Method and apparatus for diagnosing battery abnormality of eco-friendly vehicle

Abstract

A method and apparatus for diagnosing a battery abnormality of an eco-friendly vehicle may include incrementing a count value based on a battery cell balance start voltage deviation and a battery cell balance end voltage deviation, the counter value and an identifier or identification number of a battery cell having the minimum voltage among a plurality of battery cells forming a battery module of the vehicle are stored, and a battery cell abnormality is detected based on the counter value and the identifier or identification number of the battery cell having the minimum voltage. The battery cell balance start voltage deviation is the voltage deviation of the plurality of battery cells at the start of a battery cell balance mode for adjusting the voltage deviation of the plurality of battery cells, and the battery cell balance end voltage deviation is the voltage deviation of the plurality of battery cells at the end of the battery cell balance mode.

Description

Technical Field

[0001] The present invention relates to a battery management system, and more particularly, to a method and apparatus for diagnosing battery anomalies in an eco-friendly vehicle. Background Art

[0002] Eco-friendly vehicles such as hybrid electric vehicles (HEVs), plug-in HEVs, electric vehicles (EVs), etc. are provided with a battery as a storage device, and the battery is configured to store electrical energy to drive an electric motor. Such eco-friendly vehicles are provided with a high-voltage battery, which is different from the low-voltage battery provided in a conventional internal combustion engine vehicle.

[0003] Since such a high-voltage battery is configured to have a higher energy density, dangerous situations such as fires may occur even due to minor quality problems. For this reason, the safety of the battery becomes more important. Although monitoring logic for battery safety is also applied in mass-produced electric vehicles, it is still insufficient in preventing accidents by pre-detecting battery anomalies.

[0004] Therefore, a technology capable of preventing accidents by pre-detecting battery anomaly symptoms is needed.

[0005] The information included in this background art of the present invention is only for enhancing the understanding of the general background art of the present invention, and should not be regarded as an admission or any form of suggestion that this information constitutes the prior art known to those skilled in the art. Summary of the Invention

[0006] Aspects of the present invention are directed to providing a technology configured to pre-detect anomaly symptoms of a battery.

[0007] Another object of the present invention is to provide a logic configured to diagnose a battery cell with anomaly symptoms by using a cell balancing technique for balancing voltage deviation of a high-voltage battery, thereby performing high-voltage battery diagnosis.

[0008] It should be understood that the technical problems to be solved by the present invention are not limited to the above technical problems, and those skilled in the art to which the present invention pertains will more clearly understand other technical problems from the following description.

[0009] According to one aspect of the present invention, the above and other objects can be achieved by providing a method for diagnosing battery anomalies in an eco-friendly vehicle, the method comprising: incrementing a count value based on a battery cell balance start voltage deviation and a battery cell balance end voltage deviation, and storing the count value and the identifier or identification number of the battery cell having the minimum voltage among a plurality of battery cells forming a battery module of the vehicle, wherein the battery cell balance start voltage deviation is the voltage deviation of the plurality of battery cells at the start of a battery cell balance mode for adjusting the voltage deviation of the plurality of battery cells, and the battery cell balance end voltage deviation is the voltage deviation of the plurality of battery cells at the end of the battery cell balance mode; detecting a battery cell anomaly based on the count value and the identifier or identification number of the battery cell having the minimum voltage.

[0010] Detecting a battery cell anomaly may include: detecting a battery cell anomaly based on whether there is a repeated identifier or identification number of the battery cell having the minimum voltage at different count values and whether the current count value is not less than a threshold count value.

[0011] The method may further comprise: starting a battery cell balance mode and storing the battery cell balance start voltage deviation; ending the battery cell balance mode based on the voltage deviation of the plurality of battery cells or the elapsed time, and storing the battery cell balance end voltage deviation.

[0012] Storing the count value and the identifier or identification number of the battery cell having the minimum voltage among the plurality of battery cells may include: incrementing the count value when the battery cell balance end voltage deviation is not less than a value obtained by adding the battery cell balance start voltage deviation and a threshold voltage drop; storing the count value and the identifier or identification number of the battery cell having the minimum voltage among the plurality of battery cells.

[0013] The count value may be initially set to "0" and incremented by "1".

[0014] The voltage deviation of the plurality of battery cells may be the difference between the average voltage of the plurality of battery cells and the voltage of the battery cell having the minimum voltage among the plurality of battery cells.

[0015] During the process of starting the battery cell balance mode and storing the battery cell balance start voltage deviation, when the difference between the average voltage of the plurality of battery cells and the voltage of the battery cell having the minimum voltage among the plurality of battery cells is not less than a first threshold, the battery cell balance mode may start.

[0016] During the process of ending the battery cell balance mode and storing the battery cell balance end voltage deviation, when the state where the difference between the average voltage of the plurality of battery cells and the voltage of the battery cell having the minimum voltage among the plurality of battery cells is not greater than a second threshold is maintained for a first threshold period of time, the battery cell balance mode may end.

[0017] In the process of ending the cell balancing mode and storing the cell balancing end voltage deviation, the cell balancing mode may end when a predetermined period of time has elapsed since the start time of the cell balancing mode.

[0018] In the process of starting the cell balancing mode and storing the cell balancing start voltage deviation, when, after the start of the cell balancing mode, the temperature of the cell having the minimum voltage among the plurality of cells is higher than a first threshold temperature and the state of charge (SOC) value of the battery is not less than a first threshold ratio, the cell balancing start voltage deviation may be stored.

[0019] In the process of ending the cell balancing mode and storing the cell balancing end voltage deviation, when, after the end of the cell balancing mode, the temperature of the cell having the minimum voltage among the plurality of cells is higher than a second threshold temperature and the state of charge (SOC) value of the battery is not less than a second threshold ratio, the cell balancing end voltage deviation may be stored.

[0020] The method may further include: when there are repeated identifiers or identification numbers of the cell having the minimum voltage at different count values and the current count value is not less than a threshold count value, sending a warning message to the driver and controlling the vehicle.

[0021] According to another aspect of the present invention, there is provided an apparatus for diagnosing a battery abnormality of an eco-friendly vehicle, the apparatus including: a battery configured to store electrical energy for driving the vehicle, the battery including a plurality of cells; a sensor unit including a voltage sensor configured to detect the voltages of the plurality of cells; and a battery management unit operably connected to the sensor unit and configured to: increment a count value based on the cell balancing start voltage deviation and the cell balancing end voltage deviation, store the count value and the identifier or identification number of the cell having the minimum voltage among the plurality of cells, and detect a cell abnormality based on the count value and the identifier or identification number of the cell having the minimum voltage, where the cell balancing start voltage deviation is the voltage deviation of the plurality of cells at the start of the cell balancing mode for adjusting the voltage deviation of the plurality of cells, and the cell balancing end voltage deviation is the voltage deviation of the plurality of cells at the end of the cell balancing mode.

[0022] The battery management unit may detect a cell abnormality based on whether there are repeated identifiers or identification numbers of the cell having the minimum voltage at different count values and whether the current count value is not less than a threshold count value.

[0023] The battery management unit can start the cell balancing mode and can store the cell balancing start voltage deviation. The battery management unit can end the cell balancing mode based on the voltage deviation of multiple cells or the elapsed time and can store the cell balancing end voltage deviation.

[0024] The battery management unit can increment the count value when the cell balancing end voltage deviation is not less than the value obtained by adding the cell balancing start voltage deviation and the threshold voltage drop, and can store the count value and the identifier or identification number of the cell with the minimum voltage among the multiple cells.

[0025] The count value can be initially set to "0" and can be incremented by "1".

[0026] The voltage deviation of multiple cells can be the difference between the average voltage of multiple cells and the voltage of the cell with the minimum voltage among the multiple cells.

[0027] When the difference between the average voltage of multiple cells and the voltage of the cell with the minimum voltage among the multiple cells is not less than the first threshold, the battery management unit can start the cell balancing mode.

[0028] When the state where the difference between the average voltage of multiple cells and the voltage of the cell with the minimum voltage among the multiple cells is not greater than the second threshold holds for the first threshold time period, the battery management unit can end the cell balancing mode.

[0029] When a predetermined time period has elapsed since the start of the cell balancing mode, the battery management unit can end the cell balancing mode.

[0030] When, after the start of the cell balancing mode, the temperature of the cell with the minimum voltage among the multiple cells is higher than the first threshold temperature and the state of charge (SOC) value of the battery is not less than the first threshold ratio, the battery management unit can store the cell balancing start voltage deviation.

[0031] When, after the end of the cell balancing mode, the temperature of the cell with the minimum voltage among the multiple cells is higher than the second threshold temperature and the state of charge (SOC) value of the battery is not less than the second threshold ratio, the battery management unit can store the cell balancing end voltage deviation.

[0032] When there are repeated identifiers or identification numbers of the cell with the minimum voltage at different count values and the current count value is not less than the threshold count value, the battery management unit can send a warning message to the driver and is configured to control the vehicle.

[0033] According to the above embodiments of the present invention, abnormal symptoms of the battery can be detected in advance.

[0034] In addition, a logic is provided that is configured to diagnose a battery cell with abnormal symptoms by utilizing a cell balancing technique for balancing voltage deviations of a high-voltage battery, thereby performing high-voltage battery diagnosis.

[0035] In addition, accidents can be prevented by enhancing the high-voltage battery monitoring function and the safety of an eco-friendly vehicle can be enhanced.

[0036] The effects that can be achieved in the exemplary embodiments of the present invention are not limited to the above effects, and other effects of the present invention that have not been described will be more clearly understood by those skilled in the art from the following detailed description.

[0037] The method and apparatus of the present invention have other features and advantages that will be apparent from or will be described in detail in the accompanying drawings and the following detailed description, which are incorporated herein and together serve to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 An example of a graph showing cell balancing of a conventional eco-friendly vehicle is shown;

[0039] Figure 2 is a block diagram schematically showing a battery abnormality diagnosis device according to an exemplary embodiment of the present invention;

[0040] Figure 3 An example of a severe voltage deviation due to a detectable abnormal battery cell according to an exemplary embodiment of the present invention is shown;

[0041] Figure 4 is a flowchart showing a method of storing voltage deviations and SoC between battery cells at the start of a battery cell balancing mode according to an exemplary embodiment of the present invention;

[0042] Figure 5A and Figure 5B is a flowchart showing a method of storing voltage deviations and SoC between battery cells at the end of a battery cell balancing mode according to an exemplary embodiment of the present invention; and

[0043] Figure 6 is a flowchart showing a battery abnormality diagnosis method according to an exemplary embodiment of the present invention.

[0044] It will be understood that the drawings are not necessarily drawn to scale, presenting a somewhat simplified representation of various features illustrating the basic principles of the present invention. The specific design features of the present invention as included herein (including, for example, specific dimensions, orientations, positions, and shapes) will be determined in part by the particular application and use environment.

[0045] In the accompanying drawings, throughout the several views of the drawings, like reference numerals refer to the same or equivalent parts of the present invention. Detailed Embodiments

[0046] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. Although the present invention will be described in conjunction with the exemplary embodiments of the present invention, it should be understood that this description is not intended to limit the present invention to those exemplary embodiments. On the other hand, the present invention is intended to cover not only the exemplary embodiments of the present invention, but also various alternative embodiments, modified embodiments, equivalent embodiments, and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0047] Hereinafter, various exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or similar elements will be denoted by the same reference numerals regardless of the reference numerals in the drawings and their repeated description will be omitted. Although the suffixes “module” or “unit” are used for the constituent elements described in the following description, this is only for convenience of description of the specification. The suffix itself does not have a meaning or function for distinguishing the constituent elements using the suffix from those not using the suffix. In the following description of the exemplary embodiments of the present invention, when the detailed description of the known functions and configurations incorporated herein may obscure the subject matter of the exemplary embodiments of the present invention, the detailed description will be omitted. In addition, the exemplary embodiments of the present invention will be more clearly understood through the accompanying drawings, and it should be understood that all modified embodiments, equivalent embodiments, and alternative embodiments that do not depart from the spirit and technical scope of the present invention are included in the exemplary embodiments of the present invention.

[0048] It should be understood that although the terms “first,” “second,” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

[0049] In the case where an element is “connected” or “coupled” to another element, it should be understood that the element can be directly connected or coupled to the other element, or there may be other elements therebetween. On the contrary, in the case where an element is “directly connected” or “directly coupled” to another element, it should be understood that there are no other elements therebetween.

[0050] Unless otherwise clearly used, singular expressions include plural meanings.

[0051] In this specification, terms such as "comprising" and "including" are intended to indicate the presence of features, values, steps, operations, elements, components, or combinations thereof, and do not preclude the presence or addition of other features, values, steps, operations, elements, components, or any combination thereof.

[0052] Figure 1 An example of a graph showing the balancing of battery cells in a conventional environmentally friendly vehicle is shown.

[0053] Cell balancing means that when the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage among multiple cells is not less than a predetermined threshold, the voltage deviation is controlled to decrease by consuming a small current starting from the cells with a voltage higher than that of the cell with the minimum voltage.

[0054] Reference Figure 1 , when the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage among the multiple cells forming the battery module is not less than the predetermined threshold for starting the cell balancing mode, the battery enters or starts the cell balancing mode for reducing the voltage deviation.

[0055] In this case, the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage at the start of the cell balancing mode can be defined as ΔV 初始 .

[0056] In the cell balancing mode, the current of the cells with a voltage higher than that of the cell with the minimum voltage is slightly consumed, thereby reducing the voltage deviation between the cells forming the battery module.

[0057] In this case, after a predetermined period of time in the cell balancing mode, when the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage is not greater than the predetermined threshold for ending the cell balancing mode, the cell balancing mode ends.

[0058] In this case, the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage at the end of the cell balancing mode can be defined as ΔV 最终 .

[0059] However, even though the cell balancing mode ends according to the satisfaction of the above-described cell balancing mode end condition, a cell voltage drop caused by a micro short circuit may continue to occur. To detect such a cell voltage drop, it can be determined whether the voltage of the cell with the minimum voltage continues to decrease by detecting whether the cell voltage deviation after completion of cell balancing is not less than a threshold.

[0060] In this case, it is possible to determine whether the voltage of the cell with the minimum voltage continues to decrease by determining whether the value obtained by multiplying the cell voltage deviation at the end of cell balancing by k (k is a constant) is not less than the initial cell voltage deviation (i.e., ΔV 初始 ).

[0061] That is to say, it is possible to determine whether the voltage of the cell with the minimum voltage continues to decrease based on whether the cell voltage deviation at the end of cell balancing satisfies the condition of the following Expression 1.

[0062] [Expression 1]

[0063] ΔV 初始 ≤k×ΔV 最终

[0064] In Expression 1, ΔV 初始 represents the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage at the start of the cell balancing mode, ΔV 最终 represents the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage at the end of the cell balancing mode, k represents a constant used to determine an abnormal voltage drop, and it can vary according to the battery type (e.g., NCM, LFP, and solid-state batteries).

[0065] In this case, "k×ΔV 最终 " in Expression 1 can be replaced by the target cell voltage deviation value.

[0066] Even for cells that have not yet experienced serious problems, it is possible to pre-diagnose the occurrence of internal micro-shorts, etc. based on whether the condition of Expression 1 is satisfied. Of course, even if abnormal symptoms indicating an internal cell short circuit process are detected in advance, it is difficult to prevent the occurrence of events such as fires.

[0067] On the other hand, it is possible to store the identifier (ID) of the cell with the minimum voltage after completing cell balancing.

[0068] In addition, when the voltage deviation between the cell with the maximum voltage and the cell with the minimum voltage among the multiple cells forming the battery module becomes not less than a predetermined threshold for starting the cell balancing mode again, the battery can enter or start the cell balancing mode again.

[0069] In this case, similar to the above case, it is possible to store the identifier (ID) of the cell with the minimum voltage after completing cell balancing.

[0070] In this case, it is possible to determine whether the identifier of the cell with the minimum voltage is the same as the previously stored identifier of the cell with the minimum voltage by comparison after ending the cell balancing mode.

[0071] In this case, when the identifier of the battery cell with the minimum voltage stored currently is the same as the identifier of the battery cell with the minimum voltage stored previously, a voltage drop alarm is generated, and the vehicle control unit (VCU) is configured to control the vehicle to limit the battery performance.

[0072] In this case, the voltage drop alarm is generated only when the battery temperature at the end of the battery cell balancing mode is not lower than the threshold temperature and the state of charge (SOC) value of the battery is not less than the threshold ratio.

[0073] For example, the voltage drop alarm is generated only when the battery temperature is 25 °C or higher and the SOC value of the battery is 30%.

[0074] Figure 2 is a block diagram schematically showing a battery abnormality diagnosis device according to an exemplary embodiment of the present invention.

[0075] Reference Figure 2 , the battery abnormality diagnosis device according to this exemplary embodiment includes: a battery 210, a battery cell balancing unit 230, a battery management unit 250, a sensor unit 270, and a vehicle control unit 290.

[0076] The battery 210 stores electric energy for driving the vehicle and includes a plurality of battery cells.

[0077] The battery management unit 230 is configured to: in the ignition mode of the vehicle, when the deviation between the average voltage of the plurality of battery cells and the voltage of the battery cell with the minimum voltage among the plurality of battery cells is not less than a predetermined threshold for starting the battery cell balancing mode, control the battery 210 to enter or start the battery cell balancing mode to reduce the voltage deviation between the plurality of battery cells forming the battery 210.

[0078] In this case, the deviation between the average voltage of the plurality of battery cells at the start of the battery cell balancing mode and the voltage of the battery cell with the minimum voltage can be defined as ΔV 初始 .

[0079] The battery management unit 230 may store the deviation (i.e., ΔV 初始 ) between the average voltage of the plurality of battery cells at the start of the battery cell balancing mode and the voltage of the battery cell with the minimum voltage, and the SOC value of the battery 210 in a storage device such as a memory.

[0080] In this case, the battery management unit 230 may be set to store the corresponding voltage deviation ΔV only when the temperature of the battery cell with the minimum voltage exceeds the threshold temperature and the SOC value of the battery 210 is not less than the threshold ratio. 初始and the SOC value of the battery 210.

[0081] For example, the battery management unit 230 can be set to store the corresponding voltage deviation ΔV only when the temperature of the battery cell with the minimum voltage exceeds 0 °C and the SOC value of the battery 210 is not less than 50%. 初始 and the SOC value of the battery 210.

[0082] In addition, when the battery cell balancing is completed, the battery management unit 230 ends the battery cell balancing mode.

[0083] In this case, when the threshold time has elapsed after the start of the battery cell balancing mode, the battery management unit 230 can end the battery cell balancing mode.

[0084] When the deviation between the SOCs of the battery cells forming the battery 210 is within a threshold range (e.g., 0.5% or less), the battery management unit 230 can be configured to determine that the battery cell balancing has been completed and, accordingly, end the battery cell balancing mode.

[0085] In addition, when the deviation between the average voltage of the battery cells forming the battery 210 and the voltage of the battery cell with the minimum voltage remains within the threshold range for a threshold period or longer than the threshold period, the battery management unit 230 can end the battery cell balancing mode.

[0086] For example, when the deviation between the average voltage of the battery cells forming the battery 210 and the voltage of the battery cell with the minimum voltage is 5 mV or less and this state persists for 10 seconds or longer than 10 seconds, the battery management unit 230 can end the battery cell balancing mode.

[0087] In this case, the deviation between the average voltage of the battery cells forming the battery 210 and the voltage of the battery cell with the minimum voltage at the end of the battery cell balancing mode can be defined as ΔV 最终 , as Figure 3 shown.

[0088] In this case, after the battery monitoring during the vehicle entering the ignition-off mode and then parking has been maintained for a threshold period or longer than the threshold period, at the first wake-up time of the real-time clock (RTC), the battery management unit 230 can store the corresponding ΔV 最终 and the SOC value of the battery 210 in a storage device such as a memory.

[0089] For example, the threshold time for continuous battery monitoring during parking can be 2 hours.

[0090] In this case, the battery management unit 230 stores the corresponding ΔV only when the temperature of the battery cell with the minimum voltage exceeds the threshold temperature and the SOC value of the battery 210 is at the threshold ratio or greater than the threshold ratio. 最终 and the SOC value of the battery 210.

[0091] For example, the battery management unit 230 may store the corresponding ΔV and the SOC value of the battery 210 only when the temperature of the battery cell with the minimum voltage exceeds 0 °C and the SOC value of the battery 210 is 50% or greater. 最终 and the SOC value of the battery 210.

[0092] When ΔV 初始 and ΔV 最终 both have been stored in a storage device such as a memory, the battery management unit 230 may increment the battery abnormality diagnosis count value based on whether the voltage deviation at the end of the battery cell balancing mode satisfies the condition of the following Expression 2.

[0093] [Expression 2]

[0094] ΔV 最终 ≥ΔV 初始 + threshold voltage drop

[0095] In Expression 2, ΔV 初始 represents the voltage deviation between the average voltage of the battery cells at the start of the battery cell balancing mode and the voltage of the battery cell with the minimum voltage, and ΔV 最终 represents the voltage deviation between the average voltage of the battery cells at the end of the battery cell balancing mode and the voltage of the battery cell with the minimum voltage. The threshold voltage drop represents the threshold voltage drop value for battery abnormality diagnosis counting.

[0096] In this case, when the condition of Expression 2 is initially satisfied, the battery abnormality diagnosis count value may change from 0 to 1.

[0097] On the other hand, when the voltage deviation at the end of the battery cell balancing mode satisfies the condition of Expression 2, the battery management unit 230 stores the identifier (ID) or identification number of the battery cell with the minimum voltage.

[0098] On the other hand, the battery management unit 230 is configured such that when the battery 210 ends the battery cell balancing mode after starting the battery cell balancing mode multiple times, and the condition of Expression 2 is satisfied at the end of the battery cell balancing mode, accordingly, the diagnosis count value increments to the threshold number of repetitions (i.e., N), and the identifier (ID) or identification number of the battery cell with the minimum voltage is the same each time, it is determined that an abnormality has occurred in the battery 210. In this case, the battery management unit 230 sends a warning message to the driver and sends information about the abnormality of the battery 210 to the vehicle controller 290.

[0099] In this case, a warning message can be sent through the vehicle's display screen or the vehicle's speaker.

[0100] As described above, the reason for comparing the average voltage of multiple battery cells with the voltage of the battery cell with the minimum voltage, rather than comparing the voltage of the battery cell with the maximum voltage with the voltage of the battery cell with the minimum voltage, is to prevent misdiagnosis caused by the deviation between the voltage of the battery cell with the maximum voltage and the voltage of the battery cell with the minimum voltage being too large under different SOC conditions.

[0101] In addition, ΔV is stored only when the SOC value of the battery 210 is not less than a threshold ratio. 初始 and ΔV 最终 The reason is to prevent misdiagnosis when the SOC difference between battery cells is large.

[0102] In addition, when the difference between the SOC value of the battery 210 at the start of the battery cell balancing mode and the SOC value of the battery 210 at the end of the battery cell balancing mode is 30% or more, and when the difference between the SOC value of the battery 210 when the vehicle enters the off mode after the battery cell balancing mode of the battery 210 ends and the SOC value of the battery 210 when the battery 210 enters the battery cell balancing mode is less than 30%, the battery management unit 230 monitors again the voltage deviation between the battery cells forming the battery module of the battery 210.

[0103] When the battery 210 enters the battery cell balancing mode through the battery management unit 230, the battery cell balancing unit 250 slightly consumes the current of the battery cells whose voltage is higher than the voltage of the battery cell with the minimum voltage, thereby reducing the voltage deviation between the battery cells.

[0104] The sensor unit 270 measures the voltage or temperature of the battery 210.

[0105] In this case, although not shown, the sensor unit 270 may include at least one voltage sensor and / or at least one temperature sensor.

[0106] The sensor unit 270 can measure the voltage change amount of all battery cells forming the battery 210.

[0107] The vehicle control unit 290 is configured to control the vehicle based on the output of the battery 210.

[0108] In this case, the vehicle control unit 290 receives information about an abnormality occurring in the battery 210 from the battery management unit 230 and is configured to control the vehicle based on the received information.

[0109] For example, when receiving information about an abnormality occurring in the battery 210 from the battery management unit 230, the vehicle control unit 290 may gradually reduce the speed of the vehicle or may be configured to control the vehicle to escape to a safe area.

[0110] Figure 4 is a flowchart showing a method for voltage deviation and SoC between battery cells at the start of a battery cell balancing mode according to an exemplary embodiment of the present invention.

[0111] can be performed by Figure 2 the battery management unit 230 of the battery abnormality diagnosis device 200 for the voltage deviation and SoC between battery cells at the start of a battery cell balancing mode according to an exemplary embodiment of the present invention.

[0112] In an exemplary embodiment of the present invention, each of the battery cell balancing unit 230, the battery management unit 250, and the vehicle control unit 290 may be implemented by a processor in the form of hardware or software or in a combination of hardware and software. Alternatively, the battery cell balancing unit 230, the battery management unit 250, and the vehicle control unit 290 may be implemented by a processor, and the processor may be implemented as a single processor in the form of hardware or software or in a combination of hardware and software.

[0113] Refer to Figure 4 , the battery management unit 230 is configured to determine whether the vehicle is in an ignition state (S410). When the vehicle is in an ignition state, the battery management unit 230 is configured to determine whether the difference between the average voltage of a plurality of battery cells forming a battery module of the vehicle and the voltage of the battery cell having the minimum voltage among the plurality of battery cells is not less than a first threshold (S420).

[0114] Based on the determination result of step S420, when the difference between the average voltage of the plurality of battery cells and the voltage of the battery cell having the minimum voltage is not less than the first threshold, the battery management unit 230 starts the battery cell balancing mode (S430) and starts the timing of the timer (S440).

[0115] On the other hand, based on the determination result of step S420, when the difference between the average voltage of the plurality of battery cells and the voltage of the battery cell having the minimum voltage is less than the first threshold, the battery management unit 230 executes step S410 of determining whether the vehicle is in an ignition state again.

[0116] In addition, the battery management unit 230 is configured to determine whether the temperature of the battery cell with the minimum voltage is higher than a first threshold temperature (S450). When the temperature of the battery cell with the minimum voltage is higher than the first threshold temperature, the battery management unit 230 is configured to determine whether the state of charge (SOC) value of the battery 210 is greater than a first threshold ratio (S460).

[0117] Based on the determination result of step S460, when the SOC value of the battery 210 is greater than the first threshold ratio, the battery management unit 230 stores the cell balance start voltage deviation corresponding to the difference between the average voltage of the plurality of battery cells at the start of the cell balance mode and the voltage of the battery cell with the minimum voltage, and the SOC value of the battery 210 (S470).

[0118] Steps S450 and S460 in Figure 4 may be executed sequentially, but it is not necessary to execute them sequentially, and the order of the steps may be changed to step S460 and step S450.

[0119] In this case, the cell balance start voltage deviation and the SOC value of the battery 210 may be stored in a storage device such as a memory that is connected to the battery management unit 230 or provided inside the battery management unit 230.

[0120] On the other hand, based on the determination result of step S450, when the temperature of the battery cell with the minimum voltage is not higher than the first threshold temperature, or based on the determination result of step S460, when the SOC value of the battery 210 is not greater than the first threshold ratio, the battery management unit 230 ends the control process without storing the cell balance start voltage deviation and the SOC value of the battery 210.

[0121] Figure 5A and Figure 5B are flowcharts showing a method of storing the voltage deviation between battery cells and the SoC at the end of the cell balance mode according to an exemplary embodiment of the present invention.

[0122] The method of storing the voltage deviation between battery cells and the SoC at the end of the cell balance mode according to an exemplary embodiment of the present invention may be performed by the battery management unit 230 of the battery abnormality diagnosis device 200 through Figure 2 .

[0123] Referring to Figure 5A and Figure 5B , the battery management unit 230 is configured to perform cell balance by controlling the cell balance unit 250 (S510).

[0124] In this case, the battery management unit 230 can perform cell balancing by controlling multiple cells forming the battery module to consume a micro current starting from the cells with voltages higher than the voltage of the cell with the minimum voltage.

[0125] In addition, the battery management unit 230 is configured to determine whether the timing of a timer set when starting the cell balancing mode has ended (S515). When the timing of the timer has ended, the battery management unit 230 ends the cell balancing mode (S530).

[0126] Based on the determination result of step S515, when the timing of the timer has not ended, the battery management unit 230 is configured to determine whether the difference between the average voltage of the multiple cells forming the battery 210 and the voltage of the cell with the minimum voltage among the multiple cells is not greater than a second threshold (S520).

[0127] Based on the determination result of step S520, when the difference between the average voltage of the multiple cells forming the battery 210 and the voltage of the cell with the minimum voltage is not greater than the second threshold, the battery management unit 230 is configured to determine whether the period during which the voltage difference is not greater than the second threshold has lasted for a first threshold time (S525). When the period during which the voltage difference is not greater than the second threshold has lasted for the first threshold time, the battery management unit 230 ends the cell balancing mode (S530).

[0128] In this case, the first threshold time can be set to a predetermined value according to user settings. For example, the first threshold time can be set to 10 seconds.

[0129] In addition, the battery management unit 230 is configured to determine whether the vehicle is in an off state (S535). When the vehicle is in an off state, the battery management unit 230 is configured to determine whether the continuous battery monitoring time during parking has elapsed for not less than a second threshold time (S540).

[0130] Based on the determination result of step S540, when the continuous battery monitoring time during parking has elapsed for not less than the second threshold time, the battery management unit 230 is configured to determine whether the real-time clock (RTC) is in a wake state (S545). When the RTC is in a wake state, the battery management unit 230 is configured to determine whether the temperature of the cell with the minimum voltage is greater than a second threshold temperature (S550). When the temperature of the cell with the minimum voltage is greater than the second threshold temperature, the battery management unit 230 is configured to determine whether the state of charge (SOC) value of the battery 210 is greater than a second threshold ratio (S555).

[0131] Based on the determination result of step S555, when the SOC value of the battery 210 is greater than the second threshold ratio, the battery management unit 230 stores the cell balance end voltage deviation corresponding to the voltage deviation between the average voltage of the cells at the end of the cell balance mode and the voltage of the cell with the minimum voltage, and the SOC value of the battery 210 (S560).

[0132] In this case, the cell balance end voltage deviation and the SOC value of the battery 210 can be stored in a storage device such as a memory, which is connected to the battery management unit 230 or provided inside the battery management unit 230.

[0133] On the other hand, based on the determination result of step S550, when the temperature of the cell with the minimum voltage is not higher than the second threshold temperature, or based on the determination result of step S555, when the SOC value of the battery 210 is not greater than the second threshold ratio, the battery management unit 230 ends the control process without storing the cell balance end voltage deviation and the SOC value of the battery 210.

[0134] Steps S550 and S555 in Figure 5B can be executed sequentially, but it is not necessary to execute them sequentially, and the order of the steps can be changed to step S555 and step S550.

[0135] Figure 6 is a flowchart showing a battery abnormality diagnosis method according to an exemplary embodiment of the present invention.

[0136] The battery abnormality diagnosis method according to an exemplary embodiment of the present invention can be executed by the battery management unit 230 of the Figure 2 battery abnormality diagnosis device.

[0137] Referring to Figure 6 , the battery management unit 230 sets the initial value of the counter for battery abnormality diagnosis to 0 (S605), and then is configured to determine whether the cell balance start voltage deviation and the cell balance end voltage deviation corresponding to the current count value have been stored in the memory of the battery management unit 230 or the memory connected to the battery management unit 230 (S610).

[0138] Based on the determination result of step S610, when there are the cell balance start voltage deviation and the cell balance end voltage deviation corresponding to the current count value, the battery management unit 230 is configured to determine whether the absolute value of the difference between the SOC value of the battery at the start of the cell balance mode and the current SOC value of the battery does not exceed the threshold range (S615).

[0139] In this case, the threshold range can be set to various values according to user settings, for example, it can be set to 30%.

[0140] When the absolute value of the difference between the SOC value of the battery when entering the cell balancing mode and the SOC value of the current battery does not exceed the threshold range, the battery management unit 230 is configured to determine whether the cell balancing end voltage deviation is not less than the value obtained by adding the cell balancing start voltage deviation and the threshold voltage drop (S620).

[0141] Based on the determination result of step S620, when the cell balancing end voltage deviation is not less than the value obtained by adding the cell balancing start voltage deviation and the threshold voltage drop, the battery management unit 230 increments the count value (S625), and then stores the count value and the identifier or identification number of the cell with the minimum voltage among the plurality of cells (S630).

[0142] In addition, the battery management unit 230 is configured to determine whether there is a repeated cell with the minimum voltage at different count values (which serves as a reference for starting and ending the cell balancing mode) (S635). When there is a repeated cell with the minimum voltage, the battery management unit 230 is configured to determine whether the current count value is not less than the threshold count value (S640).

[0143] Based on the determination result of step S640, when the current count value is not less than the threshold count value, the battery management unit 230 sends a warning message about battery abnormality to the driver and is configured to control the vehicle (S650).

[0144] In this case, the warning message can be sent through the vehicle's display screen or the vehicle's speaker.

[0145] In this case, the battery management unit 230 can be configured to control the vehicle by sending information about the occurrence of battery abnormality to the vehicle control unit 290.

[0146] For example, when receiving information about the occurrence of battery abnormality in the battery 210 from the battery management unit 230, the vehicle control unit 290 can gradually reduce the speed of the vehicle, or can be configured to control the vehicle to escape to a safe area.

[0147] According to the exemplary embodiments of the present invention described above, abnormal symptoms of the battery can be detected in advance.

[0148] In addition, a logic is provided, which is configured to diagnose a cell with abnormal symptoms by using a cell balancing technique for balancing the voltage deviation of a high-voltage battery, so as to perform high-voltage battery diagnosis.

[0149] In addition, accidents can be prevented by enhancing the high-voltage battery monitoring function, and the safety of the eco-friendly vehicle can be enhanced.

[0150] In addition, terms related to a control device such as "controller", "control device", "control unit", "control apparatus", "control module", or "server" refer to a hardware device including a memory and a processor (configured to execute one or more steps interpreted as an algorithmic structure). The memory stores algorithmic steps, and the processor executes the algorithmic steps to perform one or more processes of the method according to various exemplary embodiments of the present invention. The control device according to an exemplary embodiment of the present invention may be implemented by a non-volatile memory and a processor, the non-volatile memory being configured to store algorithms for controlling operations of various components of the vehicle or data of software instructions for executing the algorithms, and the processor being configured to perform the above operations using the data stored in the memory. The memory and the processor may be separate chips. Alternatively, the memory and the processor may be integrated in a single chip. The processor may be implemented as one or more processors. The processor may include various logic circuits and operation circuits, may be configured to process data according to a program provided by the memory, and may be configured to generate a control signal according to a processing result.

[0151] The control device may be at least one microprocessor operated by a predetermined program, and the predetermined program may include a series of instructions for performing the methods of the above various exemplary embodiments of the present invention.

[0152] The above invention may also be embodied as computer-readable code on a computer-readable recording medium. A computer-readable recording medium is any data storage device capable of storing data readable by a computer system later and storing and executing program instructions readable by a computer system later. Examples of computer-readable recording media include a hard disk drive (HDD), a solid state drive (SSD), a silicon disk drive (SDD), a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc., and an implementation using a carrier wave (e.g., transmission through the Internet). Examples of program instructions include machine language code such as code generated by a compiler and high-level language code that can be executed by a computer using an interpreter, etc.

[0153] In various exemplary embodiments of the present invention, each of the above operations may be performed by a control device, and the control device may be configured by a plurality of control devices or an integrated single control device.

[0154] In various exemplary embodiments of the present invention, the memory and the processor may be provided as one chip or as separate chips.

[0155] In various exemplary embodiments of the present invention, the scope of the present invention includes software or machine-executable instructions (e.g., operating systems, applications, firmware, programs, etc.) for enabling the operation of methods according to various embodiments to be executed on a device or computer, and non-volatile computer-readable media including such software or commands stored thereon and executable on the device or computer.

[0156] In various exemplary embodiments of the present invention, the control device may be implemented in the form of hardware or software, or may be implemented as a combination of hardware and software.

[0157] Furthermore, terms included in the specification (e.g., "unit", "module", etc.) refer to units for processing at least one function or operation, which may be implemented by hardware, software, or a combination thereof.

[0158] In an exemplary embodiment of the present invention, a vehicle may be referred to based on the concept including various means of transportation. In some cases, a vehicle may be interpreted based on the concept including not only various land-based means of transportation such as cars, motorcycles, trucks, and buses traveling on roads, but also various means of transportation such as airplanes, drones, ships, etc.

[0159] For the convenience of explanation and to accurately define the appended claims, the terms "above", "below", "inside", "outside", "upper", "lower", "upward", "downward", "front", "rear", "rear part", "inner side", "outer side", "inward", "outward", "internal", "external", "inner", "outer", "forward", and "backward" are used to describe the features of the exemplary embodiments with reference to the positions of these features shown in the drawings. It will be further understood that the term "connected" or its derivatives refer to direct connection and indirect connection.

[0160] 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 three cases, namely "A", "B", and "A and B".

[0161] In an exemplary embodiment 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". Furthermore, "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".

[0162] In this specification, unless the context clearly indicates otherwise, singular expressions include plural expressions.

[0163] In an exemplary embodiment of the present invention, it should be understood that terms such as "including" 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.

[0164] According to an exemplary embodiment of the present invention, components may be combined with each other to be implemented as one, or some components may be omitted.

[0165] Hereinafter, the fact that parts of the hardware are operatively coupled may include that a direct and / or indirect connection between the parts of the hardware is established by wired and / or wireless means.

[0166] For purposes of illustration and description, the foregoing description of specific exemplary embodiments of the present invention has been presented. The foregoing description is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously, many modifications and variations are possible in light of the above disclosure. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application so that others skilled in the art may implement and utilize the various exemplary embodiments of the invention and its various alternative and modified embodiments. The scope of the invention is intended to be defined by the appended claims and their equivalents.

Claims

1. A method for diagnosing a battery anomaly of a vehicle, the method comprising: Incrementing a count value by a processor based on a battery cell balance start voltage deviation and a battery cell balance end voltage deviation, and storing the count value and an identifier or identification number of a battery cell having the minimum voltage among a plurality of battery cells forming a battery module of the vehicle, the battery cell balance start voltage deviation being a voltage deviation of the plurality of battery cells at the start of a battery cell balance mode for adjusting the voltage deviation of the plurality of battery cells, and the battery cell balance end voltage deviation being a voltage deviation of the plurality of battery cells at the end of the battery cell balance mode; Detecting a battery cell anomaly by the processor based on the count value and the identifier or identification number of the battery cell having the minimum voltage.

2. The method according to claim 1, wherein Detecting a battery cell anomaly includes: detecting a battery cell anomaly based on whether there is a repeated identifier or identification number of a battery cell having the minimum voltage at different count values and whether the current count value is not less than a threshold count value.

3. The method according to claim 1, further comprising: Starting a battery cell balance mode by the processor, and storing the battery cell balance start voltage deviation by the processor; Ending the battery cell balance mode by the processor based on the voltage deviation of the plurality of battery cells or the elapsed time, and storing the battery cell balance end voltage deviation.

4. The method according to claim 1, wherein, Storing the count value and the identifier or identification number of the battery cell having the minimum voltage among the plurality of battery cells includes: Incrementing the count value in response to the battery cell balance end voltage deviation being not less than a value obtained by adding the battery cell balance start voltage deviation and a threshold voltage drop; Storing the count value and the identifier or identification number of the battery cell having the minimum voltage among the plurality of battery cells.

5. The method according to claim 1, wherein The count value is initially set to "0" and incremented by "1".

6. The method according to claim 3, wherein, The voltage deviation of the plurality of battery cells is a difference between an average voltage of the plurality of battery cells and a voltage of the battery cell having the minimum voltage among the plurality of battery cells.

7. The method according to claim 6, wherein During the process of starting the battery cell balance mode and storing the battery cell balance start voltage deviation, in response to a difference between an average voltage of the plurality of battery cells and a voltage of the battery cell having the minimum voltage among the plurality of battery cells being not less than a first threshold, the battery cell balance mode starts.

8. The method according to claim 6, wherein, During the process of ending the battery cell balance mode and storing the battery cell balance end voltage deviation, in response to a state where a difference between an average voltage of the plurality of battery cells and a voltage of the battery cell having the minimum voltage among the plurality of battery cells is not greater than a second threshold being maintained for a first threshold period of time, the battery cell balance mode ends.

9. The method according to claim 1, wherein During the process of ending the battery cell balance mode and storing the battery cell balance end voltage deviation, in response to a predetermined period of time having elapsed since the start of the battery cell balance mode, the battery cell balance mode ends.

10. The method according to claim 1, wherein During the process of starting the battery cell balance mode and storing the battery cell balance start voltage deviation, in response to, after the start of the battery cell balance mode, the temperature of the battery cell having the minimum voltage among the plurality of battery cells being higher than a first threshold temperature and the state of charge value of the battery being not less than a first threshold ratio, storing the battery cell balance start voltage deviation.

11. The method according to claim 1, wherein, During the process of ending the cell balancing mode and storing the cell balancing end voltage deviation, in response to, after the cell balancing mode ends, the temperature of the cell with the minimum voltage among the multiple cells being higher than the second threshold temperature and the state-of-charge value of the battery being not less than the second threshold ratio, store the cell balancing end voltage deviation.

12. The method according to claim 1, further comprising: In response to the identifier or identification number of the cell with the minimum voltage being repeated at different count values and the current count value being not less than the threshold count value, send a warning message to the driver and control the vehicle through the processor.

13. The method according to claim 1, further comprising: When it is inferred that a cell anomaly has occurred, the processor is configured to reduce the speed of the vehicle.

14. A device for diagnosing a battery anomaly of a vehicle, comprising: A battery configured to store electrical energy for driving the vehicle, the battery including a plurality of cells; A sensor unit including a voltage sensor configured to detect the voltages of the plurality of cells; And A battery management unit operably connected to the sensor unit and configured to: increment a count value based on the cell balancing start voltage deviation and the cell balancing end voltage deviation, store the count value and the identifier or identification number of the cell with the minimum voltage among the plurality of cells, detect a cell anomaly based on the count value and the identifier or identification number of the cell with the minimum voltage, the cell balancing start voltage deviation being the voltage deviation of the plurality of cells at the start of the cell balancing mode for adjusting the voltage deviation of the plurality of cells, and the cell balancing end voltage deviation being the voltage deviation of the plurality of cells at the end of the cell balancing mode.

15. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, The battery management unit is configured to: detect a cell anomaly based on whether the identifier or identification number of the cell with the minimum voltage is repeated at different count values and whether the current count value is not less than the threshold count value.

16. The device for diagnosing a battery anomaly of a vehicle according to claim 14, wherein The battery management unit starts the cell balancing mode and stores the cell balancing start voltage deviation; The battery management unit ends the cell balancing mode based on the voltage deviation of the plurality of cells or the elapsed time and stores the cell balancing end voltage deviation.

17. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, The battery management unit increments the count value in response to the cell balancing end voltage deviation being not less than the value obtained by adding the cell balancing start voltage deviation and the threshold voltage drop, and stores the count value and the identifier or identification number of the cell with the minimum voltage among the plurality of cells.

18. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, The count value is initially set to "0" and increments by "1".

19. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, The voltage deviation of the plurality of cells is the difference between the average voltage of the plurality of cells and the voltage of the cell with the minimum voltage among the plurality of cells.

20. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 18, wherein, In response to the difference between the average voltage of the plurality of cells and the voltage of the cell with the minimum voltage among the plurality of cells being not less than the first threshold, the battery management unit starts the cell balancing mode.

21. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 18, wherein, In response to a state where the difference between the average voltage of a plurality of battery cells and the voltage of the battery cell with the minimum voltage among the plurality of battery cells is not greater than a second threshold for a first threshold time period, the battery management unit ends the battery cell balancing mode.

22. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, In response to a predetermined time period having elapsed since the start of the battery cell balancing mode, the battery management unit ends the battery cell balancing mode.

23. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, In response to, after the start of the battery cell balancing mode, the temperature of the battery cell with the minimum voltage among the plurality of battery cells being higher than a first threshold temperature and the state of charge value of the battery being not less than a first threshold ratio, the battery management unit stores the battery cell balancing start voltage deviation.

24. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, In response to, after the end of the battery cell balancing mode, the temperature of the battery cell with the minimum voltage among the plurality of battery cells being higher than a second threshold temperature and the state of charge value of the battery being not less than a second threshold ratio, the battery management unit stores the battery cell balancing end voltage deviation.

25. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, wherein, In response to the identifier or identification number of the battery cell with the minimum voltage being repeated at different count values and the current count value being not less than a threshold count value, the battery management unit sends a warning message to the driver and is configured to control the vehicle.

26. The apparatus for diagnosing a battery abnormality of a vehicle according to claim 14, further comprising: a vehicle control unit operatively connected to the battery management unit; wherein, in response to the battery management unit inferring that a battery cell abnormality has occurred, the vehicle control unit is configured to reduce the speed of the vehicle.

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