Battery management device and charging control method thereof

Abstract

This disclosure provides a battery management device and a charging control method therefor. The provided charging control method for a battery, in which lithium metal is at least a portion of the negative electrode, includes the steps of: charging the battery based on a first charge rate performed by the battery management device; and charging the battery based on a second charge rate higher than the first charge rate in response to the battery's State-of-Charge (SoC) reaching a threshold.

Description

Technical Field

[0001] This application claims the benefit of priority based on Republic of Korea Patent Application No. 10-2023-0165889 filed on November 24, 2023, and all the contents disclosed in the documents of the Republic of Korea Patent Application are incorporated herein by reference.

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

Background Art

[0003] Regarding lithium-ion batteries widely used in the battery field, various charging methods have been developed to increase the charging speed while minimizing adverse effects on the battery. One such charging method is to apply a high charging rate (C-rate) at the beginning of charging, i.e., when the state of charge (SoC) of the battery is low, and then gradually decrease the charging rate as the SoC increases during charging. The principle of such a conventional technique utilizes the characteristic that at the beginning of the charging process, there are many empty spots in the graphite of the negative electrode for lithium ions to penetrate, and even when a high charging rate is applied, dendrites are formed less, and the adverse effects on the battery are relatively small.

[0004] However, such a charging method is difficult to apply to next-generation batteries that are expected to replace lithium-ion batteries. That is, next-generation batteries, such as lithium-sulfur batteries, lithium-metal batteries, or all-solid-state batteries, contain lithium metal in the negative electrode. Therefore, when a high charging rate is applied even at the beginning of charging, many dendrites are formed, and ultimately, there is a problem that the adverse effects on the battery are significant. Thus, it is difficult to apply the charging method according to the above-described conventional technique to next-generation batteries.

[0005] Therefore, a new charging method is needed that can be applied to next-generation batteries containing lithium metal as at least a portion of the negative electrode, while minimizing adverse effects on the battery and increasing the charging speed. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The disclosed embodiments provide a battery management device and a charging control method thereof. Specifically, one objective of this disclosure is to provide a charging method that can increase the charging rate of a battery containing lithium metal in at least a portion of the negative electrode while minimizing adverse effects on the battery, by increasing the charge rate when the battery's charge state reaches a threshold.

[0007] Furthermore, this disclosure aims to propose a threshold that can increase the charge level, and various methods for determining how much to increase the charge level after reaching the threshold.

[0008] The technical problems that this embodiment aims to solve are not limited to those described above, and other technical problems can be inferred from the following embodiments. [Means for solving the problem]

[0009] One aspect of this disclosure is a method for controlling the charging of a battery, which includes lithium metal as at least a portion of the negative electrode, performed by a battery management device, and which includes the steps of: charging the battery based on a first charge rate; and charging the battery based on a second charge rate higher than the first charge rate in response to the battery's charge state (State-of-Charge, SoC) reaching a threshold.

[0010] In one embodiment of the present disclosure, the threshold may include a charging control method in which the threshold is determined based on a profile indicating the voltage of the negative electrode corresponding to the SoC of the battery.

[0011] Furthermore, in one embodiment of the present disclosure, the threshold may include a charge control method in which the threshold is determined based on the SoC corresponding to the inflection point of the profile.

[0012] Furthermore, in one embodiment of the present disclosure, the threshold may include a charging control method in which the threshold is determined based on the SoC corresponding to the inflection point where the voltage of the negative electrode increases, then decreases, and then increases again in response to the charging of the battery, based on the profile.

[0013] Furthermore, in one embodiment of the present disclosure, the threshold may include a charging control method determined based on at least one of temperature, humidity, atmospheric pressure, and state-of-health (SoH).

[0014] Furthermore, in one embodiment of the present disclosure, the threshold may include a charging control method that analyzes the chemical reactions occurring at the negative electrode during the charging process of the battery and determines the threshold based on the SoC at which the proportion of the lithium metal reaction in the chemical reactions decreases to or below a threshold ratio.

[0015] Furthermore, in one embodiment of the present disclosure, the difference between the first charge level and the second charge level may include a charge control method that determines the difference based on at least one of temperature, humidity, atmospheric pressure, and SoH.

[0016] Furthermore, in one embodiment of the present disclosure, the second charge level may include a charging control method selected within a range of exceeding the first charge level and being equal to or less than the third charge level.

[0017] Furthermore, in one embodiment of the present disclosure, the third charge level may include a charge control method in which the largest of a list of candidate charge levels is selected, in which at least a portion of the remaining discharge capacity and Coulomb efficiency for the charge result applied in response to reaching the threshold is confirmed to fall within the normal range.

[0018] Furthermore, in one embodiment of the present disclosure, if the battery contains sulfur as at least a portion of the positive electrode, a charge control method may be included in which the first charge level is 0.2C and the second charge level is 0.5C.

[0019] Another aspect of the present disclosure is a battery management system for controlling the charging of a battery having lithium metal as at least a portion of the negative electrode, comprising one or more sensors, a processor, and a memory for storing one or more instructions, wherein the processor is configured to charge the battery based on a first charge rate by issuing the one or more instructions, and to charge the battery based on a second charge rate higher than the first charge rate in response to the battery's State-of-Charge (SoC) reaching a threshold.

[0020] In one embodiment of the present disclosure, the threshold may include a battery management system that determines the threshold based on a profile indicating the voltage of the negative electrode corresponding to the SoC of the battery.

[0021] Furthermore, in one embodiment of the present disclosure, the threshold may include a battery management system determined based on the SoC corresponding to the inflection point of the profile.

[0022] Furthermore, in one embodiment of the present disclosure, the threshold may include a battery management system that determines the threshold based on the SoC corresponding to the inflection point where the voltage of the negative electrode increases, then decreases, and then increases again in response to the charging of the battery, based on the profile.

[0023] Furthermore, in one embodiment of the present disclosure, the threshold may include a battery management system that is determined based on at least one of temperature, humidity, atmospheric pressure, and state-of-health (SoH).

[0024] Also, in one embodiment of the present disclosure, the threshold value can include a battery management system determined based on the state of charge (SoC) at a point where the ratio of the lithium metal reaction in the chemical reactions occurring at the negative electrode during the charging process of the battery decreases to a threshold ratio or less by analyzing the chemical reactions occurring at the negative electrode.

[0025] Also, in one embodiment of the present disclosure, the difference between the first charging rate and the second charging rate can include a battery management system determined based on at least one of temperature, humidity, atmospheric pressure, and state of health (SoH).

[0026] Also, in one embodiment of the present disclosure, the second charging rate can include a battery management system selected within a range exceeding the first charging rate and not exceeding the third charging rate.

[0027] Also, in one embodiment of the present disclosure, the third charging rate can include a battery management system selected as the largest among the candidate charging rates confirmed that at least a part of the residual rate of the discharge capacity and the Coulomb efficiency with respect to the charging result applied in response to reaching the threshold value is included within the normal range.

[0028] Also, in one embodiment of the present disclosure, when the battery includes sulfur as at least a part of the positive electrode, the first charging rate can be 0.2C and the second charging rate can be 0.5C, and a battery management system can be included.

[0029] Still another aspect of the present disclosure can provide a computer-readable non-transitory recording medium recording a program for causing a computer to execute the charging control method described above.

[0030] In addition, specific matters of the embodiments are included in the detailed description and the drawings.

Advantages of the Invention

[0031] According to the proposed embodiment, one or more of the following effects can be expected:

[0032] According to embodiments of this specification, it is possible to increase the charging speed while minimizing adverse effects on next-generation batteries that include lithium metal as at least a portion of the negative electrode.

[0033] Furthermore, according to the embodiments of this specification, by increasing the charge rate based on thresholds optimized for various situations, it is possible to ensure an optimized charging speed for next-generation batteries in any situation.

[0034] Furthermore, according to embodiments of this specification, it is also possible to determine a limit value for the charge level that can be increased after reaching a threshold, based on the remaining discharge capacity and the Coulomb efficiency.

[0035] The effects of this disclosure are not limited to those described above, and any other effects not mentioned can be clearly understood by those skilled in the art from the claims. [Brief explanation of the drawing]

[0036] [Figure 1] This shows the interlocking relationships of a battery management device according to one embodiment. [Figure 2] This is a flowchart of a charging control method according to one embodiment. [Figure 3] This graph shows the increase in the charge rate after reaching a threshold according to one embodiment. [Figure 4] This is a graph showing a profile of the negative electrode voltage, which is referenced to determine the threshold value according to one embodiment. [Figure 5] This graph shows the remaining discharge capacity and Coulomb efficiency when the 2-1 charge rate and 2-2 charge rate are applied after reaching the threshold according to one embodiment. [Figure 6] This is an illustrative diagram of a table containing information regarding temperature, humidity, atmospheric pressure, and thresholds, first charge level, and second charge level according to one embodiment. [Figure 7] A block diagram of a battery management device according to one embodiment is shown. [Modes for carrying out the invention]

[0037] The terminology used in the embodiments has been selected, to the greatest extent possible, to be common and widely used terms, taking into account the function described herein, although this may change depending on the intent of the articulators, case law, the emergence of new technologies, etc. In certain cases, the applicant has also arbitrarily selected some terms, in which case their meanings will be described in detail in the relevant explanatory sections. Therefore, the terms used in this disclosure must be defined not merely as names of terms, but based on the meaning of the terms and the overall content of this disclosure.

[0038] When a part of the specification is described as "including" a certain component, unless otherwise stated, this does not mean that other components are excluded, but rather that other components may be included.

[0039] The expression “at least one of a, b, and c” as described throughout the specification may encompass “a alone,” “b alone,” “c alone,” “a and b,” “a and c,” “b and c,” or “all of a, b, and c.”

[0040] The term "terminal" as used below can be embodied in computers or portable terminals that can connect to servers or other terminals via a network. Here, computers include, for example, laptops, desktops, and laptops equipped with a web browser, while portable terminals can include, for example, all types of handheld-based wireless communication devices such as IMT (International Mobile Telecommunication), CDMA (Code Division Multiple Access), W-CDMA (W-Code Division Multiple Access), LTE (Long Term Evolution) terminals, smartphones, and tablet PCs, as long as portability and mobility are guaranteed.

[0041] The embodiments of this disclosure will be described below in detail, with reference to the accompanying drawings, so that they can be easily implemented by a person with ordinary skill in the art to which this disclosure pertains. However, this disclosure may be embodied in several different forms and is not limited to the embodiments described herein.

[0042] Embodiments of this disclosure will be described in detail below with reference to the drawings.

[0043] Figure 1 shows the interlocking relationships of a battery management device according to one embodiment.

[0044] Referring to Figure 1, the battery management device 100 can operate in conjunction with the battery 200 and the charging element 300. On the other hand, Figure 1 only shows the components according to this embodiment. Therefore, a person with ordinary skill in the art according to this embodiment can understand that in addition to the components shown in Figure 1, other general-purpose components may be included.

[0045] The battery management device 100 can charge the battery 200 by controlling the current input from the charging element 300. Here, the charging element 300 may be a commonly used battery charger and may have various forms depending on the intended use and manner of use of the battery. The battery management device 100 can control the charging of the battery in various ways, including directly controlling such a charging element 300, transmitting necessary current and voltage information to the charging element 300, or controlling the current input from the charging element 300 along the way, and is not limited to the examples given above.

[0046] The battery 200 envisioned in this disclosure is a battery that includes lithium metal as at least a portion of its negative electrode, and may be at least one of next-generation batteries such as a lithium-sulfur battery, a lithium-metal battery, or an all-solid-state battery. In other words, the charge control method of this disclosure described below can be applied to a variety of batteries that include lithium metal as at least a portion of their negative electrode, in addition to the examples given above, and is not limited to the examples given above.

[0047] A charging control method according to one embodiment of this disclosure will be described below with reference to Figure 2.

[0048] Figure 2 is a flowchart of a charging control method according to one embodiment.

[0049] In step S210, the battery management device 100 can charge the battery 200 based on a first charge level. In step S220, the battery management device 100 responds to the fact that the charge state (State-of-Charge, SoC) of the battery 200 has reached a threshold and can charge the battery based on a second charge level higher than the first charge level. Each step will be described in more detail below.

[0050] First, the battery management device 100 can charge the battery 200 based on a first charge rate. Here, the first charge rate and the second charge rate applied after the SoC threshold is reached may be values ​​that indicate the rate at which the battery is charged, expressed as the current rate (C-rate). Specifically, the charge rate is a value calculated by dividing the charging current by the rated capacity of the battery, and its unit may be expressed as C = A / Ah. As a result, the battery management device 100 can determine the charging current to be input to the battery based on the first or second charge rate and charge the battery with that charging current in conjunction with the charging element 300.

[0051] To describe step S210 again, the battery management device 100 can charge the battery 200 at a first charge rate until the SoC reaches a threshold. According to one embodiment, the first charge rate may be a value selected based on several values ​​that can quantitatively measure the decrease in battery performance with increasing charge-discharge cycles of the battery 200, such as the remaining discharge capacity or Coulomb efficiency. Alternatively, according to one embodiment, it may be a value selected within a range in which too many dendrites are generated by the reaction of lithium metal included as at least a portion of the negative electrode.

[0052] The battery management device 100 can thus continuously measure, i.e., monitor, the SoC of the battery 200 while charging the battery 200 at a first charge level. Subsequently, the battery management device 100 can sense, through SoC monitoring, that the SoC has reached a threshold. In response to the SoC reaching the threshold, the battery management device 100 can charge the battery 200 based on a second charge level higher than the first charge level. Refer to Figure 3 to examine an example of increasing the charge level in this way.

[0053] Figure 3 is a graph showing the increase in charge rate after reaching a threshold according to one embodiment.

[0054] As shown in Figure 3, the battery management device 100 can charge the battery 200 based on a first charge rate 120 before the SoC reaches a threshold 110, and then, in response to the SoC reaching the threshold 110, charge the battery 200 based on a second charge rate 130 which is higher than the first charge rate 120. As shown in the drawing, the unit of the charge rate may be C, and the unit of the charge state may be %.

[0055] The following describes the threshold used as a criterion for increasing the charge level, and the second charge level that increases in response to reaching the threshold.

[0056] First, according to one embodiment, the threshold can be determined by analyzing the chemical reactions occurring at the negative electrode during the battery charging process and based on the SoC at the point where the proportion of the lithium metal reaction in the chemical reactions decreases to below a threshold ratio. Since lithium metal, which is included as at least a portion of the negative electrode, can cause dendrite formation through chemical reactions at the negative electrode, after the proportion of such lithium metal chemical reactions decreases, even if the charge level is increased, less dendrite formation may occur. Here, the threshold ratio can be simply set to 50%, but it can be set in various ways according to the designer's intentions. For example, the threshold ratio can be set high for rapid charging of the battery, or low for battery stability, and then the threshold can be set based on the SoC at the point where that threshold ratio is reached. In other words, the threshold ratio for determining the threshold is not limited to any value, and a variety of values ​​are possible according to the designer's intentions.

[0057] According to one embodiment, in the case of a lithium-sulfur battery, which includes lithium metal as at least a portion of the negative electrode, a threshold can be determined based on the State of Celsius (SoC) at the point where the chemical reaction at the negative electrode changes from a lithium metal reaction to a lithium-sulfur shuttle reaction. In the case of batteries that include lithium metal as at least a portion of the negative electrode, such as lithium metal batteries or all-solid-state batteries, beyond a certain SoC, the ratio of chemical reactions of other components contained in the positive electrode or electrolyte may exceed a threshold ratio, instead of the reaction by lithium metal at the negative electrode. A threshold can be determined based on the SoC at such a specific point.

[0058] Here, changes in the ratio of chemical reactions occurring at the negative electrode can be directly confirmed through various conventional methods of analyzing chemical reactions, or indirectly confirmed through changes in other values. Thus, as one embodiment of indirectly confirming changes in the ratio of chemical reactions, it is also possible to estimate such changes in the ratio of chemical reactions through the voltage at the negative electrode. Of course, changes in the voltage at the negative electrode do not necessarily occur in accordance with such changes in the ratio of chemical reactions.

[0059] According to one embodiment, the threshold that can act as a trigger for the aforementioned increase in charge level can be determined based on a profile showing the negative electrode voltage corresponding to the SoC of the battery 200. Here, the negative electrode voltage shown in the profile may have an inflection point, and thus the threshold can be determined based on the SoC corresponding to the inflection point of the profile. Here, the inflection point does not have to be an inflection point in a mathematical sense, and may be a point where the transition of the negative electrode voltage corresponding to charging temporarily fluctuates.

[0060] According to one embodiment, such an inflection point may be the point on the profile where the absolute value of the negative electrode voltage increases, then decreases, and then increases again in response to the charging of the battery 200. To examine one embodiment of such an inflection point in a lithium-sulfur battery, refer to Figure 4.

[0061] Figure 4 is a graph showing a profile of the negative electrode voltage, which is referenced to determine the threshold according to one embodiment.

[0062] Referring to Figure 4, we can see the first to third voltage graphs 401, 402, and 403. As will be explained later, the first voltage graph 401 may represent the case where the first charge level is maintained throughout the charging process of the lithium sulfur battery, the second voltage graph 402 may represent the case where a 2-1 charge level higher than the first charge level is applied in response to reaching the SoC threshold, and the third voltage graph 403 may represent the case where a 2-2 charge level higher than the first charge level is applied in response to reaching the SoC threshold. In all three graphs, as mentioned above, we can see that the absolute value of the negative electrode voltage increases, then decreases, and then increases again at the point corresponding to the threshold 110. The threshold can be determined by the SoC value at such an inflection point, or it can be selected within a specific range corresponding to the inflection point. As shown in the figure, the unit of the negative electrode voltage may be V, and the unit of the charge level may be %.

[0063] The negative electrode voltage profile shown in Figure 4 is only one example relating to a lithium-sulfur battery and can be derived differently depending on the type of battery. Therefore, the inflection points on the profile where the trend of the negative electrode voltage changes can be derived in various ways, and in some cases, there may be multiple such points. Furthermore, the formation of the inflection points may correspond to changes in the ratio of the chemical reaction described above, but is not limited to this, and embodiments in which the threshold is determined based on inflection points formed by other factors may also be included in the scope of this disclosure.

[0064] Subsequently, in response to the SoC reaching a threshold, the battery management device 100 can charge the battery 200 based on a second charge rate higher than the first charge rate. Here, the second charge rate can be selected within the range of exceeding the first charge rate and being equal to or less than the third charge rate. Here, the third charge rate may be a value corresponding to the maximum charge rate, and may be a value set to prevent adverse effects on the battery, as applying an excessively high charge rate even after reaching the threshold can have adverse effects on the battery. Such a third charge rate can be selected as the largest among candidate charge rates in which at least a portion of the remaining discharge capacity and Coulomb efficiency for the charging result applied in response to reaching the threshold falls within the normal range. In other words, the largest third charge rate can be selected as the maximum charge rate while the adverse effects on the battery, as confirmed in terms of the remaining discharge capacity and Coulomb efficiency, fall within the acceptable range. According to one embodiment, the normal range can be determined based on the remaining discharge capacity and Coulomb efficiency of a control group to which the same first charge rate was applied throughout the charging process.

[0065] As a result, the second charge level may be selected by the battery management device 100 by the administrator within a range of exceeding the first charge level and being below the third charge level, or it may be selected within that range by a predetermined algorithm that, depending on the situation, gives weight to either battery stability or rapid charging. Refer to Figure 5 to consider the case where the remaining discharge capacity and Coulomb efficiency that can be used to select such a third charge level fall within the normal range.

[0066] Figure 5 is a graph showing the remaining discharge capacity and Coulomb efficiency when the 2-1 charge rate and 2-2 charge rate are applied after reaching the threshold according to one embodiment.

[0067] Here, the remaining discharge capacity can be a value expressed in percentage terms representing the degree of discharge when the battery is connected to an open circuit, and the Coulomb efficiency can mean the ratio of charge capacity to discharge capacity. In Figure 5, the first upper graph 501-1 to the third upper graph 503-1 show the remaining discharge capacity as the number of charge cycles on the horizontal axis increases, and the corresponding value can be on the left vertical axis. Also, the first lower graph 501-2 to the third lower graph 503-2 show the Coulomb efficiency as the number of charge cycles on the horizontal axis increases, and the corresponding value can be on the right vertical axis. Furthermore, Figure 5 can be linked to the graphs in Figure 4. That is, the first upper graph 501-1 and the first lower graph 501-2, which are represented by dashed lines like an index, can correspond to the case of the first voltage graph 401 in Figure 4. That is, the first upper graph 501-1 and the first lower graph 501-2, like the first voltage graph 401, can show the remaining discharge capacity and Coulomb efficiency when the first charge rate is applied throughout the charging process. Therefore, the first upper graph 501-1 and the first lower graph 501-2 can be identified as graphs of the control group. The second upper graph 502-1 and the second lower graph 502-2, represented by dotted lines as shown in the index, correspond to the case of the second voltage graph 402 in Figure 4, and can show the remaining discharge capacity and Coulomb efficiency when the 2-1 charge rate is applied after the SoC has reached the threshold. The third upper graph 503-1 and the third lower graph 503-2, represented by solid lines as shown in the index, correspond to the case of the third voltage graph 403 in Figure 4, and can show the remaining discharge capacity and Coulomb efficiency when the 2-2 charge rate is applied after the SoC has reached the threshold. As can be seen in Figure 5, 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, do not differ significantly from the first upper graph 501-1 and the first lower graph 501-2. In such cases, the second-first charge rate and the second-second charge rate are both within the normal range and can be at least part of the candidate charge rates. Thus, from the perspective of remaining discharge capacity and Coulomb efficiency, the largest of the candidate charge rates within the normal range can be selected as the third charge rate.Naturally, embodiments that consider only one of the two factors, instead of considering both the remaining discharge capacity and the Coulomb efficiency, are also likely to fall within the scope of this disclosure.

[0068] According to one embodiment, if the battery 200 contains sulfur as at least a portion of the positive electrode, that is, if it is a lithium-sulfur battery, the first charge rate may be determined to be 0.2C and the second charge rate to be 0.5C. Such first and second charge rates may be determined by the embodiments described above.

[0069] The threshold described above may be determined based on at least one of the following: temperature, humidity, atmospheric pressure, and the state-of-health (SoH) of the battery 200, in addition to the negative electrode voltage profile or the change in the ratio of chemical reactions mentioned above. For example, if the temperature is high, changes such as an earlier appearance of an inflection point on the negative electrode voltage profile or a faster decrease in the ratio of reactions by lithium metal may occur, in which case the threshold may be set lower, and similar changes in the threshold may be observed with respect to humidity and atmospheric pressure. Also, if the SoH value is low, a large amount of lithium metal may have already been consumed, causing the ratio of reactions by lithium metal to decrease faster or an earlier appearance of an inflection point on the negative electrode voltage profile, which may result in setting a lower threshold. All situations described above are illustrative, and it is considered that the scope of this disclosure also includes cases where the opposite is true, for example, setting a higher threshold when the temperature is high or the SoH value is low, and further, cases where the threshold is determined based on at least one of the following: temperature, humidity, atmospheric pressure, and SoH, are all considered to be within the scope of this disclosure.

[0070] Furthermore, the difference between the first and second charge levels, i.e., how much the charge level should be increased, can also be determined based on at least one of temperature, humidity, atmospheric pressure, and SoH. For example, in the case of high temperatures where dendrite formation may be accelerated, or in the case of low SoH values ​​where it can be predicted that many dendrites have already formed, the second charge level may be set higher than the first charge level, but with a slightly smaller difference. All the situations described above are illustrative, and the scope of this disclosure also includes cases where the opposite is true, such as setting the second charge level higher when the temperature is high or the SoH value is low.

[0071] Alternatively, in another embodiment, the first and second charge rates can be determined over a wide range based on the remaining discharge capacity and Coulomb efficiency described above, and a combination of the first and second charge rates can be determined by further considering at least some of temperature, humidity, atmospheric pressure, and SoH. For example, in an embodiment where the first charge rate applied before reaching the threshold at which dendrite formation is likely to occur is lower than the existing rate when the SoH is low, dendrite formation can be prevented, and the second charge rate applied after reaching the threshold at which dendrite formation is unlikely to occur can be increased than the existing rate to speed up the charging process.

[0072] According to one embodiment, the battery management device 100 can refer to a table to determine a threshold, a first charge rate, and a second charge rate, taking into account temperature, humidity, atmospheric pressure, and SoH. That is, it can check the state information of the battery 200 at that time and charge the battery 200 by applying an optimized threshold, first charge rate, and second charge rate to the state information based on a table containing information on thresholds, first charge rates, and second charge rates calculated separately for temperature, humidity, atmospheric pressure, and SoH. Refer to Figure 6 to examine such an embodiment.

[0073] Figure 6 is an illustrative diagram of a table containing information regarding temperature, humidity, atmospheric pressure, and thresholds, first charge level, and second charge level according to one embodiment.

[0074] Referring to Figure 6, a table can be seen containing information on the threshold, first charge rate, and second charge rate as the temperature increases from 25°C to 28°C, when the humidity, atmospheric pressure, and SoH are 30%, 1 atmosphere, and 98%, respectively. As illustrated above, the table may be set so that the threshold and first charge rate decrease and the second charge rate increases as the temperature increases. According to one embodiment, the battery management device 100 checks the state information by measuring the temperature, humidity, and atmospheric pressure inside the cell and the SoH of the cell, then searches for the combination of temperature, humidity, atmospheric pressure, and SoH on the table that is most similar to the state information, and charges the battery 200 by applying the corresponding threshold, first charge rate, and second charge rate values. In Figure 6, for convenience, only the changes in the threshold, first charge rate, and second charge rate in response to temperature changes are shown, but the actual table may include information on the threshold, first charge rate, and second charge rate that change in various ways depending on humidity, atmospheric pressure, and SoH. Furthermore, the transitions of the threshold, first charge rate, and second charge rate according to the temperature, humidity, atmospheric pressure, and SoH shown in the table are merely examples, and embodiments in which the threshold, first charge rate, and second charge rate are set according to other transitions may also be included in the scope of this disclosure.

[0075] To illustrate the configuration of the battery management device 100, which controls the charging of a battery 200 containing lithium metal as at least a portion of its negative electrode, please refer to Figure 7.

[0076] Figure 7 shows a block diagram of a control device according to one embodiment.

[0077] In one embodiment, the battery management device 100 may include a memory 101, a processor 102, and one or more sensors 103. The battery management device 100 shown in Figure 7 only shows the components relating to this embodiment. Therefore, a person ordinary skill in the art of this embodiment will understand that other general-purpose components may be included in addition to the components shown in Figure 7. In one embodiment, the processor 102 may be included in a controller.

[0078] One or more sensors 103 may include sensors for measuring at least some of the temperature, voltage, or current used by the battery management device 100 to measure the state of the battery cells.

[0079] The processor 102 can control the overall operation of the battery management device 100 and process data and signals. The processor 102 may consist of at least one hardware unit. Alternatively, the processor 102 can operate through one or more software modules generated by executing program code stored in memory 101. Since the processor 102 can include memory, it can execute program code stored in memory to control the overall operation of the battery management device 100 and process data and signals.

[0080] The processor 102 may be configured to charge the battery based on a first charge level by executing one or more instructions, and to charge the battery based on a second charge level higher than the first charge level in response to the battery's charge state (State-of-Charge, SoC) reaching a threshold. It may also be configured to perform operations for controlling the charging of a battery that includes the aforementioned lithium metal as at least a portion of the negative electrode.

[0081] Depending on the embodiment, the battery management device 100 may additionally include a transceiver for wired / wireless communication. The battery management device 100 can communicate with an external electronic device using the transceiver. The external electronic device may be a terminal or a server. The communication technologies used by the transceiver include GSM (Global System for Mobile communication), CDMA (Code Division Multi Access), LTE (Long Term Evolution), 5G, WLAN (Wireless LAN), Wi-Fi (Wireless-Fidelity), and Bluetooth® (registered trademark). TM Possible technologies include RFID (Radio Frequency Identification), infrared communication (Infrared Data Association, IrDA), ZigBee, and NFC (Near Field Communication).

[0082] The battery management device according to the embodiment described above may include a processor, memory for storing and executing program data, permanent storage such as a disk drive, a communication port for communicating with external devices, and user interface devices such as a touch panel, keys, and buttons. A method embodied in a software module or algorithm may be stored on a computer-readable recording medium as computer-readable code or program instructions that can be executed on the processor. Here, computer-readable recording media include magnetic recording media (e.g., ROM (read-only memory), RAM (random-access memory), floppy disks, hard disks, etc.) and optical reading media (e.g., CD-ROM, DVD (Digital Versatile Disc)). Computer-readable recording media may be distributed across a network of computer systems, and computer-readable code may be stored and executed in a distributed manner. The medium may be computer-readable, stored in memory, and executed on the processor.

[0083] This embodiment may be represented by functional block configurations and diverse processing stages. Such functional blocks may be embodied by a variety of hardware and / or software configurations that perform specific functions. For example, the embodiment may employ an integrated circuit configuration such as memory, processing, logic, or look-up tables, which can perform diverse functions under the control of one or more microprocessors or other control devices. Just as the components may be executed by software programming or software elements, this embodiment includes a variety of algorithms embodied by combinations of data structures, processes, routines, or other programming configurations, which may be embodied in programming or scripting languages ​​such as C, C++, Java, or assembler. Functional aspects may be embodied by algorithms executed on one or more processors. Furthermore, this embodiment may employ prior art for electronic environment configuration, signal processing, and / or data processing. Terms such as “mechanism,” “element,” “means,” and “configuration” may be used broadly and are not limited to mechanical and physical configurations. The terms may also include the meaning of a series of software processes (routines) in conjunction with a processor, etc.

[0084] The embodiments described above are merely examples, and other embodiments may be embodied within the scope of the claims described later.

Claims

1. A method for controlling the charging of a battery, which includes lithium metal as at least a portion of the negative electrode, performed by a battery management device, A step of charging the battery based on a first charge level, The process includes: a step of charging the battery based on a second charge rate higher than the first charge rate, in response to the battery's charge state (State-of-Charge, SoC) reaching a threshold; Charging control method.

2. The threshold is determined based on a profile showing the voltage of the negative electrode corresponding to the SoC of the battery. The charging control method according to claim 1.

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 profile.

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

5. The threshold is determined based on at least one of temperature, humidity, atmospheric pressure, and state-of-health (SoH). The charging control method according to claim 2.

6. The threshold is determined by analyzing the chemical reactions that occur at the negative electrode during the charging process of the battery, and based on the SoC at the point where the proportion of the lithium metal reaction in the chemical reactions decreases to below the threshold ratio. The charging control method according to claim 1.

7. The difference between the first charge level and the second charge level is determined based on at least one of temperature, humidity, atmospheric pressure, and SoH. The charging control method according to claim 1.

8. The second charge level is selected within the range of exceeding the first charge level and being equal to or less than the third charge level. The charging control method according to claim 1.

9. The third charge level is selected as the largest of the candidate charge levels in which at least a portion of the remaining discharge capacity and Coulomb efficiency for the charge result applied in response to reaching the threshold falls within the normal range. The charging control method according to claim 8.

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

11. A computer-readable non-temporary recording medium that stores a program for causing a computer to execute the charging control method described in any one of claims 1 to 10.

12. A battery management device for controlling the charging of a battery in which lithium metal is included as at least a part of the negative electrode, One or more sensors, Processor and Includes memory for storing one or more instructions, A battery management system comprising a processor configured to charge the battery based on a first charge rate by issuing one or more instructions, and to charge the battery based on a second charge rate higher than the first charge rate in response to the State-of-Charge (SoC) of the battery reaching a threshold.

13. The threshold is determined based on a profile showing the voltage of the negative electrode corresponding to the SoC of the battery. The battery management system according to claim 12.

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 profile.

15. The threshold is determined based on the profile, on the SoC corresponding to the inflection point where the voltage of the negative electrode increases, then decreases, and then increases again in response to the charging of the battery. The battery management system according to claim 14.

16. The threshold is determined based on at least one of temperature, humidity, atmospheric pressure, and state-of-health (SoH). The battery management system according to claim 13.

17. The threshold is determined by analyzing the chemical reactions that occur at the negative electrode during the charging process of the battery, and based on the SoC at the point where the proportion of the lithium metal reaction in the chemical reactions decreases to below the threshold ratio. The battery management system according to any one of claims 12 to 16.

18. The difference between the first charge level and the second charge level is determined based on at least one of temperature, humidity, atmospheric pressure, and SoH. The battery management system according to claim 12.

19. The second charge level is selected within the range of exceeding the first charge level and being equal to or less than the third charge level. The battery management system according to claim 12.

20. The third charge level is selected as the largest of the candidate charge levels in which at least a portion of the remaining discharge capacity and Coulomb efficiency for the charge result applied in response to reaching the threshold falls within the normal range. The battery management system according to claim 19.

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

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