Battery management apparatus and charging control method thereof

Abstract

There is provided a charging control method performed by a battery management device for a battery including at least a portion of lithium metal as a negative electrode, the method comprising the steps of: charging the battery based on a first charging rate; and in response to a state of charge (SoC) of the battery reaching a threshold, charging the battery based on a second charge rate higher than the first charge rate.

Description

TECHNICAL FIELD

[0001] This application claims the benefit of priority of Korean Patent Application No. 10-2023-0165889, filed on November 24, 2023, the entire contents of which are incorporated herein by reference as part of the present specification.

[0002] The present disclosure relates to a battery management device configured to control charging of a battery including lithium metal as at least a portion of a negative electrode, and a charging control method thereof. BACKGROUND

[0003] With respect to lithium ion batteries, which are widely used in the battery field, various charging methods have been developed to increase the charging speed while having less adverse effects on the battery. One of these charging methods is a method of applying a high current rate (C-rate) at the beginning of charging when the state of charge (SoC) of the battery is low, and gradually reducing the C-rate as the charging proceeds and the SoC gradually increases. The principle of the prior art is to take advantage of the characteristic that there are many empty spaces in which lithium ions can penetrate in the negative electrode graphite at the beginning of the charging process, so even if a high C-rate is applied, fewer dendrites are formed, and thus the adverse effects on the battery are relatively small.

[0004] However, this type of charging method is difficult to apply to next-generation batteries that are expected to replace lithium ion batteries. In other words, since next-generation batteries, such as lithium-sulfur batteries, lithium metal batteries, or all-solid-state batteries, contain lithium metal in the negative electrode, many dendrites are formed even when a high C-rate is applied at an early stage of charging, and there is a problem that eventually has a significant negative impact on the battery, and thus it is difficult to apply the charging method according to the above-described prior art to next-generation batteries.

[0005] Therefore, what is needed is a new charging method that is applicable to next-generation batteries including lithium metal as at least a portion of a negative electrode and increases the charging speed while minimizing adverse effects on the battery. SUMMARY

[0006] TECHNICAL PROBLEM

[0007] The example embodiments of the present disclosure aim to provide a battery management device and a charging control method thereof. Specifically, the purpose of the present disclosure is to propose a charging method by which the charging speed of a battery including lithium metal in at least a portion of a negative electrode is increased while minimizing adverse effects on the battery by increasing the C-rate as the SoC of the battery reaches a threshold value and charging the battery.

[0008] Further, an object of the disclosure is to suggest various methods by which a threshold at which a C-rate can be increased is determined, and how much the C-rate is to be increased after the threshold is reached.

[0009] The technical tasks to be achieved by the present example embodiments are not limited to the above technical tasks, and other technical tasks can be inferred from the following example embodiments.

[0010] Technical Solution

[0011] According to an aspect, there is provided a charging control method of a battery including at least a portion of a lithium metal as a negative electrode, the method being performed by a battery management device, the method including charging the battery based on a first C-rate, and in response to a SoC of the battery reaching a threshold, charging the battery based on a second C-rate higher than the first C-rate.

[0012] According to example embodiments of the disclosure, the threshold can be determined based on a curve indicating a voltage of the negative electrode according to a SoC of the battery.

[0013] Further, according to example embodiments of the disclosure, the threshold can be determined based on a SoC corresponding to an inflection point of the curve.

[0014] Further, according to example embodiments of the disclosure, based on the curve, the threshold can be determined based on a SoC corresponding to an inflection point at which the voltage of the negative electrode increases and then decreases and then increases again as the battery is charged.

[0015] Further, according to example embodiments of the disclosure, the threshold can be determined further based on at least one of a temperature, a humidity, a pressure, and a state of health (SoH).

[0016] Further, according to example embodiments of the disclosure, the threshold can be determined by analyzing chemical reactions among lithium metal reactions occurring at the negative electrode during a charging process of the battery based on a SoC at which a ratio of the lithium metal reactions decreases to a point equal to or less than a threshold ratio.

[0017] Further, according to example embodiments of the disclosure, the first C-rate and the second C-rate can have a difference determined based on at least one of the temperature, the humidity, the pressure, and the SoH.

[0018] Further, according to example embodiments of the disclosure, the second C-rate can be selected in a range exceeding the first C-rate and equal to or less than a third C-rate.

[0019] Further, according to example embodiments of the disclosure, in a case where at least one of a discharge capacity remaining ratio and a coulombic efficiency of a charging result applied in response to the threshold being reached is identified as a candidate C-rate included in a normal range, the third C-rate can be selected to be the largest.

[0020] Further, according to example embodiments of the disclosure, when the battery includes sulfur as at least a portion of a positive electrode, the first C-rate can be 0.2C and the second C-rate can be 0.5C.

[0021] According to an aspect, there is provided a battery management system configured to control charging of a battery including lithium metal as at least a portion of a negative electrode, the battery management system including one or more sensors, a processor, and a memory configured to store one or more instructions, wherein the processor is configured to, by executing the one or more instructions, charge the battery based on a first C-rate, and in response to a SoC of the battery reaching a threshold value, charge the battery based on a second C-rate higher than the first C-rate.

[0022] Further, according to example embodiments of the disclosure, the threshold value can be determined based on a curve indicating a voltage of the negative electrode according to a SoC of the battery.

[0023] Further, according to example embodiments of the disclosure, the threshold value can be determined based on a SoC corresponding to an inflection point of the curve.

[0024] Further, according to example embodiments of the disclosure, the threshold value can be determined based on a SoC corresponding to an inflection point at which, as the battery is charged, a voltage of the negative electrode increases and then decreases and then increases again.

[0025] Further, according to example embodiments of the disclosure, the threshold value can be further determined based on at least one of a temperature, a humidity, a pressure, and an SoH.

[0026] Further, according to example embodiments of the disclosure, the threshold value can be determined by analyzing chemical reactions occurring at the negative electrode during a charging process of the battery based on a SoC of a point at which a ratio of lithium metal reactions among the chemical reactions decreases to equal to or less than a threshold ratio.

[0027] Further, according to example embodiments of the disclosure, the first C-rate and the second C-rate can have a difference determined based on at least one of a temperature, a humidity, a pressure, and an SoH.

[0028] Further, according to example embodiments of the disclosure, the second C-rate can be selected in a range exceeding the first C-rate and equal to or less than a third C-rate.

[0029] Further, according to example embodiments of the disclosure, among candidate C-rates in which at least one of a discharge capacity remaining ratio and a coulombic efficiency of a result of charging applied in response to reaching the threshold value is identified as being included in a normal range, the third C-rate can be selected to be the largest.

[0030] Also, according to example embodiments of the disclosure, when the battery contains sulfur as at least a portion of the positive electrode, the first C-rate can be 0.2C and the second C-rate can be 0.5C.

[0031] According to an aspect, there is provided a non-transitory computer-readable recording medium having a program for executing a charging control method on a computer.

[0032] Additional aspects of example embodiments will be set forth in part in the description that follows, and in part will be apparent from the description, or can be learned by practice of the disclosure.

[0033] Effects of the Invention

[0034] According to the suggested example embodiments, one or more of the following effects can be expected.

[0035] According to example embodiments of the disclosure, the adverse effects on the next-generation battery including lithium metal as at least a portion of the negative electrode can be minimized, and the charging speed can be increased.

[0036] Also, according to example embodiments of the disclosure, the optimized charging speed of the next-generation battery in any situation can be ensured by increasing the C-rate based on the optimized threshold value for each situation.

[0037] Also, according to example embodiments of the disclosure, the limit of the C-rate that can be increased after the threshold value is reached can be determined based on the discharge capacity remaining ratio and the coulomb efficiency.

[0038] Effects of the disclosure are not limited to the above-mentioned effects, and other effects not described will be apparent to those skilled in the art from the description of the claims. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 Relevance of a battery management device according to example embodiments is illustrated.

[0040] Figure 2 is a flowchart of a charging control method according to example embodiments.

[0041] Figure 3 is a graph illustrating the increase of the C-rate after the threshold value is reached according to example embodiments.

[0042] Figure 4 is a graph illustrating a curve representing the voltage of the negative electrode referred to to determine the threshold value according to example embodiments.

[0043] Figure 5 is a graph illustrating the discharge capacity remaining ratio and the coulomb efficiency when the C-rate 2-1 and the C-rate 2-2 are applied after the threshold value is reached according to example embodiments.

[0044] Figure 6 is a table including information about thresholds according to temperature, humidity, pressure, and SoH, a first C-rate, and a second C-rate according to an example embodiment.

[0045] Figure 7 A block diagram of a battery management device according to an example embodiment is shown. DETAILED DESCRIPTION

[0046] The terms used in the example embodiments are selected from general terms that are widely used at present in consideration of functions in the disclosure. However, the terms can vary depending on the intention of a person skilled in the art or a precedent, appearance of new technology, etc. Also, in some cases, there are terms arbitrarily selected by the applicant, and in these cases, the meanings will be described in detail in the corresponding description. Therefore, the terms used in the disclosure should be defined based on the meanings of the terms and the content of the disclosure, not the simple names of the terms.

[0047] Throughout the specification, when a part is described as "including or comprising" a component, it does not exclude another component, but can further include another component unless otherwise stated.

[0048] The expression "at least one of a, b, and c" described throughout the specification can include "only a," "only b," "only c," "both a and b," "both a and c," "both b and c," or "all of a, b, and c."

[0049] In the disclosure, a "terminal" can be implemented as, for example, a computer or a portable terminal that is capable of accessing a server or other terminals through a network. Here, the computer can include, for example, a notebook, a desktop computer, and / or a laptop computer equipped with a web browser. The portable terminal can be a wireless communication device that ensures portability and mobility, and includes, but is not limited to, any type of handheld wireless communication device, such as a tablet PC, a smart phone, a communication-based terminal such as International Mobile Telecommunication (IMT), Code Division Multiple Access (CDMA), W-Code Division Multiple Access (W-CDMA), Long Term Evolution (LTE), etc.

[0050] Hereinafter, example embodiments of the disclosure will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the disclosure pertains can easily implement them. However, the disclosure can be implemented in various different forms, and is not limited to the example embodiments described herein.

[0051] Hereinafter, example embodiments will be described in detail with reference to the accompanying drawings.

[0052] Figure 1 Relevance of a battery management device according to an example embodiment is shown.

[0053] Reference Figure 1 The battery management device 100 can operate in conjunction with the battery 200 and the charging device 300. At the same time, Figure 1 Only components related to the example embodiments are illustrated. Accordingly, those skilled in the art will appreciate that other general components can be included in addition to the components illustrated. Figure 1

[0054] The battery management device 100 can charge the battery 200 by controlling the current input from the charging device 300. Here, the charging device 300 can be a charger for a general battery, and can have various forms depending on the intended use and usage pattern of the battery. The battery management device 100 can control the charging of the battery in various ways, including several ways such as directly controlling the charging device 300, transmitting current and voltage information required for the charging device 300, and controlling the current input from the charging device 300 in the middle, but is not limited to the above example embodiments.

[0055] The battery 200 contemplated in the present disclosure is a battery including lithium metal as at least a part of a negative electrode, and for example, the battery 200 can be at least one of next-generation batteries such as a lithium-sulfur battery, a lithium metal battery, and an all-solid-state battery. In other words, in addition to the above example embodiments, the charging control method of the present disclosure described below can be applied to various batteries including lithium metal as at least a part of a negative electrode, and the charging control method is not limited to the above example embodiments.

[0056] Reference Figure 2 A charging control method according to an example embodiment of the present disclosure is described.

[0057] Figure 2 is a flowchart of a charging control method according to an example embodiment.

[0058] In operation S210, the battery management device 100 can charge the battery 200 based on a first C-rate. In operation S220, in response to the SoC of the battery 200 reaching a threshold value, the battery management device 100 can charge the battery based on a second C-rate higher than the first C-rate. Each operation is described in more detail below.

[0059] ​First, the battery management device 100 can charge the battery 200 based on a first C-rate. Here, the first C-rate and a second C-rate applied after the SoC threshold is reached can be a value representing the speed of battery charging, expressed as a C-rate. Specifically, the C-rate is a value calculated by dividing the charging current by the battery rated capacity, and the unit can be expressed as C = A / Ah. Accordingly, the battery management device 100 can determine the charging current to be input to the battery based on the first C-rate or the second C-rate, and can charge the battery with the corresponding charging current by working in conjunction with the charging device 300.

[0060] When operation S210 is described again, the battery management device 100 can charge the battery 200 at the first C-rate until the SoC reaches the threshold. According to an example embodiment, the first C-rate can be a value selected based on a number of values such as a discharge capacity remaining ratio or a coulomb efficiency, which can quantitatively measure the degradation of battery performance due to an increase in the number of charge / discharge cycles of the battery 200. Alternatively, according to an example embodiment, it can be a value selected in a range in which the reaction of lithium metal contained as at least a part of the negative electrode does not generate too many dendrites.

[0061] The battery management device 100 can continuously measure or monitor the SoC of the battery 200 while charging the battery 200 at the first C-rate. Then, the battery management device 100 can detect when the SoC reaches the threshold by monitoring the SoC. In response to the SoC reaching the threshold, the battery management device 100 can charge the battery 200 based on a second C-rate higher than the first C-rate. An example embodiment that increases the C-rate in this way can refer to Figure 3 .

[0062] Figure 3 is a graph showing an increase in the C-rate after the threshold is reached according to an example embodiment.

[0063] As Figure 3 shown, the battery management device 100 can charge the battery 200 based on a first C-rate 120 before the SoC reaches a threshold 110, and in response to the SoC reaching the threshold 110, and then charge the battery 200 based on a second C-rate 130 higher than the first C-rate 120. As shown, the unit of the C-rate can be C, and the unit of the SoC can be %.

[0064] The following describes the threshold as a criterion for increasing the C-rate and the second C-rate that is increased in response to the SoC reaching the threshold.

[0065] First, according to an example embodiment, a threshold can be determined based on an SoC at which a ratio of a lithium metal reaction to a chemical reaction decreases below a threshold ratio, by analyzing a chemical reaction occurring at a negative electrode during a battery charging process. Since lithium metal included as at least a part of a negative electrode can induce dendrite formation by a chemical reaction at the negative electrode, less dendrite formation can be induced even if a C-rate increases after a chemical reaction ratio of lithium metal decreases. Here, the threshold ratio can be simply set to 50%, but can be set in various ways depending on a designer's intention. In an example embodiment, the threshold ratio can be set high for fast charging of a battery, or after the threshold ratio is set low for battery stability, a threshold can be set based on an SoC at a point at which the threshold ratio is reached. In other words, the threshold ratio for determining a threshold is not limited to any value, and can have various values depending on a designer's intention.

[0066] According to an example embodiment, in the case of a lithium-sulfur battery including lithium metal as at least a part of a negative electrode, a threshold can be determined based on an SoC at which a chemical reaction at the negative electrode changes from a lithium metal reaction to a lithium-sulfur shuttle reaction. For a battery including lithium metal as at least a part of a negative electrode, such as a lithium metal battery or a full solid-state battery, a ratio of a chemical reaction of a positive electrode or other components in an electrolyte, rather than a ratio of a reaction of lithium metal at the negative electrode, can exceed a threshold ratio after a certain point of an SoC. Based on an SoC at a certain point, a threshold can be determined.

[0067] Here, a change in a ratio of a chemical reaction occurring at a negative electrode is directly identified by various chemical reaction analysis methods known in the past, or can be indirectly identified by a change in other values. In an example embodiment for indirectly identifying a change in a chemical reaction ratio, a change in a chemical reaction ratio can be estimated by a voltage of a negative electrode. Of course, a change in a negative electrode voltage can not necessarily occur due to a change in such a ratio of a chemical reaction.

[0068] According to an example embodiment, a threshold that can be used as a trigger for the above-described C-rate increase can be determined based on a curve of a negative electrode voltage indicating an SoC according to the battery 200. Here, the negative electrode voltage in the curve can have an inflection point, and thus, a threshold can be determined based on an SoC corresponding to the inflection point of the curve. Here, the inflection point can not be a mathematical inflection point, and can be a point at which a tendency of the negative electrode voltage temporarily changes due to charging.

[0069] According to an example embodiment, such an inflection point can be a point at which an absolute value of the negative electrode voltage increases, then decreases, and then increases again as the battery 200 is charged. An example embodiment for such an inflection point in a lithium-sulfur battery can refer to Figure 4 .

[0070] Figure 4 is a graph showing a curve representing a voltage of a negative electrode referred to to determine a threshold value according to an example embodiment.

[0071] Referring to Figure 4 , first to third voltage graphs (401, 402, 403) can be identified. As will be described later, the first voltage 401 can be a case where a first C-rate is maintained throughout the charging process of the lithium-sulfur battery, the second voltage graph 402 can be a case where a C-rate 2-1 higher than the first C-rate is applied in response to reaching a threshold value of SoC, and the third voltage graph 403 can be a case where a C-rate 2-2 higher than the first C-rate is applied in response to reaching the threshold value of SoC. As described above, in all three graphs, it is identified that the absolute value of the negative electrode voltage increases at a point corresponding to the threshold value 110, then decreases, and then increases again. The threshold value can be determined by the SoC value of such an inflection point, or can be selected within a certain range corresponding to the inflection point. As shown in the figure, the unit of the negative electrode voltage can be V, and the unit of the SoC can be %.

[0072] Figure 4 The illustrated negative electrode voltage curve is only an example embodiment related to a lithium-sulfur battery, and the curve can be derived differently depending on the type of the battery. Accordingly, in this way, the inflection point on the curve of the trend change of the negative electrode voltage can also be derived in various ways, and in some cases, there can be multiple inflection points. In addition, the formation of the inflection point can be due to, but not limited to, the change in the ratio of the chemical reactions described above, and example embodiments of determining the threshold value based on the inflection point formed by other factors will also be included in the scope of the present disclosure.

[0073] Then, in response to the SoC reaching the threshold value, the battery management device 100 can charge the battery 200 based on a second C-rate higher than the first C-rate. Here, the second C-rate can be selected within a range exceeding the first C-rate and being less than or equal to a third C-rate. Here, the third C-rate can be a value corresponding to the maximum C-rate, and even after reaching the threshold value, applying a C-rate that is too high can have a negative impact on the battery, and thus the third C-rate can be a value set to prevent such a case. Such a third C-rate can be selected as a C-rate having the largest size among the candidate C-rates for which at least one of the discharge capacity remaining ratio and the coulomb efficiency of the charging result applied in response to reaching the threshold value is identified to be within a normal range. In other words, a C-rate having the largest size and the maximum adverse effect on the battery identified in terms of the discharge capacity remaining ratio and the coulomb efficiency within an acceptable range can be selected as the third C-rate. According to an example embodiment, the normal range can be determined based on the discharge capacity remaining ratio and the coulomb efficiency of the control group to which the same first C-rate is applied throughout the charging process.

[0074] Accordingly, the second C-rate can be selected by the administrator through the battery management device 100 in a range exceeding the first C-rate and being lower than the third C-rate, or can be selected in the range depending on the situation by weighting the battery stability or the fast charging through a given algorithm. Referring to Figure 5 In order to check whether the discharge capacity remaining ratio and the coulomb efficiency, which can be used to select the third C-rate, are in a normal range.

[0075] Figure 5 is a graph showing the discharge capacity remaining ratio and the coulomb efficiency when C-rate 2-1 and C-rate 2-2 are applied after the threshold is reached according to an example embodiment.

[0076] Here, the discharge capacity remaining ratio can be expressed as a percentage unit of the discharge amount when the battery is connected to an open circuit, and the coulomb efficiency can indicate a ratio of the charge capacity to the discharge capacity. In Figure 5 , the first to third upper graphs 501-1 to 503-1 show the discharge capacity remaining ratio as the number of charge cycles on the horizontal axis increases, and the corresponding values can be on the vertical axis on the left. Also, the first to third lower graphs 501-2 to 503-2 show the coulomb efficiency as the number of charge cycles on the horizontal axis increases, and the corresponding values can be on the vertical axis on the right. Also, Figure 5 may be linked to Figure 4 the graph. In other words, the first upper graph 501-1 and the first lower graph 501-2 expressed as a dotted line as an index can correspond to Figure 4 the first voltage graph 401. In other words, the first upper graph 501-1 and the first lower graph 501-2 can represent the discharge capacity remaining ratio and the coulomb efficiency when the first C-rate is applied throughout the charging process, as the first voltage graph 4010, and thus the first upper graph 501-1 and the first lower graph 501-2 can be identified as the graph of the control group. Also, the second upper graph 502-1 and the second lower graph 502-2 expressed as a dotted line as an index can correspond to Figure 4 the second voltage graph 402, and can represent the discharge capacity remaining ratio and the coulomb efficiency when C-rate 2-1 is applied after the SoC reaches the threshold. Also, the third upper graph 503-1 and the third lower graph 503-2, which are expressed as a solid line as an index, correspond to Figure 4 the third voltage graph 403, and can represent the discharge capacity remaining ratio and the coulomb efficiency when C-rate 2-2 is applied after the SoC reaches the threshold. As Figure 5As identified in the above description, the second upper graph 502-1 and the second lower graph 502-2 and the third upper graph 503-1 and the third lower graph 503-2 are not greatly different from the first upper graph 501-1 and the first lower graph 501-2. In this case, both the C-rate 2-1 and the C-rate 2-2 are within the normal range, which indicates that they can be at least some of the candidate C-rates. In this way, among the candidate C-rates included in the normal range, the C-rate having the greatest size can be selected as the third C-rate in terms of the discharge capacity remaining ratio and the coulomb efficiency. Of course, example embodiments based on only one of the discharge capacity remaining ratio and the coulomb efficiency, not both, will also be within the scope of the present disclosure.

[0077] According to example embodiments, when the battery 200 includes sulfur as at least a portion of the positive electrode, in other words, for example, in the case of a lithium-sulfur battery, the first C-rate can be determined to be 0.2C and the second C-rate can be determined to be 0.5C. The first C-rate and the second C-rate can be determined according to the example embodiments described above.

[0078] In addition to the above-described change in the chemical reaction ratio or curve indicating the negative electrode voltage, the above-described threshold value can also be determined based on at least one of the temperature, humidity, pressure, and SoH of the battery 200. For example, when the temperature is high, a change such as an inflection point appearing earlier on the curve indicating the negative electrode voltage or the rate of lithium metal reaction decreasing more quickly can occur, and in this case, the threshold value can be determined to be lower, and a change in the threshold value can similarly be identified with respect to the humidity, pressure, etc. Furthermore, even if the SoH value is low, the rate of reaction of lithium metal can decrease more quickly because lithium metal has been consumed in large amounts, or an inflection point can appear earlier on the curve representing the negative electrode voltage, and thus, the threshold value can be set to be lower. All of the cases described above are example embodiments, and contrary to the example embodiments, for example, setting a higher threshold value when the temperature is high or the SoH value is low is also within the scope of the present disclosure. Furthermore, any case in which the threshold value is determined based on at least one of the temperature, humidity, pressure, and SoH is included within the scope of the present disclosure.

[0079] Furthermore, the difference between the first C-rate and the second C-rate, in other words, how much the C-rate is increased, can also be determined based on at least one of the temperature, humidity, pressure, and SoH. For example, at high temperatures, this can accelerate the formation of dendrites, or when the SoH value is low (through which a large amount of dendrites have been formed), the second C-rate can be set to be higher than the first C-rate, but the difference can be slightly smaller. The cases described above are example embodiments, and contrary to the example embodiments described above, for example, setting the second C-rate to be higher when the temperature is high or the SoH value is low is also within the scope of the present disclosure.

[0080] Further, in another example embodiment, based on the above discharge capacity remaining ratio and coulombic efficiency, the first C-rate and the second C-rate can be determined within a wide range, and the combination of the first C-rate can be determined by considering at least some of temperature, humidity, pressure, and SoH. For example, a possible example embodiment further lies in that, when the described SoH is low, dendrite formation is prevented by lowering the first C-rate applied before reaching a threshold at which dendrite formation is highly likely, and the charging speed is increased by increasing the second C-rate applied after reaching a threshold at which dendrite formation is less likely.

[0081] According to an example embodiment, together with temperature, humidity, pressure, and SoH, the battery management device 100 can refer to a table to determine the threshold, the first C-rate, and the second C-rate. In other words, the state information of the battery 200 at this time point can be identified, and the battery 200 can be charged with the application of the threshold, the first C-rate, and the second C-rate optimized for the state information based on a table including information about the threshold, the first C-rate, and the second C-rate calculated from temperature, humidity, pressure, and SoH. Figure 6 is referred to for its example embodiments.

[0082] Figure 6 is a table including information about the threshold, the first C-rate, and the second C-rate according to temperature, humidity, pressure, and SoH according to an example embodiment.

[0083] Reference Figure 6 When the humidity, the pressure, and the SoH are 30%, 1 atm, and 98%, respectively, a table including information about the threshold, the first C-rate, and the second C-rate as the temperature increases from 25℃ to 28℃ can be found. As described above, the table can be set such that the threshold and the first C-rate decrease and the second C-rate increases as the temperature increases. According to an example embodiment, the battery management device 100 can identify the state information by measuring the temperature, the humidity, and the atmospheric pressure inside the monomer and the SoH of the monomer, and then charge the battery 200 by finding the combination of the temperature, the humidity, the pressure, and the SoH having the highest similarity to the state information in the table and applying the corresponding threshold, the corresponding first C-rate value, and the corresponding second C-rate value. For convenience, Figure 6 Only the change of the threshold, the first C-rate, and the second C-rate according to the change of temperature is shown, but the actual table can include information about the threshold, the first C-rate value, and the second C-rate value that varies depending on the humidity, the pressure, and the SoH. Further, the trend of the threshold, the first C-rate, and the second C-rate according to the temperature, the humidity, the pressure, and the SoH shown in the table is only an example, and example embodiments in which the threshold, the first C-rate, and the second C-rate are set according to different trends will also be included in the scope of the present disclosure.

[0084] Figure 7 The battery management device 100 is configured to control charging of the battery 200 including at least a portion of lithium metal as a negative electrode, which is referred to describe the configuration of the battery management device 100.

[0085] Figure 7 A block diagram of an electronic device according to an example embodiment is illustrated.

[0086] According to an example embodiment, the battery management device 100 can include a memory 101, a processor 102, and one or more sensors 103. Figure 7 The illustrated battery management device 100 only illustrates components related to the example embodiment. Accordingly, those skilled in the art will understand that other general components can be included in addition to the components as described herein. In an example embodiment, the processor 102 can be included in a controller. Figure 7 The illustrated components can be included in addition to the components as described herein. In an example embodiment, the processor 102 can be included in a controller.

[0087] The one or more sensors 103 can include sensors for measuring at least some of temperature, voltage, and current used by the battery management device 100 to measure a condition of a battery cell.

[0088] The processor 102 can control the overall operation of the battery management device 100 and can process data and signals. The processor 102 can be composed of at least one hardware unit. In addition, the processor 102 can be operated by one or more software modules generated by executing program codes stored in the memory 101. Since the processor 102 can include a memory, the processor 102 can control the overall operation of the battery management device 100 and process data and signals by executing program codes stored in the memory.

[0089] The processor 102 can be configured to charge the battery based on a first C-rate by executing one or more instructions, and charge the battery based on a second C-rate higher than the first C-rate in response to the SoC of the battery reaching a threshold value. In addition, the processor 102 can be configured to perform operations to perform a charging control method for a battery including at least a portion of the above-described lithium metal as a negative electrode.

[0090] According to an example embodiment, the battery management device 100 can additionally include a transceiver for performing wired / wireless communication. The battery management device 100 can communicate with an external electronic device using the transceiver. The external electronic device can be a terminal or a server. In addition, the communication technology utilized by the transceiver can include Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Long Term Evolution (LTE), 5G, Wireless LAN (WLAN), Wireless-Fidelity (Wi-Fi), Bluetooth, Radio Frequency Identification (RFID), Infrared Data Association (IrDA), ZigBee, Near Field Communication (NFC), etc.

[0091] The system and various devices according to the above-described example embodiments can include a controller, a memory for storing and executing program data, a permanent storage device such as a disk drive, and / or user interface devices such as communication ports for communicating with external devices, touch panels, keys, and / or buttons. Methods implemented as software modules or algorithms can be stored in a computer-readable recording medium as computer-readable code or program instructions executable on the controller. Here, the computer-readable recording medium includes magnetic storage media (e.g., ROM, RAM, floppy disks, and hard disks), and optically readable media (e.g., CD-ROMs and DVDs). The computer-readable recording medium can be distributed among network-connected computer systems, so that the computer-readable code can be stored and executed in a distributed manner. The medium can be read by a computer, stored in a memory, and executed on a controller.

[0092] Example embodiments can be represented by functional block elements and various processing steps. The functional blocks can be implemented in any number of hardware and / or software configurations to perform the specified functions. For example, example embodiments can employ integrated circuit configurations, such as memories, processing, logic, and / or lookup tables, which can perform various functions by controlling one or more microprocessors or other control devices. Similar to how the elements can be implemented as software programming or software elements, example embodiments can be implemented in programming or scripting languages such as C, C++, Java, assembler, and / or the like, which include various algorithms implemented as combinations of data structures, procedures, routines, or other programming constructs. Functional aspects can be implemented in algorithms running on one or more processors. Furthermore, example embodiments can employ existing technologies for electronic environment setup, signal processing, and / or data processing. Terms such as “mechanism,” “element,” “means,” and “configuration” can be used broadly and are not limited to mechanical and physical elements. The terms can include the meaning of a series of software routines associated with a processor or the like.

[0093] The above-described example embodiments are merely examples, and other embodiments can be implemented within the scope of the claims described later.

Claims

1. A charging control method for a battery comprising at least a portion of lithium metal as a negative electrode, executed by a battery management device, the charging control method comprising: The battery is charged based on a first C rate; as well as In response to the battery's SoC reaching a threshold, the battery is charged based on a second C rate higher than the first C rate.

2. The charging control method according to claim 1, wherein, The threshold is determined based on a curve indicating the voltage of the negative electrode of the SoC of the battery.

3. The charging control method according to claim 2, wherein, The threshold is determined based on the SoC corresponding to the inflection point of the curve.

4. The charging control method according to claim 3, wherein, The threshold is determined based on the curve and the SoC corresponding to the inflection point where the voltage of the negative electrode increases, then decreases, and then increases again as the battery is charged.

5. The charging control method according to claim 2, wherein, The threshold is further determined based on at least one of temperature, humidity, pressure, and SoH.

6. The charging control method according to claim 1, wherein, The threshold is determined by analyzing the chemical reaction based on the SoC (System of Cells) of the point where the ratio of lithium metal reaction in the chemical reaction occurring at the negative electrode during the charging process of the battery decreases to equal to or less than the threshold ratio.

7. The charging control method according to claim 1, wherein, The first C-rate and the second C-rate have a difference determined based on at least one of temperature, humidity, pressure and SoH.

8. The charging control method according to claim 1, wherein, The second C rate is selected from a range that exceeds the first C rate and is equal to or less than the third C rate.

9. The charging control method according to claim 8, wherein, The third C rate is selected as the largest among candidate C rates that are included in the candidate C rate range, wherein at least one of the discharge capacity remaining ratio and coulombic efficiency is identified as the result of charging in response to reaching the threshold.

10. The charging control method according to claim 1, wherein, When the battery contains sulfur as at least a portion of the positive electrode, the first C rate is 0.2C and the second C rate is 0.5C.

11. A non-transitory computer-readable recording medium having a program for executing the charging control method of any one of claims 1 to 10 on a computer.

12. A battery management system configured to control charging of at least a portion of a battery comprising lithium metal as a negative electrode, the battery management system comprising: One or more sensors; processor; as well as The memory, configured to store one or more instructions, The processor is configured to charge the battery based on a first C rate by executing one or more instructions, and to charge the battery based on a second C rate higher than the first C rate in response to the SoC of the battery reaching a threshold.

13. The battery management system according to claim 12, wherein, The threshold is determined based on a curve indicating the voltage of the negative electrode of the SoC of the battery.

14. The battery management system according to claim 13, wherein, The threshold is determined based on the SoC corresponding to the inflection point of the curve.

15. The battery management system according to claim 14, wherein, The threshold is determined based on the curve and the SoC corresponding to the inflection point where the voltage of the negative electrode increases, then decreases, and then increases again as the battery is charged.

16. The battery management system according to claim 13, wherein, The threshold is further determined based on at least one of temperature, humidity, pressure, and SoH.

17. The battery management system according to claim 12, wherein, The threshold is determined by analyzing the chemical reaction based on the SoC (System of Cells) of the point where the ratio of lithium metal reaction in the chemical reaction occurring at the negative electrode during the charging process of the battery decreases to equal to or less than the threshold ratio.

18. The battery management system according to claim 12, wherein, The first C-rate and the second C-rate have a difference determined based on at least one of temperature, humidity, pressure and SoH.

19. The battery management system according to claim 12, wherein, The second C rate is selected from a range that exceeds the first C rate and is equal to or less than the third C rate.

20. The battery management system according to claim 19, wherein, The third C rate is selected as the largest among candidate C rates that are included in the candidate C rate range, wherein at least one of the discharge capacity remaining ratio and coulombic efficiency is identified as the result of charging in response to reaching the threshold.

21. The battery management system according to claim 12, wherein, When the battery contains sulfur as at least a portion of the positive electrode, the first C rate is 0.2C and the second C rate is 0.5C.

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