Battery diagnostic device, battery pack, electric vehicle, and battery diagnostic method

Abstract

A battery diagnostic device, a battery pack, an electric vehicle, and a battery diagnostic method are provided. The battery diagnostic device according to the present invention is provided for a battery array including a first battery to an mth battery (m is a natural number equal to or greater than 3) connected in series. The battery diagnostic device includes a sensing unit that detects the voltage of each of the first battery to the mth battery, and a control unit that generates a first voltage profile to an mth voltage profile that indicate a voltage change history of each of the first battery to the mth battery during charging or discharging of the battery array. The control unit diagnoses the battery array by comparing a reference voltage profile, which is any one of the first voltage profile to the mth voltage profile, with a first comparison voltage profile to an (m-1)th comparison voltage profile that are the remaining (m-1) voltage profiles other than the reference voltage profile.

Description

[Technical field]

[0001] The present invention relates to battery diagnosis, and more particularly to a technique for diagnosing abnormalities in multiple batteries connected in series.

[0002] This application claims priority to Korean Patent Application No. 10-2022-0111696 filed on September 2, 2022 and Korean Patent Application No. 10-2023-0103523 filed on August 8, 2023, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings. [Background technology]

[0003] In recent years, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has grown rapidly and the development of electric vehicles, energy storage batteries, robots, and artificial satellites has progressed in earnest, research into high-performance batteries that can be repeatedly charged and discharged is being actively conducted.

[0004] Currently commercially available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium batteries. Among them, lithium batteries are attracting attention due to their advantages of being able to be freely charged and discharged since they have almost no memory effect compared to nickel-based batteries, as well as their extremely low self-discharge rate and high energy density.

[0005] Although various researches are being conducted to increase the capacity and density of such batteries, it is also important to improve the life and safety of the batteries. To achieve this, it is necessary to suppress the decomposition reaction with the electrolyte on the surface of the electrodes, and to prevent overcharging and over-discharging.

[0006] In particular, during charging or discharging of a battery array including a plurality of batteries connected in series, an equal current flows through all the batteries, making it difficult to diagnose the state of each battery. Therefore, there is a need to develop a technology for diagnosing anomalies in each battery by analyzing the voltage behavior of each of the plurality of batteries during charging or discharging. Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made to solve the above problems, and an object of the present invention is to provide a battery diagnostic device and a battery diagnostic method that can quickly and accurately detect abnormalities in individual batteries through relative comparison of multiple voltage profiles obtained for multiple batteries.

[0008] Other objects and advantages of the present invention will become apparent from the following description and the embodiments of the present invention, and the objects and advantages of the present invention can be realized by the means and combinations thereof as set forth in the claims. [Means for solving the problem]

[0009] A battery diagnostic device according to one aspect of the present invention is provided for a battery array including a first battery to an mth battery (m is a natural number equal to or greater than 3) connected in series. The battery diagnostic device includes a sensing unit configured to detect the voltages of the first battery to the mth battery, and a control unit configured to generate a first voltage profile to an mth voltage profile indicating a voltage change history of the first battery to the mth battery, based on voltage measurement data collected from the sensing unit during charging or discharging of the battery array. The control unit is configured to diagnose the battery array by comparing a reference voltage profile, which is one voltage profile among the first voltage profile to the mth voltage profile, with a first comparison voltage profile to an (m-1)th comparison voltage profile, which are the remaining (m-1) voltage profiles other than the reference voltage profile.

[0010] The control unit may be configured to adjust the first comparison voltage profile through the (m-1)th comparison voltage profile, respectively, so as to minimize an amount of error from the reference voltage profile, to generate a first adjusted comparison voltage profile through a (m-1)th adjusted comparison voltage profile. The control unit may be configured to generate first main adjustment information through (m-1)th main adjustment information indicating adjustment levels from the first comparison voltage profile through the (m-1)th comparison voltage profile to the first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile, and to diagnose the battery array based on the first main adjustment information through the (m-1)th main adjustment information.

[0011] The control unit may be configured to determine the sum of squares or the root mean square error of the difference between the voltage of a j-th adjusted comparison voltage profile (j is a natural number less than m) among the first adjusted comparison voltage profile to the (m-1)th adjusted comparison voltage profile and the voltage of the reference voltage profile as the amount of error between the j-th comparison voltage profile and the reference voltage profile.

[0012] The control unit may be configured to determine a j-th voltage shift factor from the j-th comparison voltage profile to the j-th adjusted comparison voltage profile. The j-th main adjustment information among the first main adjustment information to the (m-1)-th main adjustment information includes the j-th voltage shift factor.

[0013] The control unit may be configured to diagnose an abnormality in each of the first battery to the mth battery or the battery array based on a distribution of the first voltage shift factor to the (m-1)th voltage shift factor of the first main adjustment information to the (m-1)th main adjustment information.

[0014] The control unit may be configured to determine a j-th voltage scale factor from the j-th comparison voltage profile to the j-th adjusted comparison voltage profile. The j-th main adjustment information among the first main adjustment information to the (m-1)th main adjustment information may include the j-th voltage scale factor.

[0015] The control unit may be configured to diagnose an abnormality in each of the first battery to the mth battery or the battery array based on a distribution of the first voltage scale factor to the (m-1)th voltage scale factor of the first main adjustment information to the (m-1)th main adjustment information.

[0016] The control unit may be configured to generate a reference differential voltage profile from the reference voltage profile. The control unit may be configured to generate a first comparative differential voltage profile through a (m-1)th comparative differential voltage profile from the first comparative voltage profile through the (m-1)th comparative voltage profile. The control unit may be configured to adjust the first comparative differential voltage profile through the (m-1)th comparative differential voltage profile, respectively, so that an error amount from the reference differential voltage profile is minimized, to generate a first adjusted comparative differential voltage profile through a (m-1)th adjusted comparative differential voltage profile. The control unit may be configured to generate first sub-adjustment information through (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential voltage profile through the (m-1)th comparative differential voltage profile to the first adjusted comparative differential voltage profile through the (m-1)th adjusted comparative differential voltage profile, and to diagnose an abnormality in each of the first battery through the mth battery or the battery array based further on the first sub-adjustment information through the (m-1)th sub-adjustment information.

[0017] The control unit may be configured to determine a j-th differential voltage shift factor from the j-th comparative differential voltage profile to the j-th adjusted comparative differential voltage profile. The j-th sub adjustment information among the first sub adjustment information to the (m-1)-th sub adjustment information may include the j-th differential voltage shift factor.

[0018] The control unit may be configured to determine a j-th differential voltage scale factor from the j-th comparative differential voltage profile to the j-th adjusted comparative differential voltage profile. The j-th sub adjustment information among the first sub adjustment information to the (m-1)-th sub adjustment information may include the j-th differential voltage scale factor.

[0019] A battery pack according to another aspect of the present invention includes the battery diagnostic device.

[0020] An electric vehicle according to yet another aspect of the present invention includes the battery pack.

[0021] A battery diagnostic method according to yet another aspect of the present invention is provided for a battery array including a first battery to an mth battery (m is a natural number equal to or greater than 3) connected in series. The battery diagnostic method includes the steps of: collecting voltage measurement data indicating the voltages of the first battery to the mth battery while charging or discharging the battery array; generating first to mth voltage profiles indicating a change history of the voltages of the first to mth batteries based on the voltage measurement data; and diagnosing the battery array by comparing a reference voltage profile, which is one voltage profile among the first to mth voltage profiles, with a first comparison voltage profile to an (m-1)th comparison voltage profile, which are the remaining (m-1) voltage profiles other than the reference voltage profile.

[0022] The step of diagnosing the battery array may include a step of adjusting the first comparison voltage profile through the (m-1)th comparison voltage profile, respectively, to generate a first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile so that an amount of error from the reference voltage profile is minimized, a step of generating first main adjustment information through the (m-1)th main adjustment information indicating adjustment levels from the first comparison voltage profile through the (m-1)th comparison voltage profile to the first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile, and a step of diagnosing an abnormality in each of the first battery through the mth battery or the battery array based on the first main adjustment information through the (m-1)th main adjustment information.

[0023] The battery diagnosis method may further include the steps of generating a reference differential voltage profile from the reference voltage profile; generating a first comparative differential voltage profile through the (m-1)th comparative differential voltage profile from the first comparative voltage profile through the (m-1)th comparative differential voltage profile; adjusting the first comparative differential voltage profile through the (m-1)th comparative differential voltage profile, respectively, so that an amount of error from the reference differential voltage profile is minimized to generate a first adjusted comparative differential voltage profile through the (m-1)th adjusted comparative differential voltage profile; and generating first sub-adjustment information through the (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential voltage profile through the (m-1)th comparative differential voltage profile to the first adjusted comparative differential voltage profile through the (m-1)th adjusted comparative differential voltage profile.

[0024] The step of diagnosing the battery array may further include diagnosing the battery array based on the first sub-adjustment information to the (m-1)th sub-adjustment information. Effect of the Invention

[0025] According to one aspect of the present invention, an abnormality in each battery can be detected by analyzing adjustment information of an adjustment process in which each voltage profile is adjusted so that an error amount between one of a plurality of voltage profiles that are one-to-one associated with a plurality of batteries connected in series is minimized. In other words, since an abnormality can be detected by analyzing a history of changes in the voltage of each of the plurality of batteries, the speed of abnormality detection is improved compared to other diagnosis methods that require additional parameters such as battery temperature.

[0026] In addition, according to one aspect of the present invention, one voltage profile among a plurality of voltage profiles is used as a reference and an error amount between each of the remaining voltage profiles is calculated to diagnose an abnormality in each battery. This has the advantage that abnormality detection is possible without having to secure reference data for abnormality detection in advance, and a large-capacity memory is not required.

[0027] The effects of the present invention are not limited to the effects described above, and other effects of the present invention not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0028] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited only to the matters described in the drawings. [Brief description of the drawings]

[0029] [Figure 1] 1 is a diagram illustrating a battery diagnostic device according to an embodiment of the present invention; [Diagram 2] 2 is a diagram illustrating a schematic diagram of a coupling relationship between a battery and a measuring unit illustrated in FIG. 1; [Diagram 3] 11 is a graph referenced in a description of adjustment operations that can be performed to generate an adjusted comparison voltage profile from a comparison voltage profile. [Figure 4] 11 is a graph referenced in a description of adjustment operations that can be performed to generate an adjusted comparison voltage profile from a comparison voltage profile. [Diagram 5] 11 is a graph referenced in a description of adjustment operations that can be performed to generate an adjusted comparison voltage profile from a comparison voltage profile. [Figure 6] 11 is a graph referenced in a description of adjustment operations that can be performed to generate an adjusted comparison voltage profile from a comparison voltage profile. [Figure 7] 11 is a graph referenced in a description of adjustment operations that can be performed to generate an adjusted comparison voltage profile from a comparison voltage profile. [Figure 8] FIG. 11 is a diagram referred to in explaining a process for calculating an amount of error between a reference voltage profile and an adjusted comparison voltage profile. [Figure 9] FIG. 13 is a diagram referenced in describing a differential voltage profile generated from a voltage profile. [Figure 10] FIG. 13 is a diagram referenced in the description of a differential capacitance profile generated from a voltage profile. [Figure 11] FIG. 2 illustrates an example distribution of voltage scale factors associated with a particular regulation operation of the regulation process. [Figure 12] FIG. 13 illustrates another example distribution of voltage scale factors associated with a particular regulation operation of the regulation process. [Figure 13] FIG. 13 illustrates yet another example distribution of voltage scale factors associated with a particular regulation operation of the regulation process. [Figure 14] FIG. 13 illustrates yet another example distribution of voltage scale factors associated with a particular regulation operation of the regulation process. [Figure 15] 1 is a diagram illustrating an exemplary battery pack according to an embodiment of the present invention. [Figure 16] FIG. 16 is an exemplary diagram illustrating an electric vehicle including the battery pack shown in FIG. 15. [Figure 17] FIG. 2 is a flow chart illustrating a battery diagnostic method according to an embodiment of the present invention. [Figure 18] FIG. 18 is a flow diagram showing an example of a sub-routine that may be included in step S1740 of FIG. [Figure 19] FIG. 18 is a flow diagram illustrating an example of a sub-routine that may be added to step S1740 of FIG. [Figure 20] FIG. 18 is a flow diagram illustrating another example of a sub-routine that may be added to step S1740 of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the present specification and claims should not be interpreted as being limited to their ordinary and dictionary meanings, but should be interpreted as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventor himself can appropriately define the concepts of terms in order to best describe the invention.

[0031] Therefore, it should be understood that the embodiment described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0032] Terms including ordinal numbers such as first, second, etc. are used to distinguish one of various components from other components, and are not intended to limit the components.

[0033] Throughout the specification, when a part "includes" a certain component, this does not mean to exclude other components, but means that other components may be further included, unless otherwise specified. Furthermore, terms such as "controller" described in the specification refer to a unit that processes at least one function or operation, and may be embodied in hardware, software, or a combination of hardware and software.

[0034] Furthermore, throughout this specification, when a part is referred to as being "connected" to another part, this includes not only a "direct connection" but also an "indirect connection" through other elements.

[0035] FIG. 1 is a diagram illustrating a battery diagnostic device according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating a connection relationship between a battery and a measuring unit shown in FIG.

[0036] 1 and 2, a battery diagnostic device 100 includes a measurement unit 110 and a control unit 120, and may further include a memory 130, optionally.

[0037] The battery diagnostic device 100 is provided to detect an abnormality in the battery array 20 or in each of the first battery B1 to the m-th battery Bm included therein, where m is a natural number of 3 or more.

[0038] The first battery B1 to the m-th battery Bm are electrically connected in series within the battery array 20. The battery array 20 may be included in a battery pack (reference numeral 10 in FIG. 15). In the following description common to the first battery B1 to the m-th battery Bm, the symbol B will be used to indicate a battery (cell group).

[0039] Battery B may include at least one battery cell. A battery cell refers to an energy storage element that has a negative terminal and a positive terminal and can be repeatedly charged and discharged independently. As an example, the battery cell may be a lithium ion cell or a lithium polymer cell. When Battery B includes multiple battery cells, Battery B may be referred to as a "cell group." At least two battery cells of the multiple battery cells of Cell Group B may be connected in parallel.

[0040] The measurement unit 110 may be configured to measure the voltage of each of the first battery B1 to the m-th battery Bm. The voltage measurement by the measurement unit 110 may be performed periodically at a predetermined sampling rate (e.g., 60 times / second). The measurement unit 110 may provide the control unit 120 with voltage measurement data including the measurement value of each of the voltages of the first battery B1 to the m-th battery Bm.

[0041] The measurement unit 110 may include a first voltage sensor to an m-th voltage sensor. If i is a natural number less than or equal to m, the ith voltage sensor may generate a sensing signal indicating a voltage value of a voltage applied across the ith battery Bi. The control unit 120 may collect the sensing signal (voltage measurement data) from the ith voltage sensor and monitor the voltage of the ith battery Bi in real time.

[0042] The measurement unit 110 may include a current sensor (reference symbol CS in FIG. 15). The current sensor CS may include a known current detection element such as a shunt resistor and / or a Hall sensor, for example. The current sensor CS may generate a sensing signal (current measurement data) indicating a current value (i.e., a magnitude and a direction of a current) of a current flowing through the battery array 20. The control unit 120 may periodically collect the current measurement data from the current sensor CS and calculate an accumulated capacity (current integration value) from a specific point in time based on the current measurement data.

[0043] The measurement unit 110 may include at least one temperature sensor TS. When the measurement unit 110 includes only one temperature sensor TS, the temperature measured by the temperature sensor TS may be treated as a representative temperature (e.g., an average temperature) of the first battery B1 to the m-th battery Bm.

[0044] Alternatively, the measurement unit 110 may include m temperature sensors TS, in which case the m temperature sensors TS may be configured to measure the temperatures of the first battery B1 through the m-th battery Bm, respectively. The control unit 120 may collect sensing signals from the m temperature sensors TS and monitor the temperatures of the first battery B1 through the m-th battery Bm in real time.

[0045] As the temperature sensor TS, any temperature detection means known in the art, such as a thermocouple, can be used.

[0046] 2, the first voltage sensor VS1 through the mth voltage sensor VSm are connected in parallel to the first battery B1 through the mth battery Bm in a one-to-one relationship. That is, a pair of measurement terminals of the ith voltage sensor VSi are connected to the positive and negative terminals of the ith battery Bi, respectively.

[0047] Specifically, the first voltage sensor VS1 may be configured to measure a voltage across the first battery B1 during charging or discharging of the first battery B1. The second voltage sensor VS2 may be configured to measure a voltage across the second battery B2 during charging or discharging of the second battery B2. The mth voltage sensor VSm may be configured to measure a voltage across the mth battery Bm during charging or discharging.

[0048] Here, since the first battery B1 through the m-th battery Bm are electrically connected in series with each other, an equal charging or discharging current flows through the first battery B1 through the m-th battery Bm during charging or discharging of the first battery B1 through the m-th battery Bm. For example, under the control of the control unit 120, the first battery B1 through the m-th battery Bm may be charged or discharged at a constant current of a predetermined current rate.

[0049] The control unit 120 may generate a first voltage profile to an m-th voltage profile indicating a change history of the voltage of each of the first battery B1 to the m-th battery Bm during charging or discharging of the battery pack 10. Each voltage profile is a type of voltage time series indicating a change in voltage according to time or capacity, and can be said to be a relationship curve between time and voltage or a relationship curve between capacity and voltage. For convenience of explanation, it is assumed below that each voltage profile indicates a change in voltage according to capacity.

[0050] As described above, an equal current flows through the first battery B1 to the m-th battery Bm during charging or discharging of the battery pack 10. Therefore, the control unit 120 can monitor a capacity change during charging or discharging of the battery pack 10 through ampere counting, which periodically integrates a current value collected from the current sensor CS.

[0051] The control unit 120 may generate an ith voltage profile based on the capacity and voltage of the ith battery Bi while the first battery B1 through the mth battery Bm are charged or discharged by a constant or non-constant current. That is, the control unit 120 may generate the ith voltage profile by repeating an operation of mapping the capacity (or measurement time point) and voltage monitored for each timing for the ith battery Bi to each other and recording the mapping in memory. As a result, the first voltage profile through the mth voltage profile that are one-to-one associated with the first battery B1 through the mth battery Bm are generated. The battery diagnosis process that utilizes the voltage profiles will be described in more detail below.

[0052] The memory 130 may store data and programs necessary for each component of the battery diagnostic device 100 to operate and function. The memory 130 may also store data collected and generated during the operation and function of the measurement unit 110 and the control unit 120. The memory 130 may be provided inside or outside the control unit 120 and may be operably connected to the control unit 120 by various well-known means such as a data bus. The memory 130 may store at least one program, application, data, or instruction executed by the control unit 120.

[0053] The memory 130 is not particularly limited in type as long as it is a known information recording means known to be capable of recording, erasing, updating, and reading data. The memory may be embodied in at least one form of a flash memory, a hard disk, a solid state disk (SSD), a solid disk drive (SDD), a multimedia micro card, a random access memory (RAM), a static RAM (SRAM), a read only memory (ROM), an electrically erasable programmable ROM (EEPROM), and a programmable ROM (PROM), but the present invention is not limited to such a specific form of memory. The memory 130 may also store program code that defines processes executable by the control unit 120.

[0054] Battery identification numbers previously assigned to the first battery B1 through the m-th battery Bm may be recorded in the memory 130. The control unit 120 may map the identification number of the ith battery Bi to data relating to the ith battery Bi and record the mapped identification number in the memory 130 during execution of the diagnosis process according to the present invention.

[0055] The control unit 120 may be configured to set one of the first voltage profile to the mth voltage profile as a reference voltage profile, and to set the remaining (m-1) voltage profiles as the first comparison voltage profile to the (m-1)th comparison voltage profile.

[0056] The reference voltage profile may be randomly selected from the first to m-th voltage profiles, or the control unit 120 may select, as the reference voltage profile, a voltage profile associated with one battery among the first to m-th batteries, whose voltage or SOC is closest to the average of the first to m-th batteries.

[0057] The reference voltage profile may be a voltage profile set as a reference for relative comparison with the full charge capacity (FCC) of the first battery B1 to the m-th battery Bm. Furthermore, the control unit 120 may select the remaining (m-1) voltage profiles, excluding the reference voltage profile, from among the first voltage profile to the m-th voltage profile, as the first comparison voltage profile to the (m-1)th comparison voltage profile to be subjected to an adjustment operation, which will be described later.

[0058] For example, when the voltage profile of the first battery B1 is selected as the reference voltage profile, the control unit 120 may set the second voltage profile to the mth voltage profile of the second battery B2 to the mth battery Bm as the first comparison voltage profile to the (m-1)th comparison voltage profile. Here, it will be easily understandable to those skilled in the art that the second voltage profile is set to the first comparison voltage profile and the mth voltage profile is set to the (m-1)th comparison voltage profile.

[0059] The control unit 120 compares the first comparison voltage profile to the (m-1)th comparison voltage profile with the reference voltage profile to diagnose an abnormality in the battery array 20 or the battery B.

[0060] In detail, the control unit 120 may adjust the first comparison voltage profile to the (m-1)th comparison voltage profile so as to correspond to the reference voltage profile, respectively, to generate the first adjusted comparison voltage profile to the (m-1)th adjusted comparison voltage profile. Corresponding to the reference voltage profile means that the amount of error from the reference voltage profile is minimized or falls within a predetermined allowable error range. Here, when j is a natural number less than m, the amount of error between the reference voltage profile and the jth adjusted comparison voltage profile may be the sum of squares, root mean square error (RMSE), or integral value of the difference between the voltage of the jth adjusted comparison voltage profile and the voltage of the reference voltage profile over a specific capacity range, or may be the integral value of the absolute value of the voltage difference.

[0061] The j-th adjusted comparison voltage profile is one of a plurality of adjusted comparison voltage profiles obtained by adjusting the j-th comparison voltage profile to several levels. The control unit 120 may calculate a root mean square error (RMSE) between each of the plurality of adjusted comparison voltage profiles obtained from the j-th comparison voltage profile and a reference voltage profile, and identify one of the plurality of adjusted comparison voltage profiles with the smallest RMSE as the j-th adjusted comparison voltage profile. The adjustment operation performed by the control unit 120 on each comparison voltage profile to correspond to the reference voltage profile will be described in more detail below with reference to FIGS. 3 to 7.

[0062] The control unit 120 may generate first main adjustment information through (m-1)th main adjustment information indicating adjustment levels from the first comparative voltage profile through the (m-1)th comparative voltage profile to the first adjusted comparative voltage profile through the (m-1)th adjusted comparative voltage profile. The jth main adjustment information may be a data set defining how and to what extent the jth comparative voltage profile was adjusted to generate the jth adjusted comparative voltage profile.

[0063] The adjustment process from the first comparison voltage profile through the (m-1)th comparison voltage profile to the first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile essentially includes a first adjustment operation (Y-axis shift), and may further include at least one of a second adjustment operation (Y-axis scale), a third adjustment operation (X-axis shift), and a fourth adjustment operation (X-axis scale).

[0064] The first adjustment operation (Y-axis shift) may be an operation of moving the jth comparison voltage profile along the Y-axis (voltage) as a whole. The adjustment amount by the first adjustment operation may be referred to as a voltage shift amount (or voltage shift factor). As an example, a voltage shift factor of +0.1V means that the jth adjusted comparison voltage profile is generally located 0.1V above (at a higher voltage) than the jth comparison voltage profile.

[0065] The second adjustment operation (Y-axis scale) may be an operation of shrinking or expanding the jth comparison voltage profile along the Y-axis. The adjustment amount by the second adjustment operation may be referred to as a voltage scale amount (or voltage scale factor). As an example, a voltage scale factor of 101% means that the voltage range of the jth adjusted comparison voltage profile is 1.01 times that of the jth comparison voltage profile, and a voltage shift factor of 98% means that the voltage range of the jth adjusted comparison voltage profile is 0.98 times that of the jth comparison voltage profile.

[0066] The third adjustment operation (X-axis shift) may be an operation of generally shifting the jth comparison voltage profile along the X-axis (capacity). The adjustment amount by the third adjustment operation may be referred to as a capacity shift amount (or a capacity shift factor). As an example, a capacity shift factor of -2.2 Ah means that the jth adjusted comparison voltage profile is generally located 2.2 Ah to the left (lower capacity) than the jth comparison voltage profile.

[0067] The fourth adjustment operation (X-axis scale) may be an operation of shrinking or expanding the jth comparison voltage profile along the X-axis. The adjustment amount by the fourth adjustment operation may be referred to as a capacitance scale amount (or capacitance scale factor). As an example, a capacitance scale factor of 103% means that the capacitance range of the jth adjusted comparison voltage profile is 1.03 times that of the jth comparison voltage profile.

[0068] The jth main adjustment information includes an adjustment amount by the first adjustment operation, and may further include at least one of the adjustment amounts by the second to fourth adjustment operations. In addition, since no adjustment operation is performed on the reference voltage profile, the adjustment amounts of the first to fourth adjustment operations related to the reference voltage profile may be defaulted to 0V, 100%, 0Ah, and 100%, respectively. For reference, other units besides V, Ah, and % may be used as the unit of the adjustment amount.

[0069] The control unit 120 may be configured to identify an abnormality in each of the first battery B1 to the m-th battery Bm or an abnormality in the battery array 20, based on the first main adjustment information to the (m-1)th main adjustment information.

[0070] The control unit 120 may identify that if the X-axis length (i.e., capacity range) of the jth adjusted comparison voltage profile is relatively longer than the X-axis length of the jth comparison voltage profile (e.g., magnification, capacity scale factor is greater than 100%), the full charge capacity of the battery associated with the jth comparison voltage profile is less than the full charge capacity of the reference battery by an amount corresponding to the adjustment information.

[0071] The control unit 120 may identify that if the X-axis length (i.e., capacity range) of the jth adjusted comparison voltage profile is relatively shorter than the X-axis length of the jth comparison voltage profile (e.g., scaled down, capacity scale factor is less than 100%), the full charge capacity of the battery associated with the jth comparison voltage profile is greater than the full charge capacity of the reference battery by an amount corresponding to the adjustment information.

[0072] For example, when the full charge capacity of the reference battery is 100 Ah, if the jth main adjustment information is 103%, the control unit 120 may determine that the full charge capacity of the battery associated with the jth comparison voltage profile is 3%p smaller than the full charge capacity of the reference battery.

[0073] The control unit 120 may analyze the distribution of adjustment amounts of the same type in the first main adjustment information to the (m-1)th main adjustment information, and diagnose an abnormality in each of the first battery B1 to the m-th battery Bm or an abnormality in the battery array 20. That is, the control unit 120 may determine an abnormality in each of the first battery B1 to the m-th battery Bm based on at least one of the distribution of adjustment amounts due to the first adjustment operation, the distribution of adjustment amounts due to the second adjustment operation, the distribution of adjustment amounts due to the third adjustment operation, and the distribution of adjustment amounts due to the fourth adjustment operation.

[0074] The control unit 120 may be configured to determine that, among the first battery B1 to the m-th battery Bm, a battery associated with an adjustment amount that falls within a reference range for each adjustment operation is normal, and determine that a battery other than that is abnormal.

[0075] When the adjustment amounts of the first battery B1 to the m-th battery Bm are all within the reference range, the control unit 120 can determine that the first battery B1 to the m-th battery Bm are all normal.

[0076] The control unit 120 may determine that the battery array 20 is normal if the number of adjustment amounts that fall outside the reference range among the adjustment amounts of the first battery B1 to the mth battery Bm is less than a critical value, and may determine that the battery array 20 is abnormal otherwise.

[0077] Battery B being normal means that the voltage and capacity characteristics of battery B have an acceptable level of difference compared to the other batteries in the battery array 20.

[0078] The battery diagnostic device 100 can easily check the state of each of the first battery B1 to the m-th battery Bm by using the first main adjustment information to the (m-1)th main adjustment information.

[0079] Even when the first battery B1 through the mth battery Bm connected in series are charged or discharged with current of the same magnitude and in the same direction, the actual capacity change of each battery may differ from the capacity change (accumulated current value) due to ampere counting, depending on the electrochemical characteristics of each battery or the impedance of the charger / discharger.

[0080] The battery diagnostic device 100 can identify a relative abnormality level for each of the remaining batteries, the first battery B1 through the m-th battery Bm, based on the first main adjustment information through the (m-1)th main adjustment information generated as a result of adjusting the first comparison voltage profile through the (m-1)th comparison voltage profile based on the reference voltage profile. Therefore, the battery diagnostic device 100 according to an embodiment can easily diagnose the state of the battery B without having to previously record reference data based on temperature, etc. in the memory 130, and therefore has an advantage that the memory 130 does not require a large capacity storage area.

[0081] As described above, the battery diagnostic device 100 performs battery abnormality diagnosis using only a single parameter, that is, the voltage behavior, regardless of the temperature of the battery B, thereby improving the speed of the abnormality diagnosis.

[0082] The control unit 120 may be operatively coupled to other components of the battery diagnostic apparatus 100 and may control various operations of the battery diagnostic apparatus 100. The control unit 120 may perform various operations of the battery diagnostic apparatus 100 by executing one or more instructions stored in the memory 130.

[0083] The control unit 120 may be referred to as a "control circuit" or a "battery controller" and may be implemented in hardware using at least one of application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), microprocessors, and other electrical units for performing functions. When the control logic is implemented as software, the control unit 120 may be implemented as a collection of program modules. In this case, the program modules may be stored in the memory 130 and executed by the control unit 120.

[0084] In particular, when the battery diagnostic device 100 according to the present invention is included in the battery pack 10, the battery pack 10 may include a control device referred to by terms such as MCU (Micro Controller Unit) or BMS (Battery Management System). In this case, the control unit 120 may also be embodied by a component such as MCU or BMS provided in the battery pack 10. Also, in this specification, the terms "perform" or "configured to perform" with respect to an operation or function of the control unit 120 may include the meaning of "programmed to perform".

[0085] 3-7 are graphs referenced in describing adjustment operations that can be performed to generate an adjusted comparison voltage profile from a comparison voltage profile. In each of the graphs shown in FIG. 3-7, the X-axis represents capacity (Ah) and the Y-axis represents voltage (V).

[0086] Referring to FIG. 3, a reference voltage profile R and a comparison voltage profile T are shown. The comparison voltage profile T is any one of the first comparison voltage profile to the (m-1)th comparison voltage profile. For example, the reference voltage profile R may be the voltage profile of the second battery B2, and the comparison voltage profile T may be the voltage profile of the first battery B1. For convenience of explanation, each voltage profile is assumed to indicate the relationship between the capacity and voltage of the battery when the battery array 20 is being charged. Note that the X-axis does not indicate the remaining capacity of the battery, but indicates the current integration value from a specific point in time (for example, the point in time when a diagnosis-requiring event occurs).

[0087] Since two batteries (eg, B1, B2) are connected in series, the capacity ranges of the reference voltage profile R and the comparison voltage profile T (illustrated as 0 to 100 Ah in FIG. 3) are the same.

[0088] 3, it can be seen that the voltage (Vra) at the start point (RA) of the reference voltage profile R is different from the voltage (Vta) at the start point (TA) of the comparison voltage profile T. In addition, the voltage (Vrb) at the end point (RB) of the reference voltage profile R is also different from the voltage (Vtb) at the end point (TB) of the comparison voltage profile T. Such a difference between the two voltage profiles (R, T) is due to differences in characteristics such as the degree of deterioration (full charge capacity) and internal resistance of the two batteries (e.g., B1, B2).

[0089] In particular, FIG. 3 illustrates a case where the voltage increase rate of the comparison voltage profile T is greater than that of the reference voltage profile R in the same capacity range (0-100 Ah). This can also be confirmed by the fact that the voltage difference (ΔVe=Vtb-Vrb) at the end point 100 Ah of the capacity range is greater than the voltage difference (ΔVs=Vta-Vra) at the start point 0 Ah of the capacity range. For reference, if the reference voltage profile R is the voltage profile of battery B2 and the comparison voltage profile T is the voltage profile of battery B1, it can be seen from the comparison of the two voltage profiles (R, T) that battery B1 has a higher internal resistance or a lower full charge capacity than battery B2. In other words, there is a higher possibility that battery B1 is abnormal compared to battery B2.

[0090] FIG. 4 is a diagram referred to for an exemplary explanation of the first adjustment operation for the comparison voltage profile T shown in FIG.

[0091] Since the comparison voltage profile T is located above the reference voltage profile R throughout the entire capacitance range, shifting the comparison voltage profile T downward toward the reference voltage profile R should reduce the amount of error between the comparison voltage profile T and the reference voltage profile R.

[0092] The control unit 120 may perform a first adjustment operation to shift the comparison voltage profile T in the Y-axis direction while keeping the reference voltage profile R fixed. Referring to Fig. 4, the adjusted comparison voltage profile T1 is the result of moving the comparison voltage profile T in the Y-axis direction by ΔV.

[0093] The control unit 120 can determine the adjustment amount (i.e., voltage shift factor) of the first adjustment operation that minimizes the amount of error by shifting the comparison voltage profile T by a small amount (e.g., 0.001 V) in the Y-axis direction and then repeating the first adjustment operation that monitors the amount of error from the reference voltage profile R.

[0094] FIG. 5 is a diagram referred to for an exemplary explanation of the second adjustment operation for the comparison voltage profile T shown in FIG.

[0095] The control unit 120 may execute a second adjustment operation to scale (contract or expand) the comparison voltage profile T in the Y-axis direction.

[0096] Since the voltage range (Vta to Vtb) of the comparison voltage profile T is larger than the voltage range (Vra to Vrb) of the reference voltage profile R, by shrinking (compressing) the comparison voltage profile T in the Y-axis direction, the amount of error between the comparison voltage profile T and the reference voltage profile R should decrease.

[0097] The control unit 120 can determine the adjustment amount (i.e., voltage scale factor) of the second adjustment operation that minimizes the amount of error by reducing the comparison voltage profile T by a small ratio (e.g., 0.01%) along the Y axis and then repeating the second adjustment operation in which the amount of error from the reference voltage profile R is monitored.

[0098] 5, the adjusted comparison voltage profile T2 is the result of scaling the comparison voltage profile T so that the other parts shrink along the Y axis while keeping the starting point (TA) of the comparison voltage profile T fixed. As an example, a voltage scale factor of 99% means that the magnitude of the voltage range of the adjusted comparison voltage profile T2 (Vtb2-Vta) is 99% of the magnitude of the voltage range of the comparison voltage profile T (Vtb-Vta). In addition, if the voltage of the comparison voltage profile T at a specific capacity (Qk) is Vq and the voltage of the adjusted comparison voltage profile T2 is Vq2, then Vq2 is "Vta+(Vq-Vta)×0.99[V]".

[0099] FIG. 6 is a diagram referred to for an exemplary explanation of the third adjusting operation for the comparison voltage profile T shown in FIG.

[0100] In FIG. 3 described above, as the capacitance increases along the X-axis, the voltage difference between the reference voltage profile R and the comparison voltage profile T tends to increase, so by shifting the comparison voltage profile T to the right along the X-axis, the amount of error between the comparison voltage profile T and the reference voltage profile R should decrease.

[0101] The control unit 120 may perform a third adjustment operation to shift the comparison voltage profile T in the X-axis direction. Referring to FIG 6, the adjusted comparison voltage profile T3 is a result of shifting the comparison voltage profile T in the Y-axis direction by ΔQ. The voltages of the start point and the end point of the adjusted comparison voltage profile T3 are the same as those of the comparison voltage profile T.

[0102] The control unit 120 can determine the adjustment amount (i.e., capacity shift factor) of the third adjustment operation that minimizes the amount of error by shifting the comparison voltage profile T by a small amount (e.g., 0.01 Ah) in the X-axis direction and then repeating the third adjustment operation in which the amount of error from the reference voltage profile R is monitored.

[0103] FIG. 7 is a diagram referred to for an exemplary explanation of the fourth adjusting operation for the comparison voltage profile T shown in FIG.

[0104] The control unit 120 may execute a fourth adjustment operation of scaling (shrinking or expanding) the comparison voltage profile T in the X-axis direction.

[0105] Since the voltage slope of the comparison voltage profile T is steeper than the voltage slope of the reference voltage profile R, the amount of error between the comparison voltage profile T and the reference voltage profile R should be reduced by expanding the comparison voltage profile T in the X-axis direction.

[0106] The control unit 120 can repeat the fourth adjustment operation of scaling up the comparison voltage profile T by a small ratio (e.g., 0.01%) along the X-axis and then monitoring the amount of error with respect to the reference voltage profile R, thereby determining the adjustment amount (i.e., the capacitance scale factor) of the fourth adjustment operation that minimizes the amount of error.

[0107] As an example, a capacity scale factor of 110% means that the size of the capacity range of the adjusted comparison voltage profile T4 is 1.1 times the capacity range of the comparison voltage profile T. In Fig. 7, the adjusted comparison voltage profile T4 is the result of scaling such that the start point (TA) of the comparison voltage profile T is fixed and other parts are expanded by 1.1 times along the X-axis. In addition, if the capacity of the comparison voltage profile T at a specific voltage (Vu) is QT and the capacity of the adjusted comparison voltage profile T2 is QT4, then QT4 is "1.1 x QT [Ah]".

[0108] When determining the adjustment amount of the fourth adjusting operation, control unit 120 may be based on the error amount for the overlapping portion between the capacity range of reference voltage profile R and the capacity range of adjusted comparison voltage profile T4. For example, in Fig. 7, the capacity range of reference voltage profile R is 0 to 100 Ah, while the capacity range of adjusted comparison voltage profile T4 is 0 to 110 Ah, so the adjustment amount of the fourth adjusting operation is determined based on the error amount in the overlapping portion of the two ranges, 0 to 100 Ah.

[0109] The process of generating an adjusted comparison voltage profile corresponding to a comparison voltage profile by individually executing the first to fourth adjustment operations has been described above with reference to FIGS.

[0110] In this regard, only the first adjustment operation may be performed on the jth comparison voltage profile, or at least one of the second adjustment operation to the fourth adjustment operation may be further performed. When generating the jth adjusted comparison voltage profile from the jth comparison voltage profile, the order of performing two or more of the first adjustment operation to the fourth adjustment operation is not limited. For example, when combining the first adjustment operation and the second adjustment operation, the second adjustment operation may be performed after the first adjustment operation, or the reverse order may be used.

[0111] FIG. 8 is a diagram referred to in explaining the process of calculating the amount of error between the reference voltage profile and the adjusted comparison voltage profile.

[0112] In FIG. 8, profile TF illustrates an adjusted comparison voltage profile that has been identified through the adjustment process described above to have a minimal amount of error from reference voltage profile R.

[0113] Referring to FIG. 8 in conjunction with FIG. 3, the comparison voltage profile T and the adjusted comparison voltage profile TF are compared as follows.

[0114] First, the start point (TFA) of the profile TF is located below the start point (TA) of the profile T, which indicates that the adjustment amount (voltage shift factor) of the first adjustment operation is a negative value.

[0115] Second, if the difference between the voltage at the start point (TFA) and the voltage at the end point (TFB) of the profile TF is smaller than the difference between the voltage at the start point (TA) and the voltage at the end point (TB) of the profile T, it indicates that the adjustment amount (voltage scale factor) of the second adjustment operation is less than 100%.

[0116] Third, since the capacity at the start point (TFA) of profile TF and the capacity at the start point (TA) of profile T are equal to 0 Ah, it is understood that the adjustment amount (capacity shift factor) of the third adjusting operation is 0.

[0117] Fourth, the capacity range of profile TF is wider than the capacity range of profile T, which indicates that the adjustment amount (capacity scale factor) of the fourth adjustment operation is 100% or more.

[0118] The control unit 120 may set the volume range of interest to 0 to 100 Ah, which is common to the profile TF and the profile R. Thereafter, the control unit 120 may search for a mismatched portion (the shaded portion in FIG. 8) between the profile TF and the profile R in the volume range of interest, and determine an error amount (e.g., RMSE) of the profile TF with respect to the profile R.

[0119] The control unit 120 may calculate the length of the comparison voltage profile T and the length of the adjusted comparison voltage profile TF using various known methods. As an example, the control unit 120 may calculate the length of any profile using the following Equation 1.

[0120]

number

[0121] In Equation 1, L is the length of an arbitrary profile, f(x) is a function indicating an arbitrary profile (e.g., a comparison voltage profile, an adjusted comparison voltage profile), f'(x) is a derivative of f(x), and a and b are the lower and upper limits of a capacitance range for which the length is to be calculated.

[0122] The control unit 120 may use Equation 1 to calculate the lengths of the reference voltage profile R, the comparison voltage profile T, and the adjusted comparison voltage profile TF.

[0123] The control unit 120 may add the ratio of the length of the adjusted comparison voltage profile TF to the length of the comparison voltage profile T to the main adjustment information of the adjusted comparison voltage profile TF.

[0124] In the above-described manner, the control unit 120 may perform the adjustment operation for each of the first comparative voltage profile to the (m-1)th comparative voltage profile to calculate the first main adjustment information to the (m-1)th main adjustment information.

[0125] The control unit 120 acquires (m-1) factors related to at least one of the first adjustment operation to the fourth adjustment operation from the first main adjustment information to the (m-1)th main adjustment information, and can diagnose whether there is an abnormality in each of the first battery B1 to the mth battery Bm or whether there is an abnormality in the battery array 20 based on the distribution of the acquired (m-1) factors.

[0126] The control unit 120 may further utilize differential information of each of the reference voltage profile and the first to (m-1)th comparison voltage profiles when diagnosing the battery array 20. Hereinafter, two embodiments for acquiring differential information for each voltage profile will be described with reference to Figs. 9 and 10.

[0127] 9 is a diagram referred to in explaining a differential voltage profile generated from a voltage profile, in which the X-axis indicates capacitance and the Y-axis indicates differential voltage (dV / dQ).

[0128] The control unit 120 may generate an ith differential voltage profile from the ith voltage profile of the ith battery Bi. The ith differential voltage profile is a data set obtained from the ith voltage profile, and indicates the relationship between (i) the capacity and (ii) the differential voltage (dV / dQ) of the ith voltage profile. dV / dQ is the ratio of the change (dV) in voltage (V) to unit capacity (dQ). In other words, the differential voltage (dV / dQ) is the rate of change of voltage to capacity.

[0129] The control unit 120 may generate a reference differential voltage profile from the reference voltage profile, and may generate the first comparative differential voltage profile through the (m-1)th comparative differential voltage profile from the first comparative voltage profile through the (m-1)th comparative voltage profile.

[0130] 9 in conjunction with FIG. 3, profile RDV illustrates a reference differential voltage profile obtained from reference voltage profile R of FIG. 3, and profile TDV illustrates a comparison differential voltage profile obtained from comparison voltage profile T of FIG.

[0131] The control unit 120 can commonly apply an adjustment process including at least one of the first adjustment operation to the (m-1)th comparative differential voltage profile described above with reference to FIGS. 4 to 7 to the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile, thereby obtaining the first adjusted comparative differential voltage profile to the (m-1)th adjusted comparative differential voltage profile from the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile. That is, the voltage profile and the differential voltage profile differ only in that the units of the Y-axis are "voltage (V)" and "differential voltage (dV / dQ)". Therefore, by replacing only the units of the Y-axis in the above-described content for the first adjustment operation to the fourth adjustment operation, the first adjusted comparative differential voltage profile to the (m-1)th adjusted comparative differential voltage profile can be obtained from the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile.

[0132] The control unit 120 may generate first sub-adjustment information to (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile to the first adjusted comparative differential voltage profile to the (m-1)th adjusted comparative differential voltage profile. The jth sub-adjustment information may be a data set that defines how and to what extent the jth comparative differential voltage profile is adjusted to generate the jth adjusted comparative differential voltage profile. In this case, the adjustment amount of the first adjustment operation included in the jth sub-adjustment information may be referred to as a "differential voltage shift factor", and the adjustment amount of the second adjustment operation may be referred to as a "differential voltage scale factor". The sub-adjustment information obtained from the differential voltage profile may be referred to as "differential voltage curve-based adjustment information".

[0133] 10 is a diagram referred to in describing a differential capacitance profile generated from a voltage profile, in which the X-axis represents voltage and the Y-axis represents differential capacitance (dQ / dV).

[0134] The controller 120 may generate an ith differential capacity profile from the ith voltage profile. The ith differential capacity profile is a data set obtained from the ith voltage profile, and indicates the relationship between (i) voltage and (ii) differential capacity (dQ / dV) of the ith voltage profile. dQ / dV is the ratio of the change (dQ) in capacitance (Q) to unit voltage (dV). In other words, the differential capacity (dQ / dV) is the rate of change of capacitance with respect to voltage.

[0135] The control unit 120 may generate a reference differential capacitance profile from the reference voltage profile, and may generate first to (m-1)th comparative differential capacitance profiles from the first to (m-1)th comparative voltage profiles.

[0136] 10 in conjunction with FIG. 3, profile RDQ illustrates a reference differential capacitance profile obtained from reference voltage profile R of FIG. 3, and profile TDQ illustrates a comparison differential capacitance profile obtained from comparison voltage profile T of FIG.

[0137] The control unit 120 can commonly apply an adjustment process including at least one of the first adjustment operation to the (m-1)th comparative differential capacity profile described above with reference to FIGS. 4 to 7 to the first comparative differential capacity profile to the (m-1)th comparative differential capacity profile, thereby obtaining the first adjusted comparative differential capacity profile to the (m-1)th adjusted comparative differential capacity profile from the first comparative differential capacity profile to the (m-1)th comparative differential capacity profile. That is, the voltage profile and the differential capacity profile only differ in that the units of the X-axis are "capacity" and "voltage" and the units of the Y-axis are "voltage" and "differential capacity". Therefore, by replacing only the units of the X-axis and the Y-axis in the above-described content for the first adjustment operation to the fourth adjustment operation, the first adjusted comparative differential capacity profile to the (m-1)th adjusted comparative differential capacity profile can be obtained from the first comparative differential capacity profile to the (m-1)th comparative differential capacity profile.

[0138] The control unit 120 may generate first sub-adjustment information to (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential capacity profile to the (m-1)th comparative differential capacity profile to the first adjusted comparative differential capacity profile to the (m-1)th adjusted comparative differential capacity profile. The jth sub-adjustment information may be a data set that defines how and to what extent the jth comparative differential capacity profile was adjusted to generate the jth adjusted comparative differential capacity profile. The sub-adjustment information obtained from the differential capacity profile may be referred to as "differential capacity curve-based adjustment information."

[0139] The control unit 120 diagnoses whether there is an abnormality in each of the first battery to the mth battery or in the battery array 20 based on the first main adjustment information to the (m-1)th main adjustment information. Depending on the implementation, the control unit 120 may further use the first sub adjustment information to the (m-1)th sub adjustment information when diagnosing an abnormality in each of the first battery B1 to the mth battery Bm or in the battery array 20.

[0140] Hereinafter, an embodiment will be described in which the control unit 120 determines the battery state based on the calculated adjustment information and reference range. For convenience of explanation, in Fig. 11 to Fig. 14, a diagnosis method using the first voltage scale factor to the (m-1)th voltage scale factor, which are result values ​​of the second adjustment operation among the first adjustment operation to the fourth adjustment operation, will be described. In Fig. 11 to Fig. 14, the maximum value of the identification number is 100, that is, the battery array 20 includes a total of 100 batteries (B1 to B100).

[0141] The control unit 120 may determine a representative value of the first voltage scale factor through the (m-1)th voltage scale factor. The first voltage scale factor through the (m-1)th voltage scale factor are results of performing the above-described adjustment process on the first comparison voltage profile through the (m-1)th comparison voltage profile T, respectively, and are associated with the second adjustment operation. For example, the representative value may be an average value or a median value of the first voltage scale factor through the (m-1)th voltage scale factor.

[0142] The control unit 120 may calculate the standard deviation and average value as distribution information of the first to (m-1)th voltage scale factors, and set a reference range for diagnosing an abnormality in the battery B based on the standard deviation and average value.

[0143] Specifically, the control unit 120 may determine the reference range so that the median is equal to the representative value, the upper limit is greater than the representative value by a tolerance value, and the lower limit is smaller than the representative value by a tolerance value. Here, the tolerance value may be equal to the standard deviation or equal to a value obtained by multiplying the standard deviation by a predetermined positive coefficient.

[0144] The battery diagnostic device 100 has an advantage in that the possibility of misdiagnosis is reduced and the accuracy of abnormality diagnosis is improved since the reference range is set by utilizing the distribution information as described above.

[0145] 11 is a diagram illustrating an example of a distribution of voltage scale factors associated with a particular conditioning operation of the conditioning process, where the Y-axis represents the voltage scale factor value and the X-axis represents the battery identification number.

[0146] 11, the upper and lower limits of the reference range RR1 are 100.8% and 99.2%, respectively. From this, it can be seen that the average value of the first voltage scale factor to the (m-1)th voltage scale factor is (100.8+99.2) / 2=100.0%, and the tolerance is 0.8%. As mentioned above, 100.0% is also the voltage scale factor associated with the reference voltage profile.

[0147] Since the first voltage scale factor through the (m-1)th voltage scale factor are all within the reference range RR1, the control unit 120 may determine that the first battery B1 through the mth battery Bm are all normal. In addition, since the first battery B1 through the mth battery Bm are all determined to be normal, the control unit 120 may determine that the battery array 20 is also normal.

[0148] 12 is a diagram illustrating another example of a distribution of voltage scale factors associated with a particular conditioning operation of the conditioning process, where the Y-axis represents the voltage scale factor value and the X-axis represents the battery identification number.

[0149] The upper and lower limits of the reference range RR2 shown in Fig. 12 are 100.5% and 99.3%, respectively. From this, it can be seen that the average value of the first voltage scale factor to the (m-1)th voltage scale factor is (100.5+99.3) / 2=99.9%, and the tolerance is 0.6%. Compared to the reference range RR1 in Fig. 11, the average value is 0.1%p smaller and the tolerance is 0.2%p smaller.

[0150] 12, unlike FIG. 11, some voltage scale factors are out of the reference range RR2 of at least one of the plurality of pieces of adjustment information calculated by the control unit 120. In FIG.

[0151] The control unit 120 may check the battery identification number associated with the voltage scale factor outside the reference range RR2 and determine that the battery having the checked battery identification number is abnormal. In addition, the control unit 120 may determine that the battery array 20 is abnormal if the number of batteries determined to be abnormal is equal to or greater than a threshold value.

[0152] 13 illustrates yet another example distribution of voltage scale factors associated with a particular conditioning operation of the conditioning process, where the Y-axis represents the voltage scale factor value and the X-axis represents the battery identification number.

[0153] The upper and lower limits of the reference range RR3 shown in Fig. 13 are 101.0% and 99.0%, respectively. From this, it can be seen that the average value of the first voltage scale factor to the (m-1)th voltage scale factor is (101.0+99.0) / 2=100.0%, and the allowable value is 1.0%. Compared to the reference range RR1 in Fig. 11, the average value is the same, but the allowable value has increased by 0.2%p.

[0154] 13, one voltage scale factor F16 associated with battery identification number 16 among the (m-1) voltage scale factors is outside the reference range RR3. Therefore, the control unit 120 may determine that the battery with battery identification number 16 is abnormal.

[0155] The control unit 120 may determine the abnormality level of the battery determined to be abnormal. As an example, the abnormality level of the battery associated with the battery identification number 16 (i.e., B16) may have a predetermined positive correlation (e.g., proportionality) with the deviation amount of the voltage scale factor F16 associated with the battery identification number 16 from the reference range RR3. Since the voltage scale factor F16 associated with the battery identification number 16 is smaller than the lower limit value of the reference range RR3, the difference between the voltage scale factor F16 and the lower limit value of the reference range RR3 may be calculated as the deviation amount of the voltage scale factor F16. Conversely, if the voltage scale factor F16 is larger than the upper limit value of the reference range RR3, the difference between the voltage scale factor F16 and the upper limit value of the reference range RR3 may be calculated as the deviation amount of the voltage scale factor F16. The larger the deviation amount, the higher the abnormality level.

[0156] The control unit 120 may set a reference range based on the reference voltage profile R without calculating a representative value of a plurality of pieces of main adjustment information. In this case, the selected reference voltage profile R may be a voltage profile of a reference battery in an abnormal state, but even in such a case, the control unit 120 can diagnose the state of the battery B. This will be described with reference to FIG.

[0157] 14 is yet another example of a distribution of voltage scale factors associated with a particular conditioning operation of the conditioning process, where the Y-axis represents the voltage scale factor value and the X-axis represents the battery identification number.

[0158] Referring to FIG. 14, the control unit 120 may diagnose an abnormality in the first battery B1 to the m-th battery Bm or the battery array 20 by utilizing a predetermined reference range RR4 for a specific adjustment operation.

[0159] The reference range RR4 is related to the second adjustment operation, and has a median value of 100%, an upper limit value of 101.0% and a lower limit value of 99.0%, respectively, from which it can be seen that the tolerance value is 1%.

[0160] If only the reference battery is abnormal among the first battery B1 to the m-th battery Bm, the first comparative voltage profile to the (m-1)th comparative voltage profile should have a large deviation from the reference voltage profile R, and the voltage scale factors of the (m-1) batteries B excluding the reference battery should be biased toward a range greater than or less than 100%. FIG. 14 shows that all the voltage scale factors are biased upward beyond the upper limit 101.0% of the reference range RR4. In this case, the control unit 120 may diagnose whether the reference battery is abnormal based on the number of voltage scale factors out of the reference range RR4 among the (m-1) voltage scale factors. Naturally, if the number of voltage scale factors out of the reference range RR4 (99 in FIG. 14) is equal to or greater than a specific value (e.g., a natural number greater than or equal to m / 3 and less than m / 3+1), the reference battery may be identified as abnormal.

[0161] The diagnostic process utilizing the voltage scale factor associated with the second adjustment operation has been described above with reference to Figures 11 to 14. It goes without saying that the diagnostic process utilizing the distribution of the voltage scale factor associated with the second adjustment operation can also be commonly applied to diagnostic processes utilizing the distribution of the voltage shift factor associated with the first adjustment operation, the distribution of the capacitance shift factor associated with the third adjustment operation, and the distribution of the capacitance scale factor associated with the fourth adjustment operation.

[0162] According to the above-described method, the battery diagnostic device 100 can easily diagnose abnormal symptoms or the presence or absence of abnormalities for each battery by statistically analyzing adjustment results obtained for the entire battery without having to previously obtain reference data to be used for detecting abnormalities in the battery.

[0163] The battery diagnostic device 100 can identify a battery having an adjustment amount (e.g., a voltage scale factor) that is out of a reference range. The battery diagnostic device 100 can detect each battery to which an identification number related to an adjustment amount that is out of a reference range has been previously assigned for each adjustment operation. In this case, it is possible to individually diagnose which battery among the first battery B1 to the m-th battery Bm connected in series is in an abnormal state, and it is possible to take follow-up measures such as notifying the user of the abnormal battery, suspending use, or replacing the battery. In addition, the battery diagnostic device 100 can also diagnose whether the battery array 20 is abnormal depending on the number of batteries determined to be in an abnormal state.

[0164] The above-mentioned adjustment process for the first battery B1 to the m-th battery Bm may be executed every time a diagnosis-requiring event occurs. As an example, if the elapsed time (time difference) from the previous charging completion time to the current charging start time is equal to or greater than a predetermined reference time (e.g., one week) and / or if the accumulated charge / discharge capacity of the battery array 20 during the period from the previous charging completion time to the current charging start time is equal to or greater than a predetermined capacity (e.g., the design capacity of the battery array 20). As another example, the control unit 120 may count the number of times the battery pack 10 is charged, and determine that a diagnosis-requiring event has occurred every time the number of times the battery pack 10 is charged increases by a predetermined reference number.

[0165] The control unit 120 may select a reference battery in the current diagnostic process based on the result of the previous diagnostic process. The reference battery refers to a battery whose voltage profile is set to the reference voltage profile.

[0166] As an example, if only one of the first to fourth diagnostic operations was performed in the previous diagnostic process, the control unit 120 may select a specific battery for which the adjustment amount of the specific diagnostic operation performed previously was determined to be normal as the reference battery.

[0167] As another example, if at least two of the first to fourth diagnostic operations were performed in the previous diagnostic process, the control unit 120 may select a specific battery as the reference battery, in which the adjustment amounts of two or more previously performed adjustment operations were all determined to be normal.

[0168] As yet another example, if a fourth diagnostic operation was performed in the previous diagnostic process, the control unit 120 may select a battery associated with a capacity scale factor that is closest to the average or median among the adjustment amounts of the previous fourth diagnostic operation (i.e., the first capacity scale factor to the (m-1)th capacity scale factor) as the current reference battery.

[0169] As described above, the control unit 120 can optimize the distribution of adjustment amounts obtained for each adjustment operation of the diagnostic process by selecting a reference battery for the current diagnostic process based on the results of the previous diagnostic process.

[0170] When two or more batteries B are determined to be normal in the previous diagnostic process, the control unit 120 may select one battery that has no history of being selected as a reference battery or has the fewest history of being selected as a reference battery among the two or more batteries B as the reference battery in the current diagnostic process. As an example, the control unit 120 may select the battery with the smallest or largest identification number as the reference battery among the two or more batteries that have no history of being selected as a reference battery.

[0171] Meanwhile, the battery B has a characteristic that the lower the temperature, the slower the electrochemical reaction. As an example, the higher the temperature of the battery, the lower the internal resistance tends to be. In consideration of this, the control unit 120 may adjust the size of the reference range for at least one of the first to fourth adjusting operations based on the temperature of the battery array 20.

[0172] Specifically, the measurement unit 110 can measure the temperature of the battery array 20. The temperature of the battery array 20 can be treated as indicating the average temperature of the first battery B1 to the m-th battery Bm.

[0173] When the measured temperature is less than a predetermined lower limit temperature, the control unit 120 can expand the reference range to correspond to the difference between the measured temperature and the lower limit temperature.

[0174] When the measured temperature exceeds a predetermined upper limit temperature, the control unit 120 may reduce the reference range to correspond to the difference between the measured temperature and the lower limit temperature.

[0175] Assume that the reference temperature range is +10°C to +30°C. If the measured temperature is +20°C, the control unit 120 may maintain the reference range of 99.0% to 101.0%. If the measured temperature is +1°C, the control unit 120 may expand the reference range to correspond to a temperature difference of 9°C. If the measured temperature is +35°C, the control unit 120 may reduce the reference range to correspond to a temperature difference of 5°C. Here, the median value of the reference range (1 / 2 the sum of the upper limit value and the lower limit value) may be maintained. The relationship data of the reduction ratio and / or expansion ratio of the reference range according to the temperature difference between the upper limit temperature and / or the lower limit temperature of the reference temperature range and the temperature of the battery array 20 may be created in the form of a lookup table or the like and pre-recorded in the memory 130.

[0176] FIG. 15 is a diagram illustrating an example of a battery pack according to an embodiment of the present invention, and FIG. 16 is a diagram illustrating an example of an electric vehicle including the battery pack illustrated in FIG.

[0177] 15 , the battery pack 10 may include a pair of power terminals P+, P−, a battery array 20, and a battery diagnostic device 100. The battery pack 10 may further include a relay 30 and a fuse 40. A charger / discharger 300 may be included in the battery pack 10 or the electric vehicle 1.

[0178] At least some components of the battery diagnostic device 100 according to the present invention may be embodied as conventional components included in the battery pack 10. For example, the measurement unit 110 of the battery diagnostic device 100 according to the present invention may be embodied by a voltage sensor included in the battery pack 10.

[0179] The charging / discharging unit 300 may be configured to charge and / or discharge the battery array 20 in response to a command from the control unit 120. That is, the charging / discharging unit 300 may have only a charging function, or may have both a charging function and a discharging function. In the process of charging and / or discharging the battery array 20 by the charging / discharging unit 300, the measuring unit 110 may measure the voltage and current of each battery B included in the battery array 20.

[0180] 16, the battery pack 10 may be applied to an electric vehicle 1. That is, the electric vehicle 1 may include the battery diagnosis device 100 according to the present invention described above. In particular, in the case of the electric vehicle 1, the battery pack 10 as a power source is a very important component, so that the battery diagnosis device 100 according to the present invention may be more usefully applied. Of course, the electric vehicle 1 may further include a vehicle body, a vehicle control unit such as an electronic control unit (ECU), a motor, connection terminals, a DC-DC converter, etc. in addition to the battery pack 10.

[0181] 17 is a flow chart showing a battery diagnosis method according to an embodiment of the present invention. The method according to FIG. 17 can be executed by the battery diagnosis device 100 whenever a diagnosis-requiring event occurs.

[0182] 17, in step S1710, the control unit 120 collects voltage measurement data indicating the voltage of each of the first battery B1 to the m-th battery Bm connected in series from the measurement unit 110 while charging or discharging the battery array 20. The control unit 120 may collect current measurement data indicating a current flowing through the battery array 20 from the measurement unit 110 in parallel with collecting the voltage measurement data. In step S1710, if the magnitude of the accumulated capacity reaches a predetermined critical capacity or the voltage of at least one battery among the first battery B1 to the m-th battery Bm reaches a predetermined upper limit voltage, the process proceeds from step S1710 to step S1720.

[0183] In step S1720, the control unit 120 generates a first voltage profile to an m-th voltage profile indicating a change history of the voltage of each of the first battery B1 to the m-th battery Bm. The i-th voltage profile may be a time series of measured values ​​of the voltage of the i-th battery Bi according to time or capacity.

[0184] In operation S1730, the control unit 120 sets one of the first to m-th voltage profiles as a reference voltage profile, and the remaining (m-1) voltage profiles excluding the reference voltage profile may be set as the first to (m-1)th comparison voltage profiles.

[0185] In operation S1740, the control unit 120 compares the first comparison voltage profile to the (m-1)th comparison voltage profile with the reference voltage profile, respectively, to diagnose the battery array.

[0186] FIG. 18 is a flow diagram showing an example of a sub-routine that may be included in step S1740 of FIG.

[0187] Referring to FIG. 18, step S1740 may include steps S1810 to S1830 as its subroutines.

[0188] In step S1810, the control unit 120 adjusts the first comparison voltage profile through the (m-1)th comparison voltage profile, respectively, so that the amount of error from the reference voltage profile is minimized, thereby generating the first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile. In detail, an adjustment process including at least one of the first adjustment operation through the fourth adjustment operation is executed for each of the first comparison voltage profile through the (m-1)th comparison voltage profile, and as a result, the first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile are generated. That is, the jth adjusted comparison voltage profile is obtained from the jth comparison voltage profile.

[0189] In step S1820, the control unit 120 generates first main adjustment information through (m-1)th main adjustment information indicating adjustment levels from the first comparison voltage profile through the (m-1)th comparison voltage profile to the first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile. The jth main adjustment information includes at least one of a jth voltage shift factor that is an adjustment amount due to the first adjusting operation, a jth voltage scale factor that is an adjustment amount due to the second adjusting operation, a jth capacitance shift factor that is an adjustment amount due to the third adjusting operation, and a jth capacitance scale factor that is an adjustment amount due to the fourth adjusting operation.

[0190] In step S1830, the control unit 120 diagnoses whether or not there is an abnormality in each of the first battery B1 to the m-th battery Bm or the battery array 20 based on the first main adjustment information to the (m-1)th main adjustment information. In detail, the control unit 120 may detect an abnormality in at least one of the battery B and the battery array 20 by analyzing a distribution of adjustment amounts of at least one adjustment operation included in the first main adjustment information to the (m-1)th main adjustment information.

[0191] As an example, the control unit 120 may diagnose whether there is an abnormality in each of the first battery B1 to the mth battery Bm or whether there is an abnormality in the battery array 20 based on at least one of the result data set of the first adjustment operation, the result data set of the second adjustment operation, the result data set of the third adjustment operation, and the result data set of the fourth adjustment operation.

[0192] Here, the result data set of the first adjustment operation is referred to as the first voltage shift factor through the (m-1)th voltage shift factor. The result data set of the second adjustment operation is referred to as the first voltage scale factor through the (m-1)th voltage scale factor. The result data set of the third adjustment operation is referred to as the first capacitance shift factor through the (m-1)th capacitance shift factor. The result data set of the fourth adjustment operation is referred to as the first capacitance scale factor through the (m-1)th capacitance scale factor.

[0193] FIG. 19 is a flow diagram illustrating an example of a sub-routine that may be added to step S1740 of FIG.

[0194] 19, step S1740 may include steps S1910 to S1950 as its subroutines. The method of FIG. 19 may be executed in parallel with the method of FIG. 18 or after the method of FIG.

[0195] In operation S1910, the control unit 120 generates a reference differential voltage profile from the reference voltage profile.

[0196] In operation S1920, the control unit 120 generates the first comparative differential voltage profile through the (m-1)th comparative differential voltage profile from the first comparative voltage profile through the (m-1)th comparative voltage profile.

[0197] In step S1930, the control unit 120 adjusts the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile, respectively, so as to minimize the amount of error from the reference differential voltage profile, thereby generating the first adjusted comparative differential voltage profile to the (m-1)th adjusted comparative differential voltage profile.

[0198] In step S1940, the control unit 120 generates first sub-adjustment information to the (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile to the first adjusted comparative differential voltage profile to the (m-1)th adjusted comparative differential voltage profile.

[0199] In step S1950, the control unit 120 further diagnoses whether each of the first battery B1 to the m-th battery Bm or the battery array 20 is abnormal, further based on the first sub-adjustment information to the (m-1)th sub-adjustment information based on the differential voltage curve.

[0200] FIG. 20 is a flow diagram illustrating another example of a sub-routine that may be added to step S1740 of FIG.

[0201] 20, step S1740 may include steps S2010 to S2050 as its subroutines. The method of FIG. 20 may be executed in parallel with the method of FIG. 18 and / or the method of FIG. 19, or may be executed after at least one of the method of FIG. 18 and the method of FIG. 19 is completed.

[0202] In step S2010, the control unit 120 generates a reference differential capacitance profile from the reference voltage profile.

[0203] In step S2020, the control unit 120 generates a first comparative differential capacitance profile through a (m-1)th comparative differential capacitance profile from the first comparative voltage profile through the (m-1)th comparative voltage profile.

[0204] In step S2030, the control unit 120 adjusts the first comparative differential capacity profile to the (m-1)th comparative differential capacity profile, respectively, so as to minimize the amount of error from the reference differential capacity profile, thereby generating the first adjusted comparative differential capacity profile to the (m-1)th adjusted comparative differential capacity profile.

[0205] In step S2040, the control unit 120 generates first sub-adjustment information to the (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential capacity profile to the (m-1)th comparative differential capacity profile to the first adjusted comparative differential capacity profile to the (m-1)th adjusted comparative differential capacity profile. The first sub-adjustment information to the (m-1)th sub-adjustment information in the method of Fig. 20 are adjustment information based on a differential capacity curve, and are distinguished from the first sub-adjustment information to the (m-1)th sub-adjustment information in the method of Fig. 19 described above, which are adjustment information based on a differential voltage curve.

[0206] In step S2050, the control unit 120 diagnoses whether each of the first battery B1 to the m-th battery Bm or the battery array 20 is abnormal, further based on the first sub-adjustment information to the (m-1)th sub-adjustment information based on the differential capacity curve.

[0207] When all of the methods shown in Figures 18 to 20 have been executed, the control unit 120 may ultimately determine that each battery that is commonly diagnosed as abnormal by these methods is an abnormal battery, and assign an abnormality confirmation flag to the identification number of the battery determined to be abnormal.

[0208] The control unit 120 may determine that a battery diagnosed as abnormal by only one or two of the three methods in Figs. 18 to 20 is normal, and may assign an abnormality suspicion flag to the identification number of the corresponding battery.

[0209] The control unit 120 may ultimately determine each battery diagnosed as normal by all three methods according to Figs. 18 to 20 as a normal battery, and may assign a normality confirmation flag to the identification number of the battery determined to be normal.

[0210] The control unit 120 may determine the order of diagnosis for the first battery B1 to the m-th battery Bm in the current diagnostic process based on the diagnostic flag (abnormality confirmation flag, abnormality suspicion flag, or normality confirmation flag) assigned to each of the first battery B1 to the m-th battery Bm in the previous diagnostic process. The control unit 120 may diagnose whether or not the battery with the identification number assigned with the abnormality suspicion flag is abnormal, rather than the battery with the identification number assigned with the normality confirmation flag in the previous diagnostic process. As an example, if the identification number of the first battery B1 was assigned with the abnormality suspicion flag and the identification number of the second battery B2 was assigned with the normality confirmation flag in the previous diagnostic process, the control unit 120 may compare the adjustment amount related to the first battery B1 with the reference range before the adjustment amount related to the second battery B2 to confirm whether or not the first battery B1 is abnormal.

[0211] The above-described embodiments of the present invention may be embodied not only by an apparatus and a method, but also through a program that realizes functions corresponding to the configuration of the embodiments of the present invention or a recording medium on which the program is recorded, and such implementation would be easily embodied by a person skilled in the art from the description of the above-described embodiments.

[0212] As described above, the present invention has been described using limited embodiments and drawings. However, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention belongs within the technical spirit of the present invention and the equivalent scope of the claims.

[0213] Furthermore, the present invention described above is susceptible to various substitutions, modifications and alterations by those having ordinary knowledge in the technical field to which the present invention pertains, within the scope not departing from the technical spirit of the present invention, and is not limited to the above-described embodiments and the accompanying drawings, but may be configured by selectively combining all or part of each embodiment for various modifications.

Claims

1. A battery diagnostic device for a battery array including a first battery to an m-th battery (m being a natural number of 3 or more) connected in series, comprising: A sensing unit configured to detect the voltages of the first battery to the mth battery, and a control unit configured to generate a first voltage profile to an mth voltage profile indicating a voltage change history of each of the first battery to the mth battery based on voltage measurement data collected from the sensing unit during charging or discharging of the battery array; The control unit is a reference voltage profile which is one of the first voltage profile to the mth voltage profile, and a first comparison voltage profile to an (m-1)th comparison voltage profile which are the remaining (m-1) voltage profiles other than the reference voltage profile, to diagnose the battery array.

2. The control unit is adjusting the first comparative voltage profile to the (m-1)th comparative voltage profile, respectively, to generate a first adjusted comparative voltage profile to an (m-1)th adjusted comparative voltage profile so that an error amount from the reference voltage profile is minimized; generating first main adjustment information to (m-1)th main adjustment information indicating adjustment levels from the first comparative voltage profile to the (m-1)th comparative voltage profile to the first adjusted comparative voltage profile to the (m-1)th adjusted comparative voltage profile; 2. The battery diagnostic device according to claim 1, configured to diagnose the battery array based on the first main adjustment information to the (m-1)th main adjustment information.

3. The control unit is 3. The battery diagnostic device according to claim 2, wherein the device is configured to determine a sum of squares or a root mean square error of a difference between a voltage of a j-th adjusted comparison voltage profile (j is a natural number less than m) among the first adjusted comparison voltage profile to the (m-1)-th adjusted comparison voltage profile and a voltage of the reference voltage profile as the amount of error between the j-th comparison voltage profile and the reference voltage profile.

4. The control unit is configured to determine a jth voltage shift factor from the jth comparison voltage profile to the jth adjusted comparison voltage profile; The battery diagnostic device of claim 2, wherein a j-th main adjustment information among the first to (m-1)-th main adjustment information includes the j-th voltage shift factor.

5. The control unit is 5. The battery diagnostic device according to claim 4, configured to diagnose an abnormality in each of the first battery to the mth battery or the battery array based on distributions of the first voltage shift factor to the (m-1)th voltage shift factor of the first main adjustment information to the (m-1)th main adjustment information.

6. The control unit is configured to determine a jth voltage scale factor from the jth comparison voltage profile to the jth adjusted comparison voltage profile; The battery diagnostic device of claim 2, wherein a j-th main adjustment information among the first to (m-1)-th main adjustment information includes the j-th voltage scale factor.

7. The control unit is 7. The battery diagnostic device according to claim 6, configured to diagnose an abnormality in each of the first battery to the mth battery or the battery array based on a distribution of the first voltage scale factor to the (m-1)th voltage scale factor of the first main adjustment information to the (m-1)th main adjustment information.

8. The control unit is generating a reference differential voltage profile from the reference voltage profile; generating a first comparative differential voltage profile through an (m-1)th comparative differential voltage profile from the first comparative voltage profile through the (m-1)th comparative voltage profile; adjusting the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile, respectively, so that an amount of error from the reference differential voltage profile is minimized, thereby generating a first adjusted comparative differential voltage profile to an (m-1)th adjusted comparative differential voltage profile; generating first sub-adjustment information to (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile to the first adjusted comparative differential voltage profile to the (m-1)th adjusted comparative differential voltage profile; The battery diagnostic device according to claim 2, further configured to diagnose an abnormality in each of the first battery to the mth battery or the battery array based on the first sub-adjustment information to the (m-1)th sub-adjustment information.

9. The control unit is configured to determine a jth differential voltage shift factor from the jth comparative differential voltage profile to the jth adjusted comparative differential voltage profile; The battery diagnostic device of claim 8, wherein a j-th sub-adjustment information among the first sub-adjustment information to the (m-1)-th sub-adjustment information includes the j-th differential voltage shift factor.

10. The control unit is configured to determine a jth derivative voltage scale factor from the jth comparative derivative voltage profile to the jth adjusted comparative derivative voltage profile; The battery diagnostic device of claim 8, wherein a j-th sub-adjustment information among the first to (m-1)-th sub-adjustment information includes the j-th differential voltage scale factor.

11. A battery pack comprising the battery diagnostic device according to any one of claims 1 to 10.

12. 12. An electric vehicle comprising the battery pack of claim 11.

13. A battery diagnostic method for a battery array including a first battery to an m-th battery (m being a natural number of 3 or more) connected in series, comprising: collecting voltage measurement data indicative of a voltage of each of the first through mth batteries during charging or discharging of the battery array; generating first to m-th voltage profiles indicating a change history of the voltages of the first to m-th batteries based on the voltage measurement data; and diagnosing the battery array by comparing a reference voltage profile, which is one of the first voltage profile to the mth voltage profile, with a first comparison voltage profile to an (m-1)th comparison voltage profile, which are the remaining (m-1) voltage profiles other than the reference voltage profile.

14. The step of diagnosing the battery array includes: adjusting the first comparison voltage profile through the (m-1)th comparison voltage profile, respectively, to generate a first adjusted comparison voltage profile through an (m-1)th adjusted comparison voltage profile so that an error amount from the reference voltage profile is minimized; generating first main adjustment information through (m-1)th main adjustment information indicating adjustment levels from the first comparison voltage profile through the (m-1)th comparison voltage profile to the first adjusted comparison voltage profile through the (m-1)th adjusted comparison voltage profile; and diagnosing an abnormality in each of the first battery to the mth battery or the battery array based on the first main adjustment information to the (m-1)th main adjustment information.

15. generating a reference differential voltage profile from the reference voltage profile; generating a first comparative differential voltage profile through an (m-1)th comparative differential voltage profile from the first comparative voltage profile through the (m-1)th comparative voltage profile; adjusting the first comparative differential voltage profile through the (m-1)th comparative differential voltage profile, respectively, so that an error amount from the reference differential voltage profile is minimized, thereby generating a first adjusted comparative differential voltage profile through an (m-1)th adjusted comparative differential voltage profile; generating first sub-adjustment information to (m-1)th sub-adjustment information indicating adjustment levels from the first comparative differential voltage profile to the (m-1)th comparative differential voltage profile to the first adjusted comparative differential voltage profile to the (m-1)th adjusted comparative differential voltage profile; The step of diagnosing the battery array includes: The battery diagnosis method according to claim 13, further comprising diagnosing the battery array further based on the first sub-adjustment information to the (m-1)th sub-adjustment information.

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