Secondary battery diagnostic apparatus and method, battery pack including the apparatus, and vehicle

Abstract

Disclosed is a secondary battery diagnosis device capable of effectively diagnosing a state of a secondary battery using a charge / discharge signal extracted from the secondary battery. The secondary battery diagnosis device according to one aspect of the present invention includes a storage unit for storing a positive electrode reference curve and a negative electrode reference curve for charging or discharging of a reference battery, a voltage measurement unit configured to measure a voltage of a target battery during a charging or discharging process, and a processor configured to generate a plurality of charge / discharge measurement curves based on the voltage measured by the voltage measurement unit at a plurality of different time points, and compare each of the generated plurality of charge / discharge measurement curves with an analog curve obtained from the positive electrode reference curve and the negative electrode reference curve stored in the storage unit in order to determine a positive electrode adjustment curve and a negative electrode adjustment curve for each of the plurality of charge / discharge measurement curves such that an error between each of the charge / discharge measurement curves and the analog curve is within a certain level.

Description

TECHNICAL FIELD

[0001] This application claims priority to Korean Patent Application No. 10-2020-0185312, filed on December 28, 2020, in the Republic of Korea, the disclosure of which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to a secondary battery diagnosis technology, and more particularly, to a battery diagnosis technology capable of effectively diagnosing a secondary battery state using a charging and discharging signal of the secondary battery. BACKGROUND

[0003] Currently marketed secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, lithium secondary batteries, and the like. Among them, lithium secondary batteries are attracting attention because they have substantially no memory effect in addition to a very low discharge rate and a high energy density compared to nickel-based secondary batteries.

[0004] In addition, in recent years, secondary batteries have been widely used for driving or energy storage in medium- and large-sized devices such as electric vehicles or energy storage systems (ESS). In addition, for this reason, interest in secondary batteries is further increasing, and related research and development are being more actively conducted.

[0005] Lithium secondary batteries mainly use lithium-based oxides and carbon materials as positive active materials and negative active materials, respectively. In addition, the lithium secondary battery includes an electrode assembly in which a positive plate and a negative plate coated with a positive active material and a negative active material, respectively, are arranged with a separator interposed therebetween, and a case (i.e., a battery case) for airtightly accommodating the electrode assembly together with an electrolyte.

[0006] A secondary battery (i.e., a battery) generates electric energy through electrochemical oxidation and reduction reactions. However, when a charge / discharge cycle is repeated, the secondary battery does not maintain the capacity at the time of initial manufacturing (i.e., performance at the BOL (beginning of life) state), and can deteriorate over time. If the deterioration state of the secondary battery is not properly understood, it can be difficult to accurately predict the state of charge (SOC) of the battery, the available time, the lifespan, the timing of replacement, and the like. In addition, if prediction is not accurately made in this regard, this can cause unexpected damage to the user or manager of the secondary battery.

[0007] In addition, in the manufacturing process of the secondary battery, there can be a defective battery. For example, among many manufactured batteries, there can be a secondary battery that does not have a capacity at the time of design or a use area due to a process error.

[0008] In this regard, various techniques for diagnosing a secondary battery state during use of the secondary battery, particularly, according to a state change of a deteriorated secondary battery, have been proposed. However, in the case of the diagnostic techniques proposed thus far, there are a number of problems such as a relatively complex calculation method or low accuracy. Therefore, there is still a need for a more simple and more accurate efficient secondary battery diagnostic technique. SUMMARY

[0009] TECHNICAL PROBLEM

[0010] The present disclosure is designed to solve the problems of the related art, and thus, the present disclosure relates to a secondary battery diagnostic apparatus and method that can diagnose a state of a secondary battery using charge and discharge signals extracted from the secondary battery, and a battery pack including the diagnostic apparatus.

[0011] These and other objects and advantages of the present disclosure can be understood from the following detailed description, and will be more fully apparent from the exemplary embodiments of the present disclosure. Furthermore, it will be readily understood that the objects and advantages of the present disclosure can be achieved by the devices shown in the claims and combinations thereof.

[0012] TECHNICAL SOLUTION

[0013] In an aspect of the present disclosure, a secondary battery diagnostic apparatus includes a storage unit configured to store a positive electrode reference curve and a negative electrode reference curve for charging or discharging of a reference battery, a voltage measurement unit configured to measure a voltage of a target battery during charging or discharging, and a processor configured to generate a plurality of charge and discharge measurement curves based on the voltage measured by the voltage measurement unit at a plurality of different time points, compare each of the generated plurality of charge and discharge measurement curves with an analog curve obtained from the positive electrode reference curve and the negative electrode reference curve stored in the storage unit, and determine a positive electrode adjustment curve and a negative electrode adjustment curve for each of the generated plurality of charge and discharge measurement curves such that an error between each of the charge and discharge measurement curves and the analog curve is within a predetermined level.

[0014] Here, the processor can be configured to compare the positive electrode adjustment curves or the negative electrode adjustment curves determined at a plurality of different time points.

[0015] In addition, the processor can be configured to identify a change in a non-use area of a positive electrode or a negative electrode of the target battery based on a comparison result between the positive electrode adjustment curves or a comparison result between the negative electrode adjustment curves.

[0016] In addition, the processor can be configured to determine the positive electrode adjustment curve and the negative electrode adjustment curve by moving at least one of the positive electrode reference curve and the negative electrode reference curve in a horizontal direction.

[0017] In addition, the processor can be configured to determine the positive electrode adjustment curve and the negative electrode adjustment curve by adjusting a scale of at least one of the positive electrode reference curve and the negative electrode reference curve in a horizontal direction.

[0018] In addition, the voltage measurement unit can be configured to measure a full discharge voltage and a full charge voltage of the target battery, and the processor can be configured to estimate a positive electrode initial value of the positive electrode adjustment curve or a negative electrode initial value of the negative electrode adjustment curve based on the full discharge voltage, and estimate a positive electrode final value of the positive electrode adjustment curve and a negative electrode final value of the negative electrode adjustment curve based on the full charge voltage.

[0019] In addition, the processor can be configured to identify a capacity of the target battery at each time point based on a difference between the positive electrode final value and the positive electrode initial value or a difference between the negative electrode final value and the negative electrode initial value.

[0020] In addition, the processor can be configured to reduce an error between the analog curve and the charge and discharge measurement curve by moving the analog curve in parallel in a vertical direction at each of a plurality of different time points, and identify how much the internal resistance of the target battery increases at the plurality of different time points by comparing magnitudes of the parallel movements of the plurality of different time points.

[0021] In another aspect of the disclosure, a battery pack including the secondary battery diagnosis apparatus according to the disclosure is also provided.

[0022] In another aspect of the disclosure, a vehicle including the secondary battery diagnosis apparatus according to the disclosure is also provided.

[0023] In another aspect of the present disclosure, there is also provided a secondary battery diagnosis method including: storing a positive electrode reference curve and a negative electrode reference curve for charging or discharging of a reference battery; measuring a voltage of a target battery at each of a plurality of different time points while charging or discharging the target battery; generating a charging and discharging measurement curve at each of the plurality of different time points based on the voltage measured in the voltage measuring step; comparing an analog curve obtained from the positive electrode reference curve and the negative electrode reference curve stored in the storing step with each charging and discharging measurement curve generated in the generating step; and determining a positive electrode adjustment curve and a negative electrode adjustment curve for each of the plurality of charging and discharging measurement curves such that an error between the analog curve and the charging and discharging measurement curve is within a predetermined level.

[0024] Advantageous Effects

[0025] According to one embodiment of the present disclosure, the state of a secondary battery can be accurately diagnosed in a simple manner using charging and discharging signals at a plurality of different time points. In addition, according to this embodiment of the present disclosure, the state (particularly, the deterioration state) of a secondary battery can be clearly diagnosed by comparing diagnosis results at a plurality of different time points.

[0026] In addition, in the present disclosure, even if a secondary battery is not disassembled or manufactured in the form of a three-electrode cell, a positive electrode voltage curve and a negative electrode voltage curve can be extracted from charging and discharging voltage curves of a secondary battery at a plurality of different time points.

[0027] In addition, by comparing voltage curves extracted at respective time points with each other, a change in state due to use of a secondary battery can be more effectively recognized.

[0028] Further, in the present disclosure, since a secondary battery is diagnosed in a non-destructive manner, a secondary battery having no abnormality in a diagnosis result can be continuously used, and two or more diagnoses can also be performed.

[0029] In addition, according to an embodiment of the present disclosure, the deterioration degree of a positive electrode and the deterioration degree of a negative electrode of a secondary battery can be diagnosed separately.

[0030] In addition, according to one embodiment of the present disclosure, it is not necessary to store a large amount of reference data or reference values in a storage device such as a storage unit. Therefore, a high-capacity storage unit is not required, and labor, time, and cost for securing a large amount of reference data or reference values can be reduced.

[0031] In addition, according to one embodiment of the present disclosure, in diagnosing the state of the secondary battery, a differential curve such as dV / dQ and dQ / dV can not be used. Thus, the performance or capacity of the processor does not need to be high, and a fast operation can be performed. BRIEF DESCRIPTION OF DRAWINGS

[0032] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the above disclosure, serve to provide further instruction in regard to the technical features of the present disclosure, and therefore the present disclosure is not to be construed as being limited to the accompanying drawings.

[0033] Figure 1 is a block diagram schematically showing a functional configuration of a secondary battery diagnosis apparatus according to an embodiment of the present disclosure.

[0034] Figure 2 is a graph showing an example of a positive electrode reference curve and a negative electrode reference curve stored in a storage unit according to an embodiment of the present disclosure.

[0035] Figure 3 is a graph showing an example of charge and discharge measurement curves generated by a processor at a plurality of different time points according to an embodiment of the present disclosure.

[0036] Figure 4 and Figure 5 is a graph comparatively showing an example of a simulation curve and a charge and discharge measurement curve respectively generated at a first time point and a second time point according to an embodiment of the present disclosure.

[0037] Figure 6 is a graph showing an example of a configuration in which a processor moves a reference curve according to an embodiment of the present disclosure.

[0038] Figure 7 is a graph showing an example of a configuration in which a processor adjusts a scale of a reference curve according to an embodiment of the present disclosure.

[0039] Figure 8 is a graph schematically showing a configuration in which a processor determines a positive electrode initial value and a negative electrode initial value at a certain cycle point according to an embodiment of the present disclosure.

[0040] Figure 9 is a graph schematically showing a configuration in which a processor determines a positive electrode final value and a negative electrode final value according to an embodiment of the present disclosure.

[0041] Figure 10 is a graph schematically showing a configuration in which a processor obtains a positive electrode adjusted curve and a negative electrode adjusted curve by adjusting a positive electrode reference curve and a negative electrode reference curve according to an embodiment of the present disclosure.

[0042] Figure 11 andFigure 12 is a graph that comparatively shows a positive electrode reference curve and a negative electrode reference curve and a positive electrode adjustment curve and a negative electrode adjustment curve at different cycle points by the processor according to an embodiment of the present disclosure.

[0043] Figure 13 is a graph that shows Figure 11 the first positive electrode adjustment curve depicted in Figure 12 the second positive electrode adjustment curve depicted in is a magnified view of a positive electrode non-use area in a state in which the first positive electrode adjustment curve depicted in

[0044] Figure 14 is a graph that schematically shows a configuration in which the processor moves the simulation curve R in parallel in a vertical direction according to an embodiment of the present disclosure.

[0045] Figure 15 is a graph that shows Figure 14 is a magnified graph of part B1 of

[0046] Figure 16 is a flowchart that schematically shows a secondary battery diagnosis method according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0047] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before prior description, it should be understood that the terms used in the specification and the appended claims should not be construed as limited to general and dictionary meanings but interpreted based on the meanings and concepts corresponding to technical aspects of the present disclosure on the basis of the principle that the inventor is able to define the terms appropriately for the best explanation of the present disclosure.

[0048] Therefore, the description proposed herein merely illustrates preferred examples for only the purpose of exemplification and is not intended to limit the scope of the present disclosure, so it should be understood that other equivalents and modifications can be derived from the description without departing from the scope of the present disclosure.

[0049] Figure 1 is a block diagram that schematically shows a functional configuration of a secondary battery diagnosis apparatus according to an embodiment of the present disclosure.

[0050] Referring to Figure 1 , the secondary battery diagnosis apparatus according to the present disclosure can include a storage unit 100, a voltage measurement unit 200, and a processor 300.

[0051] The storage unit 100 can store a positive electrode reference curve and a negative electrode reference curve for charging or discharging of a reference battery. Here, the reference battery can be a secondary battery of the same type as the secondary battery to be diagnosed or a secondary battery designed to have the same characteristics as the secondary battery to be diagnosed. For the reference battery, the positive electrode curve and the negative electrode curve can be extracted while pre-experiencing a charging and / or discharging process. In this case, the charging and discharging process can be performed at the same or similar C-rate as in the charging and discharging process performed when the voltage measurement unit 200 measures the voltage of the target battery later. In addition, the extracted curves can be stored in the storage unit 100 as the positive electrode reference curve and the negative electrode reference curve. Here, in order to obtain the positive electrode reference curve and the negative electrode reference curve, the reference battery can be manufactured in the form of a three-electrode cell or a coin half cell, but the present disclosure is not necessarily limited to this form.

[0052] Figure 2 FIG. 1 is a graph showing examples of the positive electrode reference curve and the negative electrode reference curve stored in the storage unit 100 according to an embodiment of the present disclosure.

[0053] Referring to Figure 2 , the storage unit 100 can store the positive electrode reference curve Rp and the negative electrode reference curve Rn. In this case, the positive electrode reference curve Rp and the negative electrode reference curve Rn can be capacity-voltage graphs displayed on a coordinate system in which the horizontal axis represents capacity (Ah) and the vertical axis represents voltage (V). For example, the positive electrode reference curve Rp can be a curve indicating the positive electrode voltage for each capacity measured while charging a three-electrode cell or a positive electrode half cell as a reference battery. In addition, the negative electrode reference curve Rn can be a curve indicating the negative electrode voltage for each capacity measured while charging a three-electrode cell or a negative electrode half cell as a reference battery.

[0054] In particular, in the present disclosure, as Figure 2 indicated, the storage unit 100 can store each of the positive electrode reference curve Rp and the negative electrode reference curve Rn individually. For example, the storage unit 100 can store one positive electrode reference curve Rp and one negative electrode reference curve Rn obtained while charging the reference battery. That is, the storage unit 100 can not store a plurality of positive electrode reference curves Rp and a plurality of negative electrode reference curves Rn.

[0055] In addition to the above, the storage unit 100 can store data or programs required for other components of the battery diagnosis apparatus according to the present disclosure, such as the voltage measurement unit 200 or the processor 300, to operate or perform their functions.

[0056] The storage unit 100 can be implemented as at least one of a flash type, a hard disk type, an SSD (Solid State Disk) type, an SDD (Solid State Disk Drive) type, a micro multimedia card type, a RAM (Random Access Memory) type, a SRAM (Static RAM) type, a ROM (Read Only Memory) type, an EEPROM (Electrically Erasable Programmable Read Only Memory) type, and a PROM (Programmable Read Only Memory) type, but the present disclosure is not necessarily limited to such a specific form of the storage unit 100.

[0057] The voltage measurement unit 200 can be configured to measure the voltage of the target battery during a charging or discharging process of the target battery. Here, the target battery means a battery to be diagnosed. For example, the target battery can be a secondary battery installed to a battery pack or the like and in use. Also, the secondary battery can be the target battery, and it can be diagnosed to what extent it is deteriorated. Alternatively, the target battery can be a secondary battery before being shipped out from a manufacturing factory, and it can be diagnosed whether there is a defect in the manufacturing process or whether it is manufactured to have a designed characteristic.

[0058] The voltage measurement unit 200 can be configured to measure the voltage while charging or discharging the target battery. In this case, the voltage measurement unit 200 can be configured to measure the charging voltage or the discharging voltage as it is, not the open circuit voltage (OCV) of the target battery. That is, the voltage measurement unit 200 can be configured to measure the closed circuit voltage (CCV) of the target battery. In this case, the resistance characteristic of the target battery can be more accurately estimated. This will be described later.

[0059] The voltage measurement unit 200 desirably measures the voltage of the target battery while charging and discharging at the same or similar C-rate as the C-rate at which the charging and discharging processes are performed for measuring the positive electrode reference curve Rp and the negative electrode reference curve Rn stored in the above storage unit 100. In this case, it is possible to prevent erroneous diagnosis of the target battery due to a C-rate difference.

[0060] The voltage measurement unit 200 can employ various voltage measurement techniques known at the time of filing the present application. For example, the voltage measurement unit 200 can include a voltage sensor known at the time of filing the present application. In particular, when the secondary battery diagnosis apparatus according to the present disclosure is applied to a battery pack, a voltage sensor already provided in the battery pack can be used as the voltage measurement unit 200 according to the present disclosure.

[0061] The processor 300 can generate a charging and discharging measurement curve based on the voltage measured by the voltage measurement unit 200. In particular, when the voltage measurement unit 200 measures the voltage at a plurality of different time points, the processor 300 can generate a plurality of charging and discharging measurement curves based on the voltage measured at the plurality of time points.

[0062] That is, when the voltage measurement unit 200 measures the voltage at a plurality of different time points, the voltage measurement information corresponding to each time point can be transmitted from the voltage measurement unit 200 to the processor 300. In addition, the processor 300 can generate a charge and discharge measurement curve of the target battery at each time point based on the transmitted voltage measurement information corresponding to each time point. Here, the charge and discharge measurement curve can be a charge voltage curve measured during a charge process of the target battery or a discharge voltage curve measured during a discharge process of the target battery.

[0063] Here, the time point can mean a cycle point. That is, the time point can mean the number of charge and discharge cycles. In addition, the plurality of time points can be referred to as two or more time points in which the number of charge and discharge cycles of the secondary battery is different from each other. For example, the plurality of time points can include a first time point and a second time point, in which the second time point can mean a time point after a plurality of charge and discharge cycles are performed from the first time point. As a more specific example, the first time point can mean a BOL (end of life) time point of the target battery, for example, a time point at which the secondary battery is installed in a battery pack and a first charge and discharge cycle is performed. In addition, the second time point can mean a time point at which the 200th charge and discharge cycle is performed on the same target battery. In this embodiment, the processor 300 can generate a charge and discharge measurement curve at the BOL time point and a charge and discharge measurement curve at the 200th cycle point.

[0064] Figure 3 is a graph showing an example of a charge and discharge measurement curve generated by the processor 300 at a plurality of different time points according to an embodiment of the disclosure.

[0065] Referring to Figure 3 , the processor 300 can generate a graph indicating the voltage of the target battery for each capacity at each cycle point based on the voltage value information measured during the charge or discharge process of the target battery at a plurality of different cycle points. That is, the processor 300 can generate a charge and discharge curve indicating a change in voltage according to the capacity of the target battery on a coordinate system in which the capacity (Ah) of the battery is represented on the horizontal axis (x-axis) and the voltage (V) of the battery is represented on the vertical axis (y-axis).

[0066] For example, when the capacity of the target battery increases from the BOL time point (e.g., the first charge) of the target battery to 0, 5 Ah, 10 Ah, 15 Ah,..., the processor 300 can derive a charge and discharge curve as Figure 3the voltage change according to the capacity increase of the target battery as indicated by M2 in FIG. 2B. In this case, M2 is a capacity-voltage curve when the charging is performed at the 200th cycle point, and can be referred to as a second charge and discharge measurement curve.

[0067] In addition, when the target battery is charged at the 200th cycle point, the processor 300 can display the voltage change according to the capacity increase of the target battery as indicated by M2 in FIG. 2B. In this case, M2 is a capacity-voltage curve when the charging is performed at the 200th cycle point, and can be referred to as a second charge and discharge measurement curve. Figure 3

[0068] The voltage change curve for each capacity derived as above at each cycle point can be a charge and discharge measurement curve generated for each time point. Hereinafter, unless otherwise indicated, a plurality of different time points are denoted as a first time point and a second time point, in which the charge and discharge measurement curve of the first time point is denoted as a first charge and discharge measurement curve, and the charge and discharge measurement curve of the second time point is denoted as a second charge and discharge measurement curve.

[0069] In particular, the charge and discharge measurement curves M1, M2 generated by the processor 300 can be curves that indicate the charging voltage or the discharging voltage according to the capacity of the target battery as they are. That is, the charge and discharge measurement curves can not be open circuit voltage (OCV) curves of the target battery at each time point, but can be closed circuit voltage (CCV) curves directly measured at each time point during the charging or discharging process of the target battery.

[0070] In addition, in the embodiments of FIGS. 2A and 2B, Figure 2 and Figure 3 In the embodiments of FIGS. 2A and 2B, the unit of the horizontal axis is denoted as Ah and the unit of the vertical axis is denoted as V, but these units can be expressed in other forms. For example, the capacity unit of the horizontal axis can be expressed as %.

[0071] If a plurality of charge and discharge measurement curves are generated as above, the processor 300 can be configured to compare each generated charge and discharge measurement curve with the simulation curve. For example, the processor 300 can compare the first charge and discharge measurement curve M1 with the simulation curve, and compare the second charge and discharge measurement curve M2 with the simulation curve.

[0072] Here, the simulation curve can be a full cell voltage curve obtained from the positive electrode reference curve and the negative electrode reference curve stored in the storage unit 100. That is, as Figure 2 ​As shown in FIG. 1, when the positive electrode reference curve Rp and the negative electrode reference curve Rn are stored in the storage unit 100, the difference between the positive electrode reference curve Rp and the negative electrode reference curve Rn can be a full-cell type charge and discharge voltage curve. Also, the simulation curve can mean a full-cell type charge and discharge voltage curve of a reference battery. Thus, like the positive electrode reference curve Rp and the negative electrode reference curve Rn, the simulation curve can appear in the form of a voltage curve graph for each capacity.

[0073] The simulation curve can be obtained by the processor 300 directly generating the positive electrode reference curve Rp and the negative electrode reference curve Rn stored in the storage unit 100. Alternatively, the simulation curve can be calculated in advance based on the positive electrode reference curve Rp and the negative electrode reference curve Rn and stored in the storage unit 100. In this case, the processor 300 can access the storage unit 100 to obtain the simulation curve in a read form.

[0074] The simulation curve compared with the first charge and discharge measurement curve and the simulation curve compared with the second charge and discharge measurement curve can be identical to each other. In this case, the storage unit 100 needs to store only one simulation curve to be compared with the charge and discharge measurement curves of a plurality of different cycle points.

[0075] When the simulation curve is obtained in this way, the processor 300 can compare the obtained simulation curve with a plurality of generated charge and discharge measurement curves generated at each point. It will be referred to Figure 4 and Figure 5 This will be described in more detail.

[0076] Figure 4 and Figure 5 are graphs that comparatively show the charge and discharge measurement curves M1, M2 generated at the first time point and the second time point, respectively, and the simulation curve R according to an embodiment of the disclosure.

[0077] First, in Figure 4 , the charge and discharge measurement curve generated by the processor 300 based on the information transmitted by the voltage measurement unit 200 at the first time point is denoted by M1. Also, in Figure 5 , the charge and discharge measurement curve generated by the processor 300 based on the information transmitted by the voltage measurement unit 200 at the second time point is denoted by M2.

[0078] Also, in Figure 4 and Figure 5Among the two, the simulation curve obtained in the same manner from the positive electrode reference curve Rp and the negative electrode reference curve Rn stored in the storage unit 100 is denoted by R. Here, the first charge and discharge measurement curve Ml and the second charge and discharge measurement curve M2 can be voltage curves for each capacity respectively obtained at different cycle points (a first cycle point and a second cycle point) of the secondary battery in use (i.e., the same target battery). In addition, the simulation curve R can be a curve of a reference battery to be compared with the curve of the target battery, which is pre-stored or obtained therefrom.

[0079] Further, in Figure 4 and Figure 5 , the positive electrode reference curve Rp and the negative electrode reference curve Rn are as shown in the embodiment of Figure 2 , and the simulation curve R can be obtained according to a difference between the positive electrode reference curve Rp and the negative electrode reference curve Rn. In addition, Figure 4 and Figure 5 , the charge and discharge measurement curves M1, M2 are considered as shown in Figure 3 .

[0080] As shown in Figure 4 and Figure 5 , there can be a difference between the charge and discharge measurement curves M1, M2 measured and generated at each cycle point of the target battery and the simulation curve R obtained in advance. For example, the simulation curve R can have a form in which the charge or discharge curve of the secondary battery is ideally exhibited as designed. Further, the charge and discharge measurement curves M1, M2 can have a form in which the charge or discharge curve of the manufactured or used secondary battery is actually exhibited at the cycle point. Due to various factors, the charge and discharge measurement curves M1, M2 can have a shape or aspect different from the simulation curve R. The processor 300 can be configured to identify a difference between the simulation curve R and the charge and discharge measurement curves M1, M2.

[0081] In particular, the secondary battery can be deteriorated when used beyond a certain level, which can cause a change in the charge and discharge curve. In addition, even during the manufacturing process of the secondary battery, if a defect occurs due to an error in the process or the like, the charge and discharge curve cannot be exhibited as designed. The processor 300 can confirm whether there is a difference between the charge and discharge measurement curves M1, M2 and the simulation curve R, and in particular, whether the difference is within a certain error range, by comparing the charge and discharge measurement curves M1, M2 with the simulation curve R.

[0082] In addition, the processor 300 can be configured to determine the positive electrode adjustment curve and the negative electrode adjustment curve such that an error between the simulation curve R and the charge and discharge measurement curves Ml, M2 is within a predetermined level. As described above, the simulation curve R can be obtained first based on the positive electrode reference curve Rp and the negative electrode reference curve Rn. Thus, when the positive electrode reference curve Rp and / or the negative electrode reference curve Rp are adjusted, as a result, the simulation curve R can also be adjusted. Thus, as shown in FIGS. 1, 2, and 3, the processor 300 can determine the positive electrode adjustment curve and the negative electrode adjustment curve such that the error between the simulation curve R and the charge and discharge measurement curves Ml, M2 is minimized. Figure 4 and Figure 5 As shown in FIGS. 1, 2, and 3, the processor 300 can adjust the positive electrode reference curve Rp and / or the negative electrode reference curve Rp for each cycle point such that a certain level of error or more between the simulation curve R and the first charge and discharge measurement curve Ml and between the simulation curve R and the second charge and discharge measurement curve M2 is within a certain level. In addition, the finally adjusted positive electrode reference curve Rp and the finally adjusted negative electrode reference curve Rp can become the positive electrode adjustment curve and the negative electrode adjustment curve. In particular, among the plurality of cases in which the positive electrode reference curve Rp and the negative electrode reference curve Rp are adjusted, the processor 300 can determine the adjustment values of the positive electrode reference curve Rp and the negative electrode reference curve Rp in the case in which the error between the simulation curve R and the charge and discharge measurement curves Ml, M2 is minimized as the positive electrode adjustment curve and the negative electrode adjustment curve.

[0083] Here, whether the error between the simulation curve R and the charge and discharge measurement curves Ml, M2 is minimized can be determined using various methods known at the time of filing the present application for comparing the error between two curves. In particular, the simulation curve R and the charge and discharge measurement curves Ml, M2 can have a curved shape. Thus, for example, whether the error between the simulation curve R and the charge and discharge measurement curves Ml, M2 is minimized can be determined by calculating the integral value of the absolute value for the region between the two curves.

[0084] In particular, the processor 300 can determine the positive electrode adjustment curve and the negative electrode adjustment curve for each of the charge and discharge measurement curves Ml, M2 generated for the plurality of time points.

[0085] For example, the processor 300 can compare the first charge and discharge measurement curve Ml generated at the first cycle point with the simulation curve. Also, the processor 300 can determine the positive electrode adjustment curve and the negative electrode adjustment curve such that the error between the first charge and discharge measurement curve Ml and the simulation curve R is within a predetermined level. Also, the processor 300 can compare the second charge and discharge measurement curve M2 generated at the second cycle point with the simulation curve R. Also, the processor 300 can determine the positive electrode adjustment curve and the negative electrode adjustment curve such that the error between the second charge and discharge measurement curve M2 and the simulation curve R is within a predetermined level. Here, the positive electrode adjustment curve and the negative electrode adjustment curve determined at the first cycle point can be different from the positive electrode adjustment curve and the negative electrode adjustment curve determined at the second cycle point. Hereinafter, the positive electrode adjustment curve and the negative electrode adjustment curve determined for the first cycle point are referred to as a first positive electrode adjustment curve and a first negative electrode adjustment curve, and the positive electrode adjustment curve and the negative electrode adjustment curve determined for the second cycle point are denoted as a second positive electrode adjustment curve and a second negative electrode adjustment curve.

[0086] According to this configuration of the disclosure, various state information about the target battery can be obtained based on the finally determined positive electrode adjustment curve and the finally determined adjustment curve.

[0087] Also, it can be considered that the simulation curve by the finally determined positive electrode adjustment curve and the finally determined negative electrode adjustment curve has almost the same form as the charge and discharge measurement curve M1 or M2. Hereinafter, for convenience of explanation, the full cell voltage curve obtained by the positive electrode adjustment curve and the negative electrode adjustment curve will be referred to as a simulation adjustment curve, to be distinguished from the simulation curve R which is the full cell voltage curve obtained by the initial positive electrode reference curve Rp and the negative electrode reference curve Rp.

[0088] Since the simulation adjustment curve can be the same as or similar to the charge and discharge measurement curve M, the positive electrode adjustment curve and the negative electrode adjustment curve forming the simulation adjustment curve can be predicted as the positive electrode curve and the negative curve for the charge and discharge measurement curve M1, M2. That is, it can be considered that the positive electrode adjustment curve and the negative electrode adjustment curve at each cycle point are the same as or almost similar to the positive electrode curve and the negative curve at the corresponding cycle point.

[0089] Therefore, according to the disclosure, even if the target battery is not disassembled or manufactured in the form of a three-electrode battery, the positive electrode curve and the negative curve information of the target battery can be identified. Also, through the curve information identified in this way, the state of the target battery can be more easily predicted.

[0090] In particular, according to the embodiments of the present disclosure, it can be more easily predicted whether deterioration occurs in a secondary battery in use, and if deterioration occurs, it can be more easily predicted the degree or type of deterioration, through the positive electrode adjustment curve and the negative electrode adjustment curve.

[0091] Further, according to the embodiments of the present disclosure, the positive electrode curve and the negative electrode curve can be obtained in a simple manner at each cycle point. In particular, even if only one positive electrode reference curve Rp and one negative electrode reference curve Rn are stored in the storage unit 100, the present disclosure can be implemented. That is, it is not necessary to store a plurality of positive electrode reference curves Rp and / or a plurality of negative electrode reference curves Rn in the storage unit 100. Accordingly, the capacity of the storage unit 100 does not need to be high, and it is not necessary to perform many pre-tests to store the reference curves.

[0092] In addition, according to the embodiments of the present disclosure, a closed circuit voltage (CCV) curve is used instead of an open circuit voltage (OCV) curve. Accordingly, the change in resistance can be measured during a continuous charging or discharging process. In particular, the open circuit voltage curve can be obtained in the form of an intermediate value between a charging voltage curve and a discharging voltage curve, or can be obtained by stopping charging or discharging during a charging or discharging process and measuring the voltage after a certain time in a state in which both ends of the battery are open. Accordingly, in the case of such an open circuit voltage curve, the method of obtaining the open circuit voltage curve is complex, and it can be difficult to accurately measure the change in resistance during a continuous charging or discharging process. However, according to the embodiments of the present disclosure, by using a charging voltage curve or a discharging voltage curve measured in a state in which a charging and discharging current flows instead of an open circuit voltage curve, the change in resistance can be accurately measured during a continuous charging or discharging process.

[0093] The processor 300 can optionally include a central processing unit (CPU), an application specific integrated circuit (ASIC), a chipset, a logic circuit, a register, a communication modem, a data processing device, etc. known in the art to perform various control logics performed in the present disclosure, or can be expressed using these terms. In addition, when the control logics are implemented in software, the processor 300 can be implemented as a set of program modules. In this case, the program modules can be stored in an internal memory or an external storage unit 100, etc. and executed by the processor 300. The storage unit 100 can be provided inside or outside the processor 300 and can be connected to the processor 300 through various well-known devices.

[0094] In particular, if the diagnostic device according to the present disclosure is implemented in the form of being included in a battery pack, the battery pack can include a control device called a micro controller unit (MCU) or a battery management system (BMS). At this time, the processor 300 can be implemented by a component such as the MCU or the BMS provided in a general battery pack.

[0095] Further, in the present specification, terms such as "for" or "configured to" used for operations or functions of the processor 300 can include the meaning of "programmed to".

[0096] The processor 300 can be configured to compare the positive electrode adjustment curve or the negative electrode adjustment curve determined for a plurality of different time points.

[0097] For example, the processor 300 can be configured to compare a first positive electrode adjustment curve determined at a first cycle point and a second positive electrode adjustment curve determined at a second cycle point. Alternatively, the processor 300 can be configured to compare a first negative electrode adjustment curve determined at a first cycle point and a second negative electrode adjustment curve determined at a second cycle point.

[0098] That is, the first positive electrode adjustment curve can be regarded as a positive electrode curve of the target battery at the first cycle point. In addition, the second positive electrode adjustment curve can be regarded as a positive electrode curve of the target battery at the second cycle point. Thus, by comparing the first positive electrode adjustment curve and the second positive electrode adjustment curve with each other, it can be easily understood how the positive electrode curve changes according to the deterioration of the target battery. In addition, by the change of the positive electrode curve, it can be more easily predicted the change of the state of the target battery.

[0099] In addition, the first negative electrode adjustment curve can be regarded as a negative electrode curve of the target battery at the first cycle point, and the second negative electrode adjustment curve can be regarded as a negative electrode curve of the target battery at the second cycle point. Thus, by comparing the first negative electrode adjustment curve and the second negative electrode adjustment curve with each other, it can be easily understood how the negative electrode curve changes according to the deterioration of the target battery.

[0100] A more specific embodiment of the comparison between the positive electrode adjustment curve and the like will be described later.

[0101] The processor 300 can be configured to determine the positive electrode adjustment curve and the negative electrode adjustment curve by moving the positive electrode reference curve Rp and / or the negative electrode reference curve Rn on the coordinate axis. It will be described in more detail with reference to Figure 6 A more detailed description thereof will be given.

[0102] Figure 6 is a graph showing an example of a configuration in which the processor 300 moves the reference curve according to an embodiment of the disclosure. For the present embodiment and other embodiments below, features different from those of the previous embodiments will be described in detail, and features identical or similar to those of the previous embodiments will not be described in detail.

[0103] Referring to Figure 6 , similarly to Figure 2The positive electrode reference curve and the negative electrode reference curve stored in the storage unit 100 are denoted by Rp and Rn, respectively. Here, the positive electrode reference curve Rp and the negative electrode reference curve Rn can be expressed in the form of a voltage for each capacity.

[0104] The processor 300 can move at least one of the positive electrode reference curve Rp and the negative electrode reference curve Rn in the horizontal direction. For example, the processor 300 can move the positive electrode reference curve indicated by Rp in the -x axis direction as indicated by an arrow A1. In this case, the positive electrode reference curve can be displayed on the coordinate plane in a position and a shape indicated by Rp'. In addition, the processor 300 can move the negative electrode reference curve indicated by Rn in the -x axis direction as indicated by an arrow A2. In this case, the negative electrode reference curve can be displayed on the coordinate plane in a position and a shape indicated by Rn'.

[0105] If the processor 300 moves at least one of the positive electrode reference curve Rp and the negative electrode reference curve Rn as above, the position and / or the shape of the simulation curve indicated by R can change. Accordingly, the processor 300 can move the positive electrode reference curve Rp and the negative electrode reference curve Rn so that the position and / or the shape of the adjusted simulation curve (i.e., the simulation adjusted curve) match the position and / or the shape of the charge and discharge measurement curves M1, M2 as much as possible. In Figure 6 In the embodiment, the shape of the positive electrode reference curve before the movement is indicated by Rp, and the shape thereof after the movement is indicated by Rp'. In addition, the shape of the negative electrode reference curve before the movement is indicated by Rn, and the shape thereof after the movement is indicated by Rn'. In addition, if the simulation curve R is adjusted by moving the positive electrode reference curve and the negative electrode reference curve to match the charge and discharge measurement curves M or to have an error within a certain level, the positive electrode curve indicated by Rp' and the negative electrode curve indicated by Rn' can be determined as the positive electrode adjusted curve and the negative electrode adjusted curve, respectively.

[0106] In addition, it can be considered that the positive electrode adjusted curve Rp' and the negative electrode adjusted curve Rn' determined in this way represent the positive electrode curve and the negative electrode curve of the charge and discharge measurement curve M1 or M2 for the target battery. For example, due to the adjustment described in the embodiment of Figure 6 Due to the adjustment, when the simulation adjusted curve matches the first charge and discharge measurement curve M1, the determined positive electrode adjusted curve Rp' and the determined negative electrode adjusted curve Rn' can be regarded as the positive electrode curve and the negative electrode curve of the target battery at the first time point. In addition, due to the adjustment, when the simulation adjusted curve matches the second charge and discharge measurement curve M2, the determined positive electrode adjusted curve Rp' and the determined negative electrode adjusted curve Rn' can be regarded as the positive electrode curve and the negative electrode curve of the target battery at the second time point.

[0107] In addition, in the embodiment, the processor 300 can determine the positive electrode adjusted curve Rp' and the negative electrode adjusted curve Rn' by moving the positive electrode reference curve Rp and the negative electrode reference curve Rn in the horizontal direction.Figure 6 In this regard, the positive electrode reference curve Rp and the negative electrode reference curve Rn are described as moving in the horizontal direction (x-axis direction), but the positive electrode reference curve Rp and the negative electrode reference curve Rn can move in the vertical direction (y-axis direction) or in the diagonal direction to obtain the positive electrode adjusted curve Rp' and the negative electrode adjusted curve Rn'.

[0108] In addition, the processor 300 can be configured to determine the positive electrode adjusted curve Rp' and the negative electrode adjusted curve Rn' by adjusting the scale of the positive electrode reference curve Rp and / or the negative electrode reference curve Rn on the coordinate system. Reference will be made to Figure 7 This will be described in more detail.

[0109] Figure 7 is a graph showing an example of a configuration in which the processor 300 adjusts the scale of the reference curve according to an embodiment of the disclosure.

[0110] Referring to Figure 7 , the processor 300 can be configured to adjust the scale of the positive electrode reference curve Rp stored in the storage unit 100 in the horizontal direction (i.e., in the x-axis direction). In particular, the processor 300 can adjust the scale of the positive electrode reference curve Rp to be reduced, as indicated by an arrow A3. Alternatively, the processor 300 can adjust the scale of the positive electrode reference curve Rp to be expanded in the direction opposite to the arrow A3. Such scale adjustment can be referred to as horizontal scale adjustment. In particular, when the secondary battery is deteriorated or defective, the positive electrode curve Rp and / or the negative electrode curve Rn are often narrowed in the horizontal direction, and thus the processor 300 adjusts the scale of the positive electrode reference curve Rp and / or the negative electrode reference curve Rn to be reduced.

[0111] More specifically, with respect to the positive electrode reference curve indicated by Rp, the processor 300 can move the point having the maximum capacity and in the fully charged state along the A3 direction, which is the horizontal direction, in a state in which the point having 0 (zero) capacity in the fully discharged state is fixed. That is, the processor 300 can move the point P1 corresponding to the end-of-charge voltage (4.3 V in the graph) in the -x-axis direction while the point corresponding to the start-of-charge voltage (3.5 V in the graph) is fixed. In addition, by moving the far end as above, the positive electrode reference curve can be reduced.

[0112] For example, if the positive electrode reference curve Rp is reduced by 6%, the capacity of the full charge voltage can be moved from the point P1 to the point P2. In this case, the positive electrode adjusted curve Rps1 can be formed. In addition, if the positive electrode reference curve Rp is reduced by 8%, the point P1 can be moved to the point P3. In this case, the positive electrode adjusted curve can be formed like Rps2. That is, in this curve, Rps2 can be reduced more than Rps1 based on Rp.

[0113] If the error between the analog curve R adjusted in the state in which the positive electrode reference curve Rp is scaled down like Rps1 and the charge and discharge measurement curve Ml or M2 is within a certain level, the processor 300 can determine that the Rps1 curve is the positive electrode adjustment curve at the corresponding time point. For example, if the analog curve is formed in the state in which the positive electrode reference curve is scaled down to Rps1 similarly to the first charge and discharge measurement curve Ml, the processor 300 can determine that the Rps1 curve is the positive electrode adjustment curve Rp' at the first cycle point.

[0114] In addition, if the error between the analog curve R adjusted in the state in which the positive electrode reference curve Rp is scaled down like Rps2 and the charge and discharge measurement curve Ml or M2 is within a certain level, the processor 300 can determine that the Rps2 curve is the positive electrode adjustment curve at the corresponding time point. For example, if the analog curve is formed in the state in which the positive electrode reference curve is scaled down to Rps2 similarly to the second charge and discharge measurement curve M2, the processor 300 can determine that the Rps2 curve is the positive electrode adjustment curve Rp' at the second cycle point.

[0115] Further, in the embodiment of Figure 7 , a configuration for adjusting the scale of the positive electrode reference curve Rp is described, but the scale of the negative electrode reference curve Rn can also be adjusted in a similar manner. Here, the scale adjustment ratio of the negative electrode reference curve Rn can be the same as or different from the scale adjustment ratio of the positive electrode reference curve Rp.

[0116] Further, in the present disclosure, at the first cycle point and the second cycle point, the scale of the positive electrode reference curve Rp and / or the scale of the negative electrode reference curve Rn can be adjusted to different degrees. For example, the scale adjustment of the positive electrode reference curve Rp at the second cycle point can be scaled down more than the scale adjustment of the positive electrode reference curve Rp at the first cycle point.

[0117] In particular, in the secondary battery diagnosis apparatus according to the present disclosure, the processor 300 can determine the positive electrode adjustment curve Rp' and the negative electrode adjustment curve Rn' by moving the positive electrode reference curve Rp and / or the negative electrode reference curve Rn in the horizontal direction as shown in Figure 6 Figure 7 In particular, in the secondary battery diagnosis apparatus according to the present disclosure, the processor 300 can determine the positive electrode adjustment curve Rp' and the negative electrode adjustment curve Rn' by moving the positive electrode reference curve Rp and / or the negative electrode reference curve Rn in the horizontal direction as shown in

[0118] That is, when determining the positive electrode adjustment curve Rp' and the negative electrode adjustment curve Rn' at each cycle point, the processor 300 can move the positive electrode reference curve Rp and / or the negative electrode reference curve Rn in the horizontal direction and simultaneously adjust the scale thereof in the horizontal direction.

[0119] ​According to this embodiment of the present disclosure, the positive electrode curve and the negative electrode curve of the charge and discharge measurement curves M1, M2 for the target battery at the plurality of cycle points can be obtained in a simple manner. In particular, according to the embodiment of the present disclosure, a large amount of data of the positive electrode reference curve Rp and the negative electrode reference curve Rn does not need to be stored. Thus, according to this embodiment of the present disclosure, the storage unit 100 and the processor 300 having a high capacity or high performance can not be provided.

[0120] If the scale of the positive electrode reference curve Rp and / or the negative electrode reference curve Rn is adjusted (in particular, reduced) in the horizontal direction so as to minimize the error between the charge and discharge measurement curves M1, M2 at each of the plurality of cycle points and the simulation curve R as in the present embodiment, the processor 300 can estimate the positive electrode deterioration rate and / or the negative electrode deterioration rate by the reduction value.

[0121] For example, if the positive electrode adjustment curve Rp' is obtained by reducing the positive electrode reference curve Rp by 3% in a state where the capacity value of the positive electrode reference curve Rp at the end-of-charge voltage is 100 [Ah] so as to minimize the error between the second charge and discharge measurement curve M2 and the simulation curve R, the capacity value of the positive electrode adjustment curve Rp' at the end-of-charge voltage can become 97 [Ah]. In this case, the reduction value of the positive electrode reference curve Rp can be regarded as 3%. Accordingly, the processor 300 can judge that the positive electrode deterioration rate of the target battery at the second cycle point is 3%.

[0122] In addition, if the negative electrode adjustment curve Rn' is obtained by reducing the negative electrode reference curve Rn by 0.1% in a state where the capacity value of the negative electrode reference curve Rn at the end-of-charge voltage is 100 [Ah] so as to minimize the error between the second charge and discharge measurement curve M2 and the simulation curve R, the capacity value of the negative electrode adjustment curve Rn' at the end-of-charge voltage can become 99.9 [Ah]. In this case, the reduction value of the negative electrode reference curve Rn can be regarded as 0.1%. Accordingly, the processor 300 can judge that the negative electrode deterioration rate of the target battery at the second cycle point is 0.1%.

[0123] In addition, the unit of the capacity axis in the coordinate system showing the charge and discharge measurement curves M1, M2 and the simulation curve R can be expressed as [%] rather than [Ah]. In this case, the reduction value can be more easily obtained.

[0124] According to this embodiment of the present disclosure, by the degree of scaling, particularly the degree of reduction, of the positive electrode reference curve Rp and the negative electrode reference curve Rn, the positive electrode deterioration rate and / or the negative electrode deterioration rate at each cycle point can be more clearly and simply obtained. In particular, the secondary battery can not properly exhibit its capacity due to the formation of a conduction path, gas generation, active material deterioration, and the like at a certain point during use. According to this embodiment, by adjusting the curves to be scaled, the positive electrode curve and the negative electrode curve that substantially reflect such deterioration can be obtained at each use time point.

[0125] In particular, in the embodiments of the present disclosure, the positive electrode adjustment curve Rp' and / or the negative electrode adjustment curve Rn' can be determined for each of the plurality of cycle points. Accordingly, for a plurality of different cycle points, the positive electrode deterioration rate and / or the negative electrode deterioration rate of one target battery can be obtained respectively. Thus, in this case, by comparing the positive electrode deterioration rate and / or the negative electrode deterioration rate at different cycle points with each other, the positive electrode deterioration rate change and / or the negative electrode deterioration rate change can be identified according to the use of the target battery.

[0126] For example, if the positive electrode deterioration rate at the first cycle point is 1% and the positive electrode deterioration rate at the second cycle point is 5%, it can be judged that the positive electrode deterioration rate of the target battery increased by 4% during use from the first cycle point to the second cycle point.

[0127] As another example, if the negative electrode deterioration rate at the first cycle point is 0.05% and the negative electrode deterioration rate at the second cycle point is 0.15%, it can be judged that the negative electrode deterioration rate of the target battery increased by 0.1% during use from the first cycle point to the second cycle point.

[0128] The voltage measurement unit 200 can be configured to measure the fully discharged voltage and the fully charged voltage of the target battery. Here, the fully discharged voltage can mean the voltage when the target battery is in a fully discharged state, that is, when the SOC (State of Charge) of the target battery is 0. In particular, the fully discharged voltage can be the open circuit voltage (OCV) when the SOC is 0 (zero). In addition, the fully charged voltage can mean the voltage when the target battery is in a fully charged state, that is, when the SOC of the target battery is 100%. In particular, the fully charged voltage can be the open circuit voltage when the SOC is 100%.

[0129] The processor 300 can estimate the positive electrode initial value of the positive electrode adjustment curve or the negative electrode initial value of the negative electrode adjustment curve at each cycle point based on the full discharge voltage at each cycle point. Here, when the positive electrode adjustment curve is determined by adjusting the positive electrode reference curve, the positive electrode initial value can be a point at which the capacity is 0 (zero) on the positive electrode adjustment curve. Also, when the negative electrode adjustment curve is determined by adjusting the negative electrode reference curve, the negative electrode initial value can be a point at which the capacity is 0 (zero) on the negative electrode adjustment curve. That is, when the target battery starts to be charged (fully discharged) at each cycle point, the positive electrode initial value and the negative electrode initial value can be regarded as the starting point of the positive electrode curve and the starting point of the negative electrode curve.

[0130] The processor 300 can arbitrarily set at least one of the positive electrode initial value and the negative electrode initial value, and obtain the other from the full discharge voltage. This will be described in more detail with reference to Figure 8 This will be described in more detail.

[0131] Figure 8 FIG. 1 is a diagram schematically illustrating a configuration in which the processor 300 determines the positive electrode initial value and the negative electrode initial value at a specific cycle point according to an embodiment of the disclosure.

[0132] The positive electrode reference curve Rp and the negative electrode reference curve Rn can be stored in the storage unit 100 in the form shown in Figure 8 Alternatively, the positive electrode reference curve Rp and the negative electrode reference curve Rn of the target battery can be adjusted reference curves after the positive electrode reference curve Rp and the negative electrode reference curve Rn stored in the storage unit 100 are moved as shown in Figure 8 Figure 6 Alternatively, the positive electrode reference curve Rp and the negative electrode reference curve Rn of the target battery can be adjusted reference curves after the positive electrode reference curve Rp and the negative electrode reference curve Rn stored in the storage unit 100 are moved as shown in Figure 7

[0133] Also, the processor 300 can set an arbitrary point (e.g., pi) on the positive electrode reference curve Rp as the positive electrode initial value. In this case, the positive electrode initial value can be pre-stored in the storage unit 100 or configured to be calculated by the processor 300 through a predetermined calculation method. For example, the positive electrode initial value can be configured to have a predetermined value distinguished for each number of charge and discharge cycles with respect to the battery in use. For example, the positive electrode initial value can be configured to have a different value each time 100 cycles elapse.

[0134] If the positive electrode initial value pi is set as above, the processor 300 can determine the negative electrode initial value based on the full discharge voltage measured by the voltage measurement unit 200. For example, at the first cycle point, if the full discharge voltage (i.e., the voltage when the SOC of the target battery is 0) is measured to be V1, the processor 300 searches for a point on the negative electrode reference curve Rn that differs from the positive electrode initial value pi by V1. In Figure 8 ​​In this regard, a point that differs from the positive electrode initial value pi by V1 is indicated by ni. In addition, the processor 300 can determine the search point ni as the negative electrode initial value.

[0135] In addition, the processor 300 can be configured to estimate a positive electrode final value of the positive electrode adjustment curve and a negative electrode final value of the negative electrode adjustment curve at each cycle point based on the full charge voltage at each cycle point. Here, when the positive electrode adjustment curve is determined by adjusting the positive electrode reference curve, the positive electrode final value can be a point at which the capacity is 100% on the positive electrode adjustment curve. In addition, when the negative electrode adjustment curve is determined by adjusting the negative electrode reference curve, the negative electrode final value can be a point at which the capacity is 100% on the negative electrode adjustment curve. That is, when the target battery stops charging (full charging), the positive electrode final value and the negative electrode final value can be regarded as a final value of the positive electrode curve and a final value of the negative electrode curve. This will be described in more detail with reference to FIGS. 6 and 7. Figure 9 This will be described in more detail.

[0136] Figure 9 FIG. 5 is a diagram schematically illustrating a configuration in which the processor 300 determines the positive electrode final value and the negative electrode final value according to an embodiment of the disclosure.

[0137] Referring to FIG. 5, Figure 9 , the positive electrode reference curve Rp and the negative electrode reference curve Rn are illustrated. As described above with reference to FIG. 4, Figure 8 The positive electrode reference curve Rp and the negative electrode reference curve Rn can be curves that are pre-stored in the storage unit 100 or curves that are moved and / or adjusted in scale therefrom. In addition, on each reference curve, a positive electrode initial value pi and a negative electrode initial value ni are indicated, respectively. The positive electrode initial value pi and the negative electrode initial value ni can be obtained as described above with reference to FIG. 4. When the positive electrode initial value pi and the negative electrode initial value ni are determined in this way, the processor 300 can obtain a straight line L1 connecting the positive electrode initial value pi and the negative electrode initial value ni. Figure 8

[0138] In addition, the processor 300 can obtain another straight line L2 that is parallel to the straight line L1 and has both ends that are moved on the positive electrode reference curve Rp and the negative electrode reference curve Rn. The processor 300 can move the straight line L2 in the left and right directions as indicated by A4 in the drawing. Here, at the first cycle point, if the full charge voltage of the target battery transmitted from the voltage measurement unit 200 is V2, the processor 300 can search for a point at which the voltage difference between both ends is V2 while moving the straight line L2 as indicated by the arrow A4.

[0139] ​In this configuration, when line L2 moves, processor 300 can maintain line L2 as parallel to line L1. Furthermore, processor 300 allows both ends of line L2 to move only along the positive reference curve Rp and the negative reference curve Rn. That is, processor 300 allows one end of line L2 to move only along the positive reference curve Rp, such as... Figure 9 As indicated by arrow A5. Additionally, processor 300 can allow the other end of straight line L2 to move only along the negative reference curve Rn, as... Figure 9 As indicated by arrow A6. In addition, when determining the final position of the straight line L2, which is parallel to L1 and has a voltage difference of V2 between its two ends, the processor 300 can determine the end of the straight line L2 at the final position on the positive reference curve Rp as the positive final value pf, and its end on the negative reference curve Rn as the negative final value nf.

[0140] Furthermore, if the positive electrode initial value pi, negative electrode initial value ni, positive electrode final value pf, and negative electrode final value nf are determined as described above, then the determined positive electrode initial value pi, the determined negative electrode initial value ni, the determined positive electrode final value pf, and the determined negative electrode final value nf can be used to determine the positive electrode adjustment curve and the negative electrode adjustment curve. (Refer to...) Figure 10 This will be described in more detail.

[0141] Figure 10 This is a diagram illustrating the configuration of obtaining the positive electrode adjustment curve Rp' and the negative electrode adjustment curve Rn' by adjusting the positive electrode reference curve Rp and the negative electrode reference curve Rn by the processor 300 according to an embodiment of the present disclosure.

[0142] Reference Figure 10 If as above Figure 8 and Figure 9 The implementation describes the determination of the positive electrode initial value pi, the negative electrode initial value ni, the positive electrode final value pf, and the negative electrode final value nf, and the positive electrode adjustment curve Rp' and the negative electrode adjustment curve Rn' can be obtained based on these values.

[0143] More specifically, the positive electrode adjustment curve Rp' and the negative electrode adjustment curve Rn' can be represented on the coordinate plane indicating the voltage for each capacity, like the positive electrode reference curve Rp and the negative electrode reference curve Rn. In addition, the processor 300 can obtain the positive electrode adjustment curve Rp' by moving the positive electrode reference curve Rp in the horizontal direction (in particular, in the -x-axis direction) so that the positive electrode initial value pi is located on the y-axis. In addition, the processor 300 can obtain the negative electrode adjustment curve Rn' by adjusting the negative electrode reference curve Rn in a similar manner. In other words, the processor 300 can obtain the negative electrode adjustment curve Rn' by moving the negative electrode reference curve Rn in the horizontal direction (in particular, in the -x-axis direction) so that the negative electrode initial value ni is located on the y-axis, i.e., so that the x-coordinate value of the negative electrode initial value ni has a capacity of 0 (zero).

[0144] If the positive electrode reference curve Rp and the negative electrode reference curve Rn are changed in this manner, the full-cell voltage curve obtained from the difference between the positive electrode reference curve Rp and the negative electrode reference curve Rn can also change. For example, when the full-cell voltage curve R appears as indicated in Figure 9 , if the positive electrode reference curve and the negative electrode reference curve are adjusted to change the position and / or shape, the full-cell voltage curve can also be obtained in a position and / or shape different from the position and / or shape of the existing R, as indicated by R' in Figure 10 . In addition, when the full-cell voltage curve obtained in this manner matches or is within a certain error range with the charge and discharge measurement curves M1, M2 of the target battery, the processor 300 can determine the adjusted positive electrode reference curve Rp' as the positive electrode adjustment curve at the corresponding time point and determine the adjusted negative electrode reference curve Rn' as the negative electrode adjustment curve at the corresponding time point.

[0145] If the full-cell voltage curve R' does not match or is outside the error range with the charge and discharge measurement curves M1, M2 even in the state in which the positive electrode reference curve and the negative electrode reference curve are changed in this manner, the processor 300 can repeat the process described above with reference to Figure 8 to Figure 10 , in the state in which the positive electrode initial value pi becomes another value. Alternatively, with respect to the adjusted positive curve Rp' and the adjusted negative curve Rn' obtained in Figure 10 , the processor 300 can perform additional adjustments such as the movement in the horizontal direction and / or the reduction described above with reference to Figure 6 and Figure 7 .

[0146] In addition, by confirming the shape of the full cell voltage profile (which is obtained by repeated adjustment and is most consistent with the charge and discharge measurement profiles M1, M2), the final positive electrode adjustment profile and the final negative electrode adjustment profile at the corresponding time point can be determined.

[0147] In addition, the processor 300 can adjust at least one of the proportion in the region between the positive electrode initial value pi and the positive electrode final value pf for the positive electrode adjustment profile and the proportion in the region between the negative electrode initial value ni and the negative electrode final value nf for the negative electrode adjustment profile. In addition, the processor 300 can be configured such that the error between the simulation profile R and the charge and discharge measurement profiles M is within a certain level, accordingly.

[0148] For example, the processor 300 can adjust the proportion of the positive electrode adjustment profile Rp' shown in Figure 7 in the horizontal direction in the form of being reduced in the horizontal direction as described in Figure 10 More specifically, the processor 300 can reduce or expand the adjusted positive electrode reference profile Rp' as shown in Figure 10 in the horizontal direction. That is, the processor 300 can reduce or expand the adjusted negative electrode adjustment profile Rn' as shown in Figure 10 in the horizontal direction by moving the negative electrode final value nf in the ±x-axis direction in a state in which the negative electrode initial value ni is fixed on the voltage coordinate axis.

[0149] In addition, by the proportion adjustment, the simulation adjustment profile R' can be made more consistent with the charge and discharge measurement profiles M1, M2. In particular, when a sufficiently satisfactory simulation adjustment profile is not obtained even if the positive electrode reference profile and / or the negative electrode reference profile are moved in the horizontal direction as described above, or when it is intended to want to obtain a simulation adjustment profile R' more consistent with each charge and discharge measurement profile M1, M2, the proportion adjustment can be performed.

[0150] In addition, the proportion adjustment can be performed without being limited to the region between the positive electrode initial value pi, the positive electrode final value pf, the negative electrode initial value ni, and the negative electrode final value nf. In particular, the processor 300 can first perform the proportion adjustment before determining the positive electrode initial value pi, the positive electrode final value pf, the negative electrode initial value ni, and the negative electrode final value nf. For example, the processor 300 can perform the proportion adjustment in Figure 8the positive electrode reference curve and / or the negative electrode adjustment curve before determining the positive electrode initial value pi and the negative electrode initial value ni in the graph of the previous embodiment. In addition, the processor 300 can determine the positive electrode initial value pi, the positive electrode final value pf, the negative electrode initial value ni, and the negative electrode final value nf with respect to the proportion-adjusted curves

[0151] In particular, in the present disclosure, as the charge and discharge measurement curves, there can be at least two curves M1, M2 measured at different cycle points. Accordingly, for each charge and discharge measurement curve, the above-described processes can be performed separately to determine the positive electrode adjustment curve and the negative electrode adjustment curve corresponding to the charge and discharge measurement curve. Figure 6 to Figure 10 The configuration for determining the positive electrode adjustment curve and the negative electrode adjustment curve is described. That is, in the previous embodiment, the processor 300 can determine the positive electrode adjustment curve and the negative electrode adjustment curve corresponding to the first charge and discharge measurement curve M1 by the above-described process with respect to the first charge and discharge measurement curve M1. In addition, with respect to the second charge and discharge measurement curve M2, the processor 300 can determine the positive electrode adjustment curve and the negative electrode adjustment curve corresponding to the second charge and discharge measurement curve M2 by the above-described process.

[0152] According to this embodiment of the present disclosure, if only the charge and discharge measurement curves M1, M2 of the target battery are obtained at each of the plurality of time points, the positive electrode curve and the negative electrode curve of the charge and discharge of the target battery for each time point can be obtained by a relatively simple process of moving one positive electrode reference curve and one negative electrode reference curve and / or adjusting the proportion thereof. In addition, various information about the state of the target battery can be obtained through the positive electrode curve and the negative electrode curve at each time point.

[0153] In particular, in the present embodiment, in the process of obtaining the positive electrode curve and the negative electrode curve, a capacity differential curve such as dV / dQ or dQ / dV (Q is capacity, and V is voltage) and a complex type of calculation are not necessary.

[0154] In addition, in the present disclosure, it can be easier to identify how the characteristics or the state of the secondary battery change according to the deterioration of the secondary battery. In particular, according to the embodiments of the present disclosure, the signal extracted at the BOL state and the signal extracted at the deteriorated state can be compared with each other. Accordingly, with respect to the target battery, it can be easier to obtain information about how the deterioration rate or the deterioration aspect compared to the initial state.

[0155] In addition, the processor 300 can be configured to identify the capacity of the target battery at each time point based on the difference between the positive electrode final value pf and the positive electrode initial value pi.

[0156] For example, based on the positive electrode final value pf and the positive electrode initial value pi determined at the first cycle point, the processor 300 can determine a difference between them. Also, the processor 300 can identify the capacity of the target battery at the first cycle point based on the difference between the positive electrode final value pf and the positive electrode initial value pi. Also, based on the positive electrode final value pf and the positive electrode initial value pi determined at the second cycle point, the processor 300 can identify a difference between them. Also, the processor 300 can identify the capacity of the target battery at the second cycle point based on the difference between the positive electrode final value pf and the positive electrode initial value pi.

[0157] Here, the difference between the positive electrode final value and the positive electrode initial value (pf-pi) can be the same as the difference between the negative electrode final value and the negative electrode initial value (nf-ni). Thus, it can be considered that the processor 300 identifies the capacity of the target battery based on the difference between the negative electrode final value and the negative electrode initial value (nf-ni).

[0158] In particular, the processor 300 can obtain the difference between the positive electrode final value and the positive electrode initial value (pf-pi) or the difference between the negative electrode final value and the negative electrode initial value (nf-ni) as a percentage. For example, the difference between the final-estimated positive electrode final value and the positive electrode initial value (pf-pi) can be expressed as a percentage corresponding to a standard capacity. Here, the standard capacity is a value compared with the difference between the final-estimated positive electrode final value and the positive electrode initial value (pf-pi), and can be a value pre-stored in the storage unit 100 or the like.

[0159] As a more specific example, when the standard capacity is 60 Ah and the difference between the final-estimated positive electrode final value and the positive electrode initial value (pf-pi) at a certain cycle point is 55 Ah, in order to express this as a percentage, the following calculation can be performed: (55 / 60) x 100 = 92. At this time, the difference between the positive electrode final value and the positive electrode initial value (pf-pi) at the corresponding time point can be considered as 92%.

[0160] As another example, in the voltage graph for each capacity used or generated by the processor 300, when the unit of the capacity axis is %, the processor 300 can calculate the difference between the positive electrode final value and the positive electrode initial value (pf-pi) with the finally obtained positive electrode adjustment curve. For example, in the voltage graph of FIG. 6B, when the capacity axis is expressed in % units, the x-coordinate value of the positive electrode final value pf can be considered as a value expressing the difference between the positive electrode final value and the positive electrode initial value (pf-pi) as a percentage. Figure 10 In the voltage graph of FIG. 6B, when the capacity axis is expressed in % units, the x-coordinate value of the positive electrode final value pf can be considered as a value expressing the difference between the positive electrode final value and the positive electrode initial value (pf-pi) as a percentage. That is, when the x-coordinate value of the positive electrode final value pf in the voltage graph of FIG. 6B is 91%, the processor 300 can obtain the difference between the positive electrode final value and the positive electrode initial value (pf-pi) as 91%. Figure 10 In the voltage graph of FIG. 6B, when the capacity axis is expressed in % units, the x-coordinate value of the positive electrode final value pf can be considered as a value expressing the difference between the positive electrode final value and the positive electrode initial value (pf-pi) as a percentage. That is, when the x-coordinate value of the positive electrode final value pf in the voltage graph of FIG. 6B is 91%, the processor 300 can obtain the difference between the positive electrode final value and the positive electrode initial value (pf-pi) as 91%.

[0161] If the difference between the final value of the positive electrode and the initial value of the positive electrode (pf-pi) or the difference between the final value of the negative electrode and the initial value of the negative electrode (nf-ni) at a specific point in time is obtained as above, the processor 300 can calculate the capacity of the electrode at the corresponding point in time based on the difference. In particular, the positive electrode has a greater impact on the battery capacity than the negative electrode. Accordingly, the processor 300 can calculate the capacity of the target battery in the current state by using the following equation based on the difference between the final value of the positive electrode and the initial value of the positive electrode.

[0162] Capacity = a x PL x PA

[0163] Here, a is a value indicating the difference between the final value of the positive electrode and the initial value of the positive electrode (pf-pi), and can be expressed by converting a percentage (%) into a decimal unit. For example, when the difference between the final value of the positive electrode and the initial value of the positive electrode is 90%, a can be substituted as 0.9 in the equation.

[0164] In addition, PL indicates a loading value of an active material for the positive electrode, and can be expressed as a unit [mAh / cm 2 ] indicating a capacity ratio with respect to an area such as 3. In addition, PA indicates the total area of the positive electrode included in one battery, and can be expressed in a unit such as [cm 2 ].

[0165] The PL and PA values can be values previously stored in the storage unit 100. Accordingly, the processor 300 can access the storage unit 100 to read the PL and PA values. Furthermore, a can be obtained by the processor 300 as described above. Thus, if the values of a, PL, and PA are obtained in this way, the processor 300 can calculate the capacity of the target battery in the current state based on these values.

[0166] For example, when a is 0.9, PL is 3 [mAh / cm 2 ], and PA is 20,000 [cm 2 ], the processor 300 can estimate the capacity of the target battery by the following equation.

[0167] Capacity = 0.9 x 3 x 20,000 = 54,000 [mAh] = 54 [Ah]

[0168] In this case, the processor 300 can estimate the capacity of the target battery at the current cycle point as 54 [Ah].

[0169] Furthermore, the processor 300 can identify the capacity of the target battery using the value a (the difference between the final value of the positive electrode and the initial value of the positive electrode) at a plurality of different points in time. Thus, the processor 300 can estimate the capacity change of the target battery according to use by comparing the capacities determined at different cycle points with each other.

[0170] For example, if the capacity identified at the first cycle point is 55 Ah and the capacity identified at the second cycle point is 53 Ah, the processor 300 can estimate that the capacity of the target battery is decreased by 2 Ah due to the use between the first cycle point and the second cycle point.

[0171] In addition, if the capacity change of the target battery is estimated as described above, the processor 300 can compare the estimated capacity change amount with the standard change amount stored in the storage unit 100 or the like. If the estimated capacity change amount exceeds the standard change amount, the processor 300 can determine that the degree of deterioration of the target battery is severe. Also, if the estimated capacity change amount is lower than the standard change amount, the processor 300 can determine that the degree of deterioration of the target battery is not severe or is low.

[0172] For example, assuming that the standard change amount is 5 Ah every time 100 cycles elapse and 100 cycles elapse from the first cycle point to the second cycle point, if the capacity change amount estimated at the first cycle point and the capacity change amount estimated at the second cycle point exceed 5 Ah, the processor 300 can judge that the deterioration of the target battery is abnormal. Also, if the capacity change amount estimated at the first cycle point and the capacity change amount estimated at the second cycle point are 5 Ah or less, the processor 300 can judge that the deterioration of the target battery is normal.

[0173] According to this configuration of the present disclosure, the capacity change of the target battery can be verified more easily and simply.

[0174] In addition, the processor 300 can be configured to identify the change in the non-use region of the positive electrode or the negative electrode of the target battery based on the comparison result between the positive electrode adjustment curves or the comparison result between the negative electrode adjustment curves. This will be described in more detail with reference to Figure 11 and Figure 12 This will be described in more detail.

[0175] Figure 11 and Figure 12 is a graph comparatively showing the positive electrode adjustment curves and the negative electrode adjustment curves obtained by the processor 300 according to the embodiments of the present disclosure at different cycle points, and the positive electrode reference curve and the negative electrode reference curve.

[0176] First, reference will be made to Figure 11It can be considered that the curve Rp represents a positive electrode reference curve stored in the storage unit 100, and the curve Rn represents a negative electrode reference curve stored in the storage unit 100. Further, the curve Rp1' can be considered as a first positive electrode adjustment curve obtained in a process in which the processor 300 matches the analog curve R with the first charge and discharge measurement curve Ml as much as possible at the first cycle point. Further, the curve Rn1' can be considered as a first negative electrode adjustment curve obtained in a process in which the processor 300 matches the analog curve R with the first charge and discharge measurement curve Ml as much as possible at the first cycle point.

[0177] Next, referring to Figure 12 It can be considered that the curves Rp and Rn are the same as in Figure 11 Further, the curve Rp2' can be considered as a second positive electrode adjustment curve obtained in a process in which the processor 300 matches the analog curve R with the second charge and discharge measurement curve M2 as much as possible at the second cycle point. Further, the curve Rn2' can be considered as a second negative electrode adjustment curve obtained in a process in which the processor 300 matches the analog curve R with the second charge and discharge measurement curve M2 as much as possible at the second cycle point.

[0178] The processor 300 can identify the positive electrode non-use area at each cycle point in each of the first positive electrode adjustment curve Rp1' and the second positive electrode adjustment curve Rp2' by checking how much the point at which the capacity is 0 in the positive electrode reference curve Rp moves in the direction of the capacity axis (-x axis) in each graph of Figure 11 and Figure 12 Further, the processor 300 can identify the negative electrode non-use area at each cycle point in each of the first negative electrode adjustment curve Rn1' and the second negative electrode adjustment curve Rn2' by checking how much the point at which the capacity is 0 in the negative electrode reference curve Rn moves in the direction of the capacity axis (-x axis).

[0179] More specifically, in Figure 11 , it can be confirmed that the point at which the capacity is 0 in the positive electrode reference curve Rp moves by Gp1 in the left direction (-x axis direction) in the first positive electrode adjustment curve Rp1'. In this case, the processor 300 can judge that as much positive electrode non-use area as Gp1 [Ah] is generated in the target battery at the first cycle point. Further, it can be confirmed that the point at which the capacity is 0 in the negative electrode reference curve Rn moves by Gn1 to the left in the first negative electrode adjustment curve Rn1'. In this case, the processor 300 can judge that as much negative electrode non-use area as Gn1 [Ah] is generated in the target battery at the first cycle point.

[0180] Further, in Figure 12In the second positive electrode adjustment curve Rp2', it can be confirmed that the point with a capacity of 0 in the positive electrode reference curve Rp has shifted by Gp2 in the left direction (-x-axis direction). In this case, the processor 300 can determine that at the second cycle point, an amount of unused positive electrode region equal to Gp2[Ah] has been generated in the target battery. Similarly, in the second negative electrode adjustment curve Rn2', it can be confirmed that the point with a capacity of 0 in the negative electrode reference curve Rn has shifted by Gn2 to the left. In this case, the processor 300 can determine that at the second cycle point, an amount of unused negative electrode region equal to Gn2[Ah] has been generated in the target battery.

[0181] According to the configuration disclosed herein, by comparing the reference curve and the adjustment curve, the unused positive electrode area and the unused negative electrode area of ​​the target battery can be easily and accurately identified. Furthermore, according to this embodiment, the usable area of ​​the target battery can be easily identified.

[0182] Specifically, in the above configuration, the processor 300 can identify changes in the non-use area of ​​the positive electrode of the target battery by comparing the results between the positive electrode adjustment curves.

[0183] For example, the processor 300 can identify changes in the positive electrode unused region by the difference between Gp2, corresponding to the positive electrode unused region at the second loop point, and Gp1, corresponding to the positive electrode unused region at the first loop point. In this case, when the change in the positive electrode unused region is Gp, Gp can be represented as follows.

[0184] Gp = |Gp2 - Gp1|

[0185] Specifically, you can refer to Figure 13 To describe the content more clearly.

[0186] Figure 13 It shows Figure 11 The first positive electrode regulation curve Rp1' and depicted in the figure Figure 12 The second positive electrode regulation curve Rp2' depicted in the figure is integrated into an enlarged view of the non-use area of ​​the positive electrode in a single curve graph.

[0187] like Figure 13 As shown, compared to the first positive electrode adjustment curve Rp1', the second positive electrode adjustment curve Rp2' can be considered to have shifted in the -x-axis direction. Furthermore, the degree of shift can be represented by Gp. In this case, Gp can be considered equal to the absolute value of the difference between Gp2 and Gp1 (|Gp2-Gp1|).

[0188] The processor 300 can identify how the positive electrode non-use region of the target battery changes during the period from the first cycle point to the second cycle point by obtaining the Gp value in this way. Furthermore, as the battery deteriorates, in many cases, the positive electrode non-use region tends to increase due to loss of available lithium and the like, and thus the second positive electrode adjustment curve Rp2' moves to the left (-x-axis direction) compared to the first positive electrode adjustment curve Rp1'. Therefore, by comparing the degree of movement of the positive electrode adjustment curves at different cycle points by the processor 300, the degree of change in the positive electrode non-use region can be quantitatively identified.

[0189] In addition, the processor 300 can identify the degree of change in the negative electrode non-use region by comparing the negative electrode adjustment curves in a similar manner. That is, the processor 300 can quantitatively identify the degree of change in the negative electrode non-use region by comparing the degree of movement of the first negative electrode adjustment curve Rn1' and the second negative electrode adjustment curve Rn2' with each other.

[0190] The processor 300 can be configured to reduce the error with the charge and discharge measurement curves by moving the simulation curve R in parallel in the vertical direction at each of a plurality of different time points (e.g., at each of the first cycle point and the second cycle point). That is, even after performing adjustment such as movement and / or scaling with respect to the positive electrode reference curve Rp and / or the negative electrode reference curve Rn so that the adjusted simulation curve R' has a small error with the first charge and discharge measurement curve M1 or the second charge and discharge measurement curve M2 as described above, the processor 300 can move the adjusted simulation curve up or down in parallel to perform additional adjustment to further reduce the error. That is, the processor 300 can perform an auxiliary adjustment process of moving the simulation curve in the vertical direction again, which is first adjusted by movement and / or scaling with respect to the reference curve. It will be referred to as a "vertical direction auxiliary adjustment process" hereinafter. Figure 14 This will be described in more detail.

[0191] Figure 14 FIG. 13 is a graph schematically illustrating a configuration of moving the simulation curve R in the vertical direction in parallel by the processor according to an embodiment of the disclosure.

[0192] Referring to Figure 14 As described above, the simulation curve can be obtained mainly based on the positive electrode adjustment curve and the negative electrode adjustment curve. In addition, this is in Figure 14indicated by R1', and is referred to as a simulated main regulation curve. The simulated main regulation curve R1' can be obtained from the positive electrode main regulation curve and the negative electrode main regulation curve, which are obtained by moving in the horizontal direction, scaling (reducing), determining pi, pf, ni, nf, etc. with respect to the positive electrode reference curve and / or the negative electrode reference curve as described above. More specifically, the simulated main regulation curve R1' can be a full-cell voltage curve obtained from the difference between the positive electrode main regulation curve and the negative electrode main regulation curve.

[0193] That is, the simulated main regulation curve R1' can be regarded as a value that minimizes the error with the charge and discharge measurement curve M by adjustment of the positive electrode reference curve and / or the negative electrode reference curve. However, there can be a case where the error with the first charge and discharge measurement curve M1 or the second charge and discharge measurement curve M2 is further reduced by upward or downward movement (movement in the y-axis direction) of the simulated main regulation curve R1'. The processor 300 can be configured to search for a case where the error with the charge and discharge measurement curve M1 or M2 is reduced by moving the simulated main regulation curve R1' in the vertical direction in this way.

[0194] For example, the processor 300 can obtain a curve as indicated by R2' by moving the simulated main regulation curve R1' in the upward direction in parallel in the configuration of Figure 14 If the error with the charge and discharge measurement curve M1 or M2 is reduced in the curve R2' compared to the curve R1', the processor 300 can refer to the curve R2' as a simulated curve after auxiliary regulation, i.e., a simulated auxiliary regulation curve.

[0195] If the simulated auxiliary regulation curve R2' where the error with the charge and discharge measurement curve M1 or M2 is further reduced is searched for by moving the simulated main regulation curve R1' in the y-axis direction in parallel, the processor 300 can be configured to identify whether the internal resistance of the target battery is increased, taking into account the result of the parallel movement. That is, the processor 300 can identify the change in the internal resistance of the target battery at the corresponding time point based on how much the simulated auxiliary regulation curve R2' is moved upward from the simulated main regulation curve R1'. This will be described in more detail with reference to Figure 15 This will be described in more detail.

[0196] Figure 15 is an enlarged graph showing a part B1 of Figure 14 However, for convenience of explanation, in Figure 15 , the capacity axis and the voltage axis corresponding to the part B1 of Figure 14 are displayed together.

[0197] Referring to Figure 15The simulated auxiliary regulation curve R2' can be obtained by moving the simulated main regulation curve R1' in the arrow A7 direction (i.e., in the upward direction) in parallel. At this time, the degree of movement in the upward direction can be calculated as 4.120 - 4.104 = 0.016, and 0.016 [V] can be obtained. Thus, it can be considered that the processor 300 obtains the simulated auxiliary regulation curve R2' by moving the simulated main regulation curve R1' upward by 0.016 V (i.e., 16 mV).

[0198] In this case, the processor 300 can determine that 16 mV is the degree of voltage increase due to the increase in the internal resistance of the target battery, and 16 mV is the degree of parallel movement in the upward direction. That is, if the internal resistance of the secondary battery increases, this can cause the overvoltage to increase, and the processor 300 can identify how much the overvoltage of the target battery increases by adjusting the value through the parallel movement of the simulated curve. That is, in this embodiment, the processor 300 can determine that the internal resistance increases such that the overvoltage increases by 16 mV with respect to the target battery. In particular, when the simulated auxiliary regulation curve R2' is obtained by moving the simulated main regulation curve R1' upward, the processor 300 can determine that the internal resistance of the target battery increases. In addition, if the simulated auxiliary regulation curve R2' is obtained by moving the simulated main regulation curve R1' downward, the processor 300 can determine that the internal resistance of the target battery decreases.

[0199] In addition, when the voltage increases due to the increase in the internal resistance, the processor 300 can easily identify how much capacity is lost. In particular, the processor 300 can identify the capacity loss of the target battery through the capacity difference at the point at which the simulated main regulation curve R1' and the simulated auxiliary regulation curve R2' reach the preset end-of-charge voltage.

[0200] For example, in the embodiment of Figure 15 , when the end-of-charge voltage of the target battery is 4.2 V, the processor 300 can search for points at which the end-of-charge voltage becomes 4.2 V in the simulated main regulation curve R1' and the simulated auxiliary regulation curve R2', respectively. In Figure 15 , such points are denoted by Pr1 and Pr2, respectively. In addition, the processor 300 can confirm the capacity values of these points Pr1 and Pr2, respectively. In Figure 15 , it can be confirmed that the capacity value of Pr1 is 58 Ah, and the capacity value of Pr2 is 56 Ah. In this case, the processor 300 can determine 2 Ah, which is the difference between Pr1 and Pr2, as the capacity loss value according to the increase in the internal resistance of the target battery.

[0201] If in Figure 15In an embodiment in which the capacity axis (x-axis) is expressed in units of %, the processor 300 can directly extract the capacity loss value according to the increase in internal resistance in units of %. For example, if the x-coordinate value of Pr1 is 94% and the x-coordinate value of Pr2 is 93%, the processor 300 can calculate the capacity loss value according to the increase in internal resistance of the target battery at the corresponding point of time as 94-93=1, and thus determine the capacity loss value as 1%. Also, in this case, the processor 300 can predict that the target battery is turned off 1% early due to the increase in internal resistance at the corresponding cycle point.

[0202] According to this embodiment of the present disclosure, by adjusting the simulation curve, it can be easily determined whether the internal resistance of the target battery is increased and by how much the overvoltage is increased or how much the capacity is lost.

[0203] In particular, according to the embodiment of the present disclosure, the processes described in Figure 14 and Figure 15 may be performed with respect to the target battery at different cycle points, respectively. For example, at a first cycle point and a second cycle point having different cycle numbers, the configurations of moving the simulation curve in parallel in the vertical direction and calculating the overvoltage increase amount and the capacity loss value according to the internal resistance increase as a result of the movement as described in Figure 14 and Figure 15 may be performed, respectively. Also, the processor 300 can be configured to identify how much the internal resistance of the target battery is increased during a period between cycle points by comparing the magnitudes of the parallel movements with respect to a plurality of different cycle points. Furthermore, the processor 300 can compare the overvoltage increase amount and the capacity loss increase value of the target battery by comparing the results obtained at different cycle points with each other.

[0204] More specifically, if the simulation main adjustment curve is moved upward by 0.016V at a first cycle point to obtain a simulation auxiliary adjustment curve and the simulation main adjustment curve is moved upward by 0.030V at a second cycle point to obtain a simulation auxiliary adjustment curve, the processor 300 can calculate as follows.

[0205] 0.030-0.016=0.014

[0206] Accordingly, the processor 300 can determine that the voltage is increased by 0.014V, i.e., 14mV, due to the increase in internal resistance of the target battery during a use period from the first cycle point to the second cycle point. That is, the processor 300 can identify that the internal resistance of the target battery has increased to the extent that the voltage is increased by 14mV during the period between the first cycle point and the second cycle point.

[0207] In addition, if the capacity loss value obtained for the first cycle point is 2 Ah and the capacity loss value obtained for the second cycle point is 4 Ah, the processor 300 can calculate the capacity loss value of the target battery for the usage period from the first cycle point to the second cycle point as follows.

[0208] 4 - 2 = 2

[0209] Accordingly, the processor 300 can determine that the capacity loss of the target battery is further increased by 2 Ah during the usage period from the first cycle point to the second cycle point.

[0210] In particular, when it is desired to directly obtain the amount of voltage increase or the amount of capacity loss between a plurality of different time points (e.g., between the first cycle point and the second cycle point), the processor 300 can directly compare the auxiliary adjustment curve at the first cycle point with the auxiliary adjustment curve at the second cycle point. For example, in the embodiment of Equations Figure 14 and Figure 15 In this case, the processor 300 can immediately recognize the effect according to the increase in internal resistance between the first cycle point and the second cycle point.

[0211] The secondary battery diagnosis apparatus according to the present disclosure can be applied to a battery pack. That is, the battery pack according to the present disclosure can include the above-described secondary battery diagnosis apparatus according to the present disclosure. In addition, the battery pack according to the present disclosure can include components commonly included in a battery pack, such as one or more secondary batteries, a BMS (Battery Management System), a current sensor, a relay, a fuse, a battery pack housing, etc., in addition to the secondary battery diagnosis apparatus according to the present disclosure. In this case, the secondary battery included in the battery pack can be a target, i.e., a target battery, diagnosed by the secondary battery diagnosis apparatus according to the present disclosure. In addition, at least some components of the secondary battery diagnosis apparatus according to the present disclosure can be implemented as conventional components included in the battery pack. For example, the voltage measurement unit 200 of the secondary battery diagnosis apparatus according to the present disclosure can be implemented using a voltage sensor included in the battery pack. In addition, at least some functions or operations of the processor 300 of the secondary battery diagnosis apparatus according to the present disclosure can be implemented by the BMS included in the battery pack.

[0212] In addition, the secondary battery diagnosis device according to the present disclosure can be applied to a vehicle. That is, a vehicle according to the present disclosure can include the above-described secondary battery diagnosis device according to the present disclosure. In particular, in the case of an electric vehicle, a battery pack is a very important component as a driving source, and thus the secondary battery diagnosis device according to the present disclosure can be more usefully applied. In addition, the vehicle according to the present disclosure can include other various devices such as a vehicle body, a vehicle control unit such as an ECU, a motor, a connection terminal, a DC-DC converter, and the like, in addition to the secondary battery diagnosis device. In addition, the vehicle according to the present disclosure can also employ components that are generally included in a vehicle.

[0213] Figure 16 is a flowchart schematically illustrating a secondary battery diagnosis method according to an embodiment of the present disclosure. In Figure 16 each step can be performed by each component of the above-described secondary battery diagnosis device.

[0214] Referring to Figure 16 , the secondary battery diagnosis method according to the present disclosure includes a reference curve storage step (S110), a charge and discharge voltage measurement step (S120), a charge and discharge measurement curve generation step (S130), a simulated curve and charge and discharge measurement curve comparison step (S140), and a positive electrode adjustment curve and negative electrode adjustment curve determination step (S150).

[0215] Step S110 is a step of storing a positive electrode reference curve and a negative electrode reference curve of a reference battery for charging or discharging.

[0216] Step S120 is a step of measuring a voltage at the time of charging or discharging a target battery at each of a plurality of different time points (for example, at each of a first cycle point and a second cycle point).

[0217] Step S130 is a step of generating a charge and discharge measurement curve at each of a plurality of different time points based on the voltage measured in step S120.

[0218] Step S140 is a step of comparing a simulated curve obtained from the positive electrode reference curve and the negative electrode reference curve stored in step S110 with each charge and discharge measurement curve generated in step S130.

[0219] Step S150 is a step of determining a positive electrode adjustment curve and a negative electrode adjustment curve for each of a plurality of charge and discharge measurement curves such that an error between the simulated curve and the charge and discharge measurement curve is within a certain level when it is judged through the comparison in step S140 that there is an error of a certain level or higher between the simulated curve and the charge and discharge measurement curve.

[0220] For these steps S110 to S150, the above-described features of the secondary battery diagnosis device according to the present disclosure can be identically or similarly applied. Therefore, each step of the secondary battery diagnosis method according to the present disclosure will not be described in detail here.

[0221] The present disclosure has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the present disclosure, are given by way of illustration only, since various changes and modifications within the scope of the present disclosure will become apparent to those skilled in the art from this detailed description.

[0222] [Reference Signs]

[0223] 100: storage unit

[0224] 200: voltage measurement unit

[0225] 300: processor

[0226] Rp: positive electrode reference curve

[0227] Rn: negative electrode reference curve

[0228] M1: first charge and discharge measurement curve

[0229] M2: second charge and discharge measurement curve

[0230] Rp': positive electrode adjustment curve

[0231] Rn': negative electrode adjustment curve

Claims

1. A secondary battery diagnostic apparatus comprising: a storage unit configured to store a positive electrode reference curve and a negative electrode reference curve for charging or discharging of a reference battery, wherein the positive electrode reference curve and the negative electrode reference curve are curves indicating a positive electrode voltage for each capacity and a negative electrode voltage for each capacity, respectively; a voltage measurement unit configured to measure a voltage of a target battery during a charging or discharging process; and a processor configured to: generate a plurality of charging and discharging measurement curves based on the voltage measured by the voltage measurement unit at a plurality of different time points during the charging or discharging process, compare each of the generated plurality of charging and discharging measurement curves with an analog curve obtained from the positive electrode reference curve and the negative electrode reference curve stored in the storage unit, and determine a positive electrode adjustment curve and a negative electrode adjustment curve for each of the generated plurality of charging and discharging measurement curves such that an error between each of the charging and discharging measurement curves and the analog curve is within a predetermined level.

2. The secondary battery diagnostic device according to claim 1, wherein The processor determines an adjustment value of the positive electrode reference curve and an adjustment value of the negative electrode reference curve in a case where an error between the analog curve and the charging and discharging measurement curves is minimum, as the positive electrode adjustment curve and the negative electrode adjustment curve, respectively. 3.The secondary battery diagnostic apparatus of claim 1, wherein the processor is configured to compare the positive electrode adjustment curves or the negative electrode adjustment curves determined at the plurality of different time points. 4.The secondary battery diagnostic apparatus of claim 3, wherein, the processor is configured to identify a change in a non-use region of a positive electrode or a negative electrode of the target battery based on a comparison result between the positive electrode adjustment curves or a comparison result between the negative electrode adjustment curves. 5.The secondary battery diagnostic apparatus of claim 1, wherein the processor is configured to determine the positive electrode adjustment curve and the negative electrode adjustment curve by moving at least one of the positive electrode reference curve and the negative electrode reference curve in a horizontal direction. 6.The secondary battery diagnostic apparatus of claim 1, wherein the processor is configured to determine the positive electrode adjustment curve and the negative electrode adjustment curve by adjusting a ratio of at least one of the positive electrode reference curve and the negative electrode reference curve in a horizontal direction. 7.The secondary battery diagnostic apparatus of claim 1, wherein the voltage measurement unit is configured to measure a fully discharged voltage and a fully charged voltage of the target battery, and the processor is configured to estimate a positive electrode initial value of the positive electrode adjustment curve or a negative electrode initial value of the negative electrode adjustment curve based on the fully discharged voltage, and estimate a positive electrode final value of the positive electrode adjustment curve and a negative electrode final value of the negative electrode adjustment curve based on the fully charged voltage. 8.The secondary battery diagnostic apparatus of claim 7, wherein, The processor is configured to identify the capacity of the target battery at each time point based on a difference between the positive electrode final value and the positive electrode initial value or a difference between the negative electrode final value and the negative electrode initial value.

9. The secondary battery diagnostic device according to claim 1, wherein The processor is configured to reduce an error between the simulation curve and the charge and discharge measurement curve by moving the simulation curve in a vertical direction in parallel at each of the plurality of different time points, and to identify how much the internal resistance of the target battery increases at the plurality of different time points by comparing a magnitude of the parallel movement at each of the plurality of different time points.

10. A battery pack including the secondary battery diagnostic device according to any one of claims 1 to 9.

11. A vehicle including the secondary battery diagnostic device according to any one of claims 1 to 9.

12. A secondary battery diagnostic method including the steps of: storing a positive electrode reference curve and a negative electrode reference curve for charging or discharging of a reference battery, wherein the positive electrode reference curve and the negative electrode reference curve are curves indicating a positive electrode voltage for each capacity and a negative electrode voltage for each capacity, respectively; measuring a voltage of a target battery at each of a plurality of different time points while charging or discharging the target battery; generating a charge and discharge measurement curve at each of the plurality of different time points based on the voltage measured in the voltage measurement step during the charging process or the discharging process; comparing a simulation curve obtained from the positive electrode reference curve and the negative electrode reference curve stored in the storing step with each charge and discharge measurement curve generated in the generating step; and determining a positive electrode adjustment curve and a negative electrode adjustment curve for each of a plurality of charge and discharge measurement curves such that an error between the simulation curve and the charge and discharge measurement curve is within a predetermined level.

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