Battery management device, battery management method, and medium

Abstract

According to some embodiments, a battery management device comprises: an interface configured to obtain battery data of a battery; and a controller configured to identify the average cell voltage and the lowest cell voltage for a plurality of cell voltages of the battery at each measurement time point on the basis of the battery data, identify a lowest voltage behavior of the battery on the basis of a first profile relating to accumulated values of the average cell voltage up to the current time point and a second profile relating to accumulated values of the lowest cell voltage up to the current time point, and diagnose the state of the battery on the basis of the lowest voltage behavior.

Description

Battery management device, battery management method and medium

[0001] Cross-citation with related applications

[0002] The present application claims the benefit of priority based on Korean Patent Application No. 10-2025-0182015 filed on November 26, 2025 and Korean Patent Application No. 10-2024-0180842 filed on December 6, 2024, and includes all contents disclosed in the documents of said patent applications as part of this specification.

[0003] Technology field

[0004] The embodiments disclosed in this document relate to a battery management device, a battery management method, and a medium.

[0005] Recently, active research and development on secondary batteries has been underway. Here, secondary batteries are rechargeable batteries and can be interpreted to encompass conventional Ni / Cd and Ni / MH batteries, as well as the more recent lithium-ion batteries. Among secondary batteries, lithium-ion batteries can possess higher energy density compared to conventional Ni / Cd and Ni / MH batteries, and because they can be manufactured in a compact and lightweight form factor, they offer high utility as power sources for mobile devices. Recently, their scope of application has expanded to include power sources for electric vehicles, drawing attention as a next-generation energy storage medium.

[0006] Techniques for diagnosing the condition of a battery pack using the voltages of multiple battery cells constituting the pack are being developed. For example, the average voltage of multiple cells and the deviation between each cell voltage can be utilized for condition diagnosis. Considering the amount of data and computation required for condition diagnosis, new methods may be needed to improve diagnostic efficiency.

[0007] One of the objectives of the embodiments disclosed in this document is to provide a battery management device, a battery management method, and a medium capable of diagnosing a battery condition using the lowest cell voltage among a plurality of cell voltages to improve diagnostic efficiency.

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

[0009] According to some embodiments, a battery management device comprises: a memory for storing instructions; and at least one processor for executing said instructions, wherein the at least one processor is configured to acquire battery data of a battery, identify an average cell voltage and a minimum cell voltage for a plurality of cell voltages of the battery at each measurement time based on said battery data, identify a minimum voltage behavior of the battery based on a first profile regarding accumulated values ​​of said average cell voltage up to a current time and a second profile regarding accumulated values ​​of said minimum cell voltage up to a current time, and diagnose the state of the battery based on said minimum voltage behavior.

[0010] According to some embodiments, the at least one processor is configured to calculate a minimum voltage deviation by subtracting the average cell voltage of the first profile from the minimum cell voltage of the second profile at each measurement point, and to identify the minimum voltage behavior based on a plurality of minimum voltage deviations corresponding to a plurality of measurement points.

[0011] According to some embodiments, the at least one processor is configured to apply a moving average filter to the plurality of lowest voltage deviations to calculate a plurality of moving average deviations and to diagnose the state of the battery based on the plurality of moving average deviations.

[0012] According to some embodiments, the moving average filter includes an exponential moving average (EMA) filter that applies a first weight α between 0 and 1 to the current value and a second weight 1-α to the previous value.

[0013] According to some embodiments, the at least one processor is configured to diagnose the state of the battery as defective at the point when the plurality of moving average deviations become smaller than a first threshold.

[0014] According to some embodiments, the at least one processor is configured to diagnose the state of the battery at times after an initial inspection period has elapsed among a plurality of measurement times.

[0015] According to some embodiments, the at least one processor is configured to select a plurality of target timestamps having a minimum cell voltage greater than a second threshold among a plurality of measurement timestamps, and to form the first profile and the second profile based on the values ​​of the average cell voltage and the values ​​of the minimum cell voltage at the plurality of target timestamps.

[0016] According to some embodiments, a battery management method comprises: acquiring battery data of a battery; identifying an average cell voltage and a minimum cell voltage for a plurality of cell voltages of the battery at each measurement point in time based on the battery data; identifying a minimum voltage behavior of the battery based on a first profile regarding the cumulative values ​​of the average cell voltage up to a current point in time and a second profile regarding the cumulative values ​​of the minimum cell voltage up to a current point in time; and diagnosing the state of the battery based on the minimum voltage behavior.

[0017] According to some embodiments, the step of identifying the lowest voltage behavior includes: calculating the lowest voltage deviation by subtracting the average cell voltage of the first profile from the lowest cell voltage of the second profile at each measurement point; and identifying the lowest voltage behavior based on a plurality of lowest voltage deviations corresponding to a plurality of measurement points.

[0018] According to some embodiments, the step of diagnosing the state of the battery comprises: a step of calculating a plurality of moving average deviations by applying a moving average filter to the plurality of lowest voltage deviations; and a step of diagnosing the state of the battery based on the plurality of moving average deviations.

[0019] According to some embodiments, the moving average filter includes an exponential moving average (EMA) filter that applies a first weight α between 0 and 1 to the current value and a second weight 1-α to the previous value.

[0020] According to some embodiments, the step of diagnosing the state of the battery includes diagnosing the state of the battery as defective at the point when the plurality of moving average deviations become smaller than a first threshold.

[0021] According to some embodiments, the step of diagnosing the state of the battery includes diagnosing the state of the battery at points in time after an initial inspection period has elapsed among a plurality of measurement points.

[0022] According to some embodiments, the step of identifying the lowest voltage behavior comprises: selecting a plurality of target timestamps having the lowest cell voltage greater than a second threshold among a plurality of measurement timestamps; and generating the first profile and the second profile based on the values ​​of the average cell voltage and the values ​​of the lowest cell voltage at the plurality of target timestamps.

[0023] According to some embodiments, a computer-readable medium records a program for executing a battery management method on a computer, and the battery management method comprises the steps of: acquiring battery data of a battery; identifying an average cell voltage and a minimum cell voltage for a plurality of cell voltages of the battery at each measurement point based on the battery data; identifying a minimum voltage deviation of the battery based on the difference between the average cell voltage and the minimum cell voltage; and diagnosing the state of the battery based on the minimum voltage deviation.

[0024] According to the embodiments disclosed in this document, a battery management device, a battery management method, and a medium may be provided that can diagnose the battery condition using the lowest cell voltage among a plurality of cell voltages to improve diagnostic efficiency.

[0025] The technical effects according to the embodiments disclosed in this document are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art in accordance with the disclosure of this document.

[0026] FIG. 1 illustrates elements constituting a battery system according to some embodiments.

[0027] FIG. 2 illustrates elements constituting a battery management device according to some embodiments.

[0028] FIG. 3 illustrates a process of diagnosing a battery condition using the lowest cell voltage among a plurality of cell voltages according to some embodiments.

[0029] FIG. 4 illustrates a first profile regarding average cell voltage and a second profile regarding minimum cell voltage according to some embodiments.

[0030] FIG. 5 illustrates the difference between the average cell voltage and the lowest cell voltage according to some embodiments.

[0031] FIG. 6 illustrates a moving average value for the difference between the average cell voltage and the lowest cell voltage according to some embodiments.

[0032] FIG. 7 illustrates a method of excluding the initial section when comparing a diagnostic indicator according to some embodiments with a diagnostic threshold.

[0033] FIG. 8 illustrates steps constituting a battery management method according to some embodiments.

[0034] Hereinafter, embodiments described in this document are described with reference to the accompanying drawings. However, this is not intended to limit the disclosure of this document to specific embodiments and should be understood to include various modifications, equivalents, and / or alternatives to the embodiments described in this document.

[0035] The embodiments of this document and the terms used therein are not intended to limit the technical features described in this document to specific embodiments and should be understood to include various modifications, equivalents, or substitutions of said embodiments. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more of said items unless the relevant context clearly indicates otherwise.

[0036] In this document, each of the phrases such as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B or C,” “at least one of A, B and C,” and “at least one of A, B, or C” may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof. Terms such as “first,” “second,” “first,” “second,” “A,” “B,” “(a),” or “(b)” may be used simply to distinguish a component from another component and, unless specifically stated otherwise, do not limit the components in any other aspect (e.g., importance or order).

[0037] In this document, where it is stated that any (e.g., 1) component is "connected," "coupled," or "joined" to another (e.g., 2) component, with or without the terms "functionally" or "communicationly," or where it is stated that the component is "coupled" or "connected," it means that the component may be connected to the other component directly (e.g., by wire or wirelessly) or indirectly (e.g., through a 3) component.

[0038] Methods according to the various embodiments disclosed in this document may be provided as part of a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a device-readable storage medium (e.g., compact disc read-only memory, CD-ROM) or distributed online (e.g., download or upload) through an application store or directly between two driver devices. In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily created on a device-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or a relay server.

[0039] According to the embodiments disclosed in this document, each component (e.g., module or program) of the components described above may include a singular or multiple entities, and some of the multiple entities may be separated and placed in other components. According to the embodiments disclosed in this document, one or more of the components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Generally or additionally, multiple components (e.g., module or program) may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the components of the multiple components in the same or similar manner as those performed by the corresponding components among the multiple components prior to the integration. According to the embodiments disclosed in this document, operations performed by a module, program, or other component may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

[0040] FIG. 1 illustrates elements constituting a battery system according to some embodiments.

[0041] Referring to FIG. 1, the battery system (100) may include a power device (110), a battery (120), and a battery management device (130). However, it is not limited thereto, and some components may be omitted from the battery system (100) or other general-purpose components may be further included in the battery system (100).

[0042] A power device (110) may be configured to charge or discharge a battery (120). The power device (110) may include a power consuming device and / or a power supply device. The power device (110) may discharge the battery (120) while consuming power, or charge the battery (120) while generating power. According to an embodiment, the power consuming device may include a motor for a mobility device such as an electric vehicle (EV), a hybrid electric vehicle (HEV), or an electric bike. The mobility device may also operate as a power supply device for charging the battery (120). The mobility device may drive a motor using the power of the battery (120) or charge the battery (120) with power generated through regenerative braking. According to an embodiment, the power supply device may include a charge / discharger for charging or discharging the battery (120). The charge / discharger may apply a charging current, a charging voltage, a discharging current, and / or a discharging voltage, etc., to the battery (120) based on a given profile or cycle.

[0043] The battery (120) may include one or more battery packs. The battery pack of the battery (120) may include a plurality of battery modules, and each battery module may include a plurality of battery cells. According to an embodiment, the battery (120) may be mounted on various types of mobility devices.

[0044] The battery management device (130) can perform operations for diagnosing, managing, and / or controlling the battery (120). The battery management device (130) can acquire battery data of the battery (120), diagnose or manage the state of the battery (120) based thereon, and control the output or charging and discharging of the battery (120). According to an embodiment, the battery management device (130) may include a battery management system (BMS) configured with the battery (120) in an on-board manner, and / or an external device remotely positioned with the battery (120) in an off-board manner. The external device may include a charger at a battery charging station, a battery diagnostic device, a cloud computing server, etc.

[0045] The battery system (100) may further include a management server. The management server can manage the management results of the battery management device (130). The management server can exchange data with the battery management device (130) via wired or wireless communication. When a defect in the battery (120) is diagnosed or its lifespan is predicted, the results can be transmitted to the management server and recorded in a database. According to an embodiment, the battery management device (130) can perform diagnostic operations by running battery management software, and the management server can provide update information of the battery management software to the battery diagnostic device (130).

[0046] FIG. 2 illustrates elements constituting a battery management device according to some embodiments.

[0047] Referring to FIG. 2, the battery management device (130) may include an interface (131) and a controller (132). However, it is not limited thereto, and some components may be omitted from the battery management device (130), or other general-purpose components may be further included in the battery management device (130).

[0048] The interface (131) may be configured to acquire battery data of the battery (120). According to an embodiment, the interface (131) may include a communication unit configured to receive battery data and / or a sensor unit configured to measure battery data. According to an embodiment, if the battery management device (130) is implemented in an off-board form, the communication unit may receive battery data in a manner such as wired data communication or wireless data communication. Alternatively, if the battery management device (130) is implemented in an on-board form, the sensor unit may be configured to measure values ​​such as voltage, current, temperature, and resistance from the battery (120). According to an embodiment, the battery data may include charging data related to the charging of the battery (120) and / or discharge data related to the discharging of the battery (120). For example, the charging data and / or discharge data may include current data, voltage data, temperature data, resistance data, capacity data, lifespan data, and / or degradation data.

[0049] The controller (132) may have a structure for executing instructions that implement the operations of the battery management device (130). The controller (132) may be implemented as an array of logic gates or a general-purpose microprocessor for processing various operations, and may be composed of a single processor or multiple processors. For example, the controller (132) may be implemented in at least one form of a microprocessor, CPU, GPU, and AP.

[0050] The controller (132) can operate with memory configured to store various data, instructions, mobile applications, computer programs, etc. The memory may be configured separately from or integrally with the controller (132). The controller (132) can process various operations by executing instructions stored in the memory. For example, the memory may be implemented as a non-volatile device such as ROM, PROM, EPROM, EEPROM, flash memory, PRAM, MRAM, RRAM, FRAM, etc., or as a volatile device such as DRAM, SRAM, SDRAM, PRAM, etc., and may be implemented in the form of an HDD, SSD, SD, Micro-SD, etc., or a combination thereof.

[0051] According to an embodiment, the battery management device (130) may include a memory configured to store instructions and at least one processor configured to execute said instructions. The at least one processor may perform steps for the operation of the battery management device (130) by executing instructions stored in the memory.

[0052] According to the first embodiment, the battery management device (130) may be configured to identify the average cell voltage and the lowest cell voltage for a plurality of cell voltages of the battery (120) at each measurement point based on battery data. The measurement points may follow a preset cycle such as 1 second, 5 seconds, 10 seconds, 30 seconds, 1 hour, 6 hours, 12 hours, 1 day, etc. When the battery management device (130) enters a sleep state based on the non-use time of the battery (120), such as when the battery (120) is mounted on a mobility device, the average cell voltage and the lowest cell voltage may be measured whenever the battery management device (130) is woken up. For example, in the case of an EV, data may be measured whenever operation starts or ends, and the accumulated data may be organized on a daily basis. The average cell voltage may be the average of the plurality of cell voltages, and the lowest cell voltage may be the minimum value of the plurality of cell voltages.

[0053] According to a first embodiment, the battery management device (130) may be configured to identify the lowest voltage behavior of the battery (120) based on a first profile regarding the accumulated values ​​of the average cell voltage up to the current point in time and a second profile regarding the accumulated values ​​of the lowest cell voltage up to the current point in time. Values ​​of the lowest cell voltage for multiple points in time up to the current point in time may form the first profile, and values ​​of the average cell voltage for multiple points in time up to the current point in time may form the second profile. The first profile and the second profile may represent the pattern of variation over time of the average cell voltage and the lowest cell voltage. The lowest voltage behavior may refer to the behavior of the lowest cell voltage when compared to the behavior of the average cell voltage. According to an embodiment, the cell having the lowest voltage at multiple points in time may be the same. According to an embodiment, the cell having the lowest voltage at multiple points in time may be different, and in this case, the lowest cell voltage at each measurement point in time may be the lowest value among the multiple cell voltages, regardless of which cell voltage is the lowest.

[0054] According to the first embodiment, the battery management device (130) may be configured to diagnose the condition of the battery (120) based on the lowest voltage behavior. The lowest voltage behavior may be one of the indicators used to determine whether a defect or abnormality occurs in the battery (120). A defect or abnormality of the battery (120) may be related to lithium deposition, internal short circuit, abnormal degradation, fire occurrence, etc. If the condition of the battery (120) is diagnosed as a defect or abnormality, the controller (132) may perform various additional actions based on this. For example, the battery (120) circuit opening, grounding, output limiting, performance limiting, usage time limiting, etc. may be performed, and warnings or notifications to the user of the battery (120) and / or power device (110) may be performed through the user's registered terminal device.

[0055] According to the first embodiment, the battery management device (130) may be configured to calculate a minimum voltage deviation by subtracting the average cell voltage of the first profile from the minimum cell voltage of the second profile at each measurement point, and to identify a minimum voltage behavior based on a plurality of minimum voltage deviations corresponding to a plurality of measurement points. That is, a plurality of minimum voltage deviations may be calculated at each measurement point as [minimum voltage deviation = minimum cell voltage - average cell voltage], and this may be the difference between the first profile and the second profile. A deviation profile corresponding to the difference between the first profile and the second profile may be identified as the minimum voltage behavior.

[0056] According to a first embodiment, the battery management device (130) may be configured to apply a moving average filter to a plurality of minimum voltage deviations to calculate a plurality of moving average deviations and to diagnose the state of the battery based on the plurality of moving average deviations. When a moving average filter is applied to a deviation profile corresponding to the difference between a first profile and a second profile, a smoother profile may be generated, and based on this, misdiagnosis caused by instantaneous data fluctuations may be prevented. According to another embodiment, for data processing efficiency, instead of applying a moving average filter, a method of diagnosing the state of the battery by directly comparing the deviation profile corresponding to the difference between a first profile and a second profile with a threshold may be utilized.

[0057] According to the first embodiment, the battery management device (130) may include an exponential moving average (EMA) filter in which a moving average filter applies a first weight α between 0 and 1 to a current value and a second weight 1-α to a previous value. According to the EMA filter, the EMA current value (EMA_t) may be calculated based on the EMA previous value (EMA_t-1) and the current value (ΔV_t) of the lowest voltage deviation according to the deviation profile. For example, the first weight α and the second weight 1-α may be 0.05 and 0.95, respectively, and the EMA current value (EMA_t) may be calculated as [EMA_t = 0.05*ΔV_t + 0.95*EMA_t-1]. The weight α value may be adjusted.

[0058] According to the first embodiment, the battery management device (130) may be configured to diagnose the battery's condition as a defective state at a point where a plurality of moving average deviations become smaller than a first threshold. Since the result of applying the moving average filter can be compared with the threshold, the possibility of misdiagnosis may be reduced. For example, if the moving average deviation becomes smaller than the first threshold at a specific point in time, the battery's condition at that point in time may be diagnosed as a low voltage state.

[0059] According to the first embodiment, the battery management device (130) may be configured to diagnose the condition of the battery at points in time after an initial over-inspection period has elapsed among a plurality of measurement points. In the initial period when battery data collection begins, a period may occur in which the moving average deviation is temporarily smaller than the first threshold as the plurality of moving average deviations converge to a normal range. To prevent misdiagnosis, the corresponding period may be excluded from diagnosis. For example, the corresponding period may be determined by the battery's model, specifications, capacity, etc.

[0060] According to a first embodiment, the battery management device (130) may be configured to select a plurality of target points among a plurality of measurement points that have a lowest cell voltage greater than a second threshold, and to form a first profile and a second profile based on the values ​​of the average cell voltage and the lowest cell voltage at the plurality of target points. Data at some of the measurement points may not be considered for battery diagnosis. For example, if the lowest cell voltage at a specific point is less than 3.9 V, the battery data at that point may be excluded from the first profile and the second profile. According to the embodiment, data at a point excluded through filtering may be supplemented through data interpolation, etc.

[0061] According to a second embodiment, the controller (132) may be configured to calculate a first rate of change of average cell voltage according to a first profile and a second rate of change of minimum cell voltage according to a second profile, and to identify minimum voltage behavior based on the difference in the rate of change between the first rate of change and the second rate of change. The difference in the rate of change between the first rate of change and the second rate of change may be a prerequisite for identifying minimum voltage behavior. If the difference in the rate of change deviates from a normal range, this may mean that it is necessary to examine minimum voltage behavior based on the second profile of minimum cell voltage.

[0062] According to a second embodiment, the controller (132) may be configured to calculate a diagnostic indicator of the lowest cell voltage based on a second profile when the difference in the rate of change deviates from the normal range, and to diagnose the condition of the battery (120) based on the diagnostic indicator. The diagnostic indicator may be an indicator showing the pattern of the lowest cell voltage changing over time. The diagnostic indicator may be calculated based on past values ​​of the lowest cell voltage and current values.

[0063] According to a second embodiment, the controller (132) may be configured to calculate the average value of the lowest cell voltage for a plurality of measurement points accumulated up to the present time, and to calculate a diagnostic indicator based on the difference between the average value of the lowest cell voltage and the current value of the lowest cell voltage. For example, if the second profile records the lowest cell voltage on a daily basis, an average value for all values ​​including values ​​from past dates and today's value may be calculated, and the deviation from the average of the lowest cell voltage may be calculated by subtracting today's value from the average value. The deviation from the average may be used to determine whether there is an abnormality or defect in the battery (120) and may be used for calculating the diagnostic indicator. According to the embodiment, if the lowest cell voltage is recorded on a daily basis, the number of data points for the lowest cell voltage may be greater than a threshold number to calculate the deviation from the average. For example, data must be obtained for a period of 3 months, 6 months, 1 year, or other appropriate duration so that the deviation from the average and diagnostic indicators can properly indicate the condition of the battery (120).

[0064] According to a second embodiment, the controller (132) may be configured to calculate a diagnostic indicator based on a moving average value of the difference value and to diagnose the state of the battery (12) by comparing the moving average value with a diagnostic threshold. The difference value between the average value of the lowest cell voltage and the current value of the lowest cell voltage may be the deviation relative to the average mentioned above, and the moving average value of the deviation relative to the average may be the diagnostic indicator. For example, the moving average value may be calculated by applying weights to past values ​​and current values, where the weight for past values ​​may be 0.95 and the weight for current values ​​may be 0.05. If it is confirmed that the diagnostic indicator falls below the diagnostic threshold, the battery (120) may be diagnosed as being in a defective or abnormal state, and if the time when the diagnostic indicator falls below the diagnostic threshold is expected, the expected time of the defective or abnormal state may be estimated. When a defect / abnormality is diagnosed or estimated, the battery management device (130) may perform output / performance limiting, user warning, etc.

[0065] According to the second embodiment, the controller (132) may be configured to compare the moving average value with the diagnostic threshold for points in time after an initial period determined by the specifications of the battery (120). For example, even if the battery (120) is normal, a situation may occur in which the diagnostic indicator or the moving average value is lower than the diagnostic threshold during the initial period of the entire time interval regarding the recording of the second profile. To avoid misdiagnosing this as a defect or abnormality, the initial period may be excluded from the diagnostic target, and the length of the initial period may be determined by the specifications of the battery (120).

[0066] According to a second embodiment, the controller (132) may be configured to form a first profile and a second profile only for measurement points having a lowest cell voltage that exceeds a voltage threshold. For example, the voltage threshold may be determined as a value in the range of 3.5 to 4.0 V, and if the lowest cell voltage is lower than the voltage threshold, the corresponding measurement data may not be included in the first profile and the second profile. By forming the first profile and the second profile using only data when the lowest cell voltage is higher than the voltage threshold, a decrease in diagnostic accuracy can be prevented.

[0067] FIG. 3 illustrates a process of diagnosing a battery condition using the lowest cell voltage among a plurality of cell voltages according to some embodiments.

[0068] Referring to FIG. 3, a flow (300) illustrating a process of diagnosing the battery condition using the lowest cell voltage among a plurality of cell voltages may be illustrated.

[0069] In step (310), voltage data for multiple battery cells can be obtained. In step (320), if the lowest cell voltage is above a voltage threshold of 3.9 V, the data at that point in time can be recorded as a first profile and a second profile. In step (330), the difference in the rate of change can be analyzed to determine the trend of the average cell voltage and the lowest cell voltage.

[0070] In step (340), the difference between the lowest cell voltage and the average cell voltage can be calculated. In step (350), a moving average value for the difference between the lowest cell voltage and the average cell voltage can be calculated, and the weight values ​​for past data and current data can be 0.95 and 0.05, or other appropriate values. In step (360), the battery condition can be diagnosed by comparing the moving average value with a diagnostic threshold.

[0071] FIG. 4 illustrates a first profile regarding average cell voltage and a second profile regarding minimum cell voltage according to some embodiments.

[0072] Referring to FIG. 4, a graph (400) illustrating a first profile regarding average cell voltage and a second profile regarding minimum cell voltage may be shown. In the graph (400), the horizontal axis may represent time, and the vertical axis may represent average cell voltage (PackAverage; 410) and minimum cell voltage (PackMin; 420).

[0073] The rate of change / slope of the average cell voltage (410) and the rate of change / slope of the lowest cell voltage (420) may generally be the same. However, after a certain point in time, the first rate of change (430) of the average cell voltage (410) and the second rate of change (440) of the lowest cell voltage (420) may differ from each other as illustrated. When such a difference occurs between the average cell voltage (410) and the lowest cell voltage (420), the behavior of the lowest voltage of the battery (120) may be analyzed to determine whether the battery (120) is in a defective or abnormal state.

[0074] FIG. 5 illustrates the difference between the average cell voltage and the lowest cell voltage according to some embodiments.

[0075] Referring to FIG. 5, a graph (500) illustrating the difference value (ΔV) between the average cell voltage (410) and the lowest cell voltage (420) may be shown. In the graph (500), the horizontal axis may represent time, and the vertical axis may represent the difference value (ΔV) between the average cell voltage (410) and the lowest cell voltage (420).

[0076] A difference value (ΔV) between the average cell voltage (410) and the lowest cell voltage (420) can be calculated at each of the multiple measurement points, and this may be the lowest voltage deviation relative to the average. The graph (500) may plot multiple lowest voltage deviations corresponding to multiple measurement points on the vertical axis for the measurement point on the horizontal axis. The graph (500) represents a state in which smoothing by a moving average filter, etc., is not applied, and spikes or peaks may appear due to instantaneous changes in the original data.

[0077] FIG. 6 illustrates a moving average value for the difference between the average cell voltage and the lowest cell voltage according to some embodiments.

[0078] Referring to FIG. 6, a graph (600) illustrating a moving average value for the difference (ΔV) between the average cell voltage (410) and the lowest cell voltage (420) may be shown. In the graph (600), the horizontal axis may represent time, and the vertical axis may represent the moving average value (MA).

[0079] The moving average (MA) of the graph (600) can be calculated by applying a moving average filter to multiple lowest voltage deviations of the graph (500). For example, the EMA value can be calculated by applying an exponential moving average (EMA) filter, and, for example, the weights of the EMA filter can be 0.05 and 0.95. In this case, the EMA value (EMA_t) at the current measurement time (t) can be calculated by applying 0.95 to the EMA value (EMA_t-1) at the previous measurement time (t-1) and applying 0.05 to the difference value (ΔV_t) at the current measurement time (t).

[0080] If the moving average value (MA) in the graph (600) becomes smaller than the diagnostic threshold (610), a defect or abnormality of the battery (120) may be diagnosed. For example, the diagnostic threshold (610) may be -7 mV, and different values ​​may be adopted as needed. Alternatively, the diagnostic threshold (610) may be calculated in real time based on the characteristics, specifications, battery data, etc. of the battery (120).

[0081] FIG. 7 illustrates a method of excluding the initial section when comparing a diagnostic indicator according to some embodiments with a diagnostic threshold.

[0082] Referring to FIG. 7, a graph (700) illustrating a method of excluding the initial section when comparing a diagnostic indicator with a diagnostic threshold can be shown. In the graph (700), the horizontal axis may represent time, and the vertical axis may represent the moving average value (MA).

[0083] The battery in graph (700) may differ from the battery in graph (600). As illustrated, the battery in graph (700) may maintain a moving average value (MA) or diagnostic indicator higher than the diagnostic threshold (710) in the latter part, and thus may be diagnosed as being in a normal state. However, over-inspection data (720) may occur in the initial section (730), and it may be necessary to exclude the over-inspection data (720) to prevent unnecessary over-inspection. To this end, the initial section (730) may be excluded at the time of diagnosis, and the length of the initial section (730) may be set based on battery specifications, battery characteristics, etc.

[0084] FIG. 8 illustrates steps constituting a battery management method according to some embodiments.

[0085] Referring to FIG. 8, the battery management method (800) may include steps (810) through (840). However, it is not limited thereto, some steps may be omitted or other general steps may be added, and the steps of the battery management method (800) may be executed in a different order than the illustrated order.

[0086] The battery management method (800) may consist of steps processed sequentially in the battery management device (130). Therefore, even if the details are omitted below, the description of the battery management device (130) above may be equally applicable to the battery management method (800).

[0087] Steps (810) to (840) of the battery management method (800) can be performed by the interface (131) and controller (132) of the battery management device (130).

[0088] In step (810), the battery management device (130) can perform the step of obtaining battery data of the battery.

[0089] In step (820), the battery management device (130) may perform the step of identifying the average cell voltage and the lowest cell voltage for a plurality of cell voltages of the battery at each measurement point based on battery data.

[0090] In step (830), the battery management device (130) may perform the step of identifying the lowest voltage behavior of the battery based on a first profile regarding the accumulated values ​​of the average cell voltage up to the current point in time and a second profile regarding the accumulated values ​​of the lowest cell voltage up to the current point in time.

[0091] In step (840), the battery management device (130) can perform a step of diagnosing the state of the battery based on the lowest voltage behavior.

[0092] According to an embodiment, the battery management method (800) may be implemented in the form of a computer program stored on a computer-readable storage medium. That is, the computer program may include instructions for implementing the battery management method (800), and the instructions of the program may be stored on a computer-readable storage medium. The computer program may include a mobile application.

[0093] According to an embodiment, a computer-readable storage medium may include magnetic media such as a hard disk, a floppy disk, and a magnetic tape, optical media such as a CD-ROM and a DVD, magneto-optical media such as a floptical disk, and a hardware device specifically configured to store and execute computer program instructions such as ROM, RAM, and flash memory. Computer program instructions may include machine code generated by a compiler and high-level language code that can be executed by a computer using an interpreter, etc.

[0094] Terms such as "include," "compose," or "have" as used above, unless specifically stated otherwise, mean that the relevant component may be inherent; therefore, they should be interpreted as allowing for the inclusion of additional components rather than excluding them. All terms, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the embodiments disclosed in this document pertain, unless otherwise defined. Commonly used terms, such as those defined in advance, should be interpreted in accordance with their meaning in the context of the relevant technology and, unless explicitly defined in this document, should not be interpreted in an ideal or overly formal sense.

[0095] The foregoing description is merely an illustrative explanation of the technical concept disclosed in this document, and a person skilled in the art to which the embodiments disclosed in this document pertain can make various modifications and variations within the scope of the essential characteristics of the embodiments disclosed in this document. Accordingly, the embodiments disclosed in this document are intended to explain, not limit, the technical concept of the embodiments disclosed in this document, and the scope of the technical concept disclosed in this document is not limited by these embodiments. The scope of protection of the technical concept disclosed in this document shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of this document.

Claims

1. Memory for storing instructions; and A battery management device comprising at least one processor that executes the above instructions, The above at least one processor acquires battery data of the battery, and Based on the battery data above, the average cell voltage and the lowest cell voltage for a plurality of cell voltages of the battery are identified at each measurement point, and Identifying the lowest voltage behavior of the battery based on a first profile regarding the accumulated values ​​of the average cell voltage up to the current point in time and a second profile regarding the accumulated values ​​of the lowest cell voltage up to the current point in time, and A battery management device configured to diagnose the state of the battery based on the above-mentioned minimum voltage behavior.

2. In Paragraph 1, The above at least one processor calculates the lowest voltage deviation by subtracting the average cell voltage of the first profile from the lowest cell voltage of the second profile at each measurement point, and A battery management device configured to identify the lowest voltage behavior based on multiple lowest voltage deviations corresponding to multiple measurement points.

3. In Paragraph 2, The above at least one processor calculates a plurality of moving average deviations by applying a moving average filter to the plurality of lowest voltage deviations, and A battery management device configured to diagnose the state of the battery based on the plurality of moving average deviations.

4. In Paragraph 3, A battery management device comprising an exponential moving average (EMA) filter, wherein the moving average filter applies a first weight α between 0 and 1 to the current value and a second weight 1-α to the previous value.

5. In Paragraph 3, A battery management device wherein at least one processor is configured to diagnose the state of the battery as defective at the point when the plurality of moving average deviations become smaller than a first threshold.

6. In Paragraph 1, A battery management device wherein at least one processor is configured to diagnose the state of the battery for points in time after an initial inspection period has elapsed among a plurality of measurement points.

7. In Paragraph 1, The above at least one processor selects a plurality of target timestamps having the lowest cell voltage greater than the second threshold among a plurality of measurement timestamps, and A battery management device configured to form the first profile and the second profile based on the values ​​of the average cell voltage and the values ​​of the lowest cell voltage at the plurality of target points.

8. Step of acquiring battery data of the battery; A step of identifying the average cell voltage and the lowest cell voltage for a plurality of cell voltages of the battery at each measurement point based on the battery data above; A step of identifying the lowest voltage behavior of the battery based on a first profile regarding the cumulative values ​​of the average cell voltage up to the current point in time and a second profile regarding the cumulative values ​​of the lowest cell voltage up to the current point in time; and A battery management method comprising the step of diagnosing the state of the battery based on the above-mentioned minimum voltage behavior.

9. In Paragraph 8, The step of identifying the above-mentioned lowest voltage behavior is, A step of calculating the lowest voltage deviation by subtracting the average cell voltage of the first profile from the lowest cell voltage of the second profile at each measurement point; and A battery management method comprising the step of identifying the lowest voltage behavior based on a plurality of lowest voltage deviations corresponding to a plurality of measurement points.

10. In Paragraph 9, The step of diagnosing the condition of the battery above is, A step of calculating a plurality of moving average deviations by applying a moving average filter to the plurality of minimum voltage deviations; and A battery management method comprising the step of diagnosing the state of the battery based on the plurality of moving average deviations.

11. In Paragraph 10, A battery management method comprising an exponential moving average (EMA) filter, wherein the moving average filter applies a first weight α between 0 and 1 to the current value and a second weight 1-α to the previous value.

12. In Paragraph 10, The step of diagnosing the condition of the battery above is, A battery management method comprising the step of diagnosing the state of the battery as defective at the point where the plurality of moving average deviations become smaller than a first threshold.

13. In Paragraph 8, The step of diagnosing the condition of the battery above is, A battery management method comprising the step of diagnosing the state of the battery at points in time after an initial inspection period has elapsed among a plurality of measurement points.

14. In Paragraph 8, The step of identifying the above-mentioned lowest voltage behavior is, A step of selecting a plurality of target timestamps having the lowest cell voltage greater than a second threshold among a plurality of measurement timestamps; and A battery management method comprising the step of generating the first profile and the second profile based on the values ​​of the average cell voltage and the values ​​of the lowest cell voltage at the plurality of target points.

15. In a computer-readable medium storing a program for executing a battery management method on a computer, the battery management method comprises: Step of acquiring battery data of the battery; A step of identifying the average cell voltage and the lowest cell voltage for a plurality of cell voltages of the battery at each measurement point based on the battery data above; A step of identifying the lowest voltage deviation of the battery based on the difference between the average cell voltage and the lowest cell voltage; and A medium comprising the step of diagnosing the state of the battery based on the above minimum voltage deviation.

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