Determination device, determination method, and determination program

Abstract

The purpose of the present invention is to accurately determine, with a simple configuration, whether or not a secondary battery (battery) corresponding to a use purpose is suitable. A determination device for determining, from among a plurality of batteries (1), a battery (1) suitable for a use purpose (4), the determination device being provided with: an information acquisition unit (12) for acquiring battery information (21) of the batteries (1); a deterioration estimation unit (14) that estimates, on the basis of the battery information (21), cause-by-cause deterioration information (6) indicating the deterioration state of each deterioration cause (7) for each battery (1); a use input unit (15) that receives an input of a use (4); and a determination unit (17) that, on the basis of the estimated cause-by-cause deterioration information (6) and the input use (4), determines a battery (1) suitable for the use (4) from among the plurality of batteries (1), taking into account the degree of influence of each deterioration cause (7) on the use (4).

Description

Technical Field

[0001] The present invention relates to a determination device, a determination method and a determination program for determining a battery suitable for use from a plurality of batteries. Background Art

[0002] Secondary batteries (batteries) are used in various devices such as electric vehicles. Devices equipped with secondary batteries are used for various purposes. Here, secondary batteries deteriorate with use, and the cause and rate of deterioration vary depending on the purpose of use (usage conditions). Therefore, when there are multiple such devices, the device to be used is sometimes selected based on the purpose of use of the device and the deterioration state of the secondary battery.

[0003] For example, in the invention described in Patent Document 1, the degradation tendency of the mounted high voltage device (secondary battery) is calculated based on the vehicle's travel distance, and a vehicle mounted with a high voltage device with a small degradation tendency is used in a management environment where degradation is predicted to increase.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2010-181986 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] However, in the previous structure, the degradation trend is only roughly calculated, and it is difficult to calculate the degradation state with high accuracy. In addition, in the previous structure, the vehicles with a small degradation trend are allocated in a management environment where it is predicted that the degradation will become larger, and it may not be possible to properly allocate vehicles corresponding to the predetermined management environment. In addition, it is also considered to select the secondary battery (equipment) to be used for each use purpose by predicting the future degradation state caused by use based on the use purpose, etc., but it is difficult to predict the degradation state with a simple structure, and it is also difficult to predict the degradation state with high accuracy.

[0009] In order to solve such a problem, an object of the present invention is to determine whether a secondary battery (battery) is suitable for a use purpose with high accuracy using a simple structure.

[0010] Solutions for solving problems

[0011] In order to achieve the above-mentioned purpose, the characteristic structure of the determination device involved in one embodiment of the present invention lies in the following point: a determination device for determining a battery suitable for a use purpose from a plurality of batteries, the determination device comprising: an information acquisition unit, which acquires battery information of the battery; a degradation estimation unit, which estimates, for each of the batteries, cause-based degradation information representing the degradation state of each degradation cause based on the battery information; a use input unit, which accepts input of the use purpose; and a determination unit, which determines the battery suitable for the use purpose from the plurality of batteries based on the estimated cause-based degradation information and the input use purpose, and taking into account the degree of influence of each of the degradation causes on the use purpose.

[0012] In addition, a characteristic structure of a determination method involved in one embodiment of the present invention lies in the following point: a determination method for determining a battery suitable for a use purpose from a plurality of batteries, the determination method comprising the following steps: obtaining battery information of the battery; estimating, for each of the batteries, cause-based degradation information indicating a degradation state of each degradation cause based on the battery information; accepting input of the use purpose; and determining, from the plurality of batteries, the battery suitable for the use purpose based on the estimated cause-based degradation information and the input use purpose, and taking into account the degree of influence of each of the degradation causes on the use purpose.

[0013] In addition, the characteristic structure of the determination program involved in one embodiment of the present invention lies in the following point: a determination program for determining a battery suitable for a use purpose from a plurality of batteries, the determination program causing a computer to perform the following functions: obtaining battery information of the battery; estimating, based on the battery information, cause-based degradation information indicating the degradation state of each degradation cause for each of the batteries; accepting input of the use purpose; and determining, based on the estimated cause-based degradation information and the input use purpose, the battery suitable for the use purpose from the plurality of batteries, taking into account the degree of influence of each of the degradation causes on the use purpose.

[0014] Batteries deteriorate due to various reasons. The battery deteriorates due to different degradation reasons depending on the usage conditions, that is, the usage purpose, and progresses at different speeds depending on the usage purpose. Therefore, if the usage purpose and the degradation information by cause indicating the degradation state of each degradation cause of the battery are known, the degree of influence on whether the battery is suitable for the usage purpose can be known.

[0015] According to the above configurations, by estimating the degradation information of each battery by cause, it is possible to determine whether each battery is suitable for the intended use without directly predicting the future degradation state of the battery. Therefore, it is possible to determine the battery suitable for the intended use with high accuracy using a simple configuration.

[0016] Furthermore, the cause-specific degradation information may include at least one of a cause-specific degradation state which is a degradation state for each of the degradation causes and a degradation rate which is a rate of progress of degradation for each of the degradation causes.

[0017] With such a structure, the degradation state of the battery can be determined with a high degree of freedom based on the battery information that can be obtained, and the battery suitable for the intended use can be determined with high accuracy. In addition, by using both the degradation state according to the cause and the degradation rate for determination, the degradation state of the battery can be determined with higher accuracy based on the current degradation state and degradation rate, and the battery suitable for the intended use can be determined with high accuracy.

[0018] Alternatively, the cause-based degradation state may be calculated based on a prior cause-based degradation state that is the cause-based degradation state before an arbitrary first time and a unit cause-based degradation state that degrades during the first time, and taking into account a time dependence that follows a power law relative to the elapsed time of the cause-based degradation state that differs depending on the degradation cause and the degradation rate that differs depending on the degradation cause and is determined according to the intended use.

[0019] With such a configuration, the degradation state according to the cause can be determined more accurately, and the degradation state of the battery can be determined more accurately, so that a battery suitable for the intended use can be determined more accurately.

[0020] In addition, it may also be provided with a storage unit, which stores a grade table generated for each of the intended uses, the grade table being divided into grades according to the values ​​of the cause-based degradation information corresponding to each of the degradation causes, the determination unit referring to the grade table corresponding to the input intended use, grades each of the batteries according to the cause-based degradation information estimated for each of the batteries, and determines the battery suitable for the intended use based on the grade.

[0021] The battery degradation state can be graded in advance according to the usage and the degradation information by cause. Moreover, according to the above structure, the battery suitable for the usage can be easily and accurately determined by referring to the grade table in which the grades are graded in advance.

[0022] In addition, it may also be provided with a storage unit, which stores determination conditions generated according to each of the intended uses, in which the relationship between each of the degradation causes and a value obtained by assigning a weight determined according to the degradation cause to the cause-based degradation information is set as a condition, and each condition is graded, and the determination unit refers to the determination conditions corresponding to the input intended use, grades each of the batteries according to the cause-based degradation information estimated for each of the batteries, and determines the battery suitable for the intended use according to the grade.

[0023] The battery degradation state can be graded according to the usage and the degradation information by cause, and the influence of the judgment condition on the battery degradation state corresponding to the usage. Moreover, according to the above structure, the battery suitable for the usage can be easily and accurately determined by referring to the judgment condition divided into grades in advance.

[0024] Furthermore, one of the batteries may be mounted on each of a plurality of electric vehicles, and the electric vehicle mounted with the battery selected based on the determination result of the determination unit may be selected as the electric vehicle suitable for the intended use.

[0025] With such a configuration, by selecting a battery suitable for the intended use, an electric vehicle suitable for the intended use can be easily and accurately selected.

[0026] Furthermore, the battery used for a predetermined first application may be reused as the battery for a second application different from the first application based on a determination result of the determination unit.

[0027] Even if a battery used for a certain purpose deteriorates, it can be reused (reused) for other purposes according to the deterioration state. For example, even if a battery mounted on an electric vehicle deteriorates, it can be reused as a stationary battery or a battery for other specific purposes according to the deterioration state.

[0028] According to the above configuration, it is possible to easily and accurately determine for what purpose the battery can be reused. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a diagram illustrating the concept of selecting an electric vehicle to be used from a plurality of electric vehicles according to the purpose of use.

[0030] Figure 2 This is a diagram illustrating the structure of a determination device.

[0031] Figure 3 This is a diagram illustrating a flow of battery determination.

[0032] Figure 4 This is a diagram illustrating an example of a level table.

[0033] Figure 5 This is a diagram illustrating an example of a level table taking into account the degradation rate.

[0034] Figure 6 It is a diagram illustrating determination conditions. DETAILED DESCRIPTION

[0035] Sometimes depending on the intended use4 (refer to Figure 2 ) from a plurality of secondary batteries (hereinafter referred to as battery 1 (refer to Figure 1 )) selects an appropriate battery 1. The determination device according to one embodiment of the present invention estimates each deterioration factor 7 representing each battery 1 (see Figure 1 ) of the degradation state according to the cause of degradation information 6 (refer to Figure 2 ), and considering the degree of influence of the deterioration cause 7 on the use purpose 4, a battery 1 suitable for the use purpose 4 is determined from multiple batteries 1.

[0036] The determination device is described below by taking as an example a structure in which a battery 1 suitable for the intended use 4 is determined from among a plurality of electric vehicles 2 equipped with one battery 1, and an electric vehicle 2 equipped with a battery 1 suitable for the intended use 4 is selected. Here, one battery 1 does not mean a single cell, but includes a battery pack composed of a plurality of cells and functioning as one battery 1 as a whole.

[0037] like Figure 1 As shown, a plurality of electric vehicles 2 equipped with batteries 1 are prepared, such as a vehicle 2a equipped with battery 1a, a vehicle 2b equipped with battery 1b, etc., and any electric vehicle 2 is assigned to each use purpose 4 such as use purpose 4α, use purpose 4β, etc. At this time, the cause-based degradation information 6 of each battery 1 is estimated, and the degree of influence of the degradation cause 7 of the cause-based degradation information 6 on the use purpose 4 is considered to determine the battery 1 suitable for the use purpose 4 from the plurality of batteries 1. Then, the electric vehicle 2 equipped with the battery 1 corresponding to the determination result is selected as the electric vehicle 2 used for each use purpose 4.

[0038] [Judgment device]

[0039] Next, use Figure 2 , Figure 3 An embodiment of a determination device for determining the battery 1 will be described.

[0040] The electric vehicle 2 is equipped with a secondary battery (battery 1 ) such as a lithium ion battery. Battery information 21 , which is various information of the battery 1 , is acquired by a measurement unit 23 .

[0041] The determination device includes an information acquisition unit 12 , a degradation estimation unit 14 , a usage input unit 15 , a determination unit 17 , and a storage unit 19 .

[0042] The information acquisition unit 12 acquires the battery information 21 of each battery 1 from the measurement unit 23, and stores the battery information 21 of each battery 1 in the storage unit 19 ( Figure 3 Step #1).

[0043] The degradation estimation unit 14 estimates the cause-based degradation information 6 for each battery 1 based on the battery information 21 of each battery 1 stored in the storage unit 19, and stores the cause-based degradation information 6 for each battery 1 in the storage unit 19 ( Figure 3 Step #2 of the above). The cause-based degradation information 6 is the estimated degradation state of each degradation cause 7. That is, the cause-based degradation information 6 of each battery 1 is information including the degradation state corresponding to the specified degradation cause 7, such as the degradation state corresponding to the degradation cause A (degradation cause 7) and the degradation state corresponding to the degradation cause B (degradation cause 7).

[0044] The purpose input unit 15 is a manual operation tool such as a keyboard or a selection switch, and receives manual operation (input) of the purpose of use 4 of the electric vehicle 2 and stores the purpose of use 4 in the storage unit 19 ( Figure 3 Step #3). In addition, the purpose input unit 15 is not limited to accepting operations, and may also be a structure that accepts the use purpose 4 through communication.

[0045] The determination unit 17 classifies each battery 1 for each use 4 by considering the degree of influence of the degradation cause 7 of the cause-based degradation information 6 on the use 4 ( Figure 3 Then, the determination unit 17 determines the battery 1 corresponding to the input application 4 based on the level of each battery 1 corresponding to the input application 4 ( Figure 3 Step #5) For example, the determination unit 17 selects a battery 1 that can be used for the input application 4, or selects a battery 1 that is most suitable for the input application 4.

[0046] [Battery determination]

[0047] Next, as a structural example for determining the battery 1, use Figure 1 , Figure 2 , Figure 4 A configuration is described in which the battery 1 is judged using the rank table 26 which is generated in advance in consideration of the degree of influence of the cause-specific degradation information 6 on the usage 4 for each degradation cause 7 and stored in the storage unit 19 .

[0048] In this embodiment, as the use purpose 4 of the electric vehicle 2, normal driving (use purpose I), driving in a high temperature environment (use purpose II), repeated large current charging (fast charging) and driving in a low temperature environment (use purpose III) are assumed.

[0049] In addition, as the cause-specific degradation information 6 of the battery 1, the cause-specific degradation state 8, which is the degradation state of each degradation cause 7, is estimated. Figure 4 In the example, as degradation cause 7, it is estimated that the degradation is caused by the growth of SEI film (resistance film at the electrode-electrolyte interface) (degradation cause A), the high-temperature degradation is mainly caused by the generation of gas at the positive electrode (degradation cause B), and the low-temperature degradation is mainly caused by the precipitation of metallic lithium (degradation cause C).

[0050] exist Figure 4 In the illustrated level table 26, the degradation state 8 by cause (degradation information by cause 6) related to the degradation cause A is represented as the degradation state by cause μA, the degradation state 8 by cause (degradation information by cause 6) related to the degradation cause B is represented as the degradation state by cause μB, and the degradation state 8 by cause (degradation information by cause 6) related to the degradation cause C is represented as the degradation state by cause μC. In addition, the degradation state 8 by cause (degradation information by cause 6) can be set to a numerical value that decreases from 1 as degradation progresses. In addition, the degradation cause 7 is not limited to three, and the degradation state 8 by cause corresponding to an arbitrary number of degradation causes 7 can also be estimated. For example, as the degradation cause 7, any combination of the above three causes, cracking of the electrode active material, and crystal phase change can also be used.

[0051] Furthermore, in the rank table 26 , ranks corresponding to the usage purposes 4 are set in advance based on the magnitudes (conditions) of the estimated cause-by-cause degradation states 8 (cause-by-cause degradation information 6 ) of the respective degradation causes 7 .

[0052] For example, the condition of level "1" in the application I is set to "μA<0.2 and μB<0.2 and μC<0.2 and μA+μB+μC<0.3". Level "1" is the most appropriate (highest) level for the application 4. In each application 4, the condition of level "2" is a condition for a state where degradation has progressed further than the condition of level "1", and the condition of level "3" is a condition that does not meet the conditions of levels "1" and "2". Since the application II is driving in a high temperature environment and the degradation cause B is high temperature and the degradation progresses, there are many cases where the degradation progresses rapidly. Therefore, in each level, the condition of the degradation state μB by cause is made stricter than the condition in the application I. In addition, metal lithium reacts with the electrolyte in the battery 1 at high temperature and generates self-heat, which may cause serious accidents such as fire in the worst case. Therefore, in each level of the application II, the condition of the degradation state μC by cause is also made stricter than the condition in the application I. Since the use application III is fast charging in a low temperature environment, considering the possibility of metal lithium precipitation on the negative electrode, the conditions of the degradation state μC by cause in each level are made stricter than those in the use application I. In addition, the levels are not limited to three levels, and can be set to any level.

[0053] The determination unit 17 first reads the cause-based degradation state 8 of each degradation cause 7 estimated by the degradation estimation unit 14 for each battery 1 and the input use purpose 4 from the storage unit 19. Then, the determination unit 17 compares the cause-based degradation state 8 of each battery 1 with the conditions of each level corresponding to the use purpose 4 of the same level table 26, and determines which level each battery 1 corresponds to. For example, in the case of selecting (determining) a battery 1 for driving in a high temperature environment (use II) as the use purpose 4, it is assumed that the cause-based degradation state μA of a certain battery 1 is estimated to be 0.10, the cause-based degradation state μB is estimated to be 0.15, and the cause-based degradation state μC is estimated to be 0.09. In this case, μA+μB+μC=0.34. When this result is compared with the conditions of the use purpose II of the level table 26, the level of the battery 1 is "2". Based on this point, the determination unit 17 determines the levels of all batteries 1 that are the objects of determination (selection). Thereafter, based on the ranks of the individual batteries 1 , the electric vehicle 2 equipped with the battery 1 belonging to the highest rank is selected as the electric vehicle 2 for the usage purpose 4 .

[0054] If the cause-based degradation state 8 (cause-based degradation information 6) and the intended use 4 of each battery 1 are known, it is possible to determine the suitability of each battery 1 for the intended use 4. Therefore, the rank table 26 can be used to classify the rank indicating the suitability of each battery 1 for each intended use 4 under the condition of each cause-based degradation state 8. Therefore, by using the rank table 26, the rank of each battery 1 can be easily and accurately determined based on the cause-based degradation state 8 and the intended use 4.

[0055] [Deterioration estimation]

[0056] The degradation state 8 (degradation state) by cause is any degradation state that causes degradation of capacity, increase in internal resistance, etc., and can be obtained and calculated by any method. Figure 2 A method of estimating the cause-based degradation state 8 (degradation state) will be described by way of example.

[0057] For example, the degradation of the battery 1 can be approximately represented by a power law relative to the time (elapsed time) from the start of use. That is, the degradation of the battery 1 has a time dependence that is proportional to the power law of time, and depends on the degradation rate 9 that is the rate of progression of the degradation of each degradation cause 7. This proportional relationship can represent the degradation rate coefficient as a constant and the time coefficient as a power exponent. In addition, the degradation rate 9 can be estimated according to the use purpose 4 for each degradation cause 7. Here, the degradation rate coefficient is a coefficient that depends on various use conditions (use purpose 4) such as the use environment, use method, and use form, and the time coefficient is a coefficient that represents the time dependence of the degradation state.

[0058] Specifically, the cause-based degradation state 8 of the battery 1 can be calculated based on the prior cause-based degradation state 28 acquired in advance and the unit cause-based degradation state which is the degradation state during the period from calculation (measurement) of the prior cause-based degradation state until an arbitrary first time has passed. That is, the cause-based degradation state 8 of the battery 1 at the current time point can be calculated based on the prior cause-based pre-degradation state 28 acquired at the time point that is the first time ahead of the current time point and the unit cause-based degradation state during the first time.

[0059] In this case, the cause-based degradation state 8 at the current time point (at the time of estimation) has a proportional relationship with the time coefficient as a power exponent, and therefore the cause-based degradation state 8 is calculated based on the prior cause-based degradation state 28 and the unit cause-based degradation state, and in consideration of the time dependence following the power law with respect to the elapsed time. That is, the cause-based degradation state 8 is calculated based on the prior cause-based degradation state 28 and the unit cause-based degradation state degraded during the first time, and in consideration of the time dependence following the power law with respect to the elapsed time of the cause-based degradation state 8 that differs depending on the degradation cause 7, and the degradation rate 9 that differs depending on the degradation cause 7 and is determined by the usage conditions (purpose of use 4) at the time of calculation (at the time of estimation). For example, when the time at the time of estimation is set to t, the first time is set to δ, the cause-based degradation state 8 at time t is set to μt, the prior cause-based degradation state 28 is set to μ(t-δ), the degradation rate coefficient is set to α, and the time coefficient is set to β, it is possible to use the method of

[0060] μt={μ(t-δ) 1 / β -α 1 / β ·δ} β (Formula 1)

[0061] The function represented by is evaluated.

[0062] As described above, the degradation estimation unit 14 can calculate (estimate) the cause-based degradation state 8 using the prior cause-based degradation state 28, and thus can calculate the cause-based degradation state 8 of the battery 1 with high accuracy. In particular, the prior cause-based degradation state 28 can be set to an actual measurement value or a predicted correction value corrected by taking the actual measurement value into consideration. In this case, since the actual prediction is reduced to the degradation state during the first time period, the cause-based degradation state 8 of the battery 1 can be calculated with higher accuracy.

[0063] [Other embodiments]

[0064] (1) In the above embodiment, the degradation of the battery 1 as it is used can be estimated not only from the cause-based degradation state 8 but also from the degradation rate 9 for each degradation cause 7. Therefore, the cause-based degradation information 6 may include at least one of the cause-based degradation state 8 and the degradation rate 9.

[0065] The information acquisition unit 12 acquires various battery information 21. The cause-based degradation information 6 that can be estimated may be different depending on the acquired battery information 21. Therefore, with respect to the cause-based degradation information 6, the degradation estimation unit 14 may estimate the degradation rate 9 of each degradation cause 7 based on the acquired battery information 21, even if it is difficult to estimate the cause-based degradation state 8. Moreover, the battery 1 can be determined based on the estimated cause-based degradation information 6. In this way, the degree of freedom of the cause-based degradation information 6 to be estimated can be increased, so that the degradation state of the battery 1 can be easily determined with a high degree of freedom, and the battery 1 suitable for the intended use 4 can be determined with high accuracy. In addition, when both the cause-based degradation state 8 and the degradation rate 9 are used for determination, the degradation state of the battery 1 can be estimated with higher accuracy, so that the battery 1 suitable for the intended use 4 can be determined with higher accuracy.

[0066] (2) When the conditions of the above-mentioned level table 26 are set based on the degradation rate 9, the conditions in each level may use the degradation state change amount 29 by cause, which is the amount of change in the degradation state per unit time that can be obtained based on the degradation rate 9 for each degradation cause 7. The degradation estimation unit 14 estimates the degradation state change amount 29 by cause for each battery 1 for each degradation cause 7 based on the battery information 21 of each battery 1. In addition, in the level table 26, the level corresponding to the use purpose 4 is set in advance based on the size (condition) of the estimated degradation state change amount 29 by cause (degradation information by cause 6) for each degradation cause 7, similarly to the level table 26 based on the above-mentioned degradation state by cause 8.

[0067] Thus, the degradation state of the battery 1 can be estimated with higher accuracy based on the degradation rate 9 , and the battery 1 suitable for the intended use 4 can be determined with higher accuracy.

[0068] Furthermore, the conditions of the rank table 26 may be determined based on the cause-specific degradation state 8 and the degradation rate 9 (the cause-specific degradation state change amount 29 ).

[0069] For example, when used at high temperatures, the growth of the SEI film (deterioration cause A) and the generation of gas on the positive electrode (deterioration cause B) are likely to progress. On the other hand, regarding the precipitation of metallic lithium (deterioration cause C), there is a concern that lithium has already precipitated and reacted at high temperatures (self-heating). Therefore, it is also possible to Figure 5 As shown, the conditions corresponding to the growth of the SEI film (deterioration cause A) and the generation of gas on the positive electrode (deterioration cause B) are mainly determined based on the degradation rate 9 (deterioration state change amount 29 by cause), and the conditions corresponding to the precipitation of metallic lithium (deterioration cause C) are determined based on the degradation state by cause 8. As a result, the battery 1 corresponding to the use purpose 4 can be more accurately operated.

[0070] In addition, Figure 5 , the cause-by-cause degradation state change amount 29 related to the degradation cause A is expressed as the cause-by-cause degradation state change amount ΔμA, the cause-by-cause degradation state change amount 29 related to the degradation cause B is expressed as the cause-by-cause degradation state change amount ΔμB, the cause-by-cause degradation state 8 related to the degradation cause A is expressed as the cause-by-cause degradation state μA, the cause-by-cause degradation state 8 related to the degradation cause B is expressed as the cause-by-cause degradation state μB, and the cause-by-cause degradation state 8 related to the degradation cause C is expressed as the cause-by-cause degradation state μC. In addition, in Figure 5 Only the conditions of each level related to one usage 4 are shown.

[0071] (3) In the above-mentioned embodiments, the rank table 26 may use as a condition a value obtained by assigning a weight determined according to the degradation cause 7 to each of the cause-specific degradation information 6. This allows the degradation state of the battery 1 to be estimated with higher accuracy, and thus allows the battery 1 suitable for the intended use 4 to be determined with high accuracy.

[0072] (4) In the above-mentioned embodiments, the determination unit 17 may determine the degradation state of the battery 1 by not only referring to the level table 26 but also determining the battery 1 suitable for the intended use 4 from among the plurality of batteries 1 by an arbitrary method taking into account the degree of influence of the degradation cause 7 on the intended use 4 .

[0073] For example, the determination unit 17 determines the rank of each battery 1 based on the cause-based degradation information 6 of each battery 1 estimated by the degradation estimation unit 14 for each degradation cause 7, based on the determination condition 31. In the determination condition 31, a relational expression (condition) set as a condition based on the cause-based degradation information 6 for each degradation cause 7 and a numerical range corresponding to the rank of the value derived from the relational expression are set in accordance with the use purpose 4. The determination condition 31 is predetermined and stored in the storage unit 19. As described above, the cause-based degradation information 6 is at least one of the cause-based degradation state 8 and the degradation speed 9. For example, the relational expression is the sum of the cause-based degradation information 6 for each degradation cause 7.

[0074] Furthermore, in the determination condition 31, a condition may be set in which a weight (weight coefficient) determined according to the degradation cause 7 is assigned to the relational expression. That is, in the determination condition 31, a relationship between a value obtained by assigning a weight determined according to the degradation cause 7 to the cause-based degradation information 6 is set as a condition, and each condition is classified into a level. In this way, it is possible to more easily and accurately determine a battery 1 suitable for the intended use 4.

[0075] For example, Figure 6As shown, when the cause-based degradation state 8 (cause-based degradation information 6) related to the degradation cause A is set to the cause-based degradation state μA, the cause-based degradation state 8 (cause-based degradation information 6) related to the degradation cause B is set to the cause-based degradation state μB, the cause-based degradation state 8 (cause-based degradation information 6) related to the degradation cause C is set to the cause-based degradation state μC, the weight coefficient related to the degradation cause A is set to WA, the weight coefficient related to the degradation cause B is set to WB, the weight coefficient related to the degradation cause C is set to WC, and the relational expression is set to X, the relational expression is expressed as

[0076] X = WA × μA + WB × μB + WC × μC (Formula 2).

[0077] Then, a weight coefficient is set for each intended use 4. For example, the weight coefficient in (intended use I) is set to WA=WB=WC=1.0, the weight coefficient in (intended use II) is set to WA=1.0, WB=2.0, WC=2.0, and the weight coefficient in (intended use III) is set to WA=1.0, WB=1.0, WC=3.0. In this way, the weight coefficient is set according to the intended use 4, and each battery 1 can be graded simply by substituting the weight coefficient into the relational expression. Compared with the case of grading using the grade table 26, etc., it is possible to easily determine the battery 1 suitable for the intended use 4 with a simple structure.

[0078] In addition, the numerical range corresponding to level "1" is set to 0.0≤X<0.2, the numerical range corresponding to level "2" is set to 0.2≤X<0.5, and the numerical range corresponding to level "3" is set to 0.5≤X.

[0079] The determination unit 17 first reads the degradation state 8 by cause of each degradation cause 7 estimated by the degradation estimation unit 14 for each battery 1 and the input use purpose 4 from the storage unit 19. Next, the determination unit 17 determines the weight coefficient corresponding to the use purpose 4. Next, the determination unit 17 substitutes the degradation state 8 by cause of each battery 1 and the weight coefficient into the relationship to obtain the value of X. Then, the determination unit 17 determines to which numerical range the value of X belongs, and determines the rank of each battery 1. Thereafter, based on the rank of each battery 1, the battery 1 (electric vehicle 2) used for the use purpose 4 is selected.

[0080] (5) In the above-mentioned other embodiment (4), similarly to the other embodiment (2), the cause-based degradation state change amount 29 (degradation speed 9) may be further considered. In this case, in addition to the cause-based degradation state 8 for each degradation cause 7, the cause-based degradation state change amount 29 for each degradation cause 7 is also considered to set the relational expression.

[0081] For example, when the cause-by-cause degradation state change amount 29 related to the degradation cause A is set to the cause-by-cause degradation state change amount ΔμA, the cause-by-cause degradation state change amount 29 related to the degradation cause B is set to the cause-by-cause degradation state change amount ΔμB, the cause-by-cause degradation state change amount 29 related to the degradation cause C is set to the cause-by-cause degradation state change amount ΔμC, the weight coefficient of the cause-by-cause degradation state 8 related to the degradation cause A is set to WA1, the weight coefficient of the cause-by-cause degradation state 8 related to the degradation cause B is set to WB1, the weight coefficient of the cause-by-cause degradation state 8 related to the degradation cause C is set to WC1, the weight coefficient of the cause-by-cause degradation state change amount 29 related to the degradation cause A is set to WA2, the weight coefficient of the cause-by-cause degradation state change amount 29 related to the degradation cause B is set to WB2, the weight coefficient of the cause-by-cause degradation state change amount 29 related to the degradation cause C is set to WC2, and the relational expression is set to X, the relational expression in the determination condition 31 is expressed as

[0082] X=WA1×μA+WA2×△μA+WB1×μB+WB2×△uB+WC1×μC+WC2×△μC (Formula 3).

[0083] In the determination condition 31 , in such a relational expression, a weight coefficient of the cause-based degradation state 8 and a weight coefficient of the cause-based degradation state change amount 29 are set for each usage purpose 4 , and a condition of the relational expression for each level is set.

[0084] The determination unit 17 considers such a cause-based degradation state change amount 29 (degradation rate 9) and determines each battery 1 based on the determination condition 31. Thus, the battery 1 is determined by considering the degradation rate 9 in addition to the degradation state (cause-based degradation state 8), so that the battery 1 suitable for the intended use 4 can be determined with higher accuracy.

[0085] (6) In the above-described embodiments, the determination device is not limited to determination of the battery 1 mounted on the electric vehicle 2, but can be used for determination of the battery 1 for all purposes.

[0086] Specifically, a battery 1 used for a certain purpose is sometimes no longer suitable for the purpose due to the deterioration caused by the use. However, even such a battery 1 can sometimes be reused (reused) as a battery 1 for other purposes where the use conditions are not strict. Whether it can be reused in this way and the purpose for which it can be reused can be judged based on the current deterioration state of the battery 1. Moreover, the current deterioration state of the battery 1 can be judged by the judgment device in each of the above-mentioned embodiments. In this case, the judgment unit 17 judges each battery 1 using conditions that are graded according to the purpose of use 4 (usage conditions) to be reused. According to the judgment result of the judgment unit 17, the battery 1 is reused as a battery 1 used in a purpose different from the purpose used before it became the current state.

[0087] For example, the battery 1 mounted on the electric vehicle 2 requires strict usage conditions because the driving location and driving mode are not always fixed. Therefore, even if the battery 1 deteriorates to the point where it is not suitable as a battery 1 mounted on the electric vehicle 2 (equivalent to the first use), it can be reused as a battery 1 used in a state of being set in a specified location (fixed battery, equivalent to the second use) or a battery 1 for other specific uses with relatively stable usage conditions (equivalent to the second use). In addition, if the deterioration state of the battery 1 is significantly worsened, it can also be considered to abandon reuse and recycle the battery 1.

[0088] Therefore, as the usage purposes 4, the conditions for ranking corresponding to the fixed battery, the battery 1 for one or more other purposes, and the recycling are assigned, and the determination unit 17 determines each battery 1 expected to be reused based on the conditions corresponding to the ranking. Then, the reuse destination of each battery 1 is determined based on the determination result. In this way, the reuse destination of the battery 1 can be easily determined.

[0089] (7) In the above-mentioned embodiments, the determination device is not limited to Figure 2 The device composed of the functional blocks shown can also be composed of arbitrary functional blocks. For example, the functional blocks of the determination device can be further subdivided, and conversely, part or all of the functional blocks can be combined. In addition, the function of the determination device is not limited to the above-mentioned functional blocks, and can also be implemented by a method executed by an arbitrary functional block. In addition, part or all of the determination device can also be composed of software. Programs related to the software are stored in an arbitrary storage device such as the storage unit 19, and are executed by a processor (computer) such as a CPU possessed by the determination device or a processor (computer) disposed separately. For example, part or all of the processing of the program can also be executed by a processor mounted on a device such as a server that is disposed separately from the determination device.

[0090] In addition, the structure disclosed in the above-mentioned embodiment (including other embodiments, the same below) can be combined and applied with the structure disclosed in other embodiments as long as no contradiction occurs. In addition, the embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited to these and can be appropriately changed within the scope of the purpose of the present invention.

[0091] Industrial Applicability

[0092] The present invention can be applied to a determination device for determining the degradation state of a battery.

[0093] Description of Reference Numerals

[0094] 1: Battery; 2: Electric vehicle; 4: Purpose of use; 6: Degradation information by cause; 7: Degradation cause; 8: Degradation status by cause; 9: Degradation speed; 12: Information acquisition unit; 14: Degradation estimation unit; 15: Purpose input unit; 17: Judgment unit; 19: Storage unit; 21: Battery information; 23: Measurement unit; 26: Level table; 28: Prior degradation status by cause; 31: Judgment condition.

Claims

1. A determination device for determining a battery suitable for a use purpose from a plurality of batteries, the determination device comprising: an information acquisition unit, configured to acquire battery information of the battery; a degradation estimating unit that estimates, for each of the batteries, cause-specific degradation information indicating a degradation state for each degradation cause based on the battery information; a purpose input unit for accepting input of the purpose of use; as well as A determination unit determines the battery suitable for the intended use from among the plurality of batteries, based on the estimated cause-based deterioration information and the input intended use, and taking into account the degree of influence of each of the deterioration causes on the intended use.

2. The determination device according to claim 1, wherein: The cause-based degradation information includes at least any one of a cause-based degradation state which is a degradation state for each of the degradation causes and a degradation rate which is a rate of progress of degradation for each of the degradation causes.

3. The determination device according to claim 2, wherein: The cause-based degradation state is calculated based on the prior cause-based degradation state which is the cause-based degradation state before an arbitrary first time and the unit cause-based degradation state which degraded during the first time, and taking into account the time dependence following a power law with respect to the elapsed time of the cause-based degradation state which differs depending on the degradation cause and the degradation rate which differs depending on the degradation cause and is determined according to the intended use.

4. The determination device according to any one of claims 1 to 3, wherein: further comprising a storage unit storing a grade table generated for each of the usage purposes; The ranking table is divided into levels according to the values ​​of the cause-based degradation information corresponding to the respective causes of degradation, The determination unit refers to the rank table corresponding to the input intended use, classifies each of the batteries according to the cause-based deterioration information estimated for each of the batteries, and determines the battery suitable for the intended use based on the rank.

5. The determination device according to any one of claims 1 to 3, wherein: further comprising a storage unit for storing the determination conditions generated for each of the usage purposes, In the determination condition, the relationship between each of the degradation causes and a value obtained by assigning a weight determined according to the degradation cause to the cause-specific degradation information is set as a condition, and each condition is classified into a level, The determination unit refers to the determination condition corresponding to the input intended use, classifies the batteries according to the cause-based deterioration information estimated for the batteries, and determines the battery suitable for the intended use according to the class.

6. The determination device according to any one of claims 1 to 3, wherein: Each of a plurality of electric vehicles is equipped with a battery. The electric vehicle equipped with the battery selected based on the determination result of the determination unit is selected as the electric vehicle suitable for the intended use.

7. The determination device according to any one of claims 1 to 3, wherein: The battery used in a predetermined first application is reused as the battery used in a second application different from the first application based on a determination result of the determination unit.

8. A method for determining a battery suitable for a use purpose from among a plurality of batteries, the method comprising the following steps: Obtaining battery information of the battery; estimating, for each of the batteries, cause-specific degradation information indicating a degradation state for each degradation cause based on the battery information; Accepting input of the stated purpose of use; as well as Based on the estimated cause-based deterioration information and the input application, the battery suitable for the application is determined from among the plurality of batteries in consideration of the degree of influence of each of the deterioration causes on the application.

9. A determination program for determining a battery suitable for a use purpose from among a plurality of batteries, the determination program causing a computer to execute the following functions: Obtaining battery information of the battery; estimating, for each of the batteries, cause-specific degradation information indicating a degradation state for each degradation cause based on the battery information; Accepting input of the intended use; and Based on the estimated cause-based degradation information and the input intended use, and taking into account the degree of influence of each of the degradation causes on the intended use, the battery suitable for the intended use is determined from among the plurality of batteries.

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