Method, recording medium, and apparatus for diagnosing assembly defect of battery pack

Abstract

Provided are a method, a recording medium, and an apparatus for diagnosing an assembly defect of a battery pack, the method including: calculating an internal resistance value of a battery module including a battery cell in the battery pack; calculating an internal resistance value of a battery control unit (BCU) in the battery pack and configured to control charging or discharging of the battery module; and comparing a first voltage value of the battery pack with a second voltage value of the battery pack, the first voltage value being calculated based on the internal resistance value of the battery module and the internal resistance value of the BCU, and the second voltage value being a measured voltage value of the battery pack.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0108262 filed in the Korean Intellectual Property Office on August 18, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] One or more embodiments are directed to methods, computer programs, and apparatus for diagnosing assembly defects of a battery. Background Art

[0004] Recently, with the rapid increase in demand for portable electronic products such as laptop computers, cameras and mobile phones and with the intensive development of energy storage batteries, robots and satellites, etc., research on high-performance secondary batteries that can be repeatedly charged / discharged (i.e., charged or discharged) has been actively conducted.

[0005] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries, etc. Among them, lithium secondary batteries have almost no memory effect compared to nickel-based secondary batteries, and therefore have attracted attention due to their advantages of free charge / discharge, very low self-discharge rate, and high energy density.

[0006] For example, recently, with the continuous depletion of carbon energy and the increasing concern about environmental issues, the demand for hybrid vehicles and electric vehicles has gradually increased around the world including the United States, Europe, Japan and South Korea. A hybrid vehicle or an electric vehicle obtains vehicle driving power by using the charging / discharging energy of a battery pack. Compared with a vehicle driven by an engine alone, a hybrid vehicle or an electric vehicle has higher fuel efficiency and can eliminate or reduce the emission of pollutants, and therefore has received positive responses from many consumers. More attention and research have been focused on vehicle batteries, which are key components of hybrid vehicles or electric vehicles.

[0007] The battery pack includes various components including a battery module including a plurality of battery cells. During assembly, such battery modules and components may be connected to each other by welding, bolting or connection, etc., and therefore, assembly defects may occur during the connection. Summary of the invention

[0008] One or more embodiments include a method, a computer program, and an apparatus for diagnosing an assembly defect of a battery to effectively diagnose the assembly defect in a process of diagnosing the assembly defect of a battery pack.

[0009] However, such purpose is merely an example, and the scope of the present disclosure is not limited thereto.

[0010] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0011] According to one or more embodiments, a method for diagnosing an assembly defect of a battery pack includes: calculating an internal resistance value of a battery module including battery cells in the battery pack; calculating an internal resistance value of a battery control unit (BCU) in the battery pack and configured to control charging or discharging of the battery module; and comparing a first voltage value of the battery pack with a second voltage value of the battery pack, the first voltage value being calculated based on the internal resistance value of the battery module and the internal resistance value of the BCU, and the second voltage value being a measured voltage value of the battery pack.

[0012] The calculation of the internal resistance value of the battery module may include using both ends of the battery module as measurement points.

[0013] The calculation of the internal resistance value of the battery module may be based on a change amount of the internal resistance value of the battery module corresponding to the battery degradation state, the change amount of the internal resistance value of the battery module corresponding to the battery cell model.

[0014] The method may further include: calculating an internal resistance value of the battery pack by adding an internal resistance value of the battery module and an internal resistance value of the BCU based on a current degradation state, the internal resistance value of the battery module reflecting an amount of change in the internal resistance value according to the battery degradation state; calculating a first voltage value by multiplying the internal resistance value of the battery pack by a value of a current flowing through both ends of the battery pack; and comparing an amplitude of the first voltage value with an amplitude of a second voltage value, the second voltage value being obtained by measuring the voltage at both ends of the battery pack.

[0015] The method may further include determining that a magnitude of the second voltage value is greater than a magnitude of the first voltage value.

[0016] The calculation of the internal resistance value of the BCU may be based on using measurement points for components in the BCU.

[0017] One or more embodiments provide a computer-readable recording medium on which a computer program for executing the method by using a computing device is stored.

[0018] According to one or more embodiments, an apparatus for diagnosing an assembly defect of a battery pack includes: a battery module in the battery pack and including battery cells; a battery control unit (BCU) in the battery pack and configured to control charging or discharging of the battery module; and a processor configured to calculate an internal resistance value of the battery module, calculate an internal resistance value of the BCU, and diagnose an assembly defect of the battery pack by comparing a first voltage value of the battery pack with a second voltage value of the battery pack, the first voltage value being calculated based on the internal resistance value of the battery module and the internal resistance value of the BCU, and the second voltage value being a measured voltage value of the battery pack.

[0019] The processor may be further configured to use both ends of the battery module as measurement points.

[0020] The processor may be further configured to calculate an internal resistance value of the battery module based on a change amount of the internal resistance value of the battery module corresponding to the battery degradation state, the change amount of the internal resistance value of the battery module corresponding to the battery cell model.

[0021] The processor can be further constructed to: calculate the internal resistance value of the battery pack by adding the internal resistance value of the battery module and the internal resistance value of the BCU based on the current degradation state, the internal resistance value of the battery module reflects the change in the internal resistance value according to the battery degradation state; calculate a first voltage value by multiplying the internal resistance value of the battery pack by the value of the current flowing through the two ends of the battery pack; and compare the amplitude of the first voltage value with the amplitude of the second voltage value, the second voltage value is obtained by measuring the voltage at the two ends of the battery pack.

[0022] The processor may be further configured to diagnose the presence of an assembly defect in the battery pack when the magnitude of the second voltage value is greater than the magnitude of the first voltage value.

[0023] The processor may be further configured to calculate an internal resistance value of the BCU based on using measurement points for components assembled and provided in the BCU. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other aspects of certain embodiments of the present disclosure will become more apparent through the following description in conjunction with the accompanying drawings, in which:

[0025] Figure 1 Schematically illustrates a battery pack according to an embodiment of the present disclosure;

[0026] Figure 2 is a diagram for explaining a method of diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure;

[0027] Figure 3 is a flowchart for explaining a method of diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure; and

[0028] Figure 4 is a graph for explaining a change amount of an internal resistance value according to a battery degradation state according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0029] By referring to the detailed description and drawings of the embodiments, it is easier to understand some embodiments of the present disclosure and aspects of the methods for implementing the same. The described embodiments are provided as examples so that the present disclosure will be thorough and complete, and will fully convey aspects of the present disclosure to those skilled in the art. Processes, elements and techniques that are redundant, irrelevant or unrelated to the description of the embodiments or are not necessary for a complete understanding of aspects of the present disclosure by those of ordinary skill in the art can be omitted. Unless otherwise stated, throughout the drawings and written descriptions, the same reference numerals, characters or combinations thereof represent the same elements, and therefore their repeated descriptions can be omitted.

[0030] The described embodiments may have various modifications and may be implemented in different forms, and should not be construed as being limited to the illustrated embodiments herein. The use of "can", "may" or "may not" in the description of the embodiments corresponds to one or more embodiments of the present disclosure. The present disclosure encompasses all modifications, equivalents and alternatives within the scope of the ideas and techniques of the present disclosure. In addition, each of the features of the various embodiments of the present disclosure may be combined with each other in part or in whole, and various interlocks and drives are technically possible. Each embodiment may be implemented independently of one another or may be implemented together in conjunction.

[0031] It will be understood that when an element, layer, region, or component is referred to as being "formed on," "on," "connected to," or "(operably or communicatively) coupled to" another element, layer, region, or component, it may be formed directly on, directly on, directly connected to, or directly coupled to, or indirectly formed on, indirectly on, indirectly connected to, or indirectly coupled to, such that there may be one or more intervening elements, layers, regions, or components. This may collectively mean direct or indirect coupling or connection and integral or non-integrated coupling or connection. For example, when a layer, region, or component is referred to as being "electrically connected" or "electrically coupled" to another layer, region, or component, it may be directly electrically connected or coupled to, or there may be one or more intervening layers, regions, or components. One or more intermediate components may include switches, resistors, and / or capacitors, etc. In describing the embodiments, unless explicitly described as directly connected, the expression of connection indicates electrical connection, and "directly connected / directly coupled" or "directly on..." refers to one component being directly connected or coupled to another component, or being on another component, without intermediate components.

[0032] In this specification, when a portion of a layer, film, zone, plate, etc. is formed on another portion, the formation direction is not limited to the upper direction, but includes forming the portion on the side surface or in the lower direction. On the contrary, when a portion of a layer, film, zone, plate, etc. is formed "under" another portion, this includes not only the case where the portion is "directly below" the other portion, but also the case where there is another portion between the portion and the other portion. Other expressions describing the relationship between components such as "between...", "immediately between...", or "adjacent to..." and "directly adjacent to..." can be similarly interpreted. It will be understood that when an element or layer is referred to as "between" two elements or layers, it can be the only element or layer between the two elements or layers, or one or more intermediate elements or layers may also be present.

[0033] For the purposes of this disclosure, expressions such as "at least one of..." or "any one of..." or "one or more of...", when following a list of elements, modify the entire list of elements without modifying the individual elements of the list. For example, "at least one of X, Y, and Z," and "at least one selected from the group consisting of X, Y, and Z" may be interpreted as only X, only Y, only Z, any combination of two or more of X, Y, and Z, such as XYZ, XY, YZ, and XZ, or any variation thereof. Similarly, expressions such as "at least one of A and B" may include A, B, or A and B. As used herein, "or" generally means "and / or," and the term "and / or" includes any and all combinations of one or more of the associated listed items. For example, expressions such as "A and / or B" may include A, B, or A and B. Similarly, expressions such as "at least one of...", "a plurality of...", "one of...", and other prepositional phrases, when preceding / following a list of elements, modify the entire list of elements without modifying the individual elements of the list.

[0034] It will be understood that, although the terms "first", "second", "third", etc. can be used in this article to describe various elements, components, regions, layers and / or segments, these elements, components, regions, layers and / or segments should not be limited by these terms. These terms do not correspond to a specific order, position or priority, and are only used to distinguish an element, member, component, region, area, layer, segment or part from another element, member, component, region, area, layer, segment or part. Therefore, the first element, component, region, layer or segment described below can be referred to as the second element, component, region, layer or segment without departing from the spirit and scope of the present disclosure. Describing an element as a "first" element may not require or imply the presence of a second element or other elements. The terms "first", "second", etc. can also be used in this article to distinguish different categories or groups of elements. For simplicity, the terms "first", "second", etc. can respectively represent "first category (or first group)", "second category (or second group)", etc.

[0035] The terms used herein are only used for the purpose of describing the embodiments, and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form "one" is intended to also include the plural form, and the plural form is also intended to include the singular form. It will be further understood that when the terms "including", "having", "comprising" and variations thereof are used in this specification, the existence of the features, wholes, steps, operations, elements and / or parts stated is indicated, but the existence or addition of one or more other features, wholes, steps, operations, elements, parts and / or their groups is not excluded.

[0036] When one or more embodiments can be implemented differently, a specific process order can be performed differently from the order described. For example, two processes described successively can be performed substantially simultaneously or in an order opposite to the order described.

[0037] As used herein, the terms "substantially," "approximately," "approximately," and similar terms are used as approximate terms rather than as terms of degree, and are intended to illustrate the inherent deviations of measured or calculated values ​​that will be recognized by those of ordinary skill in the art. For example, "substantially" may include a range of + / -5% of the corresponding value. Taking into account the measurement in question and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system), "approximately" or "approximately" as used herein include the stated value and mean within an acceptable deviation range of the particular value as determined by those of ordinary skill in the art. For example, "approximately" may mean within one or more standard deviations, or within ±30%, ±20%, ±10%, ±5% of the stated value. In addition, when describing embodiments of the present disclosure, the use of "may" refers to "one or more embodiments of the present disclosure."

[0038] In some embodiments, known structures and devices related to one or more functional blocks (e.g., block diagrams), units and / or modules may be described in the accompanying drawings to avoid unnecessary blurring of various embodiments. It will be understood by those skilled in the art that such blocks, units and / or modules are physically implemented by logic circuits, individual components, microprocessors, hard-wired circuits, memory elements, line connections and other electronic circuits. This can be formed using semiconductor-based manufacturing techniques or other manufacturing techniques. Blocks, units and / or modules implemented by microprocessors or other similar hardware can be programmed and controlled using software to perform various functions discussed herein, and can be optionally driven by firmware and / or software. Each block, unit and / or module can be implemented by a combination of dedicated hardware or dedicated hardware that performs some functions and a processor (e.g., one or more programmed microprocessors and related circuits) that performs functions different from the functions of the dedicated hardware. In some embodiments, blocks, units and / or modules can be physically separated into two or more interactive individual blocks, units and / or modules without departing from the scope of the present disclosure. In some embodiments, blocks, units and / or modules can be physically combined into more complex blocks, units and / or modules without departing from the scope of the present disclosure.

[0039] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It will be further understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and / or this specification, and should not be interpreted in an idealized or overly formal sense, unless so explicitly defined herein.

[0040] Figure 1 A battery pack according to an embodiment of the present disclosure is schematically illustrated.

[0041] Reference Figure 1 , a battery pack according to an embodiment of the present disclosure may include a battery module 110, a processor 150, a memory 160, a voltage measurer (e.g., a voltage measuring unit) 120, a current measurer (e.g., a current measuring unit) 130, and a temperature measurer (e.g., a temperature measuring unit) 140.

[0042] The battery module 110 may include a plurality of battery cells 111, and the battery cells 111 may be rechargeable secondary batteries. For example, the battery cells 111 may include at least one selected from nickel-cadmium batteries, lead-acid batteries, nickel metal hydride (NiMH) batteries, lithium-ion batteries, lithium polymer batteries, and the like.

[0043] The number and connection method of the battery cells 111 included in the battery module 110 may be determined based on the amount of power and voltage suitable for the battery pack. Figure 1 It is shown that the battery cells 111 included in the battery module 110 are connected in series to each other only for conceptual purposes, but the battery cells 111 may be connected in parallel to each other or in series and in parallel. Figure 1 It is shown that the battery pack includes one battery module 110 only for conceptual purposes, but the battery pack may include a plurality of battery modules 110 connected to each other in series, in parallel, or in series and in parallel. The battery module 110 may include only one battery cell 111 .

[0044] The battery module 110 may include a plurality of battery modules, each of which includes a plurality of battery cells 111. The battery pack may include a pair of pack terminals 101 and 102 to which an electric load or a charging device may be connected.

[0045] In this specification, a corresponding aspect of assembly defect diagnosis may be a battery pack or at least one battery module 110 included in the battery pack.

[0046] The battery pack according to an embodiment of the present disclosure may include one or more switches. The switch may be connected between the battery module 110 and one or more of the group terminals 101 and 102 (e.g., the group terminal 101). The switch may be controlled by the processor 150. In one or more embodiments, the battery pack may further include a battery protection circuit, a fuse, a current sensor, and the like.

[0047] The apparatus for diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure may include a processor 150 and a memory 160 .

[0048] The processor 150 may control the overall operation of the apparatus for diagnosing assembly defects of a battery pack. For example, the processor 150 may be implemented in a form for selectively including a processor, an application specific integrated circuit (ASIC), a chipset, a logic circuit, a register, a communication modem, and / or a data processing device to perform the above operations.

[0049] The processor 150 may perform arithmetic, logic, and / or input / output operations, and may execute, for example, a program code stored in the memory 160. The processor 150 may store data in the memory 160, or may load data stored in the memory 160.

[0050] The memory 160 may be a recording medium readable by the processor 150, and may include a permanent mass storage device such as a random access memory (RAM), a read-only memory (ROM), and a disk drive. The memory 160 may store an operating system and at least one program or application code. According to an embodiment of the present disclosure, the memory 160 may store program code or data. For example, the data may include a charge / discharge current, a terminal voltage, and / or a temperature of a battery.

[0051] The memory 160 may store a program code for estimating the state of charge (SOC) of the battery by using data generated by measuring at least one parameter of the battery module 110, and may store SOC-open circuit voltage (OCV) data. In one or more embodiments, the memory 160 may store a program code or data for estimating the state of health (SOH) of the battery by using data generated by measuring at least one parameter of the battery module 110. Herein, the SOH of the battery may indicate a degradation state of the battery.

[0052] For example, the at least one parameter of the battery module 110 may include components or variables such as a terminal voltage, a charge / discharge current, and / or an ambient temperature of the battery module 110 .

[0053] The apparatus for diagnosing assembly defects of a battery pack according to an embodiment of the present disclosure may further include a voltage measurer 120, a current measurer 130, and a temperature measurer 140 for measuring at least one parameter of the battery module 110. The apparatus for diagnosing assembly defects of a battery pack may further include a communication module for communicating with other devices such as an electronic control device of a vehicle and a controller of a charging device.

[0054] The voltage measurer 120 may be configured to measure the voltage of the battery module 110. For example, Figure 1 As shown in the configuration of , the voltage measurer 120 may be electrically connected to both ends of the battery module 110 and / or the battery cell 111. In one or more embodiments, the voltage measurer 120 may be electrically connected to the processor 150 to send and receive electrical signals. In one or more embodiments, the voltage measurer 120 may measure the voltages of both ends of the battery module 110 and / or the battery cell 111 at time intervals under the control of the processor 150, and may output a signal indicating the magnitude of the measured voltage to the processor 150. The processor 150 may determine the voltage of the battery module 110 and / or the battery cell 111 based on the signal output from the voltage measurer 120. For example, the voltage measurer 120 may be implemented by using a voltage measurement circuit.

[0055] In one or more embodiments, the current measurer 130 may be configured to measure the current of the battery. For example, the current measurer 130 may be electrically connected to a current sensor provided on the charge / discharge path of the battery module 110 and / or the battery cell 111. In one or more embodiments, the current measurer 130 may be electrically connected to the processor 150 to send and receive electrical signals. In one or more embodiments, the current measurer 130 may repeatedly measure the amplitude of the charging current or the discharging current of the battery module 110 and / or the battery cell 111 at time intervals under the control of the processor 150, and may output a signal indicating the amplitude of the measured current to the processor 150. At this time, the processor 150 may determine the amplitude of the current based on the signal output from the current measurer 130. For example, the current sensor may be implemented by using a Hall sensor or a sensing resistor.

[0056] The temperature measurer 140 may be configured to measure the temperature of the battery. Figure 1 As shown in the configuration of , the temperature measurer 140 may be connected to the battery module 110 and / or the battery cell 111 to measure the temperature of the secondary battery provided in the battery module 110 and / or the battery cell 111. In one or more embodiments, the temperature measurer 140 may be electrically connected to the processor 150 to send and receive electrical signals. In one or more embodiments, the temperature measurer 140 may repeatedly measure the temperature of the secondary battery at time intervals, and may output a signal indicating the amplitude of the measured temperature to the processor 150. At this time, the processor 150 may determine the temperature of the secondary battery based on the signal output from the temperature measurer 140. For example, the temperature measurer 140 may be implemented by using a thermocouple.

[0057] In one or more embodiments, the processor 150 may estimate the SOC of the battery module 110 by using at least one of the voltage measurement value, the current measurement value, and the temperature measurement value of the battery module 110 received from the voltage measurer 120, the current measurer 130, and the temperature measurer 140, respectively. Herein, the SOC may be calculated as a value corresponding to the remaining charge amount of the battery module 110 in the range of about 0% to about 100%. In one or more embodiments, the processor 150 may estimate the SOH of the battery module 110 by using at least one of the voltage measurement value, the current measurement value, and the temperature measurement value of the battery module 110 received from the voltage measurer 120, the current measurer 130, and / or the temperature measurer 140, respectively, and may estimate the SOC data of the battery module 110. Herein, the SOH may be calculated as a value corresponding to the remaining charge amount of the battery module 110 in the range of about 0% to about 100%.

[0058] According to aspects of the present disclosure, the processor 150 may estimate the SOC of the battery module 110 by integrating the charging current and the discharging current of the battery module 110. If charging or discharging of the battery module 110 starts, an initial value of the SOC of the battery module 110 may be determined by using the OCV of the battery module 110 that may have been measured before charging or discharging of the battery module 110 starts. In one or more embodiments, the processor 150 may include an SOC-OCV lookup table in which the SOC is defined for each OCV, and the SOC corresponding to the OCV of the battery module 110 may be mapped from the lookup table.

[0059] The processor 150 may estimate the SOC of the battery module 110 by using an extended Kalman filter. The extended Kalman filter refers to a mathematical algorithm for adaptively estimating the SOC of a secondary battery by using the voltage, current, and temperature of the secondary battery.

[0060] The SOC of the battery module 110 may also be determined by other known methods, which may be used to estimate the SOC by selectively utilizing the voltage, current, and temperature of the secondary battery, and which are different from the above-described current integration method or extended Kalman filter.

[0061] Figure 2 is a diagram for explaining a method of diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure.

[0062] Refer to Figure 1 and Figure 2 , a battery pack according to an embodiment of the present disclosure may include a battery module 110 and a battery control unit (BCU) 100. For example, Figure 2 As shown in , the BCU 100 may include a processor 150, a contactor, a fuse, and a shunt resistor. However, the present disclosure is not limited thereto, and the BCU 100 according to an embodiment of the present disclosure may further include a battery protection circuit, a voltage measurement circuit, a current measurement circuit, and / or a temperature measurement circuit, etc.

[0063] The battery module 110 according to an embodiment of the present disclosure may be provided in a battery pack, and may include a plurality of battery cells 111. The BCU 100 according to an embodiment of the present disclosure may be provided in a battery pack, and may control charging / discharging of the battery module 110.

[0064] The processor 150 according to an embodiment of the present disclosure may calculate an internal resistance value of the battery module 110. In one or more embodiments, the processor 150 may calculate an internal resistance value of the BCU 100. In one or more embodiments, the processor 150 may diagnose an assembly defect of the battery pack by comparing a first voltage value of the battery pack with a second voltage value of the battery pack, the second voltage value being a measured voltage value of the battery pack. Herein, the first voltage value may be calculated based on the internal resistance value of the battery module 110 and the internal resistance value of the BCU 100.

[0065] In one or more embodiments, the processor 150 may obtain an internal resistance value measured (eg, measured in advance) by using both ends of the battery module 110 as measurement points.

[0066] In one or more embodiments, the processor 150 can calculate the internal resistance value of the battery module 110 based on the change in the internal resistance value according to the battery degradation state, and the change in the internal resistance value according to the battery degradation state can be stored (for example, pre-stored) according to the model of the battery cell 111.

[0067] In one or more embodiments, the processor 150 may calculate the internal resistance value of the battery pack by adding the internal resistance value of the battery module 110 and the internal resistance value of the BCU 100 based on the current degradation state, the internal resistance value of the battery module 110 reflecting the amount of change in the internal resistance value according to the battery degradation state.

[0068] In one or more embodiments, the processor 150 may calculate the first voltage value by multiplying the internal resistance value of the battery pack by the value of the current flowing through the two ends of the battery pack. In one or more embodiments, the processor 150 may compare the amplitude of the first voltage value with the amplitude of the second voltage value, and the second voltage value may be obtained by measuring the voltage at the two ends of the battery pack. If the amplitude of the second voltage value is greater than the amplitude of the first voltage value, the processor 150 may diagnose that there is an assembly defect in the battery pack.

[0069] In one or more embodiments, the processor 150 may calculate the internal resistance value of the BCU 100 based on an internal resistance value that may be measured (eg, measured in advance) by using a measurement point (eg, preset measurement point) for each component assembled and provided in the BCU 100 .

[0070] The battery pack may be wired to other components by welding, bolting, or connecting during assembly, and therefore, it may be appropriate to diagnose an assembly defect of a wiring portion. The contact resistance of a contact portion during wiring may be expressed as an internal resistance. For example, Figure 2As shown in , 300 battery cells 111 may be provided in a battery module 110 or a battery rack. Herein, a battery rack may include a plurality of battery modules. In one or more embodiments, a battery module 110 including 300 battery cells 111 may be described, but the present disclosure is not limited thereto and may be described with a battery rack including a plurality of battery modules.

[0071] For example, if there are 300 battery cells 111 having a voltage of about 4V, if a charging current of about 300A flows, the sum of the battery cell voltages may be equivalent to about 1200V. In one or more embodiments, if the contact resistance 115 of the contact portion in which each battery cell 111 is assembled is about 0.1mΩ, the total contact resistance due to the 300 contact portions may be about 30mΩ, and the internal resistance value of the battery module 110 may be about 30mΩ. In some embodiments, the voltage measured at the positive input / output terminal 117 and the negative input / output terminal 119 at both ends of the battery module 110 may be about 1209V (e.g., 1209V=0.0001Ω×300×300A+1200V).

[0072] Assuming that the contact resistance 115 of a normal contact portion without an assembly defect is about 0.1 mΩ, in a normal battery pack, if a charging current of about 300 A flows, a voltage difference of about 9 V may occur in the battery module 110, but if an assembly defect occurs in the contact portion, a voltage difference greater than 9 V may occur. There is a possibility of fire in the contact portion with the assembly defect, and therefore, it may be appropriate to detect the assembly defect in advance.

[0073] If the battery is charged / discharged, there may be a difference between a voltage value calculated by adding all battery cell voltages and a voltage value measured for the battery module due to the internal resistance value. For example, by using measurement points (e.g., preset measurement points) for components of the battery module and the BCU provided in the battery pack, the internal resistance value of each component may be measured. In one or more embodiments, the internal resistance values ​​for components of the battery module and the BCU provided in the battery pack may be stored (e.g., pre-stored) in a memory.

[0074] For example, Figure 2As shown in , the measurement points (e.g., preset measurement points) according to an embodiment of the present disclosure may include the positive input / output terminal 117 and the negative input / output terminal 119 at each end of the battery module 110, the positive input / output terminal 101 and the negative input / output terminal 102 of the battery pack, the measurement point Rack V+ between the positive input / output terminal 117 of the battery module 110 and the contactor, the measurement point Rack P+ between the fuse and the positive input / output terminal 101 of the battery pack, and the measurement point Rack V- between the shunt resistor and the negative input / output terminal 102 of the battery pack, etc.

[0075] In one or more embodiments, in the method for diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure, the internal resistance value of each component can be measured by using a measurement point (e.g., a preset measurement point). In one or more embodiments, the assembly defect of each component can be detected by using a voltage value measured between measurement points (e.g., preset measurement points). For example, the assembly defect of the contactor can be detected by using the internal resistance value and voltage value measured between the measurement point Rack V+ and the measurement point Rack P+.

[0076] Figure 3 1 is a flowchart for explaining a method for diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure. The method for diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure may be performed by Figure 1 The processor 150 shown in FIG. 1 executes.

[0077] First, refer to Figure 3 , in operation S110 , the processor 150 may calculate an internal resistance value of a battery module 110 that is provided in a battery pack and includes a plurality of battery cells 111 .

[0078] In one or more embodiments, the processor 150 according to an embodiment of the present disclosure may obtain an internal resistance value measured (eg, measured in advance) by using both ends of the battery module 110 as measurement points.

[0079] In one or more embodiments, the processor 150 according to an embodiment of the present disclosure can calculate the internal resistance value of the battery module 110 based on the change in the internal resistance value according to the battery degradation state, and the change in the internal resistance value according to the battery degradation state is stored (for example, pre-stored) according to the model of the battery cell 111.

[0080] In operation S120 , the processor 150 may calculate an internal resistance value of the BCU 100 provided in the battery pack and configured to control charging / discharging of the battery module 110 .

[0081] The processor 150 according to an embodiment of the present disclosure may calculate an internal resistance value of the BCU 100 based on an internal resistance value measured (e.g., measured in advance) by using a measurement point (e.g., a preset measurement point) for one or more components (e.g., for each component) assembled and provided in the BCU 100.

[0082] In operation S130, the processor 150 may diagnose an assembly defect of the battery pack by comparing a first voltage value of the battery pack calculated based on an internal resistance value of the battery module 110 and an internal resistance value of the BCU 100 with a second voltage value of the battery pack, the first voltage value being a measured voltage value of the battery pack.

[0083] The processor 150 according to an embodiment of the present disclosure may calculate the internal resistance value of the battery pack by adding the internal resistance value of the battery module 110 and the internal resistance value of the BCU 100 based on the current degradation state, the internal resistance value of the battery module 110 reflecting the amount of change in the internal resistance value according to the battery degradation state.

[0084] In one or more embodiments, the processor 150 may calculate the first voltage value by multiplying the internal resistance value of the battery pack by the value of the current flowing through the two ends of the battery pack. In one or more embodiments, the processor 150 may compare the magnitude of the first voltage value with the magnitude of the second voltage value, and the second voltage value is obtained by measuring the voltage at the two ends of the battery pack.

[0085] In one or more embodiments, if the magnitude of the second voltage value is greater than the magnitude of the first voltage value, the processor 150 according to an embodiment of the present disclosure may diagnose that there is an assembly defect in the battery pack.

[0086] According to an embodiment of the present disclosure, an apparatus for diagnosing an assembly defect of a battery pack may diagnose an assembly defect of the battery pack by comparing a first voltage value of the battery pack with a second voltage value of the battery pack, the first voltage value being calculated based on an internal resistance value of the battery module 110 and an internal resistance value of the BCU 100, and the second voltage value being a measured voltage value of the battery pack.

[0087] For example, the first voltage value may be calculated as V 1 =|(Q1×(1+E)+Q2)×(AB)|. In one or more embodiments, the second voltage value may be calculated as V 2=ΔV(DC)=V(D)-V(C). Herein, Q1 may represent the internal resistance value of the battery module 110, Q2 may represent the internal resistance value of the BCU 100, A may represent the current applied to the battery pack, B may represent the initial current of the battery pack, V(C) may represent the voltage of the battery pack before the current is applied, V(D) may represent the voltage of the battery pack 2 seconds after the current is applied, and E may represent the change rate of the internal resistance value according to the battery degradation state. Herein, E is described in detail below.

[0088] In one or more embodiments, if the magnitude of the second voltage value is greater than the magnitude of the first voltage value, the apparatus for diagnosing assembly defects of a battery pack according to an embodiment of the present disclosure may diagnose that there is an assembly defect in the battery pack. 2 >V 1 , it can be diagnosed that there is an assembly defect in the battery pack, and if V 2 ≤V 1 , it can be diagnosed that the battery pack is normal, and there is no assembly defect detected.

[0089] The apparatus for diagnosing an assembly defect of a battery pack according to an embodiment of the present disclosure may calculate the internal resistance value of the battery module 110 based on the amount of change in the internal resistance value according to the battery degradation state, which is stored (e.g., pre-stored) according to the model of the battery cell 111. For example, referring to Figure 4 , a graph for explaining a change amount of an internal resistance value according to a battery degradation state according to an embodiment of the present disclosure is shown.

[0090] In order to accurately diagnose an assembly defect in the battery module 110, it may be appropriate to reflect an increase in the internal resistance value according to the degradation state of the battery cell 111. The rate of change of the internal resistance value according to the battery degradation state may vary for each model of the battery cell 111. In one or more embodiments, data on the rate of change of the internal resistance value according to the battery degradation state for each model of the battery cell 111 may be stored (e.g., pre-stored) in a memory.

[0091] For example, refer to Figure 4 , the change rate of the internal resistance value according to the battery charge / discharge cycle is shown for battery cell model 1 (MODEL 1) and battery cell model 2 (MODEL 2). For example, one battery cycle may represent a cycle in which the SOC is discharged from about 100% to about 0%. In one or more embodiments, as the battery cycle increases, the battery may deteriorate, and therefore, the degradation state of the battery may be estimated based on the battery cycle.

[0092] For example, refer to Figure 4, it is shown that, for battery cell model 2, the internal resistance value of the battery has increased to about 130% after about 1500 cycles. The increase rate of the internal resistance value according to the battery cycle is approximately linear, and thus can be predicted with a trend line.

[0093] In the present disclosure, the first voltage value may be calculated as V 1 =|(Q1×(1+E)+Q2)×(AB)|, and E may represent a rate of change of the internal resistance value according to the battery degradation state. In some embodiments, if the internal resistance value of the battery increases to about 130% after about 1500 cycles for battery cell model 2, the value of E may be about 0.3.

[0094] According to the present disclosure, by more accurately estimating the internal resistance value of a battery by applying the increase rate of the internal resistance value according to the degradation state of the battery, an assembly defect of a battery pack can be diagnosed more accurately.

[0095] The various embodiments described above are merely examples and do not have to be distinguished and implemented independently of each other. The embodiments described in this specification may be implemented in combination with each other.

[0096] The various embodiments described above can be implemented in the form of a computer program executable by various components on a computer, and such a computer program can be recorded on a computer-readable medium. At this point, the medium can store computer executable programs continuously, or can temporarily store computer executable programs for execution or downloading. In one or more embodiments, the medium can be any of various recording media and storage media in which single-chip or multi-chip hardware is combined, and the medium is not limited to the medium directly connected to the computer system, but can be distributed on a network. Examples of media can include magnetic media such as hard disks, floppy disks, and tapes that are constructed to store program instructions, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floppy disks, and ROMs, RAMs, and flash memories, etc. Other examples of media can include recording media and storage media managed by application stores that distribute applications or by websites and servers that supply or distribute other various types of software.

[0097] In this specification, the term "unit" or "module" may be a hardware component such as a processor or circuit and / or a software component executed by a hardware component such as a processor. For example, a "unit" or "module" may be implemented by components such as software components, object-oriented software components, class components and task components, processes, functions, properties, procedures, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays, and variables.

[0098] According to the present disclosure, a method, a computer program, and an apparatus for diagnosing assembly defects of a battery can be provided, which can effectively diagnose assembly defects in the process of diagnosing assembly defects of a battery pack. However, the scope of the present disclosure is not limited by this effect.

[0099] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for limiting purposes. The description of multiple aspects within the embodiments should generally be considered applicable to other similar aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present disclosure as defined by the claims and their functional equivalents to be included therein.

Claims

1. A method for diagnosing an assembly defect of a battery pack, the method comprising: Calculating an internal resistance value of a battery module including a battery cell in the battery pack; calculating an internal resistance value of a battery control unit in the battery pack and configured to control charging or discharging of the battery module; as well as A first voltage value of the battery pack is compared with a second voltage value of the battery pack, the first voltage value being calculated based on the internal resistance value of the battery module and the internal resistance value of the battery control unit, and the second voltage value being a measured voltage value of the battery pack.

2. The method of claim 1, wherein: The calculating of the internal resistance value of the battery module includes using both ends of the battery module as measurement points.

3. The method of claim 2, wherein: The calculation of the internal resistance value of the battery module is based on a change amount of the internal resistance value of the battery module corresponding to a battery degradation state, the change amount of the internal resistance value of the battery module corresponding to a battery cell model.

4. The method of claim 3, further comprising: calculating an internal resistance value of the battery pack by adding the internal resistance value of the battery module and the internal resistance value of the battery control unit based on a current degradation state, the internal resistance value of the battery module reflecting the amount of change in the internal resistance value according to the battery degradation state; calculating the first voltage value by multiplying the internal resistance value of the battery pack by the value of the current flowing through both ends of the battery pack; as well as The magnitude of the first voltage value is compared with the magnitude of the second voltage value obtained by measuring the voltage at the two ends of the battery pack.

5. The method of claim 4, further comprising: The magnitude of the second voltage value is determined to be greater than the magnitude of the first voltage value.

6. The method of claim 1, wherein: The calculation of the internal resistance value of the battery control unit is based on using measurement points for components in the battery control unit.

7. A computer-readable recording medium having stored thereon a computer program for executing the method of claim 1 by using a computing device.

8. A device for diagnosing assembly defects of a battery pack, the device comprising: a battery module in the battery pack and including battery cells; a battery control unit in the battery pack and configured to control charging or discharging of the battery module; as well as A processor is configured to calculate an internal resistance value of the battery module, calculate an internal resistance value of the battery control unit, and diagnose the assembly defect of the battery pack by comparing a first voltage value of the battery pack with a second voltage value of the battery pack, wherein the first voltage value is calculated based on the internal resistance value of the battery module and the internal resistance value of the battery control unit, and the second voltage value is a measured voltage value of the battery pack.

9. The device of claim 8, wherein: The processor is further configured to use both ends of the battery module as measurement points.

10. The device of claim 9, wherein: The processor is further configured to calculate the internal resistance value of the battery module based on a change amount of the internal resistance value of the battery module corresponding to a battery degradation state, the change amount of the internal resistance value of the battery module corresponding to a battery cell model.

11. The device of claim 10, wherein: The processor is further configured to: calculating an internal resistance value of the battery pack by adding the internal resistance value of the battery module and the internal resistance value of the battery control unit based on a current degradation state, the internal resistance value of the battery module reflecting the amount of change in the internal resistance value according to the battery degradation state; calculating the first voltage value by multiplying the internal resistance value of the battery pack by the value of the current flowing through both ends of the battery pack; as well as The magnitude of the first voltage value is compared with the magnitude of the second voltage value obtained by measuring the voltage at the two ends of the battery pack.

12. The device of claim 11, wherein: The processor is further configured to diagnose the presence of the assembly defect in the battery pack when the magnitude of the second voltage value is greater than the magnitude of the first voltage value.

13. The device of claim 8, wherein: The processor is further configured to calculate the internal resistance value of the battery control unit based on use of measurement points for components assembled and provided in the battery control unit.

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