Battery diagnostic device and method

Abstract

The battery diagnostic device according to the present invention includes: a profile acquisition unit that acquires a battery profile showing the correspondence between the voltage and capacity of a battery to be diagnosed when charged or discharged at a target C rate; a profile correction unit that generates a correction profile by correcting the battery profile based on an overvoltage profile showing the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at the target C rate, and generates an adjusted negative electrode profile that is adjusted to show the correspondence between the negative electrode capacity and negative electrode potential of the battery to be diagnosed using the correction profile; and a control unit that diagnoses the state of the battery based on the negative electrode start potential value extracted from the adjusted negative electrode profile.

Description

Technical Field

[0001] The present invention relates to a battery diagnosis apparatus and method, and more particularly, to a battery diagnosis apparatus and method for diagnosing the state of a battery capable of repeated charge and discharge.

[0002] [[ID=⑨]]This application claims priority based on Korean Patent Application No. 10-2023-0115870 filed on August 31, 2023, and all of the content disclosed in the specification and drawings of the application is incorporated into this application.

Background Art

[0003] Recently, the demand for portable electronic products such as notebook PCs (Personal Computers), digital cameras, and mobile phones has increased rapidly. As the development of electric vehicles, energy storage batteries, robots, satellites, etc. has become full-scale, research on high-performance batteries capable of repeated charge and discharge has been actively conducted.

[0004] Currently, commercially available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium batteries, etc. Among these, lithium batteries have the advantages of almost no memory effect compared to nickel-based batteries, free charge and discharge, a very low self-discharge rate, and a high energy density.

[0005] Regarding technologies for increasing the capacity and density of such batteries, many studies are underway, but technologies for increasing the lifespan and improving the safety of batteries are also important. In particular, in order to improve the safety of batteries, a technology for accurately diagnosing the current state of batteries is required.

[0006] Traditionally, battery status was diagnosed by analyzing a battery profile that showed the correspondence between battery capacity and voltage. For example, the battery's capacity and voltage were measured during the charging process, and the battery status was diagnosed by analyzing the battery profile that showed the correspondence between the measured capacity and voltage. In another example, it is also possible to diagnose the battery status based on the capacity and voltage measured during the battery's discharge process. Therefore, in order to accurately diagnose the current state of a battery, a battery profile that accurately reflects the current state of the battery is required.

[0007] However, existing technologies require slow charging and discharging at low currents of 0.05C (C-rate) to obtain accurate battery profiles, which results in time-consuming and expensive battery diagnostics and makes it difficult to accurately and quickly diagnose multiple batteries.

[0008] On the other hand, when charging and discharging the battery with a high current of 0.3C or higher to shorten the battery diagnostic time, the acquired battery profile includes overvoltage, and this overvoltage can cause the battery profile to fail to accurately reflect the current state of the battery.

[0009] When using a battery profile that includes overvoltage, the battery's condition cannot be accurately diagnosed. As a result, slow charging and discharging, which is time-consuming and costly, is used to diagnose the battery's condition. [Overview of the project] [Problems that the invention aims to solve]

[0010] This invention has been made in view of the above-mentioned problems, and aims to provide a battery diagnostic device and method that can diagnose the state of a battery while taking into account the overvoltage of the battery that occurs when charging and discharging using a high current.

[0011] Other objects and advantages of the present invention will be more clearly understood by the embodiments of the invention described below. Furthermore, it can be understood that the objects and advantages of the present invention can be realized by the components of the invention as set forth in the claims. [Means for solving the problem]

[0012] A battery diagnostic device according to one aspect of the present invention includes: a profile acquisition unit configured to acquire a battery profile showing the correspondence between the voltage and capacity of a battery to be diagnosed when charged or discharged at a predetermined target C-rate (C-rate); a profile correction unit configured to generate a corrected profile by correcting the battery profile based on an overvoltage profile showing the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at the target C-rate, and to generate an adjusted negative electrode profile that is adjusted to show the correspondence between the negative electrode capacity and negative electrode potential of the battery to be diagnosed using the corrected profile; and a control unit configured to extract a negative electrode start potential value from the adjusted negative electrode profile and diagnose the state of the battery to be diagnosed based on the negative electrode start potential value.

[0013] In one embodiment, the overvoltage profile may be a profile showing the voltage difference for each capacity between a first battery profile of the reference battery obtained when the reference battery is charged or discharged at a reference C rate and a second battery profile of the reference battery obtained when the reference battery is charged or discharged at a target C rate.

[0014] In one embodiment, the profile correction unit may be configured to generate the correction profile by calculating the voltage difference for each capacity between the battery profile and the overvoltage profile.

[0015] In one embodiment, the battery diagnostic device further includes an overvoltage profile showing the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at a C rate different from the target C rate, and a storage unit for storing the overvoltage profile, wherein the profile correction unit may be configured to select the overvoltage profile corresponding to the target C rate from the overvoltage profiles stored in the storage unit and generate the correction profile using the selected overvoltage profile.

[0016] In one embodiment, the profile correction unit may be configured to generate a comparative full-cell profile corresponding to the correction profile by adjusting and synthesizing a predetermined reference positive electrode profile and a reference negative electrode profile, and to provide the reference negative electrode profile adjusted to generate the comparative full-cell profile as the adjusted negative electrode profile.

[0017] In one embodiment, the control unit may be configured to diagnose the battery under diagnosis as being in an abnormal state if the negative electrode start potential value is not within a predetermined threshold range.

[0018] In one embodiment, the control unit may be configured to further extract one or more of the following from the adjusted negative electrode profile as diagnostic factors: the negative electrode termination potential value, the negative electrode change rate, and the negative electrode load amount, and to diagnose the state of the battery to be diagnosed based on the extracted diagnostic factors.

[0019] In one embodiment, the control unit may be configured to diagnose the battery under diagnosis as being in a normal state if the values ​​of a predetermined number or more of the extracted diagnostic factors are within their respective corresponding threshold ranges.

[0020] A battery pack according to another aspect of the present invention includes a battery diagnostic device according to any one embodiment of the above-described embodiments.

[0021] A battery manufacturing system according to another aspect of the present invention includes a battery diagnostic device according to any one of the above-described embodiments.

[0022] A motor vehicle according to another aspect of the present invention includes a battery diagnostic device according to any one of the above-described embodiments.

[0023] A manufacturing method according to another aspect of the present invention includes a profile acquisition step of acquiring a battery profile indicating a correspondence relationship between the voltage and capacity of a diagnostic target battery charged or discharged at a predetermined target C-rate, a correction profile generation step of generating a correction profile by correcting the battery profile based on an overvoltage profile indicating the overvoltage for each capacity of the reference battery when the reference battery is charged or discharged at the target C-rate, a profile adjustment step of generating an adjusted negative electrode profile adjusted to indicate a correspondence relationship between the negative electrode capacity and the negative electrode potential of the diagnostic target battery using the correction profile, a diagnostic factor extraction step of extracting the negative electrode start potential value of the negative electrode profile as a diagnostic factor for the diagnostic target battery, and a state diagnosis step of diagnosing the state of the diagnostic target battery based on the negative electrode start potential value.

Advantages of the Invention

[0024] The battery diagnostic device and method according to the present invention generate a correction profile obtained by removing overvoltage from a battery profile indicating the correspondence relationship between the capacity and voltage of a battery, and diagnose the state of the battery based on such a correction profile. Therefore, there is an advantage that it is not necessary to force the diagnostic target battery to be charged or discharged using a current at a low C-rate.

[0025] That is, according to the present invention, even when the battery is charged or discharged with a current at a C-rate higher than the normally used C-rate, the state of the battery can be accurately diagnosed. As a result, the time and cost required to diagnose the state of the battery can be reduced, and the diagnosis of a plurality of batteries can be performed accurately and quickly.

[0026] Also, the battery diagnosis apparatus and method according to the present invention extract diagnosis factors serving as diagnosis criteria for a plurality of batteries, determine a threshold range of values that the diagnosis factors of a normal battery can have based on the extracted diagnosis factors, and perform diagnosis through a simplified process of comparing the diagnosis factor values of the battery to be diagnosed with the threshold range, thereby further shortening the diagnosis time.

[0027] Also, the battery diagnosis apparatus and method according to the present invention extract negative electrode-related diagnosis factors from an adjusted negative electrode profile indicating the state of the negative electrode of the battery, and diagnose the battery based on the extracted diagnosis factors, thereby specifically diagnosing the state of the battery regarding the negative electrode.

[0028] The effects of the present invention are not limited to the above-described effects, and other effects of the present invention not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0029] The following drawings attached to this specification serve to further understand the technical idea of the present invention together with the detailed description of the invention to be described later, and the present invention should not be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0030] [Figure 1] It is a diagram schematically showing a battery diagnosis apparatus according to an embodiment of the present invention. [Figure 2] It is a diagram schematically showing an overvoltage profile according to an embodiment of the present invention. [Figure 3] It is a diagram schematically showing a battery profile according to an embodiment of the present invention. [Figure 4] It is a diagram schematically showing a correction profile according to an embodiment of the present invention. [Figure 5] It is a diagram schematically showing the distribution of diagnosis factors according to an embodiment of the present invention. [Figure 6]This figure shows the distribution of diagnostic factor values ​​extracted from multiple batteries. [Figure 7] This figure shows the distribution of diagnostic factor values ​​extracted from multiple batteries. [Figure 8] This figure shows the distribution of diagnostic factor values ​​extracted from multiple batteries. [Figure 9] This figure shows the distribution of diagnostic factor values ​​extracted from multiple batteries. [Figure 10] This figure shows the distribution of diagnostic factor values ​​extracted from multiple batteries. [Figure 11] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 12] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 13] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 14] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 15] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 16] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 17] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 18] This figure illustrates the process of adjusting the reference positive electrode profile and the reference negative electrode profile according to one embodiment of the present invention. [Figure 19] This figure shows an exemplary configuration of a battery pack according to another embodiment of the present invention. [Figure 20]This figure illustrates the battery manufacturing process of a battery manufacturing system according to yet another embodiment of the present invention. [Figure 21] This figure shows an exemplary configuration of an automobile according to yet another embodiment of the present invention. [Figure 22] This figure schematically illustrates a battery diagnostic method according to yet another embodiment of the present invention. [Modes for carrying out the invention]

[0031] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0032] Terms and words used in this specification and in the claims should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather in a manner appropriate to the technical idea of ​​the present invention, in accordance with the principle that inventors themselves may appropriately define the concepts of terms in order to best describe their invention.

[0033] Therefore, the embodiments and configurations shown in the drawings described herein represent only one of the most preferred embodiments of the present invention and do not represent the entirety of the technical concept of the invention. It should be understood that there are various equivalents and modifications that can be substituted for these at the time of filing this application.

[0034] In addition, when describing the present invention, if it is determined that a specific description of a related known configuration or function would unnecessarily obscure the gist of the present invention, such description will be omitted.

[0035] Furthermore, terms that include ordinal numbers, such as "first," "second," etc., are used to distinguish one of the various components from the rest, and such terms do not limit the components themselves.

[0036] Throughout the specification, when a part of it "includes" a certain component, unless otherwise specified, it means that other components are not excluded and may further include other components.

[0037] Furthermore, when a part of the specification is described as being "connected" to another part, this includes not only cases where it is "directly connected," but also cases where it is "indirectly connected" through other elements in between.

[0038] Figure 1 is a schematic diagram showing a battery diagnostic device 100 according to one embodiment of the present invention.

[0039] Referring to Figure 1, the battery diagnostic device 100 may include a profile acquisition unit 110, a profile correction unit 120, and a control unit 130.

[0040] The profile acquisition unit 110 is configured to acquire a battery profile showing the correspondence between the voltage and capacity of a battery to be diagnosed, which is charged or discharged at a predetermined target C-rate. For example, the profile acquisition unit 110 may be configured to acquire multiple battery profiles BP showing the correspondence between the voltage and capacity of each of multiple batteries.

[0041] Here, "battery" can mean a single, independent cell that has a negative terminal and a positive terminal and is physically separable. For example, a lithium-ion battery or a lithium polymer battery may be considered a battery. Alternatively, "battery" can mean a battery bank, battery module, or battery pack in which multiple cells are connected in series and / or parallel. For the sake of explanation, below, a battery will be described as a single, independent cell.

[0042] Specifically, a battery profile BP is a profile that shows the correspondence between the voltage V and capacity Q of a battery as it is charged from 0% to 100% State of Charge (SOC). Alternatively, a battery profile BP may show the correspondence between the voltage V and capacity Q as the battery is discharged from 100% to 0% SOC. For example, a battery profile BP may be generated based on the voltage and electrical capacity of the battery as measured while the battery is being charged or discharged at a predetermined current rate (C rate). Here, the C rate of the charging or discharging current may be kept constant while the battery profile BP is being generated. That is, once a C rate for charging and discharging is set, the set C rate may be kept constant until charging and discharging are completed.

[0043] For reference, 1C (C-rate) can refer to the current required to fully charge a completely discharged battery in one hour of charging, or the current required to completely discharge a fully charged battery in one hour of discharge. The higher the C-rate, the greater the current, and the lower the C-rate, the greater the current. For example, 2C can refer to the amount of current required to fully charge a completely discharged battery in 0.5 hours of charging, or the amount of current required to completely discharge a fully charged battery in 0.5 hours of discharge.

[0044] For example, the profile acquisition unit 110 can directly receive the battery profile BP from an external device. That is, the profile acquisition unit 110 can be connected to an external device by wire and / or wireless connection and acquire the battery profile BP by receiving the battery profile BP from the external device.

[0045] In another example, the profile acquisition unit 110 may receive battery information regarding the battery voltage V and capacity Q. The profile acquisition unit 110 may then generate a battery profile BP based on the received battery information. That is, the profile acquisition unit 110 may acquire the battery profile BP by directly generating the battery profile BP based on the battery information.

[0046] The profile acquisition unit 110 may be connected to the profile correction unit 120 in a communicative manner. For example, the profile acquisition unit 110 may be connected to the control unit 130 by wire and / or wirelessly. The profile acquisition unit 110 may transmit the acquired battery profile BP to the profile correction unit 120.

[0047] The profile correction unit 120 may be configured to generate multiple correction profiles CP by correcting multiple battery profiles BP based on a preset overvoltage profile OP.

[0048] For example, the profile correction unit 120 may be configured to generate a correction profile by correcting the battery profile based on an overvoltage profile that shows the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at the target C rate, and to generate an adjusted negative electrode profile that is adjusted to show the correspondence between the negative electrode capacity and the negative electrode potential of the battery to be diagnosed using the correction profile.

[0049] Here, the overvoltage profile OP is a profile that shows the correspondence between the capacity of a battery being charged or discharged at a predetermined C rate and the overvoltage. For example, the overvoltage profile OP is a profile that shows the voltage difference for each capacity between a first battery profile of a reference battery obtained when the reference battery is charged or discharged at a reference C rate and a second battery profile of the reference battery obtained when the reference battery is charged or discharged at the target C rate.

[0050] Generally, charging and discharging a battery with a current at a C-rate higher than the reference C-rate may result in overvoltage being included in the measured battery voltage. Therefore, the overvoltage profile OP can be obtained by calculating the voltage difference per capacities between a first battery profile BP1 of a reference battery charged or discharged with a current at the reference C-rate and a second battery profile BP2 of a reference battery charged or discharged with a current at the same C-rate as the target C-rate of the charging or discharging current of the battery under diagnosis.

[0051] For example, suppose the reference C rate is 0.05C and the target C rate is 0.3C. When the reference battery is charged (or discharged) at 0.05C, a first battery profile BP1 may be obtained. When the reference battery is charged (or discharged) at 0.3C, a second battery profile BP2 may be obtained. The difference between the voltage of the first battery profile BP1 and the voltage of the second battery profile BP2 corresponding to a specific capacity can be calculated as the overvoltage at that specific capacity. That is, once the voltage difference (overvoltage) for each capacity between the first battery profile BP1 and the second battery profile BP2 is calculated, an overvoltage profile OP showing the correspondence between capacity and overvoltage may be generated.

[0052] Figure 2 is a schematic diagram showing the overvoltage profile OP according to one embodiment of the present invention.

[0053] Specifically, Figure 2 shows the overvoltage profile OP generated during the discharge process of a reference battery from its starting capacity Qi to its ending capacity Qf. A first battery profile BP1 can be generated when the reference battery is discharged at a reference C rate from its starting capacity Qi to its ending capacity Qf. Then, a second battery profile BP2 can be generated when the reference battery is discharged at a target C rate from its starting capacity Qi to its ending capacity Qf. An overvoltage profile OP can be generated by calculating the voltage difference between the first battery profile BP1 and the second battery profile BP2 for each discharge capacity from the starting capacity Qi to the ending capacity Qf.

[0054] The profile correction unit 120 may be configured to generate multiple correction profiles CP by calculating the voltage difference for each capacity between each of the multiple battery profiles BP and the overvoltage profile OP.

[0055] Specifically, the profile correction unit 120 can remove the overvoltage profile OP from the battery profile BP. For example, the profile correction unit 120 can generate a corrected profile CP by calculating the difference between the voltage of the battery profile BP and the overvoltage of the overvoltage profile OP for the same capacity, for each capacity. That is, the corrected profile CP is the profile from which the overvoltage profile OP has been removed from the battery profile BP.

[0056] Figure 3 is a schematic diagram showing the battery profile BP according to one embodiment of the present invention. Figure 4 is a schematic diagram showing the correction profile CP according to one embodiment of the present invention.

[0057] Specifically, the battery profile BP in Figure 3 is the profile obtained when the battery under diagnosis is discharged at the target C rate from the starting capacity Qi to the ending capacity Qf.

[0058] Referring to Figures 2 to 4, the profile correction unit 120 can generate the correction profile CP in Figure 4 by removing the overvoltage profile OP in Figure 2 from the battery profile BP in Figure 3. Here, the target C rate corresponding to the battery profile BP in Figure 3 and the target C rate corresponding to the overvoltage profile OP in Figure 2 are the same. That is, the correction profile CP can be generated based on the battery profile BP and overvoltage profile OP for the same target C rate.

[0059] The profile correction unit 120 may be configured to generate adjusted positive and adjusted negative electrode profiles corresponding to each battery by adjusting a preset reference positive electrode profile and a reference negative electrode profile to correspond to a plurality of correction profiles CP, respectively.

[0060] A reference positive electrode profile is a profile that shows the correspondence between the capacity and voltage of a reference positive electrode cell, which is pre-configured to correspond to the positive electrode of a battery. For example, the reference positive electrode cell may be the positive electrode of a positive coin-type half-cell or a three-electrode cell.

[0061] Furthermore, the reference negative electrode profile is a profile that shows the correspondence between the capacity and voltage of a reference negative electrode cell that is pre-set to correspond to the negative electrode of a battery. For example, the reference negative electrode cell may be the negative electrode of a negative coin-type half-cell or a three-electrode cell.

[0062] For example, the profile correction unit 120 can adjust the reference positive electrode profile and the reference negative electrode profile to correspond to the correction profile CP. That is, the profile correction unit 120 can generate an adjusted positive electrode profile and an adjusted negative electrode profile by adjusting the reference positive electrode profile and the reference negative electrode profile.

[0063] Subsequently, the profile correction unit 120 can generate a comparative full cell profile from the adjusted positive electrode profile and the adjusted negative electrode profile. The profile correction unit 120 can repeatedly adjust the reference positive electrode profile and the reference negative electrode profile until the comparative full cell profile corresponds to the corrected profile CP.

[0064] For example, the profile correction unit 120 can generate multiple comparison full cell profiles by shifting the reference positive electrode profile and the reference negative electrode profile, or by performing capacitance scaling, and then identify the comparison full cell profile that minimizes the error with the correction profile CP among the multiple comparison full cell profiles. In this way, the adjusted positive electrode profile and adjusted negative electrode profile corresponding to the identified comparison full cell profile can be determined.

[0065] A specific embodiment in which the profile correction unit 120 adjusts the reference positive electrode profile and reference negative electrode profile to correspond to the correction profile CP, thereby determining the adjusted positive electrode profile and adjusted negative electrode profile of the battery to be diagnosed, will be described later with reference to Figures 15 to 22.

[0066] The control unit 130 may be configured to extract diagnostic factors that serve as the basis for diagnosis from at least one of the adjusted positive electrode profile and adjusted negative electrode profile of the battery to be diagnosed. For example, the control unit 130 may extract one or more of the following from the adjusted negative electrode profile as diagnostic factors: negative electrode start potential value, negative electrode end potential value, negative electrode change rate, positive electrode load amount, and NP ratio, and diagnose the state of the battery to be diagnosed based on the extracted diagnostic factors.

[0067] As will be described later, the control unit 130 can extract diagnostic factors related to the positive electrode from the adjusted positive electrode profile. The control unit 130 can also extract diagnostic factors related to the negative electrode from the adjusted negative electrode profile. Furthermore, the control unit 130 can consider the diagnostic factors related to the positive electrode and the diagnostic factors related to the negative electrode together and extract diagnostic factors related to both the positive and negative electrodes.

[0068] For example, the control unit 130 may extract multiple diagnostic factors corresponding to each of the multiple batteries based on the adjusted positive electrode profile and / or adjusted negative electrode profile corresponding to each of the multiple batteries. In this case, the control unit 130 may extract the same type of diagnostic factor for each battery.

[0069] The control unit 130 may be configured to diagnose the status of multiple batteries based on the extracted diagnostic factors.

[0070] Specifically, since multiple diagnostic factors can be represented as the same type of value, the control unit 130 can generate a distribution diagram showing the distribution of the diagnostic factor values ​​of the multiple diagnostic factors. Furthermore, based on the generated distribution diagram, the control unit 130 can determine the threshold range of values ​​that a normal battery's diagnostic factors may have.

[0071] As a result, the control unit 130 can further shorten the diagnostic time by performing the diagnosis through a simplified process of comparing the diagnostic factor values ​​of the battery to be diagnosed with the threshold range.

[0072] Figure 5 is a schematic diagram showing the distribution of diagnostic factors according to one embodiment of the present invention. Specifically, Figure 5 shows an embodiment in which the distribution of multiple diagnostic factors follows a normal distribution.

[0073] As shown in Figure 5, the control unit 130 uses a statistical analysis method to determine the threshold range TH of values ​​that a normal battery's diagnostic factors may have, compares the diagnostic factor values ​​of the battery under diagnosis with the threshold range TH, and can diagnose the state of the battery under diagnosis as normal or abnormal based on the comparison result.

[0074] For example, the control unit 130 may be configured to select diagnostic factors that fall outside the threshold range TH from among the multiple diagnostic factors, taking into consideration the distribution of multiple diagnostic factors, and to diagnose the battery state corresponding to the selected diagnostic factor as an abnormal state. Conversely, the control unit 130 may be configured to select diagnostic factors that fall within the threshold range TH from among the multiple diagnostic factors, and to diagnose the battery state corresponding to the selected diagnostic factor as a normal state.

[0075] For example, if the mean value of a diagnostic factor is m and the standard deviation is σ, the threshold range TH can be determined to be the range of m-2σ or greater and m+2σ or less. The control unit 130 can classify multiple diagnostic factors into diagnostic factors that belong to the threshold range TH and diagnostic factors that do not belong to the threshold range TH.

[0076] Subsequently, the control unit 130 may diagnose the battery state corresponding to a diagnostic factor belonging to the threshold range TH as a normal state, and diagnose the battery state corresponding to a diagnostic factor not belonging to the threshold range TH as an abnormal state.

[0077] In the above, for the sake of explanation, an embodiment of the threshold range TH set based on 2σ has been described. However, it should be noted that the threshold range TH is not limited to the range of m-2σ or greater and m+2σ or less.

[0078] As described above, after the threshold range TH of possible values ​​for the diagnostic factors of a normal battery has been determined, if a diagnosis is performed on a new battery, the control unit 130 can quickly diagnose the state of the new battery through a simplified process of comparing the diagnostic factor values ​​of the new battery with the threshold range T.

[0079] The battery diagnostic device 100 according to the present invention diagnoses the state of the battery based on a corrected profile CP from which overvoltages have been removed from the battery profile BP. This has the advantage that charging and discharging with a reference C-rate current is not forced in order to diagnose the state of the battery. In other words, even when the battery is charged and discharged with a C-rate current different from the reference C-rate, for example, with a C-rate current higher than the reference C-rate, the state of the battery can be diagnosed, and the state of the battery can be diagnosed quickly without constraints on charging and discharging conditions.

[0080] Furthermore, the battery diagnostic device 100 has the advantage of being able to quickly distinguish between normal and abnormal batteries by relatively comparing the states of multiple batteries based on the distribution of multiple diagnostic factors.

[0081] On the other hand, the control unit 130 included in the battery diagnostic device 100 may include a general-purpose processor or ASIC (application-specific integrated circuit) known in the industry to perform the various control logics performed in the present invention, and may further selectively include a chipset, logic circuits, registers, memory, communication modem, etc. Furthermore, if the control logic is embodied as software, the control unit 130 may be embodied by a collection of program modules. In this case, the program modules are stored in memory and can be executed by the control unit 130. The memory may be included in the control unit 130 or located outside the control unit 130 and connected to the control unit 130 by wire and / or wireless.

[0082] The battery diagnostic device 100 may further include a storage unit 140. The storage unit 140 may store data and programs necessary for each component of the battery diagnostic device 100 to operate and function, or data generated during the process of operation and functioning. The type of storage unit 140 is not particularly limited as long as it is a known information storage means capable of recording, erasing, updating, and reading data. As an example, the information storage means may selectively include RAM (random access memory), ROM (read-only memory), EEPROM (electrically erasable programmable read-only memory), flash memory (registered trademark), registers, etc. The storage unit 140 may also store program code that defines processes executable by the control unit 130.

[0083] For example, the storage unit 140 can store multiple battery profiles BP, overvoltage profiles OP, multiple correction profiles CP, a reference positive electrode profile, a reference negative electrode profile, a modified positive electrode profile, a modified negative electrode profile, and multiple diagnostic factor values.

[0084] In one embodiment, the storage unit 140 may store, along with the overvoltage profile OP, an overvoltage profile indicating the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at a C rate different from the target C rate.

[0085] That is, the storage unit 140 can store a plurality of overvoltage profiles OP corresponding to various C rates applied to the charging or discharging of the battery under diagnosis. For example, the plurality of overvoltage profiles OP may include a first overvoltage profile OP1 that can be used to correct a first battery profile acquired while the battery under diagnosis is being charged or discharged with a first C rate current, and a second overvoltage profile OP2 that can be used to correct a second battery profile acquired while the battery under diagnosis is being charged or discharged with a second C rate current.

[0086] Furthermore, overvoltage profiles OP for C rates that have not been experimentally obtained can be acquired and stored through interpolation or extrapolation of similar overvoltage profiles OP. For example, if an overvoltage profile OP corresponding to 1C and an overvoltage profile OP corresponding to 1.2C are stored in advance, an overvoltage profile OP corresponding to 1.1C can be acquired based on the difference between the two overvoltage profiles OP.

[0087] In this case, the profile correction unit 120 may be configured to select an overvoltage profile OP corresponding to the target C rate from among a plurality of pre-stored overvoltage profiles OP, and to generate the correction profile using the selected overvoltage profile.

[0088] Here, the target C rate is the C rate of the charging or discharging current of the battery being diagnosed. For example, if multiple battery profiles BP are obtained during the process of multiple batteries being charged at 0.3C, the target C rate will be 0.3C. The profile correction unit 120 may select an overvoltage profile OP corresponding to 0.3C from among multiple overvoltage profiles OP.

[0089] The profile correction unit 120 may be configured to generate multiple correction profiles CP using the selected overvoltage profile OP.

[0090] For example, the profile correction unit 120 can generate multiple correction profiles CP by calculating the difference between each of the multiple battery profiles BP and the selected overvoltage profile OP. That is, the profile correction unit 120 can obtain multiple correction profiles CP in which the overvoltage is commonly removed.

[0091] Since overvoltage is noise, a battery profile BP containing overvoltage may not accurately reflect the current state of the battery. Therefore, a battery management device according to one embodiment of the present invention can remove the overvoltage included in the battery profile BP using an overvoltage profile OP corresponding to the target C rate. In other words, the battery management device has the advantage of being able to more accurately diagnose the state of the battery based on a corrected profile CP from which the overvoltage has been removed.

[0092] In one embodiment, the storage unit 140 can pre-store a plurality of overvoltage profiles OPa corresponding to the C rate of the charging current (hereinafter referred to as charging overvoltage profiles OPa) and a plurality of overvoltage profiles OPb corresponding to the C rate of the discharge current (hereinafter referred to as discharge overvoltage profiles OPb). In this case, the plurality of charging overvoltage profiles OPa and the plurality of discharge overvoltage profiles OPb can be stored independently.

[0093] Generally, batteries exhibit hysteresis during charging and discharging, meaning that even at the same voltage, the charging capacity and discharging capacity can have different values. Therefore, to more accurately diagnose the battery's condition, it is desirable to store the overvoltage profile corresponding to the C-rate of the charging current and the overvoltage profile corresponding to the C-rate of the discharging current separately.

[0094] On the other hand, the control unit 130 can determine the charge / discharge process (charging process or discharging process) corresponding to the battery profile BP. For example, the control unit 130 can determine the charge / discharge process of the battery profile BP by comparing the magnitude of the starting capacity and the ending capacity. Then, based on the determined charge / discharge process and target C rate, the control unit 130 can select the corresponding overvoltage profile OP.

[0095] A battery diagnostic device 100 according to one embodiment of the present invention can more accurately diagnose the status of multiple batteries by selecting an overvoltage profile OP that takes into account the target C rate and the charge / discharge process.

[0096] On the other hand, the profile correction unit 120 generates a comparative full cell profile corresponding to the correction profile by adjusting and synthesizing a predetermined reference positive electrode profile and a reference negative electrode profile, and can provide the control unit 130 with the reference negative electrode profile adjusted to generate the comparative full cell profile as the adjusted negative electrode profile.

[0097] The following describes in detail the diagnostic factors that the control unit 130 may extract from the adjusted positive electrode profile and / or adjusted negative electrode profile.

[0098] The control unit 130 may be configured to extract at least one of the following as diagnostic factors: a positive electrode-related diagnostic factor based on the adjusted positive electrode profile, a negative electrode-related diagnostic factor based on the adjusted negative electrode profile, and a positive / negative electrode-related diagnostic factor based on both the adjusted positive electrode profile and the adjusted negative electrode profile.

[0099] Here, the adjusted positive electrode profile is the result of adjusting the reference positive electrode profile, and the adjusted negative electrode profile is the result of adjusting the reference negative electrode profile. As described above, the profile correction unit 120 can adjust the reference positive electrode profile and the reference negative electrode profile so that the comparison full cell profile generated based on the reference positive electrode profile and the reference negative electrode profile corresponds to the correction profile CP.

[0100] Positive electrode-related factors may include at least one of the following: positive electrode start potential, positive electrode end potential, positive electrode rate of change, and positive electrode load, based on the adjusted positive electrode profile of the battery.

[0101] The positive electrode start potential is the start potential of the adjusted positive electrode profile, and the positive electrode end potential is the end potential of the adjusted positive electrode profile. Specifically, the positive electrode start potential is the potential value of the positive electrode engagement start point pi of the adjusted positive electrode profile. The positive electrode end potential is the potential value of the positive electrode engagement end point pf of the adjusted positive electrode profile.

[0102] The positive electrode change rate ps can refer to the percentage change [%] of the adjusted positive electrode profile relative to the reference positive electrode profile. Specifically, the positive electrode change rate ps can be the contraction or expansion rate of the adjusted positive electrode profile relative to the reference positive electrode profile. For example, if the adjusted positive electrode profile is contracted by 10% from the reference positive electrode profile, the positive electrode change rate ps is 90%. Conversely, if the adjusted positive electrode profile is expanded by 10% from the reference positive electrode profile, the positive electrode change rate ps is 110%.

[0103] The positive electrode load amount refers to the amount of positive electrode active material coated on the positive electrode current collector. Since the adjusted positive electrode profile is a profile that shows the current state of the battery's positive electrode, the control unit 130 can calculate the positive electrode load amount based on the adjusted positive electrode profile.

[0104] For example, the control unit 130 can calculate the positive electrode load amount by considering the positive electrode change rate ps, a preset reference positive electrode capacity, and a preset reference area. Here, the reference positive electrode capacity may mean the capacity of a preset reference positive electrode cell. Also, the reference area may mean the area of ​​a preset reference positive electrode cell. Specifically, the control unit 130 can calculate the positive electrode load amount using the following formula 1.

[0105] [Mathematics 1] p_loading=(ps×Q rc ) / A pc …(Equation 1)

[0106] In the formula, p_loading represents the positive electrode load amount, and ps represents the positive electrode change rate. Q rc This indicates the reference positive electrode capacity, A pc This indicates the standard area.

[0107] Negative electrode-related diagnostic factors may include at least one of the following based on the adjusted negative electrode profile: negative electrode start potential, negative electrode end potential, negative electrode change rate ns, and negative electrode load.

[0108] The negative electrode start potential is the start potential of the adjusted negative electrode profile, and the negative electrode end potential is the end potential of the adjusted negative electrode profile. Specifically, the negative electrode start potential is the potential value at the negative electrode involvement start point ni of the adjusted negative electrode profile. The negative electrode end potential is the potential value at the negative electrode involvement end point nf of the adjusted negative electrode profile.

[0109] The negative electrode change rate ns can represent the percentage change [%] in the adjusted negative electrode profile relative to the reference negative electrode profile. Specifically, the negative electrode change rate ns can be the contraction or expansion rate of the adjusted negative electrode profile relative to the reference negative electrode profile. For example, if the adjusted negative electrode profile contracts by 10% from the reference negative electrode profile, the negative electrode change rate ns would be 90%. Conversely, if the adjusted negative electrode profile expands by 10% from the reference negative electrode profile, the negative electrode change rate ns would be 110%.

[0110] The negative electrode load amount refers to the amount of negative electrode active material coated on the negative electrode current collector. Since the adjusted negative electrode profile is a profile that shows the current state of the battery's negative electrode, the control unit 130 can calculate the negative electrode load amount based on the adjusted negative electrode profile. Specifically, the control unit 130 can calculate the negative electrode load amount considering the negative electrode change rate, a preset reference negative electrode capacity, and a preset reference area. Here, the reference negative electrode capacity may refer to the capacity of a preset reference negative electrode cell. The reference area may refer to the area of ​​a preset reference negative electrode cell. Specifically, the control unit 130 can calculate the negative electrode load amount based on the negative electrode change rate, reference negative electrode capacity, and reference area using Equation 2 below.

[0111] [Math 2] n_loading=(ns×Q ra ) / A pa …(Equation 2)

[0112] In the formula, n_loading represents the negative electrode load amount, ns represents the negative electrode change rate, and Q ra This indicates the reference negative electrode capacity, A pa This indicates the standard area.

[0113] Positive and negative electrode-related factors may include the NP ratio, which can be calculated based on the positive and negative electrode loads.

[0114] Specifically, the NP ratio refers to the ratio of the negative electrode capacitance to the positive electrode capacitance. For example, the control unit 130 can calculate the NP ratio using the following formula 3.

[0115] [Math 3] np ratio = n - loading / p - loading …(Equation 3)

[0116] In the formulas, np ratio is the NP ratio, p-loading is the positive electrode load amount according to Equation 1, and n-loading is the negative electrode load amount according to Equation 2.

[0117] The battery diagnostic device 100 can extract at least one of the following as a diagnostic factor: positive electrode start potential, positive electrode end potential, positive electrode change rate, positive electrode load amount, negative electrode start potential, negative electrode end potential, negative electrode change rate, and NP ratio. Based on the distribution of each extracted diagnostic factor, the battery diagnostic device 100 can diagnose the state of multiple batteries as normal or abnormal.

[0118] For example, a battery diagnostic device 100 according to one embodiment of the present invention may extract negative electrode-related diagnostic factors or positive / negative electrode-related diagnostic factors from the aforementioned adjusted negative electrode profile in order to diagnose the condition of the negative electrode, such as the manufacturing quality and capacity loss of the negative electrode among the electrodes of the battery, and perform a diagnosis based on the extracted diagnostic factors.

[0119] Figures 6 to 10 show the distribution of diagnostic factor values ​​extracted from multiple batteries.

[0120] Specifically, Figure 6 is a graph showing the distribution of negative electrode start potential values ​​extracted from multiple batteries. Figure 7 is a graph showing the distribution of negative electrode end potential values ​​extracted from multiple batteries. Figure 8 is a graph showing the distribution of negative electrode change rate values ​​extracted from multiple batteries. Figure 9 is a graph showing the distribution of negative electrode load values ​​extracted from multiple batteries. Figure 10 is a graph showing the distribution of NP ratio values ​​extracted from multiple batteries. As mentioned above, in Figures 6 to 10, if the mean value is m and the standard deviation is σ, we assume that the threshold range TH for normal diagnostic factor values ​​is determined to be m ± 2σ.

[0121] When specific types of diagnostic factors are extracted from multiple batteries, the control unit 130 can diagnose the state of the multiple batteries based on the distribution of the extracted diagnostic factors.

[0122] Specifically, the control unit 130 can extract diagnostic factors related to items of interest from a predetermined set of battery diagnostic items, and diagnose the state of the battery based on the extracted diagnostic factors. The items of interest can be selected by the user or a pre-set program, and the control unit 130 can be configured to acquire information about the selected items of interest.

[0123] For example, if the item of interest concerns the state of the negative electrode, the control unit 130 may extract negative electrode start potential values ​​from multiple adjusted negative electrode profiles for multiple batteries. The control unit 130 may then select negative electrode start potentials from the extracted values ​​that fall outside the threshold range TH. That is, as shown in Figure 6, the control unit 130 may select negative electrode start potentials that exceed the upper limit m+2σ of the threshold range TH or are below the lower limit m-2σ of the threshold range TH. The control unit 130 may then diagnose the state of the battery corresponding to the selected negative electrode start potential as abnormal. On the other hand, the control unit 130 may diagnose the state of the remaining batteries as normal.

[0124] Thus, the battery diagnostic device 100 according to one embodiment of the present invention can extract diagnostic factors related to diagnostic items of interest and diagnose the state of the battery based on the extracted diagnostic factors. As a result, the battery diagnostic device 100 can accurately diagnose the state of the battery based on a correction profile CP from which overvoltage has been removed, and it has the advantage of being able to diagnose the state of the battery for each subdivided diagnostic item.

[0125] The following describes in detail an embodiment in which the profile correction unit 120 adjusts the reference positive electrode profile and the reference negative electrode profile.

[0126] The profile correction unit 120 may be configured to generate a comparison full cell profile based on the reference positive electrode profile and the reference negative electrode profile.

[0127] Specifically, a comparative full-cell profile can be generated by the voltage difference for each capacitance between the reference positive electrode profile and the reference negative electrode profile. For example, suppose the voltage of the reference positive electrode profile corresponding to an arbitrary capacitance x is Vp and the voltage of the reference negative electrode profile is Vn. The voltage of the comparative full-cell profile corresponding to capacitance x can be calculated by "Vp - Vn". The profile correction unit 120 can generate a comparative full-cell profile by calculating the voltage difference between the reference positive electrode profile and the reference negative electrode profile for the total capacitance.

[0128] The profile correction unit 120 may be configured to generate an adjusted positive electrode profile and an adjusted negative electrode profile by adjusting the reference positive electrode profile and the reference negative electrode profile until the generated comparison full cell profile corresponds to the corrected profile CP.

[0129] Specifically, the profile correction unit 120 can calculate the error between the comparison full cell profile and the correction profile CP. The profile correction unit 120 can then adjust the reference positive electrode profile and the reference negative electrode profile until the error between the comparison full cell profile and the correction profile CP is minimized. Once the comparison full cell profile that minimizes the error with the correction profile CP is determined, the adjusted positive electrode profile and adjusted negative electrode profile that form the basis of the determined comparison full cell profile can be estimated as the positive electrode profile and negative electrode profile that represent the current state of the battery.

[0130] Current technology has the drawback that the positive and negative electrode profiles, which indicate the current state of the battery, cannot be obtained without disassembling the battery. Therefore, in this invention, the adjusted positive and adjusted negative electrode profiles, which form the basis of the comparative full cell profile determined through the adjustment process described above, are used as the positive and negative electrode profiles that reflect the current state of the battery.

[0131] In the following section, an embodiment in which the profile correction unit 120 adjusts the reference positive electrode profile and the reference negative electrode profile will be described in more detail with reference to Figures 11 to 18.

[0132] Figures 11 to 18 illustrate the process by which the reference positive electrode profile and reference negative electrode profile are adjusted according to one embodiment of the present invention. For the sake of explanation, the corrected profile CP according to one embodiment of the present invention will be described below as the measured full cell profile M.

[0133] Figure 11 is a graph illustrating an example of a reference positive electrode profile Rp and a reference negative electrode profile Rn. In the graph in Figure 15, the horizontal axis (X axis) represents capacitance (Ah), and the vertical axis (Y axis) represents voltage (V).

[0134] Figure 12 is a graph used to illustrate an example of the measured full cell profile M of the target battery. In the graph of Figure 12, the horizontal axis (X axis) represents capacity (Ah), and the vertical axis (Y axis) represents voltage (V).

[0135] The profile correction unit 120 may be configured to compare the measured full cell profile M with at least one comparative full cell profile. Here, the comparative full cell profile may be the result of combining the adjusted positive electrode profile and the adjusted negative electrode profile based on the reference positive electrode profile Rp and the reference negative electrode profile Rn, respectively, stored in the storage unit 140.

[0136] In other words, if the reference full cell profile R is the result of subtracting a portion of the reference negative electrode profile Rn from a portion of the reference positive electrode profile Rp, then the comparative full cell profile can be said to be the result of subtracting a portion of the adjusted negative electrode profile from a portion of the adjusted positive electrode profile.

[0137] The profile correction unit 120 can generate at least one comparative full cell profile by directly adjusting the reference positive electrode profile Rp and the reference negative electrode profile Rn. Alternatively, at least one comparative full cell profile may be pre-allocated and stored in the storage unit 140 based on the reference positive electrode profile Rp and the reference negative electrode profile Rn. In this case, the profile correction unit 120 can retrieve the comparative full cell profile from the storage unit 140.

[0138] The profile correction unit 120 can generate multiple comparative full-cell profiles from the reference positive electrode profile Rp and the reference negative electrode profile Rn by repeatedly performing an adjustment process in which the reference positive electrode profile Rp and the reference negative electrode profile Rn are each adjusted to various levels and then combined. These comparative full-cell profiles may be referred to as "adjusted reference full-cell profiles".

[0139] The profile correction unit 120 can identify a specific comparison full cell profile from among multiple comparison full cell profiles that minimizes the error with the measured full cell profile M.

[0140] Subsequently, the profile correction unit 120 may determine the adjusted positive electrode profile and adjusted negative electrode profile corresponding to the identified comparison full cell profile as the positive electrode profile and negative electrode profile indicating the current state of the battery. Hereinafter, it should be noted that the positive electrode profile is the finally determined adjusted positive electrode profile, and the negative electrode profile is the finally determined adjusted negative electrode profile.

[0141] In this regard, various known methods available at the time of filing of the present invention can be used to determine the error between two profiles, each of which can be represented by a two-dimensional coordinate system. For example, the integral of the absolute value over the region between the two profiles or the root mean square error (RMSE) can be used as the error between the two profiles.

[0142] According to this configuration of the present invention, various state information about the battery can be obtained based on the finally determined positive electrode profile and negative electrode profile. The finally determined positive electrode profile and negative electrode profile correspond to the comparative full cell profile that most closely approximates the measured full cell profile. In other words, the comparative full cell profile generated by combining the finally determined positive electrode profile and negative electrode profile can be said to have almost identical shape and other characteristics to the measured full cell profile M.

[0143] Therefore, according to the present invention, the positive electrode profile and negative electrode profile of a battery can be obtained without disassembling the battery.

[0144] If the battery is new, its positive and negative electrode profiles can be analyzed to diagnose whether or not a defect has occurred in the battery, and if so, what type of defect it is.

[0145] Furthermore, if the battery is already in use, the degree of degradation in each degradation category can be determined from the battery's positive and negative electrode profiles.

[0146] Furthermore, according to the present invention, the positive electrode profile and negative electrode profile of the battery can be obtained by a simple process. The present invention can be implemented even if only one reference positive electrode profile Rp and one reference negative electrode profile Rn are stored in the storage unit 140. That is, it is not necessary for multiple reference positive electrode profiles Rp and / or multiple reference negative electrode profiles Rn to be stored in the storage unit 140. Therefore, the storage capacity of the storage unit 140 does not need to be high, and it is not necessary to perform many preliminary tests required to secure multiple reference positive electrode profiles Rp and / or multiple reference negative electrode profiles Rn.

[0147] Figures 13 to 15 illustrate an example of the process for generating a comparative full-cell profile used for comparison with a measured full-cell profile M according to one embodiment of the present invention.

[0148] The process for generating a comparative full-cell profile, as described with reference to Figures 13 to 15, is performed in the following order: a first process (see Figure 17) in which four points (positive electrode involvement start point, positive electrode involvement end point, negative electrode involvement start point, and negative electrode involvement end point) are set to correspond to the voltage range of interest; a second process (see Figure 18) in which a profile shift is performed; and a third process (see Figure 19) in which capacitance scaling is performed. That is, the process for generating a comparative full-cell profile according to one embodiment of the present invention includes the first to third processes.

[0149] First, referring to Figure 13, the reference positive electrode profile Rp and the reference negative electrode profile Rn are the same as those shown in Figure 11.

[0150] The profile correction unit 120 determines the positive electrode involvement start point pi, positive electrode involvement end point pf, negative electrode involvement start point ni, and negative electrode involvement end point nf in the reference positive electrode profile Rp and reference negative electrode profile Rn.

[0151] Either the positive electrode involvement start point pi or the negative electrode involvement start point ni depends on the other.

[0152] For example, the profile correction unit 120 may divide the positive electrode voltage range from the start point to the end point (or second set voltage) of the reference positive electrode profile Rp into a plurality of minute voltage intervals, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the positive electrode involvement start point pi. Each minute voltage interval may have a predetermined size (e.g., 0.01V). Subsequently, the profile correction unit 120 may set a point in the reference negative electrode profile Rn that is smaller by a first set voltage (e.g., 3V) than the positive electrode involvement start point pi as the negative electrode involvement start point ni.

[0153] In another example, the profile correction unit 120 may divide the negative voltage range of the reference negative electrode profile Rn from the start point to the end point into a plurality of minute voltage intervals of a predetermined size, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the negative electrode involvement start point ni. Subsequently, the profile correction unit 120 may search for a point in the reference positive electrode profile Rp that is greater than the negative electrode involvement start point ni by a first set voltage, and set the searched point as the positive electrode involvement start point pi.

[0154] Furthermore, either the positive electrode-involved termination point pf or the negative electrode-involved termination point nf depends on the other.

[0155] For example, the profile correction unit 120 may divide the voltage range from the second set voltage to the end point of the reference positive electrode profile Rp into a plurality of minute voltage intervals of a predetermined size, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the positive electrode involvement termination point pf. Subsequently, the profile correction unit 120 may set a point in the reference negative electrode profile Rn that is smaller than the positive electrode involvement termination point pf by the second set voltage (e.g., 4V) as the negative electrode involvement termination point nf.

[0156] In another example, the profile correction unit 120 may divide the negative voltage range of the reference negative electrode profile Rn from the start point to the end point into a plurality of minute voltage intervals of a predetermined size, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the negative electrode involvement termination point nf. Subsequently, the profile correction unit 120 may search for a point in the reference positive electrode profile Rp that is greater than the negative electrode involvement termination point nf by a second set voltage, and set the searched point as the positive electrode involvement termination point pf.

[0157] Thus, once the determination of the positive electrode involvement start point pi, positive electrode involvement end point pf, negative electrode involvement start point ni, and negative electrode involvement end point nf is complete, the profile correction unit 120 shifts at least one of the reference positive electrode profile Rp and reference negative electrode profile Rn to the left or right along the horizontal axis (capacitance axis).

[0158] Referring to Figure 14, the profile correction unit 120 can shift the reference positive electrode profile Rp and / or reference negative electrode profile Rn so that the capacitance values ​​of the positive electrode involvement start point pi and the negative electrode involvement start point ni match.

[0159] Alternatively, the profile correction unit 120 may shift the reference positive electrode profile Rp and / or reference negative electrode profile Rn so that the voltages at the positive electrode termination point pf and the negative electrode termination point nf match.

[0160] Figure 14 shows that the adjusted reference positive electrode profile Rp' is generated by shifting only the reference positive electrode profile Rp to the left, resulting in a situation where the voltage at the positive electrode engagement start point pi' matches the voltage at the negative electrode engagement start point ni. The adjusted reference positive electrode profile Rp' is the result of applying an adjustment to the reference positive electrode profile Rp that shifts it to the left by the voltage difference between the positive electrode engagement start point pi and the negative electrode engagement start point ni. Therefore, the two points pi and pi' differ only in capacitance value, but have the same voltage. The two points pf and pf' differ only in capacitance value, but have the same voltage.

[0161] Once adjusted profiles Rp' and Rn are secured, obtained by shifting at least one of the reference positive electrode profile Rp and the reference negative electrode profile Rn, the profile correction unit 120 scales at least one of the capacitance ranges of the adjusted profiles Rp' and Rn.

[0162] Referring to Figure 14, the profile correction unit 120 further performs an adjustment process to reduce or expand at least one of the adjusted reference positive electrode profile Rp' and reference negative electrode profile Rn along the horizontal axis (capacitance axis).

[0163] Referring to Figure 15, the profile correction unit 120 can generate an adjusted reference positive electrode profile Rp'' by shrinking or expanding the adjusted reference positive electrode profile Rp' so that the size of the capacitance range between two points pi' and pf' in the adjusted reference positive electrode profile Rp' matches the size of the capacitance range of the measured full cell profile M. In this case, one of the two points pi' and pf' can be fixed. As a result, the capacitance difference between the two points pi' and pf'' in the adjusted reference positive electrode profile Rp'' matches the size of the capacitance range of the measured full cell profile M.

[0164] Furthermore, the profile correction unit 120 can generate an adjusted reference negative electrode profile Rn' by reducing or expanding the reference negative electrode profile Rn so that the size of the capacitance range between the two points ni and nf in the reference negative electrode profile Rn matches the size of the capacitance range of the measured full cell profile M. In this case, one of the two points ni and nf can be fixed. As a result, the capacitance difference between the two points ni and nf' in the adjusted reference negative electrode profile Rn' will match the capacitance range of the measured full cell profile M.

[0165] In Figure 15, the adjusted reference positive electrode profile Rp'' is the result of reducing the adjusted reference positive electrode profile Rp' shown in Figure 14, and the adjusted reference negative electrode profile Rn' is the result of expanding the reference negative electrode profile Rn shown in Figure 14.

[0166] The positive electrode involvement endpoint pf in the adjusted reference positive electrode profile Rp'' corresponds to the positive electrode involvement endpoint pf in the adjusted reference positive electrode profile Rp'. The negative electrode involvement endpoint nf' in the adjusted reference negative electrode profile Rn' corresponds to the negative electrode involvement endpoint nf in the reference negative electrode profile Rn.

[0167] The capacitance difference between the cathode involvement start point pi' and the cathode involvement end point pf'' of the adjusted reference cathode profile Rp'' corresponds to the size of the capacitance range of the measured full cell profile M. Similarly, the capacitance difference between the anode involvement start point ni and the anode involvement end point nf'' of the adjusted reference cathode profile Rn' corresponds to the size of the capacitance range of the measured full cell profile M.

[0168] Furthermore, the capacitance difference between two points pi' and pf'' in the adjusted reference positive electrode profile Rp'' matches the capacitance difference between two points ni and nf' in the adjusted reference negative electrode profile Rn'. The profile correction unit 120 can generate a comparative full cell profile S by subtracting the portion between two points ni and nf' in the adjusted reference negative electrode profile Rn' from the portion between the two points pi' and pf'' in the adjusted reference positive electrode profile Rp''.

[0169] The profile correction unit 120 can calculate the error (profile error) between the comparison full cell profile S and the measured full cell profile M.

[0170] When the error between the comparative full cell profile S and the measured full cell profile M is minimized, the adjusted reference positive electrode profile Rp'' corresponding to the comparative full cell profile S may be determined as the adjusted positive electrode profile, and the adjusted reference negative electrode profile Rn' may be determined as the adjusted negative electrode profile.

[0171] The profile correction unit 120 can map at least two of the following to each other and record them in the storage unit 140: the adjusted reference positive electrode profile Rp'', the adjusted reference negative electrode profile Rn', the positive electrode involvement start point pi', the positive electrode involvement end point pf'', the negative electrode involvement start point ni, the negative electrode involvement end point nf', the first scale factor, the second scale factor, the comparison full cell profile S, and the profile error. Here, the first scale factor may represent the ratio of the capacitance difference between two points pi' and pf'' to the capacitance difference between two points pi0 and pf0. The second scale factor may represent the ratio of the capacitance difference between two points ni and nf' to the capacitance difference between two points ni0 and nf0.

[0172] Furthermore, the profile correction unit 120 can calculate the positive electrode change rate ps of the adjusted reference positive electrode profile Rp'' relative to the reference positive electrode profile Rp. The profile correction unit 120 can also calculate the negative electrode change rate ns of the adjusted reference positive electrode profile Rn' relative to the reference negative electrode profile Rn. In this case, the profile correction unit 120 can determine the first scale factor as the positive electrode change rate ps and the second scale factor as the negative electrode change rate ns.

[0173] On the other hand, as mentioned above, when the positive electrode voltage range of the reference positive electrode profile Rp is divided into multiple minute voltage intervals, the boundary point between two adjacent minute voltage intervals can be set as the positive electrode involvement start point pi.

[0174] For example, if the positive electrode voltage range of the reference positive electrode profile Rp is divided into 100 minute voltage ranges, there may be 100 boundary points that can be set as the positive electrode involvement start point pi. Also, if the voltage range of the reference positive electrode profile Rp above the second set voltage is divided into 40 minute voltage ranges, there may be 40 boundary points that can be set as the positive electrode involvement end point pf. In this case, up to 4,000 distinct comparison full cell profiles can be generated.

[0175] Of course, it will be easily understood by those skilled in the art that the number of comparative full-cell profiles that can be generated increases as the size of the minute voltage interval decreases, and conversely, the number of comparative full-cell profiles that can be generated decreases as the size of the minute voltage interval increases.

[0176] The profile correction unit 120 identifies the minimum profile error among the multiple comparison full cell profiles generated as described above, and then can obtain information mapped to the minimum profile error (for example, at least one of the following: positive electrode involvement start point pi, positive electrode involvement end point pf, negative electrode involvement start point ni, negative electrode involvement end point nf, positive electrode change rate ps, negative electrode change rate ns, and the capacitance ratio between the positive and negative electrodes) from the storage unit 140.

[0177] Figures 16-18 illustrate another example of the process of generating a comparative full-cell profile used for comparison with the measured full-cell profile M by one embodiment of the present invention.

[0178] For reference, the embodiments shown in Figures 16 to 18 are independent of the embodiments shown in Figures 13 to 15. Therefore, terms and reference numerals common to the embodiments shown in Figures 13 to 15 and Figures 16 to 18 are limited to each respective embodiment.

[0179] The process for generating a comparative full-cell profile, as described with reference to Figures 16 to 18, is carried out in the following order: a fourth process (see Figure 16) for performing capacity scaling, a fifth process (see Figure 17) for setting four points (positive electrode involvement start point, positive electrode involvement end point, negative electrode involvement start point, negative electrode involvement end point), and a sixth process (see Figure 18) for performing profile shifting. That is, the process for generating a comparative full-cell profile according to other embodiments of the present invention includes processes 4 to 6.

[0180] First, referring to Figure 16, the reference positive electrode profile Rp and the reference negative electrode profile Rn are identical to those shown in Figure 11.

[0181] The profile correction unit 120 applies the first scale factor and the second scale factor selected from the scaling numerical range to the reference positive electrode profile Rp and the reference negative electrode profile Rn, respectively, to generate the adjusted reference positive electrode profile Rp' and the adjusted reference negative electrode profile Rn'.

[0182] The scaling numerical range is predetermined or can vary depending on the ratio of the volume range size of the measured full-cell profile M to the volume range size of the reference full-cell profile R. For example, if values ​​with 0.1% intervals (i.e., 90%, 90.1%, 90.2%, ..., 98.9%, 99%) are selectable as the first and second scale factors within the scaling numerical range (e.g., 90-99%), then 91 values ​​can be selected as the first and second scale factors, respectively. In this case, 91 × 91 = 8,281 adjustment levels (combinations of the first and second scale factors) can generate up to 8,281 adjusted profile pairs. An adjusted profile pair means a combination of an adjusted reference positive electrode profile and an adjusted reference negative electrode profile.

[0183] The adjusted reference positive electrode profile Rp' and adjusted reference negative electrode profile Rn' shown in Figure 16 represent the results of applying a first scale factor and a second scale factor of less than 100%, respectively, to the reference positive electrode profile Rp and the reference negative electrode profile Rn.

[0184] Because the first and second scale factors are less than 100%, the adjusted reference positive electrode profile Rp' is the reference positive electrode profile Rp scaled down along the horizontal axis, and similarly, the adjusted reference negative electrode profile Rn' is the reference negative electrode profile Rn scaled down along the horizontal axis. For the sake of understanding, the starting points of the positive electrode profile Rp and the reference negative electrode profile Rn are fixed, and only the remaining portions are shown scaled down to the left along the horizontal axis.

[0185] Referring to Figure 17, the profile correction unit 120 determines the positive electrode involvement start point pi', positive electrode involvement end point pf', negative electrode involvement start point ni', and negative electrode involvement end point nf' in the adjusted reference positive electrode profile Rp' and the adjusted reference negative electrode profile Rn'.

[0186] Either the positive electrode involvement start point pi' or the negative electrode involvement start point ni' may depend on the other. Similarly, either the positive electrode involvement end point pf' or the negative electrode involvement end point nf' may depend on the other. Furthermore, either the positive electrode involvement start point pi' or the positive electrode involvement end point pf' may be set based on the other.

[0187] That is, once one of the positive electrode involvement start point pi', positive electrode involvement end point pf', negative electrode involvement start point ni', and negative electrode involvement end point nf' is set, the remaining three points can be automatically set by the first set voltage, the second set voltage, and / or the size of the capacitance range of the measured full cell profile M (e.g., the charge capacity from SOC 0 to 100%).

[0188] For example, the profile correction unit 120 may divide the positive electrode voltage range from the start point to the end point (or second set voltage) of the adjusted reference positive electrode profile Rp' into a plurality of minute voltage intervals, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the positive electrode involvement start point pi'. Subsequently, the profile correction unit 120 may set a point in the adjusted reference negative electrode profile Rn that is smaller by a first set voltage (e.g., 3V) than the positive electrode involvement start point pi' as the negative electrode involvement start point ni'.

[0189] In another example, the profile correction unit 120 may divide the negative voltage range from the start point to the end point of the adjusted reference negative electrode profile Rn' into a plurality of minute voltage intervals of a predetermined size, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the negative electrode involvement start point ni'. Subsequently, the profile correction unit 120 may search for a point in the reference positive electrode profile Rp that is greater than the negative electrode involvement start point ni' by a first set voltage, and set the searched point as the positive electrode involvement start point pi'.

[0190] In yet another example, the profile correction unit 120 may divide the voltage range from the second set voltage to the end point of the adjusted reference positive electrode profile Rp' into a plurality of minute voltage intervals of a predetermined size, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the positive electrode involvement end point pf'. Subsequently, the profile correction unit 120 may search for a point that is smaller than the positive electrode involvement end point pf' by the second set voltage (e.g., 4V) from the adjusted reference negative electrode profile Rn', and set the found point as the negative electrode involvement end point nf'.

[0191] In yet another example, the profile correction unit 120 may divide the negative voltage range from the start to the end point of the adjusted reference negative electrode profile Rn' into a plurality of minute voltage intervals of a predetermined size, and then set the boundary point of two adjacent minute voltage intervals among the plurality of minute voltage intervals as the negative electrode involvement termination point nf'. Subsequently, the profile correction unit 120 may search for a point in the adjusted reference positive electrode profile Rp' that is greater than the negative electrode involvement termination point nf' by a second set voltage, and set the found point as the positive electrode involvement termination point pf'.

[0192] Once one of the positive electrode involvement start point pi', positive electrode involvement end point pf', negative electrode involvement start point ni', and negative electrode involvement end point nf' is determined, the profile correction unit 120 may further determine the remaining three points based on the determined point.

[0193] For example, if the positive electrode involvement start point pi' is determined first, the profile correction unit 120 may set a point in the adjusted reference positive electrode profile Rp' that has a capacitance value larger by the size of the capacitance range of the measured full cell profile M than the capacitance value of the positive electrode involvement start point pi' as the positive electrode involvement end point pf'. Alternatively, the profile correction unit 120 may search for a point in the adjusted reference negative electrode profile Rn' that is lower by a first set voltage than the positive electrode involvement start point pi', and set the found point as the negative electrode involvement start point ni'. Furthermore, the profile correction unit 120 may set a point in the adjusted reference negative electrode profile Rn' that has a capacitance value larger by the size of the capacitance range of the measured full cell profile M than the capacitance value of the negative electrode involvement start point ni' as the negative electrode involvement end point nf'.

[0194] In another example, if the positive electrode involvement termination point pf' is determined first, the profile correction unit 120 may set a point in the adjusted reference positive electrode profile Rp' having a capacitance value smaller by the size of the capacitance range of the measured full cell profile M than the capacitance value of the positive electrode involvement termination point pf' as the positive electrode involvement start point pi'. Alternatively, the profile correction unit 120 may search for a point in the adjusted reference negative electrode profile Rn' that is lower by a second set voltage than the positive electrode involvement termination point pf', and set the found point as the negative electrode involvement termination point nf'. Furthermore, the profile correction unit 120 may set a point in the adjusted reference negative electrode profile Rn' having a capacitance value smaller by the size of the capacitance range of the measured full cell profile M than the capacitance value of the negative electrode involvement termination point nf' as the negative electrode involvement start point ni'.

[0195] In another example, once the negative electrode involvement start point ni' is determined, the profile correction unit 120 may set a point in the adjusted reference negative electrode profile Rn' having a capacitance value that is larger by the size of the capacitance range of the measured full cell profile M than the capacitance value of the negative electrode involvement start point ni' as the negative electrode involvement end point nf'. The profile correction unit 120 may also search for a point in the adjusted reference positive electrode profile Rp' that is higher by a first set voltage than the negative electrode involvement start point ni', and set the found point as the positive electrode involvement start point pi'. The profile correction unit 120 may also set a point in the adjusted reference positive electrode profile Rp' having a capacitance value that is larger by the size of the capacitance range of the measured full cell profile M than the capacitance value of the positive electrode involvement start point pi' as the positive electrode involvement end point pf'.

[0196] In another example, once the negative electrode involvement termination point nf' is determined, the profile correction unit 120 may set a point in the adjusted reference negative electrode profile Rn' having a capacitance value smaller by the size of the capacitance range of the measured full cell profile M than the capacitance value of the negative electrode involvement termination point nf' as the negative electrode involvement start point ni'. The profile correction unit 120 may also search for a point in the adjusted reference positive electrode profile Rp' that is higher by a second set voltage than the negative electrode involvement termination point nf', and set the found point as the positive electrode involvement termination point pf'. Furthermore, the profile correction unit 120 may set a point in the adjusted reference positive electrode profile Rp' having a capacitance value smaller by the size of the capacitance range of the measured full cell profile M than the capacitance value of the positive electrode involvement termination point pf' as the positive electrode involvement start point pi'.

[0197] Once the determination of the positive electrode involvement start point pi', positive electrode involvement end point pf', negative electrode involvement start point ni', and negative electrode involvement end point nf' is complete based on the pair of the first and second scale factors, the profile correction unit 120 may shift at least one of the adjusted reference positive electrode profile Rp' and adjusted reference negative electrode profile Rn' along the horizontal axis so that the capacitance values ​​of the positive electrode involvement start point pi' and negative electrode involvement start point ni' match, or so that the capacitance values ​​of the positive electrode involvement end point pf' and negative electrode involvement end point nf' match.

[0198] The adjusted reference negative electrode profile Rn'' shown in Figure 18 is obtained by shifting only the adjusted reference negative electrode profile Rn' shown in Figure 17 to the right. As a result, the capacitance values ​​at the positive electrode involvement start point pi' and the negative electrode involvement start point ni' match each other. In relation to this, the capacitance difference between the positive electrode involvement start point pi' and the positive electrode involvement end point pf' is the same as the capacitance difference between the negative electrode involvement start point ni' and the negative electrode involvement end point nf. Therefore, when the capacitance values ​​at the positive electrode involvement start point pi' and the negative electrode involvement start point ni'' match each other, the capacitance values ​​at the positive electrode involvement end point pf' and the negative electrode involvement end point nf'' also match each other.

[0199] Referring to Figure 18, the profile correction unit 120 can generate a comparative full cell profile U by subtracting the partial profile between two points pi' and pf' of the adjusted reference positive electrode profile Rp' from the partial profile between two points ni'' and nf'' of the adjusted reference negative electrode profile Rn''.

[0200] The profile correction unit 120 can calculate the error (profile error) between the comparison full cell profile U and the measured full cell profile M.

[0201] When the error between the comparative full cell profile U and the measured full cell profile M is minimized, the adjusted reference positive electrode profile Rp' corresponding to the comparative full cell profile U may be determined as the adjusted positive electrode profile, and the adjusted reference negative electrode profile Rn'' may be determined as the adjusted negative electrode profile.

[0202] The profile correction unit 120 can map at least two of the following to each other and record them in the storage unit 140: the adjusted reference positive electrode profile Rp', the adjusted reference negative electrode profile Rn'', the positive electrode involvement start point pi', the positive electrode involvement end point pf', the negative electrode involvement start point ni'', the negative electrode involvement end point nf'', the positive electrode change rate ps, the negative electrode change rate ns, the comparison full cell profile U, and the profile error.

[0203] Here, the profile correction unit 120 can calculate the positive electrode change rate ps of the adjusted reference positive electrode profile Rp' relative to the reference positive electrode profile Rp. The profile correction unit 120 can also calculate the negative electrode change rate ns of the adjusted reference positive electrode profile Rn'' relative to the reference negative electrode profile Rn. For example, the profile correction unit 120 may determine the first scale factor as the positive electrode change rate ps and the second scale factor as the negative electrode change rate ns.

[0204] As described above, the profile correction unit 120 can generate a corresponding comparison full cell profile for each pair of first and second scale factors selected from the scaling numerical range. Since there are multiple pairs of first and second scale factors, it is obvious that multiple comparison full cell profiles will also be generated. After identifying the minimum profile error among the multiple comparison full cell profiles, the profile correction unit 120 can obtain information mapped to the minimum profile error from the storage unit 140.

[0205] The battery diagnostic device 100 according to the present invention is connected to a display device (not shown) and can output information about batteries diagnosed as being in an abnormal state. This allows information about batteries diagnosed as being in an abnormal state to be displayed on the display device.

[0206] The battery diagnostic device 100 according to the present invention is connected to an alarm device (not shown) and can output information about a battery diagnosed as being in an abnormal state, thereby activating the alarm device.

[0207] The battery diagnostic device 100 according to the present invention is applicable to a Battery Management System (BMS). That is, the BMS according to the present invention may include the battery diagnostic device 100 described above. In such a configuration, at least some of the components of the battery diagnostic device 100 can be realized by complementing or adding to the functions of components included in a conventional BMS. For example, the profile acquisition unit 110, profile correction unit 120, control unit 130, and storage unit 140 of the battery diagnostic device 100 can be realized as components of a BMS.

[0208] Furthermore, the battery diagnostic device 100 according to the present invention may be provided in a battery pack. That is, the battery pack according to the present invention may include the aforementioned battery diagnostic device 100 and one or more battery cells. The battery pack may further include electrical components (relays, fuses, etc.) and a case.

[0209] Figure 19 shows an exemplary configuration of a battery pack according to another embodiment of the present invention.

[0210] As shown in Figure 19, the battery pack 1 according to the present invention may include at least one battery 10, a measuring unit 20, and a battery diagnostic device 100 according to the present invention.

[0211] The positive terminal of battery 10 may be connected to the positive terminal P+ of battery pack 1, and the negative terminal of battery 10 may be connected to the negative terminal P- of battery pack 1.

[0212] The measuring unit 20 can be connected to the positive and negative terminals of the battery 10. The measuring unit 20 can then measure the voltage of the battery 10 by measuring the positive and negative potentials of the battery 10 and calculating the difference between the positive and negative potentials.

[0213] Furthermore, the measurement unit 20 may be connected to a current measurement unit A. For example, the current measurement unit A may be an ammeter or shunt resistor that measures the charging and discharging currents of the battery 10. The measurement unit 20 may use the current measurement unit A to measure the charging current of the battery 10 and calculate the charge amount. The measurement unit 20 may also measure the discharging current of the battery 10 via the third sensing line SL3 and calculate the discharge amount.

[0214] For example, information about the voltage and capacity of the battery 10 measured by the measurement unit 20 can be transmitted to the profile acquisition unit 110. The profile acquisition unit 110 can then directly generate a battery profile BP based on the received voltage and capacity information.

[0215] In another example, information about the voltage and capacity of the battery 10 measured by the measurement unit 20 may be stored in the storage unit 140. When charging or discharging of the battery 10 is complete, the profile acquisition unit 110 may access the storage unit 140 to acquire the battery profile BP.

[0216] In yet another example, the measurement unit 20 may directly generate a battery profile BP based on the measured information about the voltage and capacity of the battery 10. In this case, the generated battery profile BP may be transmitted to the profile acquisition unit 110 and also stored in the storage unit 140.

[0217] A charge / discharge device or load may be connected to the positive terminal P+ and negative terminal P- of battery pack 1.

[0218] Figure 20 shows the manufacturing process of a battery cell in a battery manufacturing system according to yet another embodiment of the present invention. Specifically, Figure 20 is a schematic diagram showing the activation process of the manufactured battery cell over time.

[0219] Referring to Figure 20, the aging process takes place in the first stage from time t0 to time t1. Here, the aging process refers to the process of leaving the battery cells under specific conditions. In the first stage, the electrolyte can be impregnated into the battery electrodes.

[0220] In the second stage, from time t1 to time t2, primary charging takes place. In the second stage, a coating layer (SEI, solid electrolyte interphase) may be formed on the negative electrode.

[0221] In the third stage, from time t2 to time t3, a high-temperature aging process is performed. For example, in the third stage, aging is performed under high-temperature conditions of 60°C, which can stabilize the coating layer formed in the second stage.

[0222] In the fourth stage, from time t3 to time t4, a degassing process is performed. In the fourth stage, gases contained inside the battery cells can be removed.

[0223] In the fifth stage, from time t4 to time t5, the battery cells are charged. In the sixth stage, from time t5 to time t6, the battery cells are discharged. Here, the fifth and sixth stages together can be called the battery cell capacity verification stage. Generally, the sixth stage is a stage in which defects in battery cells are detected while discharging fully charged battery cells, and it is a stage in which the battery cells are discharged at a discharge C rate determined considering the verification time and the accuracy of the verification. For example, in the sixth stage, the battery cells are discharged at 0.3C, and a battery profile BP for capacity and voltage can be obtained during the discharge process. Based on the obtained battery profile BP, the presence or absence of defects in the battery cells can be detected as described above.

[0224] In the seventh stage, from time t6 to time t7, a shipping charge process is performed to prepare the battery cells for shipment.

[0225] A battery diagnostic device 100 according to one embodiment of the present invention can acquire a battery profile BP generated in the sixth stage discharge process. Then, by removing the overvoltage included in the battery profile BP using an overvoltage profile OP corresponding to the target C rate set in the discharge process, a correction profile CP for multiple battery cells can be acquired. The battery diagnostic device 100 can then diagnose the state of multiple battery cells based on the multiple correction profiles CP. In other words, by being used in the battery cell activation process, the battery diagnostic device 100 can quickly and accurately diagnose whether or not there are defects in the manufactured battery cells. In particular, since the battery diagnostic device 100 diagnoses the state of the battery cells after removing any overvoltage that may be included in the battery profile BP acquired in the capacity verification process, it has the advantage of being able to detect defective battery cells more accurately.

[0226] Figure 21 is a diagram showing an exemplary configuration of an automobile according to yet another embodiment of the present invention.

[0227] Referring to Figure 21, the battery pack according to an embodiment of the present invention may be included in an automobile 1700 such as an electric vehicle (EV) or a hybrid vehicle (HV). The battery pack 1710 can drive the automobile 1700 by supplying power to the motor via an inverter provided in the automobile 1700. Here, the battery pack 1710 may include a battery management device 100. That is, the automobile 1700 may include a battery management device 100.

[0228] Figure 22 is a schematic diagram illustrating a battery diagnostic method according to yet another embodiment of the present invention.

[0229] The battery diagnostic method may include a profile acquisition stage S100, a corrected profile generation stage S200, a profile adjustment stage S300, a diagnostic factor extraction stage S400, and a state diagnosis stage S500.

[0230] Preferably, each step of the battery diagnostic method may be performed by the battery diagnostic device 100. For the sake of clarity, the following will either omit or briefly explain any content that overlaps with what has been described above.

[0231] The profile acquisition step S100 is a step in which multiple battery profiles BP, each showing the correspondence between the voltage and capacity of multiple batteries, are acquired, and this can be performed by the profile acquisition unit 110.

[0232] For example, the profile acquisition unit 110 can directly receive the battery profile BP from an external source. That is, the profile acquisition unit 110 can acquire the battery profile BP by receiving it via a wired and / or wireless connection to an external source.

[0233] In another example, the profile acquisition unit 110 may receive battery information regarding the battery voltage V and capacity Q. The profile acquisition unit 110 may then generate a battery profile BP based on the received battery information. That is, the profile acquisition unit 110 may acquire the battery profile BP by directly generating the battery profile BP based on the battery information.

[0234] The correction profile generation step S200 is a step in which multiple correction profiles CP are generated by correcting multiple battery profiles BP based on a preset overvoltage profile OP, and this step can be performed by the profile correction unit 120.

[0235] Specifically, the profile correction unit 120 can remove the overvoltage profile OP from the battery profile BP. For example, the profile correction unit 120 can calculate the difference between the voltage of the battery profile BP and the overvoltage of the overvoltage profile OP for the same capacity. The profile correction unit 120 can generate a corrected profile CP by calculating the difference between the voltage of the battery profile BP and the overvoltage of the overvoltage profile OP for the total capacity.

[0236] The profile adjustment step S300 is a step in which a predetermined reference positive electrode profile and a reference negative electrode profile are adjusted to correspond to a plurality of correction profiles CP, respectively, in order to generate an adjusted positive electrode profile and an adjusted negative electrode profile corresponding to each battery, and this step can be performed by the profile correction unit 120.

[0237] For example, the profile correction unit 120 can generate multiple comparison full cell profiles by shifting the reference positive electrode profile and the reference negative electrode profile, or by performing capacitance scaling, and can identify the comparison full cell profile among the multiple comparison full cell profiles that minimizes the error with the correction profile CP. Then, the adjusted positive electrode profile and adjusted negative electrode profile corresponding to the identified comparison full cell profile can be determined.

[0238] The diagnostic factor extraction step S400 is a step in which diagnostic factors for each battery are extracted from at least one of the adjusted positive electrode profile and the adjusted negative electrode profile, and this can be performed by the control unit 130.

[0239] Specifically, when the control unit 130 diagnoses the battery status related to the positive electrode, it can extract diagnostic factors related to the positive electrode from the adjusted positive electrode profile. Furthermore, when the control unit 130 diagnoses the battery status related to the negative electrode, it can extract diagnostic factors related to the negative electrode from the adjusted negative electrode profile. Additionally, when the control unit 130 diagnoses the battery status related to both the positive and negative electrodes, it can extract diagnostic factors related to the positive electrode from the adjusted positive electrode profile and diagnostic factors related to the negative electrode from the adjusted negative electrode profile.

[0240] In this case, positive electrode-related factors may include at least one of the following: positive electrode start potential, positive electrode end potential, positive electrode rate of change, and positive electrode load, based on the adjusted positive electrode profile. Similarly, negative electrode-related factors may include at least one of the following: negative electrode start potential, negative electrode end potential, negative electrode rate of change, and negative electrode load, based on the adjusted negative electrode profile. Factors relating to both positive and negative electrodes may include the NP ratio based on the positive and negative electrode loads.

[0241] The status diagnosis step S500 is a step in which the status of multiple batteries is diagnosed based on the extracted diagnostic factors, and can be performed by the control unit 130.

[0242] For example, the control unit 130 may be configured to select diagnostic factors that fall outside the threshold range TH from among the multiple diagnostic factors, taking into consideration the distribution of multiple diagnostic factors, and to diagnose the battery state corresponding to the selected diagnostic factor as an abnormal state. On the other hand, the control unit 130 may be configured to select diagnostic factors that fall within the threshold range TH from among the multiple diagnostic factors, and to diagnose the battery state corresponding to the selected diagnostic factor as a normal state.

[0243] Furthermore, after the threshold range TH for the diagnostic factor values ​​of a normal battery has been determined for each diagnostic factor, diagnosis of a new battery can be performed by a simplified process that determines whether the values ​​of the diagnostic factors of that battery fall within that threshold range.

[0244] The embodiments of the present invention described above are not necessarily carried out through apparatus and methods, but may also be carried out through a program that performs functions corresponding to the configuration of the embodiments of the present invention, or through a recording medium on which such a program is recorded. Such implementation should be easily carried out by experts in the art to which the present invention belongs, based on the above-described embodiments.

[0245] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and that a wide range of modifications and variations are possible within the equivalent scope of the technical idea and claims of the present invention by persons with ordinary skill in the art to which the present invention pertains.

[0246] Furthermore, since the present invention described above can be substituted, modified, and altered in various ways by a person with ordinary skill in the art to which the present invention belongs, without departing from the technical spirit of the invention, it is not limited by the embodiments described above and the accompanying drawings, and all or part of each embodiment can be selectively combined to form a variety of modifications. [Explanation of Symbols]

[0247] 1 Battery Pack 10 batteries 20 Measuring part 100 Battery diagnostic device 110 Profile acquisition unit 120 Profile Correction Section 130 Control Unit 140 Preservation Department 1700 automobiles 1710 Battery Pack

Claims

1. A profile acquisition unit acquires a battery profile showing the correspondence between the voltage and capacity of a battery to be diagnosed, which is charged or discharged at a predetermined target C rate. A profile correction unit generates a correction profile by correcting the battery profile based on an overvoltage profile that shows the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at the target C rate, and generates an adjusted negative electrode profile that is adjusted to show the correspondence between the negative electrode capacity and the negative electrode potential of the battery to be diagnosed using the correction profile. A battery diagnostic device comprising: a control unit that extracts the negative electrode start potential value from the adjusted negative electrode profile as a diagnostic factor for the battery to be diagnosed, and diagnoses the state of the battery to be diagnosed based on the extracted diagnostic factor.

2. The aforementioned overvoltage profile is The battery diagnostic device according to claim 1, characterized in that it is a profile showing the voltage difference for each capacity between a first battery profile of the reference battery obtained when the reference battery is charged or discharged at a reference C rate, and a second battery profile of the reference battery obtained when the reference battery is charged or discharged at a target C rate.

3. The profile correction unit, The battery diagnostic device according to claim 2, characterized in that it calculates the voltage difference for each capacity between the battery profile and the overvoltage profile and generates the correction profile.

4. The system further includes an overvoltage profile showing the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at a C rate different from the target C rate, and a storage unit for storing the overvoltage profile. The profile correction unit, The battery diagnostic device according to claim 2, characterized in that it selects an overvoltage profile corresponding to the target C rate from among the overvoltage profiles stored in the storage unit, and generates the correction profile using the selected overvoltage profile.

5. The profile correction unit, The battery diagnostic device according to claim 1, characterized in that it generates a comparative full cell profile corresponding to the correction profile by adjusting and synthesizing a predetermined reference positive electrode profile and a reference negative electrode profile, and provides the reference negative electrode profile adjusted to generate the comparative full cell profile as the adjusted negative electrode profile.

6. The control unit, The battery diagnostic device according to claim 1, characterized in that if the negative electrode starting potential value is not within a predetermined threshold range, the battery to be diagnosed is diagnosed as being in an abnormal state.

7. The control unit, The battery diagnostic device according to claim 1, characterized in that one or more of the negative electrode termination potential value, negative electrode change rate, and negative electrode load amount are further extracted as diagnostic factors from the adjusted negative electrode profile, and the state of the battery to be diagnosed is diagnosed based on the extracted diagnostic factors.

8. The control unit, The battery diagnostic device according to claim 7, characterized in that if the values ​​of a predetermined number or more of the extracted diagnostic factors are within their respective corresponding threshold ranges, the battery to be diagnosed is diagnosed as being in a normal state.

9. A battery pack comprising a battery diagnostic device according to any one of claims 1 to 8.

10. A battery manufacturing system comprising a battery diagnostic device according to any one of claims 1 to 8.

11. An automobile comprising a battery diagnostic device according to any one of claims 1 to 8.

12. A profile acquisition step is to acquire a battery profile that shows the correspondence between the voltage and capacity of the battery to be diagnosed when charged or discharged at a predetermined target C rate, A correction profile generation step in which a correction profile is generated by correcting the battery profile based on an overvoltage profile that shows the overvoltage for each capacity of the reference battery that occurs when the reference battery is charged or discharged at the target C rate, A profile adjustment step is to generate an adjusted negative electrode profile that is adjusted to show the correspondence between the negative electrode capacity and the negative electrode potential of the battery to be diagnosed using the correction profile, A diagnostic factor extraction step is performed in which the negative electrode start potential value is extracted from the adjusted negative electrode profile as a diagnostic factor for the battery to be diagnosed. A battery diagnostic method characterized by including a state diagnostic step of diagnosing the state of the battery to be diagnosed based on the negative electrode start potential value.

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