Battery diagnosis device and method for operating same

Abstract

A battery diagnosis device according to one embodiment disclosed in the present document comprises: an information acquisition unit that acquires a shunt voltage and a shunt current of a current detection resistor included in a battery pack; a storage unit that stores the voltage of the battery pack; and a control unit that stores a first voltage, which is a voltage of the battery pack at a first point in time corresponding to a rest state of the battery pack, and a second voltage, which is a voltage of the battery pack at a second point in time, which is a point in time after a first interval from the first point in time, and diagnoses a state of the current detection resistor on the basis of the shunt current and a difference between the first voltage and the second voltage.

Description

Battery diagnostic device and method of operation thereof

[0001] Cross-citation with related applications

[0002] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2024-0020603, filed February 13, 2024, the entire contents of which are incorporated herein by reference.

[0003] Technology field

[0004] Embodiments disclosed in this document relate to a battery diagnostic device and an operating method thereof.

[0005] Recently, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has rapidly increased, and the development of electric vehicles, energy storage batteries, robots, and satellites has been in full swing, research into high-performance batteries capable of repeated charging and discharging is actively being conducted.

[0006] Currently commercialized batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium batteries. Among these, lithium batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based batteries.

[0007] Battery packs are used in a variety of fields, often requiring large capacities, such as electric vehicles or smart grid systems. While increasing battery pack capacity can be achieved by increasing the capacity of the secondary batteries themselves, this approach has the disadvantage of not achieving significant capacity gains and physical limitations on the expansion of secondary batteries. Therefore, battery packs consisting of multiple battery modules connected in series and parallel are typically widely used.

[0008] To measure the current of such a battery pack, a current detection resistor (shunt resistor) can be used. To achieve this, a microscopic resistor is connected in series within the battery pack, the voltage flowing across the resistor is measured, and the current can be calculated based on the resistance and voltage values. However, if the resistance value of the current detection resistor fluctuates, the measured current of the battery pack also fluctuates, making it difficult to guarantee the accuracy of the current measurement.

[0009] One purpose of the embodiments disclosed in this document is to provide a battery diagnostic device capable of measuring the current of a battery pack and an operating method thereof.

[0010] One purpose of the embodiments disclosed in this document is to provide a battery diagnostic device and an operating method thereof capable of diagnosing a defect in a current detection resistor of a battery pack.

[0011] One purpose of the embodiments disclosed in this document is to provide a battery diagnostic device and an operating method thereof capable of diagnosing an increase or decrease in a current detection resistance of a battery pack.

[0012] The technical problems of the embodiments described in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0013] A battery diagnosis device according to an embodiment disclosed in this document includes an information acquisition unit that acquires a shunt voltage and a shunt current of a current detection resistor (Shunt resistor) included in a battery pack, a storage unit that stores the voltage of the battery pack, and a control unit that stores a first voltage, which is a voltage of the battery pack at a first time point corresponding to a rest state of the battery pack, and a second voltage, which is a voltage of the battery pack at a second time point that is a time point after a first interval from the first time point, and diagnoses a state of the current detection resistor based on a difference between the second voltage and the first voltage and the shunt current.

[0014] According to one embodiment, the control unit can diagnose that a decrease drift has occurred in the current detection resistance when the shunt current corresponding to the second time point is equal to or greater than a preset first charge / discharge rate and a difference between the second voltage and the first voltage is less than a first preset value.

[0015] According to one embodiment, the control unit may store a third voltage, which is a voltage of the battery pack at a third time point that is a second interval after the first time point, and verify a diagnosis result based on a difference between the third voltage and the first voltage.

[0016] According to one embodiment, the control unit may determine the first set value based on the temperature of the battery pack.

[0017] According to one embodiment, the first set value may be proportional to the temperature of the battery pack.

[0018] According to one embodiment, the control unit can diagnose that an increase drift has occurred in the current detection resistance when the shunt current corresponding to the second time point is less than a preset second charge / discharge rate and a difference between the second voltage and the first voltage is greater than or equal to a second preset value.

[0019] According to one embodiment, the control unit may store a third voltage, which is a voltage of the battery pack at a third point in time that is a second interval after the first point in time, and verify a diagnosis result based on a difference between the third voltage and the first voltage.

[0020] According to one embodiment, the control unit can diagnose the state of the current detection resistor when the idle time, which is the time during which the state of the battery pack is maintained in an idle state prior to the first time point, is equal to or greater than a preset time.

[0021] According to one embodiment, the control unit may initialize the status diagnosis of the current detection resistor when the idle time is less than the preset time.

[0022] According to an embodiment disclosed in this document, a battery diagnosis device includes an operation of measuring a shunt voltage of a current detection resistor included in a battery pack in parallel with the shunt resistor, and obtaining a shunt current based on the current detection resistor and the shunt voltage, an operation of determining whether or not the current detection resistor is diagnosed, an operation of storing a first voltage, which is a voltage of the battery pack at a first time point corresponding to a rest state of the battery pack, and a second voltage, which is a voltage of the battery pack at a second time point, which is a time point after a first interval from the first time point, and an operation of diagnosing a state of the current detection resistor based on a difference between the second voltage and the first voltage and the shunt current.

[0023] According to one embodiment, the diagnosing operation may include an operation of diagnosing that a reduction drift has occurred in the current detection resistor when the shunt current corresponding to the second time point is equal to or greater than a preset first charge / discharge rate and a difference between the second voltage and the first voltage is less than a first preset value.

[0024] According to one embodiment, the diagnosing operation may include an operation of verifying a diagnosis result based on a difference between the first voltage and a third voltage, which is a voltage of the battery pack at a third time point that is a second interval after the first time point.

[0025] According to one embodiment, the first set value may be determined based on the temperature of the battery pack.

[0026] According to one embodiment, the diagnosing operation may include an operation of diagnosing that an increase drift has occurred in the current detection resistance when the shunt current corresponding to the second time point is less than a preset second charge / discharge rate and a difference between the second voltage and the first voltage is greater than or equal to a second preset value.

[0027] According to one embodiment, the operation of determining whether or not the current detection resistor is diagnosed may include an operation of diagnosing the state of the current detection resistor if the idle time, which is the time during which the state of the battery pack is maintained in an idle state before the first time point, is equal to or greater than a preset time, and initializing the state diagnosis of the current detection resistor if the idle time is less than the preset time.

[0028] Specific details of other embodiments are included in the detailed description and drawings.

[0029] The battery diagnostic device and its operating method according to the embodiments disclosed in this document can measure the current of a battery pack.

[0030] The battery diagnostic device and its operating method according to the embodiments disclosed in this document can diagnose a defect in the current detection resistor of a battery pack.

[0031] The battery diagnostic device and its operating method according to the embodiments disclosed in this document can diagnose an increase or decrease failure of the current detection resistance of a battery pack.

[0032] The battery diagnostic device and its operating method according to the embodiments disclosed in this document can improve the accuracy of fault diagnosis of a current detection resistor of a battery pack.

[0033] The effects of the battery diagnostic device and the operating method thereof according to the disclosure of this document are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art according to the disclosure of this document.

[0034] FIG. 1 is a block diagram showing a battery pack according to one embodiment disclosed in this document.

[0035] FIG. 2 is a block diagram showing a battery diagnostic device according to one embodiment disclosed in this document.

[0036] FIG. 3 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0037] FIG. 4 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0038] FIG. 5 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0039] FIG. 6 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0040] FIG. 7 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0041] FIG. 8 is a flowchart showing an operation method of a battery diagnostic device according to an embodiment disclosed in this document.

[0042] Fig. 9 is a flowchart specifically showing an operation for diagnosing the state of the current detection resistor of Fig. 8.

[0043] FIG. 10 is a block diagram showing a computing system that executes an operating method of a battery diagnostic device according to an embodiment disclosed in this document.

[0044] In connection with the description of the drawings, the same or similar reference numerals may be used for identical or similar components.

[0045] Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. However, this is not intended to limit the present invention to specific embodiments, and it should be understood that the present invention encompasses various modifications, equivalents, and / or alternatives of the embodiments.

[0046] The embodiments and terminology used in this document are not intended to limit the technical features described in this document to a specific embodiment, but should be understood to encompass various modifications, equivalents, or alternatives of the embodiment. In connection with the description of the drawings, similar reference numerals may be used to refer to similar or related components. The singular form of a noun corresponding to an item may include one or more of the item, unless the relevant context clearly indicates otherwise.

[0047] In this document, the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" can each include any one of the items listed together in that phrase, or all possible combinations thereof. Terms such as "first", "second", "first", "second", "A", "B", "(a)", or "(b)" may be used merely to distinguish the corresponding component from other corresponding components, and do not limit the corresponding components in any other respect (e.g., importance or order) unless specifically stated otherwise.

[0048] In this document, when a component (e.g., a first component) is referred to as being “connected,” “coupled,” or “connected,” with or without the terms “functionally” or “communicatively,” or “coupled” or “connected,” it means that the component can be connected to the other component directly (e.g., wired or wirelessly), or indirectly (e.g., via a third component).

[0049] The methods according to various embodiments disclosed in this document may be provided as included in a computer program product. The computer program product may be traded as a commodity between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory, CD-ROM), or may be distributed online (e.g., downloaded or uploaded) through an application store or directly between two user devices. In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily generated in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

[0050] According to the embodiments disclosed in this document, each component (e.g., a module or a program) of the above-described components may include one or more entities, and some of the entities may be separated and placed in other components. According to the embodiments disclosed in this document, one or more components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (e.g., a module or a program) may be integrated into a single component. In this case, the integrated component may perform one or more functions of each of the plurality of components identically or similarly to those performed by the corresponding component among the plurality of components prior to the integration. According to the embodiments disclosed in this document, the operations performed by a module, program, or other component may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

[0051] FIG. 1 is a block diagram showing a battery pack according to one embodiment disclosed in this document.

[0052] Referring to FIG. 1, a battery control system including a battery pack (1) and an upper controller (2) included in an upper system according to one embodiment disclosed in the present document is schematically illustrated.

[0053] As illustrated in FIG. 1, a battery pack (1) may include one or more battery cells (11), a switching unit (14) connected in series to a first terminal side and / or a second terminal side of the battery cell (11) to control the charge and discharge current flow of the battery cell (11), and a battery management system (20) that monitors voltage, current, temperature, etc. of the battery pack (1) to prevent overcharging and overdischarging, etc.

[0054] In this case, the battery pack (1) may be equipped with a plurality of battery cells (11), sensors (12), switching units (14), and battery management systems (20). For example, the first terminal may be the (+) terminal of the battery cell (11), and the second terminal may be the (-) terminal.

[0055] Here, the switching unit (14) is a device for controlling the current flow for charging or discharging of a plurality of battery cells (11), and for example, at least one relay, magnetic contactor, etc. may be used depending on the specifications of the battery pack (1).

[0056] The battery management system (20) is an interface that receives values ​​measured from the various parameters described above, and may include a plurality of terminals and a circuit that is connected to these terminals and processes the values ​​received. In addition, the battery management system (20) may control the ON / OFF of a switching unit (14), for example, a relay or a contactor, and may be connected to a battery cell (11) to monitor the status of each battery cell (11).

[0057] The upper controller (2) can transmit a control signal for the battery cell (11) to the battery management system (20). Accordingly, the battery management system (20) can be controlled in operation based on the signal received from the upper controller (2).

[0058] According to an embodiment, the battery management system (20) may include the battery diagnosis device (100) of FIG. 2. According to another embodiment, the battery management system (20) may be a different system from the battery diagnosis device (100) of FIG. 2. That is, the battery diagnosis device (100) of FIG. 2 may be included in the battery pack (1) or may be configured as another device external to the battery pack (1). For convenience of explanation, the following description assumes that the battery diagnosis device (100) is configured as another device external to the battery pack (1), but is not limited thereto. For example, the operation of the battery diagnosis device (100) described below may be performed by a BMS (Battery Management System) in a vehicle, as well as by various devices such as a server, a cloud, a charger, or a charger / discharger.

[0059] FIG. 2 is a block diagram showing a battery diagnostic device according to one embodiment disclosed in this document.

[0060] Referring to FIG. 2, the battery diagnostic device (100) may include an information acquisition unit (110), a storage unit (120), and a control unit (130). The battery diagnostic device (100) may diagnose the state of a current detection resistor using the information acquisition unit (110), the storage unit (120), and the control unit (130).

[0061] The information acquisition unit (110) can acquire information related to the battery pack (1). According to an embodiment, the information acquisition unit (110) can acquire information related to the battery pack (1) and the current detection resistor (shunt resistor) included in the battery pack (1). The information acquisition unit (110) can acquire the voltage of the battery pack (1) and the shunt voltage, which is the voltage applied to the current detection resistor. For example, the information acquisition unit (110) can acquire the shunt voltage by directly measuring the voltage difference between both terminals of the current detection resistor, but is not limited thereto.

[0062] According to an embodiment, the information acquisition unit (110) can acquire the shunt current, which is the current flowing into and out of the current detection resistor. For example, the information acquisition unit (110) can acquire the shunt current by calculating the shunt current based on the resistance of the stored shunt voltage and the acquired shunt voltage, but is not limited thereto.

[0063] According to an embodiment, the information acquisition unit (110) can continuously measure the shunt voltage and shunt current. For example, the information acquisition unit (110) can measure the shunt voltage and shunt current according to a preset cycle, and transmit the shunt voltage and shunt current measured according to the preset cycle to the control unit (130).

[0064] The storage unit (120) can store information related to the battery pack (1). According to an embodiment, the storage unit (120) can store the voltage of the battery pack (1). For example, the storage unit (120) can store the shunt voltage of the current detection resistor included in the battery pack (1). That is, the storage unit (120) can store the shunt voltage at multiple points in time based on the control of the control unit (130).

[0065] The control unit (130) can determine the resting state of the battery pack (1). According to an embodiment, the control unit (130) can determine the resting state of the battery pack (1) based on the shunt current. For example, the control unit (130) can determine the resting state of the battery pack (1) by comparing the shunt current with a set value set for determining the resting state. That is, the control unit (130) can determine the state of the battery pack (1) as the resting state when the magnitude of the shunt current is smaller than the set value. In addition, the control unit (130) can determine the state of the battery pack (1) as the active state when the magnitude of the shunt current is greater than the set value. Here, the set value may be 0.1 [A], but is not limited thereto.

[0066] According to an embodiment, the control unit (130) can measure the maintenance time of the idle state of the battery pack (1). For example, the control unit (130) can measure the maintenance time of the idle state using a first timer. Specifically, when the control unit (130) determines that the state of the battery pack (1) is an idle state, the control unit (130) can start the first timer. The first timer can measure the time based on the control of the control unit (130). Thereafter, when the control unit (130) determines that the state of the battery pack (1) is an active state, the control unit (130) can stop the operation of the first timer. Accordingly, the first timer can be stopped. The control unit (130) can measure the maintenance time of the idle state of the battery pack (1) based on the time from the start time of the first timer to the stop time.

[0067] According to an embodiment, the control unit (130) may determine whether to diagnose the status of the current detection resistor. The control unit (130) may determine whether to diagnose the status of the current detection resistor based on the duration of the idle state. For example, the control unit (130) may diagnose the status of the current detection resistor if the duration of the idle state is longer than a set time. Additionally, the control unit (130) may not diagnose the status of the current detection resistor if the duration of the idle state is shorter than the set time.

[0068] When the control unit (130) decides to diagnose the status of the current detection resistor, the control unit (130) may operate. That is, the control unit (130) may use the second timer to measure the passage of time during the diagnosis of the status of the current detection resistor.

[0069] The control unit (130) can store the voltage of the battery pack (1). According to an embodiment, the control unit (130) can store a first voltage, which is the voltage of the battery pack (1) at a first point in time corresponding to the resting state of the battery pack (1). That is, the first voltage may be the resting state voltage of the battery pack (1).

[0070] The control unit (130) can determine the activity state of the battery pack (1). According to an embodiment, the control unit (130) can determine the activity state of the battery pack (1) based on the shunt current. For example, the control unit (130) can determine the activity state of the battery pack (1) by comparing the shunt current with a set value set for determining the activity state. That is, the control unit (130) can determine the state of the battery pack (1) as an activity state when the magnitude of the shunt current is greater than the set value. In addition, the control unit (130) can determine the state of the battery pack (1) as an idle state when the magnitude of the shunt current is less than the set value. Here, the set value may be 0.1 [A], but is not limited thereto.

[0071] If the control unit (130) determines that the state of the battery pack (1) is in a dormant state, the control unit (130) can reset the second timer. In addition, if the control unit (130) determines that the state of the battery pack (1) is in an active state, the control unit (130) can continue diagnosing the current detection resistor.

[0072] Although the control unit (130) has been described above as utilizing the first timer and the second timer, it is not limited thereto. For example, the control unit (130) may also diagnose the current detection resistor based on a single timer.

[0073] According to an embodiment, the control unit (130) can determine the type of diagnosis. That is, the control unit (130) can determine whether to diagnose an increasing drift of the current detection resistor or a decreasing drift. Based on the shunt current, the control unit (130) can determine the diagnosis status as one of an increasing drift diagnosis, a decreasing drift diagnosis, and a diagnosis not possible.

[0074] For example, if the size of the shunt current is greater than or equal to a preset first charge / discharge rate, the control unit (130) may determine the diagnosis status as a diagnosis of reduced drift. That is, the control unit (130) may calculate the charge / discharge rate of the shunt current based on the size of the shunt current and the capacity of the battery pack (1), and if the calculated charge / discharge rate is greater than or equal to the first charge / discharge rate, the diagnosis status may be determined as a diagnosis of reduced drift, but is not limited thereto. As an example, the control unit (130) may determine the diagnosis status by comparing the size of the shunt current with a first reference value set in consideration of the capacity of the battery pack (1). Here, the first reference value may correspond to the first charge / discharge rate.

[0075] The control unit (130) may determine the diagnosis status as a diagnosis of increased drift when the magnitude of the shunt current is less than the preset second charge / discharge rate. That is, the control unit (130) may calculate the charge / discharge rate of the shunt current based on the magnitude of the shunt current and the capacity of the battery pack (1), and may determine the diagnosis status as a diagnosis of increased drift when the calculated charge / discharge rate is less than the second charge / discharge rate, but is not limited thereto. For example, the control unit (130) may determine the diagnosis status by comparing the magnitude of the shunt current with a second reference value set in consideration of the capacity of the battery pack (1). Here, the second reference value may correspond to the second charge / discharge rate.

[0076] Here, the first charge / discharge rate may be greater than the second charge / discharge rate. For example, the first charge / discharge rate may be 1 [C], and the second charge / discharge rate may be 0.5 [C]. Accordingly, a range between the first charge / discharge rate and the second charge / discharge rate may be determined. If the size of the shunt current is within the range, the control unit (130) may determine the diagnosis status as not diagnosable. In this case, the control unit (130) may initialize the status diagnosis of the current detection resistor.

[0077] When the control unit (130) performs an increase drift diagnosis of the current detection resistance, the control unit (130) can additionally store the voltage of the battery pack (1). That is, the control unit (130) can store a second voltage, which is the voltage of the battery pack (1) at a second time point, which is a time point after a first interval from the first time point. Here, the first interval may be 1 [s], but is not limited thereto.

[0078] The control unit (130) can diagnose a decrease drift of the current detection resistor based on the first voltage and the second voltage. According to an embodiment, the control unit (130) can diagnose an increase drift of the current detection resistor by comparing the difference between the second voltage and the first voltage with the first set value. For example, the control unit (130) can diagnose that a decrease drift has occurred in the current detection resistor when the difference between the first voltage and the second voltage is less than the first set value. In addition, the control unit (130) can diagnose the state of the current detection resistor as normal when the difference between the first voltage and the second voltage is equal to or greater than the first set value.

[0079] The control unit (130) can verify the diagnosis result. According to an embodiment, the control unit (130) can store the third voltage, which is the voltage of the battery pack (1) at a third time point, which is a time point after a second interval from the first time point. Here, the second interval may be greater than the first interval. That is, the third voltage may be a voltage acquired later in time than the first voltage and the second voltage. The control unit (130) can verify the diagnosis result based on the difference between the third voltage and the first voltage. For example, the control unit (130) can verify the diagnosis result as normal when the difference between the first voltage and the third voltage is less than a first set value. Additionally, the control unit (130) can verify the diagnosis result as abnormal when the difference between the first voltage and the third voltage is greater than or equal to the first set value.

[0080] According to an embodiment, if the control unit (130) determines that a decrease drift has occurred in the current detection resistor, the control unit (130) may open the current detection resistor. For example, the control unit (130) may open the current detection resistor by opening a switch connected in series to the current detection resistor, but is not limited thereto.

[0081] The control unit (130) can determine the first set value. According to an embodiment, the control unit (130) can determine the first set value based on the temperature of the battery pack (1). Since the current of the battery pack (1) increases as the temperature of the battery pack (1) increases and decreases as it decreases, the shunt current for diagnosing the current detection resistor can also increase as the temperature of the battery pack (1) increases and decrease as it decreases. Accordingly, the control unit (130) can determine the first set value, which is a comparison target of the shunt current, by considering the temperature of the battery pack (1). For example, the control unit (130) can increase the first set value when the temperature of the battery pack (1) increases. In addition, the control unit (130) can decrease the first set value when the temperature of the battery pack (1) decreases. That is, the first set value can be proportional to the temperature of the battery pack (1).

[0082] Meanwhile, when the control unit (130) performs a reduction drift diagnosis of the current detection resistance, the control unit (130) can additionally store the voltage of the battery pack (1). That is, the control unit (130) can store the second voltage, which is the voltage of the battery pack (1) at a second time point, which is a time point after a first interval from the first time point. Here, the first interval may be 1 [s], but is not limited thereto.

[0083] The control unit (130) can diagnose the increase drift of the current detection resistance based on the first voltage and the second voltage. According to an embodiment, the control unit (130) can diagnose the increase drift of the current detection resistance by comparing the difference between the second voltage and the first voltage with a second set value. For example, the control unit (130) can diagnose that an increase drift has occurred in the current detection resistance when the difference between the first voltage and the second voltage is greater than or equal to the second set value. In addition, the control unit (130) can diagnose the state of the current detection resistance as normal when the difference between the first voltage and the second voltage is less than the second set value.

[0084] The control unit (130) can verify the diagnosis result. According to an embodiment, the control unit (130) can store the third voltage, which is the voltage of the battery pack (1) at a third time point, which is a time point after a second interval from the first time point. Here, the second interval may be greater than the first interval. That is, the third voltage may be a voltage acquired later in time than the first voltage and the second voltage. The control unit (130) can verify the diagnosis result based on the difference between the third voltage and the first voltage. For example, the control unit (130) can verify the diagnosis result as normal when the difference between the first voltage and the third voltage is greater than or equal to a second set value. Additionally, the control unit (130) can verify the diagnosis result as abnormal when the difference between the first voltage and the third voltage is less than the second set value.

[0085] According to an embodiment, if the control unit (130) determines that an increase drift has occurred in the current detection resistor, the control unit (130) may open the current detection resistor. For example, the control unit (130) may open the current detection resistor by opening a switch connected in series to the current detection resistor, but is not limited thereto.

[0086] The control unit (130) can determine the second set value. According to an embodiment, the control unit (130) can determine the second set value based on the temperature of the battery pack (1). Since the current of the battery pack (1) increases as the temperature of the battery pack (1) increases and decreases as it decreases, the shunt current for diagnosing the current detection resistor can also increase as the temperature of the battery pack (1) increases and decrease as it decreases. Accordingly, the control unit (130) can determine the second set value, which is a comparison target of the shunt current, by considering the temperature of the battery pack (1). For example, the control unit (130) can increase the second set value when the temperature of the battery pack (1) increases. In addition, the control unit (130) can decrease the second set value when the temperature of the battery pack (1) decreases. That is, the second set value can be proportional to the temperature of the battery pack (1).

[0087] According to an embodiment, if the control unit (130) diagnoses the state of the current detection resistor as increasing drift or decreasing drift, the control unit (130) may provide the diagnostic results to the user. For example, the control unit (130) may provide the diagnostic results to the user terminal via a communication unit (not shown), and may also provide the diagnostic results to the user via a display provided in a vehicle or charger.

[0088] Hereinafter, with reference to FIGS. 3 to 7, a method for a battery diagnostic device (100) to diagnose a current detection resistance according to individual circumstances of a battery pack (1) will be described. In FIGS. 3 to 7, a first graph (GRAPH1) represents the operation of a first timer over time. A second graph (GRAPH2) represents the operation of a second timer over time. A third graph (GRAPH3) represents the magnitude of a shunt current over time. A fourth graph (GRAPH4) represents the difference between a first voltage and a second voltage over time. A fifth graph (GRAPH5) represents a diagnostic signal over time.

[0089] The battery diagnostic device (100) can measure the current of the battery pack (1) based on the resistance value of the current detection resistor and the shunt voltage. In addition, the battery diagnostic device (100) can diagnose a defect in the current detection resistor of the battery pack (1) based on the shunt voltage and shunt current.

[0090] The battery diagnostic device (100) can diagnose an increase or decrease in the current detection resistance of the battery pack (1) by comparing the voltage of the active state and the voltage of the resting state of the battery pack (1).

[0091] The battery diagnostic device (100) can improve the accuracy of diagnosing the current detection resistance of the battery pack (1) by diagnosing the current detection resistance only when the shunt current is maintained for a set period of time or longer. That is, the battery diagnostic device (100) can improve the accuracy of diagnosing the current detection resistance by preventing a situation in which the current detection resistance is diagnosed based on a temporarily increased or decreased current.

[0092] FIG. 3 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0093] Referring to FIG. 3, the control unit (130) can diagnose the state of the current detection resistor. The control unit (130) can determine the idle state of the battery pack (1). Referring to the third graph (GRAPH3), if the shunt current is less than a set value, the control unit (130) can determine the state of the battery pack (1) as an idle state. Referring to the first graph (GRAPH1), if the control unit (130) determines that the state of the battery pack (1) is an idle state, the control unit (130) can start a first timer. The control unit (130) can measure the duration of the idle state of the battery pack (1) using the first timer. If the duration of the idle state of the control unit (130) is greater than or equal to a set time, the control unit (130) can stop the first timer and start a second timer. Here, the set time may be 10 [s], but is not limited thereto.

[0094] Referring to the second graph (GRAPH2), the control unit (130) can start the second timer along with stopping the first timer. The control unit (130) can use the second timer to measure the passage of time during the status diagnosis of the current detection resistor. According to an embodiment, the control unit (130) can start the second timer for a set time, check the shunt current, and stop and reset the second timer. Here, the set time may be 1 [s], but is not limited thereto.

[0095] Referring to the third graph (GRAPH3), the control unit (130) can check the shunt current at the time of stopping the second timer. If the shunt current is greater than the first charge / discharge rate, the control unit (130) can diagnose the state of the current detection resistor by considering the shunt voltage. Here, the first charge / discharge rate may be 1 [C], but is not limited thereto.

[0096] Referring to the fourth graph (GRAPH4), the control unit (130) can diagnose the state of the current detection resistor based on the shunt voltage. According to an embodiment, the control unit (130) can compare the difference between the first voltage, which is the voltage of the battery pack (1) at a first point in time corresponding to the resting state of the battery pack (1), and the second voltage, which is the voltage of the battery pack (1) at a second point in time that is a first interval after the first point in time, with a first set value. If the difference between the first voltage and the second voltage is equal to or greater than the first set value, the control unit (130) can determine that the state of the current detection resistor is normal and initialize the diagnosis of the current detection resistor.

[0097] FIG. 4 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0098] Referring to FIG. 4, the control unit (130) can diagnose the state of the current detection resistor. The control unit (130) can determine the idle state of the battery pack (1). Referring to the third graph (GRAPH3), if the shunt current is less than a set value, the control unit (130) can determine the state of the battery pack (1) as an idle state. Referring to the first graph (GRAPH1), if the control unit (130) determines that the state of the battery pack (1) is an idle state, the control unit (130) can start a first timer. The control unit (130) can measure the duration of the idle state of the battery pack (1) using the first timer. If the duration of the idle state of the control unit (130) is greater than or equal to a set time, the control unit (130) can stop the first timer and start a second timer. Here, the set time may be 10 [s], but is not limited thereto.

[0099] Referring to the second graph (GRAPH2), the control unit (130) can start the second timer along with stopping the first timer. The control unit (130) can use the second timer to measure the passage of time during the status diagnosis of the current detection resistor. According to an embodiment, the control unit (130) can start the second timer for a set time, check the shunt current, and stop and reset the second timer. Here, the set time may be 1 [s], but is not limited thereto.

[0100] Referring to the third graph (GRAPH3), the control unit (130) can check the shunt current at the time of stopping the second timer. If the shunt current is greater than or equal to the second charge / discharge rate and less than the first charge / discharge rate, the control unit (130) can determine the diagnostic status of the current detection resistor as not diagnosable. In this case, the control unit (130) can initialize the status diagnosis of the current detection resistor. Here, the first charge / discharge rate may be 1 [C], and the second charge / discharge rate may be 0.5 [C], but is not limited thereto.

[0101] FIG. 5 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0102] Referring to FIG. 5, the control unit (130) can diagnose the state of the current detection resistor. The control unit (130) can determine the idle state of the battery pack (1). Referring to the third graph (GRAPH3), if the shunt current is less than a set value, the control unit (130) can determine the state of the battery pack (1) as an idle state. Referring to the first graph (GRAPH1), if the control unit (130) determines that the state of the battery pack (1) is an idle state, the control unit (130) can start a first timer. The control unit (130) can measure the duration of the idle state of the battery pack (1) using the first timer. If the duration of the idle state of the control unit (130) is greater than or equal to a set time, the control unit (130) can stop the first timer and start a second timer. Here, the set time may be 10 [s], but is not limited thereto.

[0103] Referring to the second graph (GRAPH2), the control unit (130) can start the second timer along with stopping the first timer. The control unit (130) can use the second timer to measure the passage of time during the status diagnosis of the current detection resistor. In this case, the control unit (130) can store the first voltage, which is the voltage of the battery pack (1) at the time of operation of the second timer. According to an embodiment, the control unit (130) can check the shunt current after operating the second timer for a set time, and stop and reset the second timer. Here, the set time may be 1 [s], but is not limited thereto.

[0104] Referring to the third graph (GRAPH3), the control unit (130) can check the shunt current at the time of stopping the second timer. If the shunt current does not flow at the time of stopping the second timer, the control unit (130) can initialize the diagnosis of the current detection resistor. That is, the control unit (130) can diagnose the current detection resistor based on the shunt current only when the shunt current is maintained for a set time or longer. Through this, the control unit (130) can prevent misdiagnosis of the current detection resistor due to a phenomenon in which the current temporarily increases or decreases, thereby improving the accuracy of the current detection resistor diagnosis.

[0105] FIG. 6 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0106] Referring to FIG. 6, the control unit (130) can diagnose the state of the current detection resistor. The control unit (130) can determine the idle state of the battery pack (1). Referring to the third graph (GRAPH3), if the shunt current is less than a set value, the control unit (130) can determine the state of the battery pack (1) as an idle state. Referring to the first graph (GRAPH1), if the control unit (130) determines that the state of the battery pack (1) is an idle state, the control unit (130) can start a first timer. The control unit (130) can measure the duration of the idle state of the battery pack (1) using the first timer. If the duration of the idle state of the control unit (130) is greater than or equal to a set time, the control unit (130) can stop the first timer and start a second timer. Here, the set time may be 10 [s], but is not limited thereto.

[0107] Referring to the second graph (GRAPH2), the control unit (130) can start the second timer along with stopping the first timer. The control unit (130) can use the second timer to measure the passage of time during the status diagnosis of the current detection resistor. According to an embodiment, the control unit (130) can start the second timer for a set time, check the shunt current, and stop and reset the second timer. Here, the set time may be 1 [s], but is not limited thereto.

[0108] Referring to the third graph (GRAPH3), the control unit (130) can check the shunt current at the time of stopping the second timer. If the shunt current is greater than the first charge / discharge rate, the control unit (130) can diagnose the state of the current detection resistor by considering the shunt voltage. Here, the first charge / discharge rate may be 1 [C], but is not limited thereto.

[0109] Referring to the fourth graph (GRAPH4), the control unit (130) can diagnose the state of the current detection resistor based on the shunt voltage. According to an embodiment, the control unit (130) can compare the difference between the first voltage, which is the voltage of the battery pack (1) at a first point in time corresponding to the rest state of the battery pack (1), and the second voltage, which is the voltage of the battery pack (1) at a second point in time, which is a point in time after a first interval from the first point in time, with a first set value. If the difference between the first voltage and the second voltage is less than the first set value, the control unit (130) can diagnose the state of the current detection resistor as a reduction drift. In this case, the control unit (130) can verify the diagnosis result. For example, the control unit (130) can store the third voltage, which is the point in time after the second interval from the first point in time, and compare the difference between the first voltage and the third voltage with the first set value. If the difference between the first voltage and the third voltage is less than the first set value, the control unit (130) can verify the diagnosis result as normal.

[0110] Referring to the fifth graph (GRAPH5), the control unit (130) can input a diagnostic signal. According to an embodiment, if the control unit (130) determines that the state of the current detection resistor is a reduction drift, the control unit (130) can input a diagnostic signal. If the diagnostic signal is confirmed, the control unit (130) can open the current detection resistor. For example, the control unit (130) can open the current detection resistor by opening a switch connected in series to the current detection resistor.

[0111] FIG. 7 is a schematic diagram showing a method for diagnosing a current measuring resistance of a battery diagnostic device according to an embodiment disclosed in this document.

[0112] Referring to FIG. 7, the control unit (130) can diagnose the state of the current detection resistor. The control unit (130) can determine the idle state of the battery pack (1). Referring to the third graph (GRAPH3), if the shunt current is less than a set value, the control unit (130) can determine the state of the battery pack (1) as an idle state. Referring to the first graph (GRAPH1), if the control unit (130) determines that the state of the battery pack (1) is an idle state, the control unit (130) can start a first timer. The control unit (130) can measure the duration of the idle state of the battery pack (1) using the first timer. If the duration of the idle state of the control unit (130) is greater than or equal to a set time, the control unit (130) can stop the first timer and start a second timer. Here, the set time may be 10 [s], but is not limited thereto.

[0113] Referring to the second graph (GRAPH2), the control unit (130) can start the second timer along with stopping the first timer. The control unit (130) can use the second timer to measure the passage of time during the status diagnosis of the current detection resistor. According to an embodiment, the control unit (130) can start the second timer for a set time, check the shunt current, and stop and reset the second timer. Here, the set time may be 1 [s], but is not limited thereto.

[0114] Referring to the third graph (GRAPH3), the control unit (130) can check the shunt current at the time of stopping the second timer. If the shunt current is lower than the second charge / discharge rate, the control unit (130) can diagnose the state of the current detection resistor by considering the shunt voltage. Here, the second charge / discharge rate may be 0.5 [C], but is not limited thereto.

[0115] Referring to the fourth graph (GRAPH4), the control unit (130) can diagnose the state of the current detection resistor based on the shunt voltage. According to an embodiment, the control unit (130) can compare the difference between the first voltage, which is the voltage of the battery pack (1) at a first point in time corresponding to the rest state of the battery pack (1), and the second voltage, which is the voltage of the battery pack (1) at a second point in time, which is a point in time after a first interval from the first point in time, with a second set value. If the difference between the first voltage and the second voltage is less than the second set value, the control unit (130) can diagnose the state of the current detection resistor as an increase drift. In this case, the control unit (130) can verify the diagnosis result. For example, the control unit (130) can store the third voltage, which is the point in time after the second interval from the first point in time, and compare the difference between the first voltage and the third voltage with the second set value. If the difference between the first voltage and the third voltage is less than the second set value, the control unit (130) can verify the diagnosis result as normal.

[0116] Referring to the fifth graph (GRAPH5), the control unit (130) can input a diagnostic signal. According to an embodiment, if the control unit (130) determines that the state of the current detection resistor is an increasing drift, the control unit (130) can input a diagnostic signal. If the diagnostic signal is confirmed, the control unit (130) can open the current detection resistor. For example, the control unit (130) can open the current detection resistor by opening a switch connected in series to the current detection resistor.

[0117] FIG. 8 is a flowchart showing an operation method of a battery diagnostic device according to an embodiment disclosed in this document.

[0118] The embodiment illustrated in FIG. 8 is only one embodiment, and the order of operations according to various embodiments of the present invention may differ from that illustrated in FIG. 8, and some of the steps illustrated in FIG. 8 may be omitted, the order between the steps may be changed, or the steps may be merged. In the following, the contents described in FIGS. 1 to 7 are omitted.

[0119] Referring to FIG. 8, the operating method of the battery diagnosis device (100) may include an operation (S100) of connecting in parallel to a current detection resistor (Shunt resistor) included in a battery pack (1), measuring a shunt voltage of the current detection resistor, and obtaining a shunt current based on the current detection resistor and the shunt voltage, an operation (S200) of determining whether diagnosis of the current detection resistor is possible, an operation (S300) of storing a first voltage, which is a voltage of the battery pack (1) at a first point in time corresponding to a resting state of the battery pack (1), and a second voltage, which is a voltage of the battery pack (1) at a second point in time, which is a point in time after a first interval from the first point in time, and an operation (S400) of diagnosing a state of the current detection resistor based on a difference between the second voltage and the first voltage and the shunt current.

[0120] Fig. 9 is a flowchart specifically showing an operation for diagnosing the state of the current detection resistor of Fig. 8.

[0121] Referring to FIG. 9, the operation for diagnosing the state of the current detection resistor may include an operation for determining whether the shunt current corresponding to the second time point is equal to or greater than a preset first charge / discharge rate (S410), an operation for determining whether the difference between the second voltage and the first voltage is less than a first preset value (S420), an operation for diagnosing whether a decrease drift has occurred in the current detection resistor (S430), an operation for determining whether the shunt current corresponding to the second time point is less than a preset second charge / discharge rate (S440), an operation for determining whether the difference between the second voltage and the first voltage is equal to or greater than the second preset value (S450), an operation for diagnosing whether an increase drift has occurred in the current detection resistor (S460), and an operation for initializing the diagnosis (S470).

[0122] In operation S410, if the battery diagnostic device (100) determines that the shunt current corresponding to the second time point is greater than or equal to the preset first charge / discharge rate, operation S420 may be performed. In addition, if the battery diagnostic device (100) determines that the shunt current corresponding to the second time point is less than the preset first charge / discharge rate, operation S470 may be performed.

[0123] In operation S420, if the battery diagnostic device (100) determines that the difference between the second voltage and the first voltage is less than the first set value, operation S430 may be performed. In addition, if the battery diagnostic device (100) determines that the difference between the second voltage and the first voltage is greater than or equal to the first set value, operation S470 may be performed.

[0124] In operation S440, if the battery diagnostic device (100) determines that the shunt current corresponding to the second time point is less than the preset second charge / discharge rate, operation S450 may be performed. In addition, if the battery diagnostic device (100) determines that the shunt current corresponding to the second time point is greater than or equal to the preset second charge / discharge rate, operation S470 may be performed.

[0125] In operation S450, if the battery diagnostic device (100) determines that the difference between the second voltage and the first voltage is greater than or equal to the second set value, operation S460 may be performed. In addition, if the battery diagnostic device (100) determines that the difference between the second voltage and the first voltage is greater than or equal to the second set value, operation S470 may be performed.

[0126] FIG. 10 is a block diagram showing a computing system that executes an operating method of a battery diagnostic device according to an embodiment disclosed in this document.

[0127] Referring to FIG. 10, a computing system (200) according to an embodiment disclosed in the present document may include an MCU (210), a memory (220), an input / output I / F (230), and a communication I / F (240).

[0128] The MCU (210) may be a processor that executes various programs stored in the memory (220) (e.g., an SOH calculation program, a cell balancing target determination program, etc.), processes various data including SOC, SOH, etc. of multiple battery cells through these programs, and performs the functions of the battery diagnosis device (100) described with reference to FIGS. 1 to 9 described above.

[0129] The memory (220) can store various programs related to calculating the SOH of a battery cell and determining whether to perform cell balancing. In addition, the memory (220) can store various data, such as SOC and SOH data for each battery cell.

[0130] Such memories (220) may be provided in multiple numbers as needed. The memories (220) may be volatile memories or non-volatile memories. As volatile memories (220), RAM, DRAM, SRAM, etc. may be used. As non-volatile memories (220), ROM, PROM, EAROM, EPROM, EEPROM, flash memories, etc. may be used. The examples of the memories (220) listed above are merely examples and are not limited to these examples.

[0131] The input / output I / F (230) can provide an interface that enables data transmission and reception between an input device (not shown) such as a keyboard, mouse, or touch panel, and an output device (not shown) such as a display and the MCU (210).

[0132] The communication I / F (240) is a component capable of transmitting and receiving various data with a server, and may be any device capable of supporting wired or wireless communication. For example, programs for calculating the SOH of a battery cell or determining a balancing target, as well as various data, can be transmitted and received from a separately provided external server via the communication I / F (240).

[0133] In this way, the operating method of the battery diagnostic device according to one embodiment disclosed in this document can be recorded in the memory (220) and executed by the MCU (210).

[0134] The above description is merely an example of the technical idea disclosed in this document, and those skilled in the art to which the embodiments disclosed in this document pertain may make various modifications and variations without departing from the essential characteristics of the embodiments disclosed in this document.

[0135] Accordingly, the embodiments disclosed in this document are intended to illustrate, rather than limit, the technical concepts disclosed in this document, and the scope of the technical concepts disclosed in this document is not limited by these embodiments. The scope of protection of the technical concepts disclosed in this document should be interpreted by the claims below, and all technical concepts within the equivalent scope should be interpreted as being included within the scope of the rights of this document.

[0136] [Explanation of symbols]

[0137] 100: Battery Diagnostic Device

[0138] 110: Information Acquisition Department

[0139] 120: Storage

[0140] 130: Control unit

Claims

1. An information acquisition unit that acquires the shunt voltage and shunt current of a current detection resistor (shunt resistor) included in a battery pack; A storage unit for storing the voltage of the battery pack; and Store a first voltage, which is the voltage of the battery pack at a first point in time corresponding to the resting state of the battery pack, and a second voltage, which is the voltage of the battery pack at a second point in time corresponding to a first interval from the first point in time, A battery diagnostic device including a control unit that diagnoses the state of the current detection resistor based on the difference between the second voltage and the first voltage and the shunt current.

2. In paragraph 1, The above control unit is such that the shunt current corresponding to the second time point is equal to or greater than the preset first charge / discharge rate, A battery diagnostic device that diagnoses that a reduction drift has occurred in the current detection resistor when the difference between the second voltage and the first voltage is less than the first set value.

3. In paragraph 2, The above control unit stores a third voltage, which is the voltage of the battery pack at a third point in time, which is a point in time after a second interval from the first point in time, A battery diagnostic device that verifies a diagnostic result based on the difference between the third voltage and the first voltage.

4. In paragraph 2, A battery diagnostic device wherein the control unit determines the first set value based on the temperature of the battery pack.

5. In paragraph 4, The above first set value is a battery diagnostic device proportional to the temperature of the battery pack.

6. In paragraph 1, The above control unit is configured such that the shunt current corresponding to the second time point is less than the preset second charge / discharge rate, A battery diagnostic device that diagnoses that an increase drift has occurred in the current detection resistor when the difference between the second voltage and the first voltage is greater than or equal to the second set value.

7. In paragraph 6, The above control unit stores a third voltage, which is the voltage of the battery pack at a third point in time, which is a point in time after a second interval from the first point in time, A battery diagnostic device that verifies a diagnostic result based on the difference between the third voltage and the first voltage.

8. In paragraph 1, The control unit is a battery diagnostic device that diagnoses the state of the current detection resistor when the idle time, which is the time during which the state of the battery pack is maintained in an idle state prior to the first point in time, is greater than a preset time.

9. In paragraph 8, The above control unit is a battery diagnostic device that initializes the status diagnosis of the current detection resistor when the above idle time is less than the preset time.

10. An operation of connecting in parallel to a current detection resistor (shunt resistor) included in a battery pack, measuring the shunt voltage of the current detection resistor, and obtaining a shunt current based on the current detection resistor and the shunt voltage; An operation for determining whether or not the above current detection resistor is diagnosed; An operation of storing a first voltage, which is the voltage of the battery pack at a first point in time corresponding to the resting state of the battery pack, and a second voltage, which is the voltage of the battery pack at a second point in time corresponding to a first interval from the first point in time; and An operating method of a battery diagnostic device, including an operation of diagnosing a state of the current detection resistor based on the difference between the second voltage and the first voltage and the shunt current.

11. In paragraph 10, The above diagnosing operation is such that the shunt current corresponding to the second time point is greater than or equal to the preset first charge / discharge rate, An operating method of a battery diagnostic device, including an operation for diagnosing that a reduction drift has occurred in the current detection resistor when the difference between the second voltage and the first voltage is less than a first set value.

12. In paragraph 11, A method of operating a battery diagnostic device, wherein the above diagnostic operation includes an operation of verifying a diagnostic result based on a difference between the first voltage and a third voltage, which is a voltage of the battery pack at a third point in time that is a point in time after a second interval from the first point in time.

13. In paragraph 11, The above first set value is a method of operating a battery diagnostic device determined based on the temperature of the battery pack.

14. In paragraph 10, The above diagnosing operation is performed when the shunt current corresponding to the second time point is less than the preset second charge / discharge rate, An operating method of a battery diagnostic device, including an operation for diagnosing that an increase drift has occurred in the current detection resistor when the difference between the second voltage and the first voltage is greater than or equal to a second set value.

15. In paragraph 10, The operation of determining whether or not the above current detection resistance is diagnosed is as follows: If the idle time, which is the time during which the state of the battery pack is maintained in an idle state prior to the first point in time, is greater than a preset time, the state of the current detection resistor is diagnosed, An operating method of a battery diagnostic device, comprising an operation of initializing a status diagnosis of the current detection resistor when the above-mentioned idle time is less than the above-mentioned preset time.

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