Battery diagnosis device and method

Abstract

A battery diagnosis apparatus according to one embodiment of the present disclosure includes: a curve determination unit configured to determine a negative curve of a battery by adjusting a reference positive curve and a reference negative curve to fit a measured full cell curve indicating a correspondence relationship between a capacity and a voltage of the battery; a load amount calculation unit configured to calculate a negative electrode load amount of the battery based on a negative electrode curve of the battery; and a condition diagnosis unit configured to compare a resistance of the battery with a preset resistance range and a negative electrode load amount of the battery with a preset load amount range, and diagnose a condition of the battery based on a resistance comparison result and a negative electrode load amount comparison result.

Description

Technical Field

[0001] The present disclosure relates to a battery diagnostic apparatus and method, and more particularly to a battery diagnostic apparatus and method for diagnosing whether at least one of an active material, a conductive material, or a binder is included in a negative electrode of a battery in a larger amount, a smaller amount, or an optimal amount.

[0002] This application claims priority from Korean Patent Application No. 10-2023-0126640 filed in Korea on September 21, 2023, the disclosure of which is incorporated herein by reference. Background Art

[0003] In recent years, the demand for portable electronic products such as laptop computers, camcorders, and mobile phones has rapidly increased, and with the widespread development of electric vehicles, accumulators for energy storage, robots, and satellites, much research is being conducted on high-performance batteries that can be repeatedly charged and discharged.

[0004] Currently, commercially available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium batteries, etc., and among them, lithium batteries have little or no memory effect, and therefore they have received more attention than nickel-based batteries because they have the advantages of being rechargeable whenever convenient, having a very low self-discharge rate and a high energy density.

[0005] Battery electrodes are manufactured by coating a slurry containing a mixture of active materials, conductive materials, and binders onto current collector plates. Active materials are materials that generate electrical energy through chemical reactions. For example, in lithium batteries, the positive electrode active material provides lithium ions to the negative electrode during charging, and the negative electrode active material stores and releases lithium ions during discharge. Therefore, the active material affects the capacity and output of the battery. Conductive materials are materials that improve the conduction of electrons between active material particles or between the active material and the metal current collector. Binders are materials that maintain adhesion between the active material and the conductive material, thereby mechanically stabilizing the electrode.

[0006] Therefore, the composition ratio of the active material, the conductive material, and the binder is an important factor in determining the performance of the battery.

[0007] However, due to procedural reasons, the composition ratio of the active material, conductive material, and binder may differ from the designed ratio. When the composition ratio of the active material, conductive material, and binder differs from the designed ratio, the battery performance may also differ from the designed performance. In other words, in order to provide a battery with consistent performance, it is necessary to diagnose whether the composition ratio of the active material, conductive material, and binder of the manufactured battery is consistent with the designed ratio.

[0008] However, after battery manufacturing is complete, it is practically impossible to accurately measure the composition ratio of the active material, conductive material, and binder without disassembling the battery to directly analyze the electrodes. Therefore, a diagnostic technique is needed to diagnose whether the composition ratio of the active material, conductive material, and binder of a manufactured battery is consistent with the designed ratio without disassembling the battery. In other words, a diagnostic technique is needed to diagnose whether at least one of the active material, conductive material, or binder is included in the negative electrode in a large amount, a small amount, or an optimal amount. Summary of the Invention

[0009] Technical issues

[0010] The present disclosure is designed to solve the above-mentioned problems, and therefore the present disclosure aims to provide a battery diagnostic device and method for more conveniently and accurately diagnosing in a non-destructive manner whether at least one of an active material, a conductive material or a binder is included in a larger amount, a smaller amount or an optimal amount in a negative electrode of a battery.

[0011] These and other purposes and advantages of the present disclosure can be understood from the following description and will become apparent from the exemplary embodiments of the present disclosure. Moreover, it will be easily understood that the purposes and advantages of the present disclosure can be achieved by the means set forth in the appended claims and their combinations.

[0012] Technical Solution

[0013] A battery diagnostic device according to one aspect of the present disclosure may include: a curve determination unit configured to determine a negative electrode curve of a battery by adjusting a reference positive electrode curve and a reference negative electrode curve to fit a measured full-cell curve indicating a corresponding relationship between a capacity and a voltage of the battery; a load capacity calculation unit configured to calculate a negative electrode load capacity of the battery based on the negative electrode curve of the battery; and a condition diagnosis unit configured to compare a resistance of the battery with a preset resistance range and compare a negative electrode load capacity of the battery with a preset load capacity range, and diagnose a condition of the battery based on a resistance comparison result and a negative electrode load capacity comparison result.

[0014] The condition diagnosis unit may be configured to diagnose the battery condition as normal when the resistance is within the resistance range and the negative electrode load amount is within the load amount range, and diagnose the battery condition as abnormal when the resistance is not within the resistance range or the negative electrode load amount is not within the load amount range.

[0015] The abnormal condition may be a condition in which at least one of an active material, a binder, or a conductive material is included in a large amount in the negative electrode of the battery.

[0016] The load capacity calculation unit may be configured to calculate the negative electrode load capacity in consideration of a negative electrode change rate of a negative electrode curve of the battery relative to a reference negative electrode curve.

[0017] The load amount calculation unit may be configured to calculate the negative electrode load amount in consideration of a negative electrode change rate, a preset reference negative electrode capacity, and a preset reference area.

[0018] The load amount calculation unit may be configured to calculate the negative electrode load amount indicating the negative electrode capacity per unit area by multiplying a reference negative electrode capacity by a negative electrode change rate and dividing the product by a reference area.

[0019] The resistance range may be a range set based on an average value of resistance distributions of a plurality of reference batteries or based on a standard deviation of the resistance distributions.

[0020] The load capacity range may be a range set based on an average value of negative electrode load capacity distribution of a plurality of reference batteries or based on a standard deviation of the load capacity distribution.

[0021] The battery diagnostic apparatus according to another aspect of the present disclosure may further include a resistance calculation unit configured to calculate resistance of the battery based on measuring the full-cell curve.

[0022] A battery manufacturing system according to still another aspect of the present disclosure may include the battery diagnostic apparatus according to one aspect of the present disclosure.

[0023] A battery pack according to still another aspect of the present disclosure may include the battery diagnostic device according to one aspect of the present disclosure.

[0024] According to another aspect of the present disclosure, a battery diagnosis method may include: a negative electrode curve determination step, which determines the negative electrode curve of the battery by adjusting a reference positive electrode curve and a reference negative electrode curve to adapt a measured full-cell curve indicating the corresponding relationship between the capacity and voltage of the battery; a negative electrode load capacity calculation step, which calculates the negative electrode load capacity of the battery based on the negative electrode curve of the battery; a comparison step, which compares the resistance of the battery with a preset resistance range and compares the negative electrode load capacity of the battery with a preset load capacity range; and a condition diagnosis step, which diagnoses the condition of the battery based on the resistance comparison result and the negative electrode load capacity comparison result of the comparison step.

[0025] Beneficial effects

[0026] According to one aspect of the present disclosure, whether at least one of an active material, a conductive material, or a binder is included in a negative electrode of a battery in a larger amount, a smaller amount, or an optimal amount can be more conveniently and accurately diagnosed in a non-destructive manner.

[0027] Furthermore, according to one aspect of the present disclosure, since the resistance of a battery and the negative electrode load amount are used to diagnose the condition of the battery in a complementary manner, the accuracy of the battery condition diagnosis can be improved.

[0028] Furthermore, according to one aspect of the present disclosure, the condition of the negative electrode can be diagnosed in a detailed and accurate manner based on the resistance comparison results and the negative electrode load comparison results. Furthermore, because the condition of the negative electrode is diagnosed in detail, the cause of manufacturing problems of the corresponding battery can be quickly identified.

[0029] In addition, according to one aspect of the present disclosure, since the capacity of the negative electrodes per unit area is considered when diagnosing the condition of the battery, the condition of the battery can be consistently diagnosed regardless of the total amount of the negative electrodes.

[0030] The effects of the present disclosure are not limited to the above-described effects, and those skilled in the art will clearly understand these and other effects from the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings illustrate exemplary embodiments of the present disclosure and, together with the following detailed description, serve to provide a better understanding of the technical aspects of the present disclosure, and thus the present disclosure should not be construed as limited to the accompanying drawings.

[0032] Figure 1 FIG. 1 is a diagram schematically illustrating a battery diagnosis device according to an embodiment of the present disclosure.

[0033] Figure 2 and Figure 3 is a graph referred to when describing the amounts of active material, conductive material, and binder according to the resistance comparison results and the negative electrode loading amount comparison results.

[0034] Figure 4 is a graph referred to in the example describing each of the reference positive electrode curve and the reference negative electrode curve.

[0035] Figure 5 is a graph referenced in the examples describing the measured all-monomer curve for the target monomer.

[0036] Figures 6 to 8 is a diagram referenced in an example describing a process for generating a comparative whole monomer distribution for comparison with a measured whole monomer distribution according to one embodiment of the present disclosure.

[0037] Figures 9 to 11 is a graph referenced in another example describing a process for generating a comparative whole monomer distribution for comparison with a measured whole monomer distribution according to one embodiment of the present disclosure.

[0038] Figure 12 is a diagram illustrating an exemplary configuration of a battery pack including a battery diagnostic device according to one embodiment of the present disclosure.

[0039] Figure 13 FIG. 1 is a flowchart exemplarily illustrating a battery diagnosis method according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0040] It should be understood that the terms or words used in the specification and the appended claims should not be interpreted as limited to the general and dictionary meanings, but may be interpreted based on the meanings and concepts corresponding to the technical aspects of the present disclosure on the basis of the principle allowing the inventor to appropriately define the terms for the best explanation.

[0041] Therefore, the embodiments described herein and the illustrations shown in the accompanying drawings are exemplary embodiments of the present disclosure for describing the technical aspects of the present disclosure and are not intended to be limiting, and it should be understood that various other equivalents and modifications may have been made thereto at the time of filing this application.

[0042] In describing the present disclosure, detailed descriptions of related known elements or functions, which may make the subject matter of the present disclosure obscure or unclear, are omitted.

[0043] The terms “first,” “second,” etc. are used to distinguish one element from another among various elements, but are not intended to limit the elements by the terms.

[0044] Unless the context clearly indicates otherwise, the terms “comprise” and “comprising” when used in this specification specify the presence of stated elements, but do not preclude the presence or addition of one or more other elements.

[0045] Furthermore, throughout the specification, it will be understood that when an element is referred to as being “connected to” another element, it can be directly connected to the other element or intervening elements may be present.

[0046] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0047] Figure 1 FIG. 1 is a diagram schematically illustrating a battery diagnosis device 100 according to an embodiment of the present disclosure.

[0048] refer to Figure 1 The battery diagnostic device 100 according to one embodiment of the present disclosure may include a curve determination unit 110, a load calculation unit 120, and a condition diagnosis unit 130. The battery diagnostic device 100 may further include a resistance calculation unit 140. The battery diagnostic device 100 may further include a storage unit 150.

[0049] Here, a battery refers to a physically separable and independent unit having a negative terminal and a positive terminal. For example, a lithium-ion battery or a lithium polymer battery can be considered a battery.

[0050] The curve determination unit 110 may be configured to determine the negative electrode curve of the battery by adjusting the reference positive electrode curve and the reference negative electrode curve to fit a measured full-cell curve indicating a corresponding relationship between the capacity and the voltage of the battery.

[0051] Here, the measured full-cell curve is a curve generated based on the capacity and voltage measured during the battery's charge or discharge. For example, the measured full-cell curve may be a curve indicating the corresponding relationship between the capacity and voltage measured during the battery's charge. In other words, the measured full-cell curve may be a capacity (Q)-voltage (V) curve of the battery.

[0052] The reference positive electrode curve may be a curve indicating the corresponding relationship between the capacity and voltage of a preset reference positive electrode cell of the positive electrode of the battery. For example, the reference positive electrode cell may be a positive electrode button-half cell or a positive electrode of a tri-electrode cell. Furthermore, the reference negative electrode curve may be a curve indicating the corresponding relationship between the capacity and voltage of a preset reference negative electrode cell of the negative electrode of the battery. For example, the reference negative electrode cell may be a negative electrode button-half cell or a negative electrode of a tri-electrode cell.

[0053] Specifically, the curve determination unit 110 may adjust the reference positive electrode curve and the reference negative electrode curve to match the measured full-cell curve. More specifically, the curve determination unit 110 may adjust the reference positive electrode curve and the reference negative electrode curve to generate an adjusted positive electrode curve and an adjusted negative electrode curve. Furthermore, the curve determination unit 110 may generate a comparative full-cell curve based on the adjusted positive electrode curve and the adjusted negative electrode curve. The curve determination unit 110 may adjust the reference positive electrode curve and the reference negative electrode curve until the comparative full-cell curve matches the measured full-cell curve.

[0054] For example, the curve determination unit 110 may shift or capacity-scale the reference positive and negative curves to generate a plurality of comparative full-cell curves, and select any one of the comparative full-cell curves having the smallest error with the measured full-cell curve.

[0055] Regarding this, the following reference Figures 4 to 8 An embodiment in which the curve determination unit 110 determines the negative electrode curve of the battery by adjusting the reference positive electrode curve and the reference negative electrode curve to fit the measured full-cell curve is described in more detail.

[0056] The load capacity calculation unit 120 may be configured to calculate the negative electrode load capacity of the battery based on the negative electrode curve of the battery.

[0057] Here, the negative electrode loading of a battery may refer to the amount of negative electrode active material coated on the negative electrode current collector. The negative electrode curve of a battery may be a curve generated based on a reference negative electrode curve and indicating the current condition of the negative electrode of the battery. Therefore, the loading calculation unit 120 may calculate the negative electrode loading of the battery based on the negative electrode curve. An embodiment in which the loading calculation unit 120 calculates the negative electrode loading based on the negative electrode curve will be described below.

[0058] The condition diagnosis unit 130 may be configured to compare the resistance of the battery with a preset resistance range.

[0059] Here, the resistance range may be preset based on resistance distribution of a plurality of reference batteries for the target battery. Preferably, the reference battery may have the same type and specifications as the battery to be diagnosed by the battery diagnosis apparatus 100 (hereinafter referred to as the target battery).

[0060] For example, the resistance range may be set based on the average value and standard deviation of the resistance distribution of multiple reference batteries. Specifically, the resistance range may be set to a range that is 3 standard deviations away from the average value of the resistance distribution of the multiple reference batteries. That is, the lower limit of the resistance range may be set to a value obtained by subtracting 3 standard deviations from the average value, and the upper limit of the resistance range may be set to a value obtained by adding 3 standard deviations to the average value.

[0061] Condition diagnosis unit 130 can determine whether the battery resistance is within a preset resistance range by comparing the battery resistance with a preset resistance range. For example, when the battery resistance is equal to or less than the upper limit of the resistance range and equal to or greater than the lower limit, condition diagnosis unit 130 can determine that the battery resistance is within the resistance range. Conversely, when the battery resistance is greater than the upper limit of the resistance range or less than the lower limit, condition diagnosis unit 130 can determine that the battery resistance is not within the resistance range.

[0062] The condition diagnosis unit 130 may be configured to compare the negative electrode load of the battery with a preset load range.

[0063] Here, the load capacity range may be preset based on the negative electrode load capacity distribution of a plurality of reference batteries corresponding to the target battery.

[0064] For example, the load capacity range may be a range set based on the average and standard deviation of the negative electrode load capacity distribution of multiple reference batteries. Specifically, the load capacity range may be set to a range that is three standard deviations away from the average of the negative electrode load capacity distribution of the multiple reference batteries. In other words, the lower limit of the load capacity range may be set to a value obtained by subtracting three standard deviations from the average, and the upper limit of the load capacity range may be set to a value obtained by adding three standard deviations to the average.

[0065] The condition diagnosis unit 130 can determine whether the battery's negative electrode load capacity is within a preset load capacity range by comparing the battery's negative electrode load capacity with a preset load capacity range. For example, when the battery's negative electrode load capacity is equal to or less than the upper limit of the load capacity range and equal to or greater than the lower limit, the condition diagnosis unit 130 can determine that the battery's negative electrode load capacity is within the load capacity range. Conversely, when the battery's negative electrode load capacity is greater than the upper limit of the load capacity range or less than the lower limit, the condition diagnosis unit 130 can determine that the battery's negative electrode load capacity is not within the load capacity range.

[0066] In one embodiment, the resistance range can be set based on the resistance distribution of multiple reference batteries and the target battery. In addition, the load range can be set based on the negative electrode load distribution of multiple reference batteries and the target battery.

[0067] The condition diagnosis unit 130 may be configured to diagnose the condition of the battery based on the resistance comparison result and the negative electrode load amount comparison result.

[0068] Specifically, the condition diagnosis unit 130 may be configured to diagnose the battery condition as normal when the resistance is within the resistance range and the negative electrode load is within the load range. Conversely, the condition diagnosis unit 130 may be configured to diagnose the battery condition as abnormal when the resistance is not within the resistance range or the negative electrode load is not within the load range.

[0069] The battery diagnostic device 100 according to one embodiment of the present disclosure diagnoses the condition of a battery by considering both the battery resistance and the negative electrode load. That is, according to the battery diagnostic device 100, the battery resistance and the negative electrode load are used to diagnose the battery condition in a complementary manner, thereby improving the accuracy of battery condition diagnosis.

[0070] Meanwhile, the curve determination unit 110, load calculation unit 120, condition diagnosis unit 130, and resistance calculation unit 140 of the battery diagnostic device 100 may selectively include a processor, an application-specific integrated circuit (ASIC), another chipset, a logic circuit, a register, a communication modem, or a data processing device known in the art to execute the various control logics implemented in the present disclosure. Furthermore, when the control logic is implemented as software, each component of the battery diagnostic device 100 may be implemented as a set of program modules.

[0071] The battery diagnostic device 100 may also include a storage unit 150. The storage unit 150 may store data or programs necessary for the various components of the battery diagnostic device 100 to perform operations and functions, or data created during the performance of operations and functions. The storage unit 150 is not limited to a specific type and may include any information storage device capable of recording, erasing, updating, and reading data. As examples, the information storage device may include RAM, flash memory, ROM, EEPROM, or registers. Furthermore, the storage unit 150 may store program code defining the processes that may be executed by each component of the battery diagnostic device 100.

[0072] The condition diagnosis unit 130 can diagnose the condition of the battery as normal or abnormal based on the resistance comparison result and the negative electrode load comparison result. Here, the abnormal condition can be a condition in which at least one of the active material, the conductive material, or the binder is included in the negative electrode of the battery in a large amount.

[0073] The negative electrode of a battery is typically manufactured by coating a slurry containing a mixture of active material, conductive material, and binder onto a current collector plate. Therefore, a battery in an abnormal condition may contain at least one of the active material, conductive material, or binder in a larger amount in the negative electrode.

[0074] Figure 2 and Figure 3 is a graph referred to in describing the amounts of active material, conductive material, and binder according to the resistance comparison results and the negative electrode loading amount comparison results.

[0075] refer to Figure 2 The amount of the conductive material can be determined based on the resistance comparison result, and the amount of the active material can be determined based on the negative electrode loading comparison result.

[0076] Specifically, condition diagnosis unit 140 can diagnose whether the conductive material is included in a large amount, a small amount, or an optimal amount based on the result of comparing the resistance with the resistance range. For example, when the resistance is within the resistance range, condition diagnosis unit 140 can diagnose that the conductive material is included in an optimal amount. When the resistance is greater than the upper limit of the resistance range, condition diagnosis unit 140 can diagnose that the conductive material is included in a large amount. When the resistance is less than the lower limit of the resistance range, condition diagnosis unit 140 can diagnose that the conductive material is included in a small amount.

[0077] Conductive materials are materials that improve the conduction of electrons between active material particles or between the active material and the metal current collector. In other words, they allow current to flow through the battery's electrodes. Therefore, when the proportion of conductive material is low, the battery's resistance increases, while when the proportion of conductive material is high, the battery's resistance decreases.

[0078] Specifically, condition diagnosis unit 140 can diagnose whether the active material is present in a relatively large amount, a relatively small amount, or an optimal amount based on the result of comparing the negative electrode loading amount with the loading amount range. For example, when the negative electrode loading amount is within the loading amount range, condition diagnosis unit 140 can diagnose that the active material is present in an optimal amount. When the negative electrode loading amount is greater than the upper limit of the loading amount range, condition diagnosis unit 140 can diagnose that the active material is present in a relatively large amount. When the negative electrode loading amount is less than the lower limit of the loading amount range, condition diagnosis unit 140 can diagnose that the active material is present in a relatively small amount.

[0079] Active materials are materials that generate electrical energy through chemical reactions. For example, in a lithium battery, the positive electrode active material donates lithium ions to the negative electrode during charging, while the negative electrode active material stores and releases lithium ions during discharge. Therefore, active materials influence the battery's capacity and output. Specifically, as the amount of negative electrode active material increases, the negative electrode's capacity increases. In other words, as the amount of negative electrode active material increases, the negative electrode loading, or the negative electrode capacity per unit area, increases.

[0080] refer to Figure 3 The amount of binder can be indirectly determined based on the amount of active material and the amount of conductive material. That is, assuming the amount of slurry containing a mixture of active material, conductive material, and binder is constant, the amount of binder can be determined based on the amount of conductive material and the amount of active material. For example, condition diagnosis unit 140 can diagnose whether the active material is included in a large amount, a small amount, or an optimal amount.

[0081] There are nine embodiments in total, depending on the amount of each of the active material, the conductive material, and the binder. One embodiment is an embodiment in which the active material, the conductive material, and the binder are all included in optimal amounts. A total of eight embodiments are embodiments in which at least one of the active material, the conductive material, or the binder is included in a relatively large amount.

[0082] When the resistance is greater than the upper limit of the resistance range and the negative electrode loading is greater than the upper limit of the loading range, condition diagnosis unit 130 may diagnose that the conductive material is included in a small amount and the active material is included in a large amount. Furthermore, the binder may be included in a large amount, a small amount, or an optimal amount. The amount of the binder may be determined based on the amount of the conductive material and the amount of the active material.

[0083] When the resistance is greater than the upper limit of the resistance range and the negative electrode loading amount is less than the lower limit of the loading amount range, the condition diagnosis unit 130 may diagnose that the conductive material is included in a smaller amount, the active material is included in a smaller amount, and the binder is included in a larger amount.

[0084] When the resistance is greater than the upper limit of the resistance range and the negative electrode loading amount is within the loading amount range, the condition diagnosis unit 130 may diagnose that the conductive material is included in a smaller amount, the active material is included in an optimal amount, and the binder is included in a larger amount.

[0085] When the resistance is less than the lower limit of the resistance range and the negative electrode loading amount is greater than the upper limit of the loading amount range, the condition diagnosis unit 130 may diagnose that the conductive material is included in a larger amount, the active material is included in a larger amount, and the binder is included in a smaller amount.

[0086] When the resistance is less than the lower limit of the resistance range and the negative electrode loading is less than the lower limit of the loading range, condition diagnosis unit 130 may diagnose that the conductive material is included in a large amount and the active material is included in a small amount. Furthermore, the binder may be included in a large amount, a small amount, or an optimal amount. The amount of the binder may be determined based on the amount of the conductive material and the amount of the active material.

[0087] When the resistance is less than the lower limit of the resistance range and the negative electrode loading amount is within the loading amount range, the condition diagnosis unit 130 may diagnose that the conductive material is included in a larger amount, the active material is included in an optimal amount, and the binder is included in a smaller amount.

[0088] When the resistance is within the resistance range and the negative electrode loading amount is greater than the upper limit of the loading amount range, the condition diagnosis unit 130 may diagnose that the conductive material is included in an optimal amount, the active material is included in a larger amount, and the binder is included in a smaller amount.

[0089] When the resistance is within the resistance range and the negative electrode loading amount is less than the lower limit of the loading amount range, the condition diagnosis unit 130 may diagnose that the conductive material is included in an optimal amount, the active material is included in a smaller amount, and the binder is included in a larger amount.

[0090] When the resistance is within the resistance range and the negative electrode loading amount is within the loading amount range, the condition diagnosis unit 130 may diagnose that the active material, the conductive material, and the binder are included in optimal amounts.

[0091] The battery diagnostic device 100 according to one embodiment of the present disclosure can diagnose the condition of the negative electrode in a detailed and accurate manner based on the resistance comparison results and the negative electrode load comparison results. In addition, because the condition of the negative electrode is diagnosed in detail, the cause of the manufacturing problem of the battery can be quickly identified.

[0092] Hereinafter, an embodiment in which the load amount calculation unit 120 calculates the negative electrode load amount according to the negative electrode curve will be described in detail.

[0093] The load capacity calculation unit 120 may be configured to calculate the negative electrode load capacity in consideration of a negative electrode change rate of a negative electrode curve of the battery relative to a reference negative electrode curve.

[0094] Here, the negative electrode change rate may refer to the change rate [%] of the negative electrode curve of the battery relative to the reference negative electrode curve. Specifically, the negative electrode change rate may be the contraction or expansion rate of the negative electrode curve of the battery relative to the reference negative electrode curve.

[0095] For example, when the negative electrode curve of the battery is generated by 10% contraction of the reference negative electrode curve, the negative electrode change rate is 90%. When the negative electrode curve of the battery is generated by 10% expansion of the reference negative electrode curve, the negative electrode change rate is 110%.

[0096] That is, when the negative electrode change rate is less than 100%, the negative electrode curve of the battery is generated by contracting the reference negative electrode curve. When the negative electrode change rate is greater than 100%, the negative electrode curve of the battery is generated by expanding the reference negative electrode curve. In addition, when the negative electrode change rate is 100%, the negative electrode curve of the battery is generated without contracting or expanding the reference negative electrode curve.

[0097] Specifically, the load amount calculation unit 120 may be configured to calculate the negative electrode load amount in consideration of the negative electrode change rate, a preset reference negative electrode capacity, and a preset reference area.

[0098] Here, the reference negative electrode capacity may refer to a preset capacity of a reference negative electrode cell, and the reference area may refer to a preset area of ​​a reference negative electrode cell.

[0099] Specifically, the load amount calculation unit 120 may be configured to calculate the negative electrode capacity per unit area as the negative electrode load amount by multiplying a reference negative electrode capacity by a negative electrode change rate and dividing the product by a reference area.

[0100] Because the negative electrode change rate is the rate of change of the battery's negative electrode curve relative to the reference negative electrode curve, the battery's negative electrode capacity can be calculated by multiplying the reference negative electrode capacity by the negative electrode change rate. When the calculated battery's negative electrode capacity is divided by the reference area, the negative electrode loading amount, which indicates the negative electrode capacity per unit area in the battery, can be calculated.

[0101] In other words, when the reference negative electrode capacity is divided by the reference area, the reference negative electrode capacity per unit area can be calculated. When the reference negative electrode capacity per unit area is multiplied by the negative electrode change rate, the negative electrode capacity per unit area in the battery can be calculated.

[0102] Specifically, the load amount calculation unit 120 may calculate the negative electrode load amount based on the negative electrode change rate, the reference negative electrode capacity, and the reference area by using the following Equation 1.

[0103] [Equation 1]

[0104]

[0105] Here, N-loading represents the negative electrode load, and ns represents the negative electrode change rate. r represents the reference negative electrode capacity, and A nc Indicates the reference area.

[0106] For example, when the area of ​​the battery is equal to the reference area, the area of ​​the battery may be replaced with the reference area.

[0107] [Equation 2]

[0108]

[0109] Here, A fc In equation 2, A nc Replace A fc , so Equation 1 can be derived from Equation 2. For example, the negative electrode loading amount calculated by multiplying the reference negative electrode capacity by the negative electrode change rate and dividing the product by the area of ​​the battery can be equal to the negative electrode loading amount calculated according to Equation 1.

[0110] As another example, when the battery area differs from the reference area, area scaling is required. Specifically, the reference negative electrode capacity is multiplied by the negative electrode change rate, the product is divided by the battery area, and the result is multiplied by the area ratio. Here, the area ratio may refer to the ratio of the battery area to the area of ​​the reference negative electrode cell. For example, the area ratio may be calculated as the ratio of the battery area to the reference area.

[0111] For example, when the area of ​​the battery is different from the reference area, the load amount calculation unit 120 may calculate the negative electrode load amount using the following Equation 3.

[0112] [Equation 3]

[0113]

[0114] In Equation 3, when A fc When is eliminated, the result may be Equation 1. That is, when the area of ​​the battery is equal to the reference area and when the area of ​​the battery is not equal to the reference area, the negative electrode capacity per unit area (N-loading) may be calculated according to Equation 1.

[0115] Because the battery diagnostic apparatus 100 considers the negative electrode capacity per unit area when diagnosing the condition of the battery, the condition of the battery can be consistently diagnosed regardless of the total amount of the negative electrodes.

[0116] The battery diagnostic apparatus 100 according to one embodiment of the present disclosure may further include a resistance calculation unit 140 configured to calculate the resistance of the battery based on the measured full-cell curve (M).

[0117] Specifically, the resistance calculation unit 140 may be configured to calculate the resistance of the battery by calculating a voltage difference between a first voltage at a first time and a second voltage at a second time and a ratio of a current amount from the first time to the second time. Here, the first time and the second time are different times.

[0118] For example, when the second time is 10 seconds later than the first time, the resistance calculated by the resistance calculation unit 140 may be the 10-second resistance (R10) of the battery. That is, the resistance calculation unit 140 may calculate the resistance of the battery based on the voltage change for a predetermined period of time (e.g., 10 seconds).

[0119] Generally, the resistance of a battery can be calculated by Ohm's law, which states the ratio of voltage to current. Therefore, the resistance calculation unit 140 can calculate the resistance of the battery by calculating the equation "(second voltage-first voltage)÷current".

[0120] The following is a detailed description of an embodiment in which the curve determination unit 110 determines the negative electrode curve of the battery by adjusting the reference positive electrode curve and the reference negative electrode curve to fit the measured full-cell curve.

[0121] Figure 4 is a graph referred to in the example describing each of the reference positive electrode curve (Rp) and the reference negative electrode curve (Rn). Figure 4 In the graph of , the horizontal axis (X-axis) indicates capacity (Ah), and the vertical axis (Y-axis) indicates voltage (V).

[0122] Figure 5 is the graph referenced in the example describing the measured all-monomer curve (M) of the target monomer. Figure 5 In the graph of , the horizontal axis (X-axis) indicates capacity (Ah), and the vertical axis (Y-axis) indicates voltage (V).

[0123] The curve determination unit 110 may be configured to compare the measured full-cell curve (M) with at least one comparative full-cell curve. Here, the comparative full-cell curve may be the result of adjusting each of the reference positive electrode curve (Rp) and the reference negative electrode curve (Rn) stored in the storage unit 150 to generate an adjusted positive electrode curve and an adjusted negative electrode curve, and synthesizing (combining) the adjusted positive electrode curve and the adjusted negative electrode curve.

[0124] That is, when the reference full-cell curve (R) is the result of subtracting a portion of the reference negative curve (Rn) from a portion of the reference positive curve (Rp), the comparative full-cell curve may be the result of subtracting a portion of the adjusted negative curve from a portion of the adjusted positive curve.

[0125] Curve determination unit 110 can generate at least one comparative full-cell curve by directly adjusting the reference positive electrode curve (Rp) and the reference negative electrode curve (Rn). Alternatively, the at least one comparative full-cell curve can be pre-stored in storage unit 150 based on the reference positive electrode curve (Rp) and the reference negative electrode curve (Rn). In this case, curve determination unit 110 can retrieve the comparative full-cell curve by accessing storage unit 150.

[0126] The curve determination unit 110 can generate multiple comparative full-cell curves based on the reference positive curve (Rp) and the reference negative curve (Rn) by repeatedly adjusting each of the reference positive curve (Rp) and the reference negative curve (Rn) to multiple levels and synthesizing them. The comparative full-cell curves can be referred to as "adjusted reference full-cell curves."

[0127] The curve determining unit 110 may select any one comparative whole monomer curve having the smallest error with the measured whole monomer curve (M) among the plurality of comparative whole monomer curves.

[0128] Subsequently, the curve determination unit 110 may determine the adjusted positive electrode curve and the adjusted negative electrode curve mapped to the selected comparative full-cell curve as the positive electrode curve and the negative electrode curve of the battery.

[0129] In this regard, various known methods at the time of filing this application can be used to determine the error between two curves, each of which is represented in a two-dimensional coordinate system. For example, the integral of the absolute value of the area between the two curves or the root mean square error (RMSE) can be used as the error between the two curves.

[0130] According to this configuration of the present disclosure, various battery condition information can be obtained based on the finalized positive and negative electrode curves. The finalized positive and negative electrode curves can be mapped to the comparative full-cell curve with minimal error. In particular, the comparative full-cell curve derived from the finalized positive and negative electrode curves can nearly match the measured full-cell curve (M).

[0131] Therefore, according to the present disclosure, the positive and negative electrode curves of a battery can be obtained in a non-destructive manner.

[0132] In the case of a new battery, analysis of the positive and negative curves of the battery can be used to diagnose whether any defects have occurred in the battery, and if so, to more easily diagnose the type of defect.

[0133] When a battery verified to be good is in use, the degradation level of the battery can be determined for each degradation item through the positive electrode curve and the negative electrode curve of the battery.

[0134] Furthermore, according to one embodiment of the present disclosure, a battery's positive and negative electrode curves can be obtained in a simple manner. This disclosure can be implemented even when only one reference positive electrode curve (Rp) and one reference negative electrode curve (Rn) are stored in the storage unit 150. In other words, it is not necessary to store multiple reference positive electrode curves (Rp) and / or multiple reference negative electrode curves (Rn) in the storage unit 150. Consequently, the storage unit 150 does not require a high storage capacity, and the extensive pre-testing required for multiple reference positive electrode curves (Rp) and / or multiple reference negative electrode curves (Rn) is unnecessary.

[0135] Figures 6 to 8 is a diagram referred to in an example of describing a process for generating a comparative full-monomer curve for comparison with a measured full-monomer curve (M) according to one embodiment of the present disclosure.

[0136] As reference Figures 6 to 8 The described procedure for generating comparative all-monomer curves is performed in the following order: a first routine (see Figure 4 ), the second routine that performs the curve shift (see Figure 5 ) and a third routine that performs capacity scaling (see Figure 6 ). That is, the process for generating a comparative full monomer curve according to one embodiment of the present disclosure includes first to third routines.

[0137] First, refer to Figure 6 , the reference positive curve (Rp) and the reference negative curve (Rn) are Figure 4 The same as those shown in .

[0138] The curve determination unit 110 determines a positive electrode participation starting point (pi), a positive electrode participation end point (pf), a negative electrode participation starting point (ni), and a negative electrode participation end point (nf) on a reference positive electrode curve (Rp) and a reference negative electrode curve (Rn).

[0139] Either the positive electrode participation starting point (pi) or the negative electrode participation starting point (ni) depends on the other.

[0140] As an example, curve determination unit 110 may divide the positive voltage range from the start point to the end point (or the second set voltage) of the reference positive curve (Rp) into multiple voltage sub-ranges and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the positive electrode participation starting point (pi). Each voltage sub-range may have a predetermined size (e.g., 0.01V). Subsequently, curve determination unit 110 may set a point on the reference negative curve (Rn) that is lower than the positive electrode participation starting point (pi) by a first set voltage (e.g., 3V) as the negative electrode participation starting point (ni).

[0141] As another example, curve determination unit 110 may divide the negative voltage range from the start point to the end point of the reference negative curve (Rn) into multiple voltage sub-ranges of predetermined sizes and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the negative pole participation starting points (ni). Subsequently, curve determination unit 110 may search the reference positive curve (Rp) for a point that is a first set voltage greater than the negative pole participation starting point (ni) and set the found point as the positive pole participation starting point (pi).

[0142] Either the positive electrode participation endpoint (pf) or the negative electrode participation endpoint (nf) is dependent on the other.

[0143] As an example, curve determination unit 110 may divide the voltage range from the second set voltage to the endpoint of the reference positive polarity curve (Rp) into multiple voltage sub-ranges of predetermined sizes, and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the positive polarity participation endpoint (pf). Subsequently, curve determination unit 110 may set a point on the reference negative polarity curve (Rn) that is lower than the positive polarity participation endpoint (pf) by a second set voltage (e.g., 4V) as the negative polarity participation endpoint (nf).

[0144] As another example, curve determination unit 110 may divide the negative electrode voltage range from the start point to the end point of the reference negative electrode curve (Rn) into multiple voltage sub-ranges of predetermined sizes and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the negative electrode participation end point (nf). Subsequently, curve determination unit 110 may search the reference positive electrode curve (Rp) for a point that is a second set voltage greater than the negative electrode participation end point (nf) and set the found point as the positive electrode participation end point (pf).

[0145] When the determination of the positive electrode participation starting point (pi), the positive electrode participation end point (pf), the negative electrode participation starting point (ni), and the negative electrode participation end point (nf) is completed, the curve determination unit 110 shifts at least one of the reference positive electrode curve (Rp) and the reference negative electrode curve (Rn) to the left or right along the horizontal axis.

[0146] refer to Figure 7 , the curve determination unit 110 may shift the reference positive electrode curve (Rp) to the left (lower capacity), or shift the reference negative electrode curve (Rn) to the right (higher capacity), either individually or in combination, to match the capacity values ​​of the positive electrode participation starting point (pi) and the negative electrode participation starting point (ni).

[0147] Alternatively, the curve determination unit 110 may shift the reference positive electrode curve (Rp) to the left, or shift the reference negative electrode curve (Rn) to the right, individually or in combination, to match the capacity values ​​of the positive electrode participation endpoint (pf) and the negative electrode participation endpoint (nf).

[0148] Figure 7 The figure shows a case where the capacity value at the positive electrode participation starting point (pi') matches the capacity value at the negative electrode participation starting point (ni) by simply shifting the reference positive electrode curve (Rp) to the left to generate the adjusted reference positive electrode curve (Rp'). The adjusted reference positive electrode curve (Rp') is the result of applying the adjustment process used to shift the capacity difference between the positive electrode participation starting point (pi) and the negative electrode participation starting point (ni) to the reference positive electrode curve (Rp) to the left. As a result, the voltages at the two points (pi, pi') are the same, differing only in the capacity values. The voltages at the two points (pf, pf') are the same, differing only in the capacity values.

[0149] When generating the adjusted curve (Rp′, Rn) by shifting at least one of the reference positive curve (Rp) and the reference negative curve (Rn), the curve determination unit 110 scales a capacity range of at least one of the adjusted curves (Rp′, Rn).

[0150] according to Figure 7 In the example shown in , the curve determining unit 110 performs an additional adjustment process to shrink or expand at least one of the adjusted reference positive polarity curve (Rp′) or the reference negative polarity curve (Rn) along the horizontal axis.

[0151] refer to Figure 8 , curve determination unit 110 may shrink or expand the adjusted reference positive curve (Rp') to generate an adjusted reference positive curve (Rp') so as to match the capacity range between two points (pi', pf') of the adjusted reference positive curve (Rp') with the capacity range of the measured full-cell curve (M). In this case, either of the two points (pi', pf') may be fixed. Thus, the capacity range between the two points (pi', pf') of the adjusted reference positive curve (Rp'') may match the capacity range of the measured full-cell curve (M).

[0152] Furthermore, the curve determination unit 110 may shrink or expand the reference negative electrode curve (Rn) to generate an adjusted reference negative electrode curve (Rn') so that the capacity range between two points (ni, nf) of the reference negative electrode curve (Rn) matches the capacity range of the measured full-cell curve (M). In this case, either of the two points (ni, nf) may be fixed. Thus, the capacity range between the two points (ni, nf') of the adjusted reference negative electrode curve (Rn') can match the capacity range of the measured full-cell curve (M).

[0153] exist Figure 8 The adjusted reference positive curve (Rp'') is the contraction Figure 7 The results of the adjusted reference positive curve (Rp') shown in the figure and the adjusted reference negative curve (Rn') are the expansion Figure 7 Results for the reference negative electrode curve (Rn) are shown in .

[0154] The positive electrode participation endpoint (pf'') on the adjusted reference positive electrode curve (Rp'') corresponds to the positive electrode participation endpoint (pf') on the adjusted reference positive electrode curve (Rp'). The negative electrode participation endpoint (nf') on the adjusted reference negative electrode curve (Rn') corresponds to the negative electrode participation endpoint (nf) on the reference negative electrode curve (Rn).

[0155] The capacity range between the positive electrode participation start (pi') and the positive electrode participation end (pf') of the adjusted reference positive electrode curve (Rp'') matches the capacity range of the measured full-cell curve (M). Similarly, the capacity range between the negative electrode participation start (ni) and the negative electrode participation end (nf') of the adjusted reference negative electrode curve (Rn') matches the capacity range of the measured full-cell curve (M).

[0156] Furthermore, the capacity range between the two points (pi', pf') of the adjusted reference positive electrode curve (Rp') matches the capacity range between the two points (ni, nf') of the adjusted reference negative electrode curve (Rn'). The curve determination unit 110 may subtract the curve between the two points (pi', pf') of the adjusted reference positive electrode curve (Rp') from the curve between the two points (ni, nf') of the adjusted reference negative electrode curve (Rn') to generate a comparative full-cell curve (S).

[0157] The curve determination unit 110 may calculate an error (curve error) between the comparison all-monomer curve (S) and the measurement all-monomer curve (M).

[0158] The curve determination unit 110 may map and store at least two of the adjusted reference positive electrode curve (Rp'), the adjusted reference negative electrode curve (Rn'), the positive electrode participation starting point (pi'), the positive electrode participation end point (pf'), the negative electrode participation starting point (ni), the negative electrode participation end point (nf'), a first scaling factor, a second scaling factor, a comparative full-cell curve (S), and a curve error in the storage unit 150. The first scaling factor may indicate the ratio of the capacity difference between two points (pi', pf'') to the capacity difference between two points (pi0, pf0). The second scaling factor may indicate the ratio of the capacity difference between two points (ni, nf') to the capacity difference between two points (ni0, nf0).

[0159] Here, the curve determination unit 110 may calculate the positive polarity change rate (ps) of the adjusted reference positive polarity curve (Rp") relative to the reference positive polarity curve (Rp). Additionally, the curve determination unit 110 may calculate the negative polarity change rate (ns) of the adjusted reference negative polarity curve (Rn') relative to the reference negative polarity curve (Rn). For example, the curve determination unit 110 may determine the first scaling factor as the positive polarity change rate (ps) and the second scaling factor as the negative polarity change rate (ns).

[0160] Meanwhile, as described above, when the positive voltage range of the reference positive curve (Rp) is divided into multiple voltage sub-ranges, boundary points of two adjacent voltage sub-ranges among the multiple voltage sub-ranges may be set as positive participation starting points (pi).

[0161] For example, when the positive electrode voltage range of the reference positive electrode curve (Rp) is divided into 100 voltage sub-ranges, the number of boundary points that can be set as the positive electrode participation start point (pi) can be 100. Furthermore, when the voltage range equal to or greater than the second set voltage in the reference positive electrode curve (Rp) is divided into 40 voltage sub-ranges, the number of boundary points that can be set as the positive electrode participation end point (pf) can be 40. In this case, a maximum of 4,000 different comparative full-cell curves can be generated.

[0162] Those skilled in the art will readily appreciate that as the size of the voltage sub-range decreases, the maximum possible number of compared full-cell curves increases, and conversely, as the size of the voltage sub-range increases, the maximum possible number of compared full-cell curves decreases.

[0163] The curve determination unit 110 can identify the minimum curve error among the curve errors of the multiple comparative full-monomer curves generated as described above, and obtain information mapped to the minimum curve error from the storage unit 150 (for example, at least one of the positive pole participation starting point, the positive pole participation end point, the negative pole participation starting point, the negative pole participation end point, the first scaling factor, and the second scaling factor).

[0164] Figures 9 to 11 is a diagram referenced in another example of a process for generating a comparative full-cell curve for comparison with a measured full-cell curve according to one embodiment of the present disclosure. Figures 9 to 11 The embodiment is independent of Figures 6 to 8 Therefore, it should be understood that in describing the embodiment according to Figures 6 to 8 Embodiments and basis Figures 9 to 11 The common terms or symbols among the embodiments are limited to each embodiment.

[0165] As referenced below Figures 9 to 11 The described process for generating comparative full monomer curves is performed in the following order: the fourth routine for capacity scaling is performed (see Figure 9 ), set the fourth point (positive pole participation start point, positive pole participation end point, negative pole participation start point, negative pole participation end point) of the fifth routine (see Figure 10 ) and a sixth routine that performs curve shifting (see Figure 11 ). That is, the process for generating a comparative full monomer curve according to another embodiment of the present disclosure includes fourth to sixth routines.

[0166] refer to Figure 9 , the reference positive curve (Rp) and the reference negative curve (Rn) are Figure 4 The same as those shown in .

[0167] The curve determination unit 110 applies a first scaling factor and a second scaling factor selected from the scaling value range to the reference positive polarity curve (Rp) and the reference negative polarity curve (Rn), respectively, to generate an adjusted reference positive polarity curve (Rp′) and an adjusted reference negative polarity curve (Rn′).

[0168] The scaling value range can be preset or can vary based on the ratio of the capacity range of the measured full-cell curve (M) to the capacity range of the reference full-cell curve (R). For example, when the first and second scaling factors can be selected from a scaling value range (e.g., 90% to 99%) with 0.1% intervals (i.e., 90%, 90.1%, 90.2%, ..., 98.9%, 99%), 91 values ​​can be selected as each of the first and second scaling factors. In this case, a maximum of 8,281 adjusted curve pairs can be generated based on 91 × 91 = 8,281 adjustment levels (combinations of first and second scaling factors). An adjusted curve pair refers to a combination of an adjusted positive electrode curve and an adjusted negative electrode curve.

[0169] Figure 9The adjusted reference positive polarity curve (Rp') and the adjusted reference negative polarity curve (Rn') shown in are the result of applying a first scaling factor and a second scaling factor less than 100% to the reference positive polarity curve (Rp) and the reference negative polarity curve (Rn), respectively.

[0170] Because the first and second scaling factors are less than 100%, the adjusted reference positive polarity curve (Rp') is the result of shrinking the reference positive polarity curve (Rp) along the horizontal axis, and the adjusted reference negative polarity curve (Rn') is also the result of shrinking the reference negative polarity curve (Rn) along the horizontal axis. To facilitate understanding, while the starting point of each of the positive polarity curve (Rp) and the reference negative polarity curve (Rn) remains fixed, the remaining portion shrinks toward the left along the horizontal axis.

[0171] refer to Figure 10 The curve determination unit 110 determines the positive electrode participation starting point (pi'), the positive electrode participation end point (pf'), the negative electrode participation starting point (ni') and the negative electrode participation end point (nf') on the adjusted reference positive electrode curve (Rp') and the adjusted reference negative electrode curve (Rn').

[0172] Either the positive electrode participation starting point (pi') or the negative electrode participation starting point (ni') can be dependent on the other. Furthermore, either the positive electrode participation end point (pf') or the negative electrode participation end point (nf') can be dependent on the other. Furthermore, either the positive electrode participation starting point (pi') or the positive electrode participation end point (pf') can be set based on the other.

[0173] That is, when any one of the positive electrode participation starting point (pi'), the positive electrode participation end point (pf'), the negative electrode participation starting point (ni') and the negative electrode participation 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 capacity range for measuring the full cell distribution (M) (for example, the charge capacity at SOC 0 to 100%).

[0174] As an example, curve determination unit 110 may divide the positive electrode voltage range from the start point to the end point (or the second set voltage) of the adjusted reference positive electrode curve (Rp') into multiple voltage sub-ranges and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the positive electrode participation starting point (pi'). Subsequently, curve determination unit 110 may set a point on the adjusted reference negative electrode curve (Rn) that is lower than the positive electrode participation starting point (pi') by a first set voltage (e.g., 3V) as the negative electrode participation starting point (ni').

[0175] As another example, curve determination unit 110 may divide the negative electrode voltage range from the start point to the end point of the adjusted reference negative electrode curve (Rn') into multiple voltage sub-ranges of predetermined sizes, and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the negative electrode participation starting point (ni'). Subsequently, curve determination unit 110 may search the adjusted reference positive electrode curve (Rp') for a point that is greater than the negative electrode participation starting point (ni') by a first set voltage, and set the found point as the positive electrode participation starting point (pi').

[0176] As another example, curve determination unit 110 may divide the voltage range from the second set voltage to the endpoint of the adjusted reference positive polarity curve (Rp') into multiple voltage sub-ranges of predetermined sizes, and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the positive polarity participation endpoint (pf'). Subsequently, curve determination unit 110 may search the adjusted reference negative polarity curve (Rn') for a point that is lower than the positive polarity participation endpoint (pf') by a second set voltage (e.g., 4V), and set the found point as the negative polarity participation endpoint (nf').

[0177] As another example, curve determination unit 110 may divide the negative electrode voltage range from the start point to the end point of the adjusted reference negative electrode curve (Rn') into multiple voltage sub-ranges of predetermined sizes, and set the boundary points of two adjacent voltage sub-ranges within the multiple voltage sub-ranges as the negative electrode participation end point (nf'). Subsequently, curve determination unit 110 may search the adjusted reference positive electrode curve (Rp') for a point that is a second set voltage greater than the negative electrode participation end point (nf'), and set the found point as the positive electrode participation end point (pf').

[0178] When any one of the positive pole participation starting point (pi'), the positive pole participation end point (pf'), the negative pole participation starting point (ni'), and the negative pole participation end point (nf') is determined, the curve determination unit 110 may additionally determine the remaining three points based on the determined point.

[0179] As an example, after first determining the positive electrode participation starting point (pi'), the curve determination unit 110 may set a point on the adjusted reference positive electrode curve (Rp') having a capacity value greater than the positive electrode participation starting point (pi') by an amount corresponding to the capacity range of the measured full-cell curve (M) as the positive electrode participation end point (pf'). Alternatively, the curve determination unit 110 may search the adjusted reference negative electrode curve (Rn') for a point whose voltage is lower than the positive electrode participation starting point (pi') by a first set voltage and set the found point as the negative electrode participation starting point (ni'). Alternatively, the curve determination unit 110 may set a point on the adjusted reference negative electrode curve (Rn') having a capacity value greater than the negative electrode participation starting point (ni') by an amount corresponding to the capacity range of the measured full-cell curve (M) as the negative electrode participation end point (nf').

[0180] As another example, when the positive electrode participation endpoint (pf') is first determined, the curve determination unit 110 may set a point on the adjusted reference positive electrode curve (Rp') having a capacity value smaller than the capacity value at the positive electrode participation endpoint (pf') by the capacity range of the measured full-cell curve (M) as the positive electrode participation starting point (pi'). Alternatively, the curve determination unit 110 may search the adjusted reference negative electrode curve (Rn') for a point that is a second set voltage lower than the voltage at the positive electrode participation endpoint (pf') and set the found point as the negative electrode participation endpoint (nf'). Furthermore, the curve determination unit 110 may set a point on the adjusted reference negative electrode curve (Rn') having a capacity value smaller than the capacity value at the negative electrode participation endpoint (nf') by the capacity range of the measured full-cell curve (M) as the negative electrode participation starting point (ni').

[0181] As another example, once the negative electrode participation starting point (ni') has been determined, the curve determination unit 110 may set a point on the adjusted reference negative electrode curve (Rn') having a capacity value greater than the capacity value of the negative electrode participation starting point (ni') by an amount equal to the capacity range of the measured full-cell curve (M) as the negative electrode participation end point (nf'). Alternatively, the curve determination unit 110 may search the adjusted reference positive electrode curve (Rp') for a point that is lower than the voltage of the negative electrode participation starting point (ni') by a first set voltage and set the found point as the positive electrode participation starting point (pi'). Furthermore, the curve determination unit 110 may set a point on the adjusted reference positive electrode curve (Rp') having a capacity value greater than the capacity value of the positive electrode participation starting point (pi') by an amount equal to the capacity range of the measured full-cell curve (M) as the positive electrode participation end point (pf').

[0182] As another example, when the negative electrode participation endpoint (nf') is determined, the curve determination unit 110 may set a point on the adjusted reference negative electrode curve (Rn') having a capacity value smaller than the capacity value of the negative electrode participation endpoint (nf') by an amount corresponding to the capacity range of the measured full-cell curve (M) as the negative electrode participation starting point (ni'). Alternatively, the curve determination unit 110 may search the adjusted reference positive electrode curve (Rp') for a point that is a second set voltage lower than the voltage of the negative electrode participation endpoint (nf') and set the found point as the positive electrode participation endpoint (pf'). Alternatively, the curve determination unit 110 may set a point on the adjusted reference positive electrode curve (Rp') having a capacity value smaller than the capacity value of the positive electrode participation endpoint (pf') by an amount corresponding to the capacity range of the measured full-cell curve (M) as the positive electrode participation starting point (pi').

[0183] When the determination of the positive electrode participation starting point (pi'), the positive electrode participation end point (pf'), the negative electrode participation starting point (ni'), and the negative electrode participation end point (nf') is completed based on the pair of the first scaling factor and the second scaling factor, the curve determination unit 110 can shift at least one of the adjusted reference positive electrode curve (Rp') and the adjusted reference negative electrode curve (Rn') to the left or right along the horizontal axis to match the capacity values ​​of the positive electrode participation starting point (pi') and the negative electrode participation starting point (ni') or to match the capacity values ​​of the positive electrode participation end point (pf') and the negative electrode participation end point (nf').

[0184] Figure 11 The adjusted reference negative electrode curve (Rn'') shown in Figure 10 The adjusted reference negative electrode curve (Rn') shown in Figure 1 is shifted to the right. Therefore, the capacity values ​​at the positive electrode participation starting point (pi') and the negative electrode participation starting point (ni'') match each other. Regarding this, because the capacity difference between the positive electrode participation starting point (pi') and the positive electrode participation end point (pf') is equal to the capacity difference between the negative electrode participation starting point (ni') and the negative electrode participation end point (nf'), when the capacity values ​​at the positive electrode participation starting point (pi') and the negative electrode participation starting point (ni'') match each other, the capacity values ​​at the positive electrode participation end point (pf') and the negative electrode participation end point (nf'') also match each other.

[0185] refer to Figure 11 , the curve determination unit 110 may subtract the partial curve between two points (pi', pf') of the adjusted reference positive curve (Rp') from the partial curve between two points (ni'', nf'') of the adjusted reference negative curve (Rn'') to generate a comparative whole-cell curve (U).

[0186] The curve determination unit 110 may calculate an error (curve error) between the comparison all-monomer curve (U) and the measurement all-monomer curve (M).

[0187] The curve determination unit 110 can map at least two of the adjusted reference positive curve (Rp'), the adjusted reference negative curve (Rn''), the positive electrode participation starting point (pi'), the positive electrode participation end point (pf'), the negative electrode participation starting point (ni''), the negative electrode participation end point (nf''), the first scaling factor, the second scaling factor, the comparison full monomer curve (U) and the curve error, and record them in the storage unit 150.

[0188] Here, the curve determination unit 110 may calculate the positive polarity change rate (ps) of the adjusted reference positive polarity curve (Rp') relative to the reference positive polarity curve (Rp). Additionally, the curve determination unit 110 may calculate the negative polarity change rate (ns) of the adjusted reference negative polarity curve (Rn") relative to the reference negative polarity curve (Rn). For example, the curve determination unit 110 may determine the positive polarity change rate (ps) as the first scaling factor and the negative polarity change rate (ns) as the second scaling factor.

[0189] As described above, the curve determination unit 110 can generate a comparative full-body curve corresponding to each pair of a first scaling factor and a second scaling factor selected from the scaling value range. If there are multiple pairs of first scaling factors and second scaling factors, multiple comparative full-body curves will obviously be generated. The curve determination unit 110 can identify the minimum curve error among the curve errors of the multiple comparative full-body curves and obtain information mapped to the minimum curve error from the storage unit 150.

[0190] The battery diagnosis apparatus 100 according to the present disclosure may be connected to a display device (not shown) to output information of a battery diagnosed as abnormal. The display device may display the information of the battery diagnosed as abnormal.

[0191] The battery diagnosis apparatus 100 according to the present disclosure may be connected to an alarm device (not shown). The alarm device may operate while outputting information of a battery diagnosed as abnormal.

[0192] The battery diagnostic device 100 according to the present disclosure can be applied to a battery management system (BMS). That is, the BMS according to the present disclosure can include the battery diagnostic device 100. In this configuration, at least some components of the battery diagnostic device 100 can be implemented by supplementing or adding functionality to components typically included in a BMS. For example, the curve determination unit 110, load calculation unit 120, condition diagnosis unit 130, resistance calculation unit 140, and storage unit 150 of the battery diagnostic device 100 can be implemented as components of the BMS.

[0193] In addition, the battery diagnostic device 100 according to the present disclosure can be equipped in the battery pack 1. That is, the battery pack 1 according to the present disclosure can include the battery diagnostic device 100 and at least one battery cell. In addition, the battery pack 1 can also include electrical components (relays, fuses) and a housing.

[0194] Figure 12 is a diagram illustrating an exemplary configuration of a battery pack 1 including a battery diagnostic device 100 according to one embodiment of the present disclosure.

[0195] The positive terminal of the battery 10 may be connected to the positive terminal (P+) of the battery pack 1 , and the negative terminal of the battery 10 may be connected to the negative terminal (P−) of the battery pack 1 .

[0196] The measuring unit 20 may be connected to a first sensing line SL1, a second sensing line SL2, and a third sensing line SL3. Specifically, the measuring unit 20 may be connected to the positive terminal of the battery 10 through the first sensing line SL1 and to the negative terminal of the battery 10 through the second sensing line SL2. The measuring unit 20 may measure the voltage of the battery 10 based on the voltage measured at each of the first sensing line SL1 and the second sensing line SL2.

[0197] In addition, the measurement unit 20 can be connected to the current measurement unit A via the third sensing line SL3. For example, the current measurement unit A can be an ammeter or a shunt resistor for measuring the charging current and discharging current of the battery 10. The measurement unit 20 can measure the charging current of the battery 10 via the third sensing line SL3 and calculate the charge capacity. In addition, the measurement unit 20 can measure the discharge current of the battery 10 via the third sensing line SL3 and calculate the discharge capacity.

[0198] The load may be connected at one end to the positive terminal (P+) of the battery pack 1 and at the other end to the negative terminal (P-) of the battery pack 1. Thus, the positive terminal of the battery 10, the positive terminal (P+) of the battery pack 1, the load, the negative terminal (P-) of the battery pack 1, and the negative terminal of the battery 10 may be electrically connected.

[0199] For example, the load may be a charger / discharger, or a motor of an electric vehicle supplied with power by the battery 10 .

[0200] The battery diagnostic apparatus 100 according to one embodiment of the present disclosure may be included in a battery manufacturing system (not shown).

[0201] Here, the battery manufacturing system can be a system applied to the battery manufacturing process. For example, a battery may include an electrode assembly, an outer packaging, and an electrolyte solution. The outer packaging provides a space for accommodating the electrode assembly, and when the electrolyte solution is injected into the space, at least a portion of the electrode assembly can be filled with the electrolyte solution. When the outer packaging is sealed, the battery manufacturing can be completed. Subsequently, the battery can undergo an activation process and a degassing process.

[0202] In addition, the condition of the manufactured battery can be diagnosed by the battery diagnostic apparatus 100. Preferably, the condition of the target battery can be diagnosed based on the resistance distribution and the negative electrode load distribution of a plurality of reference batteries manufactured through the same process.

[0203] The battery manufacturing system according to one embodiment of the present disclosure may diagnose whether a manufactured battery is in a normal condition or an abnormal condition by diagnosing whether at least one of an active material, a binder, and a conductive material is included in a large amount in a negative electrode of the manufactured battery.

[0204] Figure 13 FIG. 1 is a flowchart exemplarily illustrating a battery diagnosis method according to an embodiment of the present disclosure.

[0205] Preferably, each step of the battery diagnosis method can be performed by the battery diagnosis apparatus 100. Hereinafter, for the convenience of description, any description shared with the aforementioned description will be omitted or briefly described.

[0206] refer to Figure 13 The battery diagnosis method may include a negative electrode curve determination step S100, a negative electrode load calculation step S200, a comparison step S300, and a condition diagnosis step S400.

[0207] The negative electrode curve determining step S100 is a step in which the curve determining unit 110 determines the negative electrode curve of the battery by adjusting the reference positive electrode curve and the reference negative electrode curve to a measured full-cell curve indicating a corresponding relationship between the capacity and voltage of the battery.

[0208] For example, the curve determination unit 110 may shift or capacity-scale the reference positive electrode curve and the reference negative electrode curve to adapt to the measured full-cell curve.

[0209] The negative electrode load capacity calculation step S200 is a step in which the load capacity calculation unit 120 calculates the negative electrode load capacity of the battery based on the negative electrode curve of the battery.

[0210] For example, the load amount calculation unit 120 may calculate the negative electrode load amount in consideration of the negative electrode change rate, a preset reference negative electrode capacity, and a preset reference area.

[0211] The comparison step S300 is a step in which the condition diagnosis unit 130 compares the resistance of the battery with a preset resistance range and compares the negative electrode load of the battery with a preset load range.

[0212] For example, when the negative electrode load capacity of the battery is equal to or less than the upper limit and equal to or greater than the lower limit of the load capacity range, the condition diagnosis unit 130 may determine that the negative electrode load capacity of the battery is within the load capacity range.

[0213] On the contrary, when the negative electrode load capacity of the battery is greater than the upper limit or less than the lower limit of the load capacity range, the condition diagnosis unit 130 may determine that the negative electrode load capacity of the battery is not within the load capacity range.

[0214] The condition diagnosis step S400 is a step of diagnosing the condition of the battery by the condition diagnosis unit 130 based on the resistance comparison result and the negative electrode load amount comparison result.

[0215] For example, when the resistance is within the resistance range and the negative electrode load amount is within the load amount range, the condition diagnosis unit 130 may diagnose the condition of the battery as normal.

[0216] On the contrary, when the resistance is not within the resistance range or the negative electrode load amount is not within the load amount range, the condition diagnosis unit 130 may diagnose the condition of the battery as abnormal.

[0217] The embodiments of the present disclosure as described herein are not embodied solely by devices and methods, and can be implemented by a program that executes functions corresponding to the exemplary configurations of the present disclosure or a recording medium having the program recorded thereon, and such implementation can be easily implemented by those skilled in the art based on the disclosure of the previously described embodiments.

[0218] Although the present disclosure has been described above with respect to a limited number of embodiments and drawings, it is not limited thereto, and it will be apparent to those skilled in the art that various modifications and changes may be made thereto within the technical aspects of the present disclosure and the scope of the appended claims and their equivalents.

[0219] In addition, since those skilled in the art can make many substitutions, modifications and changes to the present disclosure without departing from the technical aspects of the present disclosure, the present disclosure is not limited to the above-mentioned embodiments and drawings, and some or all of the embodiments can be selectively combined to allow various modifications.

[0220] [List of Reference Signs]

[0221] 100: Battery diagnostic device

[0222] 110: Curve determination unit

[0223] 120: Load calculation unit

[0224] 130: Condition diagnosis unit

[0225] 140: Resistance calculation unit

Claims

1. A battery diagnostic device comprising: a curve determining unit configured to determine a negative electrode curve of the battery by adjusting a reference positive electrode curve and a reference negative electrode curve to fit a measured full-cell curve indicating a corresponding relationship between a capacity and a voltage of the battery; a load capacity calculation unit, configured to calculate a negative electrode load capacity of the battery based on the negative electrode curve of the battery; as well as A condition diagnosis unit is configured to compare the resistance of the battery with a preset resistance range and compare the negative electrode load of the battery with a preset load range, and diagnose the condition of the battery based on the resistance comparison results and the negative electrode load comparison results.

2. The battery diagnostic device according to claim 1, in, The condition diagnosis unit is configured to: The condition of the battery is diagnosed as normal when the resistance is within the resistance range and the negative electrode load is within the load range, and The condition of the battery is diagnosed as abnormal when the resistance is outside the resistance range or the negative electrode load amount is outside the load amount range.

3. The battery diagnostic device according to claim 2, in, The abnormal condition is a condition in which at least one of an active material, a binder, or a conductive material is included in a large amount in the negative electrode of the battery.

4. The battery diagnostic device according to claim 1, in, The load calculation unit is configured to: The negative electrode loading amount is calculated by considering a negative electrode change rate of the negative electrode curve of the battery relative to the reference negative electrode curve.

5. The battery diagnostic device according to claim 4, in, The load calculation unit is configured to: The negative electrode loading amount is calculated by considering the negative electrode change rate, a preset reference negative electrode capacity, and a preset reference area.

6. The battery diagnostic device according to claim 5, in, The load calculation unit is configured to: The negative electrode loading amount indicating the negative electrode capacity per unit area is calculated by multiplying the reference negative electrode capacity by the negative electrode change rate and dividing the product by the reference area.

7. The battery diagnostic device according to claim 1, in, The resistance range is a range set based on the resistance distribution of a plurality of reference batteries, and The load range is a range set based on the negative electrode load distribution of the plurality of reference batteries.

8. The battery diagnostic device according to claim 1, further comprising: A resistance calculation unit is configured to calculate the resistance of the battery based on the measured full-cell curve. 9 . A battery manufacturing system comprising the battery diagnosis device according to claim 1 . 10 . A battery pack comprising the battery diagnostic device according to claim 1 .

11. A battery diagnosis method, comprising: a negative electrode curve determining step, wherein the negative electrode curve determining step determines the negative electrode curve of the battery by adjusting a reference positive electrode curve and a reference negative electrode curve to fit a measured full-cell curve indicating a corresponding relationship between a capacity and a voltage of the battery; a negative electrode loading capacity calculation step, wherein the negative electrode loading capacity calculation step calculates the negative electrode loading capacity of the battery based on the negative electrode curve of the battery; a comparing step of comparing the resistance of the battery with a preset resistance range and comparing the negative electrode load of the battery with a preset load range; as well as A condition diagnosing step of diagnosing a condition of the battery based on the resistance comparison result and the negative electrode load amount comparison result of the comparing step.

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