Battery management apparatus and operation method thereof

Abstract

A battery management apparatus according to one embodiment disclosed in the present document comprises: an interface for acquiring a voltage profile that indicates a change in voltage of each of a plurality of battery cells over time; and a processor, which divides the voltage profile into a plurality of time sections so as to detect whether the plurality of battery cells are abnormal on the basis of first voltage parameters related to the average voltage of the plurality of battery cells that correspond to each of the plurality of time sections, and second voltage parameters related to the difference between the first voltage parameters between adjacent time sections from among the plurality of time sections.

Description

Battery management device and its operating method

[0001] Cross-citation with related applications

[0002] This invention claims the benefit of priority from Korean Patent Application No. 10-2024-0050745, filed on April 16, 2024, and all contents of the document in that Korean Patent Application are incorporated herein by reference.

[0003] Technology field

[0004] The embodiments disclosed in this document relate to a battery management device and a method of operating the same.

[0005] Recently, active research and development has been conducted on secondary batteries. The term "secondary battery" refers to a rechargeable battery, encompassing both conventional Ni / Cd and Ni / MH batteries, as well as more recent lithium-ion batteries. Among secondary batteries, lithium-ion batteries boast a significantly higher energy density than conventional Ni / Cd and Ni / MH batteries. Furthermore, lithium-ion batteries can be manufactured in a compact and lightweight form, making them a popular power source for mobile devices. Recently, their use has expanded to include power sources for electric vehicles, drawing attention as a next-generation energy storage medium.

[0006] Secondary batteries gradually deteriorate through repeated charging and discharging, but accurately predicting and detecting deterioration or defects in secondary batteries remains challenging. To predict abnormal behavior in secondary batteries, methods are used to predict battery characteristics based on the open circuit voltage (OCV) at rest. However, accurately detecting the cause of abnormal behavior in secondary batteries based on the open circuit voltage at rest remains challenging.

[0007] One purpose of the embodiments disclosed in this document is to provide a battery management device and an operating method thereof for diagnosing the cause of abnormal behavior of a battery cell based on an open circuit voltage profile of the battery cell in an idle state.

[0008] The technical problems of the embodiments disclosed in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0009] A battery management device according to an embodiment disclosed in the present document may include an interface for obtaining a voltage profile representing a change in voltage of each of a plurality of battery cells over time; and a processor for dividing the voltage profile into a plurality of time periods and detecting whether the plurality of battery cells are abnormal based on a first voltage parameter related to an average voltage of the plurality of battery cells corresponding to each of the plurality of time periods and a second voltage parameter related to a difference between the first voltage parameters between adjacent time periods among the plurality of time periods.

[0010] According to one embodiment, the interface acquires the voltage profile whenever the SoC of the plurality of battery cells reaches a preset threshold value, and a length of an earlier time period among the plurality of time periods may be shorter than a length of another time period.

[0011] According to one embodiment, the first voltage parameter may include data related to an average rate of change of an average voltage of the plurality of battery cells in each of the plurality of time periods.

[0012] According to one embodiment, the second voltage parameter may correspond to a difference value between the first parameters corresponding to each adjacent time interval among the plurality of time intervals.

[0013] According to one embodiment, the processor is a battery management device that calculates a deviation between the second voltage parameters based on the following mathematical expression 1.

[0014] [Mathematical Formula 1]

[0015]

[0016] (Here, X corresponds to the deviation between the second voltage parameters, corresponds to the second voltage parameter, corresponds to the first voltage parameter, and the time interval T-1 corresponds to the time interval adjacent to the time interval T.)

[0017] According to one embodiment, the processor can detect that a battery cell with a disconnected tab exists among the plurality of battery cells when a deviation between the second parameters is greater than a preset reference value.

[0018] An operating method of a battery management device according to an embodiment disclosed in the present document may include the steps of: obtaining a voltage profile indicating a change in voltage of each of a plurality of battery cells over time; dividing the voltage profile into a plurality of time sections; calculating an average voltage of the plurality of battery cells corresponding to each of the plurality of time sections; calculating an average rate of change of the average voltage of the plurality of battery cells in each of the plurality of time sections; and detecting an abnormality of the plurality of battery cells based on a deviation between the average rates of change in adjacent time sections among the plurality of time sections.

[0019] According to one embodiment, the voltage profile may include data indicating a change in voltage of each of the plurality of battery cells over time from a point in time when the plurality of battery cells reach a charge completion or discharge completion state.

[0020] In one embodiment, the length of the earliest time interval among the plurality of time intervals may be shorter than the lengths of the other time intervals.

[0021] According to one embodiment, the deviation between the average change rates can be calculated based on the following mathematical expression 1.

[0022] [Mathematical Formula 1]

[0023]

[0024] (Here, X corresponds to the deviation between the above average rates of change, corresponds to the difference between the average rates of change in adjacent time intervals, corresponds to the above average rate of change, and time point T-1 corresponds to a time point adjacent to time point T.)

[0025] According to one embodiment, the step of detecting an abnormality in the plurality of battery cells may include a step of detecting that a battery cell with a disconnected tab exists among the plurality of battery cells when the deviation is greater than a preset reference value.

[0026] A battery management device according to an embodiment disclosed in this document can effectively detect a tab disconnection of a battery cell.

[0027] The effects according to the embodiments disclosed in this document are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art according to the disclosure of this document.

[0028] FIG. 1 is a drawing for explaining a battery pack according to an embodiment disclosed in this document.

[0029] FIG. 2 is a drawing for explaining a battery management device according to an embodiment disclosed in this document.

[0030] FIG. 3 is a drawing for explaining a voltage profile according to an embodiment disclosed in this document.

[0031] FIG. 4 is a diagram for explaining voltage parameters according to an embodiment disclosed in this document.

[0032] FIG. 5 is a flowchart for explaining the operation of a battery management device according to an embodiment disclosed in this document.

[0033] FIG. 6 is a drawing for explaining a computing system equipped with a battery management device according to an embodiment disclosed in this document.

[0034] Hereinafter, embodiments disclosed in this document will be described in detail with reference to exemplary drawings. When designating components in each drawing, it should be noted that, where possible, identical components are given identical reference numerals, even if they appear in different drawings. Furthermore, when describing embodiments disclosed in this document, detailed descriptions of related known structures or functions will be omitted if they are deemed to hinder understanding of the embodiments disclosed in this document.

[0035] In describing the components of the embodiments disclosed in this document, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only intended to distinguish the components from other components and do not limit the nature, order, or sequence of the components. In addition, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiments disclosed in this document belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined in this application.

[0036] FIG. 1 is a drawing for explaining a battery pack according to an embodiment disclosed in this document, and FIG. 2 is a drawing for explaining a battery management device according to an embodiment disclosed in this document.

[0037] First, referring to FIG. 1, a battery pack (1) may include a battery module (10) and a battery management device (100).

[0038] The battery module (10) may include a plurality of battery cells (11, 12, 13, 14). In FIG. 1, the battery module (10) is illustrated as including four battery cells, but is not limited thereto, and the battery module (10) may be configured to include n battery cells (n is a natural number greater than or equal to 2).

[0039] The plurality of battery cells (11, 12, 13, 14) may be, but are not limited to, lithium ion (Li-ion) batteries, lithium ion polymer (Li-ion Polymer) batteries, nickel cadmium (Ni-Cd) batteries, nickel metal hydride (Ni-MH) batteries, etc. In addition, although the battery pack (1) in FIG. 1 is illustrated as including one battery module (10), the battery pack (1000) may be configured to include n (n is a natural number greater than or equal to 2) battery modules according to an embodiment.

[0040] The battery pack (1) may be configured to supply power to a target device (not shown). For this purpose, the battery pack (1) may be electrically connected to the target device. Here, the target device may include any electrical, electronic, or mechanical device that operates by receiving power from the battery pack (1). For example, the target device may be, but is not limited to, a two-wheeled electric vehicle such as an electric vehicle (EV) or an electric scooter. In addition, when the target device is a two-wheeled electric vehicle such as an electric scooter, the battery pack (1) mounted on the two-wheeled electric vehicle may be replaceable through a battery swapping station (BSS).

[0041] The battery management device (100) can manage and / or control the status and / or operation of the battery module (10). For example, the battery management device (100) can manage and / or control the status and / or operation of a plurality of battery cells (11, 12, 13, 14) included in the battery module (10), or manage charging and / or discharging of the battery module (10).

[0042] The battery management device (100) can monitor the voltage, current, temperature, etc. of the battery module (10) and each of the plurality of battery cells (11, 12, 13, 14). To this end, sensors or various measuring modules not shown in FIG. 1 may be additionally installed at any location within the battery module (10) or battery pack (1) or in the charging / discharging path.

[0043] The battery management device (100) can calculate parameters indicating the state of the battery module (10), such as SOC (State of Charge) or SOH (State of Health), based on measured values ​​such as monitored voltage, current, and temperature.

[0044] The battery management device (100) may be configured to diagnose the deterioration of a plurality of battery cells (11, 12, 13, 14) and / or detect a battery cell in which an abnormality has occurred among the plurality of battery cells (11, 12, 13, 14). Details related to this will be described later in the description of FIG. 2.

[0045] Referring to FIG. 2, the battery management device (100) may include an interface (110), a processor (120), and a memory (130).

[0046] The interface (110) can obtain a voltage profile of each of the plurality of battery cells (11, 12, 13, 14, see FIG. 1). Here, the voltage profile may include, but is not limited to, a graph showing a change in the voltage of each of the plurality of battery cells (11, 12, 13, 14) over time. The interface (110) can measure and / or predict the voltage of each of the plurality of battery cells (11, 12, 13, 14) based on the current flowing in the battery pack (1, see FIG. 1) and / or the internal resistance.

[0047] According to one embodiment, the interface (110) may obtain a voltage profile by applying voltage and / or current to a plurality of battery cells (11, 12, 13, 14). In this case, the interface (110) may include various circuits for applying voltage and / or current to the plurality of battery cells (11, 12, 13, 14) and a processor for calculating and / or processing the obtained voltage profile.

[0048] According to one embodiment, the interface (110) can indirectly obtain the voltage profile of each of the plurality of battery cells (11, 12, 13, 14). In this case, the interface (110) may further include a communication module for communicating with the battery pack (1) via wires and / or wirelessly.

[0049] According to one embodiment, the interface (110) can obtain a voltage profile of the plurality of battery cells (11, 12, 13, 14) whenever the SoC (State of Charge) of each of the plurality of battery cells (11, 12, 13, 14) reaches a preset threshold value. Here, the preset threshold value may be, but is not limited to, 100% or 0%, which are values ​​indicating a state in which charging is completed and / or discharging is completed. The interface (110) can obtain a voltage profile indicating a change in voltage of each of the plurality of battery cells (11, 12, 13, 14) over time from the point in time when each of the plurality of battery cells (11, 12, 13, 14) is charged and / or discharged.

[0050] According to one embodiment, the interface (110) can obtain the voltage profile of each of the plurality of battery cells (11, 12, 13, 14) until the voltage of each of the plurality of battery cells (11, 12, 13, 14) reaches a rest voltage.

[0051] The processor (120) can control the overall operation of the battery management device (100). Here, the processor can execute software to control the operation of at least one other component (e.g., hardware or software) of the battery management device (100), or perform operations such as processing and / or calculating various data. In addition, referring to FIG. 2, the battery management device (100) is illustrated as including one processor (120), but is not limited thereto, and the battery management device (100) can be configured to include at least one processor.

[0052] The processor (120) may be configured to detect a battery cell in which an abnormality has occurred among the plurality of battery cells (11, 12, 13, 14) based on the voltage profile of each of the plurality of battery cells (11, 12, 13, 14). The processor (120) may calculate various voltage parameters for detecting an abnormality in the plurality of battery cells (11, 12, 13, 14) based on the voltage profile of each of the plurality of battery cells (11, 12, 13, 14).

[0053] According to one embodiment, the processor (120) may divide the voltage profiles of each of the plurality of battery cells (11, 12, 13, 14) into a plurality of time periods. The processor (120) may calculate various voltage parameters based on the voltage profiles of the plurality of battery cells (11, 12, 13, 14) corresponding to each of the divided plurality of time periods. Here, the length of each of the time periods may be the same or different, and is not limited to a specific example.

[0054] The processor (120) may calculate a first voltage parameter and a second voltage parameter for detecting an abnormality of a plurality of battery cells (11, 12, 13, 14) based on voltage profiles in each of a plurality of time periods. According to one embodiment, the first voltage parameter may be related to an average voltage of the plurality of battery cells (11, 12, 13, 14), and the second voltage parameter may be related to a difference between the first voltage parameters in adjacent time periods.

[0055] According to one embodiment, the first voltage parameter may be calculated based on an average voltage of the plurality of battery cells (11, 12, 13, 14) in each of the plurality of time periods. For example, the first voltage parameter may be related to an average voltage, which is an average value of the voltages of the plurality of battery cells (11, 12, 13, 14) in each of the plurality of time periods, and the first voltage parameter may include, but is not limited to, data related to an average rate of change of the average voltage of the plurality of battery cells (11, 12, 13, 14) in each of the plurality of time periods.

[0056] According to one embodiment, the second voltage parameter may include, but is not limited to, data related to a difference between the first voltage parameter between adjacent time periods among the plurality of time periods, i.e., an average rate of change of the average voltage of the plurality of battery cells (11, 12, 13, 14) in each of the plurality of time periods. Here, the adjacent time period may be any one of the preceding time period and / or the succeeding time period and is not limited to a specific example.

[0057] The processor (120) can calculate a deviation of the second voltage parameter. According to one embodiment, the processor (120) can detect an abnormality in the plurality of battery cells (11, 12, 13, 14) based on a comparison result between the calculated deviation of the second voltage parameter and a preset reference value. For example, if the deviation of the second voltage parameter is greater than the preset reference value, the processor (120) can diagnose that a battery cell with a disconnected tab exists among the plurality of battery cells (11, 12, 13, 14). As another example, if the deviation of the second voltage parameter is less than the preset reference value, the processor (120) can diagnose that a polarization phenomenon has occurred in the plurality of battery cells (11, 12, 13, 14).

[0058] The memory (130) can store various data (e.g., commands, data related to mathematical formulas, voltage profiles of a plurality of battery cells, data related to reference values) for the operation of the battery management device (100). According to one embodiment, the memory (130) can include, but is not limited to, a volatile memory device such as a static random access memory (SRAM) or a dynamic random access memory (DRAM), or a non-volatile memory device such as a read only memory (ROM), a programmable ROM (PROM), or a flash memory.

[0059] According to one embodiment, the battery management device (100) may be formed integrally with a battery pack (1, see FIG. 1). In this case, the battery management device (100) may be implemented as a module BMS (Battery Management System; BMS) that controls the overall operation of the battery module (10, see FIG. 1) or a pack BMS that controls the overall operation of the battery pack (1), but is not limited thereto.

[0060] According to one embodiment, the battery management device (100) may be formed separately from the battery pack (1). In this case, the battery management device (100) may be connected to the battery module (10) and / or the battery pack (1) including the same via a wired and / or wireless network, and the battery management device (100) may be implemented through various devices such as a cloud server, a charger, or a charger / discharger.

[0061] According to one embodiment, the battery management device (100) can transmit the degradation level (e.g., SOH, etc.), diagnosis results, etc. of each of the plurality of battery cells (11, 12, 13, 14) to an external source (e.g., a cloud server or a user terminal). The cloud server can be configured to provide the degradation level and / or diagnosis results, etc. of each of the plurality of battery cells (11, 12, 13, 14) to a plurality of users, and the user terminal may include, but is not limited to, a terminal such as a personal computer (PC) or a smartphone.

[0062] According to one embodiment, the battery management device (100) may be implemented through a BSS (Battery Swapping Station; BSS). Here, the BSS may be a system having a slot into which a battery pack (1) can be inserted and capable of charging the inserted battery pack (1).

[0063] FIG. 3 is a drawing for explaining a voltage profile according to an embodiment disclosed in this document, and FIG. 4 is a drawing for explaining a voltage parameter according to an embodiment disclosed in this document.

[0064] First, referring to FIG. 3, multiple voltage profiles are shown relating to changes in voltage over time for each of multiple battery cells (11, 12, 13, 14, see FIG. 1).

[0065] According to one embodiment, the horizontal axis of the graph illustrated in FIG. 3 may represent time (t, sec), and the vertical axis may represent voltage (V). For convenience of explanation, the plurality of battery cells (11, 12, 13, 14) are assumed to be in a charging state, but the present invention is not limited thereto, and the same may be applied to battery cells in a discharged state.

[0066] After the charging of the plurality of battery cells (11, 12, 13, 14) is completed, each of the plurality of battery cells (11, 12, 13, 14) enters a resting state. The voltage of each of the plurality of battery cells (11, 12, 13, 14) gradually decreases as it enters the resting state, and after about 4000 s has elapsed, the voltage of each of the plurality of battery cells (11, 12, 13, 14) gradually converges to a resting voltage with a small amount of change.

[0067] The processor (120, see FIG. 2) can divide the voltage profile of each of the plurality of battery cells (11, 12, 13, 14) into a plurality of time periods. According to one embodiment, the processor (120) can divide the time periods from the time at which each of the plurality of battery cells (11, 12, 13, 14) enters an idle state into n (n is a positive integer) time periods. As illustrated in FIG. 3, the earliest time period may be the first time period, T1 period, and the latest time period may be the last time period, Tn period.

[0068] According to one embodiment, the length of each of the plurality of time intervals (T1 to Tn) may be equal to and / or different from each other.

[0069] According to one embodiment, when the lengths of each of the plurality of time sections (T1 to Tn) are different from each other, the processor (120) may set the length of the T1 section, which is the earliest time section, to be shorter than the lengths of the other time sections (T2 to Tn). This is because the voltage change of the battery cells (11, 12, 13, 14) that have entered the rest state is relatively large in the earlier time sections. In order to effectively detect such voltage change, the processor (120) may set the length of the T1 section, which is the earliest time section, to be shorter than the lengths of the other time sections. However, this is exemplary, and the processor (120) may set the lengths of the time sections in various ways, such as setting the lengths of the plurality of earliest time sections to be shorter than the lengths of the other time sections, depending on the design.

[0070] The processor (120) can calculate the average voltage of each of the plurality of battery cells (11, 12, 13, 14) in each of the plurality of time periods. For example, the processor (120) can calculate the average of the voltages of each of the plurality of battery cells (11, 12, 13, 14) in the first time period (T1) and generate a graph representing the average of the voltages of the plurality of battery cells (11, 12, 13, 14) in the first time period (T1). Similarly, the processor (120) can calculate the average of the voltages of each of the plurality of battery cells (11, 12, 13, 14) in a second time period (T2) following the first time period (T1), and the processor (120) can calculate the average of the voltages of each of the plurality of battery cells (11, 12, 13, 14) for each of all time periods (T1 to Tn) to generate a graph representing the average voltages of the plurality of battery cells (11, 12, 13, 14).

[0071] The processor (120) can calculate the average rate of change of the average voltage of each of the plurality of battery cells (11, 12, 13, 14) in each of all time periods (T1 to Tn). Here, the average rate of change can be defined as the rate of change of the average voltage per unit time, and the average voltage of each of the plurality of battery cells (11, 12, 13, 14) and the average rate of change of the average voltage of each of the plurality of battery cells (11, 12, 13, 14) calculated based thereon can be included in the first voltage parameter, but is not limited thereto.

[0072] The processor (120) can calculate a second voltage parameter related to the difference between the average change rates based on the average change rates of the average voltages of the plurality of battery cells (11, 12, 13, 14) in each of all time periods (T1 to Tn). According to one embodiment, the processor (120) may calculate the difference between the average rate of change in the average voltage of the plurality of battery cells (11, 12, 13, 14) corresponding to the second time period (T2) and the average rate of change in the average voltage of the plurality of battery cells (11, 12, 13, 14) corresponding to the first time period (T1), and may calculate the difference between the average rate of change in the average voltage of the plurality of battery cells (11, 12, 13, 14) corresponding to the third time period (T3) and the average rate of change in the average voltage of the plurality of battery cells (11, 12, 13, 14) corresponding to the second time period (T2). Likewise, the processor (120) may repeat the above-described calculation operation until calculating the difference between the average rate of change in the average voltage of the plurality of battery cells (11, 12, 13, 14) corresponding to the n-th time period (Tn) and the average rate of change in the average voltage of the plurality of battery cells (11, 12, 13, 14) corresponding to the n-1-th time period (Tn-1).

[0073] In this regard, referring to FIG. 4, a graph representing the relationship between the first voltage parameter and the second voltage parameter is illustrated. As illustrated in FIG. 3, the horizontal axis of the graph illustrated in FIG. 4 may represent time (t), and the vertical axis may represent voltage (V).

[0074] Referring to FIG. 4, the second time period (T2) may be a time period between time points t1 and t2. The processor (120, see FIG. 1) may calculate the first voltage parameter (V1) of each of the second time period (T2) and the first time period (T1), which is a time period preceding the second time period (T2). Here, the first voltage parameter (V1(t1)) at time point t1 may correspond to the first voltage parameter value at the first time period (T1), and the first voltage parameter (V1(t2)) at time point t2 may correspond to the first voltage parameter value at the second time period (T2).

[0075] According to one embodiment, the processor (120) may calculate the difference between the first voltage parameter in the second time period (T2) and the first voltage parameter in the first time period (T1). Here, the difference between the first voltage parameter in the nth time period (Tn) and the first voltage parameter in the (n-1)th time period (Tn-1) may be defined as V2(tn). That is, as illustrated in FIG. 4, the second voltage parameter (V2(t2)) at time point t2 may correspond to a difference value between the first voltage parameter in each of the second time period (T2) and the first time period (T1).

[0076] According to one embodiment, the processor (120) may calculate the second voltage parameter through various data processing methods. For example, the processor (120) may calculate the deviation described below based on the absolute value of the calculated second voltage parameter, but is not limited thereto.

[0077] The processor (120) can calculate the deviation between the second voltage parameters. According to one embodiment, the processor (120) can calculate the deviation between the second voltage parameters based on the following mathematical expression 1.

[0078]

[0079] (Here, X corresponds to the deviation of the second voltage parameter, corresponds to the second voltage parameter, corresponds to the first voltage parameter, and the time interval T-1 corresponds to the time interval adjacent to the time interval T.)

[0080] For example, when calculating a deviation corresponding to a second time period (T2), the processor (120) can calculate a deviation (X) value based on the first voltage parameter and the second voltage parameter of each of the second time period (T2) and the first time period (T1).

[0081] Here, the processor (120) can calculate a deviation (X) value corresponding to each time interval. If there is a deviation value greater than a preset reference value among the calculated deviation values, the processor (120) can detect that there is a battery cell in which an abnormal voltage behavior occurs due to a voltage inflection phenomenon caused by a tab disconnection among a plurality of battery cells.

[0082] The voltage profile of a battery cell until it enters a resting period after a charge / discharge operation of the battery cell exhibits various behaviors depending on the state of the battery cell. A battery management device (100, see FIG. 1) according to an embodiment disclosed in the present document can detect abnormal voltage behavior due to a tab open defect of a battery cell and abnormal voltage behavior due to a polarization difference. The voltage change due to voltage inflection tends to rise momentarily at the beginning of the resting period, whereas the voltage change due to polarization tends to fall continuously during the resting period. The battery management device (100) can effectively detect momentary voltage changes due to polarization by appropriately dividing the time period in the period where a momentary voltage increase appears and calculating the deviation of the voltage parameter between adjacent time periods.

[0083] FIG. 5 is a flowchart for explaining the operation of a battery management device according to an embodiment disclosed in this document.

[0084] At step S101, the battery management device (100, see FIG. 1) can obtain a voltage profile representing a change in the voltage of each of a plurality of battery cells (11, 12, 13, 14) over time.

[0085] According to one embodiment, the voltage profile may include data representing changes in voltage over time for each of the plurality of battery cells (11, 12, 13, 14) from the point at which the plurality of battery cells (11, 12, 13, 14) are fully charged or fully discharged.

[0086] In step S102, the battery management device (100) can divide the voltage profile into multiple time intervals.

[0087] Here, the battery management device (100) can set the length of each of the multiple time intervals to be the same or different from each other. According to one embodiment, the length of the earliest time interval and / or the earliest time interval among the multiple time intervals may be shorter than the lengths of the other time intervals. However, one embodiment disclosed in this document is not limited to this example, and the length of the earliest time interval and a preset number of time intervals from the earliest time interval may be set in various ways, such as being set to be shorter than the lengths of the other time intervals.

[0088] In step S103, the battery management device (100) can calculate an average voltage, which is an average of the voltages of a plurality of battery cells (11, 12, 13, 14) corresponding to each of a plurality of time periods.

[0089] In step S104, the battery management device (100) can calculate an average rate of change in the average voltage of the plurality of battery cells (11, 12, 13, 14) in each of the plurality of time periods. Here, the average voltage of the plurality of battery cells (11, 12, 13, 14) can correspond to the average voltage calculated based on step S103.

[0090] In step S105, the battery management device (100) can detect an abnormality in a plurality of battery cells (11, 12, 13, 14) based on a deviation between average change rates in adjacent time periods among a plurality of time periods.

[0091] According to one embodiment, the battery management device (100) can calculate the deviation between the average change rates based on the mathematical expression 1 described above, but is not limited thereto.

[0092] According to one embodiment, the battery management device (100) can detect that a battery cell with a disconnected tab exists among a plurality of battery cells (11, 12, 13, 14) when the calculated deviation is greater than a preset reference value.

[0093] FIG. 6 is a drawing for explaining a computing system equipped with a battery management device according to an embodiment disclosed in this document.

[0094] Referring to FIG. 6, the computing system (600) may include an MCU (610), a memory (620), an input / output I / F (630), and a communication I / F (640).

[0095] The MCU (610) may be a processor that executes various programs (e.g., battery cell diagnostic programs, etc.) stored in the memory (620), processes various data for detecting abnormalities in multiple battery cells (11, 12, 13, 14, see FIG. 1) through these programs, and performs the functions of the battery management device (100) described with reference to FIG. 2.

[0096] The memory (620) can store various programs for detecting abnormalities in battery cells. Furthermore, the memory (620) can store various data generated during the process of detecting abnormalities in battery cells, such as information on time interval length, deviation, first and second voltage parameters, etc.

[0097] Such memories (620) may be provided in multiples as needed. The memories (620) may be volatile memories or non-volatile memories. As volatile memories (620), RAM, DRAM, SRAM, etc. may be used. As non-volatile memories (620), ROM, PROM, EAROM, EPROM, EEPROM, flash memories, etc. may be used. The examples of the memories (620) listed above are merely examples and are not limited to these examples.

[0098] The input / output I / F (630) can provide an interface that enables data transmission and reception between an input device (not shown) such as a keyboard, mouse, or touch panel, and an output device (not shown) such as a display and the MCU (610).

[0099] The communication I / F (640) is a component capable of transmitting and receiving various data with the server, and may be any device capable of supporting wired or wireless communication. For example, a program for predicting battery cell deterioration or various data may be transmitted and received from a separately provided external server via the communication I / F (640).

[0100] In this way, the battery cell abnormality detection method according to one embodiment disclosed in this document can be recorded in the memory (620) and executed by the MCU (610).

[0101] In the above, all components constituting the embodiments have been described as being combined or operating in combination as one. However, this is not necessarily limited to such embodiments, and within the scope of the purpose, all components may be selectively combined and operated in one or more combinations. Furthermore, terms such as "include," "comprise," or "have" described above, unless specifically stated to the contrary, imply that the corresponding component may be inherent, and therefore should be interpreted to include other components rather than excluding other components.

[0102] The above description is merely an example of the technical idea disclosed in this document, and those skilled in the art to which the embodiments disclosed in this document pertain may make various modifications and variations without departing from the essential characteristics of the embodiments disclosed in this document.

[0103] Accordingly, the embodiments disclosed in this document are intended to illustrate, rather than limit, the technical concepts disclosed in this document, and the scope of the technical concepts disclosed in this document is not limited by these embodiments. The scope of protection of the technical concepts disclosed in this document should be interpreted by the claims below, and all technical concepts within the equivalent scope should be interpreted as being included within the scope of the rights of this document.

Claims

1. An interface for obtaining a voltage profile representing the change in voltage of each of multiple battery cells over time; and A battery management device comprising a processor that detects whether the plurality of battery cells are abnormal based on a first voltage parameter related to an average voltage of the plurality of battery cells corresponding to each of the plurality of time periods by dividing the voltage profile into a plurality of time periods and a second voltage parameter related to a difference between the first voltage parameters between adjacent time periods among the plurality of time periods.

2. In paragraph 1, The above interface obtains the voltage profile whenever the SoC of the plurality of battery cells reaches a preset threshold value, A battery management device in which the length of the earliest time interval among the above multiple time intervals is shorter than the lengths of the other time intervals.

3. In the second paragraph, the first voltage parameter is A battery management device including data related to an average rate of change in the average voltage of the plurality of battery cells in each of the plurality of time periods.

4. In the third paragraph, the second voltage parameter is A battery management device corresponding to a difference value between first parameters corresponding to each adjacent time period among the above multiple time periods.

5. In the fourth paragraph, the processor, A battery management device that calculates the deviation between the above second voltage parameters based on the following mathematical expression 1. [Mathematical Formula 1] (Here, X corresponds to the deviation between the second voltage parameters, corresponds to the second voltage parameter, corresponds to the first voltage parameter, and the time interval T-1 corresponds to the time interval adjacent to the time interval T.) 6. In the fifth paragraph, the processor, A battery management device that detects that a battery cell with a disconnected tab exists among the plurality of battery cells when the deviation between the second parameters is greater than a preset reference value.

7. A step of obtaining a voltage profile representing the change in voltage of each of a plurality of battery cells over time; A step of dividing the above voltage profile into multiple time intervals; A step of calculating an average voltage of the plurality of battery cells corresponding to each of the plurality of time periods; A step of calculating an average rate of change of the average voltage of the plurality of battery cells in each of the plurality of time periods; and A method for operating a battery management device, comprising: a step of detecting an abnormality of the plurality of battery cells based on a deviation between the average change rates in adjacent time periods among the plurality of time periods.

8. In paragraph 7, A method of operating a battery management device, wherein the voltage profile includes data indicating a change in voltage over time for each of the plurality of battery cells from the point in time when the plurality of battery cells reach a charge completion or discharge completion state.

9. In paragraph 8, An operating method of a battery management device, wherein the length of the earliest time interval among the above multiple time intervals is shorter than the lengths of other time intervals.

10. In the 7th paragraph, the operating method of the battery management device is calculated based on the following mathematical expression 1, wherein the deviation between the average change rates is calculated based on the following mathematical expression 1. [Mathematical Formula 1] (Here, X corresponds to the deviation between the above average rates of change, corresponds to the difference between the average rates of change in adjacent time intervals, corresponds to the above average rate of change, and time point T-1 corresponds to a time point adjacent to time point T.) 11. In the 10th paragraph, the step of detecting an abnormality in the plurality of battery cells is: A method of operating a battery management device, comprising: a step of detecting that a battery cell with a disconnected tab exists among the plurality of battery cells when the deviation is greater than a preset reference value.

Images