Battery diagnostic device and operation method thereof

Abstract

A battery unit diagnostic device according to one embodiment disclosed in this document may include: a data acquisition unit that acquires charge / discharge data while a battery unit is being charged / discharged; the charge / discharge data including charge / discharge profiles acquired while the battery unit is being charged / discharged according to different charge / discharge rates; a profile acquisition unit that acquires a first current-voltage profile based on the charge / discharge profile; a profile calculation unit that calculates a second current-voltage profile according to a specified charge / discharge rate that is different from the different charge / discharge rates based on the first current-voltage profile; and a data calculation unit that calculates capacity-voltage relationship data based on the second current-voltage profile.

Description

[Technical Field]

[0001] The present invention claims the benefit of priority based on Korean Patent Application No. 10-2023-0015193, filed on February 3, 2023, the entire contents of which are incorporated herein by reference. SUMMARY OF THE INVENTION The embodiments disclosed herein relate to a battery diagnostic device and a method of operation thereof. [Background technology]

[0002] In recent years, research and development into secondary batteries has been actively pursued. Here, secondary batteries are batteries that can be charged and discharged, and include both conventional Ni / Cd batteries, Ni / MH batteries, and more recent lithium-ion batteries. Among secondary batteries, lithium-ion batteries have the advantage of having a much higher energy density than conventional Ni / Cd batteries, Ni / MH batteries, and other batteries. Furthermore, because lithium-ion batteries can be manufactured to be compact and lightweight, they are used as power sources for mobile devices. Furthermore, lithium-ion batteries have been expanding their scope of use to include power sources for electric vehicles, and are attracting attention as a next-generation energy storage medium.

[0003] Furthermore, the secondary battery can generally be used as a battery pack including a battery module in which a plurality of battery cells are connected in series and / or parallel, and can also be used as a battery rack including a plurality of battery modules and a rack frame for accommodating such battery modules.

[0004] Such battery cells, battery modules, battery packs, or battery racks can be used in a variety of devices. For example, the batteries can be used in mobile devices such as mobile phones, laptop computers, smartphones, and smart pads, as well as in fields such as electrically powered automobiles (EVs, HEVs, and PHEVs) and large-capacity energy storage systems (ESS).

[0005] Such batteries can be managed and controlled in status and operation by a battery management system (BMS), which can be included with the batteries in a device, or can manage and control the batteries remotely from the device containing the batteries. Summary of the Invention [Problem to be solved by the invention]

[0006] The battery management system can measure various parameters of the battery to diagnose the battery state, but some of the parameters measured to diagnose the battery state (e.g., charge amount) can be affected by overvoltage that occurs during charging and discharging of the battery. A method is needed to reduce the effect of such overvoltage and obtain a precise charge / discharge profile of the battery.

[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 following description. [Means for solving the problem]

[0008] A battery unit diagnostic device according to one embodiment disclosed in this document may include: a data acquisition unit that acquires charge / discharge data while a battery unit is being charged / discharged; the charge / discharge data including charge / discharge profiles acquired while the battery unit is being charged / discharged according to different charge / discharge rates; a profile acquisition unit that acquires a first current-voltage profile based on the charge / discharge profile; a profile calculation unit that calculates a second current-voltage profile according to a specified charge / discharge rate that is different from the different charge / discharge rates based on the first current-voltage profile; and a data calculation unit that calculates capacity-voltage relationship data based on the second current-voltage profile.

[0009] An operating method of a battery unit diagnostic device according to one embodiment disclosed herein may include an operation of acquiring charge / discharge data while a battery unit is being charged / discharged, the charge / discharge data including charge / discharge profiles acquired while the battery unit is being charged / discharged according to different charge / discharge rates, acquiring a first current-voltage profile based on the charge / discharge profile, calculating a second current-voltage profile according to a specified charge / discharge rate different from the different charge / discharge rates based on the first current-voltage profile, and calculating capacity-voltage relationship data based on the second current-voltage profile. [Effects of the Invention]

[0010] The battery diagnostic device and its operating method according to various embodiments disclosed herein can reduce the effects of overvoltage and obtain a precise charge / discharge profile of the battery.

[0011] The battery diagnostic device and its operating method according to various embodiments disclosed herein can precisely measure the relationship between the charge change amount and the voltage change amount of a battery by acquiring a precise charge / discharge profile.

[0012] The effects of the battery diagnostic device and its operating method disclosed in this document are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the disclosure of this document. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a block diagram of a battery diagnostic device according to an embodiment of the present disclosure. [Figure 2] 4 is a flowchart illustrating an operation method of a battery diagnostic device according to an embodiment of the present disclosure. [Figure 3] 4 is a flowchart showing an operation of a battery diagnostic device according to an embodiment of the present disclosure for acquiring a current-voltage profile. [Figure 4]10 is a flowchart illustrating an operation of a battery diagnostic device according to an embodiment of the present disclosure to reduce an overvoltage. DETAILED DESCRIPTION OF THE INVENTION

[0014] Embodiments of the present invention will now be described with reference to the accompanying drawings, although it should be understood that this is not intended to limit the present invention to the particular embodiments, but rather to include various modifications, equivalents, and / or alternatives to the embodiments of the present invention.

[0015] The embodiments and terms used in this document are not intended to limit the technical features described in this document to a specific embodiment, but should be understood to include various modifications, equivalents, or alternatives to the embodiment. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more of the item, unless the relevant context clearly dictates otherwise.

[0016] In this document, each phrase such as "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 or all possible combinations of the items listed with that phrase. Terms such as "first," "second," "first," "second," "A," "B," "(a)," or "(b)" may be used simply to distinguish that element from other elements and do not limit that element in other respects (e.g., importance or order) unless specifically stated to the contrary.

[0017] In this document, when a (e.g., first) component is referred to as being "coupled," "coupled," or "connected" to another (e.g., second) component, with or without the terms "functionally" or "communicatively," or when a reference is made to "coupled" or "connected," this means that the component may be coupled to the other component directly (e.g., by wire or wirelessly) or indirectly (e.g., via a third component).

[0018] Methods according to various embodiments disclosed herein may be provided in a computer program product. The computer program product may be traded between a seller and a buyer as a commodity. 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 distributed online (e.g., downloaded or uploaded) via 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 at least temporarily stored or temporarily generated on a machine-readable storage medium such as the memory of a manufacturer's server, an application store server, or an intermediary server.

[0019] According to the embodiments disclosed herein, each of the aforementioned components (e.g., modules or programs) may include one or more entities, and some of the entities may be located separately in other components. According to the embodiments disclosed herein, one or more of the aforementioned components or operations may be omitted, or one or more other components or operations may be added. Alternatively or additionally, multiple components (e.g., modules or programs) may be integrated into a single component. In this case, the integrated component may perform one or more functions of each of the multiple components in the same or similar manner as those performed by the respective components of the multiple components before the integration. According to the embodiments disclosed herein, operations performed by modules, programs, or other components may be performed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be performed in a different order, omitted, or one or more other operations may be added.

[0020] FIG. 1 is a block diagram of a battery diagnostic device 101 according to an embodiment of the present disclosure. Referring to FIG. 1, a battery diagnostic device 101 can be connected to an electronic device 103 and a user terminal 105 via wire and / or wireless.

[0021] In one embodiment, the connection between the battery diagnostic device 101 and the electronic device 103 may be a communication connection via a wired and / or wireless network. In one embodiment, the wired network may be based on a local area network (LAN) communication or a power line communication. In one embodiment, the wireless network may be based on a local area network (e.g., Bluetooth, WiFi (wireless fidelity), or IrDA (infrared data association)) or a wide area network (e.g., a cellular network, a 4G network, or a 5G network).

[0022] In another embodiment, the connection between the battery diagnostic device 101 and the electronic device 103 may be via an inter-device communication method (e.g., a bus, a general purpose input and output (GPIO), a serial peripheral interface (SPI), or a mobile industry processor interface (MIPI)).

[0023] In one embodiment, the connection between the battery diagnostic device 101 and the user terminal 105 may be a communication connection via a wired and / or wireless network.

[0024] In one embodiment, the electronic device 103 may be a mobile device (e.g., a mobile phone, a laptop computer, a smartphone, a smart pad), an electric vehicle (e.g., an electric vehicle (EV), a hybrid EV (HEV), a plug-in HEV (PHEV), or a fuel cell EV (FCEV)), an energy storage system (ESS), or a battery swapping system (BSS).

[0025] In one embodiment, the electronic device 103 may include one or more battery units 111, 113, 115. Each of the one or more battery units 111, 113, 115 may be a battery cell, a battery module, a battery pack, or a battery rack. In one embodiment, each of the one or more battery units 111, 113, 115 may be used as a power source for the electronic device 103.

[0026] In one embodiment, the user terminal 105 may be a mobile device (eg, a mobile phone, a laptop computer, a smart phone, a smart pad) or a personal computer (PC).

[0027] In one embodiment, the battery diagnostic device 101 may include a communication circuit 120, a sensor 130, a memory 140, and a processor 150. According to an embodiment, the battery diagnostic device 101 shown in Fig. 1 may further include at least one component (e.g., a display, an input device, or an output device) other than the components shown in Fig. 1 .

[0028] In one embodiment, the communication circuit 120 can establish a wired communication channel and / or a wireless communication channel between the battery diagnostic device 101 and the electronic device 103 and / or the user terminal 105, and can transmit and receive data to and from the electronic device 103 and / or the user terminal 105 via the established communication channel.

[0029] In one embodiment, the sensor 130 may obtain a value related to the status of the battery units 111, 113, 115 of the electronic device 103. In one embodiment, the value related to the status may indicate one or more values ​​for the voltage, current, resistance, state of charge (SOC), state of health (SOH), temperature, or a combination thereof, of the battery units 111, 113, 115. Hereinafter, the value related to the status may be referred to as a "status value."

[0030] In one embodiment, memory 140 may include volatile memory and / or non-volatile memory. In one embodiment, the memory 140 may store data used by at least one component (e.g., the processor 150) of the battery state estimation device 100. For example, the data may include software (or associated instructions), input data, or output data. In one embodiment, the instructions, when executed by the processor 150, may cause the battery diagnostic device 101 to perform the operation defined by the instructions.

[0031] In one embodiment, memory 140 may include one or more pieces of software (eg, a data acquisition unit 141, a profile acquisition unit 143, a profile calculation unit 145, a data calculation unit 147, and an abnormality diagnosis unit 149).

[0032] In one embodiment, processor 150 may include a central processing unit, an application processor, a graphics processing unit, a neural processing unit (NPU), an image signal processor, a sensor hub processor, or a communication processor.

[0033] In one embodiment, the processor 150 executes software (e.g., the data acquisition unit 141, the profile acquisition unit 143, the profile calculation unit 145, the data calculation unit 147, and the abnormality diagnosis unit 149), can control at least one other component (e.g., a hardware or software component) of the battery diagnostic device 101 coupled to the processor 150, and can perform various data processing or calculations.

[0034] Below, we will use battery unit 111 as an example of battery units 111, 113, and 115 to explain how battery diagnostic device 101 diagnoses abnormalities in battery unit 111 via data acquisition unit 141, profile acquisition unit 143, profile calculation unit 145, data calculation unit 147, and abnormality diagnosis unit 149.

[0035] In one embodiment, the data acquisition unit 141 may acquire charge / discharge data while the battery unit 111 is being charged / discharged. In one embodiment, the charge / discharge data may include a charge / discharge profile acquired while the battery unit 111 is being charged / discharged according to different charge / discharge rates (C-rates). Here, the charge / discharge profile may include information regarding the voltage, current, temperature, and / or SOC of the battery unit 111 while the battery unit 111 is being charged / discharged. In one embodiment, the different charge / discharge rates may include 0.1 C, 0.2 C, 0.3 C, or 1 C. However, the above-described different charge / discharge rates are merely examples and are not limited thereto.

[0036] In one embodiment, the data acquiring unit 141 can acquire the charging / discharging data using the communication circuit 120. For example, the data acquiring unit 141 can receive, using the communication circuit 120, the charging / discharging data acquired by the electronic device 103 while the battery unit 111 is being charged or discharged.

[0037] In one embodiment, the data acquiring unit 141 can acquire charge / discharge data using the sensor 130. For example, the data acquiring unit 141 can receive, from the sensor 130, detected charge / discharge data acquired by the sensor 130 during charging / discharging of the battery unit 111.

[0038] In one embodiment, the profile acquisition unit 143 can acquire a current-voltage profile based on the charge / discharge profile. In one embodiment, the current-voltage profile can include information on the relationship between the amount of change in current and the amount of change in voltage in a specified state of charge (SOC) range. In one embodiment, the specified SOC range can include the entire SOC range (i.e., 0% to 100%). In one embodiment, the specified SOC range can include a limited SOC range (e.g., 10% to 80%).

[0039] In one embodiment, the profile acquisition unit 143 can calculate a first change amount indicating a voltage change amount relative to a current change amount in a specified SOC range for each charge / discharge profile. For example, if the SOC range for calculating the first change amount is 0% to 100% and the first change amount is calculated every time the SOC increases by 0.1%, the profile acquisition unit 143 can calculate 1000 first change amounts for each charge / discharge profile.

[0040] In one embodiment, the profile acquisition unit 143 may acquire a first current-voltage profile for the charge / discharge profile based on the first change amount. Here, the first current-voltage profile may include the first change amount as information regarding the relationship between the current change amount and the voltage change amount.

[0041] In one embodiment, the first change amount may be obtained for each specified SOC interval in a specified SOC section. For example, the specified SOC interval may be 0.1%. However, the specified SOC interval is not limited thereto and may be various intervals. In one embodiment, the first change amount may be a value (dV / dI) obtained by differentiating voltage (V) with current (I) in the specified SOC section.

[0042] In one embodiment, the profile acquisition unit 143 can acquire a first current-voltage profile for the charge / discharge profile based on the second amount of change acquired by adjusting the first amount of change. Here, the first current-voltage profile can include the second amount of change as information on the relationship between the amount of change in current and the amount of change in voltage.

[0043] Specifically, the profile acquisition unit 143 can acquire the second change amount in the first SOC by adjusting the first change amount calculated at a first SOC within the SOC interval based on another first change amount calculated at a second SOC adjacent to the first SOC. The profile acquisition unit 143 can acquire the second change amount in the SOC interval by applying this process of acquiring the second change amount to the entire SOC interval. For example, if the first change amount is calculated every time the SOC increases by 0.1%, the profile acquisition unit 143 can acquire the second change amount at a specific SOC (e.g., 10%) based on the first change amount at a specific SOC (e.g., 10%) and the first change amounts at adjacent SOCs (e.g., 9.9% and 10.1%). Here, the adjustment can include averaging or weighted averaging. In one embodiment, the adjustment can also be referred to as smoothing. In one embodiment, the second change amount is acquired based on three consecutive first changes, but this is merely an example. The number of consecutive first change amounts is not limited, and various window ranges (for example, 5, 7, etc.) can be adopted.

[0044] In one embodiment, the profile calculation unit 145 may calculate a second current-voltage profile according to a specified charge / discharge rate that is different from the different charge / discharge rates based on the first current-voltage profile. Here, the specified charge / discharge rate may be lower than the different charge / discharge rates. For example, if the lowest charge / discharge rate among the different charge / discharge rates is 0.1 C, the specified charge / discharge rate may be less than 0.1 C. For example, the specified charge / discharge rate may be a charge / discharge rate close to 0 C, such as 0.01 C, 0.001 C, or a charge / discharge rate lower than 0.001 C.

[0045] In one embodiment, the profile calculation unit 145 may identify an overpotential in a specified SOC range based on the first current-voltage profile. In one embodiment, the profile calculation unit 145 may identify a voltage change amount relative to a current change amount due to the overpotential based on the first current-voltage profile. Specifically, the profile calculation unit 145 may identify a value (dV / dI) obtained by differentiating a voltage (V) increase due to the overpotential with respect to a current (I) based on the first current-voltage profile.

[0046] In one embodiment, the profile calculation unit 145 may identify a change amount indicating a voltage change amount relative to a current change amount due to different charge / discharge rates in a specified SOC range based on the first current-voltage profile. Then, the profile calculation unit 145 may identify an overvoltage due to the change amount in a specified SOC range using a specified relational expression between the charge / discharge rate and the change amount. Here, the profile calculation unit 145 may include a linear expression, a quadratic expression, a cubic expression, or an n-th order expression (n is an integer of 4 or greater) that uses the fact that the overvoltage increases as the charge / discharge rate increases.

[0047] In one embodiment, the profile calculation unit 145 may obtain the second current-voltage profile by excluding the identified overvoltage from the first current-voltage profile. For example, the profile calculation unit 145 may obtain the second current-voltage profile by excluding the identified overvoltage from at least one of the first current-voltage profiles. Here, the at least one first current-voltage profile may be a pre-selected profile from the first current-voltage profiles. For example, the at least one first current-voltage profile may be a first current-voltage profile based on a charge / discharge profile obtained at the lowest charge / discharge rate.

[0048] In one embodiment, the profile calculation unit 145 can obtain the second current-voltage profile by removing the amount of voltage change corresponding to the amount of current change due to an overvoltage from at least one first current-voltage profile. In one embodiment, the profile calculation unit 145 can obtain the second current-voltage profile by removing the value (dV / dI) obtained by differentiating the voltage (V) increase due to the overvoltage with respect to the current (I) from at least one first current-voltage profile.

[0049] In one embodiment, the data calculation unit 147 may calculate capacity-voltage relationship data based on the second current-voltage profile. Here, the capacity-voltage relationship data may indicate a relationship between a capacity change and a voltage change at a specified charge / discharge rate of the battery unit. For example, the relationship between the capacity change and the voltage change may include a value (dV / dQ) obtained by differentiating voltage (V) with charge (Q) and / or a value (dQ / dV) obtained by differentiating charge (Q) with voltage (V).

[0050] In one embodiment, the abnormality diagnosis unit 149 can diagnose whether or not there is an abnormality in the battery unit 111 based on the capacity-voltage relationship data. The battery diagnostic device 101 as described above can obtain a precise charge / discharge profile of the battery unit 111 with reduced influence of overvoltage.

[0051] 2 is a flowchart illustrating a method of operation of the battery diagnostic device 101 according to one embodiment of the present disclosure. FIG. 2 will be described with reference to the components of the battery diagnostic device 101 of FIG.

[0052] 2 , in operation 210, the battery diagnostic device 101 may acquire charge / discharge data while the battery unit 111 is being charged / discharged. In one embodiment, the battery diagnostic device 101 may acquire the charge / discharge data using the communication circuit 120 and / or the sensor 130. In one embodiment, the charge / discharge data may include a charge / discharge profile acquired while the battery unit 111 is being charged / discharged according to different charge / discharge rates. Here, the charge / discharge profile may include information regarding the voltage, current, temperature, and / or SOC of the battery unit 111 while the battery unit 111 is being charged / discharged.

[0053] In operation 220, the battery diagnostic device 101 can obtain a first current-voltage profile based on the charge / discharge profile. In one embodiment, the first current-voltage profile can include information regarding the relationship between the amount of change in current and the amount of change in voltage within a specified SOC range. In one embodiment, the specified SOC range can include the entire SOC range (i.e., 0% to 100%). In one embodiment, the specified SOC range can include a limited SOC range (e.g., 10% to 80%).

[0054] In operation 230, the battery diagnostic device 101 may calculate a second current-voltage profile according to a specified charge / discharge rate that is different from the different charge / discharge rates based on the first current-voltage profile. Here, the specified charge / discharge rate may be lower than the different charge / discharge rates. For example, if the lowest charge / discharge rate among the different charge / discharge rates is 0.1 C, the specified charge / discharge rate may be less than 0.1 C. For example, the specified charge / discharge rate may be a charge / discharge rate close to 0 C, such as 0.01 C, 0.001 C, or a charge / discharge rate lower than 0.001 C.

[0055] In operation 240, the battery diagnostic device 101 can calculate capacity-voltage relationship data based on the second current-voltage profile. Here, the capacity-voltage relationship data can indicate a relationship between a capacity change and a voltage change at a specified charge / discharge rate of the battery unit. For example, the relationship between the capacity change and the voltage change can include a value (dV / dQ) obtained by differentiating voltage (V) with charge (Q) and / or a value (dQ / dV) obtained by differentiating charge (Q) with voltage (V).

[0056] 3 is a flowchart showing an operation of the battery diagnostic device 101 according to an embodiment of the present disclosure for acquiring a current-voltage profile. The operation of FIG. 3 can be included in operation 220 of FIG. 2. FIG. 3 will be described with reference to the components of the battery diagnostic device 101 of FIG. 1.

[0057] 3, in operation 310, the battery diagnostic device 101 can calculate a first amount of change in a specified SOC range. For example, if the SOC range for calculating the first amount of change is 0% to 100% and the first amount of change is calculated every time the SOC increases by 0.1%, the battery diagnostic device 101 can calculate 1,000 first amounts of change for each charge / discharge profile. Here, the first amount of change can indicate the amount of voltage change relative to the amount of current change in a specified SOC range for each charge / discharge profile.

[0058] In operation 320, the battery diagnostic device 101 may obtain a first current-voltage profile based on the first change amount. Here, the first current-voltage profile may include the first change amount as information regarding the relationship between the current change amount and the voltage change amount. In one embodiment, the first change amount may have a value (dV / dI) obtained by differentiating voltage (V) with current (I) in a specified SOC range.

[0059] In one embodiment, the battery diagnostic device 101 can obtain a first current-voltage profile for the charge / discharge profile based on the second amount of change obtained by adjusting the first amount of change. Here, the first current-voltage profile can include the second amount of change as information on the relationship between the amount of change in current and the amount of change in voltage.

[0060] In one embodiment, the battery diagnostic device 101 can acquire the second amount of change in the first SOC by adjusting a first amount of change calculated at a first SOC in the SOC range based on another first amount of change calculated at a second SOC adjacent to the first SOC. Here, the adjustment can include averaging or weighted averaging. In one embodiment, the adjustment can also be referred to as smoothing.

[0061] 4 is a flowchart showing an operation of the battery diagnostic device 101 according to an embodiment of the present disclosure to reduce an overvoltage. The operation of FIG. 4 can be included in operation 230 of FIG. 2. FIG. 4 will be described with reference to the components of the battery diagnostic device 101 of FIG. 1.

[0062] 4, in operation 410, the battery diagnostic device 101 can identify an overvoltage in a specified SOC range. In one embodiment, the battery diagnostic device 101 can identify a voltage change amount relative to a current change amount due to the overvoltage based on a first current-voltage profile. Specifically, the battery diagnostic device 101 can identify a value (dV / dI) obtained by differentiating the voltage (V) increased by the overvoltage with respect to the current (I) based on the first current-voltage profile.

[0063] In one embodiment, the battery diagnostic device 101 may identify a variation indicating a voltage variation relative to a current variation due to different charge / discharge rates in a specified SOC range based on the first current-voltage profile. Then, the battery diagnostic device 101 may identify an overvoltage due to the variation in a specified SOC range using a specified relational expression between the charge / discharge rate and the variation. Here, the relationship may include a linear expression, a quadratic expression, a cubic expression, or an n-th order expression (n is an integer of 4 or greater) that uses the fact that the overvoltage increases as the charge / discharge rate increases.

[0064] In operation 420, the battery diagnostic device 101 may obtain a second current-voltage profile by excluding the overvoltage from the first current-voltage profile. For example, the battery diagnostic device 101 may obtain a second current-voltage profile by excluding the identified overvoltage from at least one of the first current-voltage profiles. Here, the at least one first current-voltage profile may be a pre-selected profile from the first current-voltage profiles. For example, the at least one first current-voltage profile may be a first current-voltage profile based on a charge / discharge profile obtained at the lowest charge / discharge rate.

[0065] In one embodiment, the battery diagnostic device 101 can acquire a second current-voltage profile by removing, from at least one first current-voltage profile, a voltage change amount corresponding to a current change amount due to an overvoltage. In one embodiment, the battery diagnostic device 101 can acquire a second current-voltage profile by removing, from at least one first current-voltage profile, a value (dV / dI) obtained by differentiating a voltage (V) increase due to an overvoltage with respect to a current (I).

Claims

1. a data acquisition unit that acquires charge / discharge data while the battery unit is being charged / discharged, the charge / discharge data including charge / discharge profiles acquired while the battery unit is being charged / discharged according to different charge / discharge rates; a profile acquisition unit that acquires a first current-voltage profile based on the charge / discharge profile; a profile calculation unit that calculates a second current-voltage profile at a specified charge / discharge rate different from the different charge / discharge rates based on the first current-voltage profile; a data calculation unit that calculates capacitance-voltage relationship data based on the second current-voltage profile; A battery unit diagnostic device comprising:

2. The profile acquisition unit calculating a first change amount indicating a voltage change amount relative to a current change amount in a specified SOC section for each of the charge / discharge profiles; 2. The battery unit diagnostic device according to claim 1, wherein the first current-voltage profile for the charge / discharge profile is obtained based on the first amount of change.

3. The profile acquisition unit adjusting the first change amount calculated at a first SOC in the SOC range based on another first change amount calculated at a second SOC adjacent to the first SOC, thereby obtaining a second change amount in the SOC range; 3. The battery unit diagnostic device according to claim 2, wherein the first current-voltage profile for the charge / discharge profile is obtained based on the second amount of change.

4. The profile calculation unit Identifying an overvoltage in a specified SOC range based on the first current-voltage profile; 2. The battery unit diagnostic device according to claim 1, wherein the second current-voltage profile is obtained by excluding the identified overvoltage from at least one of the first current-voltage profiles.

5. The profile calculation unit Identifying a change amount indicating a voltage change amount with respect to a current change amount due to the different charge / discharge rates in the specified SOC range based on the first current-voltage profile; The battery unit diagnostic device according to claim 4 , wherein the overvoltage caused by the amount of change in the specified SOC range is identified using a specified relational expression between the charge / discharge rate and the amount of change.

6. 6. The battery unit diagnostic device according to claim 1, wherein the capacity-voltage relationship data indicates a relationship between a capacity change amount and a voltage change amount at a specified charge / discharge rate of the battery unit.

7. The battery unit diagnostic device according to claim 1 , wherein the specified charge / discharge rate is lower than the different charge / discharge rates.

8. an operation of acquiring charge / discharge data while the battery unit is being charged / discharged, the charge / discharge data including charge / discharge profiles acquired while the battery unit is being charged / discharged according to different charge / discharge rates; obtaining a first current-voltage profile based on the charge / discharge profile; calculating a second current-voltage profile based on the first current-voltage profile, the second current-voltage profile being different from the different charge / discharge rates; calculating capacitance-voltage relationship data based on the second current-voltage profile; A method for operating a battery unit diagnostic device, comprising:

9. The act of obtaining the first current-voltage profile includes: an operation of calculating a first change amount indicating a voltage change amount relative to a current change amount in a specified SOC section for each of the charge / discharge profiles; 9. The method of operating a battery unit diagnostic device according to claim 8, further comprising: an operation of acquiring the first current-voltage profile for the charge / discharge profile based on the first amount of change.

10. The act of obtaining the first current-voltage profile includes: an operation of adjusting the first change amount calculated at a first SOC in the SOC range based on another first change amount calculated at a second SOC adjacent to the first SOC, thereby acquiring a second change amount in the SOC range; The method for operating a battery unit diagnostic device according to claim 9, further comprising: an operation of acquiring the first current-voltage profile for the charge / discharge profile based on the second amount of change.

11. The operation of calculating the second current-voltage profile includes: Identifying an overvoltage in a specified SOC range based on the first current-voltage profile; and obtaining the second current-voltage profile by excluding the identified overvoltage from at least one of the first current-voltage profiles.

12. The operation of calculating the second current-voltage profile includes: Identifying a change amount indicating a voltage change amount with respect to a current change amount due to the different charge / discharge rates in the specified SOC range based on the first current-voltage profile; and identifying the overvoltage due to the amount of change in the specified SOC range using a specified relational expression between a charge / discharge rate and the amount of change.

13. 13. The method for operating a battery unit diagnostic device according to claim 8, wherein the capacity-voltage relationship data indicates a relationship between a capacity change amount and a voltage change amount at a specified charge / discharge rate of the battery unit.

14. The method for operating a battery unit diagnostic device according to claim 8 , wherein the specified charge / discharge rate is lower than the different charge / discharge rates.

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