KR20250029654A - Apparatus for managing battery and operating method of the same - Google Patents

Abstract

A battery management device according to an embodiment disclosed in this document may include a voltage acquisition unit that acquires voltages of each of a plurality of battery cells at a predetermined time interval; and a controller that calculates a voltage elevation value related to an amount of voltage change of each of the plurality of battery cells at the predetermined time interval based on the voltage, and determines whether each of the plurality of battery cells is abnormal based on the voltage elevation value.

Description

{APPARATUS FOR MANAGING BATTERY AND OPERATING METHOD OF THE SAME}

Embodiments disclosed in this document relate to a battery management device and a method of operating the same.

Electric vehicles receive electricity from the outside to charge battery cells, and then drive a motor with the voltage charged in the battery cells to obtain power. Battery cells undergo internal deformation and transformation through various charging and discharging during the production and use stages, and their physical and chemical properties change, which can cause internal short circuits, external short circuits, venting due to lithium deposition, or undervoltage defects in which the voltage of the battery cell decreases below a certain level.

If a defect occurs inside a battery cell, the performance of the battery cell may deteriorate, and direct problems may occur in the battery cell, such as an increased risk of ignition due to electrolyte leakage. Therefore, a technology to determine whether a battery cell is abnormal is required.

Generally, a method is known to diagnose battery cell voltage abnormalities by utilizing the deviation of individual battery cell voltages compared to the average voltage of the battery cells. However, this method is vulnerable to noise, and has limitations in that it is impossible to adjust the threshold, which serves as the basis for diagnosing abnormal battery cells, below a certain level, and it cannot detect abnormal battery cell voltages caused by micro-shortages that occur in electric vehicles.

One purpose of the embodiments disclosed in this document is to provide a battery management device and an operating method thereof capable of accurately diagnosing an abnormal battery cell using a voltage elevation value of the battery cell.

One purpose of the embodiments disclosed in this document is to provide a battery management device and an operating method thereof capable of diagnosing a battery cell while reducing memory usage by using a voltage elevation value of the battery cell.

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 from the descriptions below.

A battery management device according to an embodiment disclosed in this document may include a voltage acquisition unit that acquires voltages of each of a plurality of battery cells at a predetermined time interval; and a controller that calculates a voltage elevation value related to an amount of voltage change of each of the plurality of battery cells at the predetermined time interval based on the voltage, and determines whether each of the plurality of battery cells is abnormal based on the voltage elevation value.

According to an embodiment, the controller can calculate a gain value and a loss value with respect to a voltage change amount of each of the plurality of battery cells, and calculate the voltage elevation value based on the gain value and the loss value.

According to an embodiment, the controller can calculate the gain value by adding a value obtained by multiplying the voltage change amount and the maximum value of 0 by a gain constant to the first gain value.

According to an embodiment, the controller can calculate the loss value by adding a value obtained by multiplying the gain constant by the minimum value of the voltage change amount and 0 to the first gain value.

According to an embodiment, the controller can calculate the first gain value by multiplying a gain value calculated at a time preceding the time at which the gain value is calculated by a difference value that is a difference between 1 and the gain constant.

According to an embodiment, the controller may calculate an arithmetic mean of the voltage elevation values of each of the plurality of battery cells in the predetermined time interval, calculate a first deviation between the voltage elevation values of each of the plurality of battery cells and the arithmetic mean, and determine whether each of the battery cells is abnormal based on the first deviation.

According to an embodiment, the controller may calculate a second deviation between the absolute value of the first deviation of each of the plurality of battery cells and a smallest voltage elevation value among the voltage elevation values of each of the plurality of battery cells, and determine whether each of the battery cells is abnormal based on the second deviation.

According to an embodiment, the controller may determine that the battery cell is in an abnormal state if the second deviation is greater than the first threshold value for the predetermined time period.

According to an embodiment, the predetermined time interval may include at least one of a charging interval, a post-charge rest interval, a discharging interval, and a post-discharging rest interval of the battery cell.

A battery management method according to an embodiment disclosed in this document may include a step of calculating a voltage elevation value related to an amount of voltage change of each of the plurality of battery cells in a predetermined time interval based on the voltage of each of the plurality of battery cells in the predetermined time interval; and a step of determining whether each of the plurality of battery cells is abnormal based on the voltage elevation value.

According to an embodiment, the step of calculating the voltage elevation value may include the step of calculating a gain value and a loss value with respect to the voltage change amount of each of the plurality of battery cells; and the step of calculating the voltage elevation value based on the gain value and the loss value.

According to an embodiment, the step of calculating the gain value may include the step of calculating the gain value by adding a value obtained by multiplying the maximum value of the voltage change amount and 0 by a gain constant to the first gain value.

According to an embodiment, the step of calculating the loss value may include the step of calculating the loss value by adding a value obtained by multiplying the minimum value of the voltage change amount and 0 by the gain constant to the first gain value.

According to an embodiment, the step of calculating the gain value and loss value may include the step of calculating the first gain value by multiplying the gain value calculated at a time prior to the time at which the gain value is calculated by a difference value that is a difference between 1 and the gain constant.

According to an embodiment, after the step of calculating the voltage elevation value, the method may further include the step of calculating an arithmetic mean of the voltage elevation values of each of the plurality of battery cells in the predetermined time interval; the step of calculating a first deviation between the voltage elevation values of each of the plurality of battery cells and the arithmetic mean; and the step of determining whether each of the battery cells is abnormal based on the first deviation.

According to an embodiment, after the step of calculating the first deviation, the method may further include a step of calculating a second deviation between the absolute value of the first deviation of each of the plurality of battery cells and a smallest voltage elevation value among the voltage elevation values of each of the plurality of battery cells; and a step of determining whether each of the battery cells is abnormal based on the second deviation.

According to an embodiment, the step of determining whether each of the battery cells is abnormal may include the step of determining the battery cell as abnormal if the second deviation is greater than a first threshold value for the predetermined time period.

According to an embodiment, a battery management method wherein the predetermined time interval includes at least one of a charging interval, a post-charge rest interval, a discharging interval, and a post-discharging rest interval of the battery cell.

A battery management device and its operating method according to an embodiment disclosed in this document can accurately diagnose an abnormal battery cell using the voltage elevation value of the battery cell.

A battery management device and its operating method according to an embodiment disclosed in this document can diagnose a battery cell while reducing memory usage by using a voltage elevation value of the battery cell.

In addition, various effects may be provided that are directly or indirectly identified through this document.

FIG. 1 is a drawing showing a battery pack according to one embodiment disclosed in this document.
FIG. 2 is a block diagram showing the configuration of a battery management device according to one embodiment disclosed in this document.
FIG. 3 is a graph showing the voltage of a battery cell according to one embodiment disclosed in this document.
FIG. 4 is a graph showing voltage elevation values of a battery cell according to one embodiment disclosed in this document.
FIG. 5 is a graph showing a first deviation of a battery cell according to one embodiment disclosed in this document.
FIG. 6 is a graph showing a second deviation of a battery cell according to one embodiment disclosed in this document.
FIGS. 7A to 7C are graphs detailing a second deviation of a battery cell according to one embodiment disclosed in the present document.
FIG. 8 is a flowchart showing the operation of a battery management device according to one embodiment disclosed in this document.
FIG. 9 is a flowchart showing the operation of a battery management device according to one embodiment disclosed in this document.
FIG. 10 is a block diagram showing the hardware configuration of a computing system that implements an operating method of a battery management device according to one embodiment disclosed in this document.

Hereinafter, various embodiments of the present invention will be described with reference to the attached drawings. However, this is not intended to limit the present invention to specific embodiments, but should be understood to include various modifications, equivalents, and/or alternatives of the embodiments of the present invention.

It should be understood that the various embodiments of this document and the terms used herein are not intended to limit the technical features described in this document to specific embodiments, but include various modifications, equivalents, or substitutes of the 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 item, unless the relevant context clearly indicates otherwise.

In this document, the phrases "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" can each include any one of the items listed together in that phrase, or all possible combinations thereof. The terms "first", "second", "first", "second", "A", "B", "(a)", or "(b)" may be used merely to distinguish one component from another, and do not limit the components in any other respect (e.g., importance or order), unless specifically stated otherwise.

In this document, whenever a component (e.g., a first component) is referred to as being “connected,” “coupled,” or “connected,” with or without the terms “functionally” or “communicatively,” or “coupled” or “connected,” it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or via a third component.

According to one embodiment, the method according to various embodiments disclosed in the present document may be provided as included in a computer program product. The computer program product may be traded between a seller and a buyer as a commodity. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., a compact disc read only memory (CD-ROM)), or may be distributed online (e.g., by download or upload) through an application store or directly between two user devices. In the case of online distribution, at least a part of the computer program product may be temporarily stored or temporarily generated in a machine-readable storage medium, such as a memory of a manufacturer's server, a server of an application store, or an intermediary server.

According to various embodiments, each component (e.g., a module or a program) of the above-described components may include a single or multiple entities, and some of the multiple entities may be separately arranged in other components. According to various embodiments, one or more components or operations of the above-described components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, the multiple components (e.g., a module or a program) may be integrated into one component. In such a case, the integrated component may perform one or more functions of each of the multiple components identically or similarly to those performed by the corresponding component of the multiple components before the integration. According to various embodiments, the operations performed by the module, program, or other component may be executed sequentially, in parallel, repeatedly, 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.

FIG. 1 is a drawing showing a battery pack according to one embodiment disclosed in this document.

Referring to FIG. 1, a battery pack (1000) according to one embodiment disclosed in the present document may include a battery module (100), a battery management device (200), and a relay (300). According to various embodiments, the battery module (100) may be a battery cell, in which case the battery pack (1000) may have a cell to pack structure.

In FIG. 1, a single battery module (100) is illustrated, but depending on the embodiment, the battery module (100) may be configured with a plurality of battery modules, and the battery pack (1000) may have a stacked structure of a plurality of battery modules. The battery module (100) may include a plurality of battery cells (110, 120, 130, 140). The plurality of battery cells (110, 120, 130, 140) may include a first battery cell (110), a second battery cell (120), a third battery cell (130), and a fourth battery cell (140). In FIG. 1, the plurality of battery cells is illustrated as being four, but this is not limited thereto, and the battery module (100) may be configured to include n (n is a natural number greater than or equal to 2) battery cells. Additionally, each of the plurality of battery cells (110, 120, 130, 140) may be a cell group or battery bank in which at least two battery cells are connected in parallel.

The battery module (100) can supply power to a target device (not shown). To this end, the battery module (100) can be electrically connected to the target device. Here, the target device can include an electrical, electronic, or mechanical device that operates by receiving power from a battery pack (1000) including a plurality of battery cells (110, 120, 130, 140), and for example, the target device can be, but is not limited to, an electric vehicle (EV) or an energy storage system (ESS).

A plurality of battery cells (110, 120, 130, 140) are basic units of a battery that can be used by charging and discharging electric energy, and may be, but are not limited to, a lithium-ion (Li-ion) battery, a lithium-ion polymer (Li-ion polymer) battery, a nickel-cadmium (Ni-Cd) battery, a nickel-metal hydride (Ni-MH) battery, etc. Meanwhile, in FIG. 1, a case is illustrated where there is one battery module (100), but depending on the embodiment, the battery module (100) may be configured in multiple units.

A battery management system (BMS) (200) can manage and/or control the status and/or operation of a battery module (100). For example, the battery management device (200) can manage and/or control the status and/or operation of a plurality of battery cells (110, 120, 130, 140) included in the battery module (100). The battery management device (200) can manage charging and/or discharging of the battery module (100).

The battery management device (200) can control the operation of the relay (300). For example, the battery management device (200) can short-circuit the relay (300) to supply power to the target device. Additionally, the battery management device (200) can short-circuit the relay (300) when a charging device is connected to the battery pack (1000).

In addition, the battery management device (200) can monitor the voltage, current, temperature, etc. of the battery module (100) and/or each of the plurality of battery cells (110, 120, 130, 140) included in the battery module (100). In addition, for monitoring by the battery management device (200), sensors or various measurement modules not shown may be additionally installed in any location of the battery module (100), a charging/discharging path, or the battery module (100). The battery management device (200) can calculate parameters indicating the state of the battery module (100), for example, SOC (State of Charge) or SOH (State of Health), based on the measured values of the monitored voltage, current, temperature, etc.

The battery management device (200) can manage the status of each of the battery module (100) and/or the plurality of battery cells (110, 120, 130, 140) included in the battery module (100). As the usage period or number of times of the plurality of battery cells (110, 120, 130, 140) increases, various factors such as a decrease in capacity and an increase in internal resistance can change. The battery management device (200) can diagnose an abnormality inside the plurality of battery cells (110, 120, 130, 140) based on data of various factors that change as the battery cells deteriorate.

According to various embodiments, when a battery cell is abnormal due to various causes such as a defect in the production stage, internal deformation and transformation through multiple charging and discharging, or external impact, the voltage change may occur more rapidly and significantly compared to a normal battery cell. Here, the voltage change may include information related to the resistance of the battery cell. Accordingly, when an abnormality such as lithium deposition, short circuit, or short circuit occurs in the battery cell, the resistance of the battery cell may show a different aspect compared to a normal battery cell. In addition, the resistance abnormality may appear as a voltage change of the battery cell.

Accordingly, the battery management device (200) can diagnose a defective battery cell among the plurality of battery cells (110, 120, 130, 140) by comparing voltage data of each of the chargers and dischargers of the plurality of battery cells (110, 120, 130, 140) by utilizing the phenomenon that a battery cell with an internal defect experiences a faster and greater voltage change than a normal battery cell during the charger and/or the idle period.

According to an embodiment, in the case of an abnormal battery cell, a phenomenon occurs in which the voltage changes rapidly in the charge/discharge section and/or the rest section compared to a normal battery cell, and a large voltage elevation may occur compared to the voltage behavior of a normal battery cell. For example, the voltage elevation may be a measure of the amount of voltage change. According to an embodiment, the voltage elevation value may be calculated based on a gain value and a loss value related to the amount of voltage change of each of a plurality of battery cells (110, 120, 130, 140). An operation of the controller (220) calculating the voltage elevation value may be described in detail with reference to FIGS. 3 to 6 described below.

Analyzing the voltage behavior of the plurality of battery cells (110, 120, 130, 140) through the voltage elevation value can analyze the voltage behavior of the plurality of battery cells (110, 120, 130, 140) more accurately than analyzing the voltage behavior through the voltage change amount. For example, the voltage change amount of each of the plurality of battery cells (110, 120, 130, 140) can include not only resistance information related to a defect of the plurality of battery cells (110, 120, 130, 140), but also resistance information related to the resistance of a portion connected to the plurality of battery cells (110, 120, 130, 140) and other components of the battery pack (1000). Therefore, when diagnosing a plurality of battery cells (110, 120, 130, 140) through voltage changes, it may be difficult for the battery management device (200) to accurately detect resistance information related to defects in the plurality of battery cells (110, 120, 130, 140).

In contrast, the voltage elevation values of the plurality of battery cells (110, 120, 130, 140) can more accurately include resistance information related to a defect in the plurality of battery cells (110, 120, 130, 140). Accordingly, it is possible to detect resistance information related to a defect in the plurality of battery cells (110, 120, 130, 140) while minimizing resistance of a portion connected to the plurality of battery cells (110, 120, 130, 140) and resistance information related to other components of the battery pack (1000). That is, when diagnosing an abnormal battery cell through the voltage elevation values, the battery management device (200) can accurately detect information related to resistance related to a defect in the plurality of battery cells (110, 120, 130, 140).

According to an embodiment, the battery management device (200) can calculate voltage elevation values of a plurality of battery cells (110, 120, 130, 140). Accordingly, the battery management device (200) can determine whether an abnormal battery cell exists among the plurality of battery cells (110, 120, 130, 140) using the voltage elevation values.

According to an embodiment, the battery management device (200) can calculate the deviation of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140). The battery management device (200) can use the deviation of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) to determine an abnormal voltage behavior of at least one battery cell among the plurality of battery cells (110, 120, 130, 140) and diagnose the corresponding battery cell.

According to an embodiment, the operation of the battery management device (200) may be performed in various devices such as a server, cloud, charger, or charger/discharger connected to the battery management device (200) or a vehicle equipped with the battery management device (200).

FIG. 2 is a block diagram showing the configuration of a battery management device according to one embodiment disclosed in this document.

Below, the configuration of the battery management device (200) is specifically described with reference to FIG. 2.

Referring to FIG. 2, the battery management device (200) may include a voltage acquisition unit (210) and a controller (220). However, the present invention is not limited thereto, and some components may be omitted from the battery management device (200), and other general-purpose components may be further included in the battery management device (200).

The voltage acquisition unit (210) can acquire the voltage of each of the plurality of battery cells (110, 120, 130, 140). The voltage acquisition unit (210) can acquire the voltage of each of the plurality of battery cells (110, 120, 130, 140) per unit time. According to one embodiment, the voltage acquisition unit (210) can continuously acquire data related to voltage rise and fall in the charging section, the post-charge rest section, the discharging section, and/or the post-discharging rest section of the plurality of battery cells (110, 120, 130, 140). According to an embodiment, the voltage acquisition unit (210) can include a voltage monitoring circuit or sensor.

The controller (220) can control the operations of the battery management device (200). In addition, the controller (220) can manage each of the plurality of battery cells (110, 120, 130, 140). According to an embodiment, the controller (220) can determine whether each of the plurality of battery cells (110, 120, 130, 140) is abnormal and manage the status based on the voltages of the plurality of battery cells (110, 120, 130, 140) obtained from the voltage obtaining unit (210).

The controller (220) may have a structure for executing commands that implement operations of the battery management device (200). The controller (220) may be implemented as an array of multiple logic gates for processing various operations or as a general-purpose microprocessor, and may be composed of a single processor or multiple processors. For example, the controller (220) may be implemented in the form of at least one of a microprocessor, a CPU, a GPU, and an AP.

The controller (220) may be configured separately from or integrally with a memory and/or storage configured to temporarily store data or commands, and may process various operations by executing commands stored in the memory and/or storage. The memory and/or storage may store various data, commands, mobile applications, computer programs, etc. For example, the memory and/or storage may be implemented as a non-volatile device such as a ROM, a PROM, an EPROM, an EEPROM, a flash memory, a PRAM, a MRAM, a RRAM, a FRAM, etc., or a volatile device such as a DRAM, a SRAM, a SDRAM, a PRAM, a RRAM, a FeRAM, etc., and may be implemented in the form of a HDD, an SSD, an SD, a Micro-SD, etc., or in the form of a combination thereof.

The controller (220) of the battery management device (200) can manage each of the plurality of battery cells (110, 120, 130, 140) and diagnose the status of each of the plurality of battery cells (110, 120, 130, 140) by analyzing voltage data of the charge/discharge section and/or the rest section. In addition, if it is determined as a result of the diagnosis that there is an abnormality in the battery cell, the controller (220) can provide information on the abnormal battery cell to the user. For example, the controller (220) can provide information on the abnormal battery cell to the user terminal through a communication circuit (not shown), and can also provide information on the abnormal battery cell through a display equipped in a vehicle or a charger.

FIG. 3 is a graph showing the voltage of a battery cell according to one embodiment disclosed in this document.

Referring to FIG. 3, the controller (220) may acquire time series data of voltages of each of the plurality of battery cells (110, 120, 130, 140) based on voltage data of the plurality of battery cells (110, 120, 130, 140) acquired from the voltage acquisition unit (210) for each unit time. According to an embodiment, the voltage data of the plurality of battery cells (110, 120, 130, 140) may be acquired at a predetermined time interval. For example, the voltage data may be a voltage acquired at a charging interval, a rest interval after charging, a discharging interval, and/or a rest interval after discharging of each of the plurality of battery cells (110, 120, 130, 140).

The controller (220) can generate a graph (e.g., voltage graph) representing a voltage change of each of the plurality of battery cells (110, 120, 130, 140) based on the voltage of each of the plurality of battery cells (110, 120, 130, 140) per unit time. According to an embodiment, the voltage graph may be a graph related to the voltage of each of the plurality of battery cells (110, 120, 130, 140) with respect to time. For example, the x-axis of the voltage graph may be time (unit: seconds), and the y-axis may be voltage (unit: volts).

According to an embodiment, the slope of the voltage graph of each of the plurality of battery cells (110, 120, 130, 140) may include resistance information. Here, factors affecting the resistance of the battery cell may include, for example, when a battery cell defect such as lithium deposition, short circuit, or disconnection occurs, when the resistance of a portion connected to the battery cell is measured together, or when the resistance of another component of the battery pack (1000) is measured. Therefore, the slope of the voltage graph of each of the plurality of battery cells (110, 120, 130, 140) may exhibit abnormal behavior compared to the slope of a normal battery cell due to the resistance of the portion connected to the battery cell or the resistance of another component of the battery pack (1000), not due to a battery cell defect. Hereinafter, an operation in which the controller (220) diagnoses an abnormality of a battery cell through a voltage elevation value of the battery cell is described.

FIG. 4 is a graph showing voltage elevation values of a battery cell according to one embodiment disclosed in this document.

Referring to FIG. 4, the controller (220) can continuously calculate the elevation values of each of the plurality of battery cells (110, 120, 130, 140) per unit time. According to an embodiment, the controller (220) can calculate time series data of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) based on the voltage data of the plurality of battery cells (110, 120, 130, 140). The voltage elevation values of the plurality of battery cells (110, 120, 130, 140) can be calculated from voltages obtained in the charging section, the resting section after charging, the discharging section, and/or the resting section after discharging of each of the plurality of battery cells (110, 120, 130, 140). Here, the voltage elevation value can be a single measure related to the amount of voltage change.

In an embodiment, the graph of the voltage elevation values may be a graph related to the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) with respect to time. For example, the x-axis of the graph of the voltage elevation values may be time (unit: seconds), and the y-axis may be voltage elevation values (unit: volts).

The controller (220) can determine a faulty battery cell based on the voltage elevation value rather than the voltage change amount in order to accurately detect a battery cell defect. As described above in FIG. 3, when the controller (220) diagnoses a faulty battery cell using the voltage change amount data, there may be a problem in that the battery cell may be diagnosed as faulty even when the battery cell is not actually faulty. This is because the voltage change amount data includes not only information related to the resistance of the battery cell, but also information related to the resistance of the part connected to the battery cell and/or the resistance of other components of the battery pack (1000). In contrast, when the controller (220) diagnoses a faulty battery cell based on the voltage elevation value data, the influence of information related to the resistance of the part connected to the battery cell and/or the resistance of other components of the battery pack (1000) can be reduced while accurately analyzing information related to the resistance of the battery cell.

According to an embodiment, the controller (220) can calculate a gain value (Gain) and a loss value (Loss) regarding the voltage change amount of each of the plurality of battery cells (110, 120, 130, 140). And the controller (220) can calculate a voltage elevation value based on the calculated gain value (Gain) and loss value (Loss).

According to an embodiment, the gain value (Gain, hereinafter, G) may be a value related to an amount of increase in the voltage change amount at a second time (t2) with respect to the voltage change amount of each of the plurality of battery cells (110, 120, 130, 140) at a first time (t1). Here, the first time (t1) may be a time earlier than the second time (t2). That is, the gain value (G) may be a value included in the increase amount of the elevation value at the second time (t2) compared to the first time (t1). Accordingly, the controller (220) may calculate the gain value (G _t2 ) at the second time (t2) based on the gain value (G _t1 ) and the voltage change amount (V _t2 -V _t1 ) calculated at the first time (t1). The voltage change (V _t2 -V _t1 ) may be the difference between the voltage value of each of the plurality of battery cells (110, 120, 130, 140) at a first time (t1) and the voltage value of each of the plurality of battery cells (110, 120, 130, 140) at a second time (t2).

According to an embodiment, the controller (220) can calculate the first gain value (G1) based on the gain value (G _t1 ) calculated at the first time (t1). And, the controller (220) can calculate the gain value (G t2 ) at the second time (t2) based on the first gain value (G1) and the voltage change amount (V _t2 -V _t1 ).

The first gain value (G1) may be a reference value that serves as a reference for calculating an increase or decrease in the voltage elevation value of each of the plurality of battery cells (110, 120, 130, 140). According to an embodiment, the controller (220) may calculate the first gain value (G1) by multiplying the gain value (G _t1 ) calculated at the first time (t1) by a difference value (1-k) that is a difference between 1 and the gain constant (k).

The controller (220) can determine the value of the gain constant (k) to compensate for the elevation value. Here, the gain constant (k) can be a predetermined constant with respect to the plurality of battery cells (110, 120, 130, 140). For example, the gain constant (k) can be a predetermined constant according to the system design requirements. According to an embodiment, the gain constant (k) can be different for each battery module (100) or for each battery pack (1000), and can have a value between 0 and 1.

According to an embodiment, the controller (220) can calculate the gain value (G t2 ) at the second time (t2) by adding a value obtained by multiplying the voltage change amount (V _t2 -V _t1 ) by the gain constant (k) to the calculated first gain value ( _G1 ). According to an embodiment, the controller (220) can calculate the gain value (G t2 ) by adding a value obtained by multiplying a larger value between the voltage change amount (V _t2 -V _t1 ) and 0 by the gain constant (k) to the calculated first gain value ( _G1 ). Here, the controller (220) can multiply the maximum value between the voltage change amount (V _t2 -V _t1 ) and 0 by the gain constant (k) so that the gain value (G _t2 ) is always calculated to be equal to or greater than the first gain value (G1). In another aspect, the controller (220) can calculate the gain value (G _t2 ) within a range in which the gain value (G _t2 ) does not become smaller than the first gain value (G1).

According to an embodiment, the controller (220) can calculate a gain value (G _t2 ) for a voltage change amount based on the following [Mathematical Formula 1].

[Mathematical formula 1]

G _t2 = (1-k)*G _t1 + k*max((V _t2 -V _t1 ),0)

In the above-described [Mathematical Formula 1], G _t1 may represent a gain value calculated at a first time (t1), G _t2 may represent a gain value calculated at a second time (t2), k may represent a gain constant, max may represent a maximum value function, V _t1 may represent a voltage at the first time (t1), and V _t2 may represent a voltage at the second time (t2).

In addition, [Mathematical Formula 1] can be simply expressed using the first gain value (G1) as in the following [Mathematical Formula 2].

[Mathematical formula 2]

G _t2 = G1 + k*max((V _t2 -V _t1 ),0)

According to an embodiment, the loss value (Loss, hereinafter, L) may be a value related to the degree of decrease in the amount of change in voltage at a second time (t2) with respect to the amount of change in voltage of each of the plurality of battery cells (110, 120, 130, 140) at a first time (t1). Here, the first time (t1) may be a time earlier than the second time (t2). In other words, the loss value (L) may be a value that offsets the amount of increase in the elevation value at the second time (t2) compared to the first time (t1).

Accordingly, the controller (220) can calculate the loss value (L _t2 ) at the second time (t2) based on the gain value (G _t1 ) and the voltage change amount (V _t2 -V _t1 ) calculated at the first time (t1). The voltage change amount (V _t2 -V _t1 ) can be the difference between the voltage value of each of the plurality of battery cells (110, 120, 130, 140) at the second time (t2) and the voltage value of each of the plurality of battery cells (110, 120, 130, 140) at the first time (t1).

According to an embodiment, the controller (220) can calculate the first gain value (G1) based on the gain value (G _t1 ) calculated at the first time (t1). In addition, the controller (220) can calculate the loss value (L _t2 ) at the second time (t2) based on the first gain value (G1) and the voltage change amount (V _t2 -V _t1 ). The content of calculating the first gain value (G1) by the controller (220) is the same as the content described above, and therefore is not described again herein.

According to an embodiment, the controller (220) can calculate the loss value (L t2 ) at the second time (t2) by adding a value obtained by multiplying the voltage change amount (V _t2 -V _t1 ) by the gain constant (k) to the calculated first gain value (G1). According to an embodiment, the controller (220) can calculate the loss value (L _t2 ) by adding a value obtained by multiplying a smaller value between the voltage change amount (V _t2 -V _t1 ) and 0 by the gain constant (k) to the calculated first gain value ( _G1 ). Here, the controller (220) can multiply the minimum value between the voltage change amount (V _t2 -V _t1 ) and 0 by the gain constant (k) so that the loss value (L _t2 ) is always calculated to be equal to or smaller than the first gain value (G1). In another aspect, the controller (220) can calculate the loss value (L _t2 ) within a range in which the loss value (L _t2 ) does not become greater than the first gain value (G1).

According to an embodiment, the controller (220) can calculate a loss value (Lt2) for a voltage change amount based on the following [Mathematical Formula 3].

[Mathematical formula 3]

L _t2 = (1-k)*G _t1 + k*min((V _t2 -V _t1 ),0)

In the above-described [Mathematical Formula 3], G _t1 may represent a gain value calculated at a first time (t1), L _t2 may represent a loss value calculated at a second time (t2), k may represent a gain constant, min may represent a minimum value function, V _t1 may represent a voltage at a first time (t1), and V _t2 may represent a voltage at a second time (t2).

In addition, [Mathematical expression 3] can be simply expressed using the first gain value (G1) as in the following [Mathematical expression 4].

[Mathematical Formula 4]

L _t2 = G1 + k*min((V _t2 -V _t1 ),0)

The controller (220) can calculate the elevation value based on the gain value (G) and the loss value (L) described above. According to an embodiment, the controller (220) can calculate the elevation value by adding the loss value (L) to the gain value (G). The calculated elevation value can reflect the weight of the gain and loss for the amount of change in voltage of each of the plurality of battery cells (110, 120, 130, 140) better than the amount of change in voltage. In addition, since the gain value (G) and the loss value (L) constituting the elevation value are both calculated based on the first gain value (G1), the elevation value can reflect information related to the defects of the plurality of battery cells (110, 120, 130, 140) more accurately than the amount of change in voltage.

FIG. 5 is a graph showing a first deviation of a battery cell according to one embodiment disclosed in this document.

Referring to FIG. 5, the controller (220) can calculate a deviation between voltage elevation values based on the voltage elevation values of each of a plurality of battery cells (110, 120, 130, 140).

According to an embodiment, the controller (220) may continuously calculate a first deviation (D1) of voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) per unit time, and generate a graph representing a change in the first deviation (D1) of voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140). The deviation of the voltage elevation values of the plurality of battery cells (110, 120, 130, 140) may be calculated from a voltage obtained in a charging section, a resting section after charging, a discharging section, and/or a resting section after discharging of each of the plurality of battery cells (110, 120, 130, 140).

According to an embodiment, the x-axis of the first deviation (D1) graph of the voltage elevation value may be time (unit: seconds), and the y-axis may be the voltage elevation value (unit: volt).

According to an embodiment, the controller (220) can calculate a first deviation (D1) which is a difference value of the elevation values of each of the plurality of battery cells (110, 120, 130, 140) with respect to the arithmetic mean value of the elevation values of the plurality of battery cells (110, 120, 130, 140) at a specific time.

And, the controller (220) can diagnose each of the plurality of battery cells (110, 120, 130, 140) based on the calculated first deviation (D1). For example, the controller (220) can determine whether each of the plurality of battery cells (110, 120, 130, 140) is abnormal based on the calculated first deviation (D1).

The controller (220) can determine whether an abnormal battery cell exists among a plurality of battery cells (110, 120, 130, 140) by using the characteristic that the elevation value of an abnormal battery cell has a large deviation compared to the elevation value of a normal battery cell. Accordingly, the controller (220) can diagnose an abnormal voltage behavior of at least one battery cell among the plurality of battery cells (110, 120, 130, 140) by using the deviation (D1) of the elevation value of each of the plurality of battery cells (110, 120, 130, 140).

FIG. 6 is a graph showing a second deviation of a battery cell according to one embodiment disclosed in this document.

Referring to FIG. 6, the controller (220) can calculate a second deviation (D2) of voltage elevation values based on a first deviation (D1) of voltage elevation values of each of a plurality of battery cells (110, 120, 130, 140).

According to an embodiment, the controller (220) may continuously calculate a second deviation (D2) of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) per unit time, and generate a graph representing a change in the second deviation (D2) of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140). The deviation of the voltage elevation values of the plurality of battery cells (110, 120, 130, 140) may be calculated from a voltage obtained in a charging section, a resting section after charging, a discharging section, and/or a resting section after discharging of each of the plurality of battery cells (110, 120, 130, 140).

According to an embodiment, the x-axis of the second deviation graph of the voltage elevation value may be time (unit: seconds), and the y-axis may be the voltage elevation value (unit: volt).

According to an embodiment, the controller (220) can produce second deviation (D2) data by amplifying and/or processing first deviation (D1) data of voltage elevation values of each of a plurality of battery cells (110, 120, 130, 140).

According to an embodiment, the controller (220) can calculate the size of the first deviation (D1) of each of the plurality of battery cells (110, 120, 130, 140) at a specific time. For example, the controller (220) can calculate the absolute value of the first deviation (D1) of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140).

And according to an embodiment, the controller (220) can calculate a deviation between the absolute value of the first deviation (D1) and the voltage elevation value of a specific battery cell among the plurality of battery cells (110, 120, 130, 140) at a specific time. For example, the controller (220) can calculate the second deviation (D2) based on the voltage elevation value of a battery cell (e.g., 110) having the smallest voltage elevation value among the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140). According to an embodiment, the second deviation (D2) can be calculated from the difference between the absolute value of the first deviation (D1) of each of the plurality of battery cells (110, 120, 130, 140) and the smallest voltage elevation value among the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140). Through the second deviation (D2), the controller (220) can more clearly diagnose an abnormal battery cell having a large deviation compared to the elevation value of a normal battery cell.

According to an embodiment, the controller (220) can diagnose each of the plurality of battery cells (110, 120, 130, 140) based on the calculated second deviation (D2). For example, the controller (220) can determine whether each of the plurality of battery cells (110, 120, 130, 140) is abnormal based on the calculated second deviation (D2).

The controller (220) can more accurately determine a battery cell with a large deviation in elevation value, i.e., an abnormal battery cell, based on the second deviation (D2). Therefore, the controller (220) can effectively diagnose an abnormal voltage behavior of at least one battery cell among the plurality of battery cells (110, 120, 130, 140) by using the second deviation (D2) of the elevation value of each of the plurality of battery cells (110, 120, 130, 140).

FIGS. 7A to 7C are graphs detailing a second deviation of a battery cell according to one embodiment disclosed in the present document.

FIGS. 7A to 7C are enlarged views of three specific time sections of the second deviation (D2) graph of the voltage elevation value of FIG. 6. Specifically, FIG. 7A is a second deviation (D2) graph of the voltage elevation value of each of a plurality of battery cells (110, 120, 130, 140) in a predetermined time section (e.g., between 7,600 seconds and 9,000 seconds). FIG. 7B is a second deviation (D2) graph of the voltage elevation value of each of a plurality of battery cells (110, 120, 130, 140) in a predetermined time section (e.g., between 32,400 seconds and 34,000 seconds). FIG. 7c is a second deviation (D2) graph of voltage elevation values of each of a plurality of battery cells (110, 120, 130, 140) over a predetermined time interval (e.g., between 57,200 seconds and 58,600 seconds).

Referring to FIGS. 7a, 7b, and 7c, the controller (220) can compare the second deviation (D2) of each voltage elevation value of the plurality of battery cells (110, 120, 130, 140) with a first threshold value. The controller (220) can compare the second deviation (D2) of each voltage elevation value of the plurality of battery cells (110, 120, 130, 140) with the first threshold value in a unit time of a predetermined time interval.

Here, the first threshold value may be defined as a reference value for diagnosing an abnormal battery cell. According to an embodiment, the first threshold value may be determined by the specifications at the time of design of the plurality of battery cells (110, 120, 130, 140). For example, the first threshold value may be changed according to the size and characteristics of the voltage elevation value data of each of the plurality of battery cells (110, 120, 130, 140).

And the controller (220) can diagnose the status of each of the plurality of battery cells (110, 120, 130, 140) based on the comparison result of the second deviation (D2) and the first threshold value. For example, the controller (220) can determine whether the second deviation (D2) of each of the plurality of battery cells (110, 120, 130, 140) exceeds the first threshold value. That is, the first threshold value can be defined as a criterion indicating how much the data contradicts a specific statistical model.

According to an embodiment, the controller (220) may determine a battery cell among a plurality of battery cells (110, 120, 130, 140) in which a second deviation (D2) exceeds a first threshold value as a battery cell in which an abnormal behavior of a voltage elevation value has occurred. According to an embodiment, when the second deviation (D2) of the voltage elevation value of a specific battery cell is greater than the first threshold value, the controller (220) may determine the specific battery cell to be in an abnormal state. Conversely, when the second deviation (D2) of the voltage elevation value of a specific battery cell is less than the first threshold value, the controller (220) may determine the specific battery cell to be in a normal state.

Referring back to FIG. 7A, the controller (220) may compare the second deviation (D2) of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) with a first threshold value per unit time. Here, the first threshold value may be 0.04. Then, the controller (220) may determine that a battery cell among the plurality of battery cells (110, 120, 130, 140) in which the second deviation (D2) exceeds the first threshold value is a battery cell in which an abnormal behavior of the voltage elevation value has occurred. For example, the controller (220) may determine that a battery cell (120, 130, 140) in which the second deviation (D2) of the voltage elevation value is greater than the first threshold value (e.g., 0.04) is in an abnormal state around 8,300 seconds.

Referring to FIG. 7b, the controller (220) can determine that the battery cell (120) in which the second deviation (D2) of the voltage elevation value is greater than the first threshold value (e.g., 0.04) is in an abnormal state around 33,100 seconds.

Referring to FIG. 7c, the controller (220) can determine that the battery cell (120, 130) in which the second deviation (D2) of the voltage elevation value is greater than the first threshold value (e.g., 0.04) is in an abnormal state around 57,800 seconds.

FIG. 8 is a flowchart showing the operation of a battery management device according to one embodiment disclosed in this document.

According to an embodiment, the operations illustrated in FIG. 8 can be performed through the battery management device (200) of FIG. 2.

Referring to FIG. 8, in operation S101, the voltage acquisition unit (210) can acquire the voltage of each of the plurality of batteries. According to an embodiment, the plurality of batteries may be a plurality of battery cells (110, 120, 130, 140).

In operation S102, the controller (220) can calculate the voltage elevation value of each of the plurality of battery cells (110, 120, 130, 140) based on the acquired voltage. The controller (220) can calculate the voltage elevation value based on the gain value and loss value regarding the voltage change amount.

In operation S103, the controller (220) can calculate a first deviation (D1) of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) based on the voltage elevation values.

In operation S104, the controller (220) can calculate a second deviation (D2) of the voltage elevation value of each of the plurality of battery cells (110, 120, 130, 140) based on the first deviation (D1) of the voltage elevation value.

In operation S105, the controller (220) can compare the second deviation (D2) of the voltage elevation values of each of the plurality of battery cells (110, 120, 130, 140) with the first threshold value.

In operation S106, the controller (220) can determine whether each of the plurality of battery cells (110, 120, 130, 140) is abnormal. The controller (220) can determine a battery cell (e.g., 120) in which the second deviation (D2) is greater than the first threshold value as an abnormal battery cell.

FIG. 9 is a flowchart showing the operation of a battery management device according to one embodiment disclosed in this document.

According to an embodiment, the operations illustrated in FIG. 9 can be performed through the battery management device (200) of FIG. 2.

Referring to FIG. 9, in operation S201, the voltage acquisition unit (210) can acquire the voltage of each of the plurality of batteries. According to an embodiment, the plurality of batteries may be a plurality of battery cells (110, 120, 130, 140).

In operation S202, the controller (220) can calculate the gain and loss values of each of the plurality of battery cells (110, 120, 130, 140) based on the acquired voltage.

In operation S203, the controller (220) can calculate the voltage elevation value of each of the plurality of battery cells (110, 120, 130, 140) based on the gain value and the loss value.

FIG. 10 is a block diagram showing the hardware configuration of a computing system that implements an operating method of a battery management device according to one embodiment disclosed in this document.

Referring to FIG. 10, a computing system (2000) according to one embodiment disclosed in the present document may include an MCU (2100), a memory (2200), an input/output I/F (2300), and a communication I/F (2400).

The MCU (2100) may be a processor that executes various programs (e.g., a battery voltage analysis program) stored in the memory (2200), processes various data from these programs, and performs the functions of the battery management device (200) shown in FIG. 1 described above.

The memory (2200) can store various programs related to the operation of the battery management device (200). In addition, the memory (2200) can store operation data of the battery management device (200).

These memories (2200) may be provided in multiple numbers as needed. The memories (2200) may be volatile memories or nonvolatile memories. As volatile memories (2200), RAM, DRAM, SRAM, etc. may be used. As nonvolatile memories (2200), ROM, PROM, EAROM, EPROM, EEPROM, flash memories, etc. may be used. The examples of the memories (2200) listed above are merely examples and are not limited to these examples.

The input/output I/F (2300) can provide an interface that enables data to be transmitted and received 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 (2100).

The communication I/F (2400) is a configuration that can transmit and receive various data with the server, and may be various devices that can support wired or wireless communication. For example, programs for resistance measurement and abnormality diagnosis or various data can be transmitted and received from a separately provided external server through the communication I/F (2400).

In the above, even though all the components constituting the embodiments disclosed in this document have been described as being combined or operating in combination as one, the embodiments disclosed in this document are not necessarily limited to these embodiments. That is, within the scope of the purpose of the embodiments disclosed in this document, all of the components may be selectively combined and operated in one or more combinations.

In addition, the terms "include," "comprise," or "have" as described above, unless otherwise specifically stated, mean that the corresponding component can be included, and therefore should be interpreted as including other components rather than excluding other components. All terms, including technical or scientific terms, unless otherwise defined, 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. Commonly used terms, such as terms defined in the dictionary, should be interpreted as being consistent with the contextual meaning of the relevant technology, and shall not be interpreted in an idealistic or overly formal sense, unless explicitly defined in this document.

The foregoing disclosure outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art will readily appreciate that the present disclosure can be used as a basis for designing or modifying other structures to perform the same purposes or achieve the same advantages of the embodiments introduced herein. Furthermore, those skilled in the art will recognize that such equivalent constructions do not depart from the scope of the present disclosure, and that various changes, substitutions, and modifications can be made herein without departing from the scope of the present disclosure.

1000: Battery Pack
100: Battery module
110: 1st battery cell
120: Second battery cell
130: 3rd battery cell
140: 4th battery cell
200: Battery management device
210: Voltage acquisition unit
220: Controller
300: Relay
2000: Computing Systems
2100: MCU
2200: Memory
2300: Input/Output I/F
2400: Communication I/F

Claims (18)

A voltage acquisition unit for acquiring the voltage of each of a plurality of battery cells at a predetermined time interval; and
Based on the voltage, a voltage elevation value related to the voltage change amount of each of the plurality of battery cells in the predetermined time interval is calculated,
A battery management device including a controller that determines whether each of the plurality of battery cells is abnormal based on the voltage elevation value. In claim 1,
The above controller,
Calculate the gain and loss values for the voltage change amount of each of the plurality of battery cells,
A battery management device that calculates the voltage elevation value based on the above gain and loss values. In claim 2,
The above controller,
A battery management device that calculates the gain value by adding a value obtained by multiplying the maximum value of the voltage change amount and 0 by a gain constant to the first gain value. In claim 3,
The above controller,
A battery management device that calculates the loss value by adding a value obtained by multiplying the gain constant by the minimum value between the voltage change amount and 0 to the first gain value. In claim 4,
The above controller,
A battery management device that calculates the first gain value by multiplying the gain value calculated at a time preceding the time at which the above gain value is calculated by a difference value which is the difference between 1 and the gain constant. In claim 1,
The above controller,
Calculating the arithmetic mean of the voltage elevation values of each of the plurality of battery cells during the above predetermined time interval,
Calculating the first deviation between the voltage elevation value of each of the plurality of battery cells and the arithmetic mean value,
A battery management device that determines whether each battery cell is abnormal based on the first deviation. In claim 6,
The above controller,
Calculating a second deviation between the absolute value of the first deviation of each of the plurality of battery cells and the smallest voltage elevation value among the voltage elevation values of each of the plurality of battery cells,
A battery management device that determines whether each battery cell is abnormal based on the second deviation. In claim 7,
The above controller,
A battery management device that determines that the battery cell is in an abnormal state when the second deviation is greater than the first threshold value for the predetermined time period. In claim 1,
A battery management device wherein the predetermined time interval includes at least one of a charging interval, a post-charge rest interval, a discharging interval, and a post-discharging rest interval of the battery cell. A step of calculating a voltage elevation value related to the amount of voltage change of each of the plurality of battery cells in a predetermined time interval based on the voltage of each of the plurality of battery cells in the predetermined time interval; and
A battery management method comprising a step of determining whether each of the plurality of battery cells is abnormal based on the voltage elevation value. In claim 10,
The step of calculating the above voltage elevation value is:
A step of calculating a gain value and a loss value for each of the voltage changes of the plurality of battery cells; and
A battery management method comprising a step of calculating the voltage elevation value based on the gain value and the loss value. In claim 11,
The step of calculating the above gain value is:
A battery management method comprising the step of calculating the gain value by adding a value obtained by multiplying the maximum value of the voltage change amount and 0 by a gain constant to the first gain value. In claim 12,
The steps for calculating the above loss value are:
A battery management method comprising a step of calculating the loss value by adding a value obtained by multiplying the gain constant by the minimum value of the voltage change amount and 0 to the first gain value. In claim 13,
The step of calculating the above gain and loss values is:
A battery management method comprising the step of calculating the first gain value by multiplying the gain value calculated at a time preceding the time at which the gain value is calculated by a difference value which is the difference between 1 and the gain constant. In claim 10,
After the step of calculating the above voltage elevation value,
A step of calculating an arithmetic mean of the voltage elevation values of each of the plurality of battery cells during the predetermined time interval;
A step of calculating a first deviation between the voltage elevation value of each of the plurality of battery cells and the arithmetic mean value; and
A battery management method further comprising a step of determining whether each of the battery cells is abnormal based on the first deviation. In claim 15,
After the step of calculating the first deviation,
A step of calculating a second deviation between the absolute value of the first deviation of each of the plurality of battery cells and the smallest voltage elevation value among the voltage elevation values of each of the plurality of battery cells; and
A battery management method further comprising a step of determining whether each of the battery cells is abnormal based on the second deviation. In claim 16,
The step of determining whether each of the above battery cells is abnormal is as follows:
A battery management method comprising the step of determining the battery cell as being in an abnormal state if the second deviation is greater than the first threshold value for the predetermined time interval. In claim 10,
A battery management method wherein the predetermined time interval includes at least one of a charging interval, a post-charge rest interval, a discharging interval, and a post-discharging rest interval of the battery cell.