation line β, the iso-degradation line β The second deterioration coefficient D2 can be estimated directly from the second temperature T2.

[Third embodiment]
Next, a third embodiment will be described. This embodiment will be described based on the second embodiment, focusing on the differences therefrom. In this 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 using an iso-degradation line γ different from the iso-degradation line β.

Therefore, in the present embodiment, the "resistance value R" itself, not the "degradation coefficient D=R/Re", corresponds to the "characteristic value" of the present invention. The "equal deterioration line γ" corresponds to "deterioration information" in the present invention.

FIG. 7 is a graph showing the relationship between temperature T and resistance value R of battery 10 . Detection of the iso-degradation line γ and 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. 7(b), an iso-degradation line γ passing through the first point P1 is calculated. The constant deterioration 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 iso-degradation line γ is determined based on the new resistance value Rb and the terminal resistance value Re. Therefore, the iso-degradation line γ is drawn along both the line indicating the new resistance value Rb and the line indicating the terminal resistance value Re on average.

In the comparative example indicated by the dashed line in the figure, when the set of points where the deterioration coefficient D=R/Re is the same is set as the iso-degradation line γ, that is, it is not based on the new resistance value Rb, but on the terminal resistance value Re. It shows the case where the iso-degradation line γ is drawn based on the above. In the case of this comparative example, the iso-degradation line γ follows the line indicating the terminal resistance value Re. There is no average for both.

Next, as shown in FIG. 7C, the intersection point between the second temperature T2 and the iso-degradation line γ is calculated as a second point P2=(T2, R2).

According to the present embodiment, the second resistance value R2 can be 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, a fourth embodiment will be described. This embodiment will be described based on the second embodiment, focusing on the differences therefrom.

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

[Other embodiments]
For example, the present embodiment can be modified as follows. The engine may be changed to various driving power devices such as a motor, a hybrid of an engine and a motor, or the like. Instead of the new product time tb, the deterioration time corresponding to one year may be used. Instead of the terminal time te, a 5-year equivalent deterioration time may be used.

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

Based on the second embodiment, the present invention is based on the first and fourth embodiments, similarly to the case where the "characteristic value" referred to in the present invention is replaced with the resistance value R instead of the deterioration coefficient D in the third embodiment. The "characteristic value" referred to in the invention may be replaced with the resistance value R instead of the deterioration coefficient D. In this case, in a mode based on the first and fourth embodiments, similarly to the case of the third embodiment, the first deterioration factor D1=R1/Re1 and the second deterioration factor D2=R2/Re2 need not be obtained. 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-degradation lines β and γ before each start-off, the calculation may be performed once in a predetermined period such as once a month. This is because the time change of the deterioration state is usually moderate.

Estimation of the second resistance value R2 based on the deterioration value α and the iso-degradation lines β and γ is performed only when the difference between the first temperature T1 and the second temperature T2 is equal to or greater than a predetermined value. The value R1 may be taken over as the second resistance value R2, or the first deterioration coefficient D1 may be taken over as the second deterioration coefficient D2.

Both the change ratio of the new product 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 the effect of being able to cope with both the same change ratios and different ratios.

If the resistance value R changes considerably due to the difference in the charge level (SOC) of the battery 10, the second resistance value R2 may be further corrected based on the charge level.

A 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) between the terminal resistance value Re and the resistance value R at the target time, the terminal battery capacity and the target It may be the ratio of the battery capacities at that time. Also, in the third embodiment, the resistance value R may be replaced with the battery capacity.

α... Deterioration value, β... Equal deterioration line, γ... Equal deterioration line, 10... Battery, 20... Battery characteristic detection device, 31... Detecting unit, 32... Estimating unit, D... Deterioration coefficient, D1... First deterioration coefficient, D2: second deterioration coefficient, Db: new product deterioration coefficient, De1: first terminal deterioration coefficient, R: resistance value, R1: first resistance value, R2: second resistance value, Rb: new product resistance value, Re: terminal resistance Value, T...Temperature, T1...First temperature, T2...Second temperature, t1...First point in time, t2...Second point in time, tb...New article point in time, te...Terminal point in time.

Claims (5)

A characteristic value ( D) corresponding to the temperature (T) of the battery possessed by the battery having deteriorated corresponding to the predetermined first reference time (tb) is defined as a first reference value ( Db) , and from the first reference time As a second reference value ( De) , the characteristic value corresponding to the temperature of the battery possessed by the battery that has deteriorated corresponding to the second reference time (te) afterward,
Based on the characteristic value (D1) 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) that is information indicating the deterioration state of the battery;
the characteristic value (D2 ) at the second time based on the detected deterioration information and the temperature (T2) of the battery at a predetermined second time (t2) after the first time; an estimating unit (32) for estimating
has
The characteristic value is a predetermined physical property value of the battery at the target temperature for which the characteristic value is to be obtained, and the physical property of the battery that has deteriorated corresponding to the first reference time or the second reference time at the target temperature. A battery characteristic detection device , which is the ratio (D) of the value and The deterioration information is the reference difference between the first reference value and the second reference value of the temperature of the battery at the first time, and the first reference of the temperature of the battery at the first time. 2. The battery according to claim 1 , which is a ratio (α) between the reference difference and the target difference when the target difference is the difference between the value or the second reference value and the characteristic value at the first time point. Characteristic detector. 2. The battery characteristic detection device according to claim 1 , wherein said deterioration information is information (β, γ) indicating a relationship between said characteristic value and temperature of said battery in said deterioration state of said battery at said first point in time. . A characteristic value (D, R) corresponding to the temperature (T) of the battery possessed by the battery having deteriorated corresponding to the predetermined first reference time (tb) is defined as a first reference value (Db, Rb), and the first The characteristic value corresponding to the temperature of the battery possessed by the battery having deteriorated corresponding to the second reference time (te) after the reference time is defined as a second reference 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 (β, γ) that is information indicating the deterioration state of the battery;
The characteristic values (D2, R2 ), an estimating unit (32) for estimating
has
The deterioration information is information (β, γ) indicating a relationship between the characteristic value and the temperature of the battery in the deterioration state of the battery at the first point in time. The battery characteristics according to any one of claims 1 to 4 , wherein the rate of change of the first reference value with respect to temperature and the rate of change of the second reference value with respect to temperature are different from each other in at least a part of the temperature range. detection device.

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