Apparatus and method for estimating soh

Abstract

A SOH estimation device according to one embodiment of the present invention includes: a profile acquisition unit configured to acquire OCV profiles for a plurality of OCVs of a battery measured at different points in time; a profile correction unit configured to generate an adjusted positive profile and an adjusted negative profile by adjusting a preset reference positive profile and a reference negative profile to correspond to the OCV profiles; and a control unit configured to extract a diagnostic factor for the battery from the adjusted positive profile or the adjusted negative profile and to estimate the capacity SOH of the battery based on the extracted diagnostic factor.

Description

Technology Field

[0001] This application is a priority claim application for Korean Patent Application No. 10-2023-0115876 filed on August 31, 2023, and all contents disclosed in the specification and drawings of said application are incorporated into this application by reference.

[0002] The present invention relates to a State of Health (SOH) estimation apparatus and method, and more specifically, to a SOH estimation apparatus and method for estimating the SOH of a battery using Open Circuit Voltage (OCV). Background Technology

[0003] Recently, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has increased rapidly, and the development of electric vehicles, energy storage batteries, robots, and satellites has accelerated, research on high-performance batteries capable of repeated charging and discharging is actively underway.

[0004] Currently commercialized batteries include nickel-cadmium, nickel-hydrogen, nickel-zinc, and lithium batteries. Among these, lithium batteries are gaining attention for their advantages, such as the ability to freely charge and discharge with almost no memory effect compared to nickel-based batteries, a very low self-discharge rate, and high energy density.

[0005] While much research is being conducted on these batteries in terms of increasing capacity and density, improving lifespan and safety is also important. To enhance battery safety, technology capable of accurately diagnosing the battery's current state is required.

[0006] Conventionally, the condition of a battery was diagnosed by analyzing a battery profile that represents the correspondence between the battery's capacity and voltage. For example, capacity and voltage were measured during the charging process, and the battery's condition was diagnosed through the analysis of the battery profile representing the correspondence between the measured capacity and voltage. As another example, the battery's condition may also be diagnosed based on the capacity and voltage measured during the discharge process.

[0007] Here, in order to diagnose the current state of the battery more accurately, a battery profile that accurately reflects the current state of the battery is required. However, there is a problem in that low-rate charging and discharging, such as 0.05C (C-rate), is required to obtain such a battery profile. That is, conventionally, low-rate charging and discharging was required to diagnose the state of the battery, so there were limitations in diagnosing the state of the battery. For example, since it takes about 20 hours for the battery to be fully charged at 0.05C, there is a problem in that a considerable amount of time is required to diagnose the state of the battery according to conventional low-rate charging and discharging. Patent Document 1 (KR 10-2022-0094042 A, July 5, 2022) discloses a configuration for measuring the closed-circuit voltage (CCV) of a target battery during the charging or discharging process. The problem to be solved

[0008] The present invention was devised to solve the above-mentioned problems and aims to provide an SOH estimation apparatus and method for estimating the SOH of a battery using OCV.

[0009] Other objects and advantages of the present invention may be understood from the following description and will become more clearly apparent from the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims. means of solving the problem

[0010] A SOH estimation device according to one aspect of the present invention may include: a profile acquisition unit configured to acquire OCV profiles for a plurality of OCVs of a battery measured at different points in time; a profile correction unit configured to generate an adjusted positive profile and an adjusted negative profile by adjusting a preset reference positive profile and a reference negative profile to correspond to the OCV profiles; and a control unit configured to extract a diagnostic factor for the battery from the adjusted positive profile or the adjusted negative profile and to estimate the capacity SOH of the battery based on the extracted diagnostic factor.

[0011] The plurality of OCVs may be configured to include an OCV measured at the time when the battery transitions from a resting state to a discharge state, and an OCV measured while the state in which the discharge current of the battery is below a preset threshold current is maintained for a preset reference time or longer.

[0012] The above plurality of OCVs may be configured to include a plurality of OCVs measured within a preset reference period.

[0013] The above reference period may be set as a preset target period, a period required to measure a preset number of OCVs, a period required for the SOH of the battery to decrease by a preset reference SOH, or a period based on a combination thereof.

[0014] The above profile correction unit may be configured to generate a comparison full cell profile based on the reference anode profile and the reference cathode profile, and to generate the adjustment anode profile and the adjustment cathode profile by adjusting the reference anode profile and the reference cathode profile until the generated comparison full cell profile corresponds to the OCV profile.

[0015] The above profile correction unit may be configured to determine a target capacity range corresponding to the OCV profile and to compare the comparison full cell profile and the OCV profile within the target capacity range.

[0016] The above control unit may be configured to estimate the capacity SOH of the battery by comparing a preset reference value for the diagnostic factor with the value of the diagnostic factor.

[0017] The above control unit may be configured to adjust the usage conditions for the battery based on the estimated capacity SOH.

[0018] A battery pack according to another aspect of the present invention may include an SOH estimation device according to one aspect of the present invention.

[0019] An automobile according to another aspect of the present invention may include an SOH estimation device according to one aspect of the present invention.

[0020] A server according to another aspect of the present invention may include an SOH estimation device according to one aspect of the present invention.

[0021] A method for estimating SOH according to another aspect of the present invention may include: a profile acquisition step of acquiring OCV profiles for a plurality of OCVs of a battery measured at different points in time; a profile adjustment step of adjusting a preset reference positive profile and a reference negative profile to correspond to the OCV profiles to generate an adjusted positive profile and an adjusted negative profile; a diagnostic factor extraction step of extracting a diagnostic factor for the battery from the adjusted positive profile or the adjusted negative profile; and a SOH estimation step of estimating the capacity SOH of the battery based on the extracted diagnostic factor. Effects of the invention

[0022] According to one aspect of the present invention, since the SOH estimation device estimates the SOH of a battery using an OCV profile, there is an advantage that charging and discharging of the battery is not required to obtain the battery profile. That is, according to the present invention, charging and discharging of the battery is not required in the process of estimating the SOH of the battery. Therefore, compared to conventional methods in which a battery profile must be obtained during the charging and discharging process to estimate the SOH of the battery, the present invention has the advantage of being able to quickly estimate the SOH of the battery based on an OCV profile.

[0023] In addition, according to one aspect of the present invention, the SOH estimation device has the advantage of being able to diagnose the state of a battery from various perspectives based on the types of extractable diagnostic factors.

[0024] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims. Brief explanation of the drawing

[0025] The following drawings attached to this specification serve to further enhance understanding of the technical concept of the invention in conjunction with the detailed description of the invention set forth below; therefore, the invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a schematic diagram illustrating an SOH estimation device according to one embodiment of the present invention. FIG. 2 is a schematic diagram illustrating an OCV profile according to an embodiment of the present invention. FIG. 3 is a diagram illustrating the measured OCV of a battery according to one embodiment of the present invention. FIG. 4 is a schematic diagram illustrating a reference anode profile and a reference cathode profile according to an embodiment of the present invention. FIG. 5 is a schematic diagram illustrating a comparative full-cell profile according to one embodiment of the present invention. FIG. 6 is a schematic diagram illustrating a comparative full-cell profile and an OCV profile according to one embodiment of the present invention. FIGS. 7 to 14 are drawings for explaining the process of adjusting a reference anode profile and a reference cathode profile according to an embodiment of the present invention. FIG. 15 is a drawing illustrating an exemplary configuration of a battery pack according to another embodiment of the present invention. FIG. 16 is a drawing illustrating an exemplary configuration of a vehicle according to another embodiment of the present invention. FIG. 17 is a schematic diagram illustrating a method for estimating SOH according to another embodiment of the present invention. Specific details for implementing the invention

[0026] Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0027] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0028] In addition, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the invention, such detailed description is omitted.

[0029] Terms including ordinal numbers, such as first, second, etc., are used for the purpose of distinguishing one of the various components from the rest, and are not used to limit the components by such terms.

[0030] Throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0031] Additionally, throughout the specification, when it is said that a part is "connected" to another part, this includes not only cases where they are "directly connected," but also cases where they are "indirectly connected" with other components in between.

[0033] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0034] FIG. 1 is a schematic diagram illustrating a State of Health (SOH) estimation device (100) according to one embodiment of the present invention.

[0035] Referring to FIG. 1, the SOH estimation device (100) may include a profile acquisition unit (110), a profile correction unit (120), and a control unit (130).

[0036] The profile acquisition unit (110) may be configured to acquire OCV profiles (Rocv) for multiple OCVs (Open circuit voltages) of the battery measured at different points in time.

[0037] Here, a battery refers to a single, independent cell that is physically separable and equipped with a negative terminal and a positive terminal. For example, a lithium-ion battery or a lithium-polymer battery may be considered a battery. Additionally, the battery may be of the cylindrical, prismatic, or pouch type. Furthermore, a battery may refer to a battery bank, battery module, or battery pack in which multiple cells are connected in series and / or parallel. For the sake of convenience of explanation, the term "battery" below is described as referring to a single, independent cell.

[0038] Here, the OCV profile (Rocv) is a profile representing the correspondence between the OCV and capacity of the battery. Specifically, the OCV of the battery can be measured at a point in time when certain conditions are satisfied. More specifically, a plurality of OCVs may be configured to include the OCV measured at the point when the battery transitions from a resting state to a discharge state, and the OCV measured while the state in which the discharge current of the battery is below a preset threshold current is maintained for a preset reference time or longer.

[0039] First, the battery's OCV can be measured at the point when the battery transitions from a resting state to a discharged state. Here, a resting state refers to a stabilized state where the battery is maintained in a no-load state for a certain period of time or longer. For example, if the battery is included in a vehicle, the battery's OCV can be measured at the key-on point when the engine of a vehicle parked for a certain period of time or longer is turned on. Additionally, the battery's capacity can be determined based on the capacity at the key-off point when the engine of the vehicle is turned off.

[0040] Next, the battery's OCV can be measured while the state in which the battery's discharge current is below a preset threshold current is maintained for a preset reference time or longer. Here, the state in which the battery's discharge current is below the threshold current refers to a state where the amount of battery discharge can be ignored. In other words, if the battery is in a discharged state but the amount of discharge is negligible, the measured battery voltage can be estimated as the OCV. This is because, if the amount of battery discharge is at a negligible level, the battery can be considered to be in a stabilized state even if it is discharging for a reference time or longer. For example, if a battery is included in a vehicle and the vehicle is stationary for a reference time or longer, the battery may continuously discharge to supply power to electrical components. However, the amount of battery discharge required to supply power to electrical components is very negligible relative to the battery's capacity. Therefore, although the battery is actually in a discharged state, the battery voltage can be estimated as the OCV.

[0041] FIG. 2 is a schematic diagram illustrating an OCV profile (Rocv) according to an embodiment of the present invention. Referring to FIG. 2, the OCV profile (Rocv) represents the correspondence between the OCV and capacity of a battery in a capacity range of 10 (Ah) or more and 45 (Ah) or less. As previously explained, since the conditions under which the OCV can be measured are limited, the multiple OCVs included in the OCV profile (Rocv) may be discontinuous.

[0042] For example, the profile acquisition unit (110) can directly receive an OCV profile (Rocv) from the outside. That is, the profile acquisition unit (110) can acquire an OCV profile (Rocv) by receiving an OCV profile (Rocv) through a wired and / or wireless connection to the outside.

[0043] As another example, the profile acquisition unit (110) can receive battery information regarding the OCV (V) and capacity (Q) of the battery. Then, the profile acquisition unit (110) can generate an OCV profile (Rocv) based on the received battery information. That is, the profile acquisition unit (110) can acquire an OCV profile (Rocv) by directly generating an OCV profile (Rocv) based on the battery information.

[0044] The profile acquisition unit (110) can be connected to communicate with the profile correction unit (120). For example, the profile acquisition unit (110) can be connected to the profile correction unit (120) via wired and / or wireless connections. The profile acquisition unit can transmit the acquired OCV profile (Rocv) to the profile correction unit (120).

[0045] The profile correction unit (120) may be configured to generate an adjusted anode profile and an adjusted cathode profile by adjusting the preset reference anode profile (Rp) and reference cathode profile (Rn) to correspond to the OCV profile (Rocv).

[0046] A reference positive profile (Rp) may be a profile representing the correspondence between the capacity and OCV of a reference positive cell that is preset to correspond to the positive of the battery. For example, the reference positive cell may be the positive of a positive coin half cell or a three-electrode cell. And, a reference negative profile (Rn) may be a profile representing the correspondence between the capacity and OCV of a reference negative cell that is preset to correspond to the negative of the battery. For example, the reference negative cell may be the negative of a negative coin half cell or a three-electrode cell.

[0047] Specifically, the profile correction unit (120) can adjust the reference anode profile (Rp) and the reference cathode profile (Rn) to correspond to the OCV profile (Rocv). More specifically, the profile correction unit (120) can generate an adjusted anode profile and an adjusted cathode profile by adjusting the reference anode profile (Rp) and the reference cathode profile (Rn). Then, the profile correction unit (120) can generate a comparison full cell profile (S) from the adjusted anode profile and the adjusted cathode profile. The profile correction unit (120) can adjust the reference anode profile (Rp) and the reference cathode profile (Rn) until the comparison full cell profile (S) corresponds to the OCV profile (Rocv). Here, the target capacity range (T) of the OCV profile (Rocv) may be different from the capacity range of the comparison full cell profile (S). Accordingly, the reference anode profile (Rp) and the reference cathode profile (Rn) can be adjusted depending on whether the comparison full cell profile (S) and the OCV profile (Rocv) correspond in the target capacity range (T).

[0048] For example, the profile correction unit (120) can generate a plurality of comparison full cell profiles (S) by shifting the reference anode profile (Rp) and the reference cathode profile (Rn) or by capacity scaling, and can identify a comparison full cell profile (S) among the plurality of comparison full cell profiles (S) that minimizes the error with the OCV profile (Rocv). Then, an adjusted anode profile and an adjusted cathode profile corresponding to the identified comparison full cell profile (S) can be determined.

[0049] In this regard, a more specific embodiment in which the profile correction unit (120) adjusts the reference positive profile (Rp) and the reference negative profile (Rn) to correspond to the OCV profile (Rocv) to determine the positive profile of the battery will be described later with reference to FIGS. 7 to 14.

[0050] The control unit (130) may be configured to extract diagnostic factors regarding the negative participation start point and negative participation end point for the battery in the adjustment negative profile.

[0051] Specifically, the control unit (130) can determine the cathode participation start point (ni) and the cathode participation end point (nf) in the adjusted cathode profile. The control unit (130) can determine the potential value or SOC value corresponding to the cathode participation start point (ni) in the adjusted cathode profile as the value of the cathode participation start point (ni). And, the control unit (130) can determine the potential value or SOC value corresponding to the cathode participation end point (nf) in the adjusted cathode profile as the value of the cathode participation end point (nf).

[0052] The control unit (130) can be configured to estimate the capacity SOH of the battery based on the extracted diagnostic factors.

[0053] Specifically, the control unit (130) may be configured to estimate the capacity SOH of the battery by comparing a preset reference value for the diagnostic factor with the value of the diagnostic factor.

[0054] Here, the preset reference value may be a value obtained in advance for a battery in the BOL (Beginning of Life) state. Preferably, the OCV profile (Rocv) for the battery in the BOL state may represent the correspondence between OCV and capacity for the entire capacity range. The control unit (130) may determine a reference value corresponding to the extracted diagnostic factor from the OCV profile (Rocv) for the battery in the BOL state. That is, the reference value is a state value for the battery in the BOL state, and the diagnostic factor is a state value for the battery in the current state. Accordingly, the control unit (130) can estimate the SOH of the battery based on the diagnostic factor representing the current state of the battery and the reference value representing the BOL state of the battery.

[0055] A SOH estimation device (100) according to one embodiment of the present invention can estimate the SOH of a battery based on the OCV of the battery measured under predetermined conditions. That is, according to the present invention, there is an advantage that low-rate charging and discharging for SOH estimation is not forced.

[0056] For example, if low-rate charging and discharging at 0.05C must be performed to estimate SOH, the battery's use may be restricted for about 20 hours. In contrast, the SOH estimation device (100) can estimate the battery's SOH by securing only an OCV profile (Rocv) that includes multiple OCVs. Furthermore, the conditions under which the OCV is measured are conditions under which the battery's use is not forcibly restricted. Therefore, since the SOH estimation device (100) can quickly estimate the battery's SOH based on the OCV profile (Rocv) without restricting the battery's use, it has the advantage of solving the conventional problem where the battery's use must be excessively restricted to estimate SOH.

[0058] Meanwhile, the control unit (130) provided in the SOH estimation device (100) may optionally include a processor, an ASIC (application-specific integrated circuit), another chipset, a logic circuit, a register, a communication modem, a data processing device, etc., known in the art, to execute various control logics performed in the present invention. Additionally, when the control logic is implemented in software, the control unit (130) may be implemented as a set of program modules. In this case, the program modules may be stored in memory and executed by the control unit (130). The memory may be located inside or outside the control unit (130) and may be connected to the control unit (130) by various well-known means.

[0059] Additionally, the SOH estimation device (100) may further include a storage unit (140). The storage unit (140) may store data or programs necessary for each component of the SOH estimation device (100) to perform operations and functions, or data generated during the process of performing operations and functions. The storage unit (140) is not subject to any special restrictions on its type as long as it is a known information storage means capable of recording, erasing, updating, and reading data. As an example, the information storage means may include RAM, flash memory, ROM, EEPROM, registers, etc. Additionally, the storage unit (140) may store program codes in which processes executable by the control unit (130) are defined.

[0060] For example, the storage unit (140) can store an OCV profile (Rocv), a reference anode profile (Rp), a reference cathode profile (Rn), an adjusted anode profile, an adjusted cathode profile, and diagnostic factors, etc.

[0062] Multiple OCVs may be configured to include multiple OCVs measured within a preset reference period.

[0063] Specifically, the measurement conditions for OCV may be limited. That is, the time at which multiple OCVs are measured may be non-periodic. For example, assume that a vehicle is started only once a day and that the vehicle's stopping time during operation is less than a reference time. In this case, since OCV is measured only at the time the vehicle is started, only one OCV may be measured per day. Therefore, multiple OCVs included in the OCV profile (Rocv) may be values ​​measured with a time difference of one day.

[0064] Considering these OCV measurement conditions, grouping conditions for multiple OCVs used to estimate the battery's SOH are necessary. That is, if the battery's SOH is estimated using multiple OCVs acquired over an excessively long period, the estimated battery's SOH may not be accurate because the battery may degrade further during that period. Therefore, the OCV profile (Rocv) may include only multiple OCVs measured within a preset reference period. Preferably, the reference period may be set experimentally or theoretically, or may be set by considering the operating pattern of the battery (e.g., driving pattern or charge / discharge pattern).

[0065] In one embodiment, the reference period may be set to a preset target period. For example, the OCV profile (Rocv) may include multiple OCVs measured within a recent two-week period. Accordingly, the SOH estimated based on the OCV profile (Rocv) containing only multiple OCVs measured within the reference period can accurately reflect the current state of the battery.

[0066] FIG. 3 is a diagram illustrating the measured OCV of a battery according to one embodiment of the present invention.

[0067] For example, in the embodiment of FIG. 3, the first to fifth periods (P1, P2, P3, P4, P5) may be shorter than a preset reference period. Accordingly, the SOH estimation device (100) can continuously diagnose the state of the battery by estimating the SOH of the battery based on the OCV profile (Rocv) for each of the first to fifth periods (P1, P2, P3, P4, P5).

[0068] In another embodiment, the reference period may be set as the time required to measure a preset number of OCVs. For example, the clarity or accuracy of the OCV profile (Rocv) is proportional to the number of OCVs measured. That is, as the number of measured OCVs increases, the OCV profile (Rocv) becomes clearer, so the result of adjusting the reference positive profile (Rp) and the reference negative profile (Rn) can better reflect the current state of the battery. Therefore, the period until a preset number (e.g., 30) of non-overlapping OCVs are measured may be preset as the reference period.

[0069] In another embodiment, the reference period may be set as the time required for the battery's SOH to decrease by a preset reference SOH. For example, when the frequency of OCV measurements is low, there is a problem in that multiple OCVs included in the OCV profile (Rocv) are measured at different SOHs. In this case, the result of adjusting the reference positive profile (Rp) and reference negative profile (Rn) based on the OCV profile (Rocv) results in a problem in that it reflects the battery's past state. Therefore, the period until the battery's SOH decreases by a preset reference SOH (e.g., 0.1%) may be preset as the reference period.

[0070] In another embodiment, the reference period may be set to the shortest period among a preset target period, a preset number of OCVs, and a preset reference period for the battery's SOH to decrease by a preset reference SOH.

[0071] Although limited embodiments regarding the reference period have been described above, it should be noted that the reference period for generating an appropriate OCV profile (Rocv) used to diagnose the current state of the battery can be set by considering various aspects.

[0072] The SOH estimation device (100) according to the present invention has the advantage of being able to more accurately estimate the SOH of a battery by limiting the measurement time of a plurality of OCVs used for SOH estimation.

[0074] Below, an embodiment in which the profile correction unit (120) adjusts the reference anode profile (Rp) and the reference cathode profile (Rn) is described in detail.

[0075] The profile correction unit (120) can be configured to generate a comparison full cell profile (S) based on a reference anode profile (Rp) and a reference cathode profile (Rn).

[0076] Specifically, a comparison full cell profile (S) can be generated based on the voltage difference (specifically, the OCV difference) for each capacity of the reference anode profile (Rp) and the reference cathode profile (Rn). For example, it is assumed that the voltage of the reference anode profile (Rp) corresponding to any capacity x is Vp and the voltage of the reference cathode profile (Rn) is Vn. The voltage of the comparison full cell profile (S) corresponding to capacity X can be calculated as "Vp-Vn". The profile correction unit (120) can generate the comparison full cell profile (S) by calculating the voltage difference between the reference anode profile (Rp) and the reference cathode profile (Rn) for the total capacity.

[0077] FIG. 4 is a schematic diagram illustrating a reference anode profile (Rp) and a reference cathode profile (Rn) according to an embodiment of the present invention. FIG. 5 is a schematic diagram illustrating a comparative full cell profile (S) according to an embodiment of the present invention. In the embodiments of FIG. 4 and FIG. 5, a comparative full cell profile (S) can be generated based on the voltage difference by capacity between the reference anode profile (Rp) and the reference cathode profile (Rn).

[0078] The profile correction unit (120) may be configured to generate an adjusted positive profile and an adjusted negative profile by adjusting the reference positive profile (Rp) and the reference negative profile (Rn) until the generated comparison full cell profile (S) corresponds to the OCV profile (Rocv).

[0079] Specifically, the profile correction unit (120) can calculate the error between the comparison full cell profile (S) and the OCV profile (Rocv). Then, the profile correction unit (120) can adjust the reference positive profile (Rp) and the reference negative profile (Rn) until the error between the comparison full cell profile (S) and the OCV profile (Rocv) is minimized. When the comparison full cell profile (S) that minimizes the error with the OCV profile (Rocv) is determined, the adjusted positive profile and the adjusted negative profile that form the basis of the determined comparison full cell profile (S) can be estimated as the positive profile and negative profile representing the current state of the battery. With current technology, there is a problem in that the positive profile and negative profile representing the current state of the battery cannot be directly obtained without directly disassembling the battery. Therefore, the adjusted positive profile and the adjusted negative profile that form the basis of the comparison full cell profile (S) determined through the adjustment process can be strongly estimated as the positive profile and negative profile that reflect the current state of the battery.

[0080] FIG. 6 is a schematic diagram illustrating a comparison full cell profile (S) and an OCV profile (Rocv) according to an embodiment of the present invention. In the embodiment of FIG. 6, the profile correction unit (120) can calculate an error between the two profiles based on the voltage difference per capacity between the comparison full cell profile (S) and the OCV profile (Rocv). Additionally, the profile correction unit (120) can determine the comparison full cell profile (S) in which the calculated error is minimized.

[0081] Preferably, the profile correction unit (120) may be configured to determine a target capacity range (T) corresponding to the OCV profile (Rocv).

[0082] For example, in the embodiment of FIG. 6, since the plurality of OCVs included in the OCV profile (Rocv) are measured non-periodically, a correspondence between OCV and capacity may appear only in the target capacity range (T). That is, the target capacity range (T) is the capacity range of the OCV profile (Rocv). Therefore, the profile correction unit (120) can first determine the target capacity range (T) based on the OCV profile (Rocv). For example, in the embodiment of FIG. 6, the target capacity range (T) may be determined as a capacity range of 10[Ah] or more and 45[Ah] or less.

[0083] The profile correction unit (120) can be configured to compare the comparison full cell profile (S) and the OCV profile (Rocv) in the target capacity range (T).

[0084] Specifically, since the comparison full cell profile (S) is generated based on the reference anode profile (Rp) and the reference cathode profile (Rn), it can represent the correspondence between voltage and capacity for the entire capacity range. In contrast, the OCV profile (Rocv) represents the correspondence between OCV and capacity for the target capacity range (T). Therefore, the profile correction unit (120) can compare the two profiles only for the target capacity range (T), which is the common capacity range of the comparison full cell profile (S) and the OCV profile (Rocv).

[0085] For example, in the embodiment of FIG. 6, the profile correction unit (120) can compare the comparison full cell profile (S) and the OCV profile (Rocv) in the target capacity range (T). And, the profile correction unit (120) can further adjust the reference anode profile (Rp) and the reference cathode profile (Rn) according to the comparison result.

[0087] Below, the diagnostic factors that the control unit (130) can select from the adjusted positive profile and / or adjusted negative profile are described in detail.

[0088] The control unit (130) may be configured to extract at least one of an anode factor based on an adjusted anode profile and a cathode factor based on an adjusted cathode profile as a diagnostic factor.

[0089] Here, the adjusted positive profile is the result of adjusting the reference positive profile (Rp), and the adjusted negative profile is the result of adjusting the reference negative profile (Rn). Specifically, as previously described, the profile correction unit (120) can adjust the reference positive profile (Rp) and the reference negative profile (Rn) so that the comparison full cell profile (S) corresponds to the OCV profile (Rocv).

[0090] The anode factor may be configured to include at least one of the anode participation initiation point (pi), anode participation endpoint (pf), and anode change rate (ps) of the battery based on the adjusted anode profile.

[0091] The anode participation initiation point (pi) may be a point corresponding to the starting capacity (lower limit capacity) of the target capacity range (T) in the adjusted anode profile. For example, in the embodiment of FIG. 6, since the starting capacity of the target capacity range (T) is 10 (Ah), the point where the capacity value is 10 (Ah) in the adjusted anode profile may be the anode participation initiation point (pi). Also, the value of the anode participation initiation point (pi) may be a potential value or SOC (State of charge) value corresponding to the anode participation initiation point (pi) in the adjusted anode profile.

[0092] The anode participation endpoint (pf) may be a point corresponding to the end capacity (upper capacity) of the target capacity range (T) in the adjusted anode profile. For example, in the embodiment of FIG. 6, since the end capacity of the target capacity range (T) is 45 (Ah), the point where the capacity value is 45 (Ah) in the adjusted anode profile may be the anode participation endpoint (pf). Also, the value of the anode participation endpoint (pf) may be a potential value or SOC value corresponding to the anode participation endpoint (pf) in the adjusted anode profile.

[0093] The anode change ratio (ps) may refer to the ratio of change [%] of the adjusted anode profile to the reference anode profile (Rp). Specifically, the anode change ratio (ps) may be the shrinkage ratio or expansion ratio of the adjusted anode profile to the reference anode profile (Rp). For example, if the adjusted anode profile is 10% shrunk from the reference anode profile (Rp), the anode change ratio (ps) is 90%. Conversely, if the adjusted anode profile is 10% expanded from the reference anode profile (Rp), the anode change ratio (ps) is 110%.

[0094] The cathode factor may be configured to include at least one of the cathode participation initiation point (ni), cathode participation end point (nf), and cathode change rate (ns) of the battery based on the adjusted cathode profile.

[0095] The cathode participation initiation point (ni) may be a point corresponding to the starting capacity (lower limit capacity) of the target capacity range (T) in the adjusted cathode profile. For example, in the embodiment of FIG. 6, since the starting capacity of the target capacity range (T) is 10 (Ah), the point where the capacity value is 10 (Ah) in the adjusted cathode profile may be the cathode participation initiation point (ni). Also, the value of the cathode participation initiation point (ni) may be a potential value or SOC value corresponding to the cathode participation initiation point (ni) in the adjusted cathode profile.

[0096] The cathode participation endpoint (nf) may be a point corresponding to the end capacity (upper capacity) of the target capacity range (T) in the adjusted cathode profile. For example, in the embodiment of FIG. 6, since the end capacity of the target capacity range (T) is 45 (Ah), the point where the capacity value is 45 (Ah) in the adjusted cathode profile may be the cathode participation endpoint (nf). Also, the value of the cathode participation endpoint (nf) may be a potential value or SOC value corresponding to the cathode participation endpoint (nf) in the adjusted cathode profile.

[0097] The cathode change ratio (ns) may refer to the ratio of change [%] of the adjusted cathode profile to the reference cathode profile (Rn). Specifically, the cathode change ratio (ns) may be the shrinkage ratio or expansion ratio of the adjusted cathode profile to the reference cathode profile (Rn). For example, if the adjusted cathode profile is 10% shrunk from the reference cathode profile (Rn), the cathode change ratio (ns) is 90%. Conversely, if the adjusted cathode profile is 10% expanded from the reference cathode profile (Rn), the cathode change ratio (ns) is 110%.

[0099] The control unit (130) may be configured to estimate at least one of the positive SOH, negative SOH, available lithium SOH, and capacity SOH for the battery according to the type of diagnostic factor. Hereinafter, it is explained that the values ​​of the positive participation start point (pi) and the positive participation end point (pf) represent the corresponding SOC in the adjusted positive profile, and the values ​​of the negative participation start point (ni) and the negative participation end point (nf) represent the corresponding SOC in the adjusted negative profile.

[0100] The positive SOH indicates the degree of degradation of the positive electrode of the battery. That is, the positive SOH is an indicator of the degree of degradation of the positive electrode of the battery. As the battery degrades, the positive reaction area decreases due to reasons such as the occurrence of side reactions, so the positive electrode capacity participating in the reaction may decrease. Therefore, the control unit (130) can estimate the degree of degradation regarding the loss of positive electrode capacity by calculating the positive SOH.

[0101] Specifically, when the control unit (130) extracts the anode participation endpoint (pf) as a diagnostic factor, it can calculate the anode SOH using the following formula 1 or formula 2.

[0102] [Formula 1]

[0103]

[0104] Here, SOH P is the anode SOH, and pf MOL is the value of the positive participation endpoint corresponding to the battery in its current state, and pf BOL is the value of the positive participation endpoint corresponding to the battery in the BOL state, and pi BOL is the value of the positive participation initiation point corresponding to the battery in the BOL state. Here, pf BOL , pi BOL and pf MOL can be the SOC value corresponding to the corresponding point.

[0105] [Equation 2]

[0106]

[0107] Here, nf BOL is the value of the negative participation endpoint corresponding to the battery in the BOL state, and ni BOL is the value of the negative electrode participation initiation point corresponding to the battery in the BOL state. Here, ni BOL and nf MOL can be the SOC value corresponding to the corresponding point.

[0108] For example, pi BOL and pf BOLIf set based on the anode capacity of this BOL state, ni BOL and nf BOL It can also be set based on the anode capacity in the BOL state. As another example, pi BOL and pf BOL If set based on the cathode capacity of this BOL state, ni BOL and nf BOL It can also be set based on the cathode capacitance in the BOL state. That is, pi BOL , pf BOL , ni BOL and nf BOL The reference capacity (anode or cathode capacity in the BOL state) serving as the basis for calculation may be the same. Therefore, referring to Equations 1 and 2, "pf BOL -pi BOL " is "nf BOL -ni BOL It can be replaced with "

[0109] In addition, when the control unit (130) extracts the anode change ratio (ps) as a diagnostic factor, it can calculate the anode SOH using the following formula 3.

[0110] [Equation 3]

[0111]

[0112] Here, ps BOL is the positive change ratio corresponding to the battery in the BOL state, and ps MOL is the positive change ratio corresponding to the battery in its current state. Specifically, ps BOL represents the ratio of change of the reference anode profile (Rp) to the initial anode profile. Here, if the initial anode profile and the reference anode profile (Rp) are the same, ps BOL can be 1 or 100%. For convenience of explanation, the initial anode profile and the reference anode profile (Rp) are described below as identical. And, ps MOLrepresents the ratio of change of the adjusted anode profile to the reference anode profile (Rp).

[0113] The negative electrode SOH indicates the degree of degradation of the negative electrode of the battery. That is, the negative electrode SOH is an indicator of the degree of degradation of the negative electrode of the battery. Similar to positive electrode capacity loss, as the battery degrades, the negative electrode reaction area decreases due to reasons such as the occurrence of side reactions, so the negative electrode capacity participating in the reaction may decrease. Therefore, the control unit (130) can estimate the degree of degradation regarding negative electrode capacity loss by calculating the negative electrode SOH.

[0114] Specifically, when the control unit (130) extracts the cathode change ratio (ns) as a diagnostic factor, it can calculate the cathode SOH using the following formula 4.

[0115] [Equation 4]

[0116]

[0117] Here, SOH N is the cathode SOH, and ns BOL is the negative electrode change ratio corresponding to the battery in the BOL state, and ns MOL is the negative electrode change ratio corresponding to the battery in its current state. Specifically, ns BOL represents the ratio of change of the reference cathode profile (Rn) to the initial cathode profile. Here, if the initial cathode profile and the reference cathode profile (Rn) are the same, pn BOL can be 1 or 100%. For convenience of explanation, the initial cathode profile and the reference cathode profile (Rn) are described below as being identical. And, ps MOL represents the ratio of change of the adjusted cathode profile to the reference cathode profile (Rn).

[0118] Available lithium SOH indicates the degradation of available lithium in the battery. That is, available lithium SOH is an indicator of the degradation of lithium ions participating in the reaction. When the lithium plating (Li-plating) phenomenon occurs, lithium metal may be deposited on the surface of the negative electrode. As the lithium plating phenomenon progresses, the amount of lithium metal deposited increases, so the number of lithium ions participating in the reaction may decrease. Therefore, the control unit (130) can estimate the degradation of the number of lithium ions participating in the reaction relative to the initial state by calculating the available lithium SOH.

[0119] Specifically, when the control unit (130) extracts the anode participation initiation point (pi) as a diagnostic factor, it can calculate the available lithium SOH using the following formula 5 or formula 6.

[0120] [Formula 5]

[0121]

[0122] [Equation 6]

[0123]

[0124] Here, SOH Li is soluble lithium SOH. pi MOL is the value of the positive participation initiation point corresponding to the battery in its current state. Here, pi MOL can be the SOC value corresponding to the corresponding point. And, referring to Equations 5 and 6 as with Equations 1 and 2, "pf BOL -pi BOL " is "nf BOL -ni BOL It can be replaced with "

[0125] Capacity SOH indicates the degree of capacity degradation of the battery. That is, Capacity SOH is an indicator representing the degree of degradation of the current available capacity relative to the initial capacity of the battery. As the battery degrades, the available capacity of the battery can naturally decrease. Therefore, the control unit (130) can estimate the degree of degradation of the current capacity relative to the initial capacity by calculating Capacity SOH.

[0126] Specifically, when the control unit (130) extracts the anode participation endpoint (pf) and the anode participation initiation point (pi) as diagnostic factors, it can calculate the capacity SOH using the following formula 7.

[0127] [Equation 7]

[0128]

[0129] Here, SOH Q is the capacity SOH. pf BOL , pi BOL , pf MOL and pi MOL is as explained earlier. And, "pf BOL -pi BOL " is "nf BOL -ni BOL It can be replaced with "

[0130] In addition, when the control unit (130) extracts the cathode participation end point (nf) and the cathode participation start point (ni) as diagnostic factors, it can calculate the capacity SOH using the following formula 8.

[0131] [Equation 8]

[0132]

[0133] Here, SOH Q is the capacity SOH, and nf MOL is the value of the negative participation endpoint corresponding to the battery in its current state, and ni MOL is the value of the negative electrode participation start point corresponding to the battery in its current state. That is, referring to Equations 7 and 8, "pf BOL -pi BOL" is "nf BOL -ni BOL It can be replaced with ", and "pf MOL -pi MOL " is "nf MOL -ni MOL It can be replaced with "

[0134] In the above, the control unit (130) is the positive SOH (SOH P ), cathode SOH(SOH N ), soluble lithium SOH (SOH Li ) and capacity SOH(SOH Q An example of estimating ) has been described. However, the control unit (130) may calculate the complement of 1 (or 100%) of SOH to estimate the anode degradation rate, cathode degradation rate, available lithium degradation rate, and capacity degradation rate. For example, the control unit (130) may estimate the anode degradation rate by calculating "1-anode SOH".

[0135] A SOH estimation device (100) according to one embodiment of the present invention can estimate the SOH of a battery in various aspects depending on the extracted diagnostic factors. For example, since the positive electrode SOH, negative electrode SOH, available lithium SOH, and capacity SOH can be estimated depending on the extracted diagnostic factors, the degree of degradation of the battery for each item can be specifically diagnosed.

[0137] The control unit (130) may be configured to adjust the usage conditions for the battery based on the estimated SOH.

[0138] Specifically, the control unit (130) can adjust the available SOC range for the battery based on the estimated SOH. For example, the control unit (130) can reduce the upper limit of the available SOC range for the battery. As another example, the control unit (130) can increase the lower limit of the available SOC range for the battery. As yet another example, the control unit (130) can reduce the upper limit of the available SOC range for the battery and increase the lower limit of the available SOC range.

[0139] By adjusting the available SOC range in this way, the loss of positive and negative reaction areas can be prevented. Furthermore, since the loss of available lithium is prevented, the precipitation of lithium metal can be prevented. In addition, the generation of gas inside the battery can be suppressed.

[0141] Hereinafter, with reference to FIGS. 7 to 14, an embodiment in which the profile correction unit (120) adjusts the reference anode profile (Rp) and the reference cathode profile (Rn) will be described in more detail.

[0142] FIGS. 7 to 14 are drawings illustrating the process of adjusting a reference anode profile (Rp) and a reference cathode profile (Rn) according to an embodiment of the present invention.

[0143] FIG. 7 is a graph referenced to illustrate an example of each of the reference anode profile (Rp) and the reference cathode profile (Rn). In the graph of FIG. 7, the horizontal axis (X-axis) represents capacity (Ah) and the vertical axis (Y-axis) represents voltage (V).

[0144] FIG. 8 is a graph referenced to illustrate an example of the OCV profile (Rocv) of a target battery. In the graph of FIG. 8, the horizontal axis (X-axis) represents capacity (capacity, Ah) and the vertical axis (Y-axis) represents voltage (voltage, V). Referring to FIG. 8, it is assumed that the target capacity range (T) is a capacity range of 5 (Ah) or more and 45 (Ah) or less.

[0145] The profile correction unit (120) may be configured to compare the OCV profile (Rocv) with at least one comparison full cell profile. Here, the comparison full cell profile may be the result of synthesizing (combining) an adjusted positive profile and an adjusted negative profile based on the reference positive profile (Rp) and the reference negative profile (Rn), respectively, stored in the storage unit (140).

[0146] That is, when the reference full cell profile (R) is the result of subtracting a portion of the reference cathode profile (Rn) from a portion of the reference anode profile (Rp), the comparison full cell profile can be said to be the result of subtracting a portion of the adjusted cathode profile from a portion of the adjusted anode profile.

[0147] The profile correction unit (120) can generate at least one comparison full cell profile by directly adjusting the reference anode profile (Rp) and the reference cathode profile (Rn). Alternatively, at least one comparison full cell profile may be obtained in advance based on the reference anode profile (Rp) and the reference cathode profile (Rn) and stored in the storage unit (140). In this case, the profile correction unit (120) may also obtain the comparison full cell profile by accessing the storage unit (140) and reading it.

[0148] The profile correction unit (120) can generate multiple comparison full cell profiles from the reference anode profile (Rp) and the reference cathode profile (Rn) by repeating an adjustment procedure in which the reference anode profile (Rp) and the reference cathode profile (Rn) are each adjusted to multiple levels and then synthesized. The comparison full cell profiles may also be referred to as 'adjusted reference full cell profiles'.

[0149] The profile correction unit (120) can identify one comparison full cell profile among a plurality of comparison full cell profiles that has the minimum error with the OCV profile (Rocv).

[0150] Next, the profile correction unit (120) can determine that the adjusted positive profile and the adjusted negative profile mapped to the specified comparison full cell profile are the positive profile and the negative profile of the battery. Note below that the positive profile is the finally determined adjusted positive profile and the negative profile is the finally determined adjusted positive profile.

[0151] In this regard, various methods known at the time of filing the present invention may be employed to determine the error between two profiles that can each be expressed in a two-dimensional coordinate system. For example, the integral of the absolute value of the area between the two profiles or the Root Mean Square Error (RMSE) may be used as the error between the two profiles.

[0152] According to this configuration of the present invention, various state information regarding the battery can be obtained based on the finally determined positive profile and negative profile. The finally determined positive profile and negative profile may be mapped to a comparative full cell profile mapped to a minimum error. In particular, the comparative full cell profile based on the finally determined positive profile and negative profile can be said to have a shape and shape that are almost identical to the OCV profile (Rocv).

[0153] Therefore, according to the present invention, the positive and negative profiles of the battery can be obtained without disassembling the battery.

[0154] In the case of a new battery, analyzing the positive and negative profiles of the battery can be more easily utilized to diagnose whether a defect has occurred in the battery, and if so, what type of defect it is.

[0155] In the case of a battery currently in use after being verified as a good quality product, the extent of battery degradation for each degradation category can be determined through the battery's positive and negative profiles.

[0156] Furthermore, according to one embodiment of the present invention, the positive and negative profiles of the battery can be obtained in a simple manner. The present invention can be implemented even if only one reference positive profile (Rp) and one reference negative profile (Rn) are stored in the storage unit (140). That is, there is no need to store multiple reference positive profiles (Rp) and / or multiple reference negative profiles (Rn) in the storage unit (140). Therefore, there is no need for the storage capacity of the storage unit (140) to be high, nor is there a need to conduct numerous preliminary tests required to obtain multiple reference positive profiles (Rp) and / or multiple reference negative profiles (Rn).

[0158] FIGS. 9 to 11 are drawings referenced to illustrate an example of a procedure for generating a comparison full-cell profile used for comparison with an OCV profile (Rocv) according to an embodiment of the present invention.

[0159] The procedure for generating a comparative full-cell profile to be described with reference to FIGS. 9 to 11 proceeds in the order of a first routine (see FIG. 9) for setting four points (anode participation start point, aode participation end point, cathode participation start point, cathode participation end point) corresponding to a voltage range of interest, a second routine (see FIG. 10) for performing a profile shift, and a third routine (see FIG. 11) for performing capacity scaling. That is, the procedure for generating a comparative full-cell profile according to one embodiment of the present invention includes the first to third routines.

[0160] First, referring to FIG. 9, the reference anode profile (Rp) and the reference cathode profile (Rn) are the same as those shown in FIG. 7.

[0161] The profile correction unit (120) determines the anode participation start point (pi), anode participation end point (pf), cathode participation start point (ni), and cathode participation end point (nf) on the reference anode profile (Rp) and the reference cathode profile (Rn).

[0162] Either the positive participation initiation point (pi) or the negative participation initiation point (ni) depends on the other.

[0163] For example, the profile correction unit (120) may divide the anode voltage range from the starting point to the ending point (or, a second set voltage) of the reference anode profile (Rp) into a plurality of microvoltage intervals, and then set the boundary point between two adjacent microvoltage intervals among the plurality of microvoltage intervals as the anode participation start point (pi). Each microvoltage interval may have a predetermined size (e.g., 0.01V). Then, the profile correction unit (120) may set a point on the reference cathode profile (Rn) that is smaller than the anode participation start point (pi) by a first set voltage (e.g., 3V) as the cathode participation start point (ni).

[0164] As another example, the profile correction unit (120) may divide the cathode voltage range from the starting point to the ending point of the reference cathode profile (Rn) into a plurality of microvoltage sections of a predetermined size, and then set the boundary point between two adjacent microvoltage sections among the plurality of microvoltage sections as the cathode participation start point (ni). Next, the profile correction unit (120) may search for a point from the reference anode profile (Rp) that is greater than the cathode participation start point (ni) by a first set voltage, and set the searched point as the anode participation start point (pi).

[0165] Either the positive participation endpoint (pf) or the negative participation endpoint (nf) depends on the other.

[0166] For example, the profile correction unit (120) may divide the voltage range from the second set voltage to the end point of the reference anode profile (Rp) into a plurality of small voltage intervals of a predetermined size, and then set the boundary point between two adjacent small voltage intervals among the plurality of small voltage intervals as the anode participation end point (pf). Then, the profile correction unit (120) may set a point on the reference cathode profile (Rn) that is smaller than the anode participation end point (pf) by the second set voltage (e.g., 4V) as the cathode participation end point (nf).

[0167] As another example, the profile correction unit (120) may divide the cathode voltage range from the starting point to the ending point of the reference cathode profile (Rn) into a plurality of minute voltage sections of a predetermined size, and then set the boundary point between two adjacent minute voltage sections among the plurality of minute voltage sections as the cathode participation ending point (nf). Next, the profile correction unit (120) may search for a point greater than the cathode participation ending point (nf) by a second set voltage from the reference anode profile (Rp), and set the searched point as the anode participation ending point (pf).

[0168] When the determination of the positive participation start point (pi), positive participation end point (pf), negative participation start point (ni), and negative participation end point (nf) is complete, the profile correction unit (120) shifts at least one of the reference positive profile (Rp) and the reference negative profile (Rn) to the left or right along the horizontal axis.

[0169] Referring to FIG. 10, the profile correction unit (120) can shift the reference anode profile (Rp) and / or reference cathode profile (Rn) so that the capacitance values ​​of the anode participation start point (pi) and the cathode participation start point (ni) match.

[0170] Alternatively, the profile correction unit (120) can shift the reference anode profile (Rp) and / or reference cathode profile (Rn) so that the voltages of the anode participation endpoint (pf) and the cathode participation endpoint (nf) match.

[0171] FIG. 10 illustrates a situation where only the reference anode profile (Rp) is shifted to the left to generate an adjusted reference anode profile (Rp'), and as a result, the voltage at the anode participation initiation point (pi') matches the voltage at the cathode participation initiation point (ni). The adjusted reference anode profile (Rp') is the result of applying an adjustment procedure to the reference anode profile (Rp) that shifts it to the left by the voltage difference between the anode participation initiation point (pi) and the cathode participation initiation point (ni). Therefore, the two points (pi, pi') differ only in their capacitance values ​​and have the same voltage. The two points (pf, pf') differ only in their capacitance values ​​and have the same voltage.

[0172] When adjustment result profiles (Rp', Rn) are obtained in which at least one of the reference anode profile (Rp) and the reference cathode profile (Rn) is shifted, the profile correction unit (120) scales the capacity range of at least one of the adjustment result profiles (Rp', Rn).

[0173] According to the example illustrated in FIG. 10, the profile correction unit (120) performs an additional adjustment procedure to contract or expand at least one of the adjusted reference anode profile (Rp') and reference cathode profile (Rn) along the horizontal axis.

[0174] Referring to FIG. 11, the profile correction unit (120) can generate an adjusted reference anode profile (Rp'') by shrinking or expanding the adjusted reference anode profile (Rp') so that the size of the capacity range between two points (pi', pf') of the adjusted reference anode profile (Rp') matches the size of the target capacity range (T) of the OCV profile (Rocv). At this time, either of the two points (pi', pf') may be fixed. Accordingly, the capacity difference between two points (pi', pf'') of the adjusted reference anode profile (Rp'') may match the target capacity range (T) of the OCV profile (Rocv).

[0175] Additionally, the profile correction unit (120) can generate an adjusted reference cathode profile (Rn') by shrinking or expanding the reference cathode profile (Rn) so that the size of the capacity range between two points (ni, nf) of the reference cathode profile (Rn) also matches the size of the target capacity range (T) of the OCV profile (Rocv). At this time, either of the two points (ni, nf) may be fixed. Accordingly, the capacity difference between two points (ni, nf') of the adjusted reference cathode profile (Rn') may match the target capacity range (T) of the OCV profile (Rocv).

[0176] In FIG. 11, the adjusted reference anode profile (Rp'') is the result of the adjusted reference anode profile (Rp') shown in FIG. 8 being contracted, and the adjusted reference cathode profile (Rn') is the result of the reference cathode profile (Rn) shown in FIG. 10 being expanded.

[0177] The anode participation endpoint (pf'') on the adjusted reference anode profile (Rp'') corresponds to the anode participation endpoint (pf) on the adjusted reference anode profile (Rp'). The cathode participation endpoint (nf') on the adjusted reference cathode profile (Rn') corresponds to the cathode participation endpoint (nf) on the reference cathode profile (Rn).

[0178] The capacity difference between the anode participation start point (pi') and the anode participation end point (pf'') of the adjusted reference anode profile (Rp'') corresponds to the size of the target capacity range (T) of the OCV profile (Rocv). Likewise, the capacity difference between the cathode participation start point (ni) and the cathode participation end point (nf') of the adjusted reference cathode profile (Rn') corresponds to the size of the target capacity range (T) of the OCV profile (Rocv).

[0179] Additionally, the capacity range by two points (pi', pf'') of the adjusted reference anode profile (Rp'') corresponds to the capacity range by two points (ni, nf') of the adjusted reference cathode profile (Rn'). The profile correction unit (120) can generate a comparison full cell profile (S) by subtracting the profile between two points (pi, pf') of the adjusted reference anode profile (Rp'') from the profile between two points (ni, nf') of the adjusted reference cathode profile (Rn').

[0180] The profile correction unit (120) can calculate the error (profile error) between the comparison full cell profile (S) and the OCV profile (Rocv). When the error between the comparison full cell profile (S) and the OCV profile (Rocv) is minimized, the adjusted reference anode profile (Rp'') corresponding to the comparison full cell profile (S) can be determined as the adjusted anode profile, and the adjusted reference cathode profile (Rn') can be determined as the adjusted cathode profile.

[0181] The profile correction unit (120) can mutually map at least two of the adjusted reference anode profile (Rp''), adjusted reference cathode profile (Rn'), anode participation start point (pi'), anode participation end point (pf''), cathode participation start point (ni), cathode participation end point (nf'), first scale factor, second scale factor, comparison full cell profile (S), and profile error, and record them in the storage unit (140). The first scale factor may represent the ratio of the capacity difference between two points (pi', pf'') to the capacity difference between two points (pi0, pf0). The second scale factor may represent the ratio of the capacity difference between two points (ni, nf') to the capacity difference between two points (ni0, nf0).

[0182] Here, the profile correction unit (120) can calculate the anode change ratio (ps) of the adjusted reference anode profile (Rp'') with respect to the reference anode profile (Rp). And, the profile correction unit (120) can calculate the cathode change ratio (ns) of the adjusted reference anode profile (Rn') with respect to the reference cathode profile (Rn). For example, the profile correction unit (120) can determine a first scale factor as the anode change ratio (ps) and a second scale factor as the cathode change ratio (ns).

[0184] Meanwhile, as described above, when the anode voltage range of the reference anode profile (Rp) is divided into multiple microvoltage intervals, the boundary point between two adjacent microvoltage intervals among the multiple microvoltage intervals can be set as the anode participation start point (pi).

[0185] For example, if the anode voltage range of the reference anode profile (Rp) is divided into 100 microvoltage ranges, there may be 100 boundary points that can be set as anode participation start points (pi). Additionally, if the voltage range of the reference anode profile (Rp) that is greater than or equal to the second set voltage is divided into 40 microvoltage ranges, there may be 40 boundary points that can be set as anode participation end points (pf). In this case, up to 4,000 different comparison full cell profiles can be generated.

[0186] Of course, those skilled in the art will easily understand that as the size of the microvoltage interval decreases, the maximum number of comparable full-cell profiles that can be generated increases, and conversely, as the size of the microvoltage interval increases, the maximum number of comparable full-cell profiles that can be generated decreases.

[0187] The profile correction unit (120) can identify the minimum value among the profile errors of a plurality of comparison full cell profiles generated as described above, and then obtain information mapped to the minimum profile error (e.g., at least one of the anode participation start point (pi), anode participation end point (pf), cathode participation start point (ni), cathode participation end point (nf), anode change ratio (ps), cathode change ratio (ns)) from the storage unit (140).

[0189] FIGS. 12 to 14 are reference drawings for illustrating another example of a procedure for generating a comparison full-cell profile used for comparison with an OCV profile (Rocv) according to one embodiment of the present invention. For reference, the embodiment according to FIGS. 12 to 14 is independent of the embodiment according to FIGS. 9 to 11. Accordingly, terms or symbols commonly used to describe the embodiment according to FIGS. 9 to 11 and the embodiment according to FIGS. 12 to 14 should be understood as being limited to each respective embodiment.

[0190] The procedure for generating a comparative full-cell profile to be described with reference to FIGS. 12 to 14 proceeds in the order of a fourth routine for performing capacity scaling (see FIG. 12), a fifth routine for setting four points (anode participation start point, aode participation end point, cathode participation start point, cathode participation end point), and a sixth routine for performing profile shifting (see FIG. 14). That is, the procedure for generating a comparative full-cell profile according to another embodiment of the present invention includes the fourth to sixth routines.

[0191] Referring to FIG. 12, the reference anode profile (Rp) and the reference cathode profile (Rn) are the same as those shown in FIG. 7.

[0192] The profile correction unit (120) applies a first scale factor and a second scale factor selected from a scaling numerical range to a reference anode profile (Rp) and a reference cathode profile (Rn), respectively, to generate an adjusted reference anode profile (Rp') and an adjusted reference cathode profile (Rn').

[0193] The scaling numerical range may be predetermined or vary according to the ratio of the size of the target capacity range (T) of the OCV profile (Rocv) to the size of the capacity range of the reference full cell profile (R). For example, when values ​​spaced at intervals of 0.1% of the scaling numerical range (e.g., 90–99%) (i.e., 90%, 90.1%, 90.2%, … 98.9%, 99%) can be selected as the first scale factor and the second scale factor, 91 values ​​can be selected as the first scale factor and the second scale factor, respectively. In this case, up to 8,281 adjusted profile pairs can be generated according to 91 × 91 = 8,281 adjustment levels (combinations of the first scale factor and the second scale factor). An adjusted profile pair refers to a combination of an adjusted reference anode profile and an adjusted reference cathode profile.

[0194] The adjusted reference anode profile (Rp') and adjusted reference cathode profile (Rn') shown in FIG. 12 illustrate the results of applying a first scale factor and a second scale factor of less than 100% to the reference anode profile (Rp) and reference cathode profile (Rn), respectively.

[0195] Since the first scale factor and the second scale factor are less than 100%, the adjusted reference anode profile (Rp') is the reference anode profile (Rp) contracted along the horizontal axis, and the adjusted reference cathode profile (Rn') is also the reference cathode profile (Rn) contracted along the horizontal axis. For better understanding, the starting points of the anode profile (Rp) and the reference cathode profile (Rn) are fixed, and the remaining parts are contracted to the left along the horizontal axis as an example.

[0197] Referring to FIG. 13, the profile correction unit (120) determines an anode participation start point (pi'), an anode participation end point (pf'), a cathode participation start point (ni'), and a cathode participation end point (nf') on an adjusted reference anode profile (Rp') and an adjusted reference cathode profile (Rn').

[0198] Either the anode participation initiation point (pi') or the cathode participation initiation point (ni') may depend on the other. Additionally, either the anode participation endpoint (pf') or the cathode participation endpoint (nf') may depend on the other. Furthermore, either the anode participation initiation point (pi') or the anode participation endpoint (pf') may be established based on the other.

[0199] That is, when any one of the positive participation start point (pi'), positive participation end point (pf'), negative participation start point (ni') and negative participation end point (nf') is set, the remaining three points can be automatically set by the first set voltage, the second set voltage and / or the size of the target capacity range (T) of the OCV profile (Rocv) (e.g., charging capacity of 0 to 100% capacity value).

[0200] For example, the profile correction unit (120) may divide the anode voltage range from the starting point to the ending point (or, a second set voltage) of the adjusted reference anode profile (Rp') into a plurality of microvoltage intervals, and then set the boundary point between two adjacent microvoltage intervals among the plurality of microvoltage intervals as the anode participation start point (pi'). Then, the profile correction unit (120) may set a point on the adjusted reference cathode profile (Rn) that is smaller than the anode participation start point (pi') by a first set voltage (e.g., 3V) as the cathode participation start point (ni').

[0201] As another example, the profile correction unit (120) may divide the cathode voltage range from the start point to the end point of the adjusted reference cathode profile (Rn') into a plurality of microvoltage sections of a predetermined size, and then set the boundary point between two adjacent microvoltage sections among the plurality of microvoltage sections as the cathode participation start point (ni'). Next, the profile correction unit (120) may search for a point greater than the cathode participation start point (ni') by a first set voltage from the reference anode profile (Rp), and set the searched point as the anode participation start point (pi').

[0202] As another example, the profile correction unit (120) may divide the voltage range from the second set voltage to the end point of the adjusted reference anode profile (Rp') into a plurality of small voltage segments of a predetermined size, and then set the boundary point between two adjacent small voltage segments among the plurality of small voltage segments as the anode participation end point (pf'). Then, the profile correction unit (120) may search for a point in the adjusted reference cathode profile (Rn') that is smaller than the anode participation end point (pf') by the second set voltage (e.g., 4V), and set the searched point as the cathode participation end point (nf').

[0203] As another example, the profile correction unit (120) may divide the cathode voltage range from the start point to the end point of the adjusted reference cathode profile (Rn') into a plurality of microvoltage sections of a predetermined size, and then set the boundary point between two adjacent microvoltage sections among the plurality of microvoltage sections as the cathode participation end point (nf'). Next, the profile correction unit (120) may search for a point greater than the cathode participation end point (nf') by a second set voltage from the adjusted reference anode profile (Rp'), and set the searched point as the anode participation end point (pf').

[0205] The profile correction unit (120) can additionally determine the remaining three points based on the determined point when any one of the anode participation start point (pi'), anode participation end point (pf'), cathode participation start point (ni') and cathode participation end point (nf') is determined.

[0206] For example, if the anode participation start point (pi') is determined first, the profile correction unit (120) can set a point on the adjusted reference anode profile (Rp') having a capacity value larger than the capacity value of the anode participation start point (pi') by the size of the target capacity range (T) of the OCV profile (Rocv) as the anode participation end point (pf'). Additionally, the profile correction unit (120) can search for a point lower than the anode participation start point (pi') by the first set voltage from the adjusted reference cathode profile (Rn') and set the searched point as the cathode participation start point (ni'). Additionally, the profile correction unit (120) can set a point on the adjusted reference cathode profile (Rn') having a capacity value larger than the capacity value of the cathode participation start point (ni') by the size of the target capacity range (T) of the OCV profile (Rocv) as the cathode participation end point (nf').

[0207] As another example, the profile correction unit (120) can set a point on the adjusted reference anode profile (Rp') having a capacity value smaller than the capacity value of the anode participation endpoint (pf') by the size of the target capacity range (T) of the OCV profile (Rocv) as the anode participation start point (pi') when the anode participation endpoint (pf') is determined first. Additionally, the profile correction unit (120) can search for a point lower than the anode participation endpoint (pf') by the second set voltage from the adjusted reference cathode profile (Rn') and set the searched point as the cathode participation endpoint (nf'). Additionally, the profile correction unit (120) can set a point on the adjusted reference cathode profile (Rn') having a capacity value smaller than the capacity value of the cathode participation endpoint (nf') by the size of the target capacity range (T) of the OCV profile (Rocv) as the cathode participation start point (ni').

[0208] As another example, when the cathode participation start point (ni') is determined, the profile correction unit (120) can set a point on the adjusted reference cathode profile (Rn') having a capacitance value larger than the capacitance value of the cathode participation start point (ni') by the size of the target capacitance range (T) of the OCV profile (Rocv) as the cathode participation end point (nf'). Additionally, the profile correction unit (120) can search for a point higher than the cathode participation start point (ni') by the first set voltage from the adjusted reference anode profile (Rp') and set the searched point as the anode participation start point (pi'). Additionally, the profile correction unit (120) can set a point on the adjusted reference anode profile (Rp') having a capacitance value larger than the capacitance value of the anode participation start point (pi') by the size of the target capacitance range (T) of the OCV profile (Rocv) as the anode participation end point (pf').

[0209] As another example, when the cathode participation endpoint (nf') is determined, the profile correction unit (120) can set a point on the adjusted reference cathode profile (Rn') having a capacitance value smaller than the capacitance value of the cathode participation endpoint (nf') by the size of the target capacitance range (T) of the OCV profile (Rocv) as the cathode participation start point (ni'). Additionally, the profile correction unit (120) can search for a point higher than the cathode participation endpoint (nf') by the second set voltage from the adjusted reference anode profile (Rp') and set the searched point as the anode participation endpoint (pf'). Additionally, the profile correction unit (120) can set a point on the adjusted reference anode profile (Rp') having a capacitance value smaller than the capacitance value of the anode participation endpoint (pf') by the size of the target capacitance range (T) of the OCV profile (Rocv) as the anode participation start point (pi').

[0211] When the determination of the anode participation start point (pi'), anode participation end point (pf'), cathode participation start point (ni'), and cathode participation end point (nf') is completed based on the pair of the first scale factor and the second scale factor, the profile correction unit (120) can shift at least one of the adjusted reference anode profile (Rp') and the adjusted reference cathode profile (Rn') along the horizontal axis so that the capacitance values ​​of the anode participation start point (pi') and the cathode participation start point (ni') match, or the capacitance values ​​of the anode participation end point (pf') and the cathode participation end point (nf') match.

[0212] The adjusted reference cathode profile (Rn'') shown in FIG. 14 is the adjusted reference cathode profile (Rn') shown in FIG. 13 shifted only to the right. Accordingly, the capacitance values ​​of the anode participation start point (pi') and the cathode participation start point (ni'') match each other. In this regard, since the capacitance difference between the anode participation start point (pi') and the anode participation end point (pf') is the same as the capacitance difference between the cathode participation start point (ni') and the cathode participation end point (nf'), when the capacitance values ​​of the anode participation start point (pi') and the cathode participation start point (ni'') match each other, the capacitance values ​​of the anode participation end point (pf') and the cathode participation end point (nf'') also match each other.

[0213] Referring to FIG. 14, the profile correction unit (120) can generate a comparison full cell profile (U) by subtracting the partial profile between two points (pi', pf') of the adjusted reference anode profile (Rp') from the partial profile between two points (ni'', nf'') of the adjusted reference cathode profile (Rn'').

[0214] The profile correction unit (120) can calculate the error (profile error) between the comparison full cell profile (U) and the OCV profile (Rocv). When the error between the comparison full cell profile (U) and the OCV profile (Rocv) is minimized, the adjusted reference anode profile (Rp') corresponding to the comparison full cell profile (U) can be determined as the adjusted anode profile, and the adjusted reference cathode profile (Rn'') can be determined as the adjusted cathode profile.

[0215] The profile correction unit (120) can mutually map at least two of the adjusted reference anode profile (Rp'), adjusted reference cathode profile (Rn''), anode participation start point (pi'), anode participation end point (pf'), cathode participation start point (ni''), cathode participation end point (nf''), anode change rate (ps), cathode change rate (ns), comparison full cell profile (U), and profile error and record them in the storage unit (140).

[0216] Here, the profile correction unit (120) can calculate the anode change ratio (ps) of the adjusted reference anode profile (Rp') with respect to the reference anode profile (Rp). And, the profile correction unit (120) can calculate the cathode change ratio (ns) of the adjusted reference anode profile (Rn'') with respect to the reference cathode profile (Rn). For example, the profile correction unit (120) can determine a first scale factor as the anode change ratio (ps) and a second scale factor as the cathode change ratio (ns).

[0217] As described above, the profile correction unit (120) can generate a corresponding comparison full cell profile for each pair of a first scale factor and a second scale factor selected from a scaling numerical range. Since there are multiple pairs of the first scale factor and the second scale factor, it is obvious that multiple comparison full cell profiles will also be generated. The profile correction unit (120) can identify the minimum value among the profile errors of the multiple comparison full cell profiles and then obtain information mapped to the minimum profile error from the storage unit (140).

[0219] The SOH estimation device (100) according to the present invention is connected to a display device (not shown) and can output information regarding the SOH of a battery. As a result, information regarding the SOH of a battery can be displayed on the display device.

[0220] The SOH estimation device (100) according to the present invention is connected to an alarm device (not shown) and can operate the alarm device by outputting information regarding the SOH of the battery.

[0221] The SOH estimation device (100) according to the present invention may be applied to a Battery Management System (BMS). That is, the BMS according to the present invention may include the SOH estimation device (100) described above. In this configuration, at least some of the components of the SOH estimation device (100) may be implemented by supplementing or adding the functions of the components included in a conventional BMS. For example, the profile acquisition unit (110), profile correction unit (120), control unit (130), and storage unit (140) of the SOH estimation device (100) may be implemented as components of the BMS. In addition, the SOH estimation device (100) according to the present invention may be provided in a battery pack. That is, the battery pack according to the present invention may include the SOH estimation device (100) described above and one or more battery cells. In addition, the battery pack may further include electrical components (relays, fuses, etc.) and a case, etc.

[0222] FIG. 15 is a drawing illustrating an exemplary configuration of a battery pack (1) according to another embodiment of the present invention.

[0223] The positive terminal of the battery (10) can be connected to the positive terminal (P+) of the battery pack (1), and the negative terminal of the battery (10) can be connected to the negative terminal (P-) of the battery pack (1).

[0224] The measuring unit (20) can be connected to the positive terminal and the negative terminal of the battery (10). The measuring unit (20) can measure the positive potential and the negative potential of the battery (10), and calculate the difference between the positive potential and the negative potential to measure the voltage of the battery (10). Preferably, the measuring unit (20) can measure the OCV of the battery (10).

[0225] Additionally, the measuring unit (20) may be connected to a current measuring unit (A). For example, the current measuring unit (A) may be an ammeter or a shunt resistor capable of measuring the charging current and discharging current of the battery (10). The measuring unit (20) may use the current measuring unit (A) to measure the charging current of the battery (10) and calculate the amount of charge. Furthermore, the measuring unit (20) may measure the discharging current of the battery (10) through the third sensing line (SL3) and calculate the amount of discharge.

[0226] For example, information regarding the voltage and capacity of the battery (10) measured by the measuring unit (20) can be transmitted to the profile acquisition unit (110). Then, the profile acquisition unit (110) can directly generate an OCV profile (Rocv) based on the received information regarding the voltage and capacity.

[0227] As another example, information regarding the voltage and capacity of the battery (10) measured by the measuring unit (20) can be stored in the storage unit (140). When the charging or discharging of the battery (10) is finished, the profile acquisition unit (110) can access the storage unit (140) to acquire the OCV profile (Rocv).

[0228] As another example, the measuring unit (20) may directly generate an OCV profile (Rocv) based on information regarding the voltage and capacity of the measured battery (10). In this case, the generated OCV profile (Rocv) is transmitted to the profile acquisition unit (110) and may also be stored in the storage unit (140).

[0229] A charging / discharging device or a load can be connected to the positive terminal (P+) and negative terminal (P-) of the battery pack (1).

[0231] FIG. 16 is a drawing illustrating an exemplary configuration of a vehicle according to another embodiment of the present invention.

[0232] Referring to FIG. 16, a battery pack (1610) according to an embodiment of the present invention may be included in a vehicle (1600), such as an electric vehicle (EV) or a hybrid vehicle (HV). The battery pack (1610) can drive the vehicle (1600) by supplying power to a motor through an inverter provided in the vehicle (1600). Here, the battery pack (1610) may include a SOH estimation device (100). That is, the vehicle (1600) may include a SOH estimation device (100).

[0233] In this case, the SOH estimation device (100) may be an on-board diagnostic device included in the vehicle (1600). That is, the SOH estimation device (100) can estimate the SOH of the battery in various aspects based on the OCV profile for the battery included in the vehicle (1600). And, the SOH estimation device (100) can provide information regarding the estimated SOH to the user.

[0235] FIG. 17 is a schematic diagram illustrating a method for estimating SOH according to another embodiment of the present invention.

[0236] Referring to FIG. 17, the SOH estimation method may include a profile acquisition step (S100), a profile adjustment step (S200), a diagnostic factor extraction step (S300), and an SOH estimation step (S400).

[0237] Preferably, each step of the SOH estimation method can be performed by the SOH estimation device (100). For convenience of explanation, details that overlap with previously described content will be omitted or briefly explained below.

[0238] The profile acquisition step (S100) is a step of acquiring OCV profiles (Rocv) for multiple OCVs of a battery measured at different points in time, and can be performed by a profile acquisition unit (110).

[0239] For example, the profile acquisition unit (110) can directly receive an OCV profile (Rocv) from the outside. That is, the profile acquisition unit (110) can acquire an OCV profile (Rocv) by receiving an OCV profile (Rocv) through a wired and / or wireless connection to the outside.

[0240] As another example, the profile acquisition unit (110) can receive battery information regarding the OCV and capacity values ​​of the battery. Then, the profile acquisition unit (110) can generate an OCV profile (Rocv) based on the received battery information. That is, the profile acquisition unit (110) can acquire an OCV profile (Rocv) by directly generating an OCV profile (Rocv) based on the battery information.

[0241] The profile adjustment step (S200) is a step of adjusting a preset reference anode profile and a reference cathode profile to correspond to an OCV profile (Rocv) to generate an adjusted anode profile and an adjusted cathode profile, and can be performed by a profile correction unit (120).

[0242] For example, the profile correction unit (120) can generate a plurality of comparison full cell profiles by shifting or capacity scaling the reference anode profile and the reference cathode profile, and can identify a comparison full cell profile among the plurality of comparison full cell profiles that minimizes the error with the OCV profile (Rocv). Then, an adjustment anode profile and an adjustment cathode profile corresponding to the identified comparison full cell profile can be determined.

[0243] The diagnostic factor extraction step (S300) is a step of extracting diagnostic factors regarding the negative participation start point and negative participation end point for the battery in the adjusted negative electrode profile, and can be performed by the control unit (130).

[0244] The SOH estimation step (S400) is a step of estimating the capacity SOH of a battery based on extracted diagnostic factors, and can be performed by the control unit (130).

[0245] Referring to Equation 4, the control unit (130) can estimate the capacity SOH (SOH_Q) based on the value of the cathode participation start point (ni), the reference value (R_ni), the value of the cathode participation end point (nf), and the reference value (R_nf).

[0247] The embodiments of the present invention described above are not limited to implementation through devices and methods, but may also be implemented through a program that realizes a function corresponding to the configuration of the embodiments of the present invention or a recording medium on which such a program is recorded. Such implementation can be easily achieved by a person skilled in the art to which the present invention pertains, based on the description of the embodiments described above.

[0248] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0249] Furthermore, since the present invention described above allows for various substitutions, modifications, and changes within the scope of the technical concept of the present invention to those skilled in the art without departing from the technical spirit of the present invention, it is not limited by the aforementioned embodiments and attached drawings, but rather all or part of each embodiment may be selectively combined to allow for various modifications. Explanation of the symbols

[0251] 1: Battery pack 10: Battery 20: Measurement section 100: SOH Estimation Device 110: Profile Acquisition Section 120: Profile Correction Section 130: Control unit 140: Storage section 1600: Cars 1610: Battery Pack

Claims

Claim 1 A profile acquisition unit configured to acquire an OCV profile representing a correspondence relationship between multiple OCVs (Open circuit voltages) and capacities of a battery measured at different points in time; and a profile correction unit configured to generate an adjusted positive profile and an adjusted negative profile by adjusting a preset reference positive profile and a reference negative profile to correspond to the OCV profile. An SOH estimation device comprising a control unit configured to extract diagnostic factors for the battery from the adjusted positive electrode profile or the adjusted negative electrode profile and to estimate the capacity SOH (State of Health) of the battery based on the extracted diagnostic factors, wherein the reference positive electrode profile is configured to represent a correspondence relationship between the capacity and OCV of a reference positive electrode cell configured to correspond to the positive electrode of the battery, and the reference negative electrode profile is configured to represent a correspondence relationship between the capacity and OCV of a reference negative electrode cell configured to correspond to the negative electrode of the battery, and wherein the plurality of OCVs are configured to include at least one of the OCV measured at the time when the battery transitions from a resting state to a discharge state and the OCV measured while the state in which the discharge current of the battery is below a preset threshold current is maintained for a preset reference time or longer. Claim 2 delete Claim 3 An SOH estimation device according to claim 1, characterized in that the plurality of OCVs are configured to include a plurality of OCVs measured within a preset reference period. Claim 4 An SOH estimation device according to claim 3, wherein the reference period is set as a preset target period, a period required to measure a preset number of OCVs, a period required for the SOH of the battery to decrease by a preset reference SOH, or a combination thereof. Claim 5 An SOH estimation device according to claim 1, wherein the profile correction unit is configured to generate a comparison full cell profile based on the reference anode profile and the reference cathode profile, and to generate the adjustment anode profile and the adjustment cathode profile by adjusting the reference anode profile and the reference cathode profile until the generated comparison full cell profile corresponds to the OCV profile. Claim 6 An SOH estimation device according to claim 5, wherein the profile correction unit is configured to determine a target capacity range corresponding to the OCV profile and to compare the comparison full cell profile and the OCV profile within the target capacity range. Claim 7 An SOH estimation device according to claim 1, wherein the control unit is configured to estimate the dose SOH by comparing a preset reference value for the diagnostic factor with the value of the diagnostic factor. Claim 8 An SOH estimation device according to claim 1, wherein the control unit is configured to adjust usage conditions for the battery based on the estimated capacity SOH. Claim 9 A battery pack comprising a SOH estimation device according to any one of paragraphs 1 and 3 through 8. Claim 10 An automobile comprising an SOH estimation device according to any one of paragraphs 1 and 3 through 8. Claim 11 A server comprising an SOH estimation device according to any one of paragraphs 1 and 3 through 8. Claim 12 A profile acquisition step in which, in a profile acquisition unit, an OCV profile is acquired that represents a correspondence relationship between a plurality of OCVs (Open circuit voltages) and capacities of a battery measured at different points in time; a profile adjustment step in which, in a profile correction unit, a preset reference positive profile and a reference negative profile are adjusted to correspond to the OCV profile to generate an adjusted positive profile and an adjusted negative profile; and a diagnostic factor extraction step in which, in a control unit, a diagnostic factor for the battery is extracted from the adjusted positive profile or the adjusted negative profile. A method for estimating SOH, comprising, in the control unit, a step of estimating the capacity SOH (State of health) of the battery based on extracted diagnostic factors, wherein the reference positive electrode profile is pre-set to represent a correspondence relationship between the capacity and OCV of a reference positive electrode cell pre-set to correspond to the positive electrode of the battery, the reference negative electrode profile is pre-set to represent a correspondence relationship between the capacity and OCV of a reference negative electrode cell pre-set to correspond to the negative electrode of the battery, and wherein the plurality of OCVs are configured to include at least one of the OCV measured at the time when the battery transitions from a resting state to a discharge state and the OCV measured while the state in which the discharge current of the battery is below a pre-set threshold current is maintained for a pre-set reference time or longer.

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