Battery management apparatus and battery management method

Abstract

A battery management device disclosed in this document comprises: a sensor unit for measuring voltages and currents of a plurality of battery cells; and a control unit for generating accumulated voltage deviation data in which deviations between voltages of the plurality of battery cells are accumulated, determining SOCs of the plurality of battery cells based on the current, generating accumulated SOC deviation data in which deviations between SOCs of the plurality of battery cells are accumulated, and determining SOC of the plurality of battery cells based on the accumulated SOC deviation data. And determining a cause of failure of the plurality of battery cells based on the accumulated voltage deviation data and the accumulated SOC deviation data.

Description

Technical Field

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2023-0121004, filed with the Korean Intellectual Property Office on September 12, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The embodiments disclosed herein relate to battery management devices and battery management methods for diagnosing the state of a battery. Background Technology

[0004] In recent years, research and development of rechargeable batteries have been actively underway. Here, rechargeable batteries refer to batteries that can be charged and discharged, including all traditional nickel (Ni) / cadmium (Cd) batteries, nickel / metal hydride (MH) batteries, and more recently, lithium-ion batteries. Among these rechargeable batteries, lithium-ion batteries have a higher energy density compared to traditional Ni / Cd and Ni / MH batteries. Furthermore, lithium-ion batteries can be manufactured to be small and lightweight, making them suitable for use as power sources in mobile devices. In addition, as the application of lithium-ion batteries expands to powering electric vehicles, they are gaining attention as a next-generation energy storage medium.

[0005] Defective battery cells, such as those with broken connectors or lithium deposition, can cause safety issues during battery use, thus necessitating research into defective battery cell detection algorithms. Traditionally, a simple method based on deviations in voltage and state of charge (SOC) has been used to diagnose battery abnormalities. However, this traditional method relies on high reference values ​​for these deviations to prevent over-diagnosis, leading to diagnostic delays and costly replacement of components due to the inability to determine the cause of the battery abnormality. Summary of the Invention

[0006] Technical issues

[0007] According to the embodiments disclosed herein, a battery management device and battery management method are provided that can easily identify the causes of voltage deviation and SOC deviation using cumulative deviation data.

[0008] The technical problems of the embodiments disclosed herein are not limited to those described above. Other unmentioned technical problems can be clearly understood by those skilled in the art through the following description.

[0009] Technical solution

[0010] A battery management device according to one embodiment includes: a sensor unit configured to measure the voltage and current of a plurality of battery cells; and a control unit configured to generate voltage deviation accumulation data obtained by accumulating the deviation between the voltages of the plurality of battery cells, determine the state of charge (SOC) of the plurality of battery cells based on the current, generate SOC deviation accumulation data obtained by accumulating the deviation between the SOCs of the plurality of battery cells, and determine the cause of defects in the plurality of battery cells based on the voltage deviation accumulation data and the SOC deviation accumulation data.

[0011] The control unit can also be configured to determine the time required for the increase of voltage deviation and SOC deviation based on accumulated voltage deviation data and accumulated SOC deviation data, and to identify the cause of deviation corresponding to the time required for the increase as the cause of defect in multiple battery cells.

[0012] The control unit can also be configured to determine the deviation counts of voltage deviation and SOC deviation based on accumulated voltage deviation data and accumulated SOC deviation data, and to identify the deviation causes corresponding to the deviation counts as the defect causes of multiple battery cells.

[0013] The control unit can also be configured to determine the maximum deviation of voltage deviation and SOC deviation based on accumulated voltage deviation data and accumulated SOC deviation data, and to identify the deviation cause corresponding to the maximum deviation as the defect cause of multiple battery cells.

[0014] The control unit can also be configured to determine the required time from the time of the maximum deviation to the time of the next maximum deviation based on the voltage deviation accumulation data and the SOC deviation accumulation data, and to identify the deviation cause corresponding to the required time as the defect cause of multiple battery cells.

[0015] The control unit can also be configured to determine the rate of occurrence of the maximum deviation based on the required time, and to identify the cause of the deviation corresponding to the rate of occurrence of the maximum deviation as the cause of defect in multiple battery cells.

[0016] The control unit can also be configured to reset the accumulated data based on the voltage deviation accumulated data and the SOC deviation accumulated data being within the normal range.

[0017] The control unit can also be configured to store the maximum deviation up to the reset time based on the cumulative data being reset, wherein the previously stored maximum deviation is compared with the maximum deviation up to the reset time, and the larger value between them is stored.

[0018] The battery management method according to the embodiments includes the following steps: measuring the voltage and current of a plurality of battery cells; generating voltage deviation accumulation data obtained by accumulating the deviation between the voltages of the plurality of battery cells; determining the state of charge (SOC) of the plurality of battery cells based on the current; generating SOC deviation accumulation data obtained by accumulating the deviation between the SOCs of the plurality of battery cells; and determining the cause of defects in the plurality of battery cells based on the voltage deviation accumulation data and the SOC deviation accumulation data.

[0019] The steps to determine the cause of defects in multiple battery cells may include the following steps: determining the time required for the increase of voltage deviation and SOC deviation based on accumulated voltage deviation data and accumulated SOC deviation data, and identifying the deviation cause corresponding to the required increase time as the cause of defects in multiple battery cells.

[0020] The steps for determining the cause of defects in multiple battery cells may include the following steps: determining deviation counts of voltage deviation and SOC deviation based on accumulated voltage deviation data and accumulated SOC deviation data; and identifying the deviation causes corresponding to the deviation counts as the causes of defects in multiple battery cells.

[0021] The steps to determine the cause of defects in multiple battery cells may include the following steps: determining the maximum deviation of voltage deviation and SOC deviation based on cumulative voltage deviation data and cumulative SOC deviation data; and determining the deviation cause corresponding to the maximum deviation as the cause of defects in multiple battery cells.

[0022] The steps for determining the cause of defects in multiple battery cells may include the following steps: determining the time required from the time of the maximum deviation to the time of the next maximum deviation based on accumulated voltage deviation data and accumulated SOC deviation data; and identifying the deviation cause corresponding to the required time as the cause of defects in multiple battery cells.

[0023] The steps to determine the cause of defects in multiple battery cells may include the following steps: determining the rate of occurrence of the maximum deviation based on the required time; and identifying the cause of deviation corresponding to the rate of occurrence of the maximum deviation as the cause of defects in the multiple battery cells.

[0024] Battery management methods may also include the following steps: resetting accumulated data based on voltage deviation accumulated data and SOC deviation accumulated data being within the normal range.

[0025] The battery management method may also include the following steps: storing the maximum deviation up to the reset time based on the cumulative data being reset, wherein the previously stored maximum deviation is compared with the maximum deviation up to the reset time, and the larger value between them is stored.

[0026] Beneficial effects

[0027] Using the battery management device according to the embodiment, the causes of voltage or SOC deviations can be classified based on deviation accumulation data, thereby reducing cost losses by replacing the causative component instead of replacing all components related to the battery abnormality.

[0028] Using the battery management device according to the embodiment, the cause of voltage or SOC deviation can be analyzed to perform balancing without replacing components, thereby reducing deviation and thus reducing the time and cost required for cause analysis. Attached Figure Description

[0029] Figure 1 This is a block diagram illustrating the configuration of a general battery system including a battery management device according to an embodiment.

[0030] Figure 2 This is a block diagram illustrating the configuration of a battery management device according to an embodiment.

[0031] Figure 3 The data types stored in the memory of a battery management device according to an embodiment are schematically shown.

[0032] Figure 4 The process of determining the cause of battery defects according to a battery management device according to an embodiment is illustrated schematically.

[0033] Figure 5 The state changes of the battery management device according to an embodiment are shown.

[0034] Figure 6 The values ​​stored in a battery management device according to an embodiment are shown.

[0035] Figures 7 to 10 This is a graph showing the accumulated deviation data obtained in the battery management device according to the embodiment.

[0036] Figure 11 This is a flowchart of a battery management method according to an implementation method.

[0037] Figure 12 It is shown continuously Figure 11 The flowchart of the battery management method. Detailed Implementation

[0038] In the following, various embodiments disclosed herein will be described in detail with reference to the accompanying drawings. In this document, the same reference numerals will be used for the same components in the drawings, and the same components will not be described again.

[0039] The specific structural or functional descriptions of the various embodiments disclosed herein are merely illustrative examples for the purpose of describing the embodiments. The various embodiments disclosed herein can be implemented in various forms and should not be construed as being limited to the embodiments described herein.

[0040] As used in various embodiments, the terms "first," "second," "first," "second," etc., may modify various components regardless of their order and / or importance, and do not limit these components. For example, a first component may be named a second component without departing from the scope of the embodiments disclosed herein, and similarly, a second component may be named a first component.

[0041] The terminology used herein is for the purpose of describing specific exemplary embodiments only and may not be intended to limit the scope of other exemplary embodiments. It should be understood that, unless the context clearly specifies otherwise, the singular form includes plural references.

[0042] All terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments disclosed herein pertain. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having the same or similar meaning as they have in the context of the relevant field, and unless explicitly defined herein, these terms will not be interpreted in an idealized or overly formal sense. In some cases, the terms defined herein should not be construed as excluding the embodiments disclosed herein.

[0043] Figure 1 This is a block diagram illustrating the configuration of a general battery system including a battery management device according to various embodiments.

[0044] Specifically, Figure 1 A battery system 10 and an advanced controller 20 included in an advanced system are schematically shown according to an embodiment disclosed herein.

[0045] like Figure 1 As shown, the battery system 10 may include multiple battery modules 12, sensor units 14, switching units 16, and battery management devices 1. The battery system 10 may include multiple battery modules 12, sensor units 14, switching units 16, and battery management devices 1.

[0046] Multiple battery modules 12 may include at least one rechargeable battery cell 13. The battery cell 13 may include a positive electrode, a positive electrode material, a negative electrode, a negative electrode material, a separator, a polymer, and a casing. In this configuration, the multiple battery modules 12 may be connected in series or in parallel.

[0047] The sensor unit 14 may include a current sensor 2, a voltage sensor 3, and a temperature sensor (not shown).

[0048] The current sensor 2 can detect the current used in determining the SOC of the battery cell 13.

[0049] The current sensor 2 may include any component for generating a signal corresponding to the magnitude of the charging current, and may be installed on the charging and discharging path in which the charging and discharging current flows in the battery.

[0050] The current sensor 2 can measure the battery current flowing in the battery, i.e., the charging current and the discharging current, and send the measurement results to the battery management device 1. According to an embodiment, the current sensor 2 can measure the battery current at predetermined intervals during a charging cycle for charging the battery using power from an external device or a discharging cycle for discharging the battery, and send the measurement results to the battery management device 1.

[0051] Voltage sensor 3 can be connected in parallel with the battery and configured to detect the battery voltage across opposite ends of the battery and generate a voltage signal indicating the detected battery voltage.

[0052] A temperature sensor can be configured to measure battery temperature and generate a temperature signal indicating the measured battery temperature. The temperature sensor can be disposed within the housing to measure a temperature close to the actual temperature of the battery. For example, the temperature sensor can be attached to the surface of at least one battery cell included in a cell assembly and detect the surface temperature of the battery cell as the battery temperature.

[0053] A temperature sensor can be configured to measure the external temperature at a predetermined location spaced apart from the battery and generate a temperature signal indicating the measured external temperature. The temperature sensor can be positioned at a predetermined location outside the housing where heat exchange occurs between the battery and the atmosphere. According to embodiments, the temperature sensor can be implemented by combining one, two, or more known temperature sensing elements (such as thermocouples, thermistors, bimetallic sensors, etc.). Sensor unit 14 can detect the current flowing in the battery system 10. In this case, a detection signal can be sent to the battery management device 1.

[0054] Although Figure 1 The sensor unit 14 is connected between the positive terminal of the battery cell 13 and the switching unit 16, but Figure 1 The connections between components shown are examples and are not limited to these.

[0055] The switching unit 16 can be connected in series to the positive (+) terminal or the negative (-) terminal of the battery module 12 to control the charging and discharging current of the battery module 12. For example, for the switching unit 16, depending on the specifications of the battery system 10, at least one relay, magnetic contactor, etc. can be used.

[0056] The battery management device 1 can perform control and management by monitoring the voltage, current, temperature, etc. of the battery system 10 to prevent overcharging and over-discharging, and may include, for example, a BMS.

[0057] The battery management device 1, which serves as an interface for receiving measured values ​​of the various parameters mentioned above, may include multiple terminals and circuitry connected to the multiple terminals to process input values. Furthermore, the battery management device 1 can control the switching unit 16, such as a relay or contactor, to turn on / off, and can be connected to the battery modules 12 to monitor the status of each battery module 12.

[0058] The battery management device 1 can receive temperature data, voltage data and current data from the sensor unit 14 to obtain battery status information and diagnose the battery status.

[0059] The advanced controller 20 can send control signals to the battery management device 1 for controlling the battery module 12. Therefore, the operation of the battery management device 1 can be controlled based on the control signals applied from the advanced controller 20. Furthermore, the battery module 12 can be a component included in an energy storage system (ESS). In this case, the advanced controller 20 can be a battery pack control unit (BBMS) including multiple battery systems 10, or an ESS control unit for controlling the entire ESS including multiple battery packs. However, the battery system 10 is not limited to this purpose.

[0060] Figure 2 This is a block diagram illustrating the configuration of a battery management device according to an embodiment.

[0061] Reference Figure 2 According to the embodiment, the battery management device 1 may include a control unit 100 and a communication unit 200. The control unit 100 includes at least one processor 110 and a memory 120, and the battery management device 1 can diagnose the battery by communicating with an external device 4 via the communication unit 200.

[0062] According to an embodiment, the external device 4 communicating with the battery management device 1 may include a user terminal that transmits diagnostic results from the battery management device 1.

[0063] Specifically, when the external device 4 is a user terminal, the control unit 100 of the battery management device 1 can send the battery diagnostic results to the user terminal so that the user can check the diagnostic results. In this case, the user terminal may include, but is not limited to, a personal computer (PC), a terminal, a portable phone, a smartphone, a handheld device, a wearable device, etc.

[0064] When external device 4 is a server device, the server device can be implemented using various computing devices such as workstations, clouds, data drives, data stations, etc. The server device can be implemented as one or more server devices that are physically or logically separated based on functions, their detailed configurations, data, etc., and can send and receive data through communication between server devices, and can process the sent and received data.

[0065] The battery management device 1 according to the embodiment can refer to any electronic device including processor 110 and memory 120, and can be installed in a vehicle for operation. Each component of the battery management device 1 will be described in detail below.

[0066] The communication unit 200 may include a wireless communication unit 210 and a wired communication unit 220 for communicating with the external device 4. The communication unit 200 may send and receive programs or various data, such as those for characteristic calculations, classification, and lifespan estimation of battery cells, to a separately provided external server.

[0067] The wireless communication unit 210 may include at least one of a short-range communication module or a long-range communication module.

[0068] The short-range communication module can communicate with an external device 4 located adjacent to the battery management device 1 using a short-range communication method. Here, the short-range communication module can use one of the following communication methods: Bluetooth, Bluetooth Low Energy (BLE), Infrared Data Association (IrDA), Zigbee, WiFi, WiFi Direct, Ultra Wideband (UWB), or Near Field Communication (NFC).

[0069] The remote communication module may include communication modules that perform various types of remote communication, and may include a mobile communication unit. The mobile communication unit can transmit and receive radio signals from at least one of a base station, an external terminal, or an external device 4 via a mobile communication network. The remote communication module can communicate with the external device 4 or other electronic devices via a nearby access point (AP). The AP can connect the local area network (LAN) to which the battery management device 1 is connected to the wide area network (WAN) to which the communication server is connected. Therefore, the battery management device 1 and the external device 4 can communicate with each other via the WAN connection to the communication server.

[0070] The wired communication unit 220 can access a wired communication network and communicate with the external device 4 through the wired communication network. For example, the wired communication unit 220 can access the wired communication network via Ethernet (IEEE 802.3, technical standard), access the wired communication network via CAN communication, and send data to and receive data from the external device 4 through the wired communication network.

[0071] The battery management device 1 according to the embodiment may include an input / output interface (not shown). An interface may be provided to allow data to be sent and received via connection to an input device (not shown) such as a keyboard, mouse, touch panel, etc., an output device such as a display (not shown), and a processor 110.

[0072] The memory 120 can store various information required for driving the battery management device 1. Specifically, the memory 120 can store the operating system and programs required for driving the battery management device 1, or store the data required for driving the battery control device 1.

[0073] Specifically, the memory 120 can store various programs related to the characteristic calculation, classification, and lifespan estimation of battery cells. Furthermore, the memory 120 can store various data for each battery cell, such as voltage, current, and characteristic data.

[0074] The memory 120 can also store the SOC and SOH of the battery cell 13 estimated by the processor 110.

[0075] The memory 120 may include volatile memory 120 such as static random access memory (S-RAM) and dynamic random access memory (D-RAM) for temporary data storage. The memory 120 may also include non-volatile memory 120 such as read-only memory (ROM), erasable programmable read-only memory (EPROM), and electrically erasable programmable read-only memory (EEPROM) for long-term data storage.

[0076] The processor 110 can control the battery management device 1 as a whole by outputting control signals. The processor 110 may include one CPU or graphics processing unit (GPU) or multiple CPUs or GPUs. In this case, the processor 110 may be implemented as an array of multiple logic gates, or it may be implemented as a combination of a general-purpose microprocessor 110 and a memory 120 storing programs that can be executed on the microprocessor 110.

[0077] The memory 120 and processor 110 may be included in the control unit 100 that controls the above components to determine whether a fault has occurred in the battery cell.

[0078] Specifically, the control unit 100 can generate voltage deviation accumulation data obtained by accumulating the deviation between the voltages measured in multiple battery cells, and generate SOC deviation accumulation data obtained by accumulating the deviation between the SOCs of multiple battery cells.

[0079] Therefore, the control unit 100 can determine the SOC of the multiple battery cells based on the current measured in the multiple battery cells.

[0080] The control unit 100 can determine the time required for the increase of voltage deviation and SOC deviation based on the accumulated voltage deviation data and the accumulated SOC deviation data, and identify the cause of deviation corresponding to the required increase time as the cause of defect in multiple battery cells.

[0081] The control unit 100 can determine the number of times the voltage deviation and SOC deviation occur based on the accumulated voltage deviation data and the accumulated SOC deviation data, and determine the cause of the deviation corresponding to the number of times the deviation occurs as the defect cause of multiple battery cells.

[0082] The control unit 100 can determine the maximum deviation of voltage deviation and SOC deviation based on voltage deviation accumulation data and SOC deviation accumulation data, and determine the deviation cause corresponding to the maximum deviation as the defect cause of multiple battery cells.

[0083] The control unit 100 can determine the required time from the time of the maximum deviation to the time of the next maximum deviation based on the voltage deviation accumulation data and the SOC deviation accumulation data, and determine the deviation cause corresponding to the required time as the defect cause of multiple battery cells.

[0084] The control unit 100 can determine the maximum deviation occurrence rate based on the required time, and identify the deviation cause corresponding to the maximum deviation occurrence rate as the defect cause of multiple battery cells. In this way, the control unit 100 can match various factors with the deviation cause to determine the defect cause of the battery cell.

[0085] The control unit 100 can also reset the accumulated data based on the voltage deviation accumulated data and SOC deviation accumulated data being within the normal range. Furthermore, it can store the maximum deviation up to the reset time based on the reset of the accumulated data, compare the maximum deviation up to the reset time with the previously stored maximum deviation, and store the larger value. Therefore, the control unit 100 can continuously update the maximum deviation to determine the cause of the deviation.

[0086] Thus, the battery management device according to the embodiment can diagnose whether a defect has occurred in the battery cell by using the accumulated voltage deviation data and accumulated SOC deviation data of the battery cell, thereby significantly improving the reliability of the diagnosis.

[0087] Figure 3 The data types stored in the memory 120 of the battery management device according to an embodiment are schematically shown.

[0088] Reference Figure 3 The control unit 100 can receive current and voltage from multiple battery cells from the sensor unit 14. The processor 110 of the control unit 100 can calculate the state of charge (SOC) of the battery cells based on the received current, and the SOC calculation can be performed using the current integration method or the open-circuit voltage (OCV) measurement method.

[0089] The processor 110 can generate deviation data a, which includes voltage deviation data and SOC deviation data, based on the received voltage and the calculated SOC. The processor 110 can identify the battery usage pattern and generate cumulative deviation data b, which includes cumulative voltage deviation data and cumulative SOC deviation data.

[0090] Therefore, the battery management device according to the embodiment can store both deviation data a and deviation accumulation data b in the memory 120. That is, unlike conventional techniques that only store deviation data a in the memory 120, deviation data a and deviation accumulation data b regarding deviation increase / decrease can be stored in the storage unit.

[0091] Therefore, the processor 110 of the control unit 100 can match the battery usage pattern with the deviation accumulation trend by using the deviation accumulation data b based on the battery usage pattern, thereby determining the cause of the battery defect. The control unit 100 can then send the cause of the battery defect to an external device 4, including a user terminal and a server device.

[0092] Figure 4 The process of determining the cause of battery defects according to a battery management device according to an embodiment is illustrated schematically.

[0093] Reference Figure 4 According to the embodiment, the control unit 100 of the battery management device can receive the battery voltage value and battery current value at a specific time point from the voltage sensor 3 and the current sensor 2, and determine the SOC of the battery cell based on the current value.

[0094] Subsequently, the voltage deviation accumulation data generation unit 101 of the control unit 100 can accumulate the difference between the voltages of the battery cells to generate voltage deviation accumulation data. In addition, the SOC deviation accumulation data generation unit 102 of the control unit 100 can generate SOC deviation accumulation data by accumulating the difference between a preset reference SOC and the calculated SOC of the battery cells.

[0095] The voltage deviation Vdev can be determined by subtracting the minimum voltage Vmin from the maximum voltage Vmax in the battery cell, or by subtracting the minimum voltage Vmin from the median voltage Vmedian in the battery cell.

[0096] Although Figure 4 The diagram shows that voltage deviation cumulative data is generated first, followed by SOC deviation cumulative data, but the order is not restricted. Thus, SOC deviation cumulative data can be generated first, followed by voltage deviation cumulative data, or both can be generated simultaneously in parallel.

[0097] Subsequently, the deviation cause explanation unit 103 of the control unit 100 can determine the cause of the deviation based on the accumulated SOC deviation data and the accumulated voltage deviation data. Specifically, the control unit 100 can generate and visualize the accumulated data according to the battery usage pattern, interpret the visualization graph, and determine the cause of the deviation. This will be explained in the following reference. Figure 5 Please describe in detail.

[0098] The defect cause determination unit 104 of the control unit 100 can determine the defect cause corresponding to the determined deviation cause. That is, when the deviation cause is determined, the control unit 100 can match the deviation cause with the pre-classified defect causes and send the defect cause to the external device 4.

[0099] For example, when the deviation in the accumulated SOC deviation data during battery charging decreases, the control unit 100 can determine that the deviation has been reduced through cell balancing, and the control unit 100 can determine that the cell balancing function is working properly.

[0100] In another example, when the deviation in the accumulated SOC deviation data during battery charging remains constant, the control unit 100 can determine that the deviation cannot be reduced by cell balancing, and the control unit 100 can determine that there is a problem with the cell balancing function.

[0101] Therefore, the control unit 100 can determine that the deviation is caused by the failure to perform the cell balancing operation and identify the classified defect cause as a cell balancing failure.

[0102] Subsequently, the control unit 100 can send a signal or message about a cell balance fault to the external device 4, and the user can diagnose the battery based on the signal or message about the cell balance fault sent to the external device 4.

[0103] Figure 5 The state changes of the battery management device according to an embodiment are shown. Figure 6 The values ​​stored based on state changes in a battery management device according to an embodiment are shown.

[0104] Reference Figure 5 The state of a battery management device can change according to the battery usage mode and can be divided into an initial state (a), a charging state (b), an operating state (c), and an end state (d). That is, the initial state (a) can refer to the standby state before the battery is used; the charging state (b) can refer to the state where the battery is connected to the power source and is charging; the operating state (c) can refer to the state where the battery is discharging due to being used; and the end state (d) can refer to the state where the charging state (b) or the operating state (d) has ended.

[0105] For example, refer to Figure 5 The solid line portion indicates that the state of the battery management device, depending on the battery usage mode, can change from the initial state (a) to the operating state (c), from the operating state (c) to the charging state (b), from the charging state (b) to the operating state (c), from the operating state (c) to the end state (d), and from the end state (d) back to the initial state (a), thus forming a cycle.

[0106] Next, refer to Figure 6 According to Figure 5 The state changes of the battery management device determine the value stored in memory 120.

[0107] First, when the state of the battery management device changes from the initial state to the operating state (a), the control unit 100 can store the voltage deviation accumulation data acc_Vdev_r, the SOC deviation accumulation data acc_SOCdev_r, and the accumulation time data Tr as storage value e in the memory 120.

[0108] Referring to the storage value details f, the cumulative voltage deviation data acc_Vdev_r can be determined as the value obtained by adding the voltage deviation change ΔVdev_r to the immediately preceding cumulative voltage deviation data acc_Vdev_r (acc_Vdev_r = acc_Vdev_r + ΔVdev_r). The cumulative SOC deviation data acc_SOCdev_r can be determined as the value obtained by adding the SOC deviation change ΔSOCdev_r to the immediately preceding cumulative SOC deviation data acc_SOCdev_r (acc_SOCdev_r = acc_SOCdev_r + ΔSOCdev_r). The cumulative time data Tr can be determined as the value obtained by adding the cumulative time change ΔTr to the immediately preceding cumulative time data Tr (Tr = Tr + ΔTr).

[0109] Referring to detail g, the voltage deviation change △Vdev_r can be represented by subtracting the voltage deviation Vdev_end at the end of the immediately preceding stage from the initial voltage deviation Vdev_init (△Vdev_r = Vdev_init - Vdev_end). The SOC deviation change △SOCdev_r can be represented by subtracting the SOC deviation SOCdev_end at the end of the immediately preceding stage from the initial SOC deviation SOCdev_init (△SOCdev_r = SOCdev_init - SOCdev_end). The cumulative time change △Tr can be represented by subtracting the cumulative time Tend at the end of the immediately preceding stage from the initial cumulative time T_init (△Tr = Tinit - Tend).

[0110] Next, when the state of the battery management device changes from the operating state to the charging state (b), the control unit 100 can store the voltage deviation accumulation data acc_Vdev_d, the SOC deviation accumulation data acc_SOCdev_d, and the accumulation time data Td as storage value e in the memory 120.

[0111] Referring to the storage value details f, the cumulative voltage deviation data acc_Vdev_d can be determined as the value obtained by adding the voltage deviation change ΔVdev_d to the immediately preceding cumulative voltage deviation data acc_Vdev_d (acc_Vdev_d = acc_Vdev_d + ΔVdev_d). The cumulative SOC deviation data acc_SOCdev_d can be determined as the value obtained by adding the SOC deviation change ΔSOCdev_d to the immediately preceding cumulative SOC deviation data acc_SOCdev_d (acc_SOCdev_d = acc_SOCdev_d + ΔSOCdev_d). The cumulative time data Td can be determined as the value obtained by adding the cumulative time change ΔTd to the immediately preceding cumulative time data Td (Td = Td + ΔTd).

[0112] Referring to detail g, the voltage deviation change △Vdev_d can be represented by subtracting the voltage deviation Vdev_init of the immediate preceding stage in the initial state from the voltage deviation Vdev_d in the operating state (△Vdev_d = Vdev_d - Vdev_init). The SOC deviation change △SOCdev_d can be represented by subtracting the SOC deviation SOCdev_init of the immediately preceding stage in the initial state from the SOC deviation SOCdev_d in the operating state (△SOCdev_d = SOCdev_d - SOCdev_init). The cumulative time change △Td can be represented by subtracting the cumulative time Tinit of the immediately preceding stage in the initial state from the cumulative time T_d in the operating state (△Td = Td - Tinit).

[0113] Next, when the state of the battery management device changes from the charging state to the operating state (c), the control unit 100 can store the voltage deviation accumulation data acc_Vdev_c, the SOC deviation accumulation data acc_SOCdev_c, and the accumulation time data Tc as storage value e in the memory 120.

[0114] Referring to the storage value details f, the cumulative voltage deviation data acc_Vdev_c can be determined as the value obtained by adding the voltage deviation change ΔVdev_c to the immediately preceding cumulative voltage deviation data acc_Vdev_c (acc_Vdev_c = acc_Vdev_c + ΔVdev_c). The cumulative SOC deviation data acc_SOCdev_c can be determined as the value obtained by adding the SOC deviation change ΔSOCdev_c to the immediately preceding cumulative SOC deviation data acc_SOCdev_c (acc_SOCdev_c = acc_SOCdev_c + ΔSOCdev_c). The cumulative time data Tc can be determined as the value obtained by adding the cumulative time change ΔTc to the immediately preceding cumulative time data Tc (Tc = Tc + ΔTc).

[0115] Referring to detail g, the voltage deviation change △Vdev_c can be represented by subtracting the voltage deviation Vdev_d of the immediately preceding operating state from the voltage deviation Vdev_c of the charging state (△Vdev_c = Vdev_c - Vdev_d). The SOC deviation change △SOCdev_c can be represented by subtracting the SOC deviation SOCdev_d of the immediately preceding operating state from the SOC deviation SOCdev_c of the charging state (△SOCdev_c = SOCdev_c - SOCdev_d). The cumulative time change △Tc can be represented by subtracting the cumulative time Td of the immediately preceding operating state from the cumulative time T_c of the charging state (△Tc = Tc - Td).

[0116] Next, when the battery management device changes from the operating state to the terminated state (d), the control unit 100 can store the voltage deviation accumulation data acc_Vdev_d, the SOC deviation accumulation data acc_SOCdev_d, and the accumulation time data Td as storage value e in the memory 120. In the terminated state, the voltage deviation Vdev_end, SOC deviation SOCdev_end, measurement time Tend, maximum voltage deviation Vdev_max, and maximum SOC deviation SOCdev_max can be stored together with the accumulation data. Therefore, as described above, the control unit 100 can use the non-accumulated deviation data and the accumulated deviation data to determine whether the battery cell is abnormal.

[0117] Referring to the storage value details f, the cumulative voltage deviation data acc_Vdev_d can be determined as the value obtained by adding the voltage deviation change ΔVdev_d to the immediately preceding cumulative voltage deviation data acc_Vdev_d (acc_Vdev_d = acc_Vdev_d + ΔVdev_d). The cumulative SOC deviation data acc_SOCdev_d can be determined as the value obtained by adding the SOC deviation change ΔSOCdev_d to the immediately preceding cumulative SOC deviation data acc_SOCdev_d (acc_SOCdev_d = acc_SOCdev_d + ΔSOCdev_d). The cumulative time data Td can be determined as the value obtained by adding the cumulative time change ΔTd to the immediately preceding cumulative time data Td (Td = Td + ΔTd).

[0118] Referring to detail g, the voltage deviation change △Vdev_d can be represented by subtracting the voltage deviation Vdev_c of the immediately preceding charging state from the voltage deviation Vdev_end in the final state (△Vdev_d = Vdev_end - Vdev_c). The SOC deviation change △SOCdev_d can be represented by subtracting the SOC deviation SOCdev_c of the immediately preceding charging state from the SOC deviation SOCdev_end in the final state (△SOCdev_d = SOCdev_end - SOCdev_c). The cumulative time change △Td can be represented by subtracting the cumulative time Tc of the immediately preceding initial state from the cumulative time Tend in the operating state (△Td = Tend - Tc).

[0119] The stored values ​​described above are examples and can be modified in various ways depending on charge-discharge cycles. The process of determining the cause of a defect based on the stored values, performed by the battery management device according to an embodiment, will be described below.

[0120] Figures 7 to 10 This is a graph showing the accumulated deviation data obtained in the battery management device according to the embodiment.

[0121] Reference Figure 7 The control unit 100 can generate and visualize cumulative data based on battery usage patterns, and interpret the visualizations to determine the causes of deviations. Figure 7 In the above, (a) can represent the total voltage deviation V_dev, (b) can represent the accumulated voltage deviation data acc_Vdev_c in charging mode, (c) can represent the accumulated voltage deviation data acc_Vdev_d in operating mode, and (d) can represent the accumulated voltage deviation data cc_Vdev_end in end mode or idle mode.

[0122] from Figure 7 It can be seen that the voltage deviation of the battery cell increases overall based on the increase of the total voltage deviation (a). Furthermore, the battery management device according to the embodiment can obtain cumulative deviation data based on the battery usage pattern, thereby determining the cause of the deviation and the corresponding cause of the defect.

[0123] Furthermore, since the voltage deviation accumulation data (b) in charging mode accumulates with a positive deviation, while the voltage deviation accumulation data (c) in operating mode accumulates with a negative deviation, the control unit 100 can determine the corresponding cause of the deviation. Since the voltage deviation accumulation data (d) in end mode or idle mode accumulates with a positive deviation, the corresponding cause of the deviation can also be determined.

[0124] Refer to together Figure 8 ,exist Figure 8 In the above, (a) can represent the total voltage deviation V_dev, (b) can represent the accumulated voltage deviation data acc_Vdev_on in the charge / discharge mode, and (c) can represent the accumulated voltage deviation data acc_Vdev_end in the idle mode.

[0125] exist Figure 7 In the charging mode, the accumulated voltage deviation data and the accumulated voltage deviation data in the operating mode can have positive and negative deviations, respectively. Figure 8 In the process, since positive and negative voltage deviations are canceled out, the cumulative voltage deviation data (b) under the charge and discharge modes, including the charging mode and the operating mode, can be indicated as a positive deviation with a small slope.

[0126] Therefore, the control unit 100 can determine that the percentage increase in total voltage deviation (a) caused by the accumulated voltage deviation data (c) in the idle mode is greater than the percentage increase in total voltage deviation (a) caused by the accumulated voltage deviation data (b) in the charge / discharge mode. Subsequently, the control unit 100 can determine the cause of the deviation and the corresponding defect by determining the percentage increase in total voltage deviation (a).

[0127] For example, when assuming the voltage deviation increases at a rate of 32 mV / day, the control unit 100 can determine that this rate is similar to the deviation increase rate under low voltage conditions, thereby identifying the cause of the deviation as low voltage, selecting the corresponding defect cause, and sending it to the external device 4.

[0128] Similarly, refer to Figure 9 and Figure 10 The control unit 100 can generate and visualize cumulative data based on battery usage patterns, and interpret the visualizations to determine the causes of deviations. Figure 9 In the above, (a) can represent the total SOC deviation SOC_dev, (b) can represent the accumulated SOC deviation data acc_SOCdev_c in charging mode, (c) can represent the accumulated SOC deviation data acc_SOCdev_d in operating mode, and (d) can represent the accumulated SOC deviation data cc_SOCdev_end in end mode or idle mode.

[0129] from Figure 9 It can be seen that the SOC deviation of the battery cell increases overall based on the increase of the total SOC deviation (a). Furthermore, the battery management device according to the embodiment can obtain cumulative deviation data based on the battery usage pattern, thereby determining the cause of the deviation and the corresponding cause of the defect.

[0130] Furthermore, since the SOC deviation accumulation data (b) in charging mode accumulates with a negative deviation, while the SOC deviation accumulation data (c) in operating mode accumulates with a positive deviation, the control unit 100 can determine the corresponding cause of the deviation. Since the SOC deviation accumulation data (d) in end mode or idle mode accumulates with a positive deviation, the corresponding cause of the deviation can be determined.

[0131] Refer to together Figure 10 ,exist Figure 10 In the table, (a) can represent the total SOC deviation SOC_dev, (b) can represent the cumulative SOC deviation data acc_SOCdev_on in charge / discharge mode, and (c) can represent the cumulative SOC deviation data acc_SOCdev_end in idle mode.

[0132] exist Figure 9 In the charging mode, the accumulated SOC deviation data and the accumulated SOC deviation data in the operating mode can have negative and positive deviations, respectively. Figure 10 In the figure, since positive and negative voltage deviations are canceled out, the cumulative SOC deviation data (b) under the charge and discharge modes, including the charging mode and the operating mode, can be indicated as a near-horizontal graph.

[0133] Therefore, the control unit 100 can determine that the cause of the increase in total SOC deviation (a) originates from the idle mode. For example, assuming that the SOC deviation increases at a rate of 4.3% / day, the control unit 100 can determine that this rate is similar to the deviation increase rate under low voltage conditions, thereby identifying the cause of the deviation as low voltage, selecting the corresponding defect cause, and sending it to the external device 4.

[0134] Therefore, in addition to voltage deviation and SOC deviation, the battery management device according to the embodiment can also use cumulative deviation data to analyze the causes of battery defects in more detail.

[0135] Figure 11 This is a flowchart of a battery management method according to an implementation method. Figure 12 It is shown continuously Figure 11 The flowchart of the battery management method.

[0136] Reference Figure 11 In operation 1100, the control unit 100 can receive the current and voltage of multiple battery cells from the sensor unit 14. Subsequently, in operation 1110, the control unit 100 can generate voltage deviation accumulation data by accumulating the deviations between the voltages of the multiple battery cells.

[0137] In operation 1120, control unit 100 can determine the state of charge (SOC) of multiple battery cells based on the current of multiple battery cells. Subsequently, in operation 1130, control unit 100 can generate SOC deviation accumulation data by accumulating the deviations between the SOCs of the multiple battery cells.

[0138] In this scenario, during operation 1140, the control unit 100 can determine the cause of defects in multiple battery cells based on accumulated voltage deviation data and accumulated SOC deviation data. Specifically, the control unit 100 can determine the cause of defects in battery cells based on information obtainable from each of the accumulated voltage deviation data and accumulated SOC deviation data, or based on information obtainable by analyzing the accumulated voltage deviation data and accumulated SOC deviation data together.

[0139] Continue to refer to Figure 12 In operation 1200, the control unit 100 can determine whether the accumulated voltage deviation data and the accumulated SOC deviation data have entered the normal range. That is, when the deviation indicated in the accumulated voltage deviation data and the accumulated SOC deviation data decreases to within the reference range, the control unit 100 can determine that the accumulated voltage deviation data and the accumulated SOC deviation data have entered the normal range. The control unit 100 can determine whether the deviation accumulation data has entered the normal range, and thereby use this determination to identify the cause of the deviation.

[0140] For example, when the voltage deviation accumulation data and SOC deviation accumulation data show deviations within the range that are identified as battery defects during a random first time period, and then enter the normal range after the first time period, the control unit 100 can use the first time period as a factor in the deviation cause analysis.

[0141] In this scenario, when the accumulated voltage deviation data and accumulated SOC deviation data enter the normal range, the control unit 100 can increment the deviation count COUNTdev. When the accumulated voltage deviation data and accumulated SOC deviation data enter the normal range, the control unit 100 can... Figure 6 The stored value e corresponds to the accumulated voltage deviation data, accumulated SOC deviation data, accumulated time data, final voltage deviation, final SOC deviation, final elapsed time, maximum voltage deviation, and final SOC deviation initialization.

[0142] However, the control unit 100 can exclude deviation variations within the normal range from the deviation count based on the maximum deviations Vdev_max and SOCdev_max in the charge-discharge cycle according to the battery usage pattern.

[0143] When it is determined that the voltage deviation accumulation data and the SOC deviation accumulation data are within the normal range (yes in operation 1200), the control unit 100 can temporarily store the maximum deviation of the current charge-discharge cycle in operation 1210.

[0144] Subsequently, in operation 1220, the control unit 100 can compare the maximum deviation previously stored in a previous charge-discharge cycle with the maximum deviation in the current cycle. When the control unit 100 determines that the maximum deviation in the current cycle is greater than the maximum deviation previously stored in a previous charge-discharge cycle, in operation 1230, the control unit 100 can update the previously stored maximum deviation to the maximum deviation in the current cycle.

[0145] Therefore, the control unit 100 can continuously update the maximum deviation based on the maximum values ​​of the voltage deviation and SOC deviation that occur in the battery cell, in order to determine the cause of the battery cell defect.

[0146] Furthermore, the control unit 100 can grant the user permission to initialize the deviation count COUNT_dev data and the maximum deviations Vdex_max and SOCdev_max data only when the user resolves the cause of the battery cell defect. Therefore, the reliability of the deviation count COUNT_dev data and the maximum deviations Vdex_max and SOCdev_max data can be improved.

[0147] Therefore, in addition to voltage deviation and SOC deviation data, the battery management device according to the embodiment can also use voltage deviation accumulation data and SOC deviation accumulation data to diagnose the causes of battery defects in more detail.

[0148] Furthermore, the disclosed embodiments can be implemented in the form of a recording medium storing computer-executable instructions. The instructions can be stored as program code, and when executed by a processor, a program module can be generated and operations according to the disclosed embodiments can be performed. The recording medium can be implemented as a computer-readable recording medium.

[0149] Computer-readable recording media can include any type of recording medium that stores instructions that can be interpreted by a computer. For example, computer-readable recording media can include read-only memory (ROM), random access memory (RAM), magnetic tape, magnetic disk, flash memory, optical data storage devices, etc.

[0150] Furthermore, computer-readable recording media may be provided in the form of non-transitory storage media. Here, the term "non-transitory storage media" simply means a storage medium that is a tangible device and does not include signals (e.g., electromagnetic waves), but this term does not distinguish between cases where data is stored semi-permanently in a storage medium and cases where data is temporarily stored in a storage medium. For example, "non-transitory storage media" may include buffers for temporarily storing data.

[0151] According to embodiments of this disclosure, methods according to various embodiments of this disclosure can be included and provided in a computer program product. The computer program product can be traded as a product between a seller and a buyer. The computer program product can be distributed in the form of a machine-readable recording medium (e.g., an optical disc read-only memory (CD-ROM)) or via an app store (e.g., the Play Store). TM Online distribution (e.g., download or upload) or direct distribution between two user devices (e.g., smartphones). When distributed online, at least a portion of the computer program product (e.g., a downloadable application) may be temporarily generated or at least temporarily stored in a machine-readable recording medium, such as the memory of a manufacturer's server, an app store's server, or the memory of a relay server 102.

[0152] Although all components constituting the embodiments disclosed herein have been described above as operating in combination or in combination, the embodiments disclosed herein are not necessarily limited to this embodiment. That is, within the scope of the embodiments disclosed herein, all components can be operated by selectively combining them into one or more.

[0153] Furthermore, terms such as "comprising," "constituting," or "having" described above may mean that the corresponding component is inherent unless otherwise stated, and should therefore be interpreted as further including rather than excluding other components. Unless otherwise defined, all terms, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments disclosed herein pertain. Unless expressly defined in this document, commonly used terms, like those defined in dictionaries, should be interpreted as having the same meaning as in the context of the relevant art and should not be interpreted as having an ideal or overly formal meaning.

[0154] The above description is merely an illustration of the technical ideas disclosed herein, and various modifications and variations will be possible for those skilled in the art without departing from the basic characteristics of the embodiments disclosed herein. Therefore, the embodiments disclosed herein are intended to describe, not limit, the technical spirit of the embodiments disclosed herein, and the scope of the technical spirit disclosed herein is not limited by these embodiments. The scope of protection of the technical spirit disclosed herein should be interpreted by the appended claims, and all technical spirit within the same scope should be understood to be included within the scope of this document.

Claims

1. A battery management device, the battery management device comprising: A sensor unit configured to measure the voltage and current of a plurality of battery cells; as well as Control unit, the control unit being configured to: Generate voltage deviation accumulation data by accumulating the voltage deviations between the plurality of battery cells; The state of charge (SOC) of the plurality of battery cells is determined based on the current, and accumulated SOC deviation data is generated by accumulating the deviations between the SOCs of the plurality of battery cells; and The causes of defects in the plurality of battery cells are determined based on the accumulated voltage deviation data and the accumulated SOC deviation data.

2. The battery management device according to claim 1, wherein, The control unit is also configured to determine the time required for the voltage deviation and SOC deviation to increase based on the accumulated voltage deviation data and the accumulated SOC deviation data, and to determine the cause of the deviation corresponding to the time required for the increase as the cause of the defect in the plurality of battery cells.

3. The battery management device according to claim 1, wherein, The control unit is further configured to determine a deviation count of voltage deviation and SOC deviation based on the accumulated voltage deviation data and the accumulated SOC deviation data, and to determine the deviation cause corresponding to the deviation count as the defect cause of the plurality of battery cells.

4. The battery management device according to claim 1, wherein, The control unit is further configured to determine the maximum deviation of the voltage deviation and the SOC deviation based on the accumulated voltage deviation data and the accumulated SOC deviation data, and to determine the deviation cause corresponding to the maximum deviation as the defect cause of the plurality of battery cells.

5. The battery management device according to claim 1, wherein, The control unit is also configured to determine the required time from the time of maximum deviation occurrence to the time of the next maximum deviation occurrence based on the voltage deviation accumulation data and the SOC deviation accumulation data, and to determine the deviation cause corresponding to the required time as the defect cause of the plurality of battery cells.

6. The battery management device according to claim 6, wherein, The control unit is also configured to determine the maximum deviation occurrence rate based on the required time, and to determine the deviation cause corresponding to the maximum deviation occurrence rate as the defect cause of the plurality of battery cells.

7. The battery management device according to claim 1, wherein, The control unit is also configured to reset the accumulated data based on the voltage deviation accumulated data and the SOC deviation accumulated data being within the normal range.

8. The battery management device according to claim 7, wherein, The control unit is also configured to store the maximum deviation up to the reset time based on the reset of the accumulated data, wherein the previously stored maximum deviation is compared with the maximum deviation up to the reset time, and the larger value between the previously stored maximum deviation and the maximum deviation up to the reset time is stored.

9. A battery management method, the battery management method comprising the following steps: Measure the voltage and current of multiple battery cells; Generate voltage deviation accumulation data by accumulating the voltage deviations between the plurality of battery cells; The state of charge (SOC) of the plurality of battery cells is determined based on the current. Generate SOC deviation accumulation data obtained by accumulating the SOC deviations among the multiple battery cells; as well as The causes of defects in the plurality of battery cells are determined based on the accumulated voltage deviation data and the accumulated SOC deviation data.

10. The battery management method according to claim 9, wherein, The steps for determining the cause of the defects in the plurality of battery cells include the following steps: determining the time required for the increase of voltage deviation and SOC deviation based on the accumulated voltage deviation data and the accumulated SOC deviation data; and determining the deviation cause corresponding to the time required for the increase as the cause of the defects in the plurality of battery cells.

11. The battery management method according to claim 9, wherein, The steps for determining the cause of the defects in the plurality of battery cells include the following steps: determining a deviation count of voltage deviation and SOC deviation based on the accumulated voltage deviation data and the accumulated SOC deviation data; and determining the deviation cause corresponding to the deviation count as the cause of the defects in the plurality of battery cells.

12. The battery management method according to claim 9, wherein, The steps for determining the cause of the defects in the plurality of battery cells include the following steps: determining the maximum deviation of voltage deviation and SOC deviation based on the voltage deviation cumulative data and the SOC deviation cumulative data; and determining the deviation cause corresponding to the maximum deviation as the cause of the defects in the plurality of battery cells.

13. The battery management method according to claim 9, wherein, The steps for determining the cause of the defects in the plurality of battery cells include the following steps: determining the required time from the time of the maximum deviation occurrence to the time of the next maximum deviation occurrence based on the voltage deviation accumulation data and the SOC deviation accumulation data; and determining the deviation cause corresponding to the required time as the cause of the defects in the plurality of battery cells.

14. The battery management method according to claim 9, wherein, The step of determining the cause of the defect in the plurality of battery cells includes the following steps: determining the maximum deviation occurrence rate based on the required time; and determining the deviation cause corresponding to the maximum deviation occurrence rate as the cause of the defect in the plurality of battery cells.

15. The battery management method according to claim 9, further comprising the following steps: The accumulated data is reset based on the fact that the accumulated voltage deviation data and the accumulated SOC deviation data are within the normal range.

16. The battery management method according to claim 15, further comprising the following steps: The maximum deviation up to the reset time is stored based on the reset of the accumulated data, wherein the previously stored maximum deviation is compared with the maximum deviation up to the reset time, and the larger value between the previously stored maximum deviation and the maximum deviation up to the reset time is stored.

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