Apparatus for determining depth of charge, and operation method thereof
The charging depth determination device addresses the challenge of inaccurate charging depth estimation at low temperatures by calculating internal resistances and generating SOC-internal resistance profiles, improving charging protocol accuracy and preventing lithium deposition.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- LG ENERGY SOLUTION LTD
- Filing Date
- 2025-12-08
- Publication Date
- 2026-07-02
AI Technical Summary
Existing methods struggle to accurately determine the charging depth of lithium-ion batteries at low temperatures due to increased ohmic resistance, which affects the calculation of charge transfer resistance and State of Charge (SOC), leading to difficulties in designing charging protocols that minimize heat generation and lithium deposition.
A charging depth determination device that calculates first and second internal resistances based on voltage changes during charging periods and rest periods, generating SOC-internal resistance profiles to accurately determine the charging depth, especially at low temperatures.
The device enhances the accuracy of charging depth determination by accounting for ohmic resistance, allowing for precise control of charging protocols to prevent lithium precipitation and reduce charging time.
Smart Images
Figure KR2025020993_02072026_PF_FP_ABST
Abstract
Description
Device for determining filling depth and method of operation thereof
[0001] Cross-citation with related applications
[0002] The present invention claims the benefit of priority based on Korean Patent Application No. 10-2024-0198957 filed on December 27, 2024, and includes all contents disclosed in the document of said Korean patent application as part of this specification.
[0003] Technology field
[0004] The embodiments disclosed in this document relate to a filling depth determining device and a method of operating the same.
[0005] Recently, active research and development on secondary batteries has been underway. Here, the term "secondary battery" refers to a rechargeable battery, encompassing conventional Ni / Cd and Ni / MH batteries as well as the more recent lithium-ion batteries. Among secondary batteries, lithium-ion batteries have the advantage of significantly higher energy density compared to conventional Ni / Cd and Ni / MH batteries. Furthermore, lithium-ion batteries can be manufactured in a compact and lightweight form factor, making them suitable for use as power sources for mobile devices. Recently, their scope of application has expanded to include electric vehicles, drawing attention as a next-generation energy storage medium.
[0006] As the industrial sectors utilizing batteries expand, the demand for high-capacity batteries is also increasing. While increasing battery capacity offers the advantage of extended usage time, it also increases the charging time required. To address this charging time issue, using high current can shorten charging times, but this leads to side effects such as heat generation and lithium deposition. Consequently, active research is currently being conducted to design charging protocols that can charge high-capacity batteries in a short time while simultaneously minimizing these side effects.
[0007] To design a charging protocol, it is necessary to determine in advance the depth of charge at which lithium precipitation is expected to occur for each C-rate (current rate). As a method for determining the depth of charge, the charge transfer resistance (Rct) of the battery can be calculated, and the depth of charge can be determined based on the relationship between the charge transfer resistance and the battery's State of Charge (SOC). However, EIS inspection results for the battery at low temperatures reveal that the battery's ohmic resistance and SEI layer resistance increase in the high-frequency range. If the ohmic resistance increases, a voltage drop may occur during the idle period included in the battery charging process. Consequently, when charging a battery at low temperatures (e.g., -10°C), there is a problem in determining the depth of charge because it is difficult to calculate only the charge transfer resistance required to determine the depth of charge due to the increase in ohmic resistance.
[0008] The technical problems of the embodiments disclosed in this document are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below.
[0009] A charging depth determination device according to one embodiment disclosed in this document may include: an interface for acquiring the voltage of the battery during the process of charging the battery; and a controller for generating a charging time-voltage profile representing a change in the voltage of the battery over time, identifying a resting period in the charging time-voltage profile, calculating a first internal resistance of the battery based on a first voltage change amount corresponding to the resting period, calculating a second internal resistance of the battery based on a second voltage change amount of a designated period among the resting periods, and determining the charging depth of the battery based on the relationship between the first internal resistance and the second internal resistance and the SOC of the battery.
[0010] In one embodiment, the designated section may include a section in which a voltage drop occurs based on the ohmic resistance of the battery during the idle section.
[0011] In one embodiment, the controller can generate an SOC-internal resistance profile related to the relationship between the difference between the first internal resistance and the second internal resistance and the SOC of the battery, and determine the charge depth of the battery based on the SOC-internal resistance profile.
[0012] In one embodiment, the controller generates a first SOC-internal resistance profile related to the relationship between the first internal resistance and the SOC of the battery, generates a second SOC-internal resistance profile corrected from the first SOC-internal resistance profile based on the second internal resistance, and can determine the charge depth of the battery based on the second SOC-internal resistance profile.
[0013] In one embodiment, the battery can be charged based on a specified C-rate.
[0014] In one embodiment, the controller can generate a charging depth profile related to the relationship between the specified C-rate and the SOC based on the specified C-rate and the second SOC-internal resistance profile, and determine an upper charging depth at the specified C-rate based on the charging depth profile.
[0015] In one embodiment, the controller can calculate the first internal resistance based on the specified C-rate and the first voltage change amount, and calculate the second internal resistance based on the specified C-rate and the second voltage change amount.
[0016] A method of operation of a charge depth determination device according to an embodiment disclosed in this document may include: acquiring a voltage of the battery during the process of charging the battery; generating a charge time-voltage profile representing a change in the voltage of the battery over time; identifying a rest period in the charge time-voltage profile; calculating a first internal resistance of the battery based on a first voltage change amount corresponding to the rest period; calculating a second internal resistance of the battery based on a second voltage change amount of a designated section among the rest periods; and determining the charge depth of the battery based on the relationship between the first internal resistance and the second internal resistance and the SOC of the battery.
[0017] In one embodiment, the designated section may include a section in which a voltage drop occurs based on the ohmic resistance of the battery during the idle section.
[0018] In one embodiment, the operation of determining the charge depth of the battery may include the operation of generating an SOC-internal resistance profile related to the relationship between the difference between the first internal resistance and the second internal resistance and the SOC of the battery, and the operation of determining the charge depth of the battery based on the SOC-internal resistance profile.
[0019] In one embodiment, the operation of determining the charge depth of the battery may include the operation of generating a first SOC-internal resistance profile related to the relationship between the first internal resistance and the SOC of the battery, the operation of generating a second SOC-internal resistance profile corrected from the first SOC-internal resistance profile based on the second internal resistance, and the operation of determining the charge depth of the battery based on the second SOC-internal resistance profile.
[0020] In one embodiment, the battery can be charged based on a specified C-rate.
[0021] In one embodiment, the method of operation of the charge depth determining device may further include an operation of generating a charge depth profile related to the relationship between the specified C-rate and the SOC based on the specified C-rate and the second SOC-internal resistance profile, and the operation of determining the charge depth of the battery may include an operation of determining the upper charge depth at the specified C-rate based on the charge depth profile.
[0022] In one embodiment, the first internal resistance is calculated based on the first voltage change amount and the current based on the specified C-rate, and the second internal resistance can be calculated based on the second voltage change amount and the current based on the specified C-rate.
[0023] The charging depth determination device according to the various embodiments disclosed in this document can determine the charging depth for each C-rate more accurately than conventional methods by securing, through experimentation in advance, a section where ohmic resistance, etc., increases at low temperatures, calculating the internal resistance corresponding to the resting period and the internal resistance corresponding to the section where the ohmic resistance increases, and generating a profile related to the relationship between the difference between the two resistances and the SOC.
[0024] The effects of the battery diagnostic device and the method of operation thereof disclosed in this document are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art in accordance with the disclosure of this document.
[0025] FIG. 1 is a block diagram of a filling depth determining device according to one embodiment disclosed in this document.
[0026] FIG. 2 illustrates a charging time-voltage profile generated during the process of charging a battery at a C-rate of 1.0C according to one embodiment disclosed in this document.
[0027] FIG. 3 illustrates a charging time-voltage profile generated during the process of charging a battery at a C-rate of 0.1C according to one embodiment disclosed in this document.
[0028] Figure 4 is an enlarged view of a specific area of the charging time-voltage profile of Figure 2.
[0029] Figure 5 is an enlarged view of a specific area of the charging time-voltage profile of Figure 3.
[0030] FIG. 6 illustrates a first SOC-internal resistance profile according to one embodiment disclosed in this document.
[0031] FIG. 7 illustrates a second SOC-internal resistance profile according to an embodiment disclosed in this document.
[0032] FIG. 8 illustrates a filling depth profile according to one embodiment disclosed in this document.
[0033] Figure 9 shows a table for analyzing the filling depth profile of Figure 8.
[0034] FIG. 10 is a flowchart illustrating the operation method of a filling depth determining device according to one embodiment disclosed in this document.
[0035] FIG. 11 illustrates a computing system for executing operations of a charge depth determining device according to one embodiment disclosed in this document.
[0036] In relation to the description of the drawings, the same or similar reference numerals may be used for identical or similar components.
[0037] Hereinafter, embodiments of the present invention are described with reference to the accompanying drawings. However, this is not intended to limit the present invention to specific embodiments and should be understood to include various modifications, equivalents, and / or alternatives of the embodiments of the present invention.
[0038] The embodiments of this document and the terms used therein are not intended to limit the technical features described in this document to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of said embodiments. 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 said items unless the relevant context clearly indicates otherwise.
[0039] In this document, each of the phrases 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 of the items listed together in the corresponding phrase, or all possible combinations thereof. Terms such as “first,” “second,” “first,” “second,” “A,” “B,” “(a),” or “(b)” may be used simply to distinguish a component from another component and, unless specifically stated otherwise, do not limit the components in any other aspect (e.g., importance or order).
[0040] In this document, where it is stated that any (e.g., 1) component is "connected," "coupled," or "joined" to another (e.g., 2) component, with or without the terms "functionally" or "communicationly," or where it is stated that the component is "coupled" or "connected," it means that the component may be connected to the other component directly (e.g., by wire or wirelessly) or indirectly (e.g., through a 3) component.
[0041] Methods according to the various embodiments disclosed in this document may be provided as part of a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a device-readable storage medium (e.g., compact disc read-only memory, CD-ROM) or distributed online (e.g., download or upload) 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 created on a device-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or a relay server.
[0042] According to the embodiments disclosed in this document, each component (e.g., module or program) of the components described above may include a singular or multiple entities, and some of the multiple entities may be separated and placed in other components. According to the embodiments disclosed in this document, one or more of the components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Generally or additionally, multiple components (e.g., module or 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 components of the multiple components in the same or similar manner as those performed by the corresponding components among the multiple components prior to the integration. According to the embodiments disclosed in this document, 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] FIG. 1 is a block diagram of a filling depth determining device (10) according to one embodiment disclosed in this document.
[0044] The charging depth determining device (10) can obtain the voltage of the battery measured during the process of charging the battery. The charging depth determining device (10) can generate a charging time-voltage profile representing the change in the battery voltage over time and calculate the internal resistance of the battery based thereon. The charging depth determining device (10) can determine the charging depth at the C-rate (Current-rate) at which the battery is charged based on the calculated internal resistance. In particular, the charging depth determining device (10) can improve the accuracy of the charging depth according to the C-rate at low temperatures by calculating the final internal resistance by considering the ohmic resistance and SEI resistance that increase at low temperatures (e.g., -10 degrees Celsius). According to various embodiments, the C-rate can be understood as an indicator representing the density of the current for charging the battery. In addition, in another aspect, the C-rate can be understood as an indicator representing the charging speed of the battery.
[0045] In one embodiment, the charge depth determination device (10) may be included in a server or a charge / discharger capable of diagnosing battery cells outside of an electronic device, and operations performed by the charge depth determination device (10) may be performed in the external server or charge / discharger. In one embodiment, the charge depth determination device (10) may be included in a Battery Management System (BMS) capable of diagnosing battery cells included in an electronic device, and operations performed by the charge depth determination device (10) may be performed in the BMS. Below, operations performed in each of the components included in the charge depth determination device (10) will be described.
[0046] Referring to FIG. 1, the charge depth determining device (10) may include an interface (100) and a controller (102). According to an embodiment, the charge depth determining device (10) illustrated in FIG. 1 may further include at least one component (e.g., a display, an input device, or an output device) in addition to the components illustrated in FIG. 1.
[0047] The interface (100) can obtain the voltage of the battery during the process of charging the battery. The interface (100) can obtain the voltage of the battery during the process of charging the battery based on a specified C-rate (e.g., 1.0C). The interface (100) can obtain the voltage of the battery during the process of charging the battery based on a specified temperature (e.g., -10 degrees Celsius) and a specified C-rate (e.g., 1.0C). According to various embodiments, the interface (100) may include various interface circuits for obtaining signals, information and / or data, such as sensors and communication circuits.
[0048] The controller (102) can generate a charging time-voltage profile representing the change in voltage of the battery over time. Here, the battery can be charged based on a charging method that repeats charging and resting, and the charging time-voltage profile may include the amount of voltage change during the charging period and the amount of voltage change during the rest period.
[0049] The controller (102) can identify a rest period in the charging time-voltage profile. The controller (102) can identify a rest period in the charging time-voltage profile generated based on a charging method that repeats charging and resting.
[0050] The controller (102) can calculate a first internal resistance and a second internal resistance based on a charging time-voltage profile, and can determine the charging depth based on an SOC-internal resistance profile related to the relationship between the first internal resistance and the second internal resistance and the SOC of the battery.
[0051] The controller (102) can calculate a first internal resistance of the battery based on a first voltage change amount corresponding to a rest period. Here, the first internal resistance may include charge transfer resistance (Rct), ohmic resistance (Ro), and / or solid electrolyte interphase resistance (RSEI). The first internal resistance can be calculated based on a first voltage change amount and a current value according to the C-rate at which the battery is charged.
[0052] The controller (102) can generate a first SOC-internal resistance profile related to the relationship between the first internal resistance and the battery's SOC (State Of Charge).
[0053] The controller (102) can identify a designated section during the idle period. Here, the designated section may refer to a section in which a voltage drop occurs based on the ohmic resistance of the battery, which is at least a portion of the section included in the idle period. Here, the voltage drop section may refer to a section in which the voltage of the battery drops rapidly during the idle period immediately after the charging section for the battery.
[0054] The controller (102) can calculate a second internal resistance of the battery based on a second voltage change amount in a designated interval. Here, the second internal resistance may include an ohmic resistance and / or an SEI resistance. The second internal resistance can be calculated based on a second voltage change amount and a current value according to the C-rate at which the battery is charged.
[0055] Based on the above, the charging depth determining device (10) can calculate the first internal resistance and the second internal resistance due to the ohmic resistance, respectively, and based on the content to be described later in FIGS. 2 to 11, it can calculate only the internal resistance corresponding to the charge transfer resistance that has a significant influence on the charging depth determination, thereby improving the accuracy in determining the charging depth.
[0056] The controller (102) can generate a second SOC-internal resistance profile based on the second internal resistance. The controller (102) can generate a second SOC-internal resistance profile based on the relationship between the difference between the first internal resistance and the second internal resistance and the SOC.
[0057] In one embodiment, the controller (102) can generate a second SOC-internal resistance profile by correcting the first SOC-internal resistance profile based on the second internal resistance. For example, the controller (102) can generate a second SOC-internal resistance profile by performing an operation or correction of subtracting each of the values corresponding to the second internal resistance from each of the values corresponding to the first internal resistance included in the first SOC-internal resistance profile.
[0058] The controller (102) can determine the charge depth of the battery based on the second SOC-internal resistance profile. The controller (102) can determine the upper charge depth for each C-rate of charging the battery based on the second SOC-internal resistance profile. Here, the upper charge depth may refer to the State of Charge (SOC) of the battery at which lithium precipitation begins to occur during the process of charging the battery at each C-rate.
[0059] The controller (102) can generate a charging protocol for charging the battery based on the charging upper limit charging depth for each C-rate.
[0060] FIG. 2 illustrates a charging time-voltage profile generated during the process of charging a battery at a C-rate of 1.0C according to an embodiment disclosed in this document. FIG. 3 illustrates a charging time-voltage profile generated during the process of charging a battery at a C-rate of 0.1C according to an embodiment disclosed in this document. FIG. 4 is an enlarged view of a specific area of the charging time-voltage profile of FIG. 2. FIG. 5 is an enlarged view of a specific area of the charging time-voltage profile of FIG. 3. Hereinafter, with reference to FIG. 2 to FIG. 5 together, a method for the charging depth determining device (10) to calculate the first internal resistance and the second internal resistance will be described.
[0061] Referring to FIGS. 2 and FIGS. 3, the charging time-voltage profile (20) of FIG. 2 and the charging time-voltage profile (30) of FIG. 3 illustrate the change in voltage of a battery over time during a charging process in which charging and resting periods are repeated. The charging time-voltage profile (20) of FIG. 2 is a profile generated during the process of charging the battery at a C-rate of 1.0C and a temperature of -10°C, and the charging time-voltage profile (20) of FIG. 3 may be a profile generated during the process of charging the battery at a C-rate of 0.1C and a temperature of -10°C. The charging depth determining device (10) can identify the resting period included in each of the charging time-voltage profiles (20, 30).
[0062] FIG. 4 illustrates a first graph (40) that is enlarged to the area corresponding to the idle period of the charging time-voltage profile (20) of FIG. 2. FIG. 5 illustrates a second graph (50) that is enlarged to the area corresponding to the idle period of the charging time-voltage profile (30) of FIG. 3.
[0063] When referring to the first graph (40) and the second graph (50) together, the x-axis may represent charging time and the y-axis may represent voltage. The first point (400) to the fourth point (406) of the first graph (40) may correspond to the first point (500) to the fourth point (506) of the second graph (50), respectively. The first point (400) of the first graph (40) and the first point (500) of the second graph (50) may each be the point where the voltage drop section begins. The section between the first point (400) to the third point (404) of the first graph (40) and the section between the first point (500) to the third point (504) of the second graph (50) may be the section where a voltage drop occurs due to the ohmic resistance.
[0064] The charging depth determining device (10) can calculate a first internal resistance. The charging depth determining device (10) can calculate a first internal resistance based on a first voltage change amount between a first point (400) and a fifth point (408) of a first graph (40). The charging depth determining device (10) can calculate a first internal resistance based on a first voltage change amount between a first point (500) and a fifth point (508) of a second graph (50).
[0065] The charging depth determining device (10) can identify a designated section during the idle period to calculate the second internal resistance. Here, the designated section may refer to a section where a voltage drop commonly occurs due to ohmic resistance during low-rate charging or high-rate charging of the battery. Ohmic resistance is an internal resistance of the battery that rises in the high-frequency region at low temperatures (e.g., -10 degrees Celsius) and may affect the voltage reduction during the idle period of the battery. For example, by referring to the first graph (40) and the second graph (50), the voltage reduction time at the first point (36,037 seconds, 400) to the third point (36,037.3 seconds, 404) of the first graph (40) and the voltage reduction time at the first point (43,569.05 seconds, 500) to the third point (43,569.34 seconds, 500) of the second graph (50) may be the same at 0.3 seconds. In this case, the charging depth determining device (10) can identify the first point (400, 500) to the second point (402, 502) corresponding to the voltage reduction time that occurs commonly in the resting periods of the first graph (40) and the second graph (50) as designated sections.
[0066] The charging depth determining device (10) can identify a designated section based on a first graph (40) generated based on high-rate charging with a C-rate of 1.0C and a second graph (50) generated based on low-rate charging with a C-rate of 0.1C. The charging depth determining device (10) can identify the time of a voltage drop section that occurs commonly in the first graph (40) and the second graph (50). Here, the time of the voltage drop section may correspond to the time between the first point (400) and the third point (404) of the first graph (40) and the time between the first point (500) and the third point (504) of the second graph (50), and the time of the voltage drop section may be 0.3 seconds. The time during which the voltage drop due to ohmic resistance occurs can be determined through preliminary experiments by comparing the charging time-voltage profiles obtained for each C-rate to obtain a common time interval (e.g., 0.3s) during which the voltage drop due to ohmic resistance occurs.
[0067] The charging depth determining device (10) can calculate a second internal resistance corresponding to a time (e.g., 0.3 seconds) corresponding to a designated interval. The charging depth determining device (10) can calculate the second internal resistance based on a second voltage change amount in the designated interval and a current value based on the C-rate at which the battery is charged. Here, the second internal resistance may refer to an ohmic resistance, and the designated interval may be an interval where a voltage drop occurs due to the ohmic resistance.
[0068] FIG. 6 illustrates a first SOC-internal resistance profile according to an embodiment disclosed in this document. FIG. 7 illustrates a second SOC-internal resistance profile according to an embodiment disclosed in this document. Hereinafter, with reference to FIG. 6 and FIG. 7, a method in which a charge depth determining device (10) generates a first SOC-internal resistance profile and a second SOC-internal resistance profile based on a first internal resistance and a second internal resistance will be described.
[0069] Referring to FIG. 6, the charge depth determining device (10) can generate a first SOC-internal resistance profile (60) related to the relationship between the first internal resistance and the SOC of the battery. The charge depth determining device (10) can calculate the first internal resistance based on a charging time-voltage profile for a plurality of C-rates (e.g., 0.1C, 0.2C, ..., 1.0C), and can generate a first SOC-internal resistance profile (60) related to the relationship between the first internal resistance for a plurality of C-rates and the SOC of the battery.
[0070] Referring to FIG. 7, the charge depth determining device (10) can generate a second SOC-internal resistance profile (70) based on the second internal resistance. The charge depth determining device (10) can calculate the second internal resistance based on a charging time-voltage profile for a plurality of C-rates (e.g., 0.1C, 0.2C, ..., 1.0C) and can generate a second SOC-internal resistance profile (70) based on the second internal resistance.
[0071] In one embodiment, the charge depth determining device (10) can calculate the difference between the first internal resistance and the second internal resistance, and can generate a second SOC-internal resistance profile (80) related to the relationship between the difference and the SOC.
[0072] In one embodiment, the charge depth determining device (10) can generate a second SOC-internal resistance profile by correcting the first SOC-internal resistance profile (60) based on the second internal resistance. For example, the second SOC-internal resistance profile (80) can be generated by performing a correction that subtracts the second internal resistance corresponding to the SOC corresponding to the first internal resistance from the first internal resistance included in the first SOC-internal resistance profile.
[0073] FIG. 8 illustrates a filling depth profile according to an embodiment disclosed in this document. FIG. 9 illustrates a table for analyzing the filling depth profile of FIG. 8.
[0074] Referring to FIG. 8, the charging depth determining device (10) can generate a charging depth profile (80) including a charging upper limit charging depth for each C-rate based on a second SOC-internal resistance profile. Here, the charging upper limit charging depth may refer to the SOC at which lithium precipitation begins for each C-rate.
[0075] Referring to FIG. 9, the table (90) may include values related to the upper charging depth per C-rate based on a first SOC-internal resistance profile related to the relationship between the first internal resistance and SOC calculated for each of the battery cells (#1, #2) during the process of charging the battery cells (#1, #2) at a specified temperature (e.g., -10 degrees Celsius). Specifically, the first battery cell (#1) may be charged with a C-rate value between 1.0C and 0.1C during the process of charging at -10 degrees Celsius, and the table (90) may include results relating the SOC at which lithium precipitation begins to occur for each C-rate. For example, referring to the table (90), when the first battery cell (#1) is charged at 1.0C, the upper charging depth may be 58%.
[0076] Additionally, the table (90) may include values related to the upper limit charging depth by C-rate based on a second SOC-internal resistance profile corrected for the first SOC-internal resistance of the first battery cell (#1). Referring to the table (90), the values included in the column for cell #1 (before correction) may correspond to the upper limit charging depth by C-rate determined based on the first SOC-internal resistance profile of the first battery cell (#1). The values included in the column for cell #2 (before correction) may correspond to the upper limit charging depth by C-rate determined based on the first SOC-internal resistance profile of the second battery cell (#2). The values included in the column for Average may correspond to the average value of the upper limit charging depth by C-rate of the battery cells (#1, #2). The values included in the column of cell #1 (after correction) may correspond to the charging upper limit charging depth by C-rate calculated based on the second SOC-internal resistance profile, which corrects the first SOC-internal resistance profile based on the second internal resistance of the first battery cell (#1).
[0077] Referring to FIGS. 8 and FIGS. 9 together, the charge depth profile (80) may include a first charge depth profile (800) generated based on a first SOC-internal resistance and a second charge depth profile (810) generated based on a second SOC-internal resistance. Referring to the first charge depth profile (80) and the table (90), it can be seen that the first charge depth profile (80) is unclear regarding the upper charge depth at a specific C-rate. This may mean that the upper charge depth is not accurately detected due to an increase in ohmic resistance at low temperatures. On the other hand, it can be seen that the second charge depth profile (810) clearly detects the upper charge depth for each of the multiple C-rates.
[0078] Based on the above description, the charging depth determining device (10) can solve the problem of reduced accuracy of charging depth due to an increase in the ohmic resistance of the battery at low temperatures by determining the upper charging depth for each C-rate using the second SOC-internal resistance profile.
[0079] FIG. 10 is a flowchart illustrating the operation method of a filling depth determining device according to one embodiment disclosed in this document.
[0080] Referring to FIG. 10, in operation 1000, the charging depth determining device (10) can obtain the voltage of the battery. The charging depth determining device (10) can obtain the voltage of the battery during the process of charging the battery. The charging depth determining device (10) can obtain the voltage of the battery during the process of charging the battery based on a specified C-rate (e.g., 1.0C). The charging depth determining device (10) can obtain the voltage of the battery during the process of charging the battery based on a specified temperature (e.g., -10 degrees Celsius) and a specified C-rate (e.g., 1.0C).
[0081] In operation 1010, the charge depth determining device (10) can generate a charge time-voltage profile.
[0082] In operation 1020, the charging depth determining device (10) can identify a rest period in the charging time-voltage profile. The charging depth determining device (10) can identify a rest period in the charging time-voltage profile. The charging depth determining device (10) can identify a rest period in the charging time-voltage profile generated based on a charging method that repeats charging and resting.
[0083] In operation 1030, the charging depth determining device (10) can calculate a first internal resistance based on a first voltage change amount corresponding to a rest period.
[0084] In operation 1040, the charge depth determining device (10) can calculate a second internal resistance based on a second voltage change amount in a designated section during the idle period. The charge depth determining device (10) can identify a designated section during the idle period. Here, the designated section may refer to a section included in the idle period where a voltage drop occurs based on the ohmic resistance of the battery.
[0085] The charging depth determining device (10) can calculate the second internal resistance of the battery based on the second voltage change amount of the designated section.
[0086] In operation 1050, the charge depth determining device (10) can determine the charge depth of the battery based on the relationship between the first internal resistance and the second internal resistance and the SOC of the battery.
[0087] The charge depth determining device (10) can generate a first SOC-internal resistance profile related to the relationship between the first internal resistance and the SOC (State Of Charge) of the battery.
[0088] The charge depth determining device (10) can generate a second SOC-internal resistance profile based on the second internal resistance. The charge depth determining device (10) can generate a second SOC-internal resistance profile based on the relationship between the difference between the first internal resistance and the second internal resistance and the SOC.
[0089] In one embodiment, the charge depth determining device (10) can generate a second SOC-internal resistance profile by correcting the first SOC-internal resistance profile based on the second internal resistance. For example, the charge depth determining device (10) can generate a second SOC-internal resistance profile by performing a correction that subtracts each of the values corresponding to the second internal resistance from each of the values corresponding to the first internal resistance included in the first SOC-internal resistance profile.
[0090] According to an embodiment, the charging depth determining device (10) can determine the charging depth of the battery based on the second SOC-internal resistance profile. The charging depth determining device (10) can determine the upper charging depth for each C-rate of the battery based on the second SOC-internal resistance profile.
[0091] According to an embodiment, the charging depth determining device (10) can generate a charging protocol for charging a battery based on the charging upper limit charging depth for each C-rate.
[0092] FIG. 11 illustrates a computing system for executing operations of a charge depth determining device according to one embodiment disclosed in this document.
[0093] Referring to FIG. 11, a computing system (1100) according to one embodiment disclosed in this document may include an MCU (1110), a memory (1120), an input / output I / F (1130), and a communication I / F (1140).
[0094] The MCU (1110) may be a processor that executes various programs stored in memory (1120), processes various data from these programs, and performs the functions of the charge depth determining device (10) shown in the aforementioned FIGS. 1 to 10.
[0095] The memory (1120) can store various programs regarding the operation of the charge depth determining device (10). In addition, the memory (1120) can store operation data of the charge depth determining device (10).
[0096] These memories (1120) may be provided in multiple quantities as needed. The memories (1120) may be volatile memories or non-volatile memories. As volatile memories, the memory (1120) may use RAM, DRAM, SRAM, etc. As non-volatile memories, the memory (1120) may use ROM, PROM, EAROM, EPROM, EEPROM, flash memory, etc. The memories (1120) listed above are merely examples and are not limited to these examples.
[0097] The input / output I / F (1130) can provide an interface that enables data transmission and reception between an input device (not shown), such as a keyboard, mouse, or touch panel, an output device (not shown), and an MCU (1110).
[0098] The communication I / F (1140) is configured to transmit and receive various data with a server and may be various devices capable of supporting wired or wireless communication. For example, through the communication I / F (1140), a program for determining the charge depth of a battery or various data (e.g., time corresponding to a designated interval) can be transmitted and received from a separately provided external server.
[0099] Terms such as "include," "compose," or "have" as used above, unless specifically stated otherwise, mean that the relevant component may be inherent; therefore, they should be interpreted as allowing for the inclusion of additional components rather than excluding them. All terms, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the embodiments disclosed in this document pertain, unless otherwise defined. Commonly used terms, such as those defined in advance, should be interpreted in accordance with their meaning in the context of the relevant technology and, unless explicitly defined in this document, should not be interpreted in an ideal or overly formal sense.
[0100] The foregoing description is merely an illustrative explanation of the technical concept disclosed in this document, and a person skilled in the art to which the embodiments disclosed in this document pertain can make various modifications and variations within the scope of the essential characteristics of the embodiments disclosed in this document. Accordingly, the embodiments disclosed in this document are intended to explain, not limit, the technical concept of the embodiments disclosed in this document, and the scope of the technical concept disclosed in this document is not limited by these embodiments. The scope of protection of the technical concept disclosed in this document shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of this document.
Claims
1. An interface for obtaining the voltage of the battery during the process of charging the battery; and Generate a charging time-voltage profile representing the change in voltage of the above battery over time, and Identify the idle period in the above charging time-voltage profile, and Calculate the first internal resistance of the battery based on the first voltage change amount corresponding to the above idle period, and Calculate the second internal resistance of the battery based on the second voltage change amount of a designated section among the above idle sections, and A controller comprising a charge depth of the battery based on the relationship between the first internal resistance and the second internal resistance and the SOC of the battery. Fill depth determining device.
2. In Claim 1, The above-mentioned specified section includes a section in which a voltage drop occurs based on the ohmic resistance of the battery during the above-mentioned idle section. Fill depth determining device.
3. In Claim 1, The above controller is, Generate an SOC-internal resistance profile related to the relationship between the difference between the first internal resistance and the second internal resistance and the SOC of the battery, and Determining the charge depth of the battery based on the above SOC-internal resistance profile, Fill depth determining device.
4. In Claim 1, The above controller is, Generate a first SOC-internal resistance profile related to the correlation between the first internal resistance and the SOC of the battery, and A second SOC-internal resistance profile is generated by correcting the first SOC-internal resistance profile based on the second internal resistance, and Determining the charge depth of the battery based on the above second SOC-internal resistance profile, Fill depth determining device.
5. In Claim 4, The above battery is charged based on a specified C-rate, Fill depth determining device.
6. In Claim 5, The above controller is, Based on the specified C-rate and the second SOC-internal resistance profile, a charge depth profile related to the correlation between the specified C-rate and the SOC is generated, and Determining the upper limit filling depth at the specified C-rate based on the above filling depth profile, Fill depth determining device.
7. In Claim 5, The above controller is, Calculate the first internal resistance based on the specified C-rate and the first voltage change amount, and Calculating the second internal resistance based on the specified C-rate and the second voltage change amount, Fill depth determining device.
8. An operation to obtain the voltage of the battery during the process of charging the battery; The operation of generating a charging time-voltage profile indicating the change in voltage of the battery over time; An operation to identify a rest period in the above charging time-voltage profile; An operation to calculate the first internal resistance of the battery based on the first voltage change amount corresponding to the above idle period; The operation of calculating the second internal resistance of the battery based on the second voltage change amount of a designated section among the above idle sections; and The method includes an operation of determining the charge depth of the battery based on the relationship between the first internal resistance and the second internal resistance and the SOC of the battery. Method of operation of a filling depth determining device.
9. In Claim 8, The above-mentioned specified section includes a section in which a voltage drop occurs based on the ohmic resistance of the battery during the above-mentioned idle section. Method of operation of a filling depth determining device.
10. In claim 8, The operation of determining the charge depth of the above battery is, The operation of generating an SOC-internal resistance profile related to the relationship between the difference between the first internal resistance and the second internal resistance and the SOC of the battery, and A method including an operation to determine the charge depth of the battery based on the above SOC-internal resistance profile, Method of operation of a filling depth determining device.
11. In Claim 8, The operation of determining the charge depth of the above battery is, The operation of generating a first SOC-internal resistance profile related to the correlation between the first internal resistance and the SOC of the battery, The operation of generating a second SOC-internal resistance profile that corrects the first SOC-internal resistance profile based on the second internal resistance, and A method comprising determining the charge depth of the battery based on the second SOC-internal resistance profile. Method of operation of a filling depth determining device.
12. In Claim 11, The above battery is charged based on a specified C-rate, Method of operation of a filling depth determining device.
13. In Claim 12, The method further includes the operation of generating a charge depth profile related to the correlation between the specified C-rate and the SOC based on the specified C-rate and the second SOC-internal resistance profile, and The operation of determining the charge depth of the above battery is, The operation of determining the upper limit filling depth at the specified C-rate based on the above filling depth profile, Method of operation of a filling depth determining device.
14. In Claim 12, The first internal resistance is calculated based on the first voltage change amount and the current based on the specified C-rate, and The second internal resistance is calculated based on the second voltage change amount and the current based on the specified C-rate, Method of operation of a filling depth determining device.