Battery management device and method, and battery pack including the battery management device

Abstract

A battery management device according to an embodiment of the present invention may include: a measuring unit configured to measure a charging voltage, a charging current, a discharging voltage, and a discharging current during charging and discharging of a battery according to a preconfigured charging C-rate and a preconfigured discharging C-rate; and a control unit configured to receive information about the voltage and current of the battery from the measuring unit, calculate a charging resistance for each voltage of the battery based on the charging voltage and the charging current, calculate a discharging resistance for each voltage of the battery based on the discharging voltage and the discharging current, calculate a resistance ratio between the charging resistance and the discharging resistance for each voltage of the battery, and set a discharge C-rate of the battery based on the resistance ratio calculated for each voltage of the battery.

Description

Technical Field

[0001] This application claims the benefit of priority to Korean Patent Application No. 10-2021-0018521, filed in Korea on February 9, 2021, the disclosure of which is incorporated herein by reference.

[0002] This disclosure relates to a battery management device and method, and more specifically, to a battery management device and method capable of improving the performance efficiency of a battery. Background Technology

[0003] Recently, demand for portable electronic products such as laptops, cameras, and mobile phones has increased dramatically, and electric vehicles, energy storage batteries, robots, and satellites have also seen significant development. Therefore, high-performance batteries that allow for repeated charging and discharging are being actively researched.

[0004] Currently available commercial batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium batteries. Among them, lithium batteries have attracted much attention because they have almost no memory effect compared to nickel-based batteries, and also have a very low self-discharge rate and high energy density.

[0005] Furthermore, recent research has focused on negative electrode active materials that combine two or more materials to achieve various goals, such as high battery capacity and high output. However, due to the different charge / discharge efficiencies and reaction voltage ranges of the two or more materials, battery degradation occurs due to the rapid deterioration of the material with the relatively lower charge / discharge efficiency. Therefore, it is necessary to develop a method to improve the lifespan of batteries that include negative electrode active materials that combine two or more materials. Summary of the Invention

[0006] Technical issues

[0007] This disclosure aims to address the problems of the prior art, and therefore aims to provide a battery management device and method that can improve battery performance efficiency and lifespan by adjusting the discharge C rate.

[0008] These and other objects and advantages of this disclosure will become apparent from the following detailed description and will become more apparent from exemplary embodiments thereof. Furthermore, it will be readily understood that the objects and advantages of this disclosure can be achieved by the means set forth in the appended claims and combinations thereof.

[0009] Technical solution

[0010] A battery management device according to one aspect of this disclosure may include: a measurement unit configured to measure a charging voltage, a charging current, a discharging voltage, and a discharging current during charging and discharging of a battery according to a preset charging C-rate and a preset discharging C-rate; and a control unit configured to receive information about the voltage and current of the battery from the measurement unit, calculate a charging resistance of the battery at each voltage based on the charging voltage and the charging current, calculate a discharging resistance of the battery at each voltage based on the discharging voltage and the discharging current, calculate a resistance ratio between the charging resistance and the discharging resistance at each voltage of the battery, and set a discharging C-rate of the battery based on the resistance ratio calculated for each voltage of the battery.

[0011] The control unit can be configured to calculate the resistance ratio for each voltage by calculating the ratio of the charging resistance to the discharging resistance for each voltage of the battery.

[0012] The control unit can be configured to select a maximum resistance ratio among the resistance ratios calculated for each voltage of the battery, and adjust the discharge C rate based on the selected maximum resistance ratio.

[0013] The control unit can be configured to set the discharge C rate to the preset discharge C rate when the maximum resistance ratio is less than the reference value.

[0014] The control unit can be configured to change the discharge C rate to be different from the preset discharge C rate when the maximum resistance ratio is equal to or greater than the reference value.

[0015] The control unit can be configured to change the discharge C rate to a rate greater than the preset charging C rate of the battery.

[0016] The control unit can be configured to increase the discharge C rate to correspond to the maximum resistance ratio, and set the increased discharge C rate as the discharge C rate of the battery.

[0017] The control unit can be configured to increase the discharge C rate based on the maximum resistance ratio and the battery characteristic factor corresponding to the battery.

[0018] The battery can be configured to include a composite negative electrode active material in which graphite and silicon are mixed.

[0019] The measuring unit can be configured to measure the charging voltage and the charging current during the charging of the battery at a constant current at the preset charging rate C, and to measure the discharging voltage and the discharging current during the discharging of the battery at a constant current at the preset discharging rate C.

[0020] A battery pack according to another aspect of this disclosure may include the battery management device described in one aspect of this disclosure.

[0021] A battery management method according to another aspect of this disclosure may include: a measurement step, which measures a charging voltage, a charging current, a discharging voltage, and a discharging current during charging and discharging of a battery according to a preset charging C rate and a preset discharging C rate; a charging resistance calculation step, which calculates the charging resistance of the battery at each voltage based on the charging voltage and the charging current; a discharging resistance calculation step, which calculates the discharging resistance of the battery at each voltage based on the discharging voltage and the discharging current; a resistance ratio calculation step, which calculates the resistance ratio between the charging resistance and the discharging resistance at each voltage of the battery; and a discharging C rate setting step, which sets the discharging C rate of the battery based on the resistance ratio calculated for each voltage of the battery.

[0022] Beneficial effects

[0023] According to one aspect of this disclosure, the battery management device has the advantage of improving battery performance efficiency and extending battery life by adjusting the battery's discharge rate (C).

[0024] The effects of this disclosure are not limited to those described above; other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims. Attached Figure Description

[0025] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, serve to provide a further understanding of the technical features of the present disclosure; therefore, the present disclosure is not to be construed as limited to the illustrations.

[0026] Figure 1 This is a schematic diagram illustrating a battery management device according to one embodiment of the present disclosure.

[0027] Figure 2 This is a diagram illustrating an exemplary configuration of a battery pack including a battery management device according to one embodiment of the present disclosure.

[0028] Figure 3 This is a schematic diagram showing the charging resistance and discharging resistance of a battery and a reference cell according to one embodiment of the present disclosure.

[0029] Figure 4 This is a schematic diagram illustrating the charging resistance and discharging resistance of a battery according to one embodiment of the present disclosure, wherein a discharge rate C is provided in the battery.

[0030] Figure 5 This is a schematic diagram illustrating the first capacity retention rate and the second capacity retention rate of a battery according to one embodiment of the present disclosure.

[0031] Figure 6 This is a schematic diagram illustrating the first and second coulombic efficiencies of a battery according to one embodiment of the present disclosure.

[0032] Figure 7 This is a schematic diagram illustrating a battery management method according to another embodiment of the present disclosure. Detailed Implementation

[0033] It should be understood that the terms used in the specification and appended claims should not be construed as limited to their general and dictionary meanings, but rather are interpreted according to their meanings and concepts corresponding to the technical aspects of this disclosure, based on the principle that inventors are allowed to make appropriate definitions of the terms to obtain the best interpretation.

[0034] Therefore, the description presented herein is merely a preferred embodiment for illustrative purposes and is not intended to limit the scope of the disclosure. It should be understood that other equivalents and modifications may be made to this disclosure without departing from its scope.

[0035] Furthermore, in the description of this disclosure, detailed descriptions of relevant known elements or functions are omitted where such detailed descriptions would obscure the key subject matter of this disclosure.

[0036] Ordinal terms such as “first” and “second” can be used to distinguish one element from another among various elements, but are not intended to limit elements by means of terms.

[0037] Throughout this specification, when a section is referred to as “containing” or “including” any element, it means that the section may additionally include other elements, without excluding other elements, unless otherwise specifically stated.

[0038] Furthermore, throughout the specification, when one part is referred to as being "connected" to another part, it is not limited to the case where they are "directly connected," but also includes the case where they are "indirectly connected" by inserting another element between them.

[0039] The preferred embodiments of this disclosure will be described in detail below with reference to the accompanying drawings.

[0040] Figure 1This is a schematic diagram illustrating a battery management device 100 according to one embodiment of the present disclosure.

[0041] Figure 2 This is a diagram illustrating an exemplary configuration of a battery pack 1 including a battery management device 100 according to one embodiment of the present disclosure.

[0042] refer to Figure 1 According to one embodiment of the present disclosure, a battery management device 100 may include a measurement unit 110 and a control unit 120.

[0043] The measurement unit 110 can be configured to measure the charging voltage, charging current, discharging voltage, and discharging current during the charging and discharging of the battery B according to a preset charging rate C and a preset discharging rate C.

[0044] The preset charging C rate and the preset discharging C rate can be the first preset C rate or the C rate previously preset by the control unit 120. For example, the preset charging C rate can be preset to 0.03C, and the preset discharging C rate can be preset to 0.03C.

[0045] Here, battery B refers to a physically separable, independent cell, which includes a negative terminal and a positive terminal. For example, a lithium-ion battery or a lithium polymer battery can be considered battery B.

[0046] Preferably, battery B expresses capacity in the bottom region of SOC (State of Charge) and may further include an additional active material that, compared to the basic active material, exhibits large resistive hysteresis between resistance and voltage and low charge and discharge efficiency. That is, battery B may include a composite negative electrode active material in which a basic active material and an additional active material are mixed. For example, battery B may be configured to include a composite negative electrode active material mixed with graphite and silicon. Here, graphite may be the basic active material, and silicon may be the additional active material.

[0047] The measurement unit 110 can be configured to measure the charging voltage and charging current during the charging of battery B at a preset charging rate C with a constant current, and to measure the discharging voltage and discharging current during the discharging of battery B at a preset discharging rate C with a constant current.

[0048] Specifically, in Figure 2In this embodiment, the measurement unit 110 can be connected to a first sensing line SL1, a second sensing line SL2, and a third sensing line SL3. The measurement unit 110 can be connected to the positive terminal of the battery B via the first sensing line SL1, and can be connected to the negative terminal of the battery B via the second sensing line SL2. Furthermore, the measurement unit 110 can measure the voltage of the battery B by calculating the difference between the voltage measured via the first sensing line SL1 and the voltage measured via the second sensing line SL2. During charging of the battery B at a charging rate C, the measurement unit 110 can measure the charging voltage of the battery B via the first sensing line SL1 and the second sensing line SL2. Conversely, during discharging of the battery B at a discharging rate C, the measurement unit 110 can measure the discharging voltage of the battery B via the first sensing line SL1 and the second sensing line SL2.

[0049] Furthermore, the measurement unit 110 can be connected to the current measurement unit via the third sensing line SL3 to measure the charging current and discharging current of the battery B. Here, the battery B can be charged at a constant current at a charging rate C or discharged at a constant current at a discharging rate C.

[0050] For example, the current measurement unit can be a current sensor or shunt resistor positioned on the charging and discharging paths of battery B to measure the charging and discharging currents of battery B. Here, the charging and discharging paths of battery B can be high-current paths, in which charging current is applied to battery B or discharging current is output from battery B. Figure 2 In this embodiment, the current measuring unit can be connected between the negative terminal of battery B and the negative terminal P- of battery pack 1 in the charging and discharging path of battery B. However, it should be noted that the current measuring unit can also be connected between the positive terminal of battery B and the positive terminal P+ of battery pack 1, as long as the current measuring unit is in the charging and discharging path of battery B.

[0051] The control unit 120 can be configured to receive information about the voltage and current of the battery B from the measurement unit 110.

[0052] For example, in Figure 2 In this embodiment, the control unit 120 and the measurement unit 110 can be connected to enable communication. The measurement unit 110 can output information related to the measured charging voltage, charging current, discharging voltage, and discharging current to the control unit 120, and the control unit 120 can receive information about the voltage and current of battery B from the measurement unit 110.

[0053] The control unit 120 can be configured to calculate the charging resistance of battery B at each voltage based on the charging voltage and charging current.

[0054] Specifically, the control unit 120 can calculate the charging resistance for each charging voltage by using Ohm's law to calculate the ratio of charging voltage to charging current. For example, since battery B is charged at a constant current at a charging rate C, the control unit 120 can calculate the charging resistance for each charging voltage by calculating the rate of change of resistance relative to current.

[0055] The control unit 120 can be configured to calculate the discharge resistance of battery B at each voltage based on the discharge voltage and discharge current.

[0056] Specifically, the control unit 120 can calculate the discharge resistance for each discharge voltage in the same way as the method for calculating the charging resistance, by using Ohm's law to calculate the ratio of discharge voltage to discharge current.

[0057] Figure 3 This is a schematic diagram showing the charging resistance and discharging resistance of a battery B and a reference cell according to one embodiment of the present disclosure.

[0058] exist Figure 3 In one embodiment, the first charging resistor BC1 may be the charging resistor of battery B for each voltage calculated by the control unit 120, and the first discharging resistor BD1 may be the discharging resistor of battery B for each voltage calculated by the control unit 120.

[0059] Additionally, refer to Figure 3 The reference cell can be a cell that includes one type of negative electrode active material (different from battery B). For example, the reference cell can be a cell that includes graphite as the negative electrode active material. If the charging resistance RC and discharging resistance RD of the reference cell are compared with the first charging resistance BC1 and the first discharging resistance BD1 of battery B, it can be found that the resistance hysteresis of battery B is greater than that of the reference cell. This may be because battery B includes different types of negative electrode active materials (e.g., graphite and silicon). Since graphite and silicon included in battery B have different SOC regions that express capacity, the resistance hysteresis of battery B can be greater than that of the reference cell in the low-voltage region (bottom SOC region) where silicon capacity is expressed.

[0060] The control unit 120 can be configured to calculate the resistance ratio between the charging resistance and the discharging resistance of the battery B at each voltage.

[0061] Specifically, the control unit 120 can calculate the resistance ratio of each voltage by calculating the ratio of the charging resistance to the discharging resistance of each voltage. For example, the control unit 120 can calculate the resistance ratio of each voltage by calculating "charging resistance ÷ discharging resistance".

[0062] For example, in Figure 3In this implementation, the discharge resistance of battery B at 3.3V can be RB2, and the charging resistance can be RB1. The control unit 120 can calculate the resistance ratio at 3.3V by calculating "RB1 ÷ RB2".

[0063] In addition, Figure 3 In this implementation, the resistance ratio of the reference cell at 3.3V can be "RC1÷RC2". That is, since the reference cell has a smaller resistive hysteresis than battery B, the resistance ratio of the reference cell can be smaller than that of battery B for the same voltage (3.3V).

[0064] The control unit 120 can be configured to set the discharge rate C of battery B based on the resistance ratio calculated for each voltage of battery B.

[0065] Specifically, the control unit 120 can change the preset discharge rate C of battery B based on the calculated resistance ratio. Preferably, the control unit 120 can increase the discharge rate C based on the calculated resistance ratio. In this case, when battery B discharges at the increased discharge rate C, the potential of the positive electrode decreases in the latter half of the discharge (low voltage region, bottom of SOC region) due to the accumulation of positive electrode overvoltage. That is, the positive electrode potential decreases in the region where the capacity of silicon is demonstrated. Furthermore, since the discharge resistance of battery B increases as the positive electrode potential decreases in the latter half of the discharge, the resistance hysteresis of battery B decreases. That is, the resistance hysteresis of battery B can be reduced by increasing the discharge rate C by the control unit 120.

[0066] Figure 4 This is a schematic diagram illustrating the charging resistance and discharging resistance of a battery B according to one embodiment of the present disclosure, wherein a discharge rate C is provided in the battery B.

[0067] exist Figure 4 In this embodiment, the second charging resistor BC2 can be a charging resistor for each voltage of the battery B with a changed discharge rate C, and the second discharging resistor BD2 can be a discharging resistor for each voltage of the battery B with a changed discharge rate C. The first charging resistor BC1 and... Figure 3 The first charging resistor BC1 is the same, and the first discharging resistor BD1 is the same as... Figure 3 The first discharge resistance BD1 is the same. That is, the first charging resistance BC1 and the first discharging resistance BD1 can be the resistance curves of battery B before the discharge rate C changes.

[0068] refer to Figure 4When the discharge rate C is set according to the resistance ratio, it can be observed that the resistance hysteresis of battery B decreases compared to the preset discharge rate C. For example, before changing the discharge rate C of battery B, the resistance ratio of battery B at 3.3V could be "RB1÷RB2". On the other hand, after changing the discharge rate C of battery B, the resistance ratio of battery B at 3.3V could be "RB3÷RB4". After setting the discharge rate C in the control unit 120, it can be observed that the resistance hysteresis of battery B decreases significantly.

[0069] That is, the battery management device 100 according to one embodiment of the present disclosure has the advantage of reducing the resistive hysteresis of the battery B by appropriately setting the discharge rate C of the battery B, which includes a composite negative electrode active material containing two or more types of active materials.

[0070] Therefore, the discharge C rate set by the battery management device 100 can be set to the discharge C rate used during the operation of battery B. That is, since the optimal discharge C rate is set for battery B, the performance efficiency of battery B can be improved.

[0071] Additionally, the control unit 120 disposed in the battery management device 100 may optionally include processors, application-specific integrated circuits (ASICs), other chipsets, logic circuits, registers, communication modems, data processing devices, etc., known in the art, to execute the various control logics disclosed herein. Furthermore, when the control logic is implemented in software, the control unit 120 may be implemented as a set of program modules. In this case, the program modules may be stored in memory and executed by the control unit 120. The memory may be located internally or externally to the control unit 120 and may be connected to the control unit 120 by various well-known methods.

[0072] Furthermore, the battery management device 100 may further include a storage unit 130. The storage unit 130 may store data required for the operation and function of each component of the battery management device 100, data generated during the execution of operations or functions, etc. The type of storage unit 130 is not particularly limited, as long as it is a known information storage means capable of recording, erasing, updating, and retrieving data. As an example, the information storage means may include RAM, flash memory, ROM, EEPROM, registers, etc. In addition, the storage unit 130 may store program code that defines processes executable by the control unit 120.

[0073] For example, the storage unit 130 can store the charging current, charging voltage, discharging current, and discharging voltage of battery B as measured by the measurement unit 110. Additionally, the storage unit 130 can store preset charging rate C and preset discharging rate C of battery B.

[0074] The resistive hysteresis and performance efficiency of battery B will be described below.

[0075] Figure 5 This is a schematic diagram illustrating the first capacity retention rate CR1 and the second capacity retention rate CR2 of battery B according to one embodiment of the present disclosure.

[0076] Specifically, Figure 5 The implementation is illustrated by a graph showing the first capacity retention rate CR1 of battery B before changing and setting the discharge rate C, and the second capacity retention rate CR2 of battery B after changing and setting the discharge rate C. Here, the capacity retention rate can be the ratio of the capacity in the current cycle to the capacity in the initial cycle. That is, the capacity retention rate can be the ratio between the maximum capacity at the beginning of life (BOL) state and the current maximum capacity. Generally, since battery B degrades with increasing cycles, the capacity retention rate decreases with increasing cycles.

[0077] refer to Figure 5 From cycle 0 to cycle 200, the first capacity retention rate CR1 and the second capacity retention rate CR2 of battery B can be substantially similar. However, starting from cycle 200, the first capacity retention rate CR1 of battery B may decrease rapidly compared to the second capacity retention rate CR2. Since the resistive hysteresis of battery B is reduced by changing the discharge rate C of battery B, the second capacity retention rate CR2 of battery B can be maintained. Therefore, the control unit 120 can improve the performance efficiency of battery B by changing and setting the discharge rate C of battery B.

[0078] Figure 6 This is a schematic diagram illustrating the first coulombic efficiency CE1 and the second coulombic efficiency CE2 of battery B according to one embodiment of the present disclosure.

[0079] Specifically, Figure 6 The implementation is illustrated by a graph showing the first coulombic efficiency CE1 of battery B before changing and setting the discharge rate C, and the second coulombic efficiency CE2 of battery B after changing and setting the discharge rate C. Here, coulombic efficiency refers to the ratio of the capacity of the current cycle to the capacity of the previous cycle.

[0080] refer to Figure 6 From cycle 0 to cycle 200, the first coulombic efficiency CE1 and the second coulombic efficiency CE2 of battery B can have essentially similar forms. For example, the coulombic efficiency can increase from cycle 0 to cycle 140, and can gradually decrease from cycle 140 onwards.

[0081] However, starting from the 200th cycle, the first coulombic efficiency CE1 of battery B may decrease rapidly compared to the second coulombic efficiency CE2. Since the resistive hysteresis of battery B decreases by changing the discharge rate C of battery B, the second coulombic efficiency CE2 of battery B can be maintained. Therefore, the control unit 120 can improve the performance efficiency of battery B by changing the discharge rate C of battery B.

[0082] The following describes a specific implementation of setting the discharge rate C of battery B based on the resistance ratio calculated by control unit 120.

[0083] The control unit 120 can be configured to calculate the resistance ratio of each voltage by calculating the ratio of the charging resistance to the discharging resistance of each voltage of the battery B.

[0084] exist Figure 3 In this implementation, the control unit 120 can calculate the resistance ratio of each voltage by calculating the ratio of the first charging resistor BC1 to the first discharging resistor BD1. For example, the control unit 120 can calculate the resistance ratio of 3.3V by calculating "RB1 ÷ RB2".

[0085] The control unit 120 can be configured to select the maximum resistance ratio among the resistance ratios calculated for each voltage of battery B.

[0086] exist Figure 3 In one implementation, the control unit 120 can select the maximum resistance ratio with the highest value from the calculated resistance ratios after calculating the resistance ratio for each voltage.

[0087] Furthermore, the control unit 120 can be configured to adjust the discharge C rate based on the selected maximum resistance ratio.

[0088] Specifically, when the maximum resistance hysteresis (maximum resistance ratio) of battery B is equal to or greater than the reference value, the control unit 120 can change the discharge rate C of battery B. That is, when the maximum resistance ratio is less than the reference value, the control unit 120 can maintain the discharge rate C of battery B at a preset discharge rate C, and will only change the discharge rate C of battery B when the maximum resistance ratio is equal to or greater than the reference value.

[0089] For example, when the maximum resistance ratio is less than a reference value, the control unit 120 can be configured to set the discharge C rate to a preset discharge C rate. Conversely, when the maximum resistance ratio is equal to or greater than the reference value, the control unit 120 can be configured to change the discharge C rate to be different from the preset discharge C rate.

[0090] Preferably, the control unit 120 can be configured to increase the discharge C rate to correspond to the maximum resistance ratio, and set the increased discharge C rate as the discharge C rate of battery B.

[0091] Here, the control unit 120 can be configured to change the discharge rate C to a rate greater than the preset charging rate C of the battery B.

[0092] As described above, if the discharge rate C increases to be greater than the charging rate C, the positive electrode potential will decrease in the region representing the capacity of the silicon included in battery B due to the accumulation of positive electrode overvoltage. Therefore, as battery B discharges at a discharge rate C that is greater than the charging rate C, the resistance hysteresis of battery B will decrease.

[0093] Specifically, the control unit 120 can be configured to increase the discharge rate C based on the maximum resistance ratio and the battery B characteristic factor corresponding to battery B. For example, the control unit 120 can set the discharge rate C according to the following formula.

[0094] [formula]

[0095] DCm = DCn × Max × α

[0096] Here, DCm is the discharge rate C set according to the formula, and DCn is the preset discharge rate C. Furthermore, Max is the maximum resistivity ratio, and α is the battery characteristic factor B.

[0097] For example, the characteristic factor (α) of battery B can be set based on the design specifications of battery B. As a specific embodiment, the characteristic factor (α) of battery B can be a variable, which can be set according to the positive electrode capacity load, the content of conductive material, the type of positive electrode material, the type of negative electrode material, the number of moles of electrolyte salt, etc. of battery B.

[0098] For example, the positive electrode capacity load of battery B is 5mA / cm. 2 In this case, the characteristic factor (α) of battery B can be set to a number less than 1.

[0099] If the discharge C rate (DCm) set according to the formula is less than or equal to the charging C rate, the battery B characteristic factor (α) can be adjusted. Furthermore, in order to make the calculated discharge C rate greater than the charging C rate, the control unit 120 can recalculate the discharge C rate based on the adjusted battery B characteristic factor (α).

[0100] The battery management device 100 according to this disclosure can be applied to a BMS (Battery Management System). That is, the BMS according to this disclosure may include the battery management device 100 described above. In this configuration, at least some components of the battery management device 100 can be implemented by supplementing or adding functions included in the configuration of a conventional BMS. For example, the measurement unit 110, the control unit 120, and the storage unit 130 can be implemented as components of the BMS.

[0101] Furthermore, the battery management device 100 according to this disclosure can be disposed in the battery pack 1. That is, the battery pack 1 according to this disclosure may include the aforementioned battery management device 100 and one or more batteries B. In addition, the battery pack 1 may further include electrical devices (relays, fuses, etc.) and a housing.

[0102] For example, Figure 2 This is a diagram schematically illustrating an exemplary configuration of a battery pack 1 including a battery management device 100. (See reference...) Figure 2 The battery pack 1 may include battery B, current measurement unit and battery management device 100.

[0103] The charging and discharging unit 200 may be included in the battery pack 1 and may be electrically connected to the electrode terminals of the battery pack 1. Figure 2 In one embodiment, the charging and discharging unit 200 can be connected to the positive terminal (P+) and the negative terminal (P-) of the battery pack 1.

[0104] When battery B is charged by charging and discharging unit 200, measuring unit 110 can measure the charging current and charging voltage of battery B. Furthermore, when battery B is discharged by charging and discharging unit 200, measuring unit 110 can measure the discharging current and discharging voltage of battery B.

[0105] For example, the charging and discharging unit 200 can fully charge the battery B from 0% to 100% of the SOC, and can fully discharge the battery B from 100% to 0% of the SOC.

[0106] Figure 7 This is a schematic diagram illustrating a battery management method according to another embodiment of the present disclosure.

[0107] Preferably, each step of the battery management method can be performed by the battery management device 100. It should be noted below that content repeated from the previously described content will be omitted or briefly described.

[0108] refer to Figure 7The battery management method includes a measurement step (S100), a charging resistance calculation step (S200), a discharging resistance calculation step (S300), a resistance ratio calculation step (S400), and a discharge C rate setting step (S500).

[0109] The measurement step (S100) is a step of measuring the charging voltage, charging current, discharging voltage and discharging current during the charging and discharging process of battery B according to a preset charging rate C and a preset discharging rate C, and can be executed by the measurement unit 110.

[0110] Preferably, the measuring unit 110 can measure the charging voltage and charging current during the charging process of battery B at a preset charging rate C. Furthermore, the measuring unit 110 can measure the discharging voltage and discharging current during the discharging process of battery B at a preset discharging rate C.

[0111] The charging resistance calculation step (S200) is a step of calculating the charging resistance of battery B for each voltage based on the charging voltage and charging current, and can be executed by the control unit 120.

[0112] For example, the control unit 120 can calculate the charging resistance by calculating the ratio of charging voltage to charging current.

[0113] The discharge resistance calculation step (S300) is a step of calculating the discharge resistance of battery B for each voltage based on the discharge voltage and discharge current, and can be executed by the control unit 120.

[0114] For example, the control unit 120 can calculate the discharge resistance by calculating the ratio of discharge voltage to discharge current.

[0115] In the above text, although according to Figure 7 The implementation shows that the discharge resistance calculation step (S300) is performed after the charging resistance calculation step (S200), but it should be understood that the discharge resistance calculation step (S300) can be performed first, and then the charging resistance calculation step (S200) can be performed.

[0116] The resistance ratio calculation step (S400) is a step of calculating the resistance ratio between the charging resistance and the discharging resistance for each voltage of battery B, and can be executed by the control unit 120.

[0117] Specifically, for each voltage, the control unit 120 can calculate the resistance ratio by calculating the ratio of the charging resistance to the discharging resistance. For example, in Figure 3 In one implementation, the control unit 120 can calculate the resistance ratio of 3.3V by calculating “RB1÷RB2”.

[0118] The discharge C rate setting step (S500) is a step of setting the discharge C rate of battery B based on the resistance ratio calculated for each voltage of battery B, and can be executed by control unit 120.

[0119] Specifically, the control unit 120 can select the maximum resistance ratio from a plurality of resistance ratios calculated for each voltage of battery B. Furthermore, if the selected maximum resistance ratio is equal to or greater than a reference value, the control unit 120 can change the discharge rate C of battery B based on the selected maximum resistance ratio, the characteristic factor of battery B, and a preset discharge rate C.

[0120] Preferably, the control unit 120 can improve the performance efficiency of battery B by increasing the discharge rate C of battery B, so that the discharge rate C of battery B is greater than the charging rate C.

[0121] The embodiments described above can be implemented not only by devices and methods, but also by a program or a recording medium that implements functions corresponding to the construction of the embodiments of this disclosure. Such a program or recording medium can be readily implemented by those skilled in the art based on the description of the embodiments above.

[0122] This disclosure has been described in detail. However, it should be understood that while the detailed description and specific embodiments illustrate preferred embodiments of this disclosure, they are given by way of illustration only, as various variations and modifications within the scope of this disclosure will become apparent to those skilled in the art from the detailed description.

[0123] Furthermore, those skilled in the art can make many substitutions, modifications and alterations to the present disclosure without departing from its technical aspects, and the present disclosure is not limited to the above-described embodiments and drawings. Each embodiment can be selectively combined in part or in whole to achieve various variations.

[0124] (See attached image labels)

[0125] 1: Battery pack

[0126] 100: Battery Management Device

[0127] 110: Measurement Unit

[0128] 120: Control Unit

[0129] 130: Storage unit

[0130] 200: Charging and discharging unit

Claims

1. A battery management device, the battery management device comprising: The measurement unit is configured to measure the charging voltage, charging current, discharging voltage, and discharging current during the charging and discharging of the battery according to a preset charging rate C and a preset discharging rate C. as well as A control unit is configured to receive information related to the voltage and current of the battery from the measuring unit, calculate the charging resistance for each voltage of the battery based on the charging voltage and the charging current, calculate the discharging resistance for each voltage of the battery based on the discharging voltage and the discharging current, calculate the resistance ratio between the charging resistance and the discharging resistance for each voltage of the battery, and set the discharge rate C of the battery based on the resistance ratio calculated for each voltage of the battery. The control unit is configured to change the discharge C rate to a rate greater than the preset discharge C rate when the maximum resistance ratio is equal to or greater than the reference value.

2. The battery management device according to claim 1, in, The control unit is configured to select the maximum resistance ratio among the resistance ratios calculated for each voltage of the battery, and to adjust the discharge C rate based on the selected maximum resistance ratio.

3. The battery management device according to claim 2, in, The control unit is configured to set the discharge C rate to the preset discharge C rate when the maximum resistance ratio is less than the reference value.

4. The battery management device according to claim 3, in, The control unit is configured to change the discharge C rate to a rate greater than the preset charging C rate of the battery.

5. The battery management device according to claim 2, in, The control unit is configured to increase the discharge C rate to correspond to the maximum resistance ratio, and to set the increased discharge C rate as the discharge C rate of the battery.

6. The battery management device according to claim 5, in, The control unit is configured to increase the discharge C rate based on the maximum resistance ratio and the battery characteristic factor corresponding to the battery.

7. The battery management device according to claim 1, in, The battery is configured to include a composite negative electrode active material, wherein a basic active material and an additional active material are mixed in the composite negative electrode active material.

8. The battery management device according to claim 7, wherein, The basic active material is graphite, and the additional active material is silicon.

9. The battery management device according to claim 1, in, The measuring unit is configured to measure the charging voltage and the charging current during the charging of the battery at a constant current at the preset charging rate C, and to measure the discharging voltage and the discharging current during the discharging of the battery at a constant current at the preset discharging rate C.

10. A battery pack comprising a battery management device according to any one of claims 1 to 9.

11. A battery management method, the battery management method comprising: The measurement steps involve measuring the charging voltage, charging current, discharging voltage, and discharging current during the charging and discharging process of the battery according to a preset charging rate C and a preset discharging rate C. The charging resistance calculation step calculates the charging resistance for each voltage of the battery based on the charging voltage and the charging current. The discharge resistance calculation step calculates the discharge resistance for each voltage of the battery based on the discharge voltage and the discharge current. The resistance ratio calculation step calculates the resistance ratio between the charging resistor and the discharging resistor for each voltage of the battery; and The discharge C-rate setting step sets the discharge C-rate of the battery based on the resistance ratio calculated for each voltage of the battery. Specifically, when the maximum resistance ratio is equal to or greater than the reference value, the discharge C rate is changed to be greater than the preset discharge C rate.

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