Battery Evaluation System

Abstract

To provide a battery evaluation system which can precisely evaluate a secondary battery.SOLUTION: A battery evaluation system comprises: a reception unit which receives information about a secondary battery to be evaluated; an extraction unit which extracts the information about a plurality of evaluation items, from the received information about the secondary battery; an evaluation unit which evaluates each of the information about the plurality of extracted evaluation items, and performs total evaluation about the secondary battery on the basis of a plurality of evaluation results and a plurality of weighting factors corresponding to the plurality of evaluation results; and an output unit which at least outputs a result of the total evaluation about the secondary battery. The plurality of evaluation items include at least the evaluation item about temperature frequency distribution from a use start point of the secondary battery to an evaluation time point. The evaluation unit evaluates the temperature frequency distribution of the secondary battery, on the basis of a deviation degree from reference temperature frequency distribution in the temperature frequency distribution of the secondary battery.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a battery evaluation system. [Background technology]

[0002] In recent years, there has been a demand for accurate evaluation of secondary batteries such as lithium-ion batteries. For example, Patent Document 1 discloses a presentation device that derives the relative degree of deterioration of a secondary battery installed in a target vehicle and presents the result to the user of the target vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 045033 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, the evaluation items for secondary batteries do not include, for example, evaluation items regarding the temperature frequency distribution from the start of use of the secondary battery to the evaluation time. Therefore, in Patent Document 1, there is a possibility that two secondary batteries with the same average temperature from the start of use to the evaluation time will be evaluated as having the same value, even though the variations in the temperature frequency distribution from the start of use to the evaluation time are different. In other words, Patent Document 1 has the problem of not being able to accurately evaluate secondary batteries.

[0005] The present disclosure has been made in view of the above background, and has an object to provide a battery evaluation system that can accurately evaluate secondary batteries. [Means for solving the problem]

[0006] A battery evaluation system according to the present disclosure includes a receiving unit that receives information about a secondary battery to be evaluated, an extracting unit that extracts information about a plurality of evaluation items from the received information about the secondary battery, an evaluating unit that evaluates each of the extracted information about the plurality of evaluation items and performs an overall evaluation of the secondary battery based on a plurality of evaluation results and a plurality of weighting factors corresponding to the plurality of evaluation results, and an output unit that outputs at least the result of the overall evaluation of the secondary battery, wherein the plurality of evaluation items include at least an evaluation item about a temperature frequency distribution of the secondary battery from the start of use to the evaluation time, and the evaluating unit evaluates the temperature frequency distribution of the secondary battery based on the degree of deviation of the temperature frequency distribution of the secondary battery from a reference temperature frequency distribution. Because this battery evaluation system includes an evaluation item about the temperature frequency distribution of the secondary battery as an evaluation item for the secondary battery, it is possible to evaluate the secondary battery more accurately. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to provide a battery evaluation system capable of evaluating secondary batteries with high accuracy. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a configuration example of a battery evaluation system according to a first embodiment. [Figure 2] 2 is a flowchart showing the operation of a battery evaluation device provided in the battery evaluation system shown in FIG. [Figure 3] 3 is a flowchart showing a flow of evaluation of information relating to a plurality of evaluation items of a secondary battery by a battery evaluation device provided in the battery evaluation system shown in FIG. [Figure 4] FIG. 10 is a diagram showing a frequency distribution of remaining capacity for a plurality of secondary batteries having the same elapsed age. [Figure 5] FIG. 10 is a diagram showing a frequency distribution of the temperature of the secondary battery to be evaluated from the start of use to the time of evaluation. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described below through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential means for solving the problems. For clarity of explanation, the following description and drawings have been omitted and simplified as appropriate. In each drawing, the same elements are given the same reference numerals, and duplicate explanations are omitted as necessary.

[0010] <First Embodiment> FIG. 1 is a diagram showing an example of the configuration of a battery evaluation system 1 according to a first embodiment. The battery evaluation system 1 is a system for evaluating the value of a rechargeable secondary battery (battery) such as a lithium ion battery. Here, the battery evaluation system 1 can evaluate the secondary battery more accurately by including an evaluation item regarding the temperature frequency distribution of the secondary battery in the evaluation items of the secondary battery. This will be specifically described below.

[0011] 1, the battery evaluation system 1 includes a battery evaluation device 10, a secondary battery 21 mounted on a vehicle 20, and a network 50. The battery evaluation device 10 can also be referred to as a battery evaluation system by itself. The battery evaluation device 10 and the vehicle 20 (or the secondary battery 21) are configured to be able to communicate with each other via the wired or wireless network 50.

[0012] In the present embodiment, the battery evaluation device 10 is described taking as an example a case where it evaluates a secondary battery 21 mounted on a vehicle 20, but is not limited thereto, and it may also evaluate a secondary battery 21 mounted on an object other than the vehicle 20. For example, the battery evaluation device 10 may evaluate a secondary battery 21 mounted on a mobile terminal such as a smartphone. In addition, the battery evaluation device 10 is described taking as an example a case where it evaluates a secondary battery 21 via a network 50, but is not limited thereto, and it may also evaluate a secondary battery 21 directly without via the network 50.

[0013] The battery evaluation device 10 is a device that evaluates the value of a secondary battery 21. Specifically, the battery evaluation device 10 includes a receiving unit 11, an extracting unit 12, an evaluating unit 13, and an output unit 14.

[0014] First, the receiving unit 11 receives information about the secondary battery 21 to be evaluated. The information about the secondary battery 21 includes information about the usage status and usage environment of the secondary battery 21, and includes at least, for example, the number of years elapsed, the remaining capacity, the average temperature during period T1, where T1 is the period from the start of use of the secondary battery 21 to the evaluation time point, and the temperature frequency distribution during period T1. Here, the number of years elapsed of the secondary battery 21 refers to the period from the start of use of the secondary battery 21 to the evaluation time point (i.e., period T1). The remaining capacity of the secondary battery 21 refers to the ratio of the full charge capacity of the secondary battery 21 at the time of evaluation to the full charge capacity of the secondary battery 21 before use.

[0015] In addition, the information about the secondary battery 21 may include the average SOC (State Of Charge) for the period T1, the SOC frequency distribution for the period T1, the average charged amount of electricity for the period T1, the frequency distribution of the charged amount of electricity for the period T1, the average discharged amount of electricity for the period T1, the frequency distribution of the discharged amount of electricity for the period T1, the average value of the voltage differences between each of the multiple battery cells that make up the secondary battery 21, and the frequency distribution of the voltage differences between each of the multiple battery cells that make up the secondary battery 21.

[0016] Information about the secondary battery 21 is observed by an observation device provided separately from the secondary battery 21, or by the observation function if the secondary battery 21 is equipped with such a function, and is stored in a storage device (not shown). Then, the receiving unit 11 of the battery evaluation device 10 receives the information about the secondary battery 21 stored in the storage device.

[0017] The extraction unit 12 extracts information relating to a plurality of evaluation items from the information relating to the secondary battery 21 received by the receiving unit 11. In other words, the extraction unit 12 classifies the information relating to the secondary battery 21 received by the receiving unit 11 into one of the plurality of evaluation items. The information relating to the plurality of evaluation items corresponds to information relating to the usage status and usage environment of the secondary battery 21.

[0018] The evaluation unit 13 evaluates each piece of information relating to the multiple evaluation items extracted by the extraction unit 12. For example, the evaluation unit 13 evaluates the temperature frequency distribution of the secondary battery 21 based on the degree of deviation of the temperature frequency distribution of the secondary battery 21 from a reference temperature frequency distribution (for example, an average temperature frequency distribution in the market). Then, the evaluation unit 13 performs a comprehensive evaluation of the secondary battery 21 based on multiple evaluation results and multiple weighting coefficients corresponding to the multiple evaluation results. The evaluation method used by the evaluation unit 13 will be described in detail later.

[0019] The output unit 14 outputs the result of the overall evaluation of the secondary battery 21. The result of the overall evaluation output from the output unit 14 is, for example, displayed on a monitor of a user terminal of a user who owns the secondary battery 21, or notified to the user terminal. Alternatively, the result of the overall evaluation output from the output unit 14 may be displayed on a monitor provided in the battery evaluation device 10.

[0020] The output unit 14 may further output the evaluation results for each evaluation item of the secondary battery 21. This allows the user to identify a secondary battery 21 that has a high overall evaluation but a low evaluation for a specific item, for example.

[0021] Next, the operation of the battery evaluation device 10 will be described with reference to Fig. 2. Fig. 2 is a flowchart showing the operation of the battery evaluation device 10.

[0022] First, the battery evaluation device 10 receives information about the secondary battery 21 to be evaluated (step S101). Then, the battery evaluation device 10 extracts information about a plurality of evaluation items from the received information about the secondary battery 21 (step S102). In other words, the battery evaluation device 10 classifies the received information about the secondary battery 21 into one of a plurality of evaluation items. Then, the battery evaluation device 10 evaluates each of the extracted information about the plurality of evaluation items (step S103). For example, the evaluation unit 13 evaluates the temperature frequency distribution of the secondary battery 21 based on the degree of deviation of the temperature frequency distribution of the secondary battery 21 from a reference temperature frequency distribution (e.g., an average temperature frequency distribution in the market). Then, the battery evaluation device 10 performs a comprehensive evaluation of the secondary battery 21 based on a plurality of evaluation results and a plurality of weighting factors corresponding to the plurality of evaluation results (step S104). Then, the battery evaluation device 10 outputs the result of the comprehensive evaluation of the secondary battery 21 (step S105).

[0023] 3 is a flowchart showing the flow of evaluation of information relating to a plurality of evaluation items of the secondary battery 21 by the battery evaluation device 10. The flowchart shown in FIG. 3 corresponds to the processing of steps S102 to S104 in FIG.

[0024] 3, the battery evaluation device 10 extracts information P1 to Pm relating to m (m is an integer equal to or greater than 2) evaluation items from the received information about the secondary battery 21 (step S201). Hereinafter, the information P1 to Pm relating to the evaluation items will also be referred to as data P1 to Pm. Then, the value 1 is substituted for the variable j (step S202). Then, the battery evaluation device 10 determines whether the data Pj (i.e., data P1) is a scalar value (step S203).

[0025] For example, if the data Pj is a scalar value (YES in step S203), the battery evaluation device 10 converts the data Pj into an evaluation value (for example, a deviation value in the market) that indicates the position of the data Pj in the data group (step S204). Then, the battery evaluation device 10 stores the converted value (relative value) of the data Pj and the absolute value of the data Pj as evaluation values ​​of the data Pj (step S207).

[0026] Here, data Pj expressed by a scalar value refers to data that can be expressed by a single numerical value, such as the number of years elapsed or the remaining capacity. For example, if data Pj represents a remaining capacity of "90%, " the battery evaluation device 10 stores the absolute value of the remaining capacity, "90%, " and the deviation value (relative value) of the remaining capacity of data Pj relative to the remaining capacities of multiple secondary batteries that have the same elapsed age, as evaluation values ​​for data Pj. In the example of Fig. 4, secondary battery A, which is five years old and has a remaining capacity of 90%, has an average remaining capacity compared to the multiple secondary batteries that have the same elapsed age, and therefore exhibits a medium deviation value of 50. Secondary battery B, which is three years old and has a remaining capacity of 90%, has a low remaining capacity compared to the multiple secondary batteries that have the same elapsed age, and therefore exhibits a low deviation value of 15.

[0027] On the other hand, if the data Pj is not a scalar value (NO in step S203), the battery evaluation device 10 compares the data Pj with reference data (for example, market average) and calculates a numerical value representing the comparison result (step S205).

[0028] Here, the data Pj that is not a scalar value refers to data that cannot be expressed by a single numerical value (in other words, data that is expressed by multiple numerical values), such as a temperature frequency distribution. For example, when the data Pj is data that represents a temperature frequency distribution for a period T1, the battery evaluation device 10 calculates a comparison value according to the degree of deviation of the temperature frequency distribution of the secondary battery 21 from a reference temperature frequency distribution (an average temperature frequency distribution on the market). Thereafter, the battery evaluation device 10 converts the calculated comparison value into a value (deviation value) that indicates its position in the data group (step S206), and saves the absolute value of the calculated comparison value (e.g., the average value (average temperature) for the period T1) as evaluation values ​​for the data Pj (step S207).

[0029] 5, the degree of deviation between the temperature frequency distribution (solid line) of secondary battery A and the reference temperature frequency distribution (dashed line) is small, so secondary battery A shows a medium deviation value of 50, while the degree of deviation between the temperature frequency distribution (solid line) of secondary battery B and the reference temperature frequency distribution (dashed line) is large, so secondary battery B shows a low deviation value of 25. In addition, the average temperatures of secondary batteries A and B for period T1 are both 20 degrees.

[0030] When data Pj is represented by a plurality of numerical values, the correlation (degree of deviation) r between data Pj and reference data is calculated, for example, by the following formula (1): where n represents the number of numerical values ​​constituting data Pj, xi represents the i-th numerical value among the n numerical values ​​constituting data Pj, and yi represents the i-th numerical value among the n numerical values ​​constituting reference data. TIFF0007779301000001.tif5105

[0031]

number

[0032] After that, when j < m (YES in step S208), after the value of j is incremented by 1 (step S209), the processes of steps S203 to 207 are repeated. That is, the process for the data P2 is performed. When j is no longer less than m (NO in step S208), that is, when j = m, the battery evaluation device 10 performs a comprehensive evaluation of the secondary battery 21 using the plurality of stored evaluation values (step S210).

[0033] The comprehensive evaluation value is calculated, for example, by the following formula (2). Here, wi represents the weighting coefficient for the evaluation value i, Xi represents the value of the evaluation value i, and f(Xi) represents a function of Xi.

[0034] Comprehensive evaluation value = Σwi × f(Xi) + constant ···(2)

[0035] For example, in the case of secondary battery A, X1 = remaining capacity 90%, X2 = deviation value of remaining capacity 50, X3 = average elapsed temperature 20°C, X4 = deviation value of temperature frequency distribution 50. Therefore, the comprehensive evaluation value of secondary battery A is expressed as follows.

[0036] Comprehensive evaluation value of secondary battery A ​​​​​​​​​​​​​​​​​ =84.5

[0039] That is, the battery evaluation device 10 evaluates the secondary battery A higher than the secondary battery B.

[0040] In this way, the battery evaluation system according to this embodiment can evaluate secondary batteries more accurately by including an evaluation item regarding the temperature frequency distribution of the secondary battery in the evaluation items of the secondary battery.

[0041] Furthermore, the present disclosure can be realized by causing a CPU (Central Processing Unit) to execute a computer program for all or part of the processing of the battery evaluation device 10.

[0042] The above-described program includes a set of instructions (or software code) that, when loaded into a computer, causes the computer to perform one or more functions described in the embodiments. The program may be stored in a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable media or tangible storage media include random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drives (SSD) or other memory technologies, CD-ROMs, digital versatile discs (DVDs), Blu-ray discs or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices. The program may also be transmitted on a transitory computer-readable medium or a communication medium. By way of example and not limitation, transitory computer-readable media or communication media include electrical, optical, acoustic, or other forms of propagated signals.

[0043] A part or all of the above-described embodiments can be described as, but not limited to, the following supplementary notes.

[0044] (Appendix 1) Battery evaluation system receiving information about a secondary battery to be evaluated; extracting information relating to a plurality of evaluation items from the received information relating to the secondary battery; evaluating each of the extracted information regarding the plurality of evaluation items, and performing a comprehensive evaluation of the secondary battery based on the plurality of evaluation results and a plurality of weighting factors corresponding to the plurality of evaluation results; outputting at least a result of a comprehensive evaluation of the secondary battery; A battery evaluation method, comprising: the plurality of evaluation items include at least an evaluation item regarding a temperature frequency distribution from the start of use of the secondary battery to the evaluation time, In the comprehensive evaluation of the secondary battery, the temperature frequency distribution of the secondary battery is evaluated based on the degree of deviation of the temperature frequency distribution of the secondary battery from a reference temperature frequency distribution. Battery evaluation method.

[0045] (Appendix 2) receiving information about a secondary battery to be evaluated; extracting information relating to a plurality of evaluation items from the received information relating to the secondary battery; a process of evaluating each of the extracted information regarding the plurality of evaluation items and performing a comprehensive evaluation of the secondary battery based on the plurality of evaluation results and a plurality of weighting factors corresponding to the plurality of evaluation results; a process of outputting at least a result of a comprehensive evaluation of the secondary battery; A control program for causing a computer to execute the above, the plurality of evaluation items include at least an evaluation item regarding a temperature frequency distribution from the start of use of the secondary battery to the evaluation time, the process of making a comprehensive evaluation of the secondary battery includes evaluating the temperature frequency distribution of the secondary battery based on a degree of deviation of the temperature frequency distribution of the secondary battery from a reference temperature frequency distribution. Control program. [Explanation of symbols]

[0046] 1 Battery evaluation system 10 Battery evaluation equipment 11 Receiving unit 12 Extraction part 13 Evaluation Section 14 Output section 20 vehicles 21 Secondary battery 50 Network

Claims

1. a receiving unit that receives information about a secondary battery to be evaluated; an extraction unit that extracts information about a plurality of evaluation items from the received information about the secondary battery; an evaluation unit that evaluates each of the extracted information regarding the plurality of evaluation items and performs a comprehensive evaluation of the secondary battery based on the plurality of evaluation results and a plurality of weighting factors corresponding to the plurality of evaluation results; an output unit that outputs at least a result of a comprehensive evaluation of the secondary battery; A battery evaluation system comprising: the plurality of evaluation items include at least an evaluation item regarding a temperature frequency distribution from the start of use of the secondary battery to the evaluation time, the evaluation unit evaluates the temperature frequency distribution of the secondary battery based on a degree of deviation of the temperature frequency distribution of the secondary battery from an average temperature frequency distribution in the market. Battery rating system.

2. The plurality of evaluation items include at least an evaluation item regarding the capacity of the secondary battery. The battery evaluation system according to claim 1 .

3. The plurality of evaluation items include at least an evaluation item regarding the elapsed time from the start of use of the secondary battery to the evaluation point. The battery evaluation system according to claim 1 .

4. The plurality of evaluation items include at least an evaluation item regarding an average temperature from the start of use of the secondary battery to the evaluation point. The battery evaluation system according to claim 1 .

5. the evaluation unit multiplies each of the plurality of evaluation results by the plurality of weighting coefficients corresponding to the plurality of evaluation results, and then adds up the multiplication results to calculate a comprehensive evaluation of the secondary battery. The battery evaluation system according to claim 1 .

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