Battery management device and battery management method

Abstract

A battery management method of the present disclosure comprises the steps of: obtaining a noise level on the basis of a cell voltage change amount of a selected battery cell selected from a slave including a plurality of battery cells; obtaining a deviation of the selected battery cell on the basis of a cell voltage average value change amount, which is a difference between cell voltage average values of the selected battery cell for each of a current section and a previous section, a change amount average value, which is an average value of the cell voltage average value change amounts of the plurality of battery cells, and the noise level; obtaining a final signal of the selected battery cell on the basis of the deviation; and determining whether the selected battery cell is abnormal on the basis of a first comparison result of a level of the final signal and a first threshold value.

Description

Battery management device and battery management method

[0001] This application claims the benefit of priority to Republic of Korea Patent Application No. 10-2024-0118399, dated September 2, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a battery management device and a battery management method.

[0003] Batteries are widely used as an energy source in various electronic devices. To ensure safety, technologies for assessing and diagnosing battery status are becoming increasingly important. For example, battery voltage can be used to diagnose batteries. However, if there is noise in the voltage, it can be difficult to determine whether a subtle inflection signal is due to noise, potentially increasing the risk of false positives.

[0004] The present disclosure provides a battery management device and a battery management method that improve the safety of a battery.

[0005] The technical tasks to be achieved by this embodiment are not limited to the technical tasks described above, and other technical tasks can be inferred from the following embodiments.

[0006] A battery management method according to an embodiment of the present disclosure may include a step of obtaining a noise level based on a cell voltage variation amount of a selected battery cell selected from a slave including a plurality of battery cells, a step of obtaining a cell voltage average variation amount which is a difference between cell voltage average values ​​of the selected battery cell for each of a current section and a previous section, a variation average value which is an average of cell voltage average variation amounts of the plurality of battery cells, and a step of obtaining a deviation of the selected battery cell based on the noise level, a step of obtaining a final signal of the selected battery cell based on the variation amount, and a step of determining whether the selected battery cell is abnormal based on a first comparison result of the level of the final signal and a first threshold value.

[0007] In an embodiment, the step of obtaining the final signal may include the step of obtaining the slope of the deviation, which is the difference between the deviation change amount of the deviation and the deviation average change amount, and the step of obtaining the final signal corresponding to the deviation and the slope.

[0008] In an embodiment, the step of obtaining the final signal further includes a step of obtaining a value obtained by dividing the deviation by a noise reduction level as a noise reduction value, and the step of obtaining the final signal corresponding to the deviation and the slope may obtain a value obtained by multiplying the deviation, the slope, and the noise reduction value as the final signal.

[0009] In an embodiment, the deviation change amount may be a value obtained by multiplying the difference in deviation of the selected battery cell between the current section and the previous section by a slope scale.

[0010] In an embodiment, the average deviation value change amount may be a value obtained by multiplying the difference between the average values ​​of the deviations of the plurality of battery cells for the current section and the previous section by a slope scale.

[0011] In an embodiment, the step of determining whether the selected battery cell is abnormal may include the step of obtaining a second comparison result by comparing a deviation ratio based on the first maximum and minimum values ​​of the deviation with a second threshold value, and the step of determining whether the selected battery cell is abnormal based on the first comparison result and the second comparison result.

[0012] In an embodiment, the step of obtaining the second comparison result may include the step of obtaining a second maximum value of the deviation excluding the first maximum value and a first ratio of the first maximum value, the step of obtaining a second ratio of one of the first maximum value and the second maximum value and the minimum value, and the step of obtaining a difference between the first ratio and the second ratio as the deviation ratio.

[0013] In an embodiment, the step of obtaining the noise level may include the step of obtaining a first operation value obtained by dividing the sum of squares of the cell voltage variations by the number of cell voltage variations, the step of obtaining a second operation value which is the square of the value obtained by dividing the sum of the cell voltage variations by the number of cell voltage variations, and the step of obtaining a third operation value obtained by multiplying a noise scale by a root value of a difference between the first operation value and the second operation value as the noise level.

[0014] In an embodiment, the step of obtaining the deviation may include the step of obtaining a difference between the amount of change in the average cell voltage of the selected battery cell for the current section and the average value of the amount of change of the plurality of battery cells for the previous section as a first calculation value, the step of obtaining a difference between the amount of change in the average cell voltage of the selected battery cell for the current section and the average value of the amount of change of the plurality of battery cells for the current section as a second calculation value, the step of obtaining a value obtained by dividing the sum of the first difference value and the second difference value by the average value of the amount of change of the plurality of battery cells for the current section as a third calculation value, and the step of obtaining a fourth calculation value obtained by dividing the third calculation value by the noise level as the deviation.

[0015] A battery management device according to an embodiment of the present disclosure may include an information acquisition interface for acquiring cell voltages of each of a plurality of battery cells included in a slave, and a processor for acquiring a noise level based on a cell voltage variation amount of a selected battery cell selected from the slave, acquiring a cell voltage average variation amount which is a difference between cell voltage average values ​​of the selected battery cell for each of a current section and a previous section, an average variation amount which is an average of cell voltage average variation amounts of the plurality of battery cells, and a deviation of the selected battery cell based on the noise level, acquiring a final signal of the selected battery cell based on the variation, and determining whether the selected battery cell is abnormal based on a first comparison result of the level of the final signal and a first threshold value.

[0016] A computer-readable recording medium according to an embodiment of the present disclosure may include a program for executing a battery management method on a computer.

[0017] Specific details of other embodiments are included in the detailed description and drawings.

[0018] According to the proposed embodiment, one or more of the following effects can be expected.

[0019] According to an embodiment of the present disclosure, a battery management device and a battery management method that improve the safety of a battery can be provided.

[0020] According to an embodiment, a battery management device and method for accurately diagnosing the condition of a battery can be provided. According to an embodiment, the accuracy of the diagnosis can be improved. According to an embodiment, the rate of overdiagnosis due to noise can be reduced.

[0021] The effects of the invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0022] Figure 1 is a drawing for explaining a battery management device according to an embodiment.

[0023] Figure 2 is a block diagram for explaining a battery management device according to an embodiment.

[0024] Figure 3 is a flowchart for explaining a battery management method according to an embodiment.

[0025] Figure 4 is a drawing for explaining the noise level according to an embodiment.

[0026] FIG. 5 is a drawing for explaining the cell voltage average value, the amount of change in the cell voltage average value, and the amount of change average value according to an embodiment.

[0027] Figure 6 is a drawing for explaining the deviation, slope, noise reduction value, and final signal according to an embodiment.

[0028] Figure 7 is a drawing for explaining a method for obtaining a noise reduction value according to an embodiment.

[0029] Figure 8 is a drawing for explaining a battery management method according to an embodiment.

[0030] The terms used in the embodiments have been selected from widely used and common terms, taking into account the functions of the present disclosure. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, in which case their meanings will be described in detail in the relevant description. Therefore, the terms used in this disclosure should not be defined simply as names of terms, but rather based on the meanings of the terms and the overall content of the present disclosure.

[0031] When a part of the specification is said to "include" a component, this does not exclude other components, but rather implies the inclusion of other components, unless otherwise specifically stated. Furthermore, terms such as "part" and "module" used in the specification refer to a unit that processes at least one function or operation, which may be implemented in hardware, software, or a combination of hardware and software.

[0032] Below, embodiments of the present disclosure are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present disclosure. However, the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein.

[0033] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0034] Figure 1 is a drawing for explaining a battery management device according to an embodiment.

[0035] Referring to FIG. 1, a battery management device (100) according to an embodiment of the present disclosure can manage at least one battery. The battery can supply electrical energy to various types of electronic devices. For example, the electronic devices can be vehicles, drones, data centers, communication base stations, commercial facilities, industrial facilities, mobile devices, etc. The battery can refer to battery cells (211, 221).

[0036] Battery cells (211, 221) can store or release energy through electrochemical reactions. The battery cells (211, 221) may be secondary batteries capable of repeated charging and discharging. The battery cells (211, 221) may include a positive electrode, a negative electrode, an electrolyte, and an outer case. For example, the positive electrode may include at least one of materials such as lithium cobalt oxide, lithium iron phosphate, and nickel manganese cobalt oxide. The negative electrode may include at least one of materials such as graphite and silicon. The electrolyte may include at least one of an organic solvent and a lithium salt mixture as a medium through which lithium ions move. The outer case may protect other components of the battery cells (211, 221) from the external environment. For example, the outer case may be an aluminum-polymer composite film having a flexible shape, or a case having a square or cylindrical shape. In an embodiment, the battery cell (211, 221) may further include a separator that prevents contact between the positive and negative electrodes. In an embodiment, the battery cell (211, 221) may be various types of secondary batteries, such as a lithium ion battery, a lithium ion polymer battery, a nickel-cadmium battery, a nickel-metal hydride battery, and an all-solid-state battery. A plurality of battery cells (211, 221) may be packaged into a single unit, such as a battery module or a battery pack. Meanwhile, the battery cell (211, 221) may be simply referred to as a cell.

[0037] A battery management device (100) according to an embodiment of the present disclosure can manage at least one slave (210, 220). For example, the battery management device (100) may be a battery management system mounted on a vehicle. As another example, the battery management device (100) may be a server. However, this is merely an example, and the battery management device (100) may be implemented as various types of electronic devices.

[0038] A slave (210, 220) may include a plurality of battery cells (211, 221). The plurality of battery cells (211, 221) within the same slave (210, 220) may be connected in series, parallel, or a combination thereof. The number of battery cells (211) included in one slave (210) may be the same as or different from the number of battery cells (221) included in another slave (220). In an embodiment, the slave (210, 220) may be a group of units in which battery cells (211, 221) are monitored or controlled. In an embodiment, a battery module may include at least one slave (210, 220). Hereinafter, a description will be given based on one slave (210). The description for one slave (210) may be equally applicable to another slave (220).

[0039] In an embodiment, the battery management device (100) can diagnose whether each of the plurality of battery cells (211) included in the slave (210) has an abnormality using the cell voltage of each of the plurality of battery cells (211). According to the present disclosure, even when noise exists in the cell voltage, the accuracy of the diagnosis can be improved and the over-inspection rate of the diagnosis can be reduced. Details related to this will be described in detail with reference to the attached drawings.

[0040]

[0041] Figure 2 is a block diagram for explaining a battery management device according to an embodiment.

[0042] Referring to FIG. 2, a battery management device (100) according to an embodiment may include an information acquisition interface (110) and a processor (120).

[0043] The information acquisition interface (110) can acquire the cell voltage of the battery cell (211). In an embodiment, the information acquisition interface (110) can periodically acquire the cell voltage of the battery cell (211) over time. The information acquisition interface (110) can transmit the cell voltage of the battery cell (211) to the processor (120).

[0044] In one embodiment, the information acquisition interface (110) may include a voltage sensor that acquires the cell voltage by measuring the potential difference between the positive and negative electrodes of the battery cell (211). In this case, the information acquisition interface (110) may acquire the cell voltage by directly measuring the cell voltage of the battery cell (211).

[0045] In another embodiment, the information acquisition interface (110) may include a communication circuit that performs communication via a wired communication channel or a wireless communication channel. The communication circuit may receive the cell voltage of the battery cell (211) from an external device. For example, the communication circuit may transmit and receive data with the external device. In an embodiment, the communication circuit may perform communication via a communication standard including at least one of various methods such as CAN (Controller Area Network), UART (Universal Asynchronous Receiver-Transmitter), I2C (Inter-Integrated Circuit), SPI (Serial Peripheral Interface), SMBus (System Management Bus), Ethernet, BLE (Bluetooth Low Energy), Bluetooth, Zigbee, Wi-Fi, and LIN (Local Interconnect Network). The external device may include at least one of various types of devices such as a battery cell (211), a battery module, a battery pack, a vehicle control system, a charger, and a server.

[0046] The processor (120) can control the overall operation of the battery management device (100). The processor (120) can process or calculate data. For example, the processor (120) can include at least one of various types of processors, such as a central processing unit, a digital signal processor, a microcontroller, and an application processor. The processor (120) can receive the cell voltage of each battery cell (211) from the information acquisition interface (110).

[0047] In an embodiment, the battery management device (100) may further include memory. The memory may store various information. For example, the memory may include at least one of various types of storage devices, such as Random Access Memory (RAM), a hard disk drive, a Solid State Drive (SSD), a portable flash memory, and a memory card. In an embodiment, the memory may store data used in the operation of the processor (120) or result data of the operation. In an embodiment, the memory may store a program executed by the processor (120). In an embodiment, the memory may store information about each battery cell (211) included in the slave (210).

[0048] The processor (120) can obtain a noise level based on the cell voltage variation of the selected battery cell selected from the slave (210). In an embodiment, the processor (120) can obtain a noise level based on a plurality of cell voltage variations of the selected battery cell.

[0049] Here, the selected battery cell is one of the plurality of battery cells (211) included in the slave (210), and may be a battery cell to be determined whether there is an abnormality. For example, the processor (120) may select a first battery cell among the plurality of battery cells (211) included in the slave (210) and determine whether there is an abnormality in the first battery cell. In addition, the processor (120) may select a second battery cell among the plurality of battery cells (211) included in the slave (210) and determine whether there is an abnormality in the second battery cell. The processor (120) may select each of the plurality of battery cells (211) included in the slave (210) and determine whether there is an abnormality in each of the selected battery cells. This may be performed simultaneously or sequentially.

[0050] The cell voltage change amount can represent the degree to which the cell voltage changes during one offset time. The offset time can be a preset time interval. For example, the time interval length of the offset time can be set to 1 second. However, this is only one embodiment, and the time interval length of the offset time can be modified and set to one of various values ​​such as 0.5 seconds, 2 seconds, or 5 seconds. The noise level can represent the degree of noise present in the cell voltage. For example, the higher the noise level, the greater the noise ratio, and the lower the noise level, the smaller the noise ratio.

[0051] In an embodiment, the cell voltage change amount may be the absolute value of the difference in cell voltages for each of the start and end times of the offset time. For example, when the offset time is set to 1 second, the start time of the first offset time may be 1 second, the end time of the first offset time may be 2 seconds, the start time of the second offset time may be 2 seconds, and the end time of the second offset time may be 3 seconds. In this case, the first cell voltage change amount for the first offset time may be the absolute value of the difference between the first cell voltage measured at 1 second and the second cell voltage measured at 2 seconds. The second cell voltage change amount for the second offset time may be the absolute value of the difference between the second cell voltage measured at 2 seconds and the third cell voltage measured at 3 seconds. In this manner, other cell voltage changes may be obtained.

[0052] In an embodiment, the processor (120) may obtain a noise level for each unit time based on the amount of change in cell voltage of the selected battery cell for each of at least one offset time included in each unit time. The unit time may have a preset time interval length. For example, when the current interval is the t-th unit time, the processor (120) may obtain a noise level for the t-th unit time based on the amount of change in cell voltage of the selected battery cell for each offset time included in the t-th unit time. In an embodiment, the time interval length of the offset time may be less than or equal to the time interval length of the unit time. Meanwhile, the unit time may be referred to as a unit time interval.

[0053] The processor (120) can obtain the deviation of the selected battery cell based on the variation in the average cell voltage of the selected battery cell, the variation average of the plurality of battery cells (211) included in the slave (210), and the noise level. In an embodiment, the processor (120) can obtain the deviation of the selected battery cell based on the variation in the average cell voltage of the selected battery cell for the current section, the variation average of the plurality of battery cells (211) included in the slave (210) for the current section and the previous section, respectively, and the noise level for the current section. For example, when the current section is the t-th unit time, the previous section may be the t-1-th unit time. Here, t may be a natural number greater than or equal to 2.

[0054] The change in the average cell voltage of the selected battery cell for the current section may be the difference between the average cell voltages of the selected battery cell for each of the current section and the previous section. For example, the change in the average cell voltage of the selected battery cell for the current section (e.g., the t-th unit time) may be the difference between the average cell voltage of the selected battery cell for the current section (e.g., the t-th unit time) and the average cell voltage of the selected battery cell for the previous section (e.g., the t-1-th unit time). The average cell voltage of the selected battery cell for the t-th unit time may be the average of the cell voltages of the selected battery cell during the t-th unit time.

[0055] In an embodiment, among multiple unit times, the current section (e.g., the t-th unit time) and the previous section (e.g., the t-1-th unit time) may each have the same time section length. For example, the time section length of the unit time may be set to 600 seconds. In this case, the first unit time may be set to 0 to 600 seconds, the second unit time may be set to 600 to 1200 seconds, the third unit time may be set to 1200 to 1800 seconds, etc. The first unit time may be the first unit time, the second unit time may be the second unit time, and the third unit time may be the third unit time. Meanwhile, 0 to 600 seconds of the first unit time may represent a time section greater than or equal to 0 seconds and less than 600 seconds. The same method may be applied to other time sections. Meanwhile, the time interval length of the unit time can be set to one of various values ​​such as 100 seconds, 300 seconds, or 1000 seconds.

[0056] The average value of the amount of change of the plurality of battery cells (211) included in the slave (210) may be the average value of the amount of change of the average cell voltage of each of the plurality of battery cells (211) included in the slave (210). For example, the average value of the amount of change for the current section (e.g., the t-th unit time) may be the average value of the amount of change of the average cell voltage of each of the plurality of battery cells (211) for the current section (e.g., the t-th unit time). In addition, the average value of the amount of change for the previous section (e.g., the t-1-th unit time) may be the average value of the amount of change of the average cell voltage of each of the plurality of battery cells (211) for the previous section (e.g., the t-1-th unit time).

[0057] In an embodiment, the deviation of the selected battery cell for the current interval (e.g., the t-th unit time) may be inversely proportional to the noise level for the current interval (e.g., the t-th unit time). The higher the noise level, the smaller the deviation, and the lower the noise level, the larger the deviation.

[0058] The processor (120) may obtain the final signal of the selected battery cell based on the deviation of the selected battery cell. In an embodiment, the processor (120) may obtain the final signal of the selected battery cell for the current section based on the deviation of the selected battery cell for the current section. Here, the final signal may be an analog signal or a digital signal.

[0059] The processor (120) may determine whether the selected battery cell is abnormal based on the first comparison result of the level of the final signal and the first threshold value. For example, if the first comparison result indicates that the level of the final signal is lower than the first threshold value, the processor (120) may determine that the selected battery cell is normal. As another example, if the first comparison result indicates that the level of the final signal is higher than the first threshold value, the processor (120) may determine that the selected battery cell is abnormal (or abnormal).

[0060]

[0061] Figure 3 is a flowchart for explaining a battery management method according to an embodiment.

[0062] Referring to FIG. 3, a battery management method according to an embodiment may include a step (S310) of obtaining a noise level based on a cell voltage change amount of a selected battery cell selected from a slave (210), a step (S320) of obtaining a deviation of the selected battery cell based on a change amount of an average cell voltage of the selected battery cell for a current section, an average value of changes of a plurality of battery cells, and a noise level, a step (S330) of obtaining a final signal of the selected battery cell based on the deviation, and a step (S340) of determining whether the selected battery cell is abnormal based on a first comparison result of the level of the final signal and a first threshold value. Meanwhile, the battery management method of the present disclosure may be performed by a battery management device (100).

[0063] In an embodiment, the battery management method may obtain a noise level based on the cell voltage change amount of a selected battery cell selected from a slave (210) including a plurality of battery cells (211) (S310). In an embodiment, each cell voltage change amount may represent the degree to which the cell voltage has changed during each offset time. In an embodiment, the cell voltage may be obtained by the information acquisition interface (110). In an embodiment, the operation of obtaining the noise level may be performed by the processor (120).

[0064] In an embodiment, the step (S310) of obtaining the noise level of the selected battery cell may include the step of obtaining a first operation value obtained by dividing the sum of squares of cell voltage variations by the number of cell voltage variations, the step of obtaining a second operation value which is the square of the value obtained by dividing the sum of cell voltage variations by the number of cell voltage variations, and the step of obtaining a third operation value obtained by multiplying the root of the difference between the first operation value and the second operation value by a noise scale as the noise level. For example, the number of cell voltage variations may be equal to the number of offset times. The noise scale may be a preset constant.

[0065] In an embodiment, the battery management method may obtain a deviation of a selected battery cell based on a variation in the average cell voltage of the selected battery cell, an average variation of multiple battery cells, and a noise level (S320). In an embodiment, the operation of obtaining the deviation of the selected battery cell may be performed by the processor (120).

[0066] The amount of change in the average cell voltage of the selected battery cell for the current section (e.g., the t-th unit time) may be the difference between the average cell voltage of the selected battery cell for the current section (e.g., the t-th unit time) and the average cell voltage of the selected battery cell for the previous section (e.g., the t-1-th unit time). The average value of the amount of change of the plurality of battery cells included in the slave (210) may be the average value of the amount of change in the average cell voltage of each of the plurality of battery cells (211) included in the slave (210).

[0067] In an embodiment, the step (S320) of obtaining a deviation of a selected battery cell may include a step of obtaining a difference between a change in the average cell voltage of the selected battery cell for the current section (e.g., the t-th unit time) and an average value of changes of a plurality of battery cells for the previous section (e.g., the t-1th unit time) as a first calculation value, a step of obtaining a difference between a change in the average cell voltage of the selected battery cell for the current section (e.g., the t-th unit time) and an average value of changes of a plurality of battery cells for the current section (e.g., the t-1th unit time) as a second calculation value, a step of obtaining a value obtained by dividing the sum of the first difference value and the second difference value by the average value of changes of the plurality of battery cells for the current section (e.g., the t-th unit time) as a third calculation value, and a step of obtaining a fourth calculation value obtained by dividing the third calculation value by a noise level as a deviation.

[0068] In an embodiment, the battery management method may obtain a final signal of a selected battery cell based on the deviation of the selected battery cell (S330). In an embodiment, the operation of obtaining the final signal of the selected battery cell may be performed by the processor (120).

[0069] In an embodiment, the step of obtaining a final signal (S330) may include a step of obtaining a slope of the deviation, which is the difference between the deviation change amount of the deviation and the deviation average change amount, and a step of obtaining a final signal corresponding to the deviation and the slope.

[0070] In an embodiment, the step of obtaining the final signal (S330) may further include a step of obtaining a value obtained by dividing the deviation by the noise reduction level as a noise reduction value. In an embodiment, the step of obtaining the final signal corresponding to the deviation and the slope may obtain a value obtained by multiplying the deviation, the slope, and the noise reduction value as the final signal.

[0071] In an embodiment, the amount of change in deviation may be a value obtained by multiplying a slope scale by the difference in deviations of the selected battery cells for the current section (e.g., the t-th unit time) and the previous section (e.g., the t-1th unit time). In an embodiment, the amount of change in the average deviation may be a value obtained by multiplying a slope scale by the difference in average values ​​of deviations of multiple battery cells for the current section (e.g., the t-th unit time) and the previous section (e.g., the t-1th unit time).

[0072] In an embodiment, the battery management method may determine whether a selected battery cell is abnormal based on the level of the final signal and the first comparison result of the first threshold value (S340). In an embodiment, the operation of determining whether a selected battery cell is abnormal may be performed by the processor (120).

[0073] In an embodiment, the step (S340) of determining whether the selected battery cell is abnormal may include a step of obtaining a second comparison result by comparing a deviation ratio based on a first maximum and minimum value of the deviation with a second threshold value, and a step of determining whether the selected battery cell is abnormal based on the first comparison result and the second comparison result.

[0074] In an embodiment, the step of obtaining the second comparison result may include the step of obtaining a second maximum value of the deviation excluding the first maximum value and a first ratio of the first maximum value, the step of obtaining a second ratio of one of the first maximum value and the second maximum value and a minimum value, and the step of obtaining a difference between the first ratio and the second ratio as a deviation ratio.

[0075]

[0076] Figure 4 is a drawing for explaining the noise level according to an embodiment.

[0077] Referring to FIG. 4, in an embodiment, the battery management method can obtain the noise level for the t-th unit time by using the cell voltage change amount of the selected battery cell for each of the plurality of offset times included in the t-th unit time. In the following, it is assumed that the selected battery cell is the ith battery cell selected from the slave (210) including a plurality of battery cells (211). i is a natural number greater than or equal to 1. That is, the battery management method can obtain the noise level for the t-th unit time by using the plurality of cell voltage changes amount of the selected battery cell for each of the plurality of offset times. In an embodiment, the battery management method can obtain the noise level by using the standard deviation of the cell voltage change amount for each offset time.

[0078] In an embodiment, the cell voltage change amount of the selected battery cell can be obtained by the following mathematical expression 1 (10). The selected battery cell may be the i-th battery cell among a plurality of battery cells (211) included in the slave (210). i is a natural number greater than or equal to 1.

[0079] [Mathematical Formula 1]

[0080]

[0081] Here, v_dev[j] is the cell voltage change of the i-th battery cell for offset time j, and v i [j] is the cell voltage of the ith battery cell for offset time j, and v i [j-1] is the cell voltage of the ith battery cell for offset time j-1. j can represent the sequence or number of offset times included in the same unit time (e.g., the tth unit time, etc.). j is a natural number greater than or equal to 2.

[0082] In an embodiment, the battery management method may include a step of obtaining a first operation value obtained by dividing the sum of squares of cell voltage changes of selected battery cells by the number of cell voltage changes, a step of obtaining a second operation value which is the square of the sum of cell voltage changes divided by the number of cell voltage changes, and a step of obtaining a third operation value obtained by multiplying a noise scale by a root of a difference between the first operation value and the second operation value as a noise level.

[0083] For example, the noise level of the selected battery cell for the tth unit time can be obtained by the following mathematical expression 2 (20). The selected battery cell may be the ith battery cell among the plurality of battery cells (211) included in the slave (210). i is a natural number greater than or equal to 1.

[0084] [Mathematical Formula 2]

[0085]

[0086] Noise_Level i [t] is the noise level of the ith battery cell for the tth unit time. is the first operation value obtained by dividing the sum of the squares of the cell voltage changes by the number of cell voltage changes. is the sum of the squares of the cell voltage changes of the ith battery cell. m is a natural number greater than or equal to 2. m is the number of cell voltage changes, and m+1 is the number of cell voltages. v_dev[j] is the cell voltage change of the ith battery cell for offset time j. is the sum of the cell voltage changes. is the second operation value, which is the square of the sum of the cell voltage changes divided by the number of cell voltage changes. is the root of the difference between the first operation value and the second operation value. Noise_Scale is the noise scale and is a preset constant value. For example, the noise scale can be a value between 1 and 5. However, this is only an example, and the noise scale can be implemented by changing to various values.

[0087] According to an embodiment, the voltage measured for the battery cells included in each of the first and second slaves in different environments may appear as a first waveform (400). For example, if the first waveform (400) for voltage is converted into a voltage change amount using the first mathematical equation (10), it may appear as a second waveform (410). If the second waveform (410) for voltage change amount is converted into a noise level using the second mathematical equation (20), it may appear as a third waveform (420). For example, the upper part of the first waveform (400) shows a greater voltage inflection than the lower part, and in this case, like the upper part of the second waveform (410), the voltage change amount shows a greater inflection than the lower part, and may appear as a greater noise level in the third waveform (420). For example, a greater noise level may indicate a larger area in which inflection exists in voltage or voltage change amount.

[0088]

[0089] FIG. 5 is a drawing for explaining the cell voltage average value, the amount of change in the cell voltage average value, and the amount of change average value according to an embodiment.

[0090] Referring to FIG. 5, a battery management method according to an embodiment can measure the cell voltage of each of a plurality of battery cells (211) included in one slave (210). Here, the battery cells may be simply referred to as cells. For example, the plurality of cells may include a first cell to a third cell.

[0091] The battery management method can obtain the average cell voltage of each cell for each of multiple time units. For example, the time interval length of a unit time may be 600 seconds, but can be implemented with various values.

[0092] For example, as in the first table (510), the 1-1 cell voltage average value (Vavg11) may be the average value of the cell voltage of the first cell measured during the first unit time. The 1-2 cell voltage average value (Vavg12) may be the average value of the cell voltage of the first cell measured during the second unit time. The first unit time, the second unit time, the third unit time, etc. may be times in a continuous relationship with each other. For example, the end time of the first unit time may be the same as the start time of the second unit time, and the end time of the second unit time may be the same as the start time of the third unit time.

[0093] The battery management method can obtain the amount of change in the average cell voltage of each cell for each unit time. For example, the battery management method can obtain the amount of change in the average cell voltage of the first cell for the current section (e.g., the t-th unit time). The amount of change in the average cell voltage of the first cell for the current section (e.g., the t-th unit time) can be the absolute value of the difference between the average cell voltage of the first cell for each of the current section (e.g., the t-th unit time) and the previous section (e.g., the t-1-th unit time).

[0094] For example, if the current section is the second unit time, the change amount (dV1[2]) of the cell voltage average of the first cell for the current section (e.g., the second unit time) may be the absolute value of the difference between the 1-2 cell voltage average (Vavg12) of the first cell for the current section (e.g., the second unit time) and the 1-1 cell voltage average (Vavg11) of the first cell for the previous section (e.g., the first unit time). In the same manner, the change amount of the cell voltage average for each cell for each unit time may be obtained.

[0095] The battery management method can obtain an average value of change for each unit time. The average value of change for each unit time may be an average value of the average value of cell voltage changes of each of a plurality of cells included in one slave (210) for each unit time. For example, as shown in the second table (520), the average value of change for the second unit time (dV_avg[2]) may be an average value of the average value of cell voltage changes for each cell for the second unit time (dV1[2], dV2[2], dV3[2], ...). That is, the average value of change for the second unit time (dV_avg[2]) may be a value obtained by dividing the sum of the average value of change in cell voltage for each cell (dV1[2], dV2[2], dV3[2], ...) included in one slave (210) for the second unit time by the number (n) of cells included in one slave (210).

[0096]

[0097] Figure 6 is a drawing for explaining the deviation, slope, noise reduction value, and final signal according to an embodiment.

[0098] Referring to FIG. 6, the battery management method according to the embodiment can obtain the deviation of the selected battery cell based on the variation in the average cell voltage of the selected battery cell, the average variation of multiple battery cells, and the noise level. The same content described in FIG. 4 can be applied to the noise level. The same content described in FIG. 5 can be applied to the variation in the average cell voltage and the average variation.

[0099] In an embodiment, the battery management method may include a step of obtaining a difference between an average value of cell voltage of a selected battery cell for a current section (e.g., a t-th unit time) and an average value of changes of a plurality of battery cells for a previous section (e.g., a t-1th unit time) as a first calculation value, a step of obtaining a difference between an average value of cell voltage of a selected battery cell for a current section (e.g., a t-th unit time) and an average value of changes of a plurality of battery cells for the current section (e.g., a t-1th unit time) as a second calculation value, a step of obtaining a value obtained by dividing a sum of the first difference value and the second difference value by an average value of changes of a plurality of battery cells for the current section (e.g., a t-th unit time) as a third calculation value, and a step of obtaining a fourth calculation value obtained by dividing the third calculation value by a noise level as a deviation.

[0100] In an embodiment, the deviation of the selected battery cell for the current section can be obtained by mathematical expression 3 (30). For example, the selected battery cell may be the ith battery cell among a plurality of battery cells (211) included in the slave (210), the current section may be the tth unit time, and the previous section may be the t-1th unit time.

[0101] [Mathematical Formula 3]

[0102]

[0103] Here, dVsig i [t] is the deviation (or deviation signal) of the ith battery cell for the tth unit time. dV i [t] is the change in the average cell voltage of the i-th battery cell for the t-th unit time. dV_avg[t-1] is the average change in the plurality of battery cells (211) included in the slave (210) for the t-1-th unit time, and dV_avg[t] is the average change in the plurality of battery cells (211) included in the slave (210) for the t-th unit time. Noise_Level is the noise level of the i-th battery cell for the t-th unit time.

[0104] Here, (dV i[t]-dV_avg[t-1]) is the first operation value, and (dV i [t]-dV_avg[t]) is the second operation value, is the third operation value, is the fourth operation value.

[0105] In an embodiment, the battery management method may obtain a slope of the deviation, which is the difference between the deviation change amount and the deviation average change amount. In addition, the method may include a step of obtaining a final signal corresponding to the deviation and the slope.

[0106] In an embodiment, the slope of the deviation for the current section can be obtained by mathematical expression 4 (40). For example, the selected battery cell may be the ith battery cell among the plurality of battery cells (211) included in the slave (210), and the current section may be the tth unit time.

[0107] [Equation 4]

[0108]

[0109] Here, dVslope i [t] is the slope of the deviation of the ith battery cell for the tth unit time. ddVsig i [t] is the amount of change in the deviation of the i-th battery cell for the t-th unit time. ddVsig_avg[t] is the amount of change in the average deviation of multiple battery cells (211) included in the slave (210) for the t-th unit time.

[0110] In an embodiment, the battery management method may obtain a noise reduction value, which is a value obtained by dividing the deviation by the noise reduction level. In an embodiment, the noise reduction value may be obtained by mathematical expression 5 (50). For example, the selected battery cell may be the ith battery cell among a plurality of battery cells (211) included in the slave (210), and the current section may be the tth unit time.

[0111] [Equation 5]

[0112]

[0113] Here, NoiseReduction i [t] is the noise reduction value of the ith battery cell for the tth unit time. dVsig i [t] is the deviation of the ith battery cell for the tth unit time. Noise_Reduction_Level is the noise reduction level and can be a preset constant value.

[0114] In an embodiment, the final signal may correspond to the deviation and slope. For example, the battery management method may obtain the final signal as a product of the deviation and slope. In another example, the battery management method may obtain the final signal as a product of the deviation, slope, and noise reduction value.

[0115] In an embodiment, the final signal can be obtained by mathematical expression 6 (60).

[0116] [Equation 6]

[0117]

[0118] Here, dVfinal i [t] is the final signal of the ith battery cell for the tth unit time. That is, the final signal is acquired for each unit time and can be acquired for each battery cell. dVsig i [t] is the deviation of the ith battery cell for the tth unit time, and dVslope i [t] is the slope of the ith battery cell for the tth unit time, and NoiseReduction i [t] is the noise reduction value of the ith battery cell for the tth unit time.

[0119]

[0120] Figure 7 is a drawing for explaining a method for obtaining a noise reduction value according to an embodiment.

[0121] Referring to FIG. 7, the battery management method according to the embodiment can obtain the slope of the deviation, which is the difference between the amount of change in the deviation and the amount of change in the average value of the deviation.

[0122] In an embodiment, the deviation change amount of the deviation may be a value obtained by multiplying the difference in the deviation of the selected battery cell for the current section (e.g., the t-th unit time) and the previous section (e.g., the t-1th unit time) by the slope scale. For example, the deviation change amount may be obtained by mathematical expression 7 (70).

[0123] [Equation 7]

[0124]

[0125] ddVsig i [t] is the deviation change amount of the i-th battery cell for the t-th unit time. dVsig i [t] is the deviation of the ith battery cell for the tth unit time, and dVsig i [t-1] is the deviation of the ith battery cell for the t-1th unit time. Slope_Scale is the slope scale and can be a preset constant value.

[0126] In an embodiment, the average deviation value change amount may be a value obtained by multiplying the difference between the average values ​​of the deviations of multiple battery cells for the current section (e.g., the t-th unit time) and the previous section (e.g., the t-1th unit time) by a slope scale. For example, the average deviation value change amount may be obtained by mathematical expression 8 (80).

[0127] [Equation 8]

[0128]

[0129] ddVsig_avg[t] is the change in the average deviation value of the plurality of battery cells (211) included in the slave (210) for the t-th unit time. dVsig_avg[t] is the average value of the deviation of the plurality of battery cells (211) included in the slave (210) for the t-th unit time, and dVsig_avg[t-1] is the average value of the deviation of the plurality of battery cells (211) included in the slave (210) for the t-1-th unit time. Slope_Scale is a slope scale and may be a preset constant value.

[0130] In an embodiment, the average value of the deviation of the plurality of battery cells (211) included in the slave (210) for the t-th unit time can be obtained by mathematical expression 9 (90).

[0131] [Equation 9]

[0132]

[0133] Here, dVsig_avg[t] is the average value of the deviation of multiple battery cells (211) included in the slave (210) for the t-th unit time, and dVsig i [t] is the deviation of the ith battery cell for the tth unit time, and n is the number of multiple battery cells (211) included in the slave (210).

[0134] Figure 8 is a drawing for explaining a battery management method according to an embodiment.

[0135] Referring to FIG. 8, the battery management method according to the embodiment can periodically measure the cell voltage of each of the plurality of battery cells (211) included in the slave (210). For example, the cell voltage can be measured at every offset time.

[0136] The battery management method can select a time window (S803). The time window can have a preset time interval length. For example, the time window can have a time interval length of 7200 seconds. However, this is merely an example, and the time window can be implemented with various values. For example, the battery management method can select the T-th time window. Here, T can be a natural number greater than or equal to 1.

[0137] The battery management method can obtain the average cell voltage of each of the plurality of battery cells (211) for each of the plurality of unit times included in the selected time window based on the cell voltage of each of the plurality of battery cells (211) (S805). For example, the battery management method can obtain the average cell voltage of the selected battery cell for each of the t-th unit time and the t-1-th unit time. Here, t can be a natural number greater than or equal to 2. The unit time can have a preset time interval length. For example, the time interval length of the unit time can be 600 seconds. However, this is only one embodiment, and the time interval length of the unit time can be implemented by being modified to various values.

[0138] The battery management method can obtain the change in the average cell voltage of each battery cell for each of multiple unit times (S807). For example, the battery management method can obtain the change in the average cell voltage of a selected battery cell for the tth unit time.

[0139] The battery management method can obtain a noise level based on the cell voltage of each battery cell for each of a plurality of offset times included in each unit time (S810). Here, the unit time may be included in a selected time window. For example, the battery management method can obtain the noise level for the t-th unit time using the cell voltage change amount of the selected battery cell for each of a plurality of offset times included in the t-th unit time. The offset time may have a preset time interval length. For example, the time interval length of the offset time may be 1 second. However, this is only one embodiment, and the time interval length of the offset time may be implemented by being modified to various values.

[0140] The battery management method can obtain the deviation of each battery cell based on the variation in the average cell voltage of each battery cell included in the slave (210), the variation average of the plurality of battery cells (211) included in the slave (210), and the noise level of each battery cell (S820). For example, the battery management method can obtain the deviation of the selected battery cell based on the variation in the average cell voltage of the selected battery cell included in the slave (210), the variation average of the plurality of battery cells (211) included in the slave (210), and the noise level of the selected battery cell.

[0141] The battery management method can obtain the slope of the deviation of each battery cell based on the deviation of each battery cell (S821). In an embodiment, the battery management method can obtain the slope of the deviation of the selected battery cell, which is the difference between the deviation change amount of the selected battery cell and the deviation average change amount of the plurality of battery cells.

[0142] The battery management method can obtain a noise reduction value for each battery cell based on the deviation of each battery cell (S823). In an embodiment, the battery management method can obtain a noise reduction value for the selected battery cell by dividing the deviation of the selected battery cell by the noise reduction level.

[0143] The battery management method can obtain the final signal of each battery cell based on at least one of the deviation, slope, and noise reduction values ​​of each battery cell (S830). For example, the battery management method can obtain the product of the deviation, slope, and noise reduction values ​​of the selected battery cell as the final signal of the selected battery cell.

[0144] In an embodiment, the battery management method may determine whether each battery cell is abnormal based on the level of the final signal of each battery cell and the first comparison result of the first threshold value (S840). For example, if the level of the final signal of a selected battery cell is greater than the first threshold value, the selected battery cell may be determined to be abnormal.

[0145] In an embodiment, the battery management method may include a step (S825) of obtaining a deviation ratio of each battery cell based on the deviation of each battery cell. The deviation ratio may be obtained based on the first maximum and minimum values ​​of the deviation of the selected battery cell.

[0146] The battery management method may include a step of comparing a deviation ratio with a second threshold value to obtain a second comparison result. In an embodiment, the step of obtaining the second comparison result may include a step of obtaining a second maximum value of the deviation excluding the first maximum value and a first ratio of the first maximum value, a step of obtaining a second ratio of one of the first maximum value and the second maximum value and a minimum value, and a step of obtaining a difference between the first ratio and the second ratio as a deviation ratio.

[0147] The battery management method may include a step of determining whether a selected battery cell is abnormal based on a first comparison result and a second comparison result. For example, if the first comparison result indicates that the level of the final signal of the selected battery cell is greater than a first threshold value and the second comparison result indicates that the deviation ratio of the selected battery cell is greater than the second threshold value, the selected battery cell may be determined to be abnormal. For example, if the first comparison result indicates that the level of the final signal of the selected battery cell is less than the first threshold value and the second comparison result indicates that the deviation ratio of the selected battery cell is less than the second threshold value, the selected battery cell may be determined to be normal.

[0148] The electronic device according to the above-described embodiments may include a processor, a memory for storing and executing program data, a permanent storage such as a disk drive, a communication port for communicating with an external device, a user interface device such as a touch panel, a key, a button, etc.

[0149] The methods implemented by the software or algorithms disclosed in this document may be implemented as a program and stored on a computer-readable recording medium (or storage medium). The program may include computer-readable codes or program instructions for executing a plurality of steps. In one embodiment, the recording medium may be implemented as a device such as a server, a hard disk drive (HDD), a solid state drive (SSD), a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, or an optical data storage device. In one embodiment, when a camera of a machine such as a computer identifies a QR code or a document, the QR code or the document may also correspond to the recording medium, and the recording medium is not limited in type as long as it can be read and executed by a computer. In one embodiment, the program may be stored on a single recording medium, or may be distributed and stored on multiple recording media within a network-connected computer system so that portions of the program may be executed in a distributed manner.

[0150] In one embodiment, the computer-readable recording medium may be provided in the form of a non-transitory recording medium. The term "non-transitory" here means that the recording medium is a tangible device and not a transitory signal (e.g., electromagnetic waves). It does not distinguish between cases where data stored on the recording medium is stored semi-permanently and cases where data is stored temporarily. Furthermore, this is merely an example, and the recording medium may be modified to be a non-transitory recording medium.

[0151] The method according to one embodiment may be provided as a computer program product. The computer program product may be distributed in the form of a computer-readable medium (e.g., a CD-ROM), distributed online (e.g., uploaded or downloaded) through an application store, or distributed directly between two or more terminal devices. The method according to one embodiment may also be implemented as a computer program itself.

[0152] The present embodiment may be represented by functional block configurations and various processing steps. These functional blocks may be implemented by various hardware and / or software configurations that perform specific functions. For example, the embodiment may employ direct circuit configurations such as memory, processing, logic, look-up tables, etc., which may perform various functions under the control of one or more microprocessors or other control devices. Similarly, the present embodiment may be implemented in a programming or scripting language such as C, C++, Java, assembler, etc., including various algorithms implemented as a combination of data structures, processes, routines, or other programming configurations. Functional aspects may be implemented as algorithms that execute on one or more processors. Furthermore, the present embodiment may employ conventional techniques for electronic configuration, signal processing, and / or data processing. Terms like "mechanism," "element," "means," and "composition" can be used broadly and are not limited to mechanical or physical components. These terms can also encompass a series of software routines, such as those associated with a processor.

[0153] The above-described embodiments are merely examples, and other embodiments may be implemented within the scope of the claims set forth below.

Claims

1. A step of obtaining a noise level based on the cell voltage change amount of a selected battery cell selected from a slave including a plurality of battery cells; A step of obtaining a deviation of the selected battery cell based on a cell voltage average change amount, which is a difference between the cell voltage average values ​​of the selected battery cell for each of the current section and the previous section, a change amount average value, which is an average of the cell voltage average change amounts of the plurality of battery cells, and the noise level; A step of obtaining a final signal of the selected battery cell based on the above deviation; and A battery management method comprising a step of determining whether the selected battery cell is abnormal based on the level of the final signal and the first comparison result of the first threshold value.

2. In paragraph 1, The step of obtaining the above final signal is: A step of obtaining the slope of the deviation, which is the difference between the amount of change in the deviation and the amount of change in the average value of the deviation; and A battery management method comprising a step of obtaining the final signal corresponding to the above deviation and the above slope.

3. In paragraph 2, The step of obtaining the above final signal is: It further includes a step of obtaining a value obtained by dividing the above deviation by the noise reduction level as a noise reduction value, The step of obtaining the final signal corresponding to the above deviation and the above slope is: A battery management method for obtaining a value obtained by multiplying the above deviation, the above slope, and the above noise reduction value as the final signal.

4. In paragraph 2, The above deviation change amount is a battery management method, wherein the difference in deviation of the selected battery cell between the current section and the previous section is multiplied by the slope scale.

5. In paragraph 4, A battery management method, wherein the above average deviation value change amount is a value obtained by multiplying the difference between the average values ​​of the deviations of the plurality of battery cells for the current section and the previous section by a slope scale.

6. In paragraph 1, The step of determining whether the above selected battery cell is abnormal is: A step of obtaining a second comparison result by comparing a deviation ratio based on the first maximum and minimum values ​​of the above deviations with a second threshold value; and A battery management method, comprising a step of determining whether the selected battery cell is abnormal based on the first comparison result and the second comparison result.

7. In paragraph 6, The step of obtaining the second comparison result is as follows: A step of obtaining a second maximum value of the deviation excluding the first maximum value and a first ratio of the first maximum value; A step of obtaining a second ratio of one of the first maximum value and the second maximum value and the minimum value; and A battery management method comprising a step of obtaining the difference between the first ratio and the second ratio as the deviation ratio.

8. In paragraph 1, The step of obtaining the above noise level is: A step of obtaining a first operation value obtained by dividing the sum of squares of the cell voltage changes by the number of cell voltage changes; A step of obtaining a second operation value which is the square of the value obtained by dividing the sum of the cell voltage changes by the number of the cell voltage changes; A battery management method, comprising a step of obtaining a third operation value obtained by multiplying the root value of the difference between the first operation value and the second operation value and a noise scale as the noise level.

9. In paragraph 1, The step of obtaining the above deviation is: A step of obtaining, as a first operation value, the difference between the average cell voltage change amount of the selected battery cell for the current section and the average change amount of the plurality of battery cells for the previous section; A step of obtaining a second operation value as the difference between the change amount in the average cell voltage of the selected battery cell for the current section and the change amount average value of the plurality of battery cells for the current section; A step of obtaining a third operation value by dividing the sum of the first difference value and the second difference value by the average value of the change amount of the plurality of battery cells for the current section; and A battery management method, comprising a step of obtaining a fourth operation value obtained by dividing the third operation value by the noise level as the deviation.

10. An information acquisition interface for acquiring the cell voltage of each of the multiple battery cells included in the slave; and Obtaining a noise level based on the cell voltage change amount of the selected battery cell from the above slave, Obtain the deviation of the selected battery cell based on the difference in the cell voltage average value of the selected battery cell for each of the current section and the previous section, the variation average value which is the average of the cell voltage average value changes of the plurality of battery cells, and the noise level, Based on the above deviation, the final signal of the selected battery cell is obtained, A battery management device including a processor that determines whether the selected battery cell is abnormal based on the level of the final signal and the first comparison result of the first threshold value.

11. A computer-readable recording medium containing a program for executing the battery management method of paragraph 1 on a computer.

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