Apparatus and method for managing battery

Abstract

An apparatus for managing a battery, according to an embodiment of the present invention, comprises: a measurement unit configured to measure the voltage of a battery charged while repeating charging periods and rest periods; and a control unit configured to calculate the resistance corresponding to each of a plurality of rest periods, generate a first profile indicating a correlation between the SOC of the battery and the resistance, divide an SOC range of the first profile into a plurality of unit sections, and calculate a total resistance of the battery on the basis of reference resistances and weights corresponding to the plurality of unit sections.

Description

Battery management device and method

[0001] This application claims priority to Korean Patent Application No. 10-2024-0010153, filed on January 23, 2024, the entire contents of which are disclosed in the specification and drawings of the said application are incorporated herein by reference.

[0002] The present invention relates to a battery management device and method, and more particularly, to a battery management device and method for determining the state of a battery based on the resistance of the battery.

[0003] Recently, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has rapidly increased, and the development of electric vehicles, energy storage batteries, robots, and satellites has been in full swing, research into high-performance batteries capable of repeated charging and discharging is actively being conducted.

[0004] Currently commercialized batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium batteries. Among these, lithium batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based batteries.

[0005] While extensive research is being conducted on these batteries to improve capacity and density, improving lifespan and safety is also crucial. To improve battery safety, technology is required to accurately diagnose the current battery condition.

[0006] The present invention has been devised to solve the above problems, and its purpose is to provide a battery management device and method that derive a battery status indicator used to determine the status of a battery based on the resistance of the battery.

[0007] Other objects and advantages of the present invention can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0008] According to one aspect of the present invention, a measuring unit configured to measure the voltage of a battery being charged by repeating a charger and a rest period; and a control unit configured to calculate a resistance corresponding to each of a plurality of rest periods, generate a first profile indicating a correspondence between the SOC and the resistance of the battery, divide the SOC section of the first profile into a plurality of unit sections, and calculate a total resistance of the battery based on a weight and a reference resistance corresponding to each of the plurality of unit sections.

[0009] The control unit may be configured to calculate the total resistance for the SOC section and the unit resistance for each of the plurality of unit sections, and to calculate a weight corresponding to each of the plurality of unit sections based on the total resistance and the calculated plurality of unit resistances.

[0010] The control unit may be configured to calculate a ratio of each of the plurality of unit resistances to the total resistance and to produce a weight corresponding to each of the plurality of unit sections.

[0011] The control unit may be configured to select any one resistance included in each of the plurality of unit sections as the reference resistance, and calculate the total resistance by weighting the reference resistance of the plurality of unit sections and the weight.

[0012] The above control unit may be configured to compare the calculated total resistance with a preset threshold resistance and diagnose the state of the battery based on the comparison result.

[0013] The control unit may be configured to calculate a total resistance for each of the plurality of batteries and compare the calculated total resistances to determine relative performance between the plurality of batteries.

[0014] The control unit may be configured to calculate the plurality of combined resistances when the plurality of batteries are charged at the same C-rate, and to compare the calculated plurality of combined resistances.

[0015] The control unit may be configured to calculate the sum resistance for each C-rate during the charging process of the battery, and generate a second profile indicating a correspondence between the C-rate and the sum resistance.

[0016] The control unit may be configured to generate a second profile for each of the plurality of batteries, and compare the sum resistances of the plurality of second profiles by C-rate to determine relative performance between the plurality of batteries.

[0017] A battery pack according to another aspect of the present invention may include a battery management device according to one aspect of the present invention.

[0018] A vehicle according to another aspect of the present invention may include a battery management device according to one aspect of the present invention.

[0019] A battery management method according to another aspect of the present invention may include a voltage measuring step of measuring the voltage of a battery being charged while repeating a charger and an idle period; a resistance calculating step of calculating a resistance corresponding to each of a plurality of idle periods; a profile generating step of generating a first profile indicating a correspondence between the SOC and the resistance of the battery; an SOC section dividing step of dividing the SOC section of the first profile into a plurality of unit sections; and a sum resistance calculating step of calculating a sum resistance of the battery based on a weight and a resistance corresponding to each of the plurality of unit sections.

[0020] According to another aspect of the present invention, a battery storage medium may be a non-transitory readable storage medium storing a program for executing a battery management method, the method comprising: a voltage measuring step of measuring the voltage of a battery being charged by repeating a charger and an idle period; a resistance calculating step of calculating a resistance corresponding to each of a plurality of idle periods; a profile generating step of generating a first profile indicating a correspondence between the SOC and the resistance of the battery; an SOC section dividing step of dividing the SOC section of the first profile into a plurality of unit sections; and a sum resistance calculating step of calculating a sum resistance of the battery based on a weight and a resistance corresponding to each of the plurality of unit sections.

[0021] According to one aspect of the present invention, since the resistance index of the battery is determined based on the first profile acquired during the charging process, the state of the battery can be judged in various aspects through an absolute comparison or relative comparison of the determined resistance index.

[0022] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0023] The following drawings attached to this specification serve to further understand the technical idea of ​​the present invention together with the detailed description of the invention described below, and therefore the present invention should not be interpreted as being limited to the matters described in such drawings.

[0024] FIG. 1 is a schematic diagram illustrating a battery management device according to one embodiment of the present invention.

[0025] FIG. 2 is a diagram schematically illustrating a rest period of a battery according to one embodiment of the present invention.

[0026] FIG. 3 and FIG. 4 are schematic drawings illustrating a first profile according to one embodiment of the present invention.

[0027] Figure 5 is a schematic diagram illustrating an embodiment of calculating a sum resistance corresponding to the first profile.

[0028] FIG. 6 is a schematic drawing of a second profile according to one embodiment of the present invention.

[0029] FIG. 7 is a schematic drawing of a battery pack according to another embodiment of the present invention.

[0030] FIG. 8 is a schematic drawing of a vehicle according to another embodiment of the present invention.

[0031] FIG. 9 is a diagram schematically illustrating a battery management method according to another embodiment of the present invention.

[0032] Terms or words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best possible manner.

[0033] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0034] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

[0035] Terms that include ordinal numbers, such as first, second, etc., are used to distinguish one of the various components from the rest, and are not used to limit the components by such terms.

[0036] Throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0037] Additionally, throughout the specification, when we say that a part is "connected" to another part, this includes not only cases where it is "directly connected" but also cases where it is "indirectly connected" with other elements in between.

[0038]

[0039] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0040] FIG. 1 is a schematic diagram illustrating a battery management device (100) according to one embodiment of the present invention.

[0041] Referring to FIG. 1, a battery management device (100) may include a measurement unit (110) and a control unit (120).

[0042] The measuring unit (110) can be configured to measure the voltage of a battery being charged by repeating the charging and resting periods.

[0043] A battery is a physically separate, independent cell with a negative terminal and a positive terminal. For example, a lithium-ion battery or a lithium polymer battery may be considered a battery. Furthermore, the battery may be cylindrical, prismatic, or pouch-shaped. Furthermore, a battery may also refer to a battery bank, battery module, or battery pack, in which multiple cells are connected in series and / or parallel. For convenience of explanation, the term "battery" will be described herein as referring to a single, independent cell.

[0044] Batteries can be recharged through alternating charging and rest periods under certain conditions. The charging period is when the battery is charged at a specified C-rate, while the rest period is when charging is temporarily suspended.

[0045] For example, a battery may be charged for a predetermined charging time (or charging capacity), and charging of the battery may be stopped for a predetermined pause time. The battery charging and pause cycles may be repeated until the battery voltage (or state of charge (SOC)) reaches a preset charge termination voltage (or charge termination SOC).

[0046] The measuring unit (110) can measure the voltage of the battery according to a preset voltage measurement cycle. The voltage measurement cycle can be preset so that the voltage is measured at the start and end points of the rest period.

[0047] FIG. 2 is a diagram schematically illustrating a rest period of a battery according to one embodiment of the present invention.

[0048] In the embodiment of FIG. 2, the battery is charged at a time point before Ts, and the charging current is Ic. The time point before Ts is the battery charger. Thereafter, the battery charging may be stopped from the time point Ts to the time point Td. The time point from Ts to Td is the battery's rest period. The battery is charged at a time point after Td, and the charging current is Ic. The time point after Td is the battery charger.

[0049] The control unit (120) may be configured to produce a resistance corresponding to each of the plurality of rest periods.

[0050] Specifically, the control unit (120) can calculate the resistance of the battery based on the voltage drop during the idle period. Since the application of the charging current is stopped during the idle period, the voltage of the battery may decrease. Afterwards, when charging is resumed, the voltage of the battery may increase again. In other words, the control unit (120) can calculate the resistance value corresponding to the idle period based on the amount of voltage drop during the idle period. Preferably, the control unit (120) can calculate the resistance value of the battery according to Ohm's law.

[0051] For example, in the embodiment of FIG. 2, the voltage of the battery may decrease from Vs[V] to Vd[V] during the rest period. The control unit (120) may calculate the resistance of the battery by calculating the formula “(Vs-Vd)÷Ic”.

[0052] The battery charging process may include one or more pause periods. Accordingly, the control unit (120) may calculate a resistance corresponding to each of the one or more pause periods. For example, if the battery charging process includes n pause periods (where n is a natural number greater than or equal to 1), the control unit (120) may calculate n resistance values.

[0053] The control unit (120) may be configured to generate a first profile (P1) indicating a correspondence between the SOC and resistance of the battery.

[0054] Specifically, the control unit (120) can generate a first profile (P1) indicating a correspondence relationship between SOC and resistance corresponding to each rest period.

[0055] More specifically, the control unit (120) can determine the SOC corresponding to the start voltage of the rest period as the SOC corresponding to the rest period. Here, the control unit (120) can estimate the SOC corresponding to the rest period by referring to a SOC-voltage profile preset to indicate the correspondence between the SOC and the voltage. In addition, the control unit (120) can map the calculated resistance corresponding to the rest period and the estimated SOC.

[0056] For example, in the embodiment of FIG. 2, the control unit (120) can estimate the SOC corresponding to Vs[V] based on the SOC-voltage profile. Then, the control unit (120) can map the estimated SOC and the calculated resistance to each other.

[0057] Figures 3 and 4 are schematic diagrams illustrating a first profile (P1) according to one embodiment of the present invention. Specifically, the first profile (P1) can be expressed as an XY graph in which the X-axis is set to SOC and the Y-axis is set to resistance.

[0058] FIG. 3 illustrates the resistance and the first profile (P1) calculated by the control unit (120). Since the control unit (120) calculates the resistance corresponding to each of the plurality of rest periods, the calculated resistances may be discontinuous. Accordingly, the control unit (120) may generate the first profile (P1), which is a continuous regression curve for the plurality of resistances, using a regression model. That is, in the first profile (P1), the resistance may be expressed as a function of the SOC (resistance = f(SOC)).

[0059] The control unit (120) can be configured to divide the SOC section of the first profile (P1) into a plurality of unit sections.

[0060] For example, it is assumed that the charging start SOC of the battery is SOCi, the charging end SOC is SOCf, and the control unit (120) divides the SOC section into m (m is a natural number greater than or equal to 2) unit sections. Here, the sizes of the unit sections can all be the same. The SOC section of the first profile (P1) is SOCi to SOCf. The control unit (120) divides the SOC section into m unit sections, and the size of each unit section can be calculated as "(SOCf-SOCi)÷m".

[0061] In the embodiment of FIG. 4, the control unit (120) can divide the SOC section of the first profile (P1) into 10 unit sections. The SOC section of the first profile (P1) is divided into the first to tenth unit sections (R1 to R10), and the sizes of the plurality of unit sections (R1 to R10) are all the same.

[0062] The control unit (120) may be configured to calculate the total resistance of the battery based on the weights and reference resistance corresponding to each of the plurality of unit sections.

[0063] Specifically, the control unit (120) may be configured to select any one of the resistances included in each of the plurality of unit sections as the reference resistance. Here, the control unit (120) may be configured to equally apply the conditions for selecting the reference resistance for the unit section to the plurality of unit sections. For example, the control unit (120) may select the resistance corresponding to the start SOC, end SOC, or middle SOC of the unit section as the reference resistance of the corresponding unit section. As another example, the control unit (120) may select the highest resistance, lowest resistance, middle resistance, or average resistance of the unit section as the reference resistance.

[0064] In addition, the control unit (120) may be configured to calculate a combined resistance by weighting the reference resistance and weights of a plurality of unit sections. Here, the weights may be set to correspond to each of the plurality of unit sections.

[0065] Preferably, since the sizes of the plurality of unit sections are all the same, the weights can be set based on the resistance included in each of the plurality of unit sections. And, the sum of the weights for the plurality of unit sections is 1 or 100%. For example, in the embodiment of FIG. 4, the control unit (120) can set weights for each of the first to tenth unit sections (R1 to R10). Here, the total sum of the weights set for the first to tenth unit sections (R1 to R10) can be 1 or 100%.

[0066] In addition, the control unit (120) can calculate the formula of "reference resistance × weight" for each of a plurality of unit sections and add up all the calculated values ​​to calculate the total resistance for the battery. That is, the calculated total resistance is a representative resistance value for the first profile (P1) of the battery, and thus can be used as a resistance index for the first profile (P1) of the battery.

[0067] FIG. 5 is a schematic diagram illustrating an embodiment of calculating a sum resistance corresponding to a first profile (P1).

[0068] In the embodiment of FIG. 5, the unit resistance of the first unit section (R1) is a1 [Ω], the weight is w1, and the reference resistance is r1 [Ω]. The unit resistance of the second unit section (R2) is a2 [Ω], the weight is w2, and the reference resistance is r2 [Ω]. The unit resistance of the third unit section (R3) is a3 [Ω], the weight is w3, and the reference resistance is r3 [Ω]. The unit resistance of the fourth unit section (R4) is a4 [Ω], the weight is w4, and the reference resistance is r4 [Ω]. The unit resistance of the fifth unit section (R5) is a5 [Ω], the weight is w5, and the reference resistance is r5 [Ω]. The unit resistance of the sixth unit section (R6) is a6 [Ω], the weight is w6, and the reference resistance is r6 [Ω]. The unit resistance of the seventh unit section (R7) is a7 [Ω], the weight is w7, and the reference resistance is r7 [Ω]. The unit resistance of the eighth unit section (R8) is a8 [Ω], the weight is w8, and the reference resistance is r8 [Ω]. The unit resistance of the ninth unit section (R9) is a9 [Ω], the weight is w9, and the reference resistance is r9 [Ω]. The unit resistance of the tenth unit section (R10) is a10 [Ω], the weight is w10, and the reference resistance is r10 [Ω]. The control unit (120) can multiply the weights of the first to tenth unit sections (R1 to R10) by the reference resistance, and add up all the multiplied values ​​to calculate the combined resistance.

[0069] A battery management device (100) according to one embodiment of the present invention has a feature that can determine a resistance index representing the battery based on the weight and reference resistance of each of a plurality of unit sections. That is, according to the present invention, since the resistance index of the battery is determined based on the first profile (P1) acquired during the charging process, the state of the battery can be determined from various aspects through absolute or relative comparison of the determined resistance index. In addition, since a single value called the total resistance is calculated according to a specifically set routine, consistency in deriving the resistance index representing the state of the battery can be guaranteed.

[0070]

[0071] Meanwhile, the control unit (120) provided in the battery management device (100) may optionally include a processor, an application-specific integrated circuit (ASIC), another chipset, a logic circuit, a register, a communication modem, a data processing device, etc. known in the art to execute various control logics performed in the present invention. In addition, when the control logic is implemented in software, the control unit (120) may be implemented as a set of program modules. At this time, the program modules may be stored in a memory and executed by the control unit (120). The memory may be located inside or outside the control unit (120) and may be connected to the control unit (120) by various well-known means.

[0072] In addition, the battery management device (100) may further include a storage unit (130). The storage unit (130) may store data or programs required for each component of the battery management device (100) to perform operations and functions, or data generated in the process of performing operations and functions. The storage unit (130) is not particularly limited in type as long as it is a known information storage means known to be capable of recording, erasing, updating, and reading data. As an example, the information storage means may include a RAM (Random Access Memory), a flash memory, a ROM (Read-Only Memory), an EEPROM (Electronically Erasable Programmable Read-Only Memory), a register, etc. In addition, the storage unit (130) may store program codes defining processes executable by the control unit (120).

[0073] For example, the storage unit (130) can store information about the voltage of the battery measured by the measurement unit (110). In addition, the storage unit (130) can store the resistance value for each rest period calculated by the control unit (120) and the first profile (P1) generated by the control unit (120).

[0074]

[0075] Below, an embodiment in which the control unit (120) calculates weights for each unit section is specifically described.

[0076] The control unit (120) can be configured to calculate the total resistance for the SOC section and the unit resistance for each of the plurality of unit sections.

[0077] Specifically, the control unit (120) can calculate the area of ​​the SOC section to calculate the total resistance. Preferably, the control unit (120) can calculate the total resistance by integrating the SOC section with respect to the SOC. That is, the control unit (120) can calculate the total resistance by calculating the total sum of the resistances for the SOC section. For example, in the embodiments of FIGS. 4 and 5, the control unit (120) can calculate the total resistance (A [Ω]) by integrating the first profile (P1) with respect to the SOC.

[0078] The control unit (120) can calculate the area of ​​each of the plurality of unit sections, and calculate the unit resistance of each of the plurality of unit sections. Preferably, the control unit (120) can calculate the unit resistance of each of the plurality of unit sections by integrating each of the plurality of unit sections with respect to the SOC. For example, in the embodiments of FIGS. 4 and 5, the control unit (120) can calculate the unit resistance of the first unit section (R1) as a1 [Ω], the unit resistance of the second unit section (R2) as a2 [Ω], and the unit resistance of the third unit section (R3) as a3 [Ω]. The control unit (120) can calculate the unit resistance of the fourth unit section (R4) as a4 [Ω], the unit resistance of the fifth unit section (R5) as a5 [Ω], and the unit resistance of the sixth unit section (R6) as a6 [Ω]. The control unit (120) can calculate the unit resistance of the seventh unit section (R7) as a7 [Ω], the unit resistance of the eighth unit section (R8) as a8 [Ω], the unit resistance of the ninth unit section (R9) as a9 [Ω], and the unit resistance of the tenth unit section (R10) as a10 [Ω].

[0079] The control unit (120) can be configured to calculate a weight corresponding to each of a plurality of unit sections based on the total resistance and the calculated plurality of unit resistances.

[0080] Specifically, the control unit (120) may be configured to calculate the ratio of each of the plurality of unit resistances to the total resistance and to produce a weight corresponding to each of the plurality of unit sections. For example, if the total resistance is A and the unit resistance of the nth unit section is an, the control unit (120) may calculate the formula “an÷A” to produce a weight (wn) for the nth unit section.

[0081] For example, in the embodiments of FIGS. 4 and 5, the control unit (120) can calculate the ratio of the unit resistances (a1[Ω] to a10[Ω]) of each of the first to tenth unit sections (R1 to R10) to the total resistance (A[Ω]), thereby calculating weights of w1 to w10. That is, the weight of the first unit section (R1) is w1, the weight of the second unit section (R2) is w2, and the weight of the third unit section (R3) is w3. The weight of the fourth unit section (R4) is w4, the weight of the fifth unit section (R5) is w5, and the weight of the sixth unit section (R6) is w6. The weight of the seventh unit section (R7) is w7, the weight of the eighth unit section (R8) is w8, the weight of the ninth unit section (R9) is w9, and the weight of the tenth unit section (R10) is w10.

[0082] The control unit (120) can multiply the weight and the reference resistance for each unit section and add all the multiplied values ​​to calculate the total resistance corresponding to the first profile (P1).

[0083] Additionally, the control unit (120) can be configured to compare the calculated total resistance with a preset threshold resistance.

[0084] Specifically, the total resistance is a resistance indicator indicating the battery's condition and is calculated as a single value. Accordingly, the control unit (120) can compare the total resistance with a preset threshold resistance. Here, the threshold resistance is a reference value that can distinguish the battery's condition as normal or abnormal based on the battery's resistance, and can be preset experimentally or theoretically, taking into account the battery's type, specifications, and deterioration level.

[0085] The control unit (120) may be configured to diagnose the condition of the battery based on the comparison result.

[0086] For example, the control unit (120) can diagnose the battery's condition as abnormal if the total resistance exceeds the threshold resistance. As another example, the control unit (120) can diagnose the battery's condition as normal if the total resistance is below the threshold resistance.

[0087]

[0088] Meanwhile, the control unit (120) can calculate the combined resistance for multiple batteries. In addition, the control unit can be configured to compare the calculated combined resistance to determine the relative performance between the multiple batteries.

[0089] Preferably, the control unit (120) can calculate the sum resistance of multiple batteries and compare the sum resistance of batteries charged at the same C-rate. Specifically, since the sum resistance of the batteries also changes when the C-rate changes, comparing the sum resistance of batteries charged at different C-rates may not accurately determine the relative performance of the multiple batteries. Therefore, the control unit (120) can compare the sum resistance of batteries charged at the same C-rate to determine the relative performance of the multiple batteries.

[0090] Typically, as a battery degrades, its internal resistance increases, which in turn increases the total resistance per C-rate. Furthermore, since the degree of degeneration is inversely proportional to performance, battery performance deteriorates as the battery degrades. Therefore, the control unit (120) can determine the relative performance of multiple batteries based on the comparison of the total resistances.

[0091] For example, the control unit (120) may determine that the battery with the largest combined resistance has the worst performance, and that the battery with the smallest combined resistance has the best performance.

[0092]

[0093] The control unit (120) can be configured to calculate the total resistance for each C-rate during the charging process of the battery.

[0094] Preferably, in order to calculate the sum resistance for each C-rate of the battery, the C-rate may not change during the charging process of the battery. The control unit (120) may calculate the sum resistance so as to correspond to the first profile (P1) obtained during each charging process.

[0095] For example, when the battery is charged at 0.33C, 0.5C, 0.7C, 1C, 1.5C, 2C, and 2.5C, the control unit (120) can calculate the sum resistance corresponding to each C-rate. That is, the control unit (120) can calculate seven sum resistances.

[0096] The control unit (120) may be configured to generate a second profile representing a correspondence between the C-rate and the summation resistance. Specifically, the second profile may be expressed as an XY graph in which the X-axis is set to the C-rate and the Y-axis is set to the summation resistance.

[0097] The control unit (120) may be configured to generate a second profile for each of the plurality of batteries.

[0098] FIG. 6 is a schematic diagram illustrating a second profile according to one embodiment of the present invention. Specifically, FIG. 6 is a diagram illustrating a second profile (P21) for a first battery and a second profile (P22) for a second battery.

[0099] For example, in the embodiment of FIG. 6, the control unit (120) can calculate the sum resistance of the first battery and the second battery at 0.33C, 0.5C, 0.7C, 1C, 1.5C, 2C, and 2.5C, and generate a second profile (P21) for the first battery and a second profile (P22) for the second battery based on the calculated sum resistances. Preferably, the control unit can generate the second profile, which is a continuous regression curve for a plurality of sum resistances, using a regression model.

[0100] The control unit (120) may be configured to compare the sum resistances of the C-rates of the plurality of second profiles to determine the relative performance between the plurality of batteries.

[0101] Specifically, the control unit (120) can determine the relative performance of multiple batteries by C-rate by comparing the total resistance of multiple batteries by C-rate. Here, the relative performance is an index for relatively evaluating performance such as charge / discharge efficiency or output efficiency. That is, since the loss due to resistance increases as the total resistance increases, a battery with better relative performance can be said to have better charge / discharge efficiency (or output efficiency, etc.) than the remaining batteries.

[0102] For example, for the first C-rate, if the total resistance of battery A is greater than the total resistance of battery B, the control unit (120) can determine that the performance of battery B is superior to that of battery A at the first C-rate. In other words, the control unit (120) can determine that battery B can exhibit better performance than battery A at the first C-rate.

[0103] For example, in the embodiment of FIG. 6, the combined resistance of the first battery is greater than the combined resistance of the second battery for all C-rates. Therefore, the control unit (120) can determine that the performance of the second battery is superior to that of the first battery for all C-rates.

[0104] A battery management device (100) according to one embodiment of the present invention can determine the relative performance of multiple batteries by comparing the total resistance for each C-rate. That is, according to the present invention, the performance of batteries can be compared and determined for each C-rate.

[0105] For example, in an environment where battery replacement is possible, such as a battery swap station (BSS), the battery most suitable for the user's usage environment (e.g., commonly used C-rate, recommended C-rate, or maximum allowed C-rate, etc.) can be selected based on the relative performance judgment results. In other words, according to the present invention, battery usage efficiency can be significantly improved.

[0106]

[0107] The battery management device (100) according to the present invention can be applied to a BMS (Battery Management System). That is, the BMS according to the present invention can include the battery management device (100) described above. In this configuration, at least some of the components of the battery management device (100) can be implemented by supplementing or adding to the functions of the components included in a conventional BMS. For example, the measurement unit (110), control unit (120), and storage unit (130) of the battery management device (100) can be implemented as components of the BMS.

[0108] Additionally, the battery management device (100) according to the present invention may be provided in a battery pack. That is, the battery pack according to the present invention may include the battery management device (100) described above and one or more battery cells. Additionally, the battery pack may further include electrical components (relays, fuses, etc.) and a case.

[0109] FIG. 7 is a schematic drawing of a battery pack according to another embodiment of the present invention.

[0110] The positive terminal of the battery (11) can be connected to the positive terminal (P+) of the battery pack (10), and the negative terminal of the battery (11) can be connected to the negative terminal (P-) of the battery pack (10).

[0111] The measuring unit (110) may be connected to a first sensing line (SL1), a second sensing line (SL2), and a third sensing line (SL3). Specifically, the measuring unit (110) may be connected to a positive terminal of the battery (11) through the first sensing line (SL1), and may be connected to a negative terminal of the battery (11) through the second sensing line (SL2). The measuring unit (110) may measure the voltage of the battery (11) based on the voltage measured at each of the first sensing line (SL1) and the second sensing line (SL2).

[0112] And, the measuring unit (110) can be connected to the current measuring unit (A) through the third sensing line (SL3). For example, the current measuring unit (A) can be an ammeter or a shunt resistor capable of measuring the charging current and discharging current of the battery (11). The measuring unit (110) can measure the charging current of the battery (11) through the third sensing line (SL3) to calculate the charging amount. In addition, the measuring unit (110) can measure the discharging current of the battery (11) through the third sensing line (SL3) to calculate the discharging amount.

[0113] An external device can be connected to the positive terminal (P+) and negative terminal (P-) of the battery pack (10). The positive terminal of the battery (11), the positive terminal (P+) of the battery pack (10), the external device, the negative terminal (P-) of the battery pack (10), and the negative terminal of the battery (11) can be electrically connected.

[0114] For example, a charging device (20) may be connected to the positive terminal (P+) and negative terminal (P-) of the battery pack (10). Here, the charging device (20) is a device for charging the battery (11).

[0115] The control unit (120) can be connected to the charging device (20) via a communication line (CL) to enable wired and / or wireless communication. For example, the control unit (120) can perform power-line communication (PLC) with the charging device (20).

[0116] For example, the control unit (120) can command the charging device (20) to charge and pause so that the charging and pause cycles are repeated under preset conditions.

[0117] As another example, a charging protocol that repeats charging and resting periods may be preset in the charging device (20). The charging device (20) charges the battery according to the charging protocol, and the control unit (120) may calculate the total resistance of the battery based on the measurement results.

[0118]

[0119] FIG. 8 is a schematic drawing of a vehicle (800) according to another embodiment of the present invention.

[0120] Referring to FIG. 8, a battery pack according to an embodiment of the present invention may be included in a vehicle (800), such as an electric vehicle (EV) or a hybrid vehicle (HV). Furthermore, the battery pack (810) may drive the vehicle (800) by supplying power to a motor through an inverter provided in the vehicle (800). Here, the battery pack (810) may include a battery management device (100). That is, the vehicle (800) may include a battery management device (100). In this case, the battery management device (100) may be an onboard device included in the vehicle (800).

[0121]

[0122] FIG. 9 is a diagram schematically illustrating a battery management method according to another embodiment of the present invention.

[0123] Referring to FIG. 9, the battery management method may include a voltage measurement step (S100), a resistance calculation step (S200), a profile generation step (S300), an SOC section division step (S400), and a total resistance calculation step (S500).

[0124] Preferably, each step of the battery management method can be performed by a battery management device (100). In the following, for convenience of explanation, any content that overlaps with the previously described content will be omitted or briefly described.

[0125] The voltage measurement step (S100) is a step of measuring the voltage of a battery being charged by repeating the charging and resting periods, and can be performed by the measuring unit (110).

[0126] For example, a battery may be charged for a predetermined charging time (or charging capacity), and charging of the battery may be stopped for a predetermined idle time. The measuring unit (110) may measure the voltage of the battery according to a preset voltage measurement cycle. Preferably, the voltage measurement cycle may be preset so that the voltage is measured at the start and end of the idle period.

[0127] The resistance calculation step (S200) is a step of calculating the resistance corresponding to each of the plurality of rest periods, and can be performed by the control unit (120).

[0128] Specifically, the control unit (120) can calculate the resistance of the battery based on the voltage drop during the idle period. For example, in the embodiment of FIG. 2, the voltage of the battery can decrease from Vs [V] to Vd [V] during the idle period. The control unit (120) can calculate the resistance of the battery by calculating the formula “(Vs-Vd)÷Ic.”

[0129] The profile generation step (S300) is a step for generating a first profile (P1) indicating a correspondence relationship between the SOC and resistance of the battery, and can be performed by the control unit (120).

[0130] Specifically, the control unit (120) can generate a first profile (P1) indicating a correspondence between the SOC and resistance corresponding to each rest period. For example, FIGS. 3 and 4 are schematic diagrams illustrating a first profile (P1) according to one embodiment of the present invention.

[0131] The SOC section division step (S400) is a step of dividing the SOC section of the first profile (P1) into multiple unit sections, and can be performed by the control unit (120).

[0132] Specifically, the control unit (120) can divide the SOC section of the first profile (P1) into two or more unit sections.

[0133] The sum resistance calculation step (S500) is a step of calculating the sum resistance of the battery based on the weights and resistances corresponding to each of a plurality of unit sections, and can be performed by the control unit (120).

[0134] Specifically, the control unit (120) may be configured to select any one resistance included in each of the plurality of unit sections as a reference resistance. In addition, the control unit (120) may be configured to calculate the total resistance for the SOC section and the unit resistance for each of the plurality of unit sections. In addition, the control unit (120) may be configured to calculate a ratio of each of the plurality of unit resistances to the total resistance and to calculate a weight corresponding to each of the plurality of unit sections. Finally, the control unit (120) may be configured to calculate a sum resistance by weighted summing the reference resistances and the weights of the plurality of unit sections.

[0135]

[0136] The embodiments of the present invention described above are not implemented only through devices and methods, but may also be implemented through a program that realizes a function corresponding to the configuration of the embodiments of the present invention or a recording medium on which the program is recorded, and such implementation can be easily implemented by an expert in the technical field to which the present invention belongs based on the description of the embodiments described above.

[0137] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0138] In addition, the present invention described above is not limited to the above-described embodiments and the attached drawings, and all or part of each embodiment may be selectively combined and configured so that various modifications can be made, as those skilled in the art can make various substitutions, modifications, and changes within the scope of the technical idea of ​​the present invention.

[0139] (Explanation of symbols)

[0140] 10: Battery pack

[0141] 11: Battery

[0142] 20: Charging device

[0143] 100: Battery management device

[0144] 110: Measurement section

[0145] 120: Control unit

[0146] 130: Storage

[0147] 800: Car

[0148] 810: Battery Pack

Claims

1. A measuring unit configured to measure the voltage of a battery being charged by repeating the charging and resting periods; and A battery management device comprising a control unit configured to calculate resistance corresponding to each of a plurality of rest periods, generate a first profile indicating a correspondence between the SOC and the resistance of the battery, divide the SOC section of the first profile into a plurality of unit sections, and calculate a total resistance of the battery based on a weight and a reference resistance corresponding to each of the plurality of unit sections.

2. In paragraph 1, The above control unit, A battery management device characterized in that it is configured to calculate the total resistance for the SOC section and the unit resistance for each of the plurality of unit sections, and to calculate a weight corresponding to each of the plurality of unit sections based on the total resistance and the calculated plurality of unit resistances.

3. In paragraph 2, The above control unit, A battery management device characterized in that it is configured to calculate a ratio of each of the plurality of unit resistances to the total resistance and to produce a weight corresponding to each of the plurality of unit sections.

4. In paragraph 2, The above control unit, A battery management device characterized in that it is configured to select any one resistance included in each of the plurality of unit sections as the reference resistance, and calculate the sum resistance by weighting the reference resistance of the plurality of unit sections and the weight.

5. In paragraph 1, The above control unit, A battery management device characterized in that it is configured to compare the calculated total resistance with a preset threshold resistance and diagnose the condition of the battery based on the comparison result.

6. In paragraph 1, The above control unit, A battery management device characterized in that it is configured to calculate a sum resistance for each of a plurality of batteries and compare the calculated sum resistances to determine relative performance between the plurality of batteries.

7. In paragraph 6, The above control unit, A battery management device configured to calculate the plurality of total resistances when the plurality of batteries are charged at the same C-rate, and to compare the calculated plurality of total resistances.

8. In paragraph 1, The above control unit, A battery management device characterized in that it is configured to calculate the sum resistance for each C-rate during the charging process of the battery and generate a second profile indicating a correspondence between the C-rate and the sum resistance.

9. In paragraph 8, The above control unit, A battery management device characterized in that it generates a second profile for each of a plurality of batteries and is configured to compare the sum resistances of the plurality of second profiles by C-rate to determine relative performance among the plurality of batteries.

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

11. A vehicle including a battery management device according to any one of claims 1 to 9.

12. Voltage measurement step to measure the voltage of the battery being charged by repeating the charging and resting periods; A resistance calculation step for calculating the resistance corresponding to each of the plurality of rest periods; A profile generation step for generating a first profile representing the correspondence between the SOC and resistance of the battery; A SOC section division step for dividing the SOC section of the first profile into multiple unit sections; and A battery management method, characterized in that it includes a sum resistance calculation step for calculating the sum resistance of the battery based on the weight and resistance corresponding to each of the plurality of unit sections.

13. Voltage measurement step for measuring the voltage of the battery being charged by repeating the charging and resting periods; A resistance calculation step for calculating the resistance corresponding to each of the plurality of rest periods; A profile generation step for generating a first profile representing the correspondence between the SOC and resistance of the battery; A SOC section division step for dividing the SOC section of the first profile into multiple unit sections; and A non-transitory readable storage medium storing a program for executing a battery management method, the method including a sum resistance calculation step for calculating the sum resistance of the battery based on weights and resistances corresponding to each of the plurality of unit sections.

Images