Battery management device and method thereof

Abstract

A battery management apparatus according to one embodiment of the present disclosure includes: a split line acquisition unit configured to acquire 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 ratio from each of the plurality of first section lines, calculate each target value as a diagnosis factor based on the plurality of calculated target ratios, a distribution profile indicating a correspondence relationship between the plurality of calculated target values and a numerical value of each of the plurality of target values is generated, whether the distribution profile satisfies a predetermined condition is determined, and a state of the battery pack is diagnosed according to a result of the determination.

Description

TECHNICAL FIELD

[0001] The disclosure relates to a battery management device and method, and more particularly to a battery management device and method capable of diagnosing a state of a battery pack.

[0002] This application is based on and claims priority under 35 U.S.C. 119 to Korean Patent Application No. 10-2024-0005648, filed on January 12, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. BACKGROUND

[0003] In recent years, as the demand for portable electronic products such as notebook computers, camcorders, and portable phones has rapidly increased, and as electric vehicles, energy storage batteries, robots, and satellites have been developed vigorously, research on high-performance batteries that allow repeated charging and discharging is actively being conducted.

[0004] Currently, commercially available batteries include, for example, nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium batteries. Among these batteries, lithium batteries have gained considerable attention due to their advantages including a significantly low memory effect to allow a high degree of freedom of charging and discharging, a very low self-discharge rate, and a high energy density, compared to nickel-based batteries.

[0005] Batteries are used in various fields, and in many cases, large-capacity batteries are required in fields in which batteries are recently being widely used, such as electrically driven vehicles or smart grid systems. In order to increase the capacity of a battery pack, a method for increasing the capacity of a secondary battery, that is, a battery cell itself, can be used. However, in this case, there is a disadvantage in that there is a physical limitation to the size expansion of the secondary battery and inconvenience in its management, and the effect of increasing the capacity is not significant. Therefore, a battery pack including a plurality of battery cells connected in series and in parallel is generally widely used. SUMMARY

[0006] TECHNICAL PROBLEM

[0007] The disclosure provides a battery management device and method capable of diagnosing a state of imbalance in deterioration between a plurality of batteries included in a battery pack.

[0008] Other objects and advantages of the disclosure can be understood by the following description, and will be more clearly understood from the embodiments of the disclosure. Also, it will be easily understood that the objects and advantages of the disclosure can be achieved by the means indicated in the patent claims and combinations thereof.

[0009] TECHNICAL PROBLEM TO BE SOLVED

[0010] A battery management apparatus according to one aspect of the present disclosure may include: a profile acquisition unit configured to acquire a first profile of each of a plurality of batteries included in a battery pack; and a diagnostic unit configured to calculate a target ratio based on each of the plurality of first profiles, calculate each target value as a diagnostic factor based on the plurality of calculated target ratios, generate a distribution profile indicating the correspondence between the plurality of calculated 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 profile can be a negative electrode profile, and the target ratio can be the negative electrode change rate, which is the rate of change of the first profile compared to a preset reference negative electrode profile.

[0012] When the distribution profile does not meet the predetermined conditions, the diagnostic unit can be configured to diagnose the state of the battery pack as a deteriorated unbalanced state.

[0013] When the distribution profile meets predetermined conditions, the diagnostic unit 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.

[0014] When the eigenvalue exceeds the threshold, the diagnostic unit can be configured to diagnose the battery pack as a degraded and unbalanced state.

[0015] When the eigenvalue is less than or equal to the threshold, the diagnostic unit can be configured to diagnose the battery pack as a degraded equilibrium state.

[0016] The diagnostic unit can be configured to set thresholds based on the degree of battery pack degradation and preset reference characteristic values.

[0017] The diagnostic unit 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.

[0018] The diagnostic unit can be configured to determine a minimum, a maximum, and a reference value among multiple target values, calculate the difference between the minimum and the reference value as a first value, and calculate the difference between the reference value and the maximum value as a second value.

[0019] The diagnostic unit can be configured to determine the target value with the largest corresponding value among multiple target values ​​as the reference value.

[0020] The diagnostic unit can be configured to compare the ratio with a preset critical ratio range and determine whether the distribution profile meets predetermined conditions based on the comparison results.

[0021] When the ratio falls within the critical ratio range, the diagnostic unit can be configured to determine that the distribution profile meets predetermined conditions.

[0022] When the ratio does not fall within the critical ratio range, the diagnostic unit can be configured to determine that the distribution profile meets predetermined conditions.

[0023] The diagnostic unit can be configured to determine the target ratio as a target value.

[0024] The diagnostic unit can be configured to calculate the negative electrode loss rate based on the ratio between a preset reference ratio and a target ratio for each of the multiple batteries, and to determine the calculated negative electrode loss rate as the target value.

[0025] The diagnostic unit can be configured to operate functions to resolve the imbalance or output an alarm when the battery pack is determined to be in a degraded or unbalanced state.

[0026] The function used to resolve deterioration imbalances can be configured as a group balancing function.

[0027] According to another aspect of this disclosure, a battery pack may include a battery management device according to one aspect of this disclosure.

[0028] A vehicle according to another aspect of this disclosure may include a battery management device according to one aspect of this disclosure.

[0029] A battery management method according to another aspect of this disclosure may include: a profile acquisition step, which acquires a first profile of each of a plurality of batteries included in a battery pack; a target value calculation step, which calculates a target ratio based on each of the plurality of first profiles and calculates each target value as a diagnostic factor based on the calculated plurality of target ratios; a profile generation step, which generates a distribution profile indicating the correspondence between the plurality of calculated target values ​​and the values ​​of each of the plurality of target values; a condition determination step, which determines whether the distribution profile meets predetermined conditions; and a state diagnosis step, which diagnoses the state of the battery pack based on the determination result.

[0030] The battery management method may also include countermeasures steps that activate functions to resolve the imbalance or output alarms when the battery pack is diagnosed as being in a degraded or unbalanced state during a state diagnosis step.

[0031] According to another aspect of this disclosure, the storage medium is a non-transitory readable storage medium storing a program for performing a battery management method, the battery management method comprising: a profile acquisition step, which acquires a first profile of each of a plurality of batteries included in a battery pack; a target value calculation step, which calculates a target ratio based on each of the plurality of first profiles and calculates each target value as a diagnostic factor based on the plurality of calculated target ratios; a profile generation step, which generates a distribution profile indicating the correspondence between the plurality of calculated 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.

[0032] Beneficial effects

[0033] According to one aspect of this disclosure, the battery management device according to this disclosure can diagnose the state of deterioration imbalance among multiple batteries included in a battery pack.

[0034] 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

[0035] The following drawings, which are attached to this specification and together with the detailed description of this disclosure below, are provided to further understand the technical concept of this disclosure, so that this disclosure should not be construed as limited to the content described in these drawings.

[0036] Figure 1 This is a schematic diagram illustrating a battery management device according to an embodiment of the present disclosure.

[0037] Figure 2 This is a schematic diagram showing the positive electrode cross-section and the final point of positive electrode activation according to an embodiment of the present disclosure.

[0038] Figure 3 This is a schematic diagram showing a first distribution profile according to an embodiment of the present disclosure.

[0039] Figure 4 This is a schematic diagram illustrating a second distribution profile according to an embodiment of the present disclosure.

[0040] Figure 5 This is a schematic diagram showing a reference positive electrode cross-section and a reference negative electrode cross-section according to an embodiment of the present disclosure.

[0041] Figures 6 to 8 This is a reference diagram illustrating an example of a process for generating a comparison profile for comparison with a battery profile, according to an embodiment of the present disclosure.

[0042] Figures 9 to 11 This is a reference diagram for explaining another example of the process for generating a comparison profile for comparison with a battery profile according to an embodiment of the present disclosure.

[0043] Figure 12 This is a diagram illustrating an example configuration of a battery pack according to another embodiment of the present disclosure.

[0044] Figure 13 This is a schematic view of a vehicle according to yet another embodiment of the present disclosure.

[0045] Figure 14 This is a schematic diagram illustrating a battery management method according to yet another embodiment of the present disclosure.

[0046] 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

[0047] The terms and words used in the specification and claims should not be construed as limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts consistent with the technical concept of this disclosure, based on the principle that the inventor can appropriately define the concepts of the terms in order to interpret his or her invention in the best possible way.

[0048] Therefore, the embodiments and configurations shown in the drawings in the specification are provided merely as examples and do not represent all the technical concepts of this disclosure. It should be understood that various equivalents and modifications that can replace the technical concepts may exist at the time of filing this application.

[0049] Furthermore, in the description of this disclosure, detailed descriptions of relevant well-known structures or functions are omitted where such interpretations may obscure the nature of this disclosure.

[0050] Ordinal terms such as “first” and “second” can be used to distinguish one element from another among various elements, but these terms are not intended to limit the elements.

[0051] 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.

[0052] 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.

[0053] Typically, batteries degrade as they are used; however, due to factors such as repeated charging and discharging of the battery pack or prolonged storage of the battery pack, the degradation state of each individual cell within the pack may differ from one another. For example, the degradation state of each cell within the pack may not be uniform.

[0054] As batteries degrade, their usable capacity decreases. Therefore, when the degradation of multiple batteries in a battery pack is uneven, the usable capacity of each battery may differ from the others. In this case, the usable capacity of the battery pack can be determined based on the lowest usable capacity among the multiple batteries.

[0055] For example, suppose a battery pack consists of five cells connected in series, four of which have a usable capacity of 100 [Ah], and one of which has a usable capacity of 90 [Ah]. In this case, the usable capacity of the battery pack is 450 [Ah], not 490 [Ah]. This is because 40 [Ah] of capacity is unusable due to uneven degradation among the cells.

[0056] This disclosure provides a technique for diagnosing the deterioration and imbalance among multiple cells included in a battery pack.

[0057] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0058] Figure 1 This is a schematic diagram illustrating a battery management device 100 according to an embodiment of the present disclosure.

[0059] refer to Figure 1 The battery management device 100 may include a profile acquisition unit 110 and a diagnostic unit 120.

[0060] The profile acquisition unit 110 can be configured to acquire a first profile of each of the plurality of batteries included in the battery pack, such as a negative electrode profile.

[0061] Here, a battery refers to a single, physically separable, independent unit comprising a negative terminal and a positive terminal. For example, a battery can be a lithium-ion battery or a lithium polymer battery. Battery types can be cylindrical, prismatic, or pouch-type. 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 described as referring to a single, independent unit.

[0062] Figure 2 This is a schematic diagram illustrating the negative electrode cross-section NP according to an embodiment of the present disclosure. Figure 5This 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.

[0063] 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).

[0064] For example, the profile acquisition unit 110 can acquire a battery profile BP that indicates the correspondence between the battery's voltage and capacity, and adjust a reference positive electrode profile Rp and a reference negative electrode profile Rn that are preset to correspond to the battery profile BP, thereby determining the negative electrode profile NP. Furthermore, the profile acquisition unit 110 can acquire the negative electrode change rate based on the determined negative electrode profile NP.

[0065] Here, the battery profile BP can be a profile indicating the relationship between voltage (V) and capacity (Q) when the battery is charged. Alternatively, the battery profile BP can be a profile indicating the relationship between voltage (V) and capacity (Q) when the battery is discharged.

[0066] The reference positive electrode profile Rp can be a profile indicating the correspondence between the capacity and voltage of a reference positive electrode cell that is preset to correspond 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 triode cell. Similarly, the reference negative electrode profile Rn can be a profile indicating the correspondence between the capacity and voltage of a reference negative electrode cell that is preset to correspond 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 triode cell.

[0067] The profile acquisition unit 110 can acquire adjusted positive and negative electrode profiles by adjusting each of the reference positive electrode profile Rp and the reference negative electrode profile Rn (by shifting the profile or performing capacity scaling on it). The profile acquisition unit 110 can generate comparison profiles by synthesizing the adjusted positive and negative electrode profiles (by summing capacity values ​​for the same voltage value or summing voltage values ​​for the same capacity value). The profile acquisition unit 110 can generate multiple comparison profiles by repeating the adjustment and synthesis processes on the reference positive electrode profile Rp and the reference negative electrode profile Rn. The profile acquisition unit 110 can specify the comparison profile with the minimum tolerance to the battery profile BP among the multiple comparison profiles. Furthermore, 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.

[0068] In this regard, we will refer to... Figures 5 to 11 An embodiment in which the profile acquisition unit 110 determines the negative electrode profile NP is described.

[0069] As another example, the section acquisition unit 110 can receive the first section line directly from the outside, instead of generating the first section line itself. For example, the section acquisition unit 110 can be connected to the outside in a wired and / or wireless manner to receive the first section line.

[0070] The diagnostic unit 120 can be configured to calculate a target ratio based on each of a plurality of first profiles, and to calculate a target value based on the calculated plurality of target ratios.

[0071] Here, the target ratio can be the negative electrode change rate. The negative electrode change rate indicates the rate of change [%] of the negative electrode profile NP compared to the reference negative electrode profile Rn. For example, the negative electrode change rate can be the contraction or expansion rate of the negative electrode profile NP compared to the reference negative electrode profile Rn. For example, when the negative electrode profile NP contracts by 10% from the reference negative electrode profile Rn, the negative electrode change rate is 90%. Conversely, when the negative electrode profile NP expands by 10% from the reference negative electrode profile Rn, the negative electrode change rate is 110%.

[0072] The diagnostic unit 120 can be configured to calculate the rate of change of the first profile line compared to the reference negative electrode profile line Rn as a target ratio. For example, the diagnostic unit 120 can calculate the rate of change of the negative electrode profile line NP compared to the reference negative electrode profile line Rn as a target ratio. For example, the diagnostic unit 120 can determine the target ratio as a target value. Therefore, the diagnostic unit 120 can determine the negative electrode change rate as a target value.

[0073] The diagnostic unit 120 can be configured to generate a distribution profile indicating the correspondence between a plurality of calculated target values ​​and the numerical values ​​of each of the plurality of target values.

[0074] Figure 3 This is a schematic diagram illustrating a first distribution profile p1 according to an embodiment of the present disclosure. Figure 4 This is a schematic diagram illustrating a second distribution profile p2 according to an embodiment of the present disclosure.

[0075] 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.

[0076] As described above, target values ​​can be used as indicators of the degree of battery degradation. Therefore, a distribution profile indicating the distribution of multiple target values ​​can be used as a profile indicating the degree of uniformity of degradation among multiple batteries.

[0077] 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.

[0078] According to one embodiment, the predetermined condition may be a condition used to determine whether the distribution profile follows a Gaussian distribution. That is, the predetermined condition may be a condition used to determine whether the distribution profile exhibits a shape similar to a Gaussian distribution.

[0079] Please refer to later Figure 3 and Figure 4 An embodiment in which the diagnostic unit 120 determines whether the distribution profile meets predetermined conditions is described.

[0080] When 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.

[0081] Degradation imbalance indicates a state where the degradation state of each cell in a battery pack is uneven. For example, when the degradation state of each cell in a battery pack is uneven, the maximum capacity available for each cell may differ.

[0082] Meanwhile, the degradation equilibrium state indicates a state in which the degradation state of each of the multiple cells included in the battery pack is uniform. For example, even when the degradation state of each of the multiple cells is partially different, the state of the battery pack can be diagnosed as a degradation equilibrium state if the degree of difference is minimal and negligible.

[0083] As batteries degrade, their usable capacity decreases. Therefore, when the degradation of multiple cells in a battery pack is uneven, the usable capacity of each cell may differ from the others. For example, when the degradation of multiple cells in a battery pack is uneven, the usable capacities of the multiple cells may not 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.

[0084] For example, suppose a battery pack consists of five cells connected in series, with four of them having a usable capacity of 100 [Ah] and one of them 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 multiple cells, there is a problem of 40 [Ah] of unusable capacity.

[0085] 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.

[0086] When the distribution profile meets predetermined conditions, the diagnostic unit 120 can be configured to compare the feature value of the distribution profile with a preset threshold and diagnose the state of the battery pack based on the comparison result.

[0087] Figure 3 The first distribution profile p1 shown is an example of a distribution profile that satisfies predetermined conditions.

[0088] 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.

[0089] Here, the eigenvalue indicates the difference between two target values ​​with the same corresponding value in the distribution profile. The value (Y-axis value) used to determine the eigenvalue can be preset. For example, the 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 target values ​​in the distribution profile. As another example, the eigenvalue can indicate the maximum difference between two target values ​​with the same corresponding value in the distribution profile. (See reference) Figure 3 The eigenvalue of the first distribution profile p1 can be the difference (x2-x1) between two target values ​​x1 and x2 that have the same corresponding value as k.

[0090] The threshold can be preset based on the battery pack's beginning of life (BOL) state, the battery pack's current state (e.g., degree of degradation), a reference value derived from a reference set corresponding to the battery pack, or a theoretically derived distribution profile. BOL represents the initial state of the battery, which refers to the state in which the battery may exhibit maximum capacity and performance when it is used for the first time after its manufacture.

[0091] According to one embodiment, when the feature 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, when the feature 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.

[0092] The battery management device 100 according to this disclosure has the advantage of being able to 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.

[0093] 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), chipsets, logic circuits, registers, communication modems, and data processing devices 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 located internally or externally to the battery management device 100 and can be connected to the profile acquisition unit 110 and diagnostic unit 120 by various means known in the art.

[0094] In addition, the battery management device 100 may also include a storage unit 130. The storage unit 130 may store data or programs required for the various components of the battery management device 100 to perform operations and functions, or data generated during the performance of operations and functions. The type of storage unit 130 is not particularly limited, as long as it is a known information storage device capable of recording, erasing, updating, and retrieving data. For example, the information storage device may include random access memory (RAM), flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and registers. Furthermore, the storage unit 130 may store program code defining processes that can be executed by the profile acquisition unit 110 and the diagnostic unit 120.

[0095] Storage unit 130 can store information required by profile acquisition unit 110 to acquire 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, and reference ratios. Profile acquisition unit 110 and diagnostic unit 120 can access storage unit 130 to obtain necessary information. For example, target ratios of multiple batteries acquired by profile acquisition unit 110 can be stored in storage unit 130, and diagnostic unit 120 can access storage unit 130 to obtain the multiple target ratios stored therein.

[0096] According to one embodiment, the diagnostic unit 120 can set a threshold based on the degree of degradation of the battery pack and a preset reference characteristic value. For example, a value that can be calculated by the diagnostic unit 120 by associating the degree of degradation of the battery pack with the preset reference characteristic value can be applied as a threshold without limitation.

[0097] According to one embodiment, the diagnostic unit 120 can set a threshold by multiplying the degree of degradation of the battery pack by a preset reference characteristic value.

[0098] The degree of degradation of a battery pack refers to the extent to which the battery pack has deteriorated. In other words, the degree of degradation refers to the rate of degradation of the battery pack. That is, the degree of degradation is the opposite of the State of Health (SOH), which indicates the 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 value (e.g., capacity or resistance) to the initial value of the battery pack, and conventional SOH estimation methods can be applied to it.

[0099] Reference characteristic values ​​can be preset by considering, for example, the BOL state of the battery pack, the characteristic values ​​of the distribution profile, or the specifications of the battery pack.

[0100] For example, reference characteristic values ​​can be preset to specific values ​​considering the specifications of the battery pack. For instance, general values ​​considering the specifications of the battery pack to be diagnosed can be preset as reference characteristic values. Simultaneously, general values ​​considering the specifications of the battery pack can be preset to correspond to the characteristic values ​​of the battery pack.

[0101] As another example, the reference eigenvalue can be preset as the eigenvalue of a reference distribution profile. Here, the reference distribution profile can refer to a distribution profile obtained from a reference group corresponding to the battery pack. Alternatively, the reference distribution profile can refer to a distribution profile generated when the battery pack is in the BOL state. The eigenvalue of the reference distribution profile is the difference between two target values ​​with the same corresponding value on the reference distribution profile. For example, the standard used to determine the eigenvalue of the reference distribution profile can be the same as the standard used to determine the eigenvalue of the distribution profile. Therefore, the eigenvalue of the reference distribution profile determined based on the same standard and the eigenvalue of the distribution profile can be corresponding values.

[0102] A threshold can be set by taking into account the current degree 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 standard (threshold) of the current state of the battery pack.

[0103] In the following, an embodiment in which the diagnostic unit 120 determines whether the distribution profile meets predetermined conditions will be described.

[0104] 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.

[0105] For example, diagnostic unit 120 can calculate a first value and a second value based on the minimum, maximum, and reference values ​​among multiple target values. For example, diagnostic unit 120 can determine the minimum, maximum, and reference values ​​among multiple target values. Diagnostic unit 120 can determine the target value with the largest corresponding value among 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.

[0106] 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. Furthermore, the diagnostic unit 120 can determine a2, which has the largest corresponding value among multiple target values, as a reference value. Additionally, 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.

[0107] For example, when a1 is 11.1%, a2 is 12.1%, and a3 is 13.1%, 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.

[0108] 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 the ratio between the first value (b2-b1) and the second value (b3-b2) as "(b2-b1) ÷ (b3-b2)" or "(b3-b2) ÷ (b2-b1)", and can determine whether the distribution profile meets predetermined conditions based on the calculation results.

[0109] For example, when b1 is 10.1%, b2 is 11.9%, and b3 is 29.2%, 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).

[0110] The diagnostic unit 120 can be configured to compare the ratio with a preset critical ratio range and determine whether the distribution profile meets a predetermined condition based on the comparison result.

[0111] When the calculated ratio falls within the critical ratio range, the diagnostic unit 120 can determine that the distribution profile meets predetermined conditions. Alternatively, when the calculated ratio does not fall within the critical ratio range, the diagnostic unit 120 can be configured to determine that the distribution profile meets predetermined conditions.

[0112] When the ratio between the first value and the second value is equal to or greater than the lower limit of the critical ratio range and less than or equal to the upper limit of the critical ratio range, the diagnostic unit 120 can determine that the calculated ratio falls within the critical ratio range. Then, the diagnostic unit 120 can determine that the distribution profile meets predetermined conditions. Conversely, when the ratio between the first value and the second value is less than the lower limit or exceeds the upper limit, the diagnostic unit 120 can determine that the ratio does not fall within the critical ratio range. Then, the diagnostic unit 120 can determine that the distribution profile does not meet predetermined conditions.

[0113] For example, the lower limit of the critical ratio range can be set to 3 ÷ 7, and the upper limit of the critical ratio range can be set to 7 ÷ 3. That is, the critical ratio range can be a range preset to check whether the ratio of the first value to the second value is included in 3:7 to 7:3. In the following, the lower limit of the critical ratio range is described as 3 ÷ 7, and the upper limit of the critical ratio range is described as 7 ÷ 3, but it should be noted that such values ​​are not limited to the embodiments of this disclosure.

[0114] Similar to the previous embodiments, it is assumed that the lower limit of the critical ratio range is set to 3 ÷ 7, and the upper limit of the critical ratio range 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 equal to or greater than 3 ÷ 7 and less than or equal to 7 ÷ 3, the diagnostic unit 120 can determine that the ratio falls within the critical ratio range. Furthermore, the diagnostic unit 120 can determine that the first distribution profile p1 satisfies predetermined conditions.

[0115] Similar to the previous embodiments, it is assumed that the lower limit of the critical ratio range is set to 3 ÷ 7, and the upper limit of the critical ratio range is preset to 7 ÷ 3. In this case,Figure 4 In one embodiment, when the critical ratio range is preset to be equal to or greater than 3÷7 and less than or equal to 7÷3, 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, allowing the diagnostic unit 120 to determine that the ratio does not fall within the critical ratio range. Furthermore, the diagnostic unit 120 can determine that the second distribution profile p2 does not meet predetermined conditions.

[0116] In the following, an embodiment in which the diagnostic unit 120 calculates the negative electrode loss rate based on a reference ratio and a target ratio and determines the negative electrode loss rate as a target value will be described.

[0117] The diagnostic unit 120 can calculate the negative electrode loss rate based on the ratio between a preset reference ratio and a target ratio for each of the multiple batteries, and determine the calculated negative electrode loss rate as the target value.

[0118] Here, the reference ratio is the negative electrode change rate corresponding to a battery at the beginning of its life (BOL) state. For example, the reference ratio is the rate of change of the negative electrode profile corresponding to the battery profile of a battery at BOL state compared to a reference negative electrode profile Rn. The negative electrode loss rate refers to the negative electrode reaction area of ​​the battery at its diagnosis, compared to the negative electrode reaction area of ​​the battery at BOL state.

[0119] According to one embodiment, 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.

[0120] For example, the diagnostic unit 120 can use the following Equation 1 to calculate the negative electrode loss rate.

[0121] [Equation 1]

[0122] Here, L n For negative electrode loss rate, ns MOL Indicates the target ratio, and ns BOL This indicates a reference ratio. Furthermore, Mid-Life (MOL) refers to a state where the battery has been used to a certain extent, indicating a stage where the battery's performance has deteriorated compared to the Beginning of Life (BOL), but the battery is still functioning normally.

[0123] Meanwhile, since the negative electrode reaction area decreases with battery degradation, the capacity of the negative electrode activated 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 ​​the battery in the BOL state—can be used as an indicator of the degree of battery degradation. 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 degree of battery degradation. For example, a target value can be used as an indicator of the degree of battery degradation.

[0124] According to the present disclosure, the battery management device 100 can diagnose whether the battery pack is in a state of deterioration imbalance by calculating the negative electrode loss rate, which indicates the deterioration state of the battery, as a target value.

[0125] In the following text, an embodiment in which the profile acquisition unit 110 acquires the negative electrode change rate will be described.

[0126] 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).

[0127] Figures 6 to 8 This is a reference diagram used to explain 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.

[0128] The first routine (see) is used to set four points (positive activation initial point pi, positive activation final point pf, negative activation initial point ni, and negative activation final point nf) to correspond to the voltage range of interest. Figure 6 ), the second routine used to perform the section shift (see Figure 7 ) and a third routine for performing capacity scaling (see Figure 8 The sequential execution of ) should be referred to Figures 6 to 8 The process for generating the comparison profile S is explained. According to one embodiment of this disclosure, the process for generating the comparison profile S includes first to third routines.

[0129] Here, the positive electrode activation initial 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 activation final 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 activation initial 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 activation final 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.

[0130] 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.

[0131] The profile acquisition unit 110 determines the positive electrode activation initial point pi, the positive electrode activation final point pf, the negative electrode activation initial point ni, and the negative electrode activation final point nf on the reference positive electrode profile Rp and the reference negative electrode profile Rn.

[0132] One of the positive electrode activation initial point pi and the negative electrode activation initial point ni depends on the other.

[0133] According to one embodiment, the difference between the voltage at the positive electrode activation initial point pi and the voltage at the negative electrode activation initial point ni can be set to be equal to the starting voltage (minimum voltage) of the battery profile BP.

[0134] For example, the profile acquisition unit 110 can divide the positive voltage range from the start point to the end point of the reference positive electrode profile Rp into multiple micro-voltage segments, and then set the boundary point between two adjacent micro-voltage segments as the positive electrode activation initial point pi. Each micro-voltage segment can have a predetermined size (e.g., 0.01V). Then, the profile acquisition unit 110 can set the point on the reference negative electrode profile Rn that has a voltage lower than the voltage of the positive electrode activation initial point pi as the negative electrode activation initial point ni.

[0135] As another example, the profile acquisition 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 between two adjacent micro-voltage segments as the negative electrode activation initial point ni. Then, the profile acquisition unit 110 can set the point on the reference positive electrode profile Rp that has a voltage greater than the voltage of the negative electrode activation initial point ni as the positive electrode activation initial point pi.

[0136] The final activation point pf of the positive electrode and the final activation point nf of the negative electrode depend on the other.

[0137] According to one embodiment, the difference between the voltage at the final activation point pf of the positive electrode and the voltage at the final activation point nf of the negative electrode can be set to be equal to the end voltage (maximum voltage) of the battery profile BP.

[0138] For example, the profile acquisition unit 110 can divide the positive electrode voltage range from the second set voltage to the end point of the reference positive electrode profile Rp into a plurality of micro-voltage segments of a predetermined size, and then set the boundary point between two adjacent micro-voltage segments as the final positive electrode activation point pf. Next, the profile acquisition unit 110 can set the point on the reference negative electrode profile Rn that has a voltage lower than the voltage of the final positive electrode activation point pf as the final negative electrode activation point nf.

[0139] As another example, the profile acquisition 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 between two adjacent micro-voltage segments as the final negative electrode activation point nf. Then, the profile acquisition unit 110 can set the point on the reference positive electrode profile Rp that has a voltage greater than the voltage at the final negative electrode activation point nf as the final positive electrode activation point pf.

[0140] When the initial activation point pi, the final activation point pf, the initial activation point ni, and the final activation point nf of the negative electrode are determined, the profile acquisition unit 110 shifts 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.

[0141] According to one embodiment, the differences between the capacity value at the initial activation point pi of the positive electrode and the capacity value at the final activation point pf of the positive electrode, the differences between the capacity value at the initial activation point ni of the negative electrode and the capacity value at the final activation point nf of the negative electrode, and the differences between the initial capacity of the battery profile BP and the final capacity of the battery profile BP can be set to be the same for each other.

[0142] refer to Figure 7 For example, the profile acquisition unit 110 can shift the reference positive electrode profile Rp to the left (towards the low capacity side) or shift the reference negative electrode profile Rn to the right (towards the high capacity side), or both, so that the capacity values ​​of the positive electrode activation initial point pi and the negative electrode activation initial point ni coincide with each other.

[0143] As another example, the profile acquisition 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 activation final point pf and the negative electrode activation final point nf coincide with each other.

[0144] Figure 7 This illustrates a situation where, by generating the adjusted positive electrode profile Rp' by shifting the reference positive electrode profile Rp to the left, the capacity value of the initial positive electrode activation point pi' coincides with the capacity value of the initial negative electrode activation point ni. The adjusted positive electrode profile Rp' is the result of applying an adjustment process that performs a leftward shift of the capacity value difference between the initial positive electrode activation points pi and ni to the reference positive electrode profile Rp. Therefore, only the capacity values ​​of the two points pi and pi' differ from each other, and the voltages of the two points pi and pi' are the same. Similarly, only the capacity values ​​of the two points pf and pf' differ from each other, and the voltages of the two points pf and pf' are the same.

[0145] When at least one of the reference positive electrode profile Rp and the reference negative electrode profile Rn has been shifted and the adjusted profiles Rp' and Rn are fixed, the profile acquisition unit 110 scales the capacity range of at least one of the adjusted profiles Rp' and Rn.

[0146] According to one embodiment, capacity scaling can be performed such that the capacity range between the initial and final activation points of the adjusted positive electrode profile Rp', the capacity range between the initial and final activation points of the adjusted negative electrode profile Rn, and the capacity range of the battery profile BP are the same.

[0147] according to Figure 8 In the example shown, the profile acquisition unit 110 performs an additional adjustment process (capacity scaling) for shrinking or expanding 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 of the adjusted positive electrode profile Rp' can be shrunk or expanded, while the voltage range of the adjusted positive electrode profile Rp' remains constant. Alternatively, the capacity range of the reference negative electrode profile Rn can be shrunk or expanded, while the voltage range of the reference negative electrode profile Rn remains constant.

[0148] refer to Figure 8 The profile acquisition 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' coincides with the capacity range of the battery profile BP. In this case, 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 coincide with the capacity range of the battery profile BP.

[0149] Furthermore, the profile acquisition 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 coincides with the capacity range of the battery profile BP. In this case, one of the two points ni and nf can be fixed. Therefore, the capacity range between the two points ni and nf' of the adjusted negative electrode profile Rn' can coincide with the capacity range of the battery profile BP.

[0150] exist Figure 8 In the middle, the adjusted positive electrode profile Rp'' contracts along the capacity axis. Figure 7 The results of the adjusted positive electrode profile Rp' shown are illustrated, and the adjusted negative electrode profile Rn' is an expansion along the capacity axis. Figure 6 The result of the reference negative electrode profile Rn shown.

[0151] The final activation point pf'' on the adjusted positive electrode profile Rp'' corresponds to the final activation point pf' on the adjusted positive electrode profile Rp'. The final activation point nf' on the adjusted negative electrode profile Rn' corresponds to the final activation point nf on the reference negative electrode profile Rn.

[0152] The capacity range between the initial activation point pi' and the final activation point pf'' of the adjusted positive electrode profile Rp'' coincides with the capacity range of the battery profile BP. Similarly, the capacity range between the initial activation point ni and the final activation point nf' of the adjusted negative electrode profile Rn' coincides with the capacity range of the battery profile BP.

[0153] Furthermore, the capacity range between the two points pi' and pf'' of the adjusted positive electrode profile Rp'' coincides with the capacity range between the two points ni and nf' of the adjusted negative electrode profile Rn'. The profile acquisition 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'.

[0154] The profile acquisition unit 110 can calculate and compare the error (profile error) between profile S and battery profile BP.

[0155] 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 the root mean square error (RMSE), can be used as the error between the two sections.

[0156] The profile acquisition unit 110 can map at least two of the following: the adjusted positive electrode profile Rp'', the adjusted negative electrode profile Rn', the positive electrode activation initial point pi', the positive electrode activation final point pf'', the negative electrode activation initial point ni, the negative electrode activation final point nf', a first scaling factor, a second scaling factor, a comparison profile S, and a profile error, and record them in the storage unit 130. The first scaling factor can indicate 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 indicate the ratio of the capacity difference between two points ni and nf' to the capacity difference between two points ni0 and nf0.

[0157] 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 represents the change rate between the adjusted positive electrode profile and the reference positive electrode profile. 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 indicates the change rate between the adjusted negative electrode profile and the reference negative electrode profile.

[0158] For example, the profile acquisition unit 110 can determine the first scaling factor as the positive change rate ps and the second scaling factor as the negative change rate ns.

[0159] 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 between two adjacent micro-voltage segments can be set as the initial positive electrode activation point pi.

[0160] For example, when the positive voltage range of the reference positive electrode profile Rp is divided into 100 micro-voltage ranges, the number of boundary points that can be set as the initial positive electrode activation point pi can be 100. Furthermore, when the voltage range in the reference positive electrode profile Rp that is equal to or greater than the second set voltage is divided into 40 micro-voltage ranges, the number of boundary points that can be set as the final positive electrode activation point pf can be 40. In this case, up to 4000 different comparison profiles can be generated.

[0161] Those skilled in the art will readily understand that as the size of the micro-voltage segment decreases, the maximum number of comparison profiles that can be generated will increase, and conversely, as the size of the micro-voltage segment increases, the maximum number of comparison profiles that can be generated will decrease.

[0162] The profile acquisition 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 the positive electrode activation initial point, positive electrode activation final point, negative electrode activation initial point, negative electrode activation final point, first scaling factor and second scaling factor).

[0163] when Figure 8 When the comparison of the complete single-cell profile S and the battery profile BP shown has the minimum profile error, the adjusted reference negative electrode profile Rn' can be used as the negative electrode profile NP.

[0164] Figures 9 to 11 This is a reference diagram used to explain 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 The embodiments are as follows. Therefore, in explaining according to Figures 6 to 8 Implementation examples and according to Figures 9 to 11 The terms or symbols commonly described in the embodiments should be understood as being limited to the respective embodiments.

[0165] According to the fourth routine used to perform capacity scaling (see...) Figure 9 The fifth routine (see) is used to set four points (positive electrode activation initial point, positive electrode activation final point, negative electrode activation initial point, and negative electrode activation final point). Figure 10 ) and the sixth routine used to perform the profile shift (see Figure 11 The sequential execution of ) should be referred to Figures 9 to 11 The process for generating the comparison profile U is described. That is, the process for generating the comparison profile U according to another embodiment of this disclosure includes fourth to sixth routines.

[0166] 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.

[0167] The profile acquisition unit 110 applies 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, to generate the adjusted positive electrode profile Rp' and the adjusted negative electrode profile Rn'.

[0168] The scaling range can be predetermined or vary according to the ratio of the capacity range of the battery profile BP to the capacity range of the reference profile R. For example, when selecting a first scaling factor and a second scaling factor from values ​​spaced 0.1% apart within the scaling range (e.g., 90% to 99%), 91 values ​​can be selected as the first and second scaling factors, respectively. In this case, up to 8281 pairs of adjusted profiles can be generated based on 91 × 91 = 8281 adjustment levels (combinations of the first and second scaling factors). Each pair of adjusted profiles refers to a combination of an adjusted positive electrode profile and an adjusted negative electrode profile.

[0169] Figure 9 The adjusted positive electrode profile Rp' and adjusted negative electrode profile Rn' shown in the figure illustrate the results of applying a first scaling factor of less than 100% and a second scaling factor of less than 100% to the reference positive electrode profile Rp and the reference negative electrode profile Rn, respectively.

[0170] Since the first and second scaling factors are less than 100%, the adjusted positive electrode profile Rp' is obtained by shrinking the reference positive electrode profile Rp along the horizontal axis, and the adjusted negative electrode profile Rn' is also obtained by shrinking the reference negative electrode profile Rn along the horizontal axis. To aid understanding, an example is shown where the starting point of each of the reference positive electrode profile Rp and the reference negative electrode profile Rn is fixed, and only their remaining portions decrease to the left along the horizontal axis.

[0171] refer to Figure 10 The profile acquisition unit 110 determines the positive electrode activation initial point pi', positive electrode activation final point pf', negative electrode activation initial point ni', and negative electrode activation final point nf' on the adjusted positive electrode profile Rp' and the adjusted negative electrode profile Rn'.

[0172] One of the positive electrode activation initial point pi' and the negative electrode activation initial point ni' can depend on the other. Furthermore, one of the positive electrode activation final point pf' and the negative electrode activation final point nf' can depend on the other. Additionally, one of the positive electrode activation initial point pi' and the positive electrode activation final point pf' can be set based on the other.

[0173] For example, when one of the positive electrode activation initial point pi', positive electrode activation final point pf', negative electrode activation initial point ni', and negative electrode activation final point nf' is set, the remaining three points can be automatically set by the size of the first set voltage, the second set voltage, and / or the capacity range of the battery profile BP (e.g., the charging capacity from 0% to 100% SOC).

[0174] For example, the profile acquisition unit 110 can divide the positive electrode voltage range from the start point to the end point (or the second set voltage) of the adjusted positive electrode profile Rp' into multiple micro-voltage segments, and then set the boundary point between two adjacent micro-voltage segments as the positive electrode activation initial point pi'. Then, the profile acquisition unit 110 can set the point that exists on the adjusted negative electrode profile Rn and has a voltage lower than the positive electrode activation initial point pi' as the negative electrode activation initial point ni'.

[0175] As another example, the profile acquisition 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 between two adjacent micro-voltage segments as the negative electrode activation initial point ni'. Then, the profile acquisition unit 110 can set the point on the adjusted positive electrode profile Rp' that has a voltage greater than the negative electrode activation initial point ni' as the positive electrode activation initial point pi'.

[0176] As another example, the profile acquisition 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 a predetermined size, and then set the boundary point between two adjacent micro-voltage segments as the final positive electrode activation point pf'. Then, the profile acquisition unit 110 can set the point on the adjusted negative electrode profile Rn' that has a voltage lower than the voltage of the final positive electrode activation point pf' by the second set voltage (e.g., 4V) as the final negative electrode activation point nf'.

[0177] As another example, the profile acquisition 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 between two adjacent micro-voltage segments as the final negative electrode activation point nf'. Then, the profile acquisition unit 110 can set the point on the adjusted positive electrode profile Rp' that has a voltage greater than the voltage at the final negative electrode activation point nf' as the final positive electrode activation point pf'.

[0178] Once one of the positive electrode activation initial point pi', positive electrode activation final point pf', negative electrode activation initial point ni', and negative electrode activation final point nf' is determined, the profile acquisition unit 110 can additionally determine the remaining three points based on the determined point.

[0179] For example, when the initial positive electrode activation point pi' is first determined, the profile acquisition unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is greater than the capacity value of the initial positive electrode activation point pi' by the size of the capacity range of the battery profile BP as the final positive electrode activation point pf'. Furthermore, the profile acquisition unit 110 can search for points on the adjusted negative electrode profile Rn' whose voltage is lower than the voltage of the initial positive electrode activation point pi' by a first set voltage, and set the searched point as the initial negative electrode activation point ni'. Additionally, the profile acquisition unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is greater than the capacity value of the initial negative electrode activation point ni' by the size of the capacity range of the battery profile BP as the final negative electrode activation point nf'.

[0180] As another example, when the final activation point pf' of the positive electrode is first determined, the profile acquisition unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is smaller than the capacity value of the final activation point pf' by the size of the capacity range of the battery profile BP as the initial activation point pi' of the positive electrode. Furthermore, the profile acquisition unit 110 can search for points on the adjusted negative electrode profile Rn' whose voltage is lower than the voltage of the final activation point pf' by a second set voltage, and set the searched point as the final activation point nf' of the negative electrode. Additionally, the profile acquisition unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is smaller than the capacity value of the final activation point nf' by the size of the capacity range of the battery profile BP as the initial activation point ni' of the negative electrode.

[0181] As another example, when the initial negative electrode activation point ni' is determined, the profile acquisition unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is greater than the capacity value of the initial negative electrode activation point ni' by the size of the capacity range of the battery profile BP as the final negative electrode activation point nf'. Furthermore, the profile acquisition unit 110 can search for points on the adjusted positive electrode profile Rp' whose voltage is higher than the voltage of the initial negative electrode activation point ni' by a first set voltage, and set the searched point as the initial positive electrode activation point pi'. Additionally, the profile acquisition unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is greater than the capacity value of the initial positive electrode activation point pi' by the size of the capacity range of the battery profile BP as the final positive electrode activation point pf'.

[0182] As another example, when the final activation point nf' of the negative electrode is determined, the profile acquisition unit 110 can set the point on the adjusted negative electrode profile Rn' whose capacity value is smaller than the capacity value of the final activation point nf' by the size of the capacity range of the battery profile BP as the initial activation point ni' of the negative electrode. Furthermore, the profile acquisition unit 110 can search for points on the adjusted positive electrode profile Rp' whose voltage is higher than the voltage of the final activation point nf' by a second set voltage, and set the searched point as the final activation point pf' of the positive electrode. Additionally, the profile acquisition unit 110 can set the point on the adjusted positive electrode profile Rp' whose capacity value is smaller than the capacity value of the final activation point pf' by the size of the capacity range of the battery profile BP as the initial activation point pi' of the positive electrode.

[0183] When the determination of the positive electrode activation initial point pi', the positive electrode activation final point pf', the negative electrode activation initial point ni', and the negative electrode activation final point nf' is completed based on the first scaling factor and the second scaling factor, the profile acquisition 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 activation initial point pi' and the negative electrode activation initial point ni' coincide with each other, or the capacity values ​​of the positive electrode activation final point pf' and the negative electrode activation final point nf' coincide with each other.

[0184] Figure 11 The adjusted negative electrode profile Rn" shown is achieved by only using Figure 10 The adjusted negative electrode profile Rn' shown is formed by shifting it to the right. Therefore, the capacity values ​​of the positive electrode activation initial point pi' and the negative electrode activation initial point ni" coincide with each other. In this respect, since the capacity difference between the positive electrode activation initial point pi' and the positive electrode activation final point pf' is the same as the capacity difference between the negative electrode activation initial point ni' and the negative electrode activation final point nf', when the capacity values ​​of the positive electrode activation initial point pi' and the negative electrode activation initial point ni" coincide with each other, the capacity values ​​of the positive electrode activation final point pf' and the negative electrode activation final point nf" also coincide with each other.

[0185] refer to Figure 11 The profile acquisition 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 positive electrode profile Rp' from the portion of the profile between the two points pi' and pf' of the adjusted negative electrode profile Rn".

[0186] The profile acquisition unit 110 can calculate and compare the error (profile error) between profile U and battery profile BP.

[0187] The profile acquisition unit 110 can map at least two of the adjusted positive electrode profile Rp', the adjusted negative electrode profile Rn", the positive electrode activation initial point pi', the positive electrode activation final point pf', the negative electrode activation initial point ni", the negative electrode activation final point nf", the first scaling factor, the second scaling factor, the comparison profile U and the profile error to each other, and record them in the storage unit 130.

[0188] 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 represents the change rate between the adjusted positive electrode profile and the reference positive electrode profile. 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 indicates the change rate between the adjusted negative electrode profile and the reference negative electrode profile.

[0189] For example, the profile acquisition 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.

[0190] 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 there are multiple pairs of first and second scaling factors, it is obvious that multiple comparison profiles will also be generated. The profile acquisition unit 110 can identify the minimum value of the profile error among the multiple comparison profiles, and then obtain information mapped to the minimum profile error from the storage unit 130.

[0191] when Figure 11 When the comparison of the full-cell profile U and the battery profile BP shown has the minimum profile error, the adjusted reference negative electrode profile Rn'' can be used as the negative electrode profile NP.

[0192] 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 corresponding 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.

[0193] 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 one or more batteries. In addition, the battery pack may also include electrical components (relays and fuses) and a housing.

[0194] Figure 12 This is a diagram illustrating an example configuration of a battery pack 10 according to another embodiment of the present disclosure.

[0195] 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.

[0196] The measurement unit 12 can be connected to a first sensing line SL1, a second sensing line SL2, and a third sensing line SL3. For example, the measurement 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 measurement unit 12 can measure the voltage of the battery 11 based on the voltage measured from each of the first sensing line SL1 and the second sensing line SL2.

[0197] 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 current and discharging current of the battery 11. The measurement unit 12 can measure the charging current of the battery 11 via the third sensing line SL3 to calculate the amount of charge. In addition, the measurement unit 12 can measure the discharging current of the battery 11 via the third sensing line SL3 to calculate the amount of discharge.

[0198] An external device (not shown) may have one end connected to the positive terminal P+ of the battery pack 10 and the other end connected to the negative terminal P- of the battery pack 10. Therefore, the positive terminal of the battery 11, the positive terminal P+ of the battery pack 10, the external device, the negative terminal P- of the battery pack 10, and the negative terminal of the battery 11 can be electrically connected to each other.

[0199] For example, an external device could be a charger or load that receives power from battery 11, such as the motor of an electric vehicle.

[0200] Figure 13 This is a schematic view of a vehicle 1 according to yet another embodiment of the present disclosure.

[0201] refer to Figure 13 The battery pack 10 according to embodiments of the present disclosure can be included in a vehicle 1 such as an electric vehicle (EV) or a hybrid vehicle (HV). Here, the battery pack 10 can be the aforementioned battery pack 10. The battery pack 10 can supply power to the vehicle's motor via an inverter equipped in the vehicle 1 to drive the vehicle 1. Here, the battery pack 10 can include a battery management device 100 according to embodiments of the present disclosure. That is, the vehicle 1 can include the battery management device 100. In this case, the battery management device 100 can be an on-board device included in the vehicle 1.

[0202] Figure 14This is a schematic diagram illustrating a battery management method according to yet another embodiment of the present disclosure. 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.

[0203] 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.

[0204] Each step of the battery management method can be performed by the battery management device 100. In the following text, for ease of explanation, content overlapping with the foregoing will be omitted or briefly described.

[0205] The profile acquisition step S100 is a step of acquiring the first profile of each of the multiple batteries included in the battery pack, and can be executed by the profile acquisition unit 110.

[0206] The target value calculation step S200 is a step of calculating a target ratio based on each of the plurality of first profiles and calculating a target value based on the calculated target ratio, and can be executed by the diagnostic unit 120.

[0207] Here, the target ratio can be the negative pole change rate.

[0208] The diagnostic unit 120 can determine the target ratio by calculating the rate of change between the negative electrode profile and the reference negative electrode profile.

[0209] For example, the diagnostic unit 120 can be configured to determine the target ratio as a target value.

[0210] As another example, the diagnostic unit 120 can be configured to calculate the negative electrode loss rate based on the ratio between a preset reference ratio and a target ratio for each of the multiple batteries, and to determine the calculated negative electrode loss rate as the target value.

[0211] The profile generation step S300 is a step of generating a distribution profile that indicates the correspondence between a plurality of calculated target values ​​and the numerical values ​​of each of the plurality of target values, and can be performed by the diagnostic unit 120.

[0212] The condition determination step S400 is a step to determine whether the distribution profile meets the predetermined conditions, and can be executed by the diagnostic unit 120.

[0213] The status diagnosis step S500 is a step to diagnose the status of the battery pack based on the determination result, and can be executed by the diagnosis unit 120.

[0214] Countermeasure step S600 is a series of steps taken when the battery is determined to be in a degraded and unbalanced state based on diagnostic results, and can be executed by the diagnostic unit 120 or a separate control unit (not shown). For example, low-rate charging can be performed during battery charging, or the battery pack balancing function can be activated, or the user can access a check service by receiving an appropriate alarm and attempt battery pack balancing or replacement if necessary. 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, or may include an external device, display, or audio device for diagnosing the state of the battery pack.

[0215] refer to Figure 15 In step S410, the diagnostic unit 120 can determine whether the distribution profile meets a predetermined condition. For example, the predetermined condition can be a condition used to determine whether the distribution profile follows a Gaussian distribution. That is, the predetermined condition can be a condition used to determine whether the distribution profile exhibits a shape similar to a Gaussian distribution. When the value of step S410 is yes, step S420 can be executed. When the value of step S410 is no, step S520 can be executed.

[0216] 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 life start (BOL) state, the battery pack's current state (e.g., degree of degradation), a reference value derived from a reference group corresponding to the battery pack, or a theoretically derived distribution profile. When the value of step S420 is yes, step S510 can be executed. When the value of step S420 is no, step S520 can be executed.

[0217] refer to Figure 15 In step S510, the diagnostic unit 120 can diagnose the state of the battery pack as a degraded equilibrium state. In step S520, the diagnostic unit 120 can diagnose the state of the battery pack as a degraded unbalanced state.

[0218] Here, a degradation equilibrium state indicates that the degradation state of each cell in the battery pack can be considered uniform. A degradation imbalance state indicates that the degradation state of each cell in the battery pack can be considered non-uniform.

[0219] The embodiments of this disclosure described above are implemented not only by apparatus and methods, but also by programs that implement functions corresponding to the configurations of the embodiments of this disclosure, or by recording media in which such programs are recorded. Based on the above description of the embodiments of this disclosure, those skilled in the art to which this disclosure pertains can readily implement this implementation.

[0220] Although the present disclosure has been described above with reference to limited embodiments and accompanying drawings, the present disclosure is not limited thereto, and it will be apparent to those skilled in the art that various modifications and variations may be made within the scope of the technical concept of the present disclosure and within the equivalent scope of the patent claims described below.

[0221] Furthermore, the above-described disclosure allows for various substitutions, modifications, and alterations by those skilled in the art within the scope of the technical concept of this disclosure. Therefore, this disclosure is not limited to the foregoing embodiments and drawings, but can be selectively combined and configured in whole or in part, allowing for various modifications.

[0222] [List of reference numerals]

[0223] 1: Vehicle

[0224] 10: Battery Pack

[0225] 11: Battery

[0226] 12: Measurement Unit

[0227] 100: Battery Management Unit

[0228] 110: Sectioning unit

[0229] 120: Diagnostic Unit

[0230] 130: Storage unit

Claims

1. A battery management device, comprising: A profile acquisition unit is configured to acquire 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 ratio based on each of a plurality of first profiles, calculate each target value as a diagnostic factor based on the calculated plurality of target ratios, generate a distribution profile indicating 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.

2. The battery management device according to claim 1, wherein, The first cross-section is the negative electrode cross-section, and The target ratio is the negative electrode change rate, which is the rate of change of the first profile compared to a preset reference negative electrode profile.

3. The battery management device according to claim 1, wherein, 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.

4. The battery management device according to claim 1, wherein, 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.

5. The battery management device according to claim 4, wherein, 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.

6. The battery management device according to claim 4, wherein, The diagnostic unit is configured to set the threshold based on the degree of degradation of the battery pack and a preset reference characteristic value.

7. The battery management device according to claim 1, wherein, 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.

8. The battery management device according to claim 7, wherein, The diagnostic unit is configured to determine a minimum value, a maximum value, and a reference value among 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.

9. The battery management device according to claim 8, wherein, 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.

10. The battery management device according to claim 7, wherein, The diagnostic unit is configured to compare the ratio with a preset critical ratio range and determine, based on the comparison result, whether the distribution profile meets the predetermined conditions.

11. The battery management device according to claim 10, wherein, The diagnostic unit is configured as follows: When the ratio falls within the critical ratio range, it is determined that the distribution profile satisfies the predetermined condition, and When the ratio does not fall within the critical ratio range, the distribution profile is determined to satisfy the predetermined condition.

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

13. The battery management device according to claim 1, wherein, The diagnostic unit is configured to calculate the negative electrode loss rate based on the ratio between a preset reference ratio of each of the plurality of batteries and the target ratio, and to determine the calculated negative electrode loss rate as the target value.

14. The battery management device according to claim 1, wherein, When the state of the battery pack is diagnosed as a deteriorated or unbalanced state, the diagnostic unit operates a function to resolve the deterioration or unbalance or outputs an alarm.

15. The battery management device according to claim 14, wherein, The function used to resolve the aforementioned deterioration imbalance is the group balancing function.

16. A battery pack comprising a battery management device according to any one of claims 1 to 15.

17. A vehicle comprising a battery management device according to any one of claims 1 to 15.

18. A battery management method, comprising: The profile acquisition step is to acquire a first profile of each of the multiple batteries included in the battery pack. The target value calculation step calculates a target ratio based on each of the plurality of first profiles, and calculates each target value as a diagnostic factor based on the calculated plurality of target ratios. A profile generation step, wherein the profile generation step generates a distribution profile that indicates 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 status diagnosis step, wherein the status diagnosis step diagnoses the status of the battery pack based on the determination result.

19. The battery management method according to claim 18, further comprising: The countermeasures step operates a function to resolve the deterioration imbalance or outputs an alarm when the state of the battery pack is diagnosed as a deterioration imbalance state in the state diagnosis step.

20. A non-transitory readable storage medium storing a program for performing a battery management method, the battery management method comprising: The profile acquisition step is to acquire a first profile of each of the multiple batteries included in the battery pack. The target value calculation step calculates a target ratio based on each of the plurality of first profiles, and calculates each target value as a diagnostic factor based on the calculated plurality of target ratios. A profile generation step, wherein the profile generation step generates a distribution profile that indicates 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 status diagnosis step, wherein the status diagnosis step diagnoses the status of the battery pack based on the determination result.

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