Battery diagnostic apparatus and method of operating same

Abstract

A battery diagnosis apparatus according to an embodiment disclosed in the present document includes: an acquisition unit that acquires a first voltage value of each of a plurality of battery cells; an identification unit that identifies a second voltage value of a different standby section among the first voltage values; a determination unit that determines a voltage slope indicating a degree of change over time of a second voltage value of each of the plurality of battery cells, and determines a second voltage value of each of the plurality of battery cells by using an average value of a plurality of voltage slopes corresponding one-to-one to each of the plurality of battery cells and a standard deviation, determining a standard score (Z-score) of a voltage slope for each of the plurality of battery cells; and a diagnosis unit that selects, among the plurality of battery cells, battery cells having a standard fraction outside a first reference range and a voltage slope outside a second reference range, and diagnoses at least some of the selected battery cells as abnormal battery cells.

Description

Technical Field

[0001] Cross - Reference to Related Applications

[0002] This application claims the priority and benefit of Korean Patent Application No. 10 - 2022 - 0151069, filed with the Korean Intellectual Property Office on November 11, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0004] Embodiments disclosed herein relate to a battery diagnostic device and an operating method thereof. Background Art

[0005] Recently, research and development of secondary batteries have been actively carried out. Herein, secondary batteries as rechargeable / dischargeable batteries may include all conventional nickel (Ni) / cadmium (Cd) batteries, Ni / metal hydride (MH) batteries, etc., as well as recent lithium - ion batteries. Among secondary batteries, lithium - ion batteries have a much higher energy density than conventional Ni / Cd batteries, Ni / MH batteries, etc. In addition, lithium - ion batteries can be made smaller and lighter in weight, such that lithium - ion batteries are used as power sources for mobile devices. Recently, the use range of lithium - ion batteries has been extended to power sources for electric vehicles, attracting attention as next - generation energy storage media.

[0006] In addition, secondary batteries can be used as battery packs including battery modules, in which multiple battery cells are connected in series and / or in parallel with each other. Secondary batteries can be used as battery racks including multiple battery modules and rack frames for receiving battery modules.

[0007] Battery cells, battery modules, battery packs, or battery racks can be used in various devices. For example, batteries can be used not only in mobile devices such as mobile phones, laptop computers, smartphones, smart tablets, etc., but also in fields such as electric - powered vehicles (EV, HEV, PHEV), large - capacity energy storage systems (ESS), etc.

[0008] These batteries can be managed and controlled by a battery management system (BMS) according to their states and operations. The battery management system can be included in a device together with the battery. The battery management system can also manage and control the battery in a state spaced apart from the device including the battery. Summary of the Invention

[0009] Technical Problem

[0010] When a short - circuit or another type of failure occurs inside the battery, the possibility of damaging a device including the battery (e.g., EV, ESS) may increase.

[0011] Therefore, a solution is needed to reduce the possibility of damaging a device including a battery by detecting an abnormal state of the battery.

[0012] The technical problems of the embodiments disclosed in this document are not limited to the above technical problems, and those of ordinary skill in the art will clearly understand other unmentioned technical problems from the following description.

[0013] Technical Solution

[0014] A battery diagnostic device according to an embodiment disclosed herein includes: an acquisition unit configured to acquire a first voltage value of each of a plurality of battery cells; an identification unit configured to identify a second voltage value in different idle periods from the first voltage values; a determination unit configured to determine a voltage gradient indicating a degree of change over time of the second voltage value of each of the plurality of battery cells, and determine a standard score (Z-score) of the voltage gradient of each of the plurality of battery cells by using an average value and a standard deviation of a plurality of voltage gradients corresponding one-to-one to the plurality of battery cells; and a diagnosis unit configured to select battery cells among the plurality of battery cells whose standard scores are outside a first reference range and whose voltage gradients are outside a second reference range, and diagnose at least some of the selected battery cells as abnormal battery cells.

[0015] In the battery diagnostic device according to an embodiment disclosed herein, the determination unit may further be configured to: determine an average voltage value of the different idle periods of each of the plurality of battery cells based on the second voltage value; and determine the voltage gradient based on the average voltage value.

[0016] In the battery diagnostic device according to an embodiment disclosed herein, the diagnosis unit may further be configured to: when the different idle periods are different post-charge idle periods, select battery cells among the plurality of battery cells whose standard scores are greater than an upper limit of the first reference range and whose voltage gradients are greater than a second upper limit of the second reference range, and diagnose at least some of the selected battery cells as abnormal battery cells.

[0017] In the battery diagnostic device according to an embodiment disclosed herein, the diagnosis unit may further be configured to: when the different idle periods are different post-discharge idle periods, select battery cells among the plurality of battery cells whose standard scores are less than a lower limit of the first reference range and whose voltage gradients are less than a second lower limit of the second reference range, and diagnose at least some of the selected battery cells as abnormal battery cells.

[0018] In the battery diagnosis device according to the embodiments disclosed herein, the diagnosis unit may also be configured to diagnose a battery cell as an abnormal battery cell if the difference between the maximum value and the minimum value of the second voltage value in the selected battery cells is greater than a specified difference.

[0019] In the battery diagnosis device according to the embodiments disclosed herein, the identification unit may also be configured to set the different idle periods as periods during which the voltage value, current value, charge amount, and / or discharge amount are within a specified range.

[0020] The battery diagnosis device according to the embodiments disclosed herein may further include an abnormality processing unit configured to perform an abnormality processing function based on the abnormality diagnosis results of each of the plurality of battery cells, wherein the abnormality processing function includes a notification function or a short-circuit function.

[0021] A battery diagnosis method according to the embodiments disclosed herein includes: obtaining a first voltage value of each of a plurality of battery cells; identifying a second voltage value in different idle periods from the first voltage values; determining a voltage gradient indicating the degree of change over time of the second voltage value of each of the plurality of battery cells; determining a standard score (Z-score) of the voltage gradient of each of the plurality of battery cells by using an average value and a standard deviation of a plurality of voltage gradients corresponding one-to-one to the plurality of battery cells; selecting battery cells from the plurality of battery cells whose standard scores are outside a first reference range and whose voltage gradients are outside a second reference range; and diagnosing at least some of the selected battery cells as abnormal battery cells.

[0022] In the battery diagnosis method according to the embodiments disclosed herein, the determination of the voltage gradient may include: determining an average voltage value of the different idle periods of each of the plurality of battery cells based on the second voltage value; and determining the voltage gradient based on the average voltage value.

[0023] In the battery diagnosis method according to the embodiments disclosed herein, selecting battery cells may include: when the different idle periods are different post-charge idle periods, selecting battery cells from the plurality of battery cells whose standard scores are greater than an upper limit of the first reference range and whose voltage gradients are greater than an upper limit of the second reference range.

[0024] In the battery diagnosis method according to the embodiments disclosed herein, selecting a battery cell may include: when the different idle periods are different post-discharge idle periods, selecting, from the plurality of battery cells, a battery cell whose standard score is less than a lower limit of the first reference range and whose voltage gradient is less than a lower limit of the second reference range.

[0025] In the battery diagnosis method according to the embodiments disclosed herein, diagnosing at least some of the selected battery cells as abnormal battery cells may include: diagnosing, as an abnormal battery cell, a battery cell in the selected batteries in which a difference between a maximum value and a minimum value of the second voltage value is greater than a specified difference.

[0026] The battery diagnosis method according to the embodiments disclosed herein may further include setting the different idle periods as periods during which a voltage value, a current value, a charge amount, and / or a discharge amount are within a specified range.

[0027] The battery diagnosis method according to the embodiments disclosed herein may further include performing an abnormality handling function based on an abnormality diagnosis result of each battery cell in the plurality of battery cells, where the abnormality handling function includes a notification function or a short-circuit function.

[0028] Advantageous Effects

[0029] A battery diagnosis device and an operation method thereof according to various embodiments disclosed herein can detect the occurrence of an internal short circuit of a battery or other types of faults.

[0030] A battery diagnosis device and an operation method thereof according to various embodiments disclosed herein can handle another type of short circuit or fault inside the detected battery.

[0031] The effects of the battery abnormality diagnosis device and the operation method thereof according to the present document are not limited to the above effects, and those of ordinary skill in the art will clearly understand other effects not mentioned based on the content disclosed in the present document.

[0032] In addition, various effects directly or indirectly recognized from the present disclosure can be provided. Brief Description of the Drawings

[0033] Figure 1 A graph showing a difference between a degree of voltage change of a normal battery cell and a degree of voltage change of an abnormal battery cell during an idle period.

[0034] Figure 2 A block diagram of a battery diagnosis device according to an embodiment.

[0035] Figure 3ais a graph showing an example of setting an idle period after charging a battery cell according to one embodiment.

[0036] Figure 3b is a graph showing an example of setting an idle period after discharging a battery cell according to one embodiment.

[0037] Figure 4 is a graph showing an example of diagnosing an abnormality based on a standard score of a battery cell according to one embodiment.

[0038] Figure 5 is an operation flowchart of a battery diagnosis device according to one embodiment.

[0039] Figure 6 is an operation flowchart of a battery diagnosis device according to one embodiment. Detailed Embodiments

[0040] Hereinafter, various embodiments of the present disclosure will be disclosed with reference to the accompanying drawings. However, the description is not intended to limit the present disclosure to specific embodiments and should be construed as including various modifications, equivalents, and / or alternatives according to the embodiments of the present disclosure.

[0041] It should be understood that the various embodiments of this document and the terms used therein are not intended to limit the technical features set forth herein to specific embodiments and include various changes, equivalents, or substitutions of the corresponding embodiments. Regarding the description of the drawings, like reference numerals may be used to refer to like or related elements. It should be understood that the singular form of the noun corresponding to an item may include one or more things unless the relevant context clearly indicates otherwise.

[0042] As used herein, each of the phrases such as "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" may include any one or all possible combinations of the items enumerated together in the corresponding one of the phrases. Unless otherwise specified, terms such as "first", "second", "the first", "the second", "A", "B", "(a)", or "(b)" may be used simply to distinguish the corresponding components from each other and do not limit the components in other respects (e.g., importance or order).

[0043] In this document, it should be understood that when an element (e.g., a first element) is referred to as being connected, coupled, linked, or joined to or connected to another element (e.g., a second element) with or without the terms "operably" or "communicatively", this means that the element can be directly (e.g., wired), wirelessly, or via a third element connected to the other element.

[0044] According to embodiments of the present disclosure, methods according to various embodiments of the present disclosure disclosed herein may be included and provided in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., a compact disc read-only memory (CD-ROM)), or distributed online via an app store (e.g., downloaded or uploaded), or directly distributed between two user devices. If distributed online, at least a portion of the computer program product may be generated temporarily or stored at least temporarily in a machine-readable storage medium, such as the memory of a manufacturer server, the server of an app store, or a relay server.

[0045] According to various embodiments, each of the above components (e.g., a module or a program) may include a single entity or multiple entities, and some of the multiple entities may be separately provided in different components. According to various embodiments, one or more of the above components may be omitted, or one or more other components may be added. Alternatively or additionally, multiple components (e.g., modules or programs) may be integrated into a single component. In this case, according to various embodiments, the integrated component may still perform one or more functions of each of the multiple components in the same or similar manner as the corresponding components of the multiple components performed the functions before integration. According to various embodiments, operations performed by a module, a program, or another component may be executed sequentially, in parallel, repeatedly, or heuristically, or one or more operations may be executed in a different order or omitted, or one or more other operations may be added.

[0046] Figure 1 A graph showing the difference in the degree of voltage change between a normal battery cell and an abnormal battery cell during an idle period is shown.

[0047] Reference Figure 1 , it can be seen that graph 10 shows the voltage 11 of a normal battery cell and the voltage 13 of an abnormal battery cell. From graph 10, it can be seen that for the voltage 11 of a normal battery cell, the voltage value difference is relatively small during each idle period (e.g., the idle period after charging or discharging) when the voltage value remains constant. On the other hand, from graph 10, it can be seen that for the voltage 13 of an abnormal battery cell, the voltage value difference is relatively large during each idle period. For example, for the voltage 13 of an abnormal battery cell, the voltage value may increase significantly as the idle period continues after charging. For example, for the voltage 13 of an abnormal battery cell, the voltage value may decrease significantly as the idle period continues after discharging. When a short circuit or other type of fault occurs inside the battery cell, abnormal behavior similar to the voltage 13 of the abnormal battery cell may occur.

[0048] Therefore, since the battery cells exhibit abnormal behavior similar to that of the abnormal battery cell 13, damage to the electronic device may occur. Therefore, a battery cell with abnormal behavior can be detected from the battery cells, and appropriate processing may be required.

[0049] Figure 2 is a block diagram of a battery diagnosis device according to an embodiment.

[0050] Reference Figure 2 , the battery diagnosis device 101 can be connected to the electronic device 103 and the user terminal 105 wired and / or wirelessly.

[0051] In one embodiment, the connection 104 between the battery diagnosis device 101 and the electronic device 103 can be a communication connection via a wired and / or wireless network. In one embodiment, the wired network can be based on local area network (LAN) communication or power line communication. In one embodiment, the wireless network can be based on a short-range communication network (e.g., Bluetooth, wireless fidelity (WiFi), or infrared data association (IrDA)) or a long-range communication network (e.g., a cellular network, a fourth-generation (4G) network, a fifth-generation (5G) network).

[0052] In another embodiment, the connection 104 between the battery diagnosis device 101 and the electronic device 103 can be a connection using a device-to-device communication scheme (e.g., a bus, a general-purpose input / output (GPIO), a serial peripheral interface (SPI), or a mobile industry processor interface (MIPI)).

[0053] In one embodiment, the connection 106 between the battery diagnosis device 101 and the user terminal 105 can be a communication connection via a wired and / or wireless network.

[0054] In one embodiment, the electronic device 103 can be a mobile device (e.g., a mobile phone, a laptop computer, a smartphone, a smart board), an electric vehicle (e.g., an electric vehicle (EV), a hybrid EV (HEV), a plug-in HEV (PHEV), a fuel cell EV (FCEV)), an energy storage system (ESS), or a battery swapping system (BSS).

[0055] In one embodiment, the electronic device 103 can include one or more battery cells 111, 113, and 115. Each of the one or more battery cells 111, 113, and 115 can be a battery cell, a battery module, a battery pack, or a battery rack.

[0056] In one embodiment, the user terminal 105 may be a mobile device (e.g., a mobile phone, a laptop computer, a smart phone, a smart board) or a personal computer (PC).

[0057] In one embodiment, the battery diagnostic device 101 may include a communication circuit 120, a sensor 130, a memory 140, and a processor 150. According to one embodiment, in addition to Figure 2 the components shown in Figure 2 the battery diagnostic device 101 shown in may further include at least one component (e.g., a display, an input device, or an output device).

[0058] In one embodiment, the communication circuit 120 may establish a wired communication channel and / or a wireless communication channel between the battery diagnostic device 101 and the electronic device 103 and / or the user terminal 105, and transmit data to the electronic device 103 and / or the user terminal 105 and receive data from the electronic device 103 and / or the user terminal 105 via the established communication channel.

[0059] In one embodiment, the sensor 130 may obtain values related to the states of the battery cells 111, 113, and 115 of the electronic device 103. In one embodiment, the values related to the states may indicate one or more of the voltage, current, resistance, state of charge (SoC), state of health (SoH), or temperature values of the battery cells 111, 113, and 115 or a combination thereof. Hereinafter, the values related to the states may be referred to as "state values".

[0060] In one embodiment, the memory 140 may include volatile and / or non-volatile memory.

[0061] In one embodiment, the memory 140 may store data used by at least one component of the battery diagnostic device 101 (e.g., the processor 150). For example, the data may include software (or related instructions), input data, or output data. In one embodiment, when executed by the processor 150, the instructions may cause the battery anomaly diagnostic device 101 to perform the operations defined by the instructions.

[0062] In one embodiment, the memory 140 may include one or more software (e.g., an acquisition unit 141, an identification unit 143, a determination unit 145, a diagnostic unit 147, and an anomaly processing unit 149).

[0063] In one embodiment, the processor 150 may include a central processing unit, an application processor, a graphics processing unit, a neural processing unit (NPU), an image signal processor, a sensor hub processor, or a communication processor.

[0064] In one embodiment, the processor 150 may execute software (e.g., the acquisition unit 141, the identification unit 143, the determination unit 145, the diagnosis unit 147, and the exception handling unit 149) to control at least one other component (e.g., a hardware or software component) of the battery diagnosis device 101 connected to the processor 150 and perform various data processing or operations.

[0065] Hereinafter, with reference to Figure 3a 、 Figure 3b and Figure 4 , a method for diagnosing an abnormality of the battery cells 111, 113, and 115 by the battery diagnosis device 101 using the acquisition unit 141, the identification unit 143, the determination unit 145, the diagnosis unit 147, and / or the exception handling unit 149 will be described.

[0066] Figure 3a is a graph showing an example of setting an idle period after charging a battery cell according to one embodiment. Figure 3b is a graph showing an example of setting an idle period after discharging a battery cell according to one embodiment. Figure 4 is a graph showing an example of diagnosing an abnormality based on a standard score of a battery cell according to one embodiment. The components of Figure 2 will be described using Figure 3a 、 Figure 3b and Figure 4 .

[0067] In one embodiment, the acquisition unit 141 may acquire first voltage values corresponding to the plurality of battery cells 111, 113, and 115. In one embodiment, the acquisition unit 141 may acquire a plurality of voltage distributions respectively indicating voltage changes of the plurality of battery cells 111, 113, and 115 over time. The acquisition unit 141 may acquire the first voltage values based on the acquired plurality of voltage distributions.

[0068] In one embodiment, the acquisition unit 141 may acquire the first voltage values corresponding to the plurality of battery cells 111, 113, and 115 by means of an electronic device 103 connected through a wired and / or wireless network.

[0069] In one embodiment, the identification unit 143 may identify second voltage values in different idle periods from the first voltage values. In one embodiment, the identification unit 143 may set different idle periods as periods during which the voltage value, current value, charge amount, and / or discharge amount are within a specified range. The identification unit 143 may extract different idle periods of each of the plurality of battery cells 111, 113, and 115 from the acquired plurality of voltage distributions, and identify the second voltage values in the corresponding periods of the plurality of corresponding battery cells 111, 113, and 115.

[0070] In one embodiment, the different idle periods can be different post - charge idle periods or different post - discharge idle periods.

[0071] For example, referring to Figure 3a , the charging period S1 and the post - charge idle period S2 can be seen from the curve graph 310. In one embodiment, the identification unit 143 can identify the charging period S1 with a specified charge amount from the respective SOC distributions of the plurality of battery cells 111, 113, and 115. To this end, the acquisition unit 141 can acquire the respective SOC profiles of the plurality of battery cells 111, 113, and 115 by means of an electronic device 103 connected via a wired and / or wireless network. In one embodiment, the identification unit 143 can extract the post - charge idle period S2 based on the voltage value and / or current value of each of the plurality of battery cells 111, 113, and 115 after the charging period S1. For example, the identification unit 143 can extract the period during which the current value of the battery cell 111, 113, or 115 is within a first current range (for example, a range of 0 A to 1 A) as the post - charge idle period S2.

[0072] In another embodiment, referring to Figure 3b , the discharging period S3 and the post - discharge idle period S4 can be seen from the curve graph 320. In one embodiment, the identification unit 143 can identify the discharging period S3 with a specified discharge amount from the respective SOCs of the plurality of battery cells 111, 113, and 115. In one embodiment, the identification unit 143 can extract the post - discharge idle period S4 based on the voltage value and / or current value of each of the plurality of battery cells 111, 113, and 115 after the discharging period S3. For example, the identification unit 143 can extract the period during which the current value of the battery cell 111, 113, or 115 is within a second current range (for example, a range of - 1 A to 0 A) as the post - charge idle period S2.

[0073] In one embodiment, the identification unit 143 can identify the second voltage value of each of the plurality of phase battery cells 111, 113, and 115 in the different extracted idle periods (for example, different post - charge idle periods or different post - discharge idle periods).

[0074] In one embodiment, the determining unit 145 may determine the voltage gradient over time of the respective second voltage values of the plurality of battery cells 111, 113, and 115. In one embodiment, the determining unit 145 may determine the average voltage value of each of the plurality of battery cells 111, 113, and 115 during different idle periods (e.g., different post-charge idle periods or different post-discharge idle periods) based on the second voltage value. The determining unit 145 may determine the voltage gradient based on the average voltage value. For example, the determining unit 145 may determine the average voltage value of each of the plurality of battery cells 111, 113, and 115 during different post-charge idle periods, as shown in Table 1 below.

[0075] [Table 1]

[0076]

[0077] Referring to Table 1, even when the post-charge idle period continues, the average voltage of battery cell 111 remains constant, such as 4.0514, 4.0513, and 4.0513, while the average voltage of battery cell 113 relatively increases even when the post-charge idle period continues, such as 4.0502, 4.5028, and 4.0566.

[0078] In another embodiment, the determining unit 145 may determine the average voltage value of each of the plurality of battery cells 111, 113, and 115 during different post-discharge idle periods, as shown in Table 2 below.

[0079] Table 2

[0080]

[0081] Referring to Table 2, even when the post-discharge idle period continues, the average voltage of battery cell 111 remains constant, e.g., 3.5122, 3.5122, and 3.5122, while the average voltage of battery cell 113 relatively increases even when the post-discharge idle period continues, e.g., 3.5125, 3.5157, and 3.5191.

[0082] In one embodiment, the determining unit 145 may determine the voltage gradient based on a linear regression scheme. For example, the determining unit 145 may determine the plurality of corresponding voltage gradients of the plurality of battery cells 111, 113, and 115 based on a linear regression scheme by using all the respective second voltage values of the plurality of battery cells 111, 113, and 115 as input factors. In another embodiment, the determining unit 145 may determine the plurality of voltage gradients based on a linear regression scheme by using the average voltage values during different idle periods of each of the plurality of battery cells 111, 113, and 115 as input factors.

[0083] In one embodiment, the determination unit 145 can determine the standard score of the voltage gradient of each of the plurality of battery cells 111, 113, and 115 by using the average value and the standard deviation of the plurality of voltage gradients corresponding one-to-one to the plurality of battery cells 111, 113, and 115. For example, the determination unit 145 can determine the standard score according to Equation 1.

[0084] [Equation 1]

[0085]

[0086] In Equation 1, z represents the standard score of the voltage gradient of the battery cell 111, 113, or 115, x represents the voltage gradient of the battery cell 111, 113, or 115, μ represents the average value of the plurality of voltage gradients corresponding one-to-one to the plurality of battery cells 111, 113, and 115, and σ represents the standard deviation.

[0087] In one embodiment, the diagnosis unit 147 can select the battery cells whose standard scores are outside the first reference range and whose voltage gradients are outside the second reference range from the plurality of battery cells 111, 113, and 115. For example, referring to Figure 4 , the diagnosis unit 147 can diagnose all battery cells whose standard scores are outside the first reference range in the curve graph 400 as abnormal battery cells.

[0088] For example, when the different idle periods are different post-charge idle periods, the diagnosis unit 147 can select the battery cells whose standard scores are greater than the first upper limit of the first reference range and whose voltage gradients are greater than the second upper limit of the second reference range from the plurality of battery cells 111, 113, and 115.

[0089] In another embodiment, when the different idle periods are different post-charge idle periods, the diagnosis unit 147 can select the battery cells whose standard scores are less than the first lower limit of the first reference range and whose voltage gradients are less than the second lower limit of the second reference range from the plurality of battery cells 111, 113, and 115.

[0090] In one embodiment, the diagnosis unit 147 can diagnose at least some of the selected battery cells as abnormal battery cells. In one embodiment, the diagnosis unit 147 can diagnose as abnormal battery cells those battery cells in the selected battery cells for which the difference between the maximum value and the minimum value of the second voltage value is greater than a specified difference.

[0091] In one embodiment, the diagnosis unit 147 can diagnose the abnormality of the battery cells based on the voltage gradient, the standard score of the voltage gradient, and the difference between the maximum value and the minimum value of each of the plurality of battery cells 111, 113, and 115, as shown in Table 3.

[0092] Table 3

[0093]

[0094] For example, when the different idle periods are post-discharge idle periods, the first reference range is from -3 to 3, the second reference range is from -0.01 to 0.01, and the specified difference is 0.04. Then, the battery cell 113 in Table 3 has a standard score of -3.6055 outside the first reference range, a voltage gradient of -0.003 outside the second reference range, and the difference between the maximum value and the minimum value is 0.045, which is greater than the specified difference. Thus, the diagnosis unit 147 can diagnose the battery cell 113 as an abnormal battery cell.

[0095] In one embodiment, the abnormality handling unit 149 can perform an abnormality handling function based on the abnormality diagnosis results of the plurality of battery cells 111, 113, and 115. In one embodiment, the abnormality handling function can include a notification function or a short-circuit function.

[0096] For example, the abnormality handling unit 149 can send the abnormality diagnosis results of the plurality of battery cells 111, 113, and 115 to the user terminal 105 connected via a wired and / or wireless network.

[0097] In another embodiment, the abnormality handling unit 149 can isolate the abnormal battery cell from the electronic device 103 based on the abnormality diagnosis results of the plurality of battery cells 111, 113, and 115. Here, the isolation can include electrical and / or mechanical isolation.

[0098] Figure 5 is an operation flowchart of a battery diagnosis device according to one embodiment. The components of Figure 2 will be used to describe Figure 5 .

[0099] Figure 5 The embodiments shown in Figure 5 can be examples, and the order of operations according to various embodiments of the present disclosure can be different from Figure 5 shown in

[0100] Some operations shown in Figure 5 can be omitted, the order of operations can be changed, or the operations can be combined.

[0101] In one embodiment, the battery diagnostic device 101 may obtain the first voltage value of each of the plurality of battery cells 111, 113, and 115 via an electronic device 103 connected by a wired and / or wireless network.

[0102] In operation 510, the battery diagnostic device 101 may identify the second voltage values in different idle periods from the first voltage values obtained in operation 505. In one embodiment, the battery diagnostic device 101 may set different idle periods as periods during which the voltage value, current value, charge amount, and / or discharge amount are within a specified range. The battery diagnostic device 101 may extract different idle periods of each of the plurality of battery cells 111, 113, and 115 from the obtained plurality of voltage distributions, and identify the second voltage values of each of the plurality of battery cells 111, 113, and 115 during the corresponding periods.

[0103] In one embodiment, the different idle periods may be different post - charge idle periods or different post - discharge idle periods.

[0104] In operation 515, the battery diagnostic device 101 may determine the voltage gradient over time of the second voltage value of each of the plurality of battery cells 111, 113, and 115. In one embodiment, the battery diagnostic device 101 may determine the average voltage value of different idle periods (e.g., different post - charge idle periods or different post - discharge idle periods) of each of the plurality of battery cells 111, 113, and 115 based on the second voltage value. The battery diagnostic device 101 may determine the voltage gradient based on the average voltage value.

[0105] In one embodiment, the battery diagnostic device 101 may determine the voltage gradient based on a linear regression scheme. For example, the battery diagnostic device 101 may use all the second voltage values of each of the plurality of battery cells 111, 113, and 115 as input factors, and determine the plurality of voltage gradients of each of the plurality of battery cells 111, 113, and 115 based on the linear regression scheme. In another embodiment, the battery diagnostic device 101 may use the average voltage value in different idle periods of each of the plurality of battery cells 111, 113, and 115 as an input factor to determine the plurality of voltage gradients based on the linear regression scheme.

[0106] In operation 520, the battery diagnostic device 101 may determine the standard score of the voltage gradient of each of the plurality of battery cells 111, 113, and 115 by using the average value and standard deviation of the plurality of voltage gradients corresponding one - to - one to the plurality of battery cells 111, 113, and 115.

[0107] In operation 525, the battery diagnostic device 101 may diagnose an abnormality of each of the plurality of battery cells 111, 113, and 115. In one embodiment, the battery diagnostic device 101 may diagnose an abnormality of each of the plurality of battery cells 111, 113, and 115 based on the voltage gradient determined in operation 515 and the standard score determined in operation 520.

[0108] Reference will be made Figure 6 to describe in more detail operation 525 of diagnosing an abnormality of each of the plurality of battery cells 111, 113, and 115 by the battery diagnostic device.

[0109] Figure 6 is an operation flowchart of a battery diagnostic device according to one embodiment. Components of Figure 2 will be used to describe Figure 6 .

[0110] Figure 6 The embodiments shown in Figure 6 may be examples, and the order of operations according to various embodiments of the present disclosure may be different from Figure 6 the order shown in Figure 6 , and some operations shown in

[0111] In operation 605, the battery diagnostic device 101 may identify whether the standard score of the voltage gradient of the battery cell 111, 113, or 115 is outside a first reference range. For example, when different idle periods are different post-charge idle periods, the battery diagnostic device 101 may identify whether the standard score of the voltage gradient of the battery cell 111, 113, or 115 is greater than the first upper limit of the first reference range. In another embodiment, when different idle periods are different post-discharge idle periods, the battery diagnostic device 101 may identify whether the standard score of the voltage gradient of the battery cell 111, 113, or 115 is less than the first lower limit of the first reference range.

[0112] When the standard score of the voltage gradient of the battery cell 111, 113, or 115 is identified as being within the first reference range ("No") in operation 605, the battery diagnostic device 101 may diagnose the battery cell 111, 113, or 115 as a normal battery cell in operation 610.

[0113] When the z-score of the voltage gradient of battery cells 111, 113, or 115 is identified as being outside the first reference range (“Yes”) in operation 605, the battery diagnostic device 101 may identify whether the voltage gradient of battery cells 111, 113, or 115 is less than a second reference value in operation 615. For example, when different idle periods are different post-charge idle periods, the battery diagnostic device 101 may identify whether the voltage gradient of battery cells 111, 113, or 115 is greater than the second upper limit of the second reference range. In another embodiment, when different idle periods are different post-discharge idle periods, the battery diagnostic device 101 may identify whether the voltage gradient of battery cells 111, 113, or 115 is less than the second lower limit of the second reference range.

[0114] When the voltage gradient of battery cells 111, 113, or 115 is identified as being within the second reference range (“No”) in operation 615, the battery diagnostic device 101 may diagnose battery cells 111, 113, or 115 as normal battery cells in operation 610.

[0115] When the voltage gradient of battery cells 111, 113, or 115 is identified as being outside the second reference range (“Yes”) in operation 615, the battery diagnostic device 101 may identify whether the difference between the maximum value and the minimum value of the second voltage values of battery cells 111, 113, or 115 exceeds a specified difference in operation 620.

[0116] When the difference between the maximum value and the minimum value of the second voltage values of battery cells 111, 113, or 115 is identified as being less than the specified difference (“No”) in operation 620, the battery diagnostic device 101 may diagnose battery cells 111, 113, or 115 as normal battery cells in operation 610.

[0117] When the difference between the maximum value and the minimum value of the second voltage values of battery cells 111, battery cell 113, or battery cell 115 is identified as exceeding the specified difference (“Yes”) in operation 620, the battery diagnostic device 101 may diagnose battery cells 111, 113, or 115 as abnormal battery cells in operation 625.

[0118] Unless otherwise specified, terms such as "comprising", "consisting of", or "having" above may mean that the corresponding components may be inherent, and thus should be construed as further including other components rather than excluding other components. Unless otherwise defined, all terms including technical or scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments disclosed herein belong. Commonly used terms, like the terms defined in a dictionary, should be construed to have the same meaning as the context of the relevant art and should not be construed to have an ideal or overly formal meaning unless they are explicitly defined in this document.

Claims

1. A battery diagnosis device, the battery diagnosis device comprising: An acquisition unit configured to acquire a first voltage value of each of a plurality of battery cells; An identification unit configured to identify a second voltage value in different idle periods from the first voltage values; A determination unit configured to determine a voltage gradient indicating a degree of change over time of the second voltage value of each of the plurality of battery cells, and determine a standard score Z-score of the voltage gradient of each of the plurality of battery cells by using an average value and a standard deviation of a plurality of voltage gradients corresponding one-to-one to the plurality of battery cells; And A diagnosis unit configured to select battery cells whose standard scores are outside a first reference range and whose voltage gradients are outside a second reference range from the plurality of battery cells, and diagnose at least some of the selected battery cells as abnormal battery cells.

2. The battery diagnosis device according to claim 1, wherein, The determination unit is further configured to: Determine an average voltage value of the different idle periods of each of the plurality of battery cells based on the second voltage value; and Determine the voltage gradient based on the average voltage value.

3. The battery diagnosis device according to claim 1, wherein, The diagnosis unit is further configured to: when the different idle periods are different post-charge idle periods, select battery cells whose standard scores are greater than an upper limit of the first reference range and whose voltage gradients are greater than a second upper limit of the second reference range from the plurality of battery cells, and diagnose at least some of the selected battery cells as abnormal battery cells.

4. The battery diagnosis device according to claim 1, wherein, The diagnosis unit is further configured to: when the different idle periods are different post-discharge idle periods, select battery cells whose standard scores are less than a lower limit of the first reference range and whose voltage gradients are less than a second lower limit of the second reference range from the plurality of battery cells, and diagnose at least some of the selected battery cells as abnormal battery cells.

5. The battery diagnosis device according to claim 1, wherein, The diagnosis unit is further configured to diagnose as abnormal battery cells battery cells among the selected battery cells whose difference between a maximum value and a minimum value of the second voltage value is greater than a specified difference.

6. The battery diagnosis device according to claim 1, wherein, The identification unit is further configured to set the different idle periods as periods during which a voltage value, a current value, a charge amount, and / or a discharge amount are within a specified range.

7. The battery diagnosis device according to claim 1, the battery diagnosis device further comprising an exception handling unit configured to perform an exception handling function based on the exception diagnosis result of each battery cell in the plurality of battery cells, wherein, The abnormal handling function includes a notification function or a short-circuit function.

8. A battery diagnosis method, the battery diagnosis method comprising the following steps: Acquire a first voltage value of each of a plurality of battery cells; Identify a second voltage value in different idle periods from the first voltage values; Determine a voltage gradient indicating a degree of change over time of the second voltage value of each of the plurality of battery cells; Determine a standard score Z-score of the voltage gradient of each of the plurality of battery cells by using an average value and a standard deviation of a plurality of voltage gradients corresponding one-to-one to the plurality of battery cells; Select battery cells whose standard scores are outside a first reference range and whose voltage gradients are outside a second reference range from the plurality of battery cells; And Diagnose at least some of the selected battery cells as abnormal battery cells.

9. The battery diagnosis method according to claim 8, wherein, The step of determining the voltage gradient includes the following steps: Based on the second voltage value, determine the average voltage value of each of the plurality of battery cells during the different idle periods; and Determine the voltage gradient based on the average voltage value.

10. The battery diagnosis method according to claim 8, wherein, The step of selecting a battery cell includes: when the different idle periods are different post-charge idle periods, selecting, from the plurality of battery cells, a battery cell whose standard score is greater than the upper limit of the first reference range and whose voltage gradient is greater than the upper limit of the second reference range.

11. The battery diagnosis method according to claim 8, wherein, The step of selecting a battery cell includes: when the different idle periods are different post-discharge idle periods, selecting, from the plurality of battery cells, a battery cell whose standard score is less than the lower limit of the first reference range and whose voltage gradient is less than the lower limit of the second reference range.

12. The battery diagnosis method according to claim 8, wherein,The step of diagnosing at least some of the selected battery cells as abnormal battery cells includes: diagnosing as an abnormal battery cell a battery cell in the selected batteries whose difference between the maximum value and the minimum value of the second voltage value is greater than a specified difference.

13. The battery diagnosis method according to claim 8, wherein the battery diagnosis method further comprises setting the different idle periods as periods in which a voltage value, a current value, a charge amount, and / or a discharge amount are within a specified range.

14. The battery diagnosis method according to claim 8, wherein the battery diagnosis method further comprises performing an abnormality handling function based on the abnormality diagnosis result of each battery cell among the plurality of battery cells. wherein The abnormal handling function includes a notification function or a short-circuit function.

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