Apparatus and method for managing battery

Abstract

An apparatus and method for managing a battery includes a charger charging a battery including two or more battery cells connected in series, and a processor configured to control the charger to charge the battery at a first constant current in response to a quick charge request to the battery, and to control the charger to charge the battery at a second constant current in response to a quick charge request to the battery. When quick charging is performed, one of the voltages of the battery cells is monitored, and a charging characteristic of the battery is controlled according to an interval to which the cell voltage belongs in a dQ / dV curve.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2024 - 0012600, filed on January 26, 2024, the entire contents of which are incorporated herein for all purposes by this reference. Technical Field

[0003] The present invention relates to an apparatus and method for managing a battery, and more particularly, to a technique for charging a battery and diagnosing an abnormality of the battery. Background Art

[0004] Due to the diversity of electronic devices, the fields of use of batteries have increased. Recently, with the emergence of electric vehicles such as electric vehicles or hybrid electric vehicles, the use of batteries has increased.

[0005] As the battery usage time increases, it is not easy to overcome the limitation of the battery capacity, and battery charging problems appear. Fast charging schemes are widely used to quickly charge the battery, but as the charging speed increases, the durability of the battery decreases.

[0006] In addition, slowing down the charging speed of the battery to prevent deterioration of the battery durability may cause inconvenience to the user.

[0007] The information included in the background art of the present invention is only intended to enhance the understanding of the overall background of the present invention, and should not be regarded as an admission or any form of suggestion that this information constitutes prior art already known to those skilled in the art. Summary of the Invention

[0008] Aspects of the present invention are directed to providing an apparatus and method for managing a battery that does not reduce the durability of the battery without reducing the charging speed of the battery.

[0009] In addition, another aspect of the present invention provides an apparatus and method for managing a battery that is configured to diagnose an abnormality of the battery based on battery charging characteristics.

[0010] The technical problems solved by the present invention are not limited to the above problems, and those skilled in the art to which the present invention pertains will clearly understand any other technical problems not mentioned herein through the following description.

[0011] According to one aspect of the present invention, a device for managing a battery includes a charger and a processor. The charger charges a battery including two or more battery cells connected in series. The processor is configured to, in response to a fast charging request for the battery, control the charger to charge the battery with a first constant current, monitor one of the voltages of the battery cells during fast charging, and is configured to control the charging characteristics of the battery according to the interval in the dQ / dV curve to which the cell voltage belongs.

[0012] According to an exemplary embodiment of the present invention, the processor is configured to: during the interval of fast charging, determine whether the cell voltage reaches the phase change interval of the dQ / dV curve, and control the charger to charge the battery with a constant voltage in the phase change interval.

[0013] According to an exemplary embodiment of the present invention, the processor is configured to: determine the voltage interval including the cell voltage corresponding to the peak of the dQ / dV curve as the phase change interval.

[0014] According to an exemplary embodiment of the present invention, the processor may identify the maximum cell voltage at the entry time of the phase change interval and determine the magnitude of the constant voltage as the maximum cell voltage.

[0015] According to an exemplary embodiment of the present invention, the processor is configured to, after the phase change interval, control the charger to charge the battery based on a second constant current.

[0016] According to an exemplary embodiment of the present invention, the processor may identify the cut-off current corresponding to the current of the battery at the end time of the phase change interval and determine the magnitude of the second constant current within a range greater than or equal to the cut-off current and less than or equal to the first constant current.

[0017] According to an exemplary embodiment of the present invention, the processor may, in response to a slow charging request, identify the battery cell showing the maximum cell voltage, obtain the reference dQ / dV curve of the battery cell showing the maximum cell voltage, and update the dQ / dV curve based on the reference dQ / dV curve.

[0018] According to an exemplary embodiment of the present invention, the processor may exclude the update procedure of the phase change interval when the remaining capacity of the battery is greater than the reference remaining capacity.

[0019] According to an exemplary embodiment of the present invention, the processor may detect the peak of the reference dQ / dV curve, obtain the average dQ / dV curve based on the average voltage of the battery cell, and determine whether the battery is in an abnormal state based on the decrease amount of the peak of the reference dQ / dV curve compared to the peak of the average dQ / dV curve.

[0020] According to an exemplary embodiment of the present invention, the processor is configured to: determine that the battery is in an abnormal state based on that the total reduction amount of each peak of the reference dQ / dV curve compared with each peak of the average dQ / dV curve is greater than or equal to a first threshold.

[0021] According to an exemplary embodiment of the present invention, the processor is configured to: determine that the battery is in an abnormal state based on that at least one reduction amount in the reduction amounts of the peaks of the reference dQ / dV curve compared with the peaks of the average dQ / dV curve is greater than or equal to a second threshold.

[0022] According to an exemplary embodiment of the present invention, the processor is configured to: determine whether the battery is in an abnormal state based on the voltage corresponding to the peak of the reference dQ / dV curve compared with the voltage corresponding to the peak of the average dQ / dV curve.

[0023] According to another aspect of the present invention, a method for managing a battery can, in response to a fast charging request for a battery including a plurality of battery cells, control a charger to charge the battery with a first constant current, monitor one of the voltages of the battery cells during fast charging, and control the charging characteristics of the battery according to the interval in the dQ / dV curve to which the cell voltage belongs.

[0024] According to an exemplary embodiment of the present invention, controlling the charging characteristics may include: determining whether the cell voltage is included in the phase transition interval of the dQ / dV curve, and controlling the charger to charge the battery with a constant voltage in the phase transition interval.

[0025] According to an exemplary embodiment of the present invention, controlling the charger in the phase transition interval may include: identifying the maximum cell voltage at the entry time of the phase transition interval, and determining the magnitude of the constant voltage as the maximum cell voltage.

[0026] According to an exemplary embodiment of the present invention, the method may further include: after the phase transition interval, charging the battery based on a second constant current.

[0027] According to an exemplary embodiment of the present invention, charging the battery based on a second constant current may include: identifying a cut-off current corresponding to the current of the battery at the end time of the phase transition interval, and determining the magnitude of the second constant current within a range greater than or equal to the cut-off current and less than or equal to the first constant current.

[0028] According to an exemplary embodiment of the present invention, the method may further include: in response to a slow charging request, identifying the battery cell showing the maximum cell voltage, obtaining the reference dQ / dV curve of the battery cell showing the maximum cell voltage, and updating the dQ / dV curve based on the reference dQ / dV curve.

[0029] According to an exemplary embodiment of the present invention, the method may further include: detecting a peak of a reference dQ / dV curve, obtaining an average dQ / dV curve based on the average voltage of the battery cell, and determining whether the battery is in an abnormal state based on a decrease amount of the peak of the reference dQ / dV curve compared to the peak of the average dQ / dV curve.

[0030] According to an exemplary embodiment of the present invention, wherein determining whether the battery is in an abnormal state may include: determining whether the battery is in an abnormal state based on a voltage of a peak of the reference dQ / dV curve compared to a voltage of the peak that matches the average dQ / dV curve.

[0031] The method and apparatus of the present invention have other characteristics and advantages, which will be apparent from or will be described in detail in the accompanying drawings and subsequent detailed description incorporated herein. The accompanying drawings and detailed description together are used to explain specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a block diagram showing a connection relationship of a device for managing a battery according to an exemplary embodiment of the present invention;

[0033] Figure 2 is a block diagram showing a configuration of a device for managing a battery according to an exemplary embodiment of the present invention;

[0034] Figure 3 is a schematic diagram showing an example of a dQ / dV curve;

[0035] Figure 4 is a flowchart showing a method for managing a battery according to an exemplary embodiment of the present invention;

[0036] Figure 5 is a schematic diagram showing a battery charging scheme according to an exemplary embodiment of the present invention and a voltage of a battery cell according to the battery charging scheme;

[0037] Figure 6 is a schematic diagram showing a change in current of a battery cell during battery charging according to an exemplary embodiment of the present invention;

[0038] Figure 7 is a schematic diagram showing a change in voltage of a battery cell during battery charging according to an exemplary embodiment of the present invention;

[0039] Figure 8 is a schematic diagram showing a change in durability of a battery cell according to an exemplary embodiment of the present invention;

[0040] Figure 9 is a flowchart showing a method of managing a battery according to another exemplary embodiment of the present invention;

[0041] Figure 10 is a flowchart showing a method of diagnosing an abnormality of a battery according to an exemplary embodiment of the present invention;

[0042] Figure 11 is a block diagram showing a computing system according to an exemplary embodiment of the present invention.

[0043] It should be understood that the accompanying drawings are not drawn to scale and are merely schematic representations of the various features of the present invention for the purpose of illustrating the basic principles. The specific design features of the present invention disclosed herein, such as specific dimensions, orientations, positions, and configurations, will be determined in part by the particular application and use environment.

[0044] In the drawings, throughout the several views, like reference numerals refer to the same or equivalent parts of the present invention. DETAILED DESCRIPTION

[0045] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated and described in the accompanying drawings. Although the present invention will be described in conjunction with the exemplary embodiments of the present invention, it will be understood that this specification is not intended to limit the present invention to those exemplary embodiments. On the contrary, the present invention is intended to cover not only the exemplary embodiments of the present invention, but also various alternative forms, modifications, equivalents, and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0046] Hereinafter, various exemplary embodiments of the present invention will be described in detail with reference to the exemplary drawings. When adding reference numerals to the components of each drawing, it should be noted that even if shown in other drawings, the same or equivalent components are referred to by the same reference numerals. In addition, when it is determined that a detailed description of a related known configuration or function will interfere with the understanding of the exemplary embodiments of the present invention, the detailed description thereof will be omitted.

[0047] When describing the components of the exemplary embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only intended to distinguish the components from other components, and these terms do not limit the nature, order or sequence of the components. Unless otherwise defined, the terms used herein (including technical terms and scientific terms) include the same meanings as those commonly understood by those of ordinary skill in the art to which the present invention pertains. It will be further understood that terms such as those defined in common dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant field, and will not be interpreted as idealized or overly formal meanings unless explicitly defined as such herein.

[0048] The following will refer to Figures 1 to 11 describe the various exemplary embodiments of the present invention in detail.

[0049] Figure 1 is a block diagram showing the connection relationship of a device for managing a battery according to an exemplary embodiment of the present invention. Figure 2 is a block diagram showing the configuration of a device for managing a battery according to an exemplary embodiment of the present invention. Figure 3 is a schematic diagram showing an example of a dQ / dV curve.

[0050] Hereinafter, reference will be made to Figure 1 、 Figure 2 and Figure 3 describe a device for managing a battery according to an exemplary embodiment of the present invention.

[0051] Referring to Figure 1 , according to an exemplary embodiment of the present invention, a device BMU for managing a battery can be installed in a vehicle VEH and provide voltages to controllers 21, 22 and 23 in the vehicle. For example, the first controller 21 can provide a voltage to an external load 31. The second controller 22 can include a DC / DC converter for providing a voltage to a heater 32. The third controller 23 can include a DC / AC converter for providing a voltage to a motor 33 for driving the vehicle.

[0052] For this purpose, as Figure 2 shown, according to an exemplary embodiment of the present invention, a device BMU for managing a battery can include a battery 60, a communication device 70, sensor devices CMU1 to CMUn, and a processor 100.

[0053] The battery 60 can include n (n is a natural number of 2 or more) battery modules BM1 to BM n. Each of the battery modules BM1 to BM n can include a plurality of battery cells 10.

[0054] The sensor devices CMU1 to CMUn can be implemented as unit monitoring units corresponding one-to-one with the battery modules BM1 to BMn. The first CMU, CMU1, can detect the voltage of the first battery module BM1. In addition, the sensor devices CMU1 to CMUn can acquire battery state information.

[0055] The communication device 70 for communication between the sensor devices CMU1 to CMUn and the processor 100 can be implemented using a wired or wireless communication device.

[0056] For example, the communication device 70 can support short-range communication using at least one of Bluetooth, radio frequency identification (RFID), Infrared Data Association (IrDA), ultra-wideband (UWB), ZigBee, near field communication (NFC), Wi-Fi, Wi-Fi Direct, and wireless universal serial bus (USB) technology.

[0057] In addition, when the processor 100 is located outside the vehicle, the communication device 70 can communicate based on Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Code Division Multiple Access 2000 (CDMA2000), EV-DO (enhanced voice-data optimized or enhanced voice-data only), Wideband CDMA (WCDMA), High-Speed Downlink Packet Access (HSDPA), High-Speed Uplink Packet Access (HSUPA), Long-Term Evolution (LTE), Long-Term Evolution-Advanced (LTE-A), etc.

[0058] The charger 80 can be used to charge the battery 60 and can include a fast charger and a slow charger. The fast charger can quickly charge the battery 60 by directly supplying DC power to the charging plug of the vehicle. The slow charger can be an on-board charger (OBC) that converts the AC power supplied through the charging plug of the vehicle into DC power and supplies the DC power to the battery 60.

[0059] The processor 100 can identify a charging request for the battery 60 and control the charger 80 according to the charging request. The processor 100 can alternately perform constant current charging and constant voltage charging in response to a fast charging request. During the execution of constant current charging, the processor 100 can monitor one of the cell voltages of the battery 60 and control the charging characteristics of the battery 60 according to the interval in the dQ / dV curve to which the cell voltage belongs. For example, the processor 100 can charge the battery 60 with a constant voltage charging scheme in response to the cell voltage of the battery 60 reaching the phase change interval in the dQ / dV curve.

[0060] As Figure 3As shown, the dQ / dV curve can be a graph showing the voltage (V) according to dQ / dV, and can be referred to as a differential capacity characteristic curve. Figure 3 The dQ / dV curve of a ternary cathode material (NMC) battery containing nickel, manganese, and cobalt as main components can be displayed.

[0061] dQ / dV can be a value obtained by differentiating the charge capacity of battery cell 10 with respect to the voltage of battery cell 10. The dQ / dV curve can match dQ / dV with the voltage of battery cell 10.

[0062] The dQ / dV curve of battery cell 10 can include phase change intervals Ph1, Ph2, Ph3, and Ph4 of phase change. The first phase change interval Ph1 can be an interval in which C6 changes to LiCx. The second phase change interval Ph2, which is a phase change interval of NMC, can be an interval in which the hexagonal structure changes to the monoclinic structure. The third phase change interval Ph3 can be an interval of the phase in which H2 changes to H3. In the NMC battery, the fourth phase change interval Ph4 can be a stable interval.

[0063] In the dQ / dV curve, the first phase change interval Ph1, the second phase change interval Ph2, the third phase change interval Ph3, and the fourth phase change interval Ph4 can be intervals including the voltages at which peaks are generated. For example, the first phase change interval Ph1 can be a voltage interval including the first voltage V1 at which the first peak Pk1 is generated. The second phase change interval Ph2 can be a voltage interval including the second voltage V2 at which the second peak Pk2 is generated. The third phase change interval Ph3 can be a voltage interval including the third voltage V3 at which the third peak Pk3 is generated. The fourth phase change interval Ph4 can be a voltage interval including the fourth voltage V4 at which the fourth peak Pk4 is generated.

[0064] The dQ / dV curve can be determined in advance based on battery cell 10 before degradation.

[0065] The algorithm for operating the processor 100 can be stored in the memory 90. The memory 90 can include a hard disk drive, a flash memory, an electrically erasable programmable read-only memory (EEPROM), a static RAM (SRAM), a ferroelectric RAM (FRAM), a phase change RAM (PRAM), a magnetic RAM (MRAM), a dynamic random access memory (DRAM), a synchronous dynamic random access memory (SDRAM), a double data rate SDRAM (DDR-SDRAM), etc.

[0066] Figure 4 is a flowchart showing a method of managing a battery according to an exemplary embodiment of the present invention. Figure 5 is a schematic diagram showing a battery charging scheme according to an exemplary embodiment of the present invention and the voltage of a battery cell according to the battery charging scheme. Figure 4 shows byFigure 2 The processor-controlled program shown below. Hereinafter, reference will be made to Figure 2 , Figure 3 , Figure 4 and Figure 5 to describe a method for managing a battery according to an exemplary embodiment of the present invention.

[0067] In operation S410, the processor 100 may be configured to control the battery 60 to be charged with a first constant current A1 in response to a fast charging request for the battery 60.

[0068] Operation S410 may correspond to a first constant current charging interval CC1.

[0069] The first constant current A1 may be preset and may be determined based on the battery cell 10 in a non-degraded state.

[0070] In operation S420, the processor 100 may be configured to determine whether a phase change interval in the dQ / dV curve is reached.

[0071] The phase change interval may be preset and may be an interval including the voltage at which a peak occurs. The entry voltage of the phase change interval may be a voltage less than the voltage at which the peak occurs, and the end voltage of the phase change interval may be a voltage greater than the voltage at which the peak occurs. Alternatively, the phase change interval may be a voltage level from the voltage at which the peak occurs to a voltage with a specified margin.

[0072] In operation S430, when the voltage of the battery cell 10 reaches the phase change interval, the processor 100 may be configured to control the charger 80 to charge the battery 60 with a constant voltage.

[0073] For example, operation S430 may be a program executed when the voltage of the battery cell 10 reaches the first phase change interval Ph1. The voltage of the battery cell 10 may be the voltage of the battery cell 10 having the maximum voltage. That is, the first constant voltage charging interval CV1 may be a program executed when the maximum cell voltage reaches the lowest voltage in the first phase change interval Ph1.

[0074] In the first constant voltage charging interval CV1, the battery 60 may be charged with a first constant voltage, and the first constant voltage may be the maximum cell voltage obtained at the time of entering the first constant voltage charging interval CV1 and may be the lowest voltage in the first phase change interval Ph1.

[0075] As an entry condition for the first constant voltage charging interval CV1, the reason for checking the maximum cell voltage is to prevent the accelerated deterioration of the battery cell 10 with a higher resistance. The battery cell 10 with the maximum cell voltage can be estimated to have a larger internal resistance. According to an exemplary embodiment of the present invention, in order to prevent further deterioration of the battery cell 10 with a higher internal resistance, constant voltage charging can be performed when the maximum cell voltage reaches the phase change interval, and the charging current of the battery cell 10 with the maximum cell voltage in the phase change interval can be reduced.

[0076] According to an exemplary embodiment of the present invention, by slightly reducing the charging speed in the interval where the material of the battery cell 10 undergoes a phase change, side reactions can be reduced and the durability of the battery cell 10 can be improved.

[0077] In addition, after the phase change interval, the processor 100 can charge the battery 60 again with a constant current scheme. For example, the charging scheme of the battery 60 can be to enter the second constant current charging interval CC2 after the first constant voltage charging interval CV1. The end of the first constant voltage charging interval CV1 can be the time point when the maximum cell voltage reaches the maximum voltage in the first phase change interval Ph1.

[0078] To enter the second constant current charging interval CC2, the processor 100 can check the current of the battery 60 at the end time of the phase change interval. The processor 100 can be configured to determine the charging current of the second constant current charging interval CC2 based on the cut-off current Ass at the end time of the first phase change interval Ph1. For example, the processor 100 can be configured to determine the magnitude of the second constant current A2 within the range above the cut-off current A11 of the first phase change interval Ph1 and below the first constant current A1.

[0079] In this way, the processor 100 can alternately perform constant current charging and constant voltage charging.

[0080] For example, when the voltage of the battery cell 10 reaches the second phase change interval Ph2, the second constant voltage charging interval CV2 can be started. When the second phase change interval Ph2 ends, the processor 100 can charge the battery 60 based on the third constant current A3 in the third constant current charging interval CC3. The third constant current A3 can be determined within the range above the second cut-off current A21 and below the second constant current A2.

[0081] Furthermore, when the voltage of the battery cell 10 reaches the third phase change interval Ph3, a third constant voltage charging interval CV3 may be initiated. When the third phase change interval Ph3 ends, the processor 100 may charge the battery 60 using a fourth constant current A4 in a fourth constant current charging interval CC4. The fourth constant current A4 may be determined within a range greater than or equal to the third cut-off current A31 and less than or equal to the third constant current A3.

[0082] In addition, when the voltage of the battery cell 10 reaches the fourth phase change interval Ph4 , the fourth constant voltage charging interval CV4 may start.

[0083] Figure 6 is a schematic diagram illustrating current changes of battery cells during a battery charging process according to an exemplary embodiment of the present invention. Figure 7 is a schematic diagram illustrating voltage changes of battery cells during a battery charging process according to an exemplary embodiment of the present invention. Figure 8 is a schematic diagram illustrating changes in durability of a battery cell according to an exemplary embodiment of the present invention. Figure 6 、 Figure 7 and Figure 8 Embodiments of the present invention and comparative examples are shown.

[0084] refer to Figure 6 and Figure 7 According to an exemplary embodiment of the present invention, the battery 60 can be charged based on a constant current in the constant current charging intervals CC1, CC2, CC3 and CC4, and the battery 60 can be charged based on a constant voltage in the constant voltage charging intervals CV1, CV2, CV3 and CV4.

[0085] Since the battery 60 is charged at a constant voltage in the constant voltage charging sections CV1 , CV2 , CV3 , and CV4 , the charging current can be reduced and the charging speed can be lowered.

[0086] Since the constant voltage charging intervals CV1, CV2, CV3, and CV4 are intervals where the internal material of the battery 60 undergoes phase change, side reactions may be active and the durability of the battery cell 10 may be deteriorated. According to an exemplary embodiment of the present invention, the charging speed of the battery 60 in the phase change intervals Ph1, Ph2, Ph3, and Ph4 can be slightly reduced while suppressing side reactions, thereby improving the durability of the battery cell 10.

[0087] In addition, according to an exemplary embodiment of the present invention, since the charging current during the constant current charging period is determined to be greater than the current value at the end of the previous constant voltage charging period, the battery 60 can be charged with a charging current higher than that in the charging scheme of the comparative example. That is, during the constant current charging period, the charging speed slightly reduced during the constant voltage charging period can be compensated for.

[0088] As Figure 8 shown, according to an exemplary embodiment of the present invention, even if the cycle of charging the battery 60 is repeated, the charging capacity of the battery 60 can be maintained at a predetermined level.

[0089] Figure 9 is a flowchart showing a method of managing a battery according to another exemplary embodiment of the present invention. Figure 9 It can show a program controlled by the Figure 2 shown processor. Hereinafter, a method of managing a battery according to an exemplary embodiment of the present invention will be described with reference to Figure 9 the following.

[0090] In operation S901, when there is a charging request, the processor 100 can be configured to determine whether the charging request is a fast charging request or a slow charging request.

[0091] In operation S903, in response to the fast charging request, the processor 100 can load a charging curve.

[0092] As Figure 5 shown, the charging curve can include entry conditions for constant current charging intervals CC1, CC2, CC3, and CC4 and constant voltage charging intervals CV1, CV2, CV3, and CV4. For example, the charging curve can include voltage levels determined in each of the phase change intervals Ph1, Ph2, Ph3, and Ph4 in order to enter the constant voltage charging intervals CV1, CV2, CV3, and CV4.

[0093] The charging curve can be determined based on the Figure 3 shown dQ / dV curve of the battery cell 10.

[0094] In operation S905, the processor 100 can control the first charger 80 based on the charging curve so as to charge the battery 60.

[0095] In operations S901 and S907, in response to the charging request being a slow charging request, the processor 100 can be configured to determine whether the SOC value of the battery 60 is less than a reference SOC.

[0096] In operation S909, in response to the SOC value of the battery 60 being less than the reference SOC value, the charging state information of the reference battery cell can be stored. The reference battery cell can be the battery cell 10 presenting the maximum cell voltage. The charging state information for obtaining the dQ / dV curve can include voltage information and charge capacity information.

[0097] In operation S911, the processor 100 can obtain a reference dQ / dV curve based on the charging state information of the reference battery cell.

[0098] For example, the processor 100 can obtain the reference dQ / dV curve by matching the value obtained by differentiating the charge capacity of the reference battery cell with respect to voltage with the voltage of the reference battery cell.

[0099] In operation S913, the processor 100 can update the charging curve based on the reference dQ / dV curve.

[0100] Updating the charging curve can include resetting the program of the constant current charging interval based on the peak of the reference dQ / dV curve. For example, when the difference between the voltage at which the peak of the reference dQ / dV curve appears and the voltage at which the peak of the preset dQ / dV curve appears is greater than or equal to the threshold voltage, the processor 100 can reset the constant current charging interval.

[0101] In operation S915, the processor 100 can perform slow charging based on the SOC value of the battery 60 being greater than or equal to the reference SOC.

[0102] Operation S915 can include skipping the programs of operations S909 to S911. That is, based on the SOC value of the battery 60 being greater than or equal to the reference SOC value, the processor 100 can omit the program of updating the charging curve.

[0103] Therefore, operation S913 of updating the charging curve excludes the case where the battery 60 is fast charged or the SOC value of the battery 60 is greater than or equal to the reference SOC. This is because when the SOC value of the battery 60 is low and the battery 60 is charged at a low charging rate (C-rate), the peak of the phase change interval can be obtained more clearly. Therefore, the reference SOC can be determined to be lower than the level at which the peak of the phase change interval can be obtained more clearly.

[0104] In operation S917, the processor 100 can further execute a program for diagnosing whether the battery 60 is abnormal based on the reference dQ / dV curve.

[0105] For example, the processor 100 can diagnose whether the battery 60 is abnormal based on the reference dQ / dV curve and the average dQ / dV curve of the battery 60.

[0106] The following will be based onFigure 10 To explain the detailed procedure of operation S917.

[0107] Figure 10 It is a flowchart showing a method for diagnosing battery anomalies according to an exemplary embodiment of the present invention.

[0108] Refer to Figure 10 , in operation S1001, the processor 100 may record the voltage of the battery 60 and the charge capacity of the battery 60.

[0109] In operation S1003, the processor 100 may obtain the average dQ / dV curve of the battery cell 10 based on the voltage of the battery 60 and the charge capacity of the battery 60. The average dQ / dV curve may be obtained based on the average cell voltage and the average charge capacity.

[0110] In operation S1005, the processor 100 may be configured to determine the amount of decrease in the peak of the average dQ / dV curve compared to the peak of the reference dQ / dV curve.

[0111] An example of determining the amount of decrease in the peak of the dQ / dV curve will be described based on Table 1 below.

[0112] The following Table 1 shows the amount of decrease in the peak of the reference dQ / dV curve compared to the average dQ / dV curve.

[0113] [Table 1]

[0114]

[0115] In Table 1, Pk1a may be the peak of the first phase transition interval of the average dQ / dV curve. Pk2a may be the peak of the second phase transition interval of the average dQ / dV curve. Pk3a may be the peak of the third phase transition interval of the average dQ / dV curve. Pk4a may be the peak of the fourth phase transition interval of the average dQ / dV curve.

[0116] Pk1r may be the peak of the first phase transition interval of the reference dQ / dV curve. Pk2r may be the peak of the second phase transition interval of the reference dQ / dV curve. Pk3r may be the peak of the third phase transition interval of the reference dQ / dV curve. Pk4r may be the peak of the fourth phase transition interval of the reference dQ / dV curve.

[0117] The peak reduction amount can be the peak reduction amount in each phase transition interval. For example, the first peak reduction amount can be obtained by subtracting the peak of the first phase transition interval of the average dQ / dV curve from the peak of the first phase transition interval of the reference dQ / dV curve. That is, the processor 100 can be configured to determine Pk1a - Pk1r and obtain the first peak reduction amount. Similarly, the processor 100 can obtain the second peak reduction amount based on Pk2a to Pk2r, the third peak reduction amount based on Pk3a to Pk3r, and the fourth peak reduction amount based on Pk4a to Pk4r.

[0118] In operations S1007 and S1009, the processor 100 can be configured to determine that the battery 60 is defective based on the total peak reduction amount being greater than or equal to the first threshold.

[0119] For example, the processor 100 can be configured to determine that the battery 60 is abnormal based on the sum of the first peak reduction amount, the second peak reduction amount, the third peak reduction amount, and the fourth peak reduction amount being greater than or equal to the first threshold. The processor 100 can be configured to determine that a large amount of the active material in the battery has been lost overall when the sum of the peak reduction amounts exceeds a specified level.

[0120] In operation S1011, the processor 100 can be configured to determine that the battery 60 is abnormal based on at least one of the multiple peak reduction amounts being greater than or equal to the second threshold.

[0121] For example, the processor 100 can be configured to determine that the state where the first peak reduction amount has decreased by more than a specified amount is a state where the deformation and loss of the negative electrode active material are greater than those of the positive electrode active material.

[0122] In addition, the processor 100 can be configured to determine that oxygen detachment of the positive electrode active material has occurred when the fourth peak reduction amount has decreased by more than a specified amount. It can be determined that the fourth peak Pk4 has been forcibly generated in the NMC battery in the Ni abnormal state, and in the state where the reduction amount of the fourth peak Pk4 is large, the oxygen detachment is stronger, resulting in Li decay.

[0123] In addition, in addition to Figure 10 the exemplary embodiments shown, based on the change amount of the voltage that matches the peak of the reference dQ / dV curve compared to the voltage that matches the peak of the average dQ / dV curve, the processor 100 can be configured to determine whether the battery 60 is abnormal.

[0124] For this purpose, as Figure 3 shown, the processor 100 can identify the first to fourth voltages V1, V2, V3, and V4 that respectively cause the peaks.

[0125] The processor 100 can be configured to determine whether the first voltage V1 in the reference dQ / dV curve is shifted compared to the first voltage V1 in the average dQ / dV curve. The processor 100 can be configured to determine that the battery 60 is abnormal when the first voltage V1 in the reference dQ / dV curve is greater than or equal to a third threshold compared to the first voltage V1 in the average dQ / dV curve. Similarly, when the second to fourth voltages V2, V3, and V4 in the reference dQ / dV curve are greater than or equal to the third threshold compared to each of the second to fourth voltages V2, V3, and V4 in the average dQ / dV curve, the processor 100 can determine that the battery 60 is abnormal.

[0126] The processor 100 can be configured to determine that the positive-negative ratio of the battery 60 is misaligned when the voltage deviation at which a peak occurs is higher than a specified level. For example, when irreversible Li increases inside the negative electrode, the negative electrode voltage may increase, so that the processor 100 can be configured to determine that the peak is shifted due to the shift of the negative electrode voltage.

[0127] Figure 11 is a block diagram showing a computing system according to an exemplary embodiment of the present invention.

[0128] Reference Figure 11 , the computing system 1000 can include at least one processor 1100, a memory 1300, a user interface input device 1400, a user interface output device 1500, a storage device 1600, and a network interface 1700 connected via a bus 1200.

[0129] The processor 1100 can be a central processing unit (CPU) or a semiconductor device that processes instructions stored in the memory 1300 and / or the storage device 1600. The memory 1300 and the storage device 1600 can include various types of volatile or non-volatile storage media. For example, the memory 1300 can include a read-only memory (ROM) and a random access memory (RAM).

[0130] Therefore, the processes of the methods or algorithms described in connection with the exemplary embodiments of the present invention can be directly implemented by hardware, software modules, or a combination thereof executed by the processor 1100. The software modules can be present on a storage medium (i.e., the memory 1300 and / or the storage device 1600), such as RAM, flash memory, ROM, EPROM, EEPROM, registers, a hard disk, a solid state drive (SSD), a removable disk, or a CD-ROM.

[0131] An exemplary storage medium is coupled to the processor 1100, and the processor 1100 can read information from the storage medium and can write information to the storage medium. In another approach, the storage medium may be integrated with the processor 1100. The processor and the storage medium may be present in an application specific integrated circuit (ASIC). The ASIC may be present within a user terminal. In another approach, the processor and the storage medium may be present as separate components within the user terminal.

[0132] According to an exemplary embodiment of the present invention, by reducing side reactions in the phase change interval of the materials inside the battery, the cause of durability degradation during battery charging can be reduced.

[0133] In addition, according to an exemplary embodiment of the present invention, an abnormal state of the battery can be diagnosed based on the dQ / dV curve according to battery charging.

[0134] In addition, various effects directly or indirectly recognized through this specification may be provided.

[0135] Although the exemplary embodiments of the present invention have been described for illustrative purposes, those skilled in the art should understand that various modifications, additions, and substitutions can be made without departing from the scope and spirit of the present invention.

[0136] In addition, terms such as "unit" and "module" included in the specification represent units for performing at least one function or operation, which can be implemented by hardware, software, or a combination thereof.

[0137] In the flowcharts described with reference to the accompanying drawings, the flowcharts can be executed by a controller or a processor. The order of operations in the flowcharts can be changed, multiple operations can be combined, or any operation can be split, and a specific operation may not be executed. In addition, the operations in the flowcharts can be executed sequentially, but not necessarily sequentially. For example, the order of operations can be changed, and at least two operations can be executed in parallel.

[0138] Hereinafter, hardware being operably coupled may include direct and / or indirect connections between hardware established in a wired and / or wireless manner.

[0139] In an exemplary embodiment of the present invention, a vehicle may be referred to based on a concept including various transportation means. In some cases, a vehicle may be interpreted based on a concept including not only various land transportation means (such as cars, motorcycles, large trucks, and buses) traveling on roads but also various transportation means such as airplanes, drones, ships, etc.

[0140] For the sake of convenient explanation and precise definition of the appended claims, the terms "upper", "lower", "inner", "outer", "above", "below", "upward", "downward", "front", "rear", "back", "inner side", "outer side", "inwardly", "outwardly", "internal", "external", "inner lateral", "outer lateral", "forward" and "backward" are used to describe the features of the exemplary embodiments with reference to the positions of these features shown in the accompanying drawings. It will be further understood that the term "connected" or its derivatives refers to both direct connection and indirect connection.

[0141] The term "and / or" may include combinations of multiple related listed items or any one of multiple related listed items. For example, "A and / or B" includes all three cases such as "A", "B", and "A and B".

[0142] In the exemplary embodiments of the present invention, "at least one of A and B" may refer to "at least one of A or B" or "at least one of the combination of at least one of A and B". In addition, "one or more of A and B" may refer to "one or more of A or B" or "one or more of the combination of one or more of A and B".

[0143] In this specification, unless otherwise specified, singular expressions include plural expressions.

[0144] In the exemplary embodiments of the present invention, it should be understood that terms such as "comprising" or "having" are intended to indicate the presence of the features, numerical values, steps, operations, elements, components or combinations thereof described in the specification, and do not exclude the possibility of adding or existing one or more other features, numerical values, steps, operations, elements, components or combinations thereof.

[0145] According to the exemplary embodiments of the present invention, components may be combined with each other to form one, or some components may be omitted.

[0146] The foregoing description of specific exemplary embodiments of the present invention has been presented for purposes of illustration and description. The description is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and changes are possible in light of the above teachings. The exemplary embodiments were chosen and described to explain specific principles of the invention and its practical application, so that others skilled in the art can implement and utilize the various exemplary embodiments of the invention, as well as various alternative forms and modifications thereof. The scope of the present invention is intended to be defined by the appended claims and their equivalents.

Claims

1. A device for managing a battery, the device comprising: A charger configured to charge a battery including two or more battery cells connected in series; And A processor operably connected to the charger and configured to: In response to a fast charging request for the battery, control the charger to charge the battery with a first constant current, During fast charging, determine one of the cell voltages of the two or more battery cells, Control the charging characteristics of the battery according to the interval in the dQ / dV curve to which the cell voltage belongs.

2. The device for managing a battery according to claim 1, wherein, The processor is further configured to: During the interval of fast charging, determine whether the cell voltage is in the phase change interval of the dQ / dV curve; In the phase change interval, control the charger to charge the battery with a constant voltage.

3. The device for managing a battery according to claim 2, wherein, The processor is further configured to: determine the voltage interval including the cell voltage corresponding to the peak of the dQ / dV curve as the phase change interval.

4. The device for managing a battery according to claim 2, wherein, The processor is further configured to: Identify the maximum cell voltage at the entry time of the phase change interval; Determine the magnitude of the constant voltage as the maximum cell voltage.

5. The device for managing a battery according to claim 2, wherein, The processor is further configured to: after the phase change interval, control the charger to charge the battery based on a second constant current.

6. The device for managing a battery according to claim 5, wherein, The processor is further configured to: Identify the cut-off current corresponding to the current of the battery at the end time of the phase change interval; Determine the magnitude of the second constant current within a range greater than or equal to the cut-off current and less than the first constant current.

7. The device for managing a battery according to claim 1, wherein, The processor is further configured to: In response to a slow charging request, determine the battery cell showing the maximum cell voltage among the two or more battery cells; Obtain the reference dQ / dV curve of the battery cell showing the maximum cell voltage; Update the dQ / dV curve based on the reference dQ / dV curve.

8. The apparatus for managing a battery according to claim 7, wherein, The processor is further configured to: based on determining that the remaining capacity of the battery is greater than the reference remaining capacity, exclude the update procedure for the phase change interval.

9. The apparatus for managing a battery according to claim 7, wherein, The processor is further configured to: Detect the peak of the reference dQ / dV curve; Obtain the average dQ / dV curve based on the average voltage of the two or more battery cells; Determine whether the battery is in an abnormal state based on the decrease amount of the peak of the reference dQ / dV curve compared to the peak of the average dQ / dV curve.

10. The device for managing a battery according to claim 9, wherein, The processor is further configured to: based on the total decrease amount of each peak of the reference dQ / dV curve compared to each peak of the average dQ / dV curve being greater than or equal to a first threshold, determine that the battery is in an abnormal state.

11. The device for managing a battery according to claim 9, wherein, The processor is further configured to: based on at least one decrease amount of the decrease amount of the peak of the reference dQ / dV curve compared to the peak of the average dQ / dV curve being greater than or equal to a second threshold, determine that the battery is in an abnormal state.

12. The device for managing a battery according to claim 9, wherein, The processor is further configured to: determine whether the battery is in an abnormal state based on the voltage corresponding to the peak of the reference dQ / dV curve compared to the voltage corresponding to the peak of the average dQ / dV curve.

13. A method for managing a battery, the method comprising: In response to a fast charging request for a battery including a plurality of battery cells, a charger operably connected to a processor is controlled by the processor to charge the battery with a first constant current; During fast charging, a processor determines one of the cell voltages of the plurality of battery cells; The processor controls the charging characteristics of the battery according to the interval to which the cell voltage belongs in the dQ / dV curve.

14. The method according to claim 13, wherein Controlling the charging characteristics of the battery includes: Determining whether the cell voltage is included in the phase change interval of the dQ / dV curve; During the phase change interval, controlling the charger to charge the battery with a constant voltage.

15. The method according to claim 14, wherein, Controlling the charger during the phase change interval includes: Determining the maximum cell voltage at the entry time of the phase change interval; Determining the magnitude of the constant voltage as the maximum cell voltage.

16. The method according to claim 14, further comprising: After the phase change interval, charging the battery based on a second constant current.

17. The method according to claim 16, wherein, Charging the battery based on a second constant current includes: Identifying a cut-off current corresponding to the current of the battery at the end time of the phase change interval; Determining the magnitude of the second constant current within a range greater than or equal to the cut-off current and less than the first constant current.

18. The method according to claim 13, further comprising: In response to a slow charging request, a processor identifies the battery cell among the plurality of battery cells that exhibits the maximum cell voltage; Obtaining a reference dQ / dV curve of the battery cell that exhibits the maximum cell voltage; Updating the dQ / dV curve based on the reference dQ / dV curve.

19. The method according to claim 18, further comprising: Detecting a peak of the reference dQ / dV curve; Obtaining an average dQ / dV curve based on the average voltage of the plurality of battery cells; Determining whether the battery is in an abnormal state based on the amount of decrease in the peak of the reference dQ / dV curve compared to the peak of the average dQ / dV curve.

20. The method according to claim 19, wherein, Determining whether the battery is in an abnormal state includes: determining whether the battery is in an abnormal state based on the voltage corresponding to the peak of the reference dQ / dV curve compared to the voltage corresponding to the peak of the average dQ / dV curve.

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