Battery diagnostic device and method

Abstract

A battery diagnostic device according to an embodiment of the present invention includes a discharge unit electrically connected to a battery and configured to discharge the battery; an X-ray diffraction analysis unit configured to output X-rays toward a plurality of negative electrode tabs included in the battery and generate a graphite profile for each of the plurality of negative electrode tabs based on the output X-rays; and a control unit configured to determine a charge / discharge behavior of each of the plurality of negative electrode tabs based on the generated graphite profiles, and to diagnose a state of the battery based on the determined charge / discharge behaviors.

Description

[Technical field]

[0001] This application claims priority to Korean Patent Application No. 10-2022-0066560, filed on May 31, 2022, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings.

[0002] The present invention relates to a battery diagnostic device and method, and more particularly to a battery diagnostic device and method capable of diagnosing an internal tab break. [Background technology]

[0003] In recent years, as the demand for portable electronic products such as notebooks, video cameras, and mobile phones has grown rapidly and the development of electric vehicles, energy storage batteries, robots, and artificial satellites has progressed in earnest, research into high-performance batteries that can be repeatedly charged and discharged is being actively conducted.

[0004] Currently commercially available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium batteries. Among them, lithium batteries are attracting attention due to their advantages of being able to be freely charged and discharged since they have almost no memory effect compared to nickel-based batteries, as well as their extremely low self-discharge rate and high energy density.

[0005] In general, a battery has a structure in which a positive electrode material, a separator, and a negative electrode material are stacked in parallel. Here, a positive electrode tab is connected to each of the plurality of positive electrode materials, and the plurality of positive electrode tabs may be electrically connected to each other through a positive electrode lead. Similarly, a negative electrode tab is connected to each of the plurality of negative electrode materials, and the plurality of negative electrode tabs may be electrically connected to each other through a negative electrode lead.

[0006] However, there is a high possibility that the electrode tabs (positive and negative electrode tabs) of the battery will break. The positive and negative electrode tabs, like the positive and negative electrode plates, are made of very thin metal films, so if the secondary battery is subjected to an impact, there is a high probability that they will break before other components.

[0007] If at least one positive electrode tab or at least one negative electrode tab is damaged and disconnected, the performance of the battery may be reduced and may lead to accidents such as fire or explosion. Therefore, there is a need to develop a technology that can accurately diagnose disconnection of the internal tabs of a battery. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made to solve the above problems, and an object of the present invention is to provide a battery diagnostic apparatus and method capable of accurately diagnosing disconnection of an inner tab of a battery.

[0009] Other objects and advantages of the present invention can be understood from the following description and will become more apparent from the embodiments of the present invention. Also, the objects and advantages of the present invention can be realized by the means and combinations thereof as set forth in the claims. [Means for solving the problem]

[0010] A battery diagnostic device according to one aspect of the present invention includes a discharge unit electrically connected to a battery and configured to discharge the battery; an X-ray diffraction analysis unit configured to output X-rays toward a plurality of negative electrode tabs included in the battery and generate a graphite profile for each of the plurality of negative electrode tabs based on the output X-rays; and a control unit configured to determine charge / discharge behaviors of each of the plurality of negative electrode tabs based on the generated graphite profiles, and to diagnose a state of the battery based on the determined charge / discharge behaviors.

[0011] The control unit may be configured to determine the charge / discharge behavior of each of the plurality of negative electrode tabs as a charge behavior or a discharge behavior by checking the integrated intensity of graphite in each of the plurality of negative electrode tabs based on the plurality of graphite profiles.

[0012] The control unit may be configured to determine the charge / discharge behavior of the negative electrode tab in which the integral intensity decreases as the discharge behavior, and to determine the charge / discharge behavior of the negative electrode tab in which the integral intensity increases as the charge behavior.

[0013] The control unit may be configured to diagnose the battery state as normal if the discharge behavior is confirmed in a plurality of the negative electrode tabs.

[0014] The control unit may be configured to diagnose a state of the battery as abnormal if the charging behavior is confirmed in at least one of the plurality of negative electrode tabs.

[0015] The control unit may be configured to diagnose the state of the negative electrode tab for which the charging behavior has been confirmed as being in an open state.

[0016] The X-ray diffraction analysis unit may be configured to output the X-rays in a direction penetrating the negative electrode tabs.

[0017] The X-ray diffraction analysis unit may be configured to output the X-rays in a stacking direction of the multiple negative electrode tabs.

[0018] The X-ray diffraction analysis unit may be configured to determine an integrated intensity of graphite for each of the plurality of negative electrode tabs based on diffraction information of the X-rays each time the X-rays are output, and to generate the graphite profile so as to indicate a correspondence relationship between time and the integrated intensity for each of the plurality of negative electrode tabs.

[0019] A battery testing apparatus according to another aspect of the present invention includes a battery diagnostic apparatus according to an aspect of the present invention.

[0020] A battery diagnosis method according to yet another aspect of the present invention includes a discharging step of discharging a battery; an X-ray output step of outputting X-rays toward a plurality of negative electrode tabs included in the battery; a graphite profile generating step of generating a graphite profile for each of the plurality of negative electrode tabs based on the outputted X-rays; a charge / discharge behavior determining step of determining charge / discharge behaviors of each of the plurality of negative electrode tabs based on the plurality of graphite profiles generated in the graphite profile generating step; and a battery status diagnosing step of diagnosing a status of the battery based on the determined plurality of charge / discharge behaviors. Effect of the Invention

[0021] According to one aspect of the present invention, the state of a battery can be non-destructively diagnosed based on a graphite profile generated through X-ray diffraction analysis.

[0022] Furthermore, according to one aspect of the present invention, it is possible to specifically diagnose disconnection of the negative electrode tab of the battery.

[0023] The effects of the present invention are not limited to the effects described above, 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.

[0024] The following drawings attached to this specification, together with the detailed description of the invention described below, serve to further understand the technical ideas of the present invention, and the present invention should not be interpreted as being limited only to the matters described in the drawings. [Brief description of the drawings]

[0025] [Figure 1] 1 is a diagram illustrating a battery diagnostic device according to an embodiment of the present invention; [Diagram 2] 1 is a schematic diagram of a battery according to an embodiment of the present invention; [Diagram 3] 1 is a diagram illustrating an internal structure of a battery according to an embodiment of the present invention; [Figure 4]1 is a diagram illustrating an internal structure of a battery according to an embodiment of the present invention; [Diagram 5] 1 is a schematic diagram illustrating an example of X-ray irradiation of a battery according to an embodiment of the present invention; [Figure 6] 1 is a schematic diagram illustrating an example of X-ray irradiation of a battery according to an embodiment of the present invention; [Figure 7] FIG. 2 is a schematic diagram illustrating a first graphite profile according to an embodiment of the present invention. [Figure 8] FIG. 2 is a schematic diagram illustrating a second graphite profile according to an embodiment of the present invention. [Figure 9] 1 is a schematic diagram illustrating an internal structure of a battery in which a negative electrode tab is broken according to an embodiment of the present invention; [Figure 10] 11 is a diagram illustrating a battery diagnostic method according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] The terms and words used in this specification and the claims should not be interpreted limited to their ordinary and dictionary meanings, but should be interpreted in a meaning and concept that corresponds to the technical idea of ​​the present invention, based on the principle that the inventor himself can appropriately define the concept of the term in order to explain the invention in the best possible way.

[0027] Therefore, it should be understood that the embodiment described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can be substituted for them at the time of this application.

[0028] In addition, in the description of the present invention, if it is determined that a detailed description of related publicly known structures or functions may make the gist of the present invention unclear, the detailed description will be omitted.

[0029] Terms including ordinal numbers such as first, second, etc. are used to distinguish one of various components from other components, and are not intended to limit the components.

[0030] Throughout the specification, when a part "comprises" a certain element, this does not mean to exclude other elements, but means that it may further include other elements, unless otherwise specified.

[0031] Furthermore, throughout this specification, when a part is referred to as being "connected" to another part, this includes not only a "direct connection" but also an "indirect connection" through other elements.

[0032] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0033] FIG. 1 is a diagram illustrating a battery diagnostic device 100 according to an embodiment of the present invention.

[0034] Referring to FIG. 1, a battery diagnostic device 100 includes a discharge unit 110, an X-ray diffraction analysis unit 120, and a control unit .

[0035] Here, the term "battery" refers to a single independent cell that has a negative terminal and a positive terminal and can be physically separated. As an example, a lithium ion battery or a lithium polymer battery may be considered as a battery.

[0036] FIG. 2 is a diagram illustrating a battery 10 according to an embodiment of the present invention, and FIGS. 3 and 4 are diagrams illustrating an internal structure of the battery 10 according to an embodiment of the present invention.

[0037] 2 to 4, the battery 10 includes a cell assembly in which an anode material 31, a separator 33, and a cathode material 32 are stacked. An anode tab 21 may be connected to the anode material 31, and a cathode tab may be connected to the cathode material 32. The anode tabs 21 may be connected to anode leads 11, and the cathode tabs may be connected to cathode leads 12. Although FIG. 2 shows an embodiment in which the anode lead 11 and the cathode lead 12 are positioned in the same direction, the anode lead 11 and the cathode lead 12 may be positioned in different directions depending on the embodiment.

[0038] The discharge unit 110 may be configured to be electrically connected to the battery 10 .

[0039] Specifically, the discharge unit 110 may be coupled to the negative electrode lead 11 and the positive electrode lead 12 of the battery 10. For example, in the embodiment of FIG.

[0040] The discharge unit 110 may be configured to discharge the battery 10 .

[0041] For example, the discharge unit 110 may receive a discharge start signal and information on a discharge C rate from the control unit 130. Then, the discharge unit 110 may discharge the battery 10 at a discharge C rate corresponding to the received discharge C rate information.

[0042] The X-ray diffraction analysis unit 120 may be configured to output X-rays toward a plurality of negative electrode tabs 21 included in the battery 10.

[0043] Specifically, the X-ray diffraction analysis unit 120 may be configured to irradiate the battery 10 with X-rays and use the diffracted rays to diagnose the state of the battery 10. For example, the X-ray diffraction analysis unit 120 may be configured to be capable of performing X-ray diffraction (XRD) analysis.

[0044] Preferably, the X-ray diffraction analysis unit 120 may periodically output X-rays toward the battery 10. That is, during the process of discharging the battery 10, the X-ray diffraction analysis unit 120 may periodically output X-rays toward the battery 10.

[0045] 5 and 6 are schematic diagrams illustrating an example of X-ray irradiation of a battery 10 according to an embodiment of the present invention.

[0046] 5, the X-ray diffraction analysis unit 120 may output X-rays toward the battery 10. Specifically, in the embodiment of FIG. 6, the X-ray diffraction analysis unit 120 may output X-rays toward a plurality of negative electrode tabs 21 included in the battery 10.

[0047] The X-ray diffraction analysis unit 120 can be configured to generate a graphite profile for each of the multiple negative electrode tabs 21 based on the output X-rays.

[0048] Specifically, the X-ray diffraction analysis unit 120 can be configured to determine the integrated intensity of graphite for each of the multiple negative electrode tabs 21 based on the diffraction information of the X-rays each time the X-rays are output.

[0049] Here, the integrated intensity is a value obtained using X-ray diffraction analysis. The integrated intensity can be determined each time X-rays are output. For example, if X-rays are output 10 times, the determined integrated intensity of graphite can be 10.

[0050] Preferably, the X-ray diffraction analysis unit 120 can determine the integrated intensity of graphite in each of the multiple negative electrode tabs 21 of the battery 10 when the battery 10 is discharging. For example, in the embodiment of Fig. 3, the X-ray diffraction analysis unit 120 can determine the integrated intensity of graphite for each of the multiple negative electrode tabs 21. Because X-rays can penetrate the negative electrode tabs 21, the integrated intensity of graphite for each of the multiple negative electrode tabs 21 can be determined.

[0051] The X-ray diffraction analysis unit 120 can then be configured to generate a graphite profile for each of the multiple negative electrode tabs 21, so as to indicate the relationship between time and integrated intensity.

[0052] Specifically, the X-ray diffraction analysis unit 120 may generate a graphite profile that shows the change in integrated intensity over time. For example, the X-ray diffraction analysis unit 120 may generate a graphite profile that shows the determined integrated intensities over time (in accordance with the order of the X-ray irradiation cycle).

[0053] FIG. 7 is a diagram illustrating a first graphite profile GP1 according to an embodiment of the present invention, and FIG. 8 is a diagram illustrating a second graphite profile GP2 according to an embodiment of the present invention.

[0054] For example, in the first graphite profile GP1, the integral intensity of graphite decreases in a time interval less than 50 minutes, whereas in the second graphite profile GP2, the integral intensity of graphite increases in a time interval less than 50 minutes. That is, in the embodiments of FIG. 7 and FIG. 8, the charge / discharge behavior of the negative electrode tab 21 in a time interval less than 50 minutes may be different.

[0055] 7, the negative electrode tab 21 may be discharging for a time period less than 50 minutes and may be in a resting state for a time period of 50 minutes or more. The first graphite profile GP1 may be a graphite profile for the negative electrode tab 21 discharging for a time period from 0 to 50 minutes.

[0056] 8, the negative electrode tab 21 may be charged for a time period less than 50 minutes and may be in a resting state for a time period of 50 minutes or more. The second graphite profile GP2 may be a graphite profile for the negative electrode tab 21 that is charged for a time period from 0 minutes to 50 minutes.

[0057] The control unit 130 can be configured to determine the charge / discharge behavior of each of the multiple negative electrode tabs 21 based on the multiple generated graphite profiles.

[0058] Specifically, the control unit 130 may confirm the integral intensity of graphite in each of the multiple negative electrode tabs 21 based on the multiple graphite profiles. Then, the control unit 130 may be configured to determine the charge / discharge behavior of each of the multiple negative electrode tabs 21 as a charge behavior or a discharge behavior.

[0059] For example, the control unit 130 can check the increase or decrease in the integrated intensity of the graphite over time from the graphite profile. Then, the control unit 130 can determine the charge / discharge behavior of the corresponding negative electrode tab 21 according to the checked increase or decrease in the integrated intensity.

[0060] Specifically, the control unit 130 may be configured to determine the charge / discharge behavior of the negative electrode tab 21 in which the integral intensity decreases as the discharge behavior. Conversely, the control unit 130 may be configured to determine the charge / discharge behavior of the negative electrode tab 21 in which the integral intensity increases as the charge behavior.

[0061] In the embodiment of Fig. 7, in the time period less than 50 minutes, the integral intensity of the graphite decreases over time. Therefore, the control unit 130 can determine the charge / discharge behavior of the negative electrode tab 21 corresponding to the embodiment of Fig. 7 as the discharge behavior.

[0062] On the other hand, in the embodiment of Fig. 8, in the time period less than 50 minutes, the integrated intensity of the graphite increases over time. Therefore, the control unit 130 can determine the charge / discharge behavior of the negative electrode tab 21 corresponding to the embodiment of Fig. 8 as the charging behavior.

[0063] The control unit 130 may be configured to diagnose the state of the battery 10 based on the determined plurality of charging and discharging behaviors.

[0064] Specifically, the control unit 130 can determine the charge / discharge behavior for each of the multiple negative electrode tabs 21. Then, the control unit 130 can diagnose the state of the battery 10 based on whether the charge / discharge behaviors of the multiple negative electrode tabs 21 match.

[0065] Preferably, the multiple negative electrode tabs 21 included in the battery 10 should have the same charge / discharge behavior. That is, if the charge / discharge behavior of some of the multiple negative electrode tabs 21 included in the battery 10 differs, the state of the battery 10 may be abnormal. Therefore, the control unit 130 may diagnose the state of the battery 10 as normal or abnormal, taking into account the charge / discharge behavior of the multiple negative electrode tabs 21.

[0066] For example, assume that the first graphite profile GP1 according to the embodiment of Fig. 7 and the second graphite profile GP2 according to the embodiment of Fig. 8 are profiles for two negative electrode tabs 21 included in one battery 10. The control unit 130 may diagnose the state of the battery 10 as being abnormal because the charge / discharge behaviors of the two negative electrode tabs 21 included in the battery 10 are different.

[0067] Preferably, the battery 10 diagnosed as being in an abnormal state by the control unit 130 can be disposed of in order to prevent accidents such as fire or explosion.

[0068] The battery diagnostic device 100 according to an embodiment of the present invention can confirm the charging and discharging behavior of a plurality of negative electrode tabs 21 inside a battery using an X-ray diffraction analysis method. Furthermore, the battery diagnostic device 100 can diagnose the state of the battery 10 in consideration of the charging and discharging behavior of the plurality of negative electrode tabs 21. Therefore, the battery diagnostic device 100 has an advantage in that it can accurately diagnose the state of the battery 10 in a non-destructive manner.

[0069] Meanwhile, the control unit 130 of the battery diagnostic device 100 may selectively include a processor, an ASIC (Application-Specific Integrated Circuit), other chipsets, logic circuits, registers, a communication modem, a data processing device, etc., known in the art, to execute various control logics performed in the present invention. Also, when the control logic is embodied as software, the control unit 130 may be embodied as a collection of program modules. In this case, the program modules may be stored in a memory and executed by the control unit 130. The memory may be provided inside or outside the control unit 130, and may be connected to the control unit 130 by various known means.

[0070] The battery diagnostic device 100 may further include a recording unit 140. The recording unit 140 may store data and programs necessary for each component of the battery diagnostic device 100 to operate and function, or data generated in the process of operating and functioning. The recording unit 140 is not particularly limited in type as long as it is a known information recording means known to be capable of recording, erasing, updating and reading data. As an example, the information recording means may include a RAM, a flash memory, a ROM, an EEPROM, a register, etc. The recording unit 140 may also store a program code in which a process executable by the control unit 130 is defined.

[0071] Hereinafter, an embodiment in which the control unit 130 diagnoses the state of the battery 10 while the battery 10 is being discharged will be described in more detail.

[0072] The control unit 130 may be configured to diagnose the state of the battery 10 as normal if a discharging behavior is confirmed in the plurality of negative electrode tabs 21. Conversely, the control unit 130 may be configured to diagnose the state of the battery 10 as abnormal if a charging behavior is confirmed in at least one of the plurality of negative electrode tabs 21.

[0073] Preferably, when the battery 10 is discharging, the negative electrode tabs 21 included in the battery 10 should exhibit a discharging behavior. However, if a defect occurs inside the battery 10, at least one of the negative electrode tabs 21 may exhibit a charging behavior even when the battery 10 is discharging.

[0074] Specifically, the control unit 130 can be configured to diagnose the state of the negative electrode tab 21, in which the charging behavior has been confirmed, as being in a disconnected state.

[0075] FIG. 9 is a diagram illustrating a schematic internal structure of a battery 10 in which a negative electrode tab 21 is broken according to an embodiment of the present invention.

[0076] Referring to FIG. 9, the first negative electrode tab 21a may be connected to the first negative electrode material 31a, and the second negative electrode tab 21b may be connected to the second negative electrode material 31b. The third negative electrode tab 21c may be connected to the third negative electrode material 31c, and the fourth negative electrode tab 21d may be connected to the fourth negative electrode material 31d. In a preferred case, when the battery 10 is discharged, the charge and discharge behaviors of the first negative electrode tab 21a, the second negative electrode tab 21b, the third negative electrode tab 21c, and the fourth negative electrode tab 21d should all be discharging behaviors. However, as in the embodiment of FIG. 9, when the first negative electrode tab 21a is disconnected, the charge and discharge behavior of the first negative electrode tab 21a may be charging behavior even when the battery 10 is discharged. That is, the graphite profile of the first negative electrode tab 21a may correspond to the second graphite profile GP2 in FIG. 8, and the graphite profiles of the second negative electrode tab 21b, the third negative electrode tab 21c, and the fourth negative electrode tab 21d may correspond to the first graphite profile GP1 in FIG.

[0077] In the embodiment of FIG. 9, the second negative electrode material 31b, the third negative electrode material 31c, and the fourth negative electrode material 31d, in which the negative electrode tab 21 is not broken, can be electrically connected to the negative electrode lead 11. That is, when the battery 10 is discharged, lithium ions can be desorbed from the second negative electrode material 31b, the third negative electrode material 31c, and the fourth negative electrode material 31d. Specifically, lithium ions can be desorbed from the graphite layers of the second negative electrode material 31b, the third negative electrode material 31c, and the fourth negative electrode material 31d due to discharge. However, since the first negative electrode tab 21a is broken, lithium ions are not desorbed from the graphite layer of the first negative electrode material 31a. On the contrary, lithium ions desorbed from the graphite layers of the second negative electrode material 31b, the third negative electrode material 31c, and the fourth negative electrode material 31d can move through the electrolyte and be inserted into the graphite layer of the first negative electrode material 31a. Therefore, the depth of charge of the graphite increases in the broken first negative electrode tab 21a even when the battery 10 is discharging. The increase in the depth of charge of the first negative electrode tab 21a can be confirmed by an increase in the integrated intensity of the graphite in the first negative electrode tab 21a.

[0078] The battery diagnostic device 100 according to an embodiment of the present invention can accurately diagnose disconnection of the negative electrode tab 21 of the battery 10 using X-ray diffraction analysis. That is, the battery diagnostic device 100 has an advantage in that it can not only diagnose the state of the battery 10 but also specifically diagnose the cause of the defect in the battery 10.

[0079] On the other hand, the X-ray diffraction analysis unit 120 can be configured to output X-rays in a direction penetrating the multiple negative electrode tabs 21.

[0080] Considering the characteristics of X-rays, the X-rays output from the X-ray diffraction analysis unit 120 may pass through a plurality of negative electrode tabs 21. Then, the X-ray diffraction analysis unit 120 must generate a graphite profile for each of the plurality of negative electrode tabs 21. Therefore, the X-ray diffraction analysis unit 120 may output X-rays in a direction penetrating the plurality of negative electrode tabs 21 to generate a plurality of graphite profiles reflecting the integrated intensity of graphite measured at the same time point.

[0081] 6, the D direction may be a direction that passes through the multiple negative electrode tabs 21. Therefore, the X-ray diffraction analysis unit 120 may output X-rays toward the multiple negative electrode tabs 21 in the D direction.

[0082] In other words, the X-ray diffraction analysis unit 120 may be configured to output X-rays in the stacking direction of the multiple negative electrode tabs 21. In the embodiment of FIG. 6, the multiple negative electrode tabs 21 are electrically connected to one negative electrode lead 11, so that the ends of the multiple negative electrode tabs 21 may be stacked so as to contact each other. Here, the stacking direction of the multiple negative electrode tabs 21 may be the same as the D direction, which is the direction penetrating the multiple negative electrode tabs 21. Therefore, the X-ray diffraction analysis unit 120 may output X-rays toward the multiple negative electrode tabs 21 along the D direction.

[0083] The battery diagnostic device 100 according to an embodiment of the present invention can determine the integral intensities of graphite for a plurality of negative electrode tabs 21 at the same time and generate a plurality of graphite profiles based on the determined integral intensities. Therefore, the accuracy and reliability of the battery state diagnosis result by the battery diagnostic device 100 can be improved.

[0084] A battery testing apparatus according to another embodiment of the present invention includes a battery diagnostic apparatus 100 according to an embodiment of the present invention.

[0085] For example, the battery testing apparatus may further include a fixing unit configured to fix the battery 10. When the battery 10 is fixed to the fixing unit, the discharge unit 110 may be connected to the negative electrode lead 11 and the positive electrode lead 12 of the battery 10. When the discharge unit 110 receives a discharge start signal and information on a discharge C rate from the control unit 130, the discharge unit 110 may discharge the battery 10 at the corresponding C rate. During the discharge process, the X-ray diffraction analysis unit 120 may output X-rays to the battery 10 and generate a graphite profile for each of the plurality of negative electrode tabs 21. The control unit 130 may determine the charge / discharge behavior of each of the plurality of negative electrode tabs 21 in consideration of the plurality of graphite profiles. If the charge / discharge behavior of at least one negative electrode tab 21 is confirmed as a charging behavior, the control unit 130 may diagnose the state of the battery 10 as an abnormal state. In this case, the battery 10 diagnosed as being in an abnormal state may be disposed of as unnecessary.

[0086] FIG. 10 is a diagram illustrating a battery diagnostic method according to another embodiment of the present invention.

[0087] Preferably, each step of the battery diagnostic method may be performed by the battery diagnostic device 100. Hereinafter, for convenience of explanation, contents that overlap with the above explanation will be omitted or briefly explained.

[0088] The battery diagnostic method includes a discharging step S100, an X-ray output step S200, a graphite profile generating step S300, a charge / discharge behavior determining step S400, and a battery state diagnostic step S500.

[0089] The discharging step S100 is a step of discharging the battery 10 and may be performed by the discharging unit 110.

[0090] The X-ray output step S200 is a step of outputting X-rays toward a plurality of negative electrode tabs 21 included in the battery 10, and may be performed by the X-ray diffraction analysis unit 120.

[0091] For example, the X-ray diffraction analysis unit 120 can irradiate X-rays in a direction penetrating the multiple negative electrode tabs 21 included in the battery 10 (the stacking direction of the multiple negative electrode tabs 21).

[0092] The graphite profile generating step S300 is a step of generating a graphite profile for each of the plurality of negative electrode tabs 21 based on the output X-rays, and may be performed by the X-ray diffraction analysis unit 120.

[0093] The X-ray diffraction analysis section 120 can generate a graphite profile that indicates the integrated intensity of graphite as a function of time for each of the multiple negative electrode tabs 21.

[0094] The charge / discharge behavior determining step S400 is a step of determining the charge / discharge behavior of each of the plurality of negative electrode tabs 21 based on the plurality of graphite profiles generated in the graphite profile generating step S300, and may be performed by the control unit 130.

[0095] Specifically, the control unit 130 can determine the charge / discharge behavior of each of the multiple negative electrode tabs 21 based on the increase or decrease in the integrated intensity of graphite that appears in the graphite profile.

[0096] For example, the control unit 130 may determine the charge / discharge behavior of the negative electrode tab 21 in which the integral intensity of the graphite increases over time as the charge behavior. Conversely, the control unit 130 may determine the charge / discharge behavior of the negative electrode tab 21 in which the integral intensity of the graphite decreases over time as the discharge behavior.

[0097] The battery state diagnosis step S500 is a step of diagnosing the state of the battery 10 based on the determined plurality of charging and discharging behaviors, and may be performed by the control unit 130.

[0098] Specifically, when the charge / discharge behavior of at least one of the multiple negative electrode tabs 21 is a charging behavior, the control unit 130 may diagnose the state of the battery 10 as an abnormal state. More specifically, the control unit 130 may diagnose the negative electrode tab 21 whose charge / discharge behavior is a charging behavior as being in a disconnected state.

[0099] As described above, the present invention has been described using limited embodiments and drawings. However, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention belongs within the technical spirit of the present invention and the equivalent scope of the claims.

[0100] Furthermore, the present invention described above is susceptible to various substitutions, modifications and alterations by a person having ordinary knowledge in the technical field to which the present invention belongs, within the scope that does not deviate from the technical concept of the present invention, and is not limited to the above-described embodiments and the accompanying drawings, but may be configured by selectively combining all or part of each embodiment for various modifications. [Explanation of symbols]

[0101] 10: Battery 11: Negative lead 12: Positive lead 21: Negative electrode tab 22: Positive electrode tab 31: Anode material 32: Cathode material 33: Separation membrane 100: Battery diagnostic device 110:Discharge part 120: X-ray diffraction analysis section 130: Control unit 140: Recording section

Claims

1. A discharge unit electrically connected to the battery and configured to discharge the battery; an X-ray diffraction analysis unit configured to output X-rays toward a plurality of negative electrode tabs included in the battery and generate a graphite profile for each of the plurality of negative electrode tabs based on the output X-rays; a control unit configured to determine a charge / discharge behavior of each of the plurality of negative electrode tabs based on the generated plurality of graphite profiles, and to diagnose a state of the battery based on the determined plurality of charge / discharge behaviors.

2. The control unit is 2. The battery diagnostic device according to claim 1, wherein the battery diagnostic device is configured to determine the charge / discharge behavior of each of the plurality of negative electrode tabs as a charge behavior or a discharge behavior by checking an integrated intensity of graphite in each of the plurality of negative electrode tabs based on the plurality of graphite profiles.

3. The control unit is The battery diagnostic device according to claim 2 , configured to determine the charge / discharge behavior of the negative electrode tab in which the integral strength decreases as the discharge behavior, and to determine the charge / discharge behavior of the negative electrode tab in which the integral strength increases as the charge behavior.

4. The control unit is If the discharge behavior is confirmed in a plurality of the negative electrode tabs, the battery is diagnosed as being in a normal state; The battery diagnostic device according to claim 2 , configured to diagnose the state of the battery as an abnormal state if the charging behavior is confirmed in at least one of the plurality of negative electrode tabs.

5. The control unit is The battery diagnostic device according to claim 4 , wherein the device is configured to diagnose the state of the negative electrode tab for which the charging behavior has been confirmed as being in an open-circuit state.

6. The X-ray diffraction analysis unit is The battery diagnostic device according to claim 1 , configured to output the X-rays in a direction penetrating a plurality of the negative electrode tabs.

7. The X-ray diffraction analysis unit is The battery diagnostic device according to claim 1 , configured to output the X-rays in a stacking direction of the plurality of negative electrode tabs.

8. The X-ray diffraction analysis unit is 2. The battery diagnostic device according to claim 1, configured to determine an integrated intensity of graphite for each of the plurality of negative electrode tabs based on diffraction information of the X-rays each time the X-rays are output, and to generate the graphite profile so as to indicate a correspondence relationship between time and the integrated intensity for each of the plurality of negative electrode tabs.

9. A battery testing device comprising the battery diagnostic device according to any one of claims 1 to 8.

10. a discharge phase in which the battery is discharged; an X-ray output step of outputting X-rays toward a plurality of negative electrode tabs included in the battery; generating a graphite profile for each of the plurality of negative electrode tabs based on the output X-rays; determining a charge / discharge behavior of each of the plurality of negative electrode tabs based on the plurality of graphite profiles generated in the graphite profile generating step; and diagnosing a battery state based on the determined plurality of charging and discharging behaviors.

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