Battery diagnosis device and battery diagnosis method

Abstract

A battery diagnosis device according to an embodiment disclosed in the present document comprises: a memory for storing one or more instructions; and at least one processor, wherein the one or more instructions, when executed by the at least one processor, are configured to: obtain capacity data and differential capacity data related to a battery cell; identify a first peak and a second peak on the basis of the differential capacity data; identify a capacity range including a state of charge (SOC) corresponding to each of the first peak and the second peak on the basis of the capacity data; and estimate a positive electrode capacity loss of the battery cell on the basis of the capacity range.

Description

Battery diagnostic device and battery diagnostic method

[0001] Cross-citation with related applications

[0002] This invention claims the benefit of priority from Korean Patent Application No. 10-2024-0119261, filed on September 3, 2024, the entire disclosure of which is incorporated herein by reference.

[0003] Technology field

[0004] The embodiments disclosed in this document relate to a battery diagnostic device and a battery diagnostic method.

[0005] In a battery management system (BMS), the current integration method can be used to estimate the state of health (SOH) of a battery. The current integration method can refer to an algorithm that estimates the SOH by assessing the degree of contraction in the battery's voltage data. However, in the case of batteries containing LFP (lithium iron phosphate), errors may occur in SOH estimation due to the potential flatness of LFP. Therefore, there is a need to develop a method for estimating the degree of battery cell degradation based on the current integration method, independent of the potential flatness of LFP.

[0006] One purpose of the embodiments disclosed in this document is to provide a battery diagnostic device and a battery diagnostic method for diagnosing the degree of degradation of a battery by using a peak value related to a negative electrode material in differential capacity data.

[0007] The technical problems of the embodiments disclosed in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the descriptions below.

[0008] A battery diagnostic device according to an embodiment disclosed in the present document comprises a memory for storing one or more instructions; and at least one processor, wherein the one or more instructions, when executed by the at least one processor, are configured to obtain capacity data and differential capacity data related to a battery cell, identify a first peak and a second peak based on the differential capacity data, identify a capacity range including a state of charge (SOC) corresponding to each of the first peak and the second peak based on the capacity data, and estimate a positive electrode capacity loss of the battery cell based on the capacity range.

[0009] For example, the one or more instructions, when executed by the at least one processor, may be configured to estimate a positive electrode capacity loss of the battery cell using a first SOC corresponding to the first peak, a second SOC corresponding to the second peak, and a current change amount from a first point in time corresponding to the first peak to a second point in time corresponding to the second peak, based on identifying the capacity range.

[0010] For example, the one or more instructions, when executed by the at least one processor, may be configured to estimate a positive electrode capacity loss of the battery cell based on a current accumulation method.

[0011] For example, the one or more instructions, when executed by the at least one processor, may be configured to identify an available lithium loss of the battery cell using a total capacity loss of the battery cell and a positive capacity loss of the battery cell.

[0012] For example, the one or more instructions, when executed by the at least one processor, may be configured to verify a positive electrode capacity loss of the battery cell and an available lithium loss of the battery cell based on cell disassembly analysis.

[0013] For example, the battery cell may include a positive electrode material and a negative electrode material, and the one or more instructions, when executed by the at least one processor, may be configured to identify the first peak and the second peak generated based on the negative electrode material among the positive electrode material and the negative electrode material.

[0014] For example, the cathode material may include LFP (Lithium Iron Phosphate).

[0015] For example, the capacity data may represent the capacity of the battery cell relative to the voltage of the battery cell, and the differential capacity data may represent a change in the capacity of the battery cell relative to a change in the voltage of the battery cell.

[0016] A battery diagnosis method according to an embodiment disclosed in the present document may include an operation of acquiring capacity data and differential capacity data related to a battery cell, an operation of identifying a first peak and a second peak based on the differential capacity data, an operation of identifying a capacity range including a state of charge (SOC) corresponding to each of the first peak and the second peak based on the capacity data, and an operation of estimating a positive electrode capacity loss of the battery cell based on the capacity range.

[0017] For example, the operation of estimating the positive electrode capacity loss of the battery cell may include an operation of estimating the positive electrode capacity loss of the battery cell using a first SOC corresponding to the first peak, a second SOC corresponding to the second peak, and a current change amount from a first point in time corresponding to the first peak to a second point in time corresponding to the second peak, based on the capacity range identified.

[0018] For example, the operation of estimating the positive electrode capacity loss of the battery cell may include the operation of estimating the positive electrode capacity loss of the battery cell based on a current integration method.

[0019] For example, the operation of estimating the positive electrode capacity loss of the battery cell may further include the operation of identifying the available lithium loss of the battery cell using the total capacity loss of the battery cell and the positive electrode capacity loss of the battery cell.

[0020] For example, the operation of identifying the available lithium loss of the battery cell may further include the operation of verifying the positive electrode capacity loss of the battery cell and the available lithium loss of the battery cell based on cell disassembly analysis.

[0021] For example, the battery cell includes a positive electrode material and a negative electrode material, and the operation of identifying the first peak and the second peak may include an operation of identifying the first peak and the second peak generated based on the negative electrode material among the positive electrode material and the negative electrode material.

[0022] For example, the cathode material may include LFP (Lithium Iron Phosphate).

[0023] The battery diagnostic device and battery diagnostic method according to the embodiments disclosed in this document can diagnose the degree of degradation of a battery by using a peak value related to a negative electrode material in differential capacity data.

[0024] In addition, various effects may be provided, either directly or indirectly, through this document.

[0025] FIG. 1 is a block diagram showing a battery pack according to one embodiment disclosed in this document.

[0026] FIG. 2 is a block diagram showing the configuration of a battery diagnostic device according to one embodiment disclosed in this document.

[0027] FIG. 3a illustrates an example of a graph showing voltage versus capacity of a battery cell according to one embodiment disclosed in the present document.

[0028] FIG. 3b illustrates an example of a graph showing voltage versus capacity of a cathode material included in a battery cell according to one embodiment disclosed in the present document.

[0029] FIG. 4a illustrates an example of a graph showing capacity change with respect to voltage change of a battery cell according to one embodiment disclosed in the present document.

[0030] FIG. 4b illustrates an example of a graph showing a change in capacity with respect to a change in voltage of a negative electrode material included in a battery cell according to an embodiment disclosed in the present document.

[0031] FIG. 5 illustrates an example of a graph showing voltage changes with respect to capacity changes of a battery cell according to one embodiment disclosed in this document.

[0032] FIG. 6 illustrates an example of a graph representing voltage versus state of charge (SOC) of a battery cell according to one embodiment disclosed in the present document.

[0033] FIG. 7 illustrates an example of a flowchart showing operations performed by a battery diagnostic device according to an embodiment disclosed in this document.

[0034] FIG. 8 shows a computing system executing a battery diagnosis method according to an embodiment disclosed in this document.

[0035] Hereinafter, some embodiments disclosed in this document are described with reference to the accompanying drawings, which illustrate various embodiments of this document. However, this is not intended to limit the present technology to specific embodiments, and it should be understood that various modifications, equivalents, and / or alternatives of the embodiments of this technology are included.

[0036] When assigning reference numerals to components in each drawing, it should be noted that identical components are assigned the same numerals whenever possible, even if they are shown in different drawings. Furthermore, when describing various embodiments disclosed in this document, if a detailed description of a related known configuration or function is deemed to hinder understanding of the embodiments of the present invention, the detailed description will be omitted. The singular form of a noun corresponding to an item may include one or more items, unless the context clearly indicates otherwise.

[0037] In describing the components of the embodiments of this document, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only intended to distinguish the components from other components, and the nature, order, or sequence of the components may not be limited by the terms. In addition, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiments disclosed in this document belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined in this application.

[0038] In addition, in the present disclosure, expressions such as "more than" or "less than" may be used to determine whether a specific condition is satisfied or fulfilled. However, this is merely a description for expressing an example and does not exclude descriptions such as "more than" or "less than." Conditions described as "more than" may be replaced with "more than," conditions described as "less than," and conditions described as "more than and less than" may be replaced with "more than and less than." In addition, hereinafter, "A" to "B" mean at least one of the elements from A (including A) to B (including B).

[0039] In this document, each of the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" may include any one of the items listed together in that phrase, or all possible combinations thereof.

[0040] In this document, when a component (e.g., a first component) is referred to as being “connected,” “coupled,” or “connected,” with or without the terms “functionally” or “communicatively,” or is referred to as being “coupled” or “connected,” it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0041] According to one embodiment, the method according to the various embodiments disclosed in the present document may be provided as included in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or may be distributed online (e.g., downloaded or uploaded) through an application store or directly between two user devices. In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily generated in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

[0042] According to various embodiments, each component (e.g., a module or a program) of the described components may include one or more entities, and some of the entities may be separated and placed in other components. According to various embodiments, one or more components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (e.g., a module or a program) may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the plurality of components identically or similarly to those performed by the corresponding component among the plurality of components prior to integration. According to various embodiments, the operations performed by a module, program, or other component may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

[0043]

[0044] FIG. 1 is a block diagram showing a battery pack according to one embodiment disclosed in this document.

[0045] Referring to FIG. 1, a battery control system including a battery pack (1) and an upper controller (2) included in an upper system according to one embodiment disclosed in the present document is schematically illustrated.

[0046] As illustrated in FIG. 1, the battery pack (1) may include a plurality of battery modules (11), a switching unit (14) connected in series to the first terminal side and / or the second terminal side of the plurality of battery modules (11) to control the charge and discharge current flow of the plurality of battery modules (11), and a battery management system (20) that monitors the voltage, current, temperature, etc. of the battery pack (1) to prevent overcharging and overdischarging, etc.

[0047] In this case, the battery pack (1) may be equipped with a plurality of battery modules (11), sensors (12), switching units (14) and / or battery management systems (20). For example, the first terminal may be a (+) terminal of the plurality of battery modules (11), and the second terminal may be a (-) terminal.

[0048] Here, the switching unit (14) is a device for controlling the current flow for charging or discharging of a plurality of battery modules (11), and for example, at least one relay, magnetic contactor, etc. may be used depending on the specifications of the battery pack (1).

[0049] The plurality of battery modules (11) may include one or more battery cells. For example, the plurality of battery modules (11) may include cylindrical batteries. A cylindrical battery refers to a battery in which battery material is packaged in a cylinder shape. Since the plurality of battery modules (11) include cylindrical batteries, if lithium precipitation occurs inside the cylindrical batteries during constant voltage charging of the plurality of battery modules (11), a phenomenon in which the current flowing through the plurality of battery modules (11) increases may occur.

[0050] The battery management system (20) is an interface for receiving values ​​measured from the various parameters described above, and may include a plurality of terminals and a circuit connected to these terminals to process the values ​​received. In addition, the battery management system (20) may control the ON / OFF of a switching unit (14), for example, a relay or a contactor, and may be connected to a battery cell (11) to monitor the status of each of a plurality of battery modules (11).

[0051] The upper controller (2) can transmit control signals for multiple battery modules (11) to the battery management system (20). Accordingly, the battery management system (20) can be controlled for operation based on signals received from the upper controller (2).

[0052] According to an embodiment, the battery management system (20) may include the battery diagnostic device (100) of FIG. 2. According to another embodiment, the battery management system (20) may be a different system from the battery diagnostic device (100) of FIG. 2. That is, the battery diagnostic device (100) of FIG. 2 may be included in the battery pack (1) or may be configured as another device external to the battery pack (1). For convenience of explanation, it is assumed that the battery diagnostic device (100) is configured as another device external to the battery pack (1).

[0053]

[0054] FIG. 2 is a block diagram showing the configuration of a battery diagnostic device according to one embodiment disclosed in this document.

[0055] A battery diagnostic device (100) according to an embodiment may include at least one of a processor (110), a memory (120), and an interface (130). The processor (110), the memory (120), and the interface (130) may be electrically and / or operably coupled with each other by an electronic component including a communication bus. Hereinafter, the hardwares being operably coupled may mean that a direct connection or an indirect connection is established between the hardwares, either wired or wireless, so that a second hardware is controlled by a first hardware among the hardwares. Although illustrated based on different blocks, the embodiment is not limited thereto, and a portion of the hardwares of FIG. 1 (e.g., at least a portion of the processor (110), the memory (120), and the communication circuit (not shown)) may be included in a single integrated circuit such as a system on a chip (SoC). Communication methods between components may include buses, general purpose input and output (GPIO), serial peripheral interface (SPI), and mobile industry processor interface (MIPI).

[0056] A processor (110) of a battery diagnostic device (100) according to an embodiment may include a hardware component for processing data based on one or more instructions. The hardware component for processing data may include, for example, an arithmetic and logic unit (ALU), a floating point unit (FPU), a field programmable gate array (FPGA), a central processing unit (CPU), a micro controller unit (MCU), and / or an application processor (AP). The number of processors (110) may be one or more. For example, the processor (110) may have a multi-core processor structure including a dual core, a quad core, a hexa core, or an octa core.

[0057] The memory (120) of the battery diagnostic device (100) according to one embodiment may include a hardware component for storing data and / or instructions input and / or output to the processor (110). The memory (120) may include, for example, a volatile memory such as a random-access memory (RAM) and / or a non-volatile memory such as a read-only memory (ROM). For example, the volatile memory may include at least one of a dynamic RAM (DRAM), a static RAM (SRAM), a cache RAM, and a pseudo SRAM (PSRAM). For example, the non-volatile memory may include at least one of a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), a flash memory, a hard disk, a compact disc, and an embedded multi media card (eMMC).

[0058] An interface (130) of a battery diagnostic device (100) according to one embodiment may be configured to generate various battery measurement values ​​from the battery. To this end, the interface (130) may include a measuring means such as a voltmeter, ammeter, or thermometer, and a communication circuit for establishing a communication link with an external device.

[0059] For example, the interface (130) may be configured to collect battery data from the battery. The battery data may include capacity data and differential capacity data.

[0060] For example, capacity data may include data representing voltage relative to the capacity of a battery cell and / or data representing capacity relative to the voltage of the battery cell. For example, capacity data may represent voltage relative to the state of charge (SOC) of a battery cell.

[0061] For example, differential capacity data may include data representing a change in capacity of a battery cell relative to a change in voltage of the battery cell and / or data representing a change in voltage relative to a change in capacity of the battery cell.

[0062] For example, a test voltage or current may be applied to the battery by a charger or discharger, and the interface (130) may measure the response of the battery according to the test voltage.

[0063] According to one embodiment, a processor (110) can obtain capacity data and differential capacity data related to a battery cell (at least one of the battery cells included in a plurality of battery modules (11) of FIG. 1) through an interface (130).

[0064] For example, the capacity data and the differential capacity data may represent data for the entire battery cell. The capacity data and the differential capacity data may represent data for at least one material contained in the battery cell.

[0065] For example, a battery cell may include a positive electrode material and a negative electrode material. The positive electrode material may include Lithium Iron Phosphate (LFP). The negative electrode material may include graphite.

[0066] According to one embodiment, the processor (110) can identify the first peak and the second peak based on the differential capacity data. For example, the processor (110) can identify the first peak and the second peak generated based on the negative electrode material among the positive electrode material and the negative electrode material.

[0067] For example, the first peak and the second peak may be related to the negative electrode material of the battery cell. The first peak and the second peak may be generated based on the electrochemical properties of the negative electrode material. For example, the first peak and the second peak may represent local extrema included in the differential capacity data. For example, the value representing the slope of the differential capacity data based on the first peak may change from a positive number to a negative number. However, this is not limited thereto.

[0068] According to one embodiment, the processor (110) may identify a state of charge (SOC) corresponding to each of the first peak and the second peak based on the capacity data. For example, the processor (110) may identify a capacity range including the SOC. The processor (110) may estimate a positive electrode capacity loss of the battery cell based on the capacity range. The positive electrode capacity loss may be referred to as a positive electrode capacity loss rate in the sense that it represents the amount of positive electrode capacity lost from the positive electrode capacity in the battery cell in the BOL state.

[0069] According to one embodiment, the processor (110) may estimate the anode capacity loss based on a current integration method. For example, the current integration method may be an example of an algorithm for estimating the SOH or anode capacity loss of a battery cell.

[0070] For example, the processor (110) can estimate the positive electrode capacity loss of the battery cell based on the capacity range identified, using the first SOC corresponding to the first peak, the second SOC corresponding to the second peak, and the amount of current change from the first point in time corresponding to the first peak to the second point in time corresponding to the second peak.

[0071] For example, anode capacity loss can refer to a phenomenon in which the overall capacity of a battery cell is lost due to changes occurring at the anode of the battery cell. Anode capacity loss can occur due to changes in the crystal structure of the anode active material in the battery cell. Anode capacity loss can also occur due to chemical reactions between the anode material and the electrolyte.

[0072] For example, the overall capacity loss of a battery cell may include anode capacity loss and available lithium loss. Available lithium loss may indicate a decrease in the amount of lithium ions available to participate in electrochemical reactions within the battery cell.

[0073] For example, the processor (110) may estimate available lithium loss, which represents the amount of lithium ions reduced within the battery cell, based on an estimate of cathode capacity loss, which represents the amount of cathode capacity lost.

[0074] According to one embodiment, a processor (110) can verify anode capacity loss and available lithium loss based on cell disassembly analysis. Cell disassembly analysis may refer to a method of physically disassembling a battery cell to assess (or identify) the condition of internal components.

[0075] The battery diagnosis device (100) according to one embodiment described above can set a capacity range for identifying a positive electrode capacity loss of a battery cell based on a current integration method. The battery diagnosis device (100) can set the capacity range using a peak related to a negative electrode material. The battery diagnosis device (100) can identify a positive electrode capacity loss and available lithium loss of a battery cell based on the set capacity range. The battery diagnosis device (100) can diagnose the condition of the battery cell based on the identification of the positive electrode capacity loss and available lithium loss. The battery diagnosis device (100) can identify the degree of degradation of the battery cell based on the identification of the positive electrode capacity loss and available lithium loss. By setting the capacity range, the battery diagnosis device (100) can improve the accuracy (or reliability) of the degree of degradation of the battery cell.

[0076]

[0077] FIG. 3A illustrates an example of a graph showing voltage versus capacity of a battery cell according to an embodiment disclosed in the present document. FIG. 3B illustrates an example of a graph showing voltage versus capacity of a cathode material included in a battery cell according to an embodiment disclosed in the present document. The battery diagnostic device (100) of FIGS. 3A and 3B may be referenced to the battery diagnostic device (100) of FIG. 2.

[0078] Referring to FIG. 3A, a graph (300) may represent capacity data representing the voltage of a battery cell relative to the capacity of the battery cell obtained by a battery diagnostic device (100) according to an embodiment. The graph (300) may include charge capacity data (301) and discharge capacity data (302). The charge capacity data (301) may represent a charge profile obtained while charging a battery cell. The discharge capacity data (302) may represent a discharge profile obtained while discharging a battery cell.

[0079] Referring to graph (300), a battery diagnostic device (100) according to one embodiment may not include a peak representing the characteristics of a cathode material in capacity data including LFP. The capacity data may have a form similar to the capacity data of a cathode material including LFP.

[0080] Referring to FIG. 3B, an example of a graph (310) representing the characteristics of an LFP is illustrated. The graph (310) may represent capacity data representing the voltage versus capacity of a battery including an LFP. The graph (310) may include charge capacity data (311) and discharge capacity data (312). The charge capacity data (311) may represent a charge profile obtained while charging an LFP, and the discharge capacity data (312) may represent a discharge profile obtained while discharging an LFP.

[0081] Referring to graph (310), charge capacity data (311) and discharge capacity data (312) may exhibit flattening characteristics within a specified range. The specified range may refer to a potential flattening curve. The specified range may represent a capacity range corresponding to a specified potential (e.g., 3.4 V). Since LFP has flattening characteristics within the specified range, referring to graph (300) of FIG. 3A, capacity data of a battery cell having a cathode material including LFP may not have a peak.

[0082] In an embodiment, a battery diagnostic device (100) can identify a peak using differential capacity data when it cannot identify a peak in capacity data. Hereinafter, with reference to FIGS. 4A and 4B, the battery diagnostic device (100) will be described in more detail below with respect to the operation of setting a capacity range for identifying anode capacity loss based on a current integration method using differential capacity data.

[0083]

[0084] FIG. 4A illustrates an example of a graph showing a change in capacity with respect to a change in voltage of a battery cell according to an embodiment disclosed in the present document. FIG. 4B illustrates an example of a graph showing a change in capacity with respect to a change in voltage of a negative electrode material included in a battery cell according to an embodiment disclosed in the present document. The battery diagnostic device (100) of FIGS. 4A and 4B may be referenced to the battery diagnostic device (100) of FIG. 2.

[0085] Referring to FIG. 4a, the graph (400) may represent differential capacity data indicating capacity changes in response to voltage changes of a battery cell. The differential capacity data may be obtained based on the characteristics of the negative electrode material among the positive electrode material including LFP and the negative electrode material including graphite.

[0086] Referring to FIG. 4B, graph (410) may represent differential capacity data based on a negative electrode material including graphite. Referring to graphs (400) and (410), the form of differential capacity data of a battery cell may be similar to the form of differential capacity data based on a negative electrode material. That is, in the differential capacity data of a battery cell, the battery diagnostic device (100) may identify a characteristic peak generated by the negative electrode material.

[0087] Hereinafter, with reference to FIGS. 5 and 6, the operation of the battery diagnostic device (100) to identify a peak will be described.

[0088]

[0089] FIG. 5 illustrates an example of a graph representing a voltage change with respect to a capacity change of a battery cell according to an embodiment disclosed in the present document. FIG. 6 illustrates an example of a graph representing a voltage with respect to a state of charge (SOC) of a battery cell according to an embodiment disclosed in the present document. The battery diagnostic device (100) of FIGS. 5 and 6 may be referenced to the battery diagnostic device (100) of FIG. 2. Referring to FIG. 5, the graph (500) may include differential capacity data (or dQ / dV data) (510) representing a voltage change of a battery cell with respect to a capacity change of the battery cell. Referring to FIG. 6, the graph (600) may include voltage data (610) representing a voltage with respect to the SOC of the battery cell.

[0090] In one embodiment, the differential capacity data (510) can identify one or more peaks (511, 512). For example, the battery diagnostic device (100) can identify a first peak (511) and a second peak (512). For example, the battery diagnostic device (100) can identify a first capacity of a battery cell corresponding to the first peak (511) and a second capacity of the battery cell corresponding to the second peak (512). For example, the battery diagnostic device (100) can identify a first SOC corresponding to the first capacity and a second SOC corresponding to the second capacity.

[0091] Referring to FIG. 6, a battery diagnostic device (100) according to one embodiment can identify a first voltage (611) corresponding to a first SOC and a second voltage (612) corresponding to a second SOC in voltage data (610). The first voltage (611) may correspond to a first peak. The second voltage (612) may correspond to a second peak.

[0092] A battery diagnostic device (100) according to one embodiment can identify (or set) a capacity range (615) based on identifying a first voltage (611) and a second voltage (612). The battery diagnostic device (100) can estimate a positive electrode capacity loss of a battery cell according to a current integration method based on identifying the capacity range (615).

[0093] For example, the battery diagnostic device (100) can estimate the positive electrode capacity loss of the battery cell by using the first SOC, the second SOC, and the current change amount from the first point in time corresponding to the first peak to the second point in time corresponding to the second peak based on the capacity range (615) identified.

[0094] A battery diagnostic device (100) according to one embodiment can identify data indicating the total capacity loss of a battery cell based on the estimated positive electrode capacity loss. The battery diagnostic device (100) can identify data indicating the total capacity loss of a battery cell stored in a memory (e.g., the memory (120) of FIG. 2). The battery diagnostic device (100) can obtain data indicating the total capacity loss of a battery cell from an external electronic device.

[0095] A battery diagnostic device (100) according to one embodiment can identify the available lithium loss of a battery cell using the total capacity loss and the anode capacity loss. For example, the total capacity loss can indicate the degree of degradation of a battery cell. The battery diagnostic device (100) can identify the available lithium loss using the difference between the total capacity loss and the anode capacity loss.

[0096] For example, the battery diagnostic device (100) can control the battery based on the identification of the anode capacity loss and the available lithium loss. For example, the battery diagnostic device (100) can adjust the charge amount of the battery cell or the discharge amount of the battery cell based on the anode capacity loss and the available lithium loss. For example, the battery diagnostic device (100) can provide information indicating the anode capacity loss and the available lithium loss to an external device. As an example, the battery diagnostic device (100) can display information indicating the anode capacity loss and the available lithium loss on a display (not shown).

[0097] According to one embodiment, a battery diagnostic device (100) can verify the anode capacity loss and available lithium loss by comparing the identified anode capacity loss and available lithium loss with reference data obtained through cell disassembly analysis. For example, the battery diagnostic device (100) can provide the results of verifying the anode capacity loss and available lithium loss to an external device.

[0098]

[0099] FIG. 7 illustrates an example of a flowchart showing operations performed by a battery diagnostic device according to an embodiment disclosed in this document.

[0100] FIG. 7 is a flowchart illustrating a battery diagnosis method according to an embodiment disclosed in the present document. Hereinafter, it is assumed that the battery diagnosis device (100) of FIG. 2 performs the process of FIG. 7. In addition, it can be understood that the operations described as being performed by the device are controlled by the processor (110) of the battery diagnosis device (100). Each of the operations of FIG. 7 may be performed sequentially, but is not necessarily performed sequentially. For example, the order of each of the operations may be changed, and at least two operations may be performed in parallel. In addition, the operations of the battery diagnosis device (100) below may be performed by an in-vehicle BMS (Battery Management System), as well as various devices such as a server, cloud, charger, or charger / discharger.

[0101] Referring to FIG. 7, in operation S710, a battery diagnostic device according to one embodiment may acquire capacity data and differential capacity data related to a battery cell. The form of the capacity data may reflect the characteristics of a cathode material including LFP. The differential capacity data may reflect the characteristics of a cathode material including graphite.

[0102] Referring to FIG. 7, in operation S720, a battery diagnostic device according to one embodiment can identify a first peak (e.g., the first peak (511) of FIG. 5) and a second peak (e.g., the second peak (512) of FIG. 5) based on differential capacity data.

[0103] Referring to FIG. 7, in operation S730, a battery diagnostic device according to an embodiment may identify a capacity range (e.g., capacity range (615) of FIG. 6) including an SOC corresponding to each of the first peak and the second peak based on capacity data. The capacity range may include a range for obtaining a positive electrode capacity loss of a battery cell based on a current integration method.

[0104] Referring to FIG. 7, in operation S740, a battery diagnostic device according to one embodiment can estimate a positive electrode capacity loss of a battery cell based on a capacity range.

[0105] For example, a battery diagnostic device may obtain the difference between the total capacity loss of a battery cell and the anode capacity loss based on the estimated anode capacity loss of the battery cell. The difference between the total capacity loss and the anode capacity loss may be referred to as the available lithium loss.

[0106] For example, the battery diagnostic device may control at least one of the charging or discharging of the battery if at least one of the anode capacity loss and the available lithium loss exceeds a specified threshold. For example, the battery diagnostic device may control the charging rate of the battery cell. For example, the battery diagnostic device may control the charging (or discharging) amount of the battery cell. However, this is not limited to these examples.

[0107]

[0108] FIG. 8 shows a computing system executing a battery diagnosis method according to an embodiment disclosed in this document.

[0109] Referring to FIG. 8, a computing system (1000) according to an embodiment disclosed in the present document may include an MCU (1010), a memory (1020), an input / output I / F (1030), and a communication I / F (1040).

[0110] The MCU (1010) may be a processor that executes various programs stored in the memory (1020) (e.g., an SOH calculation program, a cell balancing target determination program, etc.), processes various data including the SOC (state of charge) and SOH (state of health) of multiple battery cells through these programs, and performs the functions of the battery diagnosis device (100) described with reference to FIGS. 2 to 6. The MCU (1010) may be a BMS, a separate PC, or a cloud, but is not limited thereto.

[0111] The memory (1020) can store various programs related to calculating the SOH of a battery cell and determining whether to perform cell balancing. In addition, the memory (1020) can store various data, such as SOC data and SOH data for each battery cell.

[0112] Such memories (1020) may be provided in multiple numbers as needed. The memories (1020) may be volatile memories or non-volatile memories. As volatile memories (1020), RAM, DRAM, SRAM, etc. may be used. As non-volatile memories (1020), ROM, PROM, EAROM, EPROM, EEPROM, flash memories, etc. may be used. The examples of the memories (1020) listed above are merely examples and are not limited to these examples.

[0113] The input / output I / F (1030) can provide an interface that enables data transmission and reception between an input device (not shown) such as a keyboard, mouse, or touch panel, and an output device (not shown) such as a display and the MCU (1010).

[0114] The communication I / F (1040) is a component capable of transmitting and receiving various data with a server, and may be any device capable of supporting wired or wireless communication. For example, programs for calculating the SOH of battery cells or determining balancing targets, as well as various data, can be transmitted and received from a separately provided external server via the communication I / F (1040).

[0115] In this way, the battery diagnosis method according to one embodiment disclosed in this document can be recorded in the memory (1020) and executed by the MCU (1010).

[0116] In the above, although all components constituting the embodiments disclosed in this document have been described as being combined or operating in combination as one, the embodiments disclosed in this document are not necessarily limited to such embodiments. That is, within the scope of the purpose of the embodiments disclosed in this document, all of the components may be selectively combined and operated one or more times.

[0117] In addition, terms such as "include," "comprise," or "have" described above, unless specifically stated to the contrary, should be interpreted to imply the inclusion of the corresponding component, and thus should not be interpreted to exclude other components, but rather to include other components. All terms, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiments disclosed in this document belong, unless otherwise defined. Commonly used terms, such as terms defined in a dictionary, should be interpreted to be consistent with the contextual meaning of the relevant technology, and shall not be interpreted in an idealized or overly formal sense, unless explicitly defined in this document.

[0118] The above description is merely an illustrative description of the technical ideas disclosed in this document, and those skilled in the art to which the embodiments disclosed in this document pertain may make various modifications and variations without departing from the essential characteristics of the embodiments disclosed in this document. Therefore, the embodiments disclosed in this document are not intended to limit the technical ideas of the embodiments disclosed in this document, but to explain them, and the scope of the technical ideas disclosed in this document is not limited by these embodiments. The scope of protection of the technical ideas disclosed in this document should be interpreted by the claims below, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of rights of this document.

Claims

1. Memory for storing one or more instructions; and Contains at least one processor, When said one or more instructions are executed by said at least one processor, Obtain capacity data and differential capacity data related to battery cells, Based on the above differential capacity data, the first peak and the second peak are identified, Based on the above capacity data, a capacity range including a state of charge (SOC) corresponding to each of the first peak and the second peak is identified, configured to estimate the positive electrode capacity loss of the battery cell based on the above capacity range, Battery diagnostic device.

2. In paragraph 1, The one or more instructions, when executed by the at least one processor, Based on the identification of the above capacity range, the battery cell is configured to estimate the positive electrode capacity loss using the first SOC corresponding to the first peak, the second SOC corresponding to the second peak, and the amount of current change from the first point in time corresponding to the first peak to the second point in time corresponding to the second peak. Battery diagnostic device.

3. In paragraph 1, The one or more instructions, when executed by the at least one processor, Based on the current integration method, configured to estimate the positive electrode capacity loss of the battery cell, Battery diagnostic device.

4. In paragraph 1, The one or more instructions, when executed by the at least one processor, configured to identify the available lithium loss of the battery cell by using the total capacity loss of the battery cell and the anode capacity loss of the battery cell, Battery diagnostic device.

5. In paragraph 4, The one or more instructions, when executed by the at least one processor, Based on cell disassembly analysis, configured to verify the anode capacity loss of the battery cell and the available lithium loss of the battery cell, Battery diagnostic device.

6. In paragraph 1, The above battery cell includes a positive electrode material and a negative electrode material, and The one or more instructions, when executed by the at least one processor, Configured to identify the first peak and the second peak generated based on the negative electrode material among the positive electrode material and the negative electrode material, Battery diagnostic device.

7. In paragraph 6, The above cathode material is, Containing LFP (Lithium Iron Phosphate), Battery diagnostic device.

8. In paragraph 1, The above capacity data is, Indicates the capacity of the battery cell compared to the voltage of the battery cell, The above differential capacity data is, Indicates the change in capacity of the battery cell relative to the change in voltage of the battery cell, Battery diagnostic device.

9. Operation for obtaining capacity data and differential capacity data related to battery cells; An operation of identifying a first peak and a second peak based on the above differential capacity data; An operation of identifying a capacity range including a state of charge (SOC) corresponding to each of the first peak and the second peak based on the capacity data, and An operation for estimating a positive electrode capacity loss of the battery cell based on the above capacity range, How to diagnose a battery.

10. In paragraph 9, The operation of estimating the positive electrode capacity loss of the above battery cell is as follows: Based on the identification of the capacity range, an operation of estimating the positive electrode capacity loss of the battery cell using a first SOC corresponding to the first peak, a second SOC corresponding to the second peak, and a current change amount from a first point in time corresponding to the first peak to a second point in time corresponding to the second peak is included. How to diagnose a battery.

11. In paragraph 9, The operation of estimating the positive electrode capacity loss of the above battery cell is as follows: An operation for estimating the positive electrode capacity loss of the battery cell based on the current integration method, How to diagnose a battery.

12. In paragraph 9, The operation of estimating the positive electrode capacity loss of the above battery cell is as follows: Further comprising an operation of identifying the available lithium loss of the battery cell by using the total capacity loss of the battery cell and the positive electrode capacity loss of the battery cell. How to diagnose a battery.

13. In paragraph 12, The operation of identifying the available lithium loss of the above battery cell is: Further comprising an operation of verifying the positive electrode capacity loss of the battery cell and the available lithium loss of the battery cell based on the cell disassembly analysis. How to diagnose a battery.

14. In paragraph 9, The above battery cell includes a positive electrode material and a negative electrode material, and The operation of identifying the first peak and the second peak is as follows: An operation of identifying the first peak and the second peak generated based on the negative electrode material among the positive electrode material and the negative electrode material, How to diagnose a battery.

15. In paragraph 9, The above cathode material is, Containing LFP (Lithium Iron Phosphate), How to diagnose a battery.

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