Battery management device and method

Abstract

A battery management apparatus according to the present disclosure includes: a split line obtaining unit configured to obtain a first split line of each of a plurality of batteries included in a battery pack; and a diagnosis unit configured to calculate a target value of each of the plurality of batteries based on a first target point or a target ratio of each of the plurality of first sectional lines, generate a distribution sectional line representing a correspondence relationship between the calculated plurality of target values and a numerical value of each of the plurality of target values, determining whether the distribution section line satisfies a predetermined condition, and diagnosing a state of the battery pack based on a result of the determination.

Description

Technical Field

[0001] This disclosure relates to battery management apparatus and methods, and more specifically to battery management apparatus and methods capable of diagnosing the state of a battery pack.

[0002] This application is based on and claims priority to Korean Patent Applications Nos. 10-2024-0005648, 10-2024-0005656, 10-2024-0005647, 10-2024-0005634, 10-2024-0005640 and 10-2024-0005657, filed on January 12, 2024, the disclosures of which are incorporated herein by reference in their entirety. Background Technology

[0003] Recently, demand for portable electronic products such as laptops, cameras, and mobile phones has increased dramatically, and electric vehicles, energy storage batteries, robots, and satellites have seen significant development. Therefore, high-performance batteries that allow for repeated charging and discharging are being actively researched.

[0004] Currently available batteries include nickel-cadmium (NiCd), nickel-metal hydride (NiMH), nickel-zinc (NiZn), and lithium-ion batteries. Among them, lithium-ion batteries have attracted much attention because they have almost no memory effect compared to nickel-based batteries, and also have a very low self-discharge rate and high energy density.

[0005] Batteries are used in a variety of fields, and in areas where batteries are increasingly used, such as electric vehicles or smart grid systems, large-capacity batteries are often required. To increase the capacity of a battery pack, there are methods to increase the capacity of the secondary batteries (i.e., the individual battery cells themselves). However, in this case, while the increase in capacity is not significant, there are physical limitations to expanding the size of the secondary batteries, and management is inconvenient. Therefore, battery packs in which multiple battery cells are connected in series and parallel are commonly used. Summary of the Invention

[0006] Technical issues

[0007] This disclosure is designed to address the problems of the related technologies, and therefore aims to provide a battery management device and method capable of diagnosing the deterioration and imbalance state among multiple batteries included in a battery pack.

[0008] These and other objects and advantages of this disclosure will become apparent from the following detailed description and will become even more fully apparent from exemplary embodiments of this disclosure. Moreover, it will be readily understood that the objects and advantages of this disclosure can be achieved by the means set forth in the appended claims and combinations thereof.

[0009] Technical solution

[0010] A battery management apparatus according to one aspect of the present disclosure includes: a profile obtaining unit configured to obtain a first profile of each of a plurality of batteries included in a battery pack; and a diagnostic unit configured to calculate a target value for each of the plurality of batteries based on a first target point or target ratio of each of the plurality of first profiles, generate a distribution profile representing the correspondence between the calculated plurality of target values ​​and the numerical values ​​of each of the plurality of target values, determine whether the distribution profile meets predetermined conditions, and diagnose the state of the battery pack based on the determination result.

[0011] The first cross-section can be either the positive electrode cross-section or the negative electrode cross-section.

[0012] The first target point can be either the starting point indicating the start of the charging reaction or the end of the discharging reaction in the first profile, or the ending point indicating the end of the charging reaction or the start of the discharging reaction in the first profile.

[0013] The target ratio can be the rate of change between the first profile and a preset reference profile.

[0014] The diagnostic unit can be configured to diagnose the battery pack as a degraded and unbalanced state when the distribution profile does not meet predetermined conditions.

[0015] The diagnostic unit can be configured to compare the feature values ​​of the distribution profile with a preset threshold when the distribution profile meets predetermined conditions.

[0016] The diagnostic unit can be configured to diagnose the state of the battery pack based on the comparison results.

[0017] The diagnostic unit can be configured to diagnose the battery pack as a degraded and unbalanced state when the characteristic value exceeds a threshold.

[0018] The diagnostic unit can be configured to diagnose the battery pack as a degraded equilibrium state when the feature value is less than or equal to a threshold.

[0019] The diagnostic unit can be configured to set thresholds based on the battery pack's degradation level and preset reference characteristic values.

[0020] The diagnostic unit can be configured to calculate a first value and a second value based on multiple target values.

[0021] The diagnostic unit can be configured to determine whether the distribution profile meets predetermined conditions based on the ratio between the first value and the second value.

[0022] The diagnostic unit can be configured to determine the minimum, maximum, and reference values ​​from multiple target values.

[0023] The diagnostic unit can be configured to calculate the difference between the minimum value and the reference value as the first value.

[0024] The diagnostic unit can be configured to calculate the difference between a reference value and a maximum value as a second value.

[0025] The diagnostic unit can be configured to determine the target value with the largest corresponding value among multiple target values ​​as the reference value.

[0026] The diagnostic unit can be configured to determine that the distribution profile meets a predetermined condition when the ratio falls within a preset threshold ratio range.

[0027] The diagnostic unit can be configured to determine that the distribution profile does not meet a predetermined condition when the ratio does not belong to a threshold ratio range.

[0028] The diagnostic unit can be configured to calculate the SOC of the first target point based on the ratio of the capacity value of the first target point to a reference capacity set for each of the multiple batteries.

[0029] The diagnostic unit can be configured to determine the calculated SOC as the target value.

[0030] The diagnostic unit can be configured to determine the target ratio as a target value.

[0031] The diagnostic unit can be configured to determine a target value based on the ratio between a preset reference ratio and a target ratio for each of the multiple batteries.

[0032] The diagnostic unit can be configured to operate functions to resolve the imbalance or output an alarm when the battery pack is diagnosed as being in a degraded or unbalanced state.

[0033] The function used to resolve deterioration and imbalance can be the group balancing function.

[0034] According to another aspect of this disclosure, a battery pack includes a battery management device according to one aspect of this disclosure.

[0035] A vehicle according to another aspect of this disclosure includes a battery management device according to one aspect of this disclosure.

[0036] A battery management method according to another aspect of this disclosure may include: a profile obtaining step, which obtains a first profile of each of a plurality of batteries included in a battery pack; a target value calculation step, which calculates a target value of each of the plurality of batteries based on a first target point or target ratio of each of the plurality of first profiles; a profile generation step, which generates a distribution profile representing the correspondence between the calculated plurality of target values ​​and the numerical values ​​of each of the plurality of target values; a condition determination step, which determines whether the distribution profile satisfies predetermined conditions; and a state diagnosis step, which diagnoses the state of the battery pack based on the determination result.

[0037] According to another aspect of this disclosure, the recording medium is a non-transitory readable recording medium having a program stored thereon for performing a battery management method, the battery management method comprising: a profile obtaining step, which obtains a first profile of each of a plurality of batteries included in a battery pack; a target value calculation step, which calculates a target value of each of the plurality of batteries based on a first target point or target ratio of each of the plurality of first profiles; a profile generation step, which generates a distribution profile representing the correspondence between the calculated plurality of target values ​​and the numerical values ​​of each of the plurality of target values; a condition determination step, which determines whether the distribution profile satisfies predetermined conditions; and a state diagnosis step, which diagnoses the state of the battery pack based on the determination result.

[0038] Beneficial effects

[0039] According to one aspect of this disclosure, the battery management device according to this disclosure can diagnose the deterioration and imbalance state among multiple batteries included in a battery pack.

[0040] The effects of this disclosure are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art based on the description of the claims. Attached Figure Description

[0041] The accompanying drawings, together with the foregoing disclosure, are used to provide a further understanding of the technical features of this disclosure, and therefore, this disclosure is not to be construed as limited to the drawings.

[0042] Figure 1 This is a schematic diagram illustrating a battery management device according to an embodiment of the present disclosure.

[0043] Figure 2 This is a schematic diagram showing the positive electrode cross-section, negative electrode cross-section, and battery cross-section according to an embodiment of the present disclosure.

[0044] Figure 3 This is a schematic diagram showing a first distribution profile according to an embodiment of the present disclosure.

[0045] Figure 4This is a schematic diagram showing a second distribution profile according to an embodiment of the present disclosure.

[0046] Figure 5 This is a schematic diagram illustrating a reference positive electrode cross-section, a reference negative electrode cross-section, and a reference cross-section according to an embodiment of the present disclosure.

[0047] Figures 6 to 8 This is a diagram used in an example to explain a process for generating a comparison profile for comparison with a battery profile, according to an embodiment of the present disclosure.

[0048] Figures 9 to 11 This is a diagram used in another example to explain the process of generating a comparison profile for comparison with a battery profile according to one embodiment of the present disclosure.

[0049] Figure 12 This is a diagram illustrating an exemplary configuration of a battery pack according to another embodiment of the present disclosure.

[0050] Figure 13 This is a schematic diagram illustrating a vehicle according to another embodiment of the present disclosure.

[0051] Figure 14 This is a schematic diagram illustrating a battery management method according to another embodiment of the present disclosure.

[0052] Figure 15 This is a diagram schematically illustrating the condition determination step and the state diagnosis step of a battery management method according to another embodiment of the present disclosure. Detailed Implementation

[0053] Before the description, it should be understood that the terms used in the specification and appended claims should not be construed as limited to their general and dictionary meanings, but rather as being interpreted based on the meanings and concepts corresponding to the technical aspects of this disclosure, on the basis of the principle that the inventors are allowed to properly define the terms for the best interpretation.

[0054] Therefore, the description presented herein is merely an example for illustrative purposes and is not intended to limit the scope of this disclosure. It should be understood that other equivalents and modifications may be made thereto without departing from the scope of this disclosure.

[0055] Furthermore, in interpreting this disclosure, detailed descriptions will be omitted if it is determined that a description of a relevant known structure or function may obscure the essential points of this disclosure.

[0056] Ordinal terms such as “first” and “second” can be used to distinguish one element from another among various elements, but are not intended to limit these elements by terminology.

[0057] Throughout this specification, when a section is referred to as “comprising” or “including” any element, it means that the section may further include other elements without excluding them, unless otherwise specifically stated.

[0058] Furthermore, throughout the specification, when one part is referred to as "connected" to another part, it is not limited to the case where they are "directly connected," but also includes the case where they are "indirectly connected," in which another element is inserted between them.

[0059] Meanwhile, batteries degrade as they are used, and the degradation state of multiple batteries in a battery pack may differ from one another because the battery pack is repeatedly charged and discharged or left unattended for extended periods. In other words, the degradation state of the multiple batteries in a battery pack may be uneven.

[0060] For example, as batteries deteriorate, their usable capacity decreases. If the degradation of multiple cells in a battery pack is uneven, the usable capacity of each cell may differ. In this case, the usable capacity of the battery pack can be determined based on the minimum usable capacity among the multiple cells.

[0061] Suppose the battery pack consists of 5 cells connected in series, with 4 cells having a usable capacity of 100 Ah and 1 cell having a usable capacity of 90 Ah. In this case, the usable capacity of the battery pack is 450 Ah, not 490 Ah. That is, due to uneven degradation among the multiple cells, there is a problem of 40 Ah of capacity not being utilized.

[0062] This disclosure provides a technique for diagnosing deterioration and imbalance among multiple cells included in a battery pack.

[0063] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0064] Figure 1 This is a schematic diagram illustrating a battery management device 100 according to an embodiment of the present disclosure.

[0065] refer to Figure 1 The battery management device 100 may include a profile acquisition unit 110 and a diagnostic unit 120.

[0066] The profile obtaining unit 110 can be configured to obtain a first profile of each of the plurality of batteries included in the battery pack.

[0067] Here, a battery refers to a physically separable, individual cell with a negative and a positive terminal. As an example, a lithium-ion cell or a lithium polymer cell can be considered a battery. Additionally, batteries can be cylindrical, prismatic, or pouch-shaped. Furthermore, a battery can refer to a battery bank or battery module in which multiple cells are connected in series and / or parallel. In the following text, for ease of explanation, a battery is interpreted as referring to a single, individual cell.

[0068] Here, the first profile is either the positive electrode profile or the negative electrode profile. Furthermore, the reference profile is a profile that is pre-defined as a reference to the first profile. For example, if the first profile is the positive electrode profile, then the reference profile is a reference positive electrode profile. In another example, if the first profile is the negative electrode profile, then the reference profile is a reference negative electrode profile. A detailed description of the reference profile will be given later.

[0069] Figure 2 This is a schematic diagram illustrating the positive electrode cross-section PP, the negative electrode cross-section NP, and the battery cross-section BP according to an embodiment of the present disclosure. Figure 5 This is a schematic diagram illustrating a reference positive electrode cross-section Rp, a reference negative electrode cross-section Rn, and a reference cross-section R according to an embodiment of the present disclosure.

[0070] exist Figure 2 and Figure 5 In this embodiment, the horizontal axis (X-axis) represents capacity (Ah), and the vertical axis (Y-axis) represents voltage (V).

[0071] For example, the profile obtaining unit 110 can obtain a battery profile BP that represents the correspondence between the battery's voltage and capacity, and adjust preset reference positive electrode profile Rp and reference negative electrode profile Rn to correspond to the battery profile BP, so as to obtain positive electrode profile PP and negative electrode profile NP.

[0072] Here, the battery profile BP can be a profile representing the relationship between voltage (V) and capacity (Q) when the battery is being charged. Alternatively, the battery profile BP can be a profile representing the relationship between voltage (V) and capacity (Q) when the battery is being discharged.

[0073] The reference positive electrode profile Rp can be a profile representing the relationship between the capacity and voltage of a preset reference positive electrode cell corresponding to the positive electrode of the battery. For example, the reference positive electrode cell can be the positive electrode of a positive button half-cell or a three-electrode cell. Similarly, the reference negative electrode profile Rn can be a profile representing the relationship between the capacity and voltage of a preset reference negative electrode cell corresponding to the negative electrode of the battery. For example, the reference negative electrode cell can be the negative electrode of a negative button half-cell or a three-electrode cell.

[0074] Specifically, the profile acquisition unit 110 can obtain adjusted positive and negative electrode profiles by adjusting (shifting the profile) or capacity scaling the reference positive electrode profile Rp and the reference negative electrode profile Rn, respectively. Then, the profile acquisition unit 110 can generate comparison profiles by synthesizing (summing capacity values ​​with the same voltage value or summing voltage values ​​with the same capacity value) the adjusted positive and negative electrode profiles. The profile acquisition unit 110 can generate multiple comparison profiles by repeating the adjustment and synthesis processes for the reference positive electrode profile Rp and the reference negative electrode profile Rn. Then, the profile acquisition unit 110 can specify the comparison profile with the smallest error relative to the battery profile BP among the multiple comparison profiles. The profile acquisition unit 110 can determine the adjusted positive and adjusted negative electrode profiles used to generate the specified comparison profiles as the positive electrode profile PP and the negative electrode profile NP of the battery.

[0075] Regarding this, please refer to the following text. Figures 5 to 11 A more specific embodiment is described in which the profile obtaining unit 110 determines the positive electrode profile PP and the negative electrode profile NP.

[0076] As another example, the profile acquisition unit 110 may receive the first profile directly from an external source, rather than generating the first profile itself. For example, the profile acquisition unit 110 may be connected to an external source via a wired and / or wireless connection to receive the first profile.

[0077] The diagnostic unit 120 can be configured to calculate a target value for each of the plurality of cells based on a first target point or target ratio of each of the plurality of first profiles.

[0078] Here, the first target point is the participation start point or participation end point included in the first profile. Specifically, if the first profile is a positive electrode profile, then the first target point is the positive electrode participation start point or positive electrode participation end point. If the first profile is a negative electrode profile, then the first target point is the negative electrode participation start point or negative electrode participation end point.

[0079] The target ratio is the rate of change between the first profile and the reference profile.

[0080] For example, if the first profile is the positive electrode profile, then the target ratio is the positive electrode change rate. The positive electrode change rate refers to the rate of change [%] of the first profile relative to the reference positive electrode profile Rp. Specifically, the positive electrode change rate can be the rate of contraction or expansion of the first profile relative to the reference positive electrode profile Rp. For example, if the first profile contracts by 10% from the reference positive electrode profile Rp, then the positive electrode change rate is 90%. Conversely, if the first profile expands by 10% from the reference positive electrode profile Rp, then the positive electrode change rate is 110%.

[0081] As another example, if the first profile is a negative electrode profile, then the target ratio is the negative electrode change rate. The negative electrode change rate refers to the rate of change [%] of the first profile relative to the reference negative electrode profile Rn. Specifically, the negative electrode change rate can be the rate of contraction or expansion of the first profile relative to the reference negative electrode profile Rn. For example, if the first profile contracts by 10% from the reference negative electrode profile Rn, the negative electrode change rate is 90%. Conversely, if the first profile expands by 10% from the reference negative electrode profile Rn, the negative electrode change rate is 110%.

[0082] The diagnostic unit 120 can be configured to generate a distribution profile representing the correspondence between the generated plurality of target values ​​and the numerical values ​​of each of the plurality of target values.

[0083] Figure 3 This is a schematic diagram illustrating a first distribution profile p1 according to an embodiment of the present disclosure, and Figure 4 This is a schematic diagram illustrating a second distribution profile p2 according to an embodiment of the present disclosure.

[0084] exist Figure 3 and Figure 4 In this embodiment, the horizontal axis (X-axis) represents the target value, and the vertical axis (Y-axis) represents the numerical value of each of the multiple target values.

[0085] As mentioned above, the target value can be used as an indicator of the battery's degradation level, and the distribution profile representing the distribution of multiple target values ​​can be used as a profile representing the uniformity of degradation of multiple batteries.

[0086] The diagnostic unit 120 can be configured to determine whether the distribution profile meets predetermined conditions and to diagnose the state of the battery pack based on the determination result.

[0087] Specifically, the predetermined conditions can be conditions used to determine whether the distribution profile follows a Gaussian distribution. In other words, the predetermined conditions can be conditions used to determine whether the distribution profile exhibits a shape similar to a Gaussian distribution.

[0088] The following is for reference. Figure 3 and Figure 4 A specific example of how the diagnostic unit 120 determines whether the distribution profile meets predetermined conditions.

[0089] If the distribution profile does not meet the predetermined conditions, the diagnostic unit 120 can be configured to diagnose the state of the battery pack as a deteriorated unbalanced state.

[0090] Here, an unbalanced degradation state refers to a state where the degradation state of multiple cells in a battery pack is not uniform. For example, if the degradation state of multiple cells in a battery pack is not uniform, the maximum capacity of each cell may be different.

[0091] On the other hand, a degradation equilibrium state refers to a state in which the degradation state of the multiple cells included in a battery pack can be considered uniform. For example, even if the degradation states of the multiple cells are slightly different, if the difference is so small that it can be ignored, the state of the battery pack can be diagnosed as a degradation equilibrium state.

[0092] As batteries degrade, their usable capacity decreases. If the degradation of multiple cells in a battery pack is uneven, their usable capacities may differ. For example, if the degradation of multiple cells in a battery pack is uneven, their usable capacities may not all be the same. In this case, the usable capacity of the battery pack can be determined based on the minimum usable capacity among the multiple cells.

[0093] For example, suppose a battery pack consists of 5 cells connected in series, with 4 cells having a usable capacity of 100 Ah and 1 cell having a usable capacity of 90 Ah. In this case, the usable capacity of the battery pack is 450 Ah, not 490 Ah. That is, due to uneven degradation of the multiple cells, there is a problem of 40 Ah of capacity being unusable.

[0094] Figure 4 The second distribution profile p2 shown is an example of a distribution profile that does not meet predetermined conditions. The diagnostic unit 120 can diagnose the state of the battery pack corresponding to the second distribution profile p2 as a deteriorated and unbalanced state.

[0095] If the distribution profile meets predetermined conditions, the diagnostic unit 120 can be configured to compare the feature values ​​of the distribution profile with a preset threshold and diagnose the state of the battery pack based on the comparison result.

[0096] Figure 3 The first distribution profile p1 shown is an example of a distribution profile that satisfies predetermined conditions.

[0097] exist Figure 3 In one embodiment, the diagnostic unit 120 can compare the feature value of the first distribution profile p1 with a preset threshold and diagnose the state of the battery pack based on the comparison result.

[0098] Here, an eigenvalue refers to the difference between two target values ​​that have the same corresponding value on a distribution profile. The value (Y-axis value) used to determine the eigenvalue can be preset. For example, an eigenvalue can refer to the full width at half maximum (FWHM). In this case, the value used to determine the eigenvalue can be preset to half the maximum value of the distribution profile. As another example, an eigenvalue can refer to the maximum difference between two target values ​​that have the same corresponding value on a distribution profile. (See reference) Figure 3The eigenvalue of the first distribution profile p1 can be the difference (x2 - x1) between two target values ​​(x1, x2) that have the same corresponding value as k.

[0099] Thresholds can be preset based on the battery pack's BOL (Start of Life) state, the battery pack's current state (e.g., degradation level), reference values ​​derived from a reference group corresponding to the battery pack, or theoretically derived distribution profiles. BOL refers to the battery's initial state, which is the state in which the battery can exhibit maximum capacity and performance when used for the first time after manufacturing.

[0100] Specifically, if the characteristic value exceeds a threshold, the diagnostic unit 120 can be configured to diagnose the state of the battery pack as a degraded unbalanced state. Conversely, if the characteristic value is less than or equal to the threshold, the diagnostic unit 120 can be configured to diagnose the state of the battery pack as a degraded balance state.

[0101] The battery management device 100 according to this disclosure has the advantage that it can diagnose whether the battery pack is in an unbalanced state of degradation by means of the distribution of target values ​​representing the degradation state of the plurality of batteries included in the battery pack.

[0102] Meanwhile, the profile acquisition unit 110 and diagnostic unit 120 included in the battery management device 100 may optionally include processors, application-specific integrated circuits (ASICs), other chipsets, logic circuits, registers, communication modems, data processing devices, etc., known in the art, to execute the various control logics performed in this disclosure. Furthermore, when the control logic is implemented as software, the profile acquisition unit 110 and diagnostic unit 120 can be implemented as a set of program modules. In this case, the program modules can be stored in memory and executed by the profile acquisition unit 110 and diagnostic unit 120. The memory can be internal or external to the battery management device 100 and can be connected to the profile acquisition unit 110 and diagnostic unit 120 by various known means.

[0103] Furthermore, the battery management device 100 may also include a storage unit 130. The storage unit 130 may store data required for the operation and function of various components of the battery management device 100, data generated during the execution of operations or functions, etc. There are no particular limitations on the type of storage unit 130, as long as it is a known information storage device capable of recording, erasing, updating, and retrieving data. As an example, the information storage device may include RAM, flash memory, ROM, EEPROM, registers, etc. In addition, the storage unit 130 may store program code defining the processes that can be executed by the profile acquisition unit 110 and the diagnostic unit 120.

[0104] Specifically, storage unit 130 can store information required by profile acquisition unit 110 to obtain battery profiles. Storage unit 130 can also store information required by diagnostic unit 120 to diagnose the state of the battery pack. For example, storage unit 130 can store reference positive electrode profiles, reference negative electrode profiles, reference capacity, etc. Furthermore, profile acquisition unit 110 and diagnostic unit 120 can access storage unit 130 to obtain the required information. For example, first profiles and first target points of multiple batteries obtained by profile acquisition unit 110 can be stored in storage unit 130, and diagnostic unit 120 can access storage unit 130 to obtain the stored multiple first profiles and multiple first target points.

[0105] According to one embodiment, the diagnostic unit 120 can set a threshold based on the battery pack's degradation level and a preset reference characteristic value. For example, if the diagnostic unit 120 can calculate a value by associating the battery pack's degradation level with a preset reference characteristic value, that value can be applied as a threshold without limitation.

[0106] According to one embodiment, the diagnostic unit 120 can set a threshold by multiplying the degradation level of the battery pack by a preset reference characteristic value.

[0107] The degradation level of a battery pack indicates the extent to which the battery pack has deteriorated. In other words, the degradation level of a battery pack indicates the rate of degradation of the battery pack. Furthermore, the degradation level of a battery pack is the opposite concept to the State of Health (SOH), which indicates the state of health of the battery pack, and can be expressed by the formula (100-SOH)[%]. Here, SOH is estimated based on the ratio of the current values ​​(e.g., capacity, resistance, etc.) of the battery pack to its initial values, and conventional SOH estimation methods can be applied.

[0108] Reference characteristic values ​​can be preset by taking into account the battery pack's BOL state, the characteristic values ​​of the distribution profile, or the battery pack's specifications.

[0109] For example, the specifications of the battery pack can be considered to preset reference characteristic values ​​to specific values. That is, the general values ​​of the specifications of the battery pack to be diagnosed can be preset as reference characteristic values. At the same time, the general values ​​of the battery pack specifications can be preset to correspond to the characteristic values ​​of the battery pack.

[0110] As another example, the reference feature value can be preset as the feature value of a reference distribution profile. Here, the reference distribution profile may refer to a distribution profile obtained from a reference group corresponding to the battery pack. Alternatively, the reference distribution profile may refer to a distribution profile generated when the battery pack is in the BOL state. The feature value of the reference distribution profile is the difference between two target values ​​with the same corresponding value in the reference distribution profile. According to one embodiment, the standard used to determine the feature value of the reference distribution profile may be the same as the standard used to determine the feature value of the distribution profile. Therefore, the feature value of the reference distribution profile and the feature value of the distribution profile determined according to the same standard may be corresponding values.

[0111] A threshold can be set by taking into account the current level of degradation of the battery pack. Therefore, the battery management device 100 has the advantage of being able to more accurately diagnose the state of the battery pack based on a reference (threshold) of the current state of the battery pack.

[0112] The following describes an embodiment in which the diagnostic unit 120 determines whether the distribution profile meets predetermined conditions.

[0113] The diagnostic unit 120 can be configured to calculate a first value and a second value based on multiple target values, and determine whether the distribution profile meets predetermined conditions based on the ratio between the first value and the second value.

[0114] For example, diagnostic unit 120 can calculate a first value and a second value based on a minimum, maximum, and reference value among multiple target values. Specifically, diagnostic unit 120 can determine the minimum, maximum, and reference value from the multiple target values. Diagnostic unit 120 can determine the target value with the largest corresponding value from the multiple target values ​​as the reference value. Furthermore, diagnostic unit 120 can be configured to calculate the difference between the minimum value and the reference value as the first value, and calculate the difference between the reference value and the maximum value as the second value. Finally, diagnostic unit 120 can determine whether the distribution profile meets predetermined conditions based on the ratio between the first value and the second value.

[0115] exist Figure 3 In this embodiment, the diagnostic unit 120 can determine a1 as the minimum value among multiple target values ​​and a3 as the maximum value among multiple target values. Further, the diagnostic unit 120 can determine a2, which has the largest corresponding value among multiple target values, as a reference value. In addition, the diagnostic unit 120 can calculate the difference between a1 and a2 (a2-a1) as a first value, and calculate the difference between a2 and a3 (a3-a2) as a second value. The diagnostic unit 120 can calculate the ratio between the first value (a2-a1) and the second value (a3-a2) as "(a2-a1) ÷ (a3-a2)" or "(a3-a2) ÷ (a2-a1)", and determine whether the distribution profile meets predetermined conditions based on the calculation results.

[0116] For example, if a1 is 11.1%, a2 is 12.1%, and a3 is 13.1%, then the first value is 1% (12.1 - 11.1), and the second value is 1% (13.1 - 12.1). The ratio between the first and second values ​​is 1.

[0117] exist Figure 4 In this embodiment, the diagnostic unit 120 can determine b1 as the minimum value among multiple target values ​​and b3 as the maximum value among multiple target values. Furthermore, the diagnostic unit 120 can determine b2, which has the largest corresponding value among multiple target values, as a reference value. Additionally, the diagnostic unit 120 can calculate the difference between b1 and b2 (b2-b1) as a first value, and calculate the difference between b2 and b3 (b3-b2) as a second value. The diagnostic unit 120 can calculate "(b2-b1) ÷ (b3-b2)" or "(b3-b2) ÷ (b2-b1)" as the ratio between the first value (b2-b1) and the second value (b3-b2), and determine whether the distribution profile meets predetermined conditions based on the calculation results.

[0118] For example, if b1 is 10.1%, b2 is 11.9%, and b3 is 29.2%, then the first value is 1.8% (11.9 - 10.1), and the second value is 17.3% (29.2 - 11.9). The ratio between the first and second values ​​is 9.61 (17.3 ÷ 1.8) or 0.10 (1.8 ÷ 17.3).

[0119] The diagnostic unit 120 can be configured to compare the ratio with a preset threshold ratio segment and determine whether the distribution profile meets a predetermined condition based on the comparison result.

[0120] Specifically, if the calculated ratio falls within a threshold ratio range, the diagnostic unit 120 can determine that the distribution profile meets a predetermined condition. Conversely, if the calculated ratio does not fall within a threshold ratio range, the diagnostic unit 120 can be configured to determine that the distribution profile does not meet a predetermined condition.

[0121] If the ratio between the first value and the second value is greater than or equal to the lower limit of the threshold ratio segment and less than or equal to the upper limit, then the diagnostic unit 120 can determine that the calculated ratio belongs to the threshold ratio segment. Furthermore, the diagnostic unit 120 can determine that the distribution profile meets predetermined conditions. Conversely, if the ratio between the first value and the second value is less than the lower limit or greater than the upper limit, then the diagnostic unit 120 can determine that the ratio does not belong to the threshold ratio segment. Furthermore, the diagnostic unit 120 can determine that the distribution profile does not meet predetermined conditions.

[0122] For example, the lower limit of the threshold ratio segment can be set to 3 ÷ 7, and the upper limit can be set to 7 ÷ 3. That is, the threshold ratio segment can be a preset segment used to check whether the ratio of the first value to the second value is within 3:7 to 7:3. In the following, the lower limit of the threshold ratio segment is described as 3 ÷ 7, and the upper limit is described as 7 ÷ 3, but it should be noted that the specific values ​​are not limited to the embodiments of this disclosure.

[0123] As in the previous embodiments, it is assumed that the lower limit of the threshold ratio segment is set to 3 ÷ 7, and the upper limit is preset to 7 ÷ 3. In this case, Figure 3 In this embodiment, since the ratio between the first value and the second value (first value (1%) ÷ second value (1%) = 1) is greater than or equal to 3 ÷ 7 and less than or equal to 7 ÷ 3, the diagnostic unit 120 can determine that the ratio belongs to the threshold ratio range. Furthermore, the diagnostic unit 120 can determine that the first distribution profile p1 meets predetermined conditions.

[0124] As in the previous embodiments, it is assumed that the lower limit of the threshold ratio segment is preset to 3 ÷ 7, and the upper limit is preset to 7 ÷ 3. In this case, Figure 4 In one embodiment, if the threshold ratio range is preset to be greater than or equal to 3 ÷ 7 and less than or equal to 7 ÷ 3, then the ratio between the first value and the second value (first value (17.3%) ÷ second value (1.8%) = 9.61 or first value (1.8%) ÷ second value (17.3%) = 0.10) is less than 3 ÷ 7 or greater than 7 ÷ 3, and therefore, the diagnostic unit 120 can determine that this ratio does not belong to the threshold ratio range. Furthermore, the diagnostic unit 120 can determine that the second distribution profile p2 does not meet the predetermined conditions.

[0125] The following describes an embodiment in which the diagnostic unit 120 determines the target value based on the first target point.

[0126] In one embodiment, the diagnostic unit 120 may determine the target value based on a reference capacity set for each of the plurality of batteries and a capacity value at a first target point.

[0127] For example, a reference capacity can be set based on the positive electrode profile PP. Specifically, the reference capacity can be set as the positive electrode capacity (Qp), which is the difference between the maximum and minimum capacity of the positive electrode profile PP. As another example, the reference capacity can be set as the negative electrode capacity (Qn), which is the difference between the maximum and minimum capacity of the negative electrode profile NP. As yet another example, the reference capacity can be set as the battery capacity (Qb), which is the difference between the maximum and minimum capacity of the battery profile BP. If the reference capacity is a value representing the state of the battery, various values ​​can be applied, not limited to positive electrode capacity (Qp), negative electrode capacity (Qn), and battery capacity (Qb).

[0128] The diagnostic unit 120 can calculate the SOC (State of Charge) of the first target point based on the ratio of the capacity value of the first target point to the reference capacity, and determine the calculated SOC as the target value. Specifically, the diagnostic unit 120 can calculate the SOC of the first target point by dividing the capacity value of the first target point by the reference capacity, and determine the calculated SOC as the target value. Here, the capacity value of the first target point refers to the capacity value corresponding to the first target point on the first profile line. For example, in Figure 2 In the embodiment, if the first target point is the negative electrode participating in the endpoint, the capacity value of the first target point can be the starting capacity of the first profile NP. Figure 2 4[Ah]) and the first target point ( Figure 2 The capacity of nf) Figure 2 The difference between 50[Ah]).

[0129] In another embodiment, when the first target point is the endpoint of positive electrode participation, the diagnostic unit 120 can determine the positive electrode loss rate as the target value.

[0130] Specifically, the diagnostic unit 120 can calculate the State of Charge (SOC) of the first target point based on the ratio of the capacity value of the first target point to the reference capacity, and calculate the positive electrode loss rate based on a preset first reference value and a second reference value for each of the multiple batteries and the calculated SOC. Then, the diagnostic unit 120 can determine the calculated positive electrode loss rate as the target value. Here, the positive electrode loss rate refers to the positive electrode reaction area of ​​the battery at the time of diagnosis, compared to the positive electrode reaction area of ​​the battery in the BOL state.

[0131] Specifically, the diagnostic unit 120 can calculate the positive electrode loss rate through the following calculation process: The diagnostic unit 120 can calculate a first difference, which is the difference between a first reference value and a second reference value. Then, the diagnostic unit 120 can calculate a second difference, which is the difference between the SOC at the first target point and the first reference value. Finally, the diagnostic unit 120 can calculate the positive electrode loss rate by calculating the ratio of the second difference to the first difference.

[0132] Here, the first reference value can be preset as the SOC at the reference participation endpoint. The SOC at the reference participation endpoint can be calculated by dividing the capacity value at the reference participation endpoint by the reference capacity of the battery in the BOL state. The second reference value can be preset as the SOC at the reference participation start point. That is, the SOC at the reference participation start point can be preset as the value obtained by dividing the capacity value at the reference participation start point by the reference capacity of the battery in the BOL state.

[0133] For example, the reference participation endpoint can be the positive participation endpoint of the positive electrode profile obtained for a battery in the BOL state, and the reference participation start point can be the positive participation start point of the positive electrode profile obtained for a battery in the BOL state.

[0134] For example, the diagnostic unit 120 can use the following formula 1 to calculate the positive electrode loss rate.

[0135] [Formula 1]

[0136]

[0137] Here, L p It is the positive electrode loss rate, and pf MOL pi represents the SOC of the first target point. BOL This indicates the state of charge (SOC) at the positive electrode participation starting point of the positive electrode profile obtained for a battery in the BOL (Boiled-Off) state. pf BOL This indicates the state of charge (SOC) at the end of the positive electrode participation in the positive electrode profile obtained for a battery in the BOL state. Additionally, MOL (Mid-Life) refers to the state of the battery after a certain degree of use, specifically the stage where performance has deteriorated compared to the initial BOL but still maintains normal operation.

[0138] As another example, the reference participation endpoint may include the positive participation start point for the positive electrode profile obtained for a battery in the BOL state and the negative participation endpoint for the negative electrode profile obtained for a battery in the BOL state. The reference participation start point may be the negative participation start point for the negative electrode profile obtained for a battery in the BOL state.

[0139] As another example, the diagnostic unit 120 can use the following formula 2 to calculate the positive electrode loss rate.

[0140] [Formula 2]

[0141]

[0142] Here, L p It is the positive electrode loss rate, and pf MOL This represents the SOC of the first target point. pf BOL This indicates the state of charge (SOC) at the endpoint of the positive electrode profile obtained for a battery in the BOL (Browser-Oriented) state. BOL This indicates the state of charge (SOC) of the negative electrode at the endpoint, as shown in the negative electrode profile obtained for a battery in the BOL state, and ni BOL This indicates the state of charge (SOC) at the negative electrode participation starting point for the negative electrode profile obtained for a battery in the BOL state.

[0143] The positive electrode loss rate (L) was calculated using Formula 1. p ) and the positive electrode loss rate (L) calculated using Formula 2p The same. This is because "pf" BOL -pi BOL "and nf BOL -ni BOL "They have the same value. For example, in..." Figure 2 In the embodiment, due to pf BOL and pi BOL The difference between them and ni BOL and nf BOL The difference between them corresponds to the battery capacity (Qb), therefore the positive electrode loss rate (L) calculated using Formula 1 and Formula 2 is... p ) are the same.

[0144] Meanwhile, since the positive electrode reaction area decreases with battery degradation, the positive electrode capacity participating in the charging or discharging reaction may decrease. Therefore, the positive electrode loss rate—which refers to the positive electrode reaction area of ​​the battery at the time of diagnosis compared to the positive electrode reaction area of ​​a battery in the BOL state—can be used as an indicator of the battery's degradation level. Furthermore, there is a one-to-one correspondence between the positive electrode loss rate and the State of Charge (SOC) at the endpoint of positive electrode participation. This can be confirmed through the positive electrode loss rate calculation process described above. Therefore, the SOC at the endpoint of positive electrode participation can also be used as an indicator of the battery's degradation level. In other words, the target value can be used as an indicator of the battery's degradation level.

[0145] In another embodiment, when the first target point is the positive electrode participation start point, the diagnostic unit can determine the available lithium loss rate as the target value.

[0146] Specifically, the diagnostic unit 120 can calculate the State of Charge (SOC) of the first target point based on the ratio of the capacity value of the first target point to the reference capacity, and calculate the available lithium loss rate based on a preset first reference value and a second reference value for each of the multiple batteries and the calculated SOC. Then, the diagnostic unit 120 can determine the calculated available lithium loss rate as the target value. Here, the available lithium loss rate refers to the available lithium of the battery at the time of diagnosis compared to the available lithium of a battery in a BOL state.

[0147] Specifically, the diagnostic unit 120 can calculate the available lithium loss rate through the following calculation process. The diagnostic unit 120 can calculate a first difference, which is the difference between a first reference value and a second reference value. Then, the diagnostic unit 120 can calculate a second difference, which is the difference between the SOC at the first target point and the second reference value. Finally, the diagnostic unit 120 can calculate the available lithium loss rate by calculating the ratio of the second difference to the first difference.

[0148] Here, the first reference value can be preset as the SOC at the reference participation endpoint. The SOC at the reference participation endpoint can be calculated by dividing the capacity value at the reference participation endpoint by the reference capacity of the battery in the BOL state. The second reference value can be preset as the SOC at the reference participation start point. That is, the SOC at the reference participation start point can be preset as the value obtained by dividing the capacity value at the reference participation start point by the reference capacity of the battery in the BOL state.

[0149] For example, the reference participation endpoint can be the positive participation endpoint of the positive electrode profile obtained for a battery in the BOL state, and the reference participation start point can be the positive participation start point of the positive electrode profile obtained for a battery in the BOL state.

[0150] For example, the diagnostic unit 120 can use the following formula 3 to calculate the available lithium loss rate.

[0151] [Formula 3]

[0152]

[0153] Here, L Li It is the available lithium loss rate, and pi MOL pi represents the SOC of the first target point. BOL This represents the state of charge (SOC) at the positive electrode participation starting point of the positive electrode profile obtained for a battery in the BOL state, and pf BOL This indicates the state of charge (SOC) at the positive electrode participation endpoint of the positive electrode profile obtained for a battery in the BOL state.

[0154] As another example, the reference participation endpoint can be the negative participation endpoint of the negative electrode profile obtained for a battery in the BOL state, and the reference participation start point can include the negative participation start point of the negative electrode profile obtained for a battery in the BOL state and the positive participation start point of the positive electrode profile obtained for a battery in the BOL state.

[0155] For example, the diagnostic unit 120 can use the following formula 4 to calculate the available lithium loss rate.

[0156] [Formula 4]

[0157]

[0158] Here, L Li It is the available lithium loss rate, pi MOL Let pi represent the SOC of the first target point. BOL This represents the state of charge (SOC) at the positive electrode participation starting point of the positive electrode profile obtained for a battery in the BOL state, nf BOL This indicates the state of charge (SOC) of the negative electrode at the endpoint, as shown in the negative electrode profile obtained for a battery in the BOL state, and niBOL This indicates the state of charge (SOC) at the negative electrode participation starting point for the negative electrode profile obtained for a battery in the BOL state.

[0159] Preferably, the available lithium loss rate (L) is calculated using Equation 3. Li ) and the available lithium loss rate (L) calculated using Equation 4 Li The same. This is because "pf" BOL -pi BOL "and nf BOL -ni BOL "They have the same value. For example, in..." Figure 2 In the embodiment, due to pf BOL and pi BOL The difference between them and nf BOL and ni BOL The difference between them corresponds to the battery capacity (Qb), therefore the available lithium loss rate (L) is calculated using Formulas 3 and 4. Li ) are the same.

[0160] Simultaneously, as the battery deteriorates, the amount of usable lithium that can move between the positive and negative electrodes during charging and discharging gradually decreases. For example, as the battery deteriorates, lithium plating (Li plating) may occur, where lithium is deposited on the surface of the negative electrode. If lithium plating occurs, the amount of usable lithium decreases by as much as the lithium deposited on the surface of the negative electrode. Therefore, the usable lithium loss rate can be used as an indicator of the battery's deterioration level. Furthermore, there is a one-to-one correspondence between the usable lithium loss rate and the State of Charge (SOC) at the starting point of positive electrode participation. This can be confirmed through the aforementioned calculation process for the usable lithium loss rate. Therefore, the SOC at the starting point of positive electrode participation can also be used as an indicator of the battery's deterioration level. In other words, a target value can be used as an indicator of the battery's deterioration level.

[0161] The above describes an example of calculating the SOC of the first target point as the target value. However, the target value is not limited to the SOC of the first target point and can be applied in various ways, as long as it is a value that can be specified for the first target point. For example, the capacity value or voltage value of the first target point can also be applied as the target value.

[0162] The following describes an embodiment in which the diagnostic unit 120 determines the target value based on the target ratio.

[0163] In one embodiment, the diagnostic unit can determine the target ratio as a target value.

[0164] For example, when the first profile is a positive electrode profile, the target ratio is the positive electrode change rate. In this case, the diagnostic unit 120 can be configured to calculate the change rate of the first profile relative to the reference positive electrode profile Rp as the target ratio. That is, the diagnostic unit 120 can calculate the change rate of the positive electrode profile PP relative to the reference positive electrode profile Rp as the target ratio. For example, the diagnostic unit 120 can determine the target ratio as a target value. That is, the diagnostic unit 120 can determine the positive electrode change rate as a target value.

[0165] As another example, when the first profile is a negative electrode profile, the target ratio is the negative electrode change rate. In this case, the diagnostic unit 120 can be configured to calculate the change rate of the first profile relative to the reference negative electrode profile Rn as the target ratio. That is, the diagnostic unit 120 can calculate the change rate of the negative electrode profile NP relative to the reference negative electrode profile Rn as the target ratio. For example, the diagnostic unit 120 can determine the target ratio as a target value. That is, the diagnostic unit 120 can determine the negative electrode change rate as a target value.

[0166] In another embodiment, when the target ratio is the positive electrode change rate, the diagnostic unit 120 can determine the positive electrode loss rate as the target value. Specifically, the diagnostic unit 120 can calculate the positive electrode loss rate based on the ratio between a preset reference ratio and the target ratio for each of the multiple batteries, and determine the calculated positive electrode loss rate as the target value.

[0167] Here, the reference ratio is the positive electrode change rate corresponding to a battery in the BOL state. Specifically, the reference ratio is the ratio of the change in the positive electrode profile corresponding to the battery profile of a battery in the BOL state compared to a reference positive electrode profile Rp. Furthermore, the positive electrode loss rate refers to the positive electrode reaction area of ​​the battery at the time of diagnosis, compared to the positive electrode reaction area of ​​a battery in the BOL state.

[0168] Specifically, the diagnostic unit 120 can calculate the positive electrode loss rate through the following calculation process. The diagnostic unit 120 can calculate the positive electrode loss rate based on the value obtained by dividing the target ratio by the reference ratio.

[0169] For example, the diagnostic unit 120 can use the following formula 5 to calculate the positive electrode loss rate.

[0170] [Formula 5]

[0171]

[0172] Here, L p This represents the positive electrode loss rate, ps MOL This represents the target ratio (positive electrode change rate), and ps BOL Indicates a reference ratio.

[0173] Meanwhile, since the positive electrode reaction area decreases as the battery deteriorates, the positive electrode capacity participating in the reaction during charging or discharging may decrease. Therefore, the positive electrode loss rate—which refers to the positive electrode reaction area of ​​the battery at the time of diagnosis compared to the positive electrode reaction area of ​​a battery in BOL state—can be used as an indicator of the battery's degradation level. Furthermore, there is a one-to-one correspondence between the positive electrode loss rate and the positive electrode change rate. This can be confirmed through the positive electrode loss rate calculation process described above. Therefore, the positive electrode change rate can also be used as an indicator of the battery's degradation level. In other words, a target value can be used as an indicator of the battery's degradation level.

[0174] In another embodiment, when the target ratio is the negative electrode change rate, the diagnostic unit 120 can determine the negative electrode loss rate as the target value. Specifically, the diagnostic unit 120 can calculate the negative electrode loss rate based on the ratio between a preset reference ratio and the target ratio for each of the multiple batteries, and determine the calculated negative electrode loss rate as the target value.

[0175] Here, the reference ratio is the negative electrode change rate corresponding to a battery in the BOL state. Specifically, the reference ratio is the ratio of the change in the negative electrode profile corresponding to the battery profile of a battery in the BOL state compared to a reference negative electrode profile Rn. Furthermore, the negative electrode loss rate refers to the negative electrode reaction area of ​​the battery at the time of diagnosis, compared to the negative electrode reaction area of ​​the battery in the BOL state.

[0176] Specifically, the diagnostic unit 120 can calculate the negative electrode loss rate through the following calculation process. The diagnostic unit 120 can calculate the negative electrode loss rate based on the value obtained by dividing the target ratio by the reference ratio.

[0177] For example, the diagnostic unit 120 can use the following formula 6 to calculate the negative electrode loss rate.

[0178] [Formula 6]

[0179]

[0180] Here, L n Represents the negative electrode loss rate, ns MOL Indicates the target ratio, and ns BOL Indicates a reference ratio.

[0181] Meanwhile, since the negative electrode reaction area decreases with battery degradation, the negative electrode capacity participating in the reaction during charging or discharging may decrease. Therefore, the negative electrode loss rate—which refers to the negative electrode reaction area of ​​the battery at the time of diagnosis compared to the negative electrode reaction area of ​​a battery in BOL state—can be used as an indicator of the battery's degradation level. Furthermore, there is a one-to-one correspondence between the negative electrode loss rate and the negative electrode change rate. This can be confirmed through the negative electrode loss rate calculation process described above. Therefore, the negative electrode change rate can also be used as an indicator of the battery's degradation level. In other words, a target value can be used as an indicator of the battery's degradation level.

[0182] The following describes a specific embodiment in which the diagnostic unit 120 determines the target value based on the first target point and the second target point.

[0183] In one embodiment, the diagnostic unit may be configured to determine a target value based on a second target point included in each of a plurality of first profiles, a first target point, and a reference capacity set for each of a plurality of batteries.

[0184] Here, if the first profile is the positive electrode profile, then the second target point can be different from the first target point between the positive electrode participation start point and the positive electrode participation end point. For example, if the first target point is the positive electrode participation start point, then the second target point is the positive electrode participation end point. In another example, if the first target point is the positive electrode participation end point, then the second target point is the positive electrode participation start point.

[0185] If the first profile is a negative electrode profile, then the second target point can be different from the first target point, between the negative electrode participation start point and the negative electrode participation end point. For example, if the first target point is the negative electrode participation start point, then the second target point is the negative electrode participation end point. In another example, if the first target point is the negative electrode participation end point, then the second target point is the negative electrode participation start point.

[0186] The diagnostic unit 120 can be configured to determine a target value based on a reference capacity, a first target point, and a second target point set for each of the multiple batteries.

[0187] As mentioned above, the reference capacity can be set as positive electrode capacity (Qp), negative electrode capacity (Qn), or battery capacity (Qb). If the reference capacity is a value representing the state of the battery, various values ​​can be applied, not limited to positive electrode capacity (Qp), negative electrode capacity (Qn), and battery capacity (Qb).

[0188] For example, the diagnostic unit 120 can calculate the SOC of the second target point based on the ratio of the capacity value of the second target point to the reference capacity, and determine the SOC of the second target point as the target value.

[0189] Specifically, the diagnostic unit 120 can calculate the SOC of the second target point by dividing the capacity value of the second target point by the reference capacity, and determine the calculated SOC as the target value. Here, the capacity value of the second target point refers to the capacity value corresponding to the second target point on the first profile. For example, in Figure 2 In this embodiment, the capacity value of the second target point can be the initial capacity of the first profile NP. Figure 2 4[Ah]) and the second target point ( Figure 2 The capacity of ni) Figure 2 The difference between 5[Ah]).

[0190] As another example, the diagnostic unit 120 can be configured to calculate the SOC of a first target point based on the ratio of the capacity value of a first target point to the reference capacity, calculate the SOC of a second target point based on the ratio of the capacity value of a second target point to the reference capacity, calculate the capacity loss rate based on a first reference value and a second reference value preset for each of the plurality of batteries, the SOC of the first target point and the SOC of the second target point, and determine the calculated capacity loss rate as a target value.

[0191] Specifically, the diagnostic unit 120 can calculate the capacity loss rate through the following calculation process. The diagnostic unit 120 can calculate a first difference, which is the difference between a first reference value and a second reference value. Then, the diagnostic unit 120 can calculate a third difference, which is the difference between the State of Charge (SOC) of a first target point and the State of Charge (SOC) of a second target point. Finally, the diagnostic unit 120 can calculate the capacity loss rate by calculating the ratio of the third difference to the first difference.

[0192] Here, the first reference value can be preset as the SOC at the reference participation endpoint. The SOC at the reference participation endpoint can be calculated by dividing the capacity value at the reference participation endpoint by the reference capacity of the battery in the BOL state. The second reference value can be preset as the SOC at the reference participation start point. That is, the SOC at the reference participation start point can be preset as the value obtained by dividing the capacity value at the reference participation start point by the reference capacity of the battery in the BOL state.

[0193] In one embodiment, the reference participation endpoint may be the positive participation endpoint of the positive electrode profile obtained for a battery in the BOL state, and the reference participation start point may be the positive participation start point of the positive electrode profile obtained for a battery in the BOL state.

[0194] For example, the diagnostic unit 120 can use the following formula 7 to calculate the capacity loss rate.

[0195] [Formula 7]

[0196]

[0197] Here, L Q It is the capacity loss rate, pf MOL Let pi represent the SOC of the second target point. MOL Let pi represent the SOC of the first target point. BOL This represents the state of charge (SOC) at the positive electrode participation starting point of the positive electrode profile obtained for a battery in the BOL state, and pf BOL This indicates the state of charge (SOC) at the positive electrode participation endpoint of the positive electrode profile obtained for a battery in the BOL state.

[0198] As another example, the diagnostic unit 120 can use the following formula 8 to calculate the capacity loss rate.

[0199] [Formula 8]

[0200]

[0201] Among them, L Q It is the capacity loss rate, nf MOL Ni represents the SOC of the first target point. MOL pi represents the SOC of the second target point. BOL This represents the state of charge (SOC) at the positive electrode participation starting point of the positive electrode profile obtained for a battery in the BOL state, and pf BOL This indicates the state of charge (SOC) at the positive electrode participation endpoint of the positive electrode profile obtained for a battery in the BOL state.

[0202] In another embodiment, the reference participation endpoint may be the negative participation endpoint of the negative electrode profile obtained for a battery in the BOL state, and the reference participation start point may be the negative participation start point of the negative electrode profile obtained for a battery in the BOL state.

[0203] For example, the diagnostic unit 120 can use the following formula 9 to calculate the capacity loss rate.

[0204] [Formula 9]

[0205]

[0206] Here, L Q It is the capacity loss rate, pf MOL Let pi represent the SOC of the second target point. MOL Let nf represent the SOC of the first target point. BOL This indicates the state of charge (SOC) of the negative electrode at the endpoint, as shown in the negative electrode profile obtained for a battery in the BOL state, and ni BOL This indicates the state of charge (SOC) at the negative electrode participation starting point for the negative electrode profile obtained for a battery in the BOL state.

[0207] As another example, the diagnostic unit 120 can use the following formula 10 to calculate the capacity loss rate.

[0208] [Formula 10]

[0209]

[0210] Here, L Q It is the capacity loss rate, nf MOL Let ni represent the SOC of the second target point. MOL This represents the State of Charge (SOC) of the first target point. BOL This indicates the state of charge (SOC) of the negative electrode at the endpoint, as shown in the negative electrode profile obtained for a battery in the BOL state, and ni BOL This indicates the state of charge (SOC) at the negative electrode participation starting point for the negative electrode profile obtained for a battery in the BOL state.

[0211] Preferably, the capacity loss rate (L) calculated using each of Formulas 7 to 10 is used. Q All are identical. This is because "pf" BOL -pi BOL "and nf BOL -ni BOL "have the same value, and "pf MOL -pi MOL "and nf MOL -ni MOL "They have the same value."

[0212] The following describes an example in which the profile obtaining unit 110 determines the positive electrode profile PP and the negative electrode profile NP.

[0213] Figure 5 This is a schematic diagram illustrating a reference positive electrode cross-section Rp and a reference negative electrode cross-section Rn according to an embodiment of the present disclosure. Figure 5 In this embodiment, the horizontal axis (X-axis) represents capacity (Ah), and the vertical axis (Y-axis) represents voltage (V).

[0214] Figures 6 to 8 The accompanying drawings are for reference in explaining an example of a process for generating a comparison profile S for comparison with a battery profile BP according to an embodiment of the present disclosure.

[0215] Reference Figures 6 to 8 The process of generating the comparison profile S is described as follows: four points (positive pole starting point pi, positive pole ending point pf, negative pole starting point ni, and negative pole ending point nf) are set as the first routine corresponding to the voltage range of interest (see...). Figure 6 ), and perform the second routine for section shifting (see Figure 7) and the third routine that performs capacity scaling (see Figure 8 In other words, the process for generating a comparison profile S according to an embodiment of this disclosure includes first to third routines.

[0216] Here, the positive electrode participation start point pi refers to the positive electrode point where the reaction begins during the charging process or where the reaction ends during the discharging process. The positive electrode participation end point pf refers to the positive electrode point where the reaction ends during the charging process or where the reaction begins during the discharging process. Similarly, the negative electrode participation start point ni refers to the negative electrode point where the reaction begins during the charging process or where the reaction ends during the discharging process. The negative electrode participation end point nf refers to the negative electrode point where the reaction ends during the charging process or where the reaction begins during the discharging process.

[0217] First, refer to Figure 6 The reference positive electrode profile Rp and the reference negative electrode profile Rn are compared with Figure 5 The same as those shown.

[0218] The profile acquisition unit 110 determines the positive electrode participation start point pi, positive electrode participation end point pf, negative electrode participation start point ni, and negative electrode participation end point nf on the reference positive electrode profile Rp and the reference negative electrode profile Rn.

[0219] The positive electrode participation starting point pi and the negative electrode participation starting point ni depend on the other.

[0220] Preferably, the difference between the voltage at which the positive electrode participates in the initial pi and the voltage at which the negative electrode participates in the initial ni can be set to be equal to the starting voltage (minimum voltage) of the battery profile BP.

[0221] As an example, the profile obtaining unit 110 can divide the positive voltage range from the start point to the end point of the reference positive profile Rp into multiple micro-voltage segments, and then set the boundary point of two adjacent micro-voltage segments as the positive participation start point pi. Each micro-voltage segment can have a predetermined size (e.g., 0.01V). Next, the profile obtaining unit 110 can set the point existing on the reference negative profile Rn and having a voltage smaller than the positive participation start point pi by a first predetermined voltage (e.g., 3V) as the negative participation start point ni.

[0222] As another example, the profile obtaining unit 110 can divide the negative electrode voltage range from the start point to the end point of the reference negative electrode profile Rn into multiple micro-voltage segments of a predetermined size, and then set the boundary point of two adjacent micro-voltage segments among the multiple micro-voltage segments as the negative electrode participation start point ni. Next, the profile obtaining unit 110 can set the point existing on the reference positive electrode profile Rp and having a voltage greater than the negative electrode participation start point ni as the positive electrode participation start point pi.

[0223] The positive electrode participates in the endpoint pf and the negative electrode participates in the endpoint nf, which depends on the other.

[0224] Preferably, the difference between the voltage at the positive electrode participating in the endpoint pf and the voltage at the negative electrode participating in the endpoint nf can be set to be equal to the end voltage (maximum voltage) of the battery profile BP.

[0225] As an example, the profile obtaining unit 110 can divide the positive voltage range from the second set voltage to the endpoint of the reference positive profile Rp into multiple micro-voltage segments of a predetermined size, and then set the boundary point of two adjacent micro-voltage segments among the multiple micro-voltage segments as the positive participation endpoint pf. Next, the profile obtaining unit 110 can set the point existing on the reference negative profile Rn and having a voltage smaller than the second set voltage (e.g., 4V) than the positive participation endpoint pf as the negative participation endpoint nf.

[0226] As another example, the profile obtaining unit 110 can divide the negative electrode voltage range from the start point to the end point of the reference negative electrode profile Rn into multiple micro-voltage segments of a predetermined size, and then set the boundary point of two adjacent micro-voltage segments among the multiple micro-voltage segments as the negative electrode participation endpoint nf. Next, the profile obtaining unit 110 can set the point existing on the reference positive electrode profile Rp and having a second predetermined voltage greater than the negative electrode participation endpoint nf as the positive electrode participation endpoint pf.

[0227] Once the positive electrode participation start point pi, the positive electrode participation end point pf, the negative electrode participation start point ni, and the negative electrode participation end point nf are determined, the profile obtaining unit 110 will shift at least one of the reference positive electrode profile Rp and the reference negative electrode profile Rn to the left or right along the transverse axis.

[0228] Preferably, the differences between the capacity values ​​of the positive electrode participation start point pi and the positive electrode participation end point pf, the differences between the capacity values ​​of the negative electrode participation start point ni and the negative electrode participation end point nf, and the differences between the initial capacity and the final capacity of the battery profile BP can be set to be the same.

[0229] refer to Figure 7 For example, the profile obtaining unit 110 can shift the reference positive electrode profile Rp to the left (towards low capacity) or shift the negative electrode profile Rn to the right (towards high capacity) or both, so that the capacity values ​​of the positive electrode participation start point pi and the negative electrode participation start point ni are matched.

[0230] As another example, the profile obtaining unit 110 can shift the reference positive electrode profile Rp to the left, or shift the reference negative electrode profile Rn to the right, or both, so that the capacity values ​​of the positive electrode participation endpoint pf and the negative electrode participation endpoint nf match.

[0231] Figure 7 This illustrates a situation where, by generating the adjusted positive electrode profile Rp' by simply shifting the reference positive electrode profile Rp to the left, the capacity value of the positive electrode participation starting point pi' matches the capacity value of the negative electrode participation starting point ni. The adjusted positive electrode profile Rp' is the result of applying the adjustment process of the capacity value difference between the left-shifted positive electrode participation starting point pi and the negative electrode participation starting point ni to the reference positive electrode profile Rp. Therefore, the two points pi and pi' differ only in their capacity values ​​and have the same voltage. Similarly, the two points pf and pf' differ only in their capacity values ​​and have the same voltage.

[0232] When at least one of the reference positive electrode profile Rp and the reference negative electrode profile Rn is shifted, the profile obtains the capacity range of at least one of the scaling adjustment result profiles Rp' and Rn of cell 110.

[0233] Preferably, capacity scaling can be performed so that the capacity range between the positive electrode participation start point and the positive electrode participation end point of the adjusted positive electrode profile Rp', the capacity range between the negative electrode participation start point and the negative electrode participation end point of the adjusted negative electrode profile Rn, and the capacity range of the battery profile BP are the same.

[0234] according to Figure 8 In the example shown, the profile obtaining unit 110 performs an additional adjustment process to shrink or expand at least one of the adjusted positive electrode profile Rp' and the reference negative electrode profile Rn along the horizontal axis. That is, the capacity range can be shrunk or expanded while keeping the voltage range of the adjusted positive electrode profile Rp' constant. Alternatively, the capacity range can be shrunk or expanded while keeping the voltage range of the reference negative electrode profile Rn constant.

[0235] refer to Figure 8 The profile obtaining unit 110 can generate an adjusted positive electrode profile Rp" by shrinking or expanding the adjusted positive electrode profile Rp' so that the capacity range between the two points pi' and pf' of the adjusted positive electrode profile Rp' matches the capacity range of the battery profile BP. At this time, one of the two points pi' and pf' can be fixed. Therefore, the capacity range between the two points pi' and pf" of the adjusted positive electrode profile Rp" can match the capacity range of the battery profile BP.

[0236] Furthermore, the profile obtaining unit 110 can generate an adjusted negative electrode profile Rn' by shrinking or expanding the reference negative electrode profile Rn so that the capacity range between the two points ni and nf of the reference negative electrode profile Rn also matches the capacity range of the battery profile BP. In this case, one of the two points ni and nf, ni, can be fixed. Therefore, the capacity range between the two points ni and nf' of the adjusted negative electrode profile Rn' can match the capacity range of the battery profile BP.

[0237] exist Figure 8 In the middle, the adjusted positive electrode profile Rp" is Figure 7 The adjusted positive electrode profile Rp' shown is the result of contraction along the capacity axis, and the adjusted negative electrode profile Rn' is... Figure 6 The reference negative electrode profile Rn shown is the result of expanding along the capacity axis.

[0238] The positive electrode participation endpoint pf" on the adjusted positive electrode profile Rp" corresponds to the positive electrode participation endpoint pf' on the adjusted positive electrode profile Rp'. The negative electrode participation endpoint nf' on the adjusted negative electrode profile Rn' corresponds to the negative electrode participation endpoint nf on the reference negative electrode profile Rn.

[0239] The capacity range between the positive electrode participation start point pi' and the positive electrode participation end point pf" of the adjusted positive electrode profile Rp" matches the capacity range of the battery profile BP. Similarly, the capacity range between the negative electrode participation start point ni and the negative electrode participation end point nf' of the adjusted negative electrode profile Rn' matches the capacity range of the battery profile BP.

[0240] Furthermore, the capacity range between the two points pi' and pf' of the adjusted positive electrode profile Rp" matches the capacity range between the two points ni and nf' of the adjusted negative electrode profile Rn'. The profile obtaining unit 110 can generate a comparison profile S by subtracting the profile between the two points pi' and pf' of the adjusted positive electrode profile Rp" from the profile between the two points ni and nf' of the adjusted negative electrode profile Rn'.

[0241] The profile acquisition unit 110 can calculate and compare the error (profile error) between profile S and battery profile BP.

[0242] In this regard, various methods known at the time of filing of this disclosure can be used to determine the error between two sections, each of which can be represented in a two-dimensional coordinate system. For example, the integral value of the absolute value of the area between the two sections, or RMSE (root mean square error), can be used as the error between the two sections.

[0243] The profile acquisition unit 110 can map and record at least two of the following in storage unit 130: the adjusted positive electrode profile Rp", the adjusted negative electrode profile Rn', the positive electrode participation start point pi', the positive electrode participation end point pf", the negative electrode participation start point ni, the negative electrode participation end point nf', the first scaling factor, the second scaling factor, the comparison profile S, and the profile error. The first scaling factor can represent the ratio of the capacity difference between two points pi' and pf" to the capacity difference between two points pi0 and pf0. The second scaling factor can represent the ratio of the capacity difference between two points ni and nf' to the capacity difference between two points ni0 and nf0.

[0244] The profile acquisition unit 110 can calculate the positive electrode change rate ps based on the reference positive electrode profile Rp and the adjusted positive electrode profile Rp" . Here, the positive electrode change rate ps means the ratio of the change of the adjusted positive electrode profile relative to the reference positive electrode profile. Additionally, the profile acquisition unit 110 can calculate the negative electrode change rate ns based on the reference negative electrode profile Rn and the adjusted positive electrode profile Rn' . Here, the negative electrode change rate ns means the ratio of the change of the adjusted negative electrode profile relative to the reference negative electrode profile.

[0245] For example, the profile obtaining unit 110 can determine the first scaling factor as the positive electrode change rate ps and the second scaling factor as the negative electrode change rate ns.

[0246] As described above, when the positive voltage range of the reference positive electrode profile Rp is divided into multiple micro-voltage segments, the boundary point of two adjacent micro-voltage segments among the multiple micro-voltage segments can be set as the positive electrode participation starting point pi.

[0247] For example, if the positive voltage range of the reference positive electrode profile Rp is divided into 100 micro-voltage ranges, then there can be 100 boundary points that can be set as the starting point pi of positive electrode participation. Alternatively, if the voltage range in the reference positive electrode profile Rp that is greater than or equal to a second set voltage is divided into 40 micro-voltage ranges, then there can be 40 boundary points that can be set as the ending point pf of positive electrode participation. In this case, up to 4000 different comparison profiles can be generated.

[0248] It is easy to understand that as the size of the micro-voltage segment decreases, the number of comparison profiles that can be generated to the maximum extent increases, and conversely, as the size of the micro-voltage segment increases, the number of comparison profiles that can be generated to the maximum extent decreases.

[0249] The profile obtaining unit 110 can identify the minimum profile error among the multiple comparison profiles generated as described above, and then obtain information mapped to the minimum profile error from the storage unit 130 (e.g., at least one of positive electrode participation start point, positive electrode participation end point, negative electrode participation start point, negative electrode participation end point, first scaling factor and second scaling factor).

[0250] if Figure 8 If the comparison profile S shown has the smallest profile error with the battery profile BP, then the adjusted positive electrode profile Rp" can be used as the positive electrode profile PP, and the adjusted negative electrode profile Rn' can be used as the negative electrode profile NP.

[0251] Figures 9 to 11 This is a diagram used in explaining another example of the process for generating a comparison profile U for comparison with a battery profile BP according to an embodiment of the present disclosure. For reference, according to Figures 9 to 11 The embodiments are independent of those based on Figures 6 to 8 Examples of implementations. Therefore, in the description Figures 6 to 8 The embodiments shown and Figures 9 to 11 The terms or symbols commonly used in the embodiments shown should be understood to be limited to each embodiment.

[0252] For reference Figures 9 to 11 The process described for generating the comparison profile U includes performing a fourth routine for capacity scaling (see [link]). Figure 9 The fifth routine (see) sets four points (positive electrode participation start point, positive electrode participation end point, negative electrode participation start point, negative electrode participation end point) to define four points. Figure 10 ) and the sixth routine that performs the profile shift (see Figure 11 In other words, the process of generating the comparison profile U according to another embodiment of this disclosure includes the fourth to sixth routines.

[0253] refer to Figure 9 The reference positive electrode profile Rp and the reference negative electrode profile Rn are compared with Figure 5 The same as those shown.

[0254] The profile obtaining unit 110 generates adjusted positive electrode profile Rp' and adjusted negative electrode profile Rn' by applying a first scaling factor and a second scaling factor selected from the scaling value range to the reference positive electrode profile Rp and the reference negative electrode profile Rn, respectively.

[0255] The scaling range can be predetermined or can vary according to the ratio of the capacity range of the battery profile BP to the capacity range of the reference profile R. As an example, when a first scaling factor and a second scaling factor can be selected from values ​​spaced 0.1% apart within the scaling range (e.g., 90%, 90.1%, 90.2%, ..., 98.9%, 99%), 91 values ​​can be selected as the first and second scaling factors, respectively. In this case, up to 8281 adjusted profile pairs can be generated based on 91 × 91 = 8281 adjustment levels (combinations of the first and second scaling factors). An adjusted profile pair refers to a combination of an adjusted positive electrode profile and an adjusted negative electrode profile.

[0256] Figure 9 The adjusted positive electrode profile Rp' and adjusted negative electrode profile Rn' shown in the figure illustrate examples of the results of applying a first scaling factor and a second scaling factor of less than 100% to the reference positive electrode profile Rp and the reference negative electrode profile Rn, respectively.

[0257] Since the first and second scaling factors are less than 100%, the adjusted positive electrode profile Rp' is a contraction of the reference positive electrode profile Rp along the horizontal axis, and the adjusted negative electrode profile Rn' is also a contraction of the reference negative electrode profile Rn along the horizontal axis. For ease of understanding, the accompanying drawings are illustrated in a form where the starting point of each of the positive electrode profile Rp and the reference negative electrode profile Rn is fixed and the remaining portion decreases to the left along the horizontal axis.

[0258] refer to Figure 10 The profile obtaining unit 110 determines the positive electrode participation start point pi', positive electrode participation end point pf', negative electrode participation start point ni', and negative electrode participation end point nf' on the adjusted positive electrode profile Rp' and the adjusted negative electrode profile Rn'.

[0259] Either the positive electrode participation start point pi' or the negative electrode participation start point ni' can depend on the other. Similarly, either the positive electrode participation endpoint pf' or the negative electrode participation endpoint nf' can depend on the other. Furthermore, either the positive electrode participation start point pi' or the positive electrode participation endpoint pf' can be set based on the other.

[0260] In other words, when any one of the positive electrode participation start point pi', positive electrode participation end point pf', negative electrode participation start point ni', and negative electrode participation end point nf' is set, the remaining three points can be automatically set by the size of the capacity range of the first set voltage, the second set voltage, and / or the battery profile BP (e.g., SOC 0 to 100% charging capacity).

[0261] As an example, the profile obtaining unit 110 can divide the positive voltage range from the start point to the end point (or the second set voltage) of the adjusted positive profile Rp' into multiple micro-voltage segments, and then set the boundary point of two adjacent micro-voltage segments among the multiple micro-voltage segments as the positive participation start point pi'. Next, the profile obtaining unit 110 can set the point existing on the adjusted negative profile Rn' and whose voltage is lower than the positive participation start point pi' by a first set voltage (e.g., 3V) as the negative participation start point ni'.

[0262] As another example, the profile obtaining unit 110 can divide the negative electrode voltage range from the start point to the end point of the adjusted negative electrode profile Rn' into multiple micro-voltage segments of a predetermined size, and then set the boundary point of two adjacent micro-voltage segments among the multiple micro-voltage segments as the negative electrode participation start point ni'. Next, the profile obtaining unit 110 can search for a point on the adjusted positive electrode profile Rp' that has a voltage greater than the negative electrode participation start point ni' as the positive electrode participation start point pi'.

[0263] As another example, the profile obtaining unit 110 can divide the voltage range from the second set voltage to the end point of the adjusted positive electrode profile Rp' into a plurality of micro-voltage segments of predetermined size, and then set the boundary point of two adjacent micro-voltage segments among the plurality of micro-voltage segments as the positive electrode participation end point pf'. Next, the profile obtaining unit 110 can set the point existing on the adjusted negative electrode profile Rn' and which is lower than the voltage of the positive electrode participation end point pf' by the second set voltage (e.g., 4V) as the negative electrode participation end point nf'.

[0264] As another example, the profile obtaining unit 110 can divide the negative electrode voltage range from the start point to the end point of the adjusted negative electrode profile Rn' into multiple micro-voltage segments of predetermined size, and then set the boundary point of two adjacent micro-voltage segments among the multiple micro-voltage segments as the negative electrode participation endpoint nf'. Next, the profile obtaining unit 110 can set the point existing on the adjusted positive electrode profile Rp' and having a voltage greater than the negative electrode participation endpoint nf' by a second predetermined voltage as the positive electrode participation endpoint pf'.

[0265] Once any one of the positive electrode participation start point pi', positive electrode participation end point pf', negative electrode participation start point ni', and negative electrode participation end point nf' is determined, the profile obtaining unit 110 can additionally determine the remaining three points based on the determined point.

[0266] As an example, when the positive electrode participation start point pi' is first determined, the profile obtaining unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is larger than the capacity value of the positive electrode participation start point pi' by the size of the capacity range of the battery profile BP as the positive electrode participation end point pf'. Furthermore, the profile obtaining unit 110 can search for points on the adjusted negative electrode profile Rn' whose voltage is lower than the voltage of the positive electrode participation start point pi' by a first set voltage, and set the searched point as the negative electrode participation start point ni'. Additionally, the profile obtaining unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is larger than the capacity value of the negative electrode participation start point ni' by the size of the capacity range of the battery profile BP as the negative electrode participation end point nf'.

[0267] As another example, when the positive electrode participation endpoint pf' is first determined, the profile obtaining unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is smaller than the capacity value of the positive electrode participation endpoint pf' by the size of the capacity range of the battery profile BP as the positive electrode participation starting point pi'. Furthermore, the profile obtaining unit 110 can search for points on the adjusted negative electrode profile Rn' whose voltage is lower than the voltage of the positive electrode participation endpoint pf' by a second set voltage, and set the searched point as the negative electrode participation endpoint nf'. Additionally, the profile obtaining unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is smaller than the capacity value of the negative electrode participation endpoint nf' by the size of the capacity range of the battery profile BP as the negative electrode participation starting point ni'.

[0268] As another example, when the negative electrode participation start point ni' is determined, the profile obtaining unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is greater than the capacity value of the negative electrode participation start point ni' by the size of the capacity range of the battery profile BP as the negative electrode participation end point nf'. Furthermore, the profile obtaining unit 110 can search for points on the adjusted positive electrode profile Rp' whose voltage is higher than the negative electrode participation start point ni' by a first set voltage, and set the searched point as the positive electrode participation start point pi'. Additionally, the profile obtaining unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is greater than the capacity value of the positive electrode participation start point pi' by the size of the capacity range of the battery profile BP as the positive electrode participation end point pf'.

[0269] As another example, when the negative electrode participation endpoint nf' is determined, the profile obtaining unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is smaller than the capacity value of the negative electrode participation endpoint nf' by the capacity range of the battery profile BP as the negative electrode participation starting point ni'. Furthermore, the profile obtaining unit 110 can search for points on the adjusted positive electrode profile Rp' whose voltage is higher than the negative electrode participation endpoint nf' by a second set voltage, and set the searched point as the positive electrode participation endpoint pf'. Additionally, the profile obtaining unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is smaller than the capacity value of the positive electrode participation endpoint pf' by the capacity range of the battery profile BP as the positive electrode participation starting point pi'.

[0270] Once the positive electrode participation start point pi', positive electrode participation end point pf', negative electrode participation start point ni', and negative electrode participation end point nf' are determined based on the first scaling factor and the second scaling factor, the profile obtaining unit 110 can shift at least one of the adjusted positive electrode profile Rp' and the adjusted negative electrode profile Rn' to the left or right along the horizontal axis, so that the capacity values ​​of the positive electrode participation start point pi' and the negative electrode participation start point ni' match or the capacity values ​​of the positive electrode participation end point pf' and the negative electrode participation end point nf' match.

[0271] Figure 11 The adjusted negative electrode profile Rn" shown is achieved by only... Figure 10 The adjusted negative electrode profile Rn' shown is obtained by shifting it to the right. Therefore, the capacity values ​​of the positive electrode participation start point pi' and the negative electrode participation start point ni" match each other. In this regard, since the capacity difference between the positive electrode participation start point pi' and the positive electrode participation end point pf' is the same as the capacity difference between the negative electrode participation start point ni' and the negative electrode participation end point nf', if the capacity values ​​of the positive electrode participation start point pi' and the negative electrode participation start point ni" match each other, then the capacity values ​​of the positive electrode participation end point pf' and the negative electrode participation end point nf" also match each other.

[0272] refer to Figure 11 The profile obtaining unit 110 can generate a comparison profile U by subtracting the portion of the profile between the two points ni" and nf" of the adjusted negative electrode profile Rn" from the portion of the profile between the two points pi' and pf' of the adjusted positive electrode profile Rp'.

[0273] The profile acquisition unit 110 can calculate and compare the error (profile error) between profile U and battery profile BP.

[0274] The profile acquisition unit 110 can map and record at least two of the adjusted positive electrode profile Rp', adjusted negative electrode profile Rn", positive electrode participation start point pi', positive electrode participation end point pf', negative electrode participation start point ni", negative electrode participation end point nf", first scaling factor, second scaling factor, comparison profile U and profile error to each other in the storage unit 130.

[0275] The profile acquisition unit 110 can calculate the positive electrode change rate ps based on the reference positive electrode profile Rp and the adjusted positive electrode profile Rp'. Here, the positive electrode change rate ps refers to the ratio of the change in the adjusted positive electrode profile relative to the reference positive electrode profile. Furthermore, the profile acquisition unit 110 can calculate the negative electrode change rate ns based on the reference negative electrode profile Rn and the adjusted negative electrode profile Rn". Here, the negative electrode change rate ns refers to the ratio of the change in the adjusted negative electrode profile relative to the reference negative electrode profile.

[0276] For example, the profile obtaining unit 110 can determine the first scaling factor as the positive electrode change rate ps and the second scaling factor as the negative electrode change rate ns.

[0277] As described above, the profile acquisition unit 110 can generate comparison profiles corresponding to each pair of first and second scaling factors selected from the scaling value range. Since the pairs of first and second scaling factors are complex numbers, it is obvious that the comparison profiles will also be generated as complex numbers. The profile acquisition unit 110 can identify the minimum value among the profile errors of the multiple comparison profiles and then obtain information mapped to the minimum profile error from the storage unit 130.

[0278] if Figure 11 If the comparison profile U shown has the smallest profile error in the battery profile BP, then the adjusted positive electrode profile Rp' can be used as the positive electrode profile PP, and the adjusted negative electrode profile Rn" can be used as the negative electrode profile NP.

[0279] The battery management device 100 according to this disclosure can be applied to a battery management system (BMS). That is, the BMS according to this disclosure may include the battery management device 100 described above. In this configuration, at least some of the components of the battery management device 100 can be implemented by supplementing or adding the functionality of components included in a conventional BMS. For example, the profile acquisition unit 110, diagnostic unit 120, and storage unit 130 of the battery management device 100 can be implemented as components of a BMS.

[0280] Furthermore, the battery management device 100 according to this disclosure can be disposed in a battery pack. That is, the battery pack according to this disclosure may include the aforementioned battery management device 100 and at least one battery. In addition, the battery pack may also include electrical components (relays, fuses, etc.) and a housing.

[0281] Figure 12 This is a diagram illustrating an exemplary configuration of a battery pack 10 according to another embodiment of the present disclosure.

[0282] The positive terminal of battery 11 can be connected to the positive terminal P+ of battery pack 10, and the negative terminal of battery 11 can be connected to the negative terminal P- of battery pack 10.

[0283] The measuring unit 12 can be connected to a first sensing line SL1, a second sensing line SL2, and a third sensing line SL3. Specifically, the measuring unit 12 can be connected to the positive terminal of the battery 11 via the first sensing line SL1, and to the negative terminal of the battery 11 via the second sensing line SL2. The measuring unit 12 can measure the voltage of the battery 11 based on the voltage measured at each of the first sensing line SL1 and the second sensing line SL2.

[0284] Furthermore, the measurement unit 12 can be connected to the current measurement unit A via the third sensing line SL3. For example, the current measurement unit A can be an ammeter or a shunt resistor capable of measuring the charging and discharging currents of the battery 11. The measurement unit 12 can calculate the charge amount by measuring the charging current of the battery 11 via the third sensing line SL3. Additionally, the measurement unit 12 can calculate the discharge amount by measuring the discharging current of the battery 11 via the third sensing line SL3.

[0285] One end of an external device (not shown) can be connected to the positive terminal P+ of battery pack 10, and the other end can be connected to the negative terminal P- of battery pack 10. Therefore, the positive terminal of battery 11, the positive terminal P+ of battery pack 10, the external device, the negative terminal P- of battery pack 10, and the negative terminal of battery 11 can be electrically connected.

[0286] For example, an external device could be a charging device or a load that receives power from battery 11, such as the motor of an electric vehicle.

[0287] Figure 13 This is a schematic diagram of a vehicle 1 according to another embodiment of the present disclosure.

[0288] refer to Figure 13 According to one embodiment of the present disclosure, the battery pack 10 can be included in a vehicle 1 such as an electric vehicle (EV) or a hybrid vehicle (HV). Here, the aforementioned battery pack 10 can be used as a battery module 10. Furthermore, the battery pack 10 can supply power to a motor via an inverter disposed in the vehicle 1 to drive the vehicle 1. In addition, the battery pack 10 may include a battery management device 100 according to one embodiment of the present disclosure. That is, the vehicle 1 may include the battery management device 100. In this case, the battery management device 100 may be an on-board device included in the vehicle 1.

[0289] Figure 14 This is a schematic diagram illustrating a battery management method according to another embodiment of the present disclosure, and Figure 15 This is a diagram schematically illustrating the condition determination step and the state diagnosis step of a battery management method according to another embodiment of the present disclosure.

[0290] refer to Figure 14 The battery management method may include a profile acquisition step (S100), a target value calculation step (S200), a profile generation step (S300), a condition determination step (S400), and a state diagnosis step (S500).

[0291] Preferably, each step of the battery management method can be performed by the battery management device 100. In the following description, for ease of explanation, content overlapping with the previously described content will be briefly described or omitted.

[0292] The profile obtaining step (S100) is a step of obtaining a first profile of each of the multiple batteries included in the battery pack, and can be performed by the profile obtaining unit 110.

[0293] Here, the first profile is either the positive electrode profile or the negative electrode profile. The target value calculation step (S200) is a step of calculating the target value of each of the multiple batteries based on the first target point or target ratio of each of the multiple first profiles, and can be executed by the diagnostic unit 120.

[0294] Here, the first target point is the participation start point or participation end point included in the first profile. Specifically, if the first profile is a positive electrode profile, then the first target point is the positive electrode participation start point or positive electrode participation end point. If the first profile is a negative electrode profile, then the first target point is the negative electrode participation start point or negative electrode participation end point.

[0295] The target ratio is the rate of change of the first profile. Specifically, if the first profile is a positive electrode profile, the target ratio is the positive electrode rate of change. If the first profile is a negative electrode profile, the target ratio is the negative electrode rate of change.

[0296] For example, the diagnostic unit 120 can be configured to determine a target value based on the ratio of the capacity value at a first target point to a reference capacity set for each of the plurality of batteries.

[0297] The profile generation step (S300) is a step of generating a distribution profile that represents the correspondence between the generated multiple target values ​​and the numerical values ​​of each of the multiple target values, and can be executed by the diagnostic unit 120.

[0298] The condition determination step (S400) is a step for determining whether the distribution profile meets predetermined conditions, and can be executed by the diagnostic unit 120.

[0299] The status diagnosis step (S500) is a step for diagnosing the status of the battery pack based on the determined results, and can be executed by the diagnosis unit 120.

[0300] In action step (S600), if the diagnosis determines that the battery is in a degraded and unbalanced state, various actions can be taken, which can be performed by the diagnostic unit 120 or a separate control unit (not shown). For example, low-rate charging can be performed when the battery is being charged, the group balancing function can be activated, or an appropriate alarm can be generated to allow the user to access a check service and attempt group balancing, or, if necessary, replace the battery pack. According to one embodiment, the receiver for such alarm output can be an external device managing the battery pack, such as a BMS, server, or user terminal, as well as an external device, display, or audio device for diagnosing the state of the battery pack.

[0301] refer to Figure 15 In step S410, the diagnostic unit 120 can determine whether the distribution profile meets a predetermined condition. Specifically, the predetermined condition can be a condition used to determine whether the distribution profile follows a Gaussian distribution. In other words, the predetermined condition can be a condition used to determine whether the distribution profile exhibits a shape similar to a Gaussian distribution. If the value of step S410 is yes, then step S420 can be executed. If the value of step S410 is no, then step S520 can be executed.

[0302] In step S420, the diagnostic unit 120 can determine whether the characteristic value of the distribution profile is less than or equal to a threshold. The threshold can be preset based on the battery pack's BOL state, the battery pack's current state (e.g., degradation level), a reference value derived from a reference group corresponding to the battery pack, or a theoretically derived distribution profile. If the value of step S420 is yes, then step S510 can be executed. If the value of step S420 is no, then step S520 can be executed.

[0303] refer to Figure 15 In step S510, the diagnostic unit 120 can diagnose the state of the battery pack as a deteriorated equilibrium state. In step S520, the diagnostic unit 120 can diagnose the state of the battery pack as a deteriorated unbalanced state.

[0304] Here, a degradation equilibrium state refers to a state where the degradation state of the multiple cells in the battery pack can be considered uniform. Conversely, a degradation imbalance state refers to a state where the degradation state of the multiple cells in the battery pack can be considered non-uniform.

[0305] The embodiments of this disclosure described above can be implemented not only by apparatus and methods, but also by a program that implements functions corresponding to the configuration of the embodiments of this disclosure, or a recording medium on which the program is recorded. Those skilled in the art can readily implement the program or recording medium from the above description of the embodiments.

[0306] This disclosure has been described in detail. However, it should be understood that while the detailed description and specific examples indicate preferred embodiments of this disclosure, they are given by way of illustration only, as various changes and modifications within the scope of this disclosure will become apparent to those skilled in the art from the detailed description.

[0307] Furthermore, without departing from the technical aspects of this disclosure, those skilled in the art can make many substitutions, modifications and changes to this disclosure, and this disclosure is not limited to the above embodiments and drawings, and each embodiment can be selectively combined in part or in whole to allow various modifications.

[0308] [Explanation of reference numerals in the attached figures]

[0309] 1: Vehicle

[0310] 10: Battery Pack

[0311] 11: Battery

[0312] 12: Measurement Unit

[0313] 100: Battery Management Device

[0314] 110: Sectioning to obtain unit

[0315] 120: Diagnostic Unit

[0316] 130: Storage unit

Claims

1. A battery management device, comprising: A profile obtaining unit is configured to obtain a first profile of each of a plurality of batteries included in a battery pack. as well as A diagnostic unit is configured to calculate a target value for each of the plurality of batteries based on a first target point or target ratio of each of the plurality of first profiles, generate a distribution profile representing the correspondence between the calculated plurality of target values ​​and the numerical value of each of the plurality of target values, determine whether the distribution profile meets predetermined conditions, and diagnose the state of the battery pack based on the determination result.

2. The battery management device according to claim 1, in, The first cross-section is either a positive electrode cross-section or a negative electrode cross-section, and Wherein, the first target point is either the starting point indicating the start of the charging reaction or the end of the discharging reaction in the first profile, or the ending point indicating the end of the charging reaction or the start of the discharging reaction in the first profile.

3. The battery management device according to claim 1, in, The target ratio is the rate of change between the first profile and a preset reference profile.

4. The battery management device according to claim 1, in, The diagnostic unit is configured to diagnose the state of the battery pack as a deteriorated and unbalanced state when the distribution profile does not meet the predetermined conditions.

5. The battery management device according to claim 1, in, The diagnostic unit is configured to compare the feature value of the distribution profile with a preset threshold when the distribution profile meets the predetermined condition, and to diagnose the state of the battery pack based on the comparison result.

6. The battery management device according to claim 5, in, The diagnostic unit is configured as follows: When the characteristic value exceeds the threshold, the state of the battery pack is diagnosed as a deteriorated and unbalanced state, and When the characteristic value is less than or equal to the threshold, the state of the battery pack is diagnosed as a degraded equilibrium state.

7. The battery management device according to claim 5, in, The diagnostic unit is configured to set the threshold based on the degradation level of the battery pack and a preset reference characteristic value.

8. The battery management device according to claim 1, in, The diagnostic unit is configured to calculate a first value and a second value based on the plurality of target values, and to determine whether the distribution profile satisfies the predetermined condition based on the ratio between the first value and the second value.

9. The battery management device according to claim 8, in, The diagnostic unit is configured to determine a minimum value, a maximum value, and a reference value from the plurality of target values, calculate the difference between the minimum value and the reference value as a first value, and calculate the difference between the reference value and the maximum value as a second value.

10. The battery management device according to claim 9, in, The diagnostic unit is configured to determine the target value with the largest corresponding value among the plurality of target values ​​as the reference value.

11. The battery management device according to claim 8, in, The diagnostic unit is configured as follows: When the ratio falls within a preset threshold ratio range, the distribution profile is determined to satisfy the predetermined condition, and When the ratio does not belong to the threshold ratio range, the distribution profile is determined to not meet the predetermined condition.

12. The battery management device according to claim 1, in, The diagnostic unit is configured to calculate the SOC of the first target point based on the ratio of the capacity value of the first target point to a reference capacity set for each of the plurality of batteries, and to determine the calculated SOC as the target value.

13. The battery management device according to claim 1, in, The diagnostic unit is configured to determine the target ratio as the target value.

14. The battery management device according to claim 1, in, The diagnostic unit is configured to determine the target value based on the ratio between a preset reference ratio for each of the plurality of batteries and the target ratio.

15. The battery management device according to claim 1, in, The diagnostic unit is configured to operate functions for resolving the deterioration imbalance or to output an alarm when the state of the battery pack is diagnosed as a deterioration imbalance state.

16. The battery management device according to claim 15, in, The function used to resolve deterioration imbalances is the group balancing function.

17. A battery pack comprising a battery management device according to any one of claims 1 to 16.

18. A vehicle comprising a battery management device according to any one of claims 1 to 16.

19. A battery management method, comprising: The profile obtaining step obtains a first profile of each of the plurality of batteries included in the battery pack. The target value calculation step calculates the target value of each of the plurality of batteries based on a first target point or target ratio of each of the plurality of first profiles. A profile generation step, wherein the profile generation step generates a distribution profile representing the correspondence between a plurality of calculated target values ​​and the numerical value of each of the plurality of target values; The condition determination step determines whether the distribution profile meets predetermined conditions. as well as A condition diagnosis step, which diagnoses the condition of the battery pack based on the determination results.

20. A non-transitory readable recording medium having a program stored thereon for performing a battery management method, the battery management method comprising: The profile obtaining step obtains a first profile of each of the plurality of batteries included in the battery pack. The target value calculation step calculates the target value of each of the plurality of batteries based on a first target point or target ratio of each of the plurality of first profiles; the profile generation step generates a distribution profile representing the correspondence between the calculated plurality of target values ​​and the numerical value of each of the plurality of target values. The condition determination step determines whether the distribution profile meets predetermined conditions. And a status diagnosis step, which diagnoses the status of the battery pack based on the determination results.

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