Battery management system, battery pack, electric vehicle, and method for predicting battery charging time

Abstract

A battery management system, a battery pack, an electric vehicle, and a method for predicting a battery charging time are provided. The battery management system includes a memory for storing a first charging reference map in which a total of M×N charging rates for first to Mth SOC intervals and first to Nth temperature intervals are recorded, a sensing unit for detecting a voltage, a current, and a temperature of a battery, and a control unit for determining an estimated SOC value of the battery. The control unit determines an mth charging rate associated with an mth SOC interval to which the estimated SOC value belongs and a temperature interval to which the detected temperature value belongs in the first charging reference map. The control unit determines a predicted charging time value in the mth SOC interval based on the mth charging rate and an SOC difference between the estimated SOC value and an end point of the mth SOC interval.

Description

[Technical field]

[0001] The present invention relates to a technique for estimating remaining charging time of a battery.

[0002] This application claims priority to Korean Patent Application No. 10-2022-0116579 filed on September 15, 2022 and Korean Patent Application No. 10-2023-0054311 filed on April 25, 2023, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings. [Background technology]

[0003] Recently, as the demand for portable electronic products such as notebook PCs, video cameras, and mobile phones has increased sharply and the development of electric vehicles, energy storage batteries, robots, satellites, etc. has progressed in earnest, research into high-performance batteries that can be repeatedly charged and discharged is progressing actively.

[0004] Currently, commercial batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium batteries. Of these, lithium batteries are in the spotlight due to their advantages over nickel-based batteries, such as almost no memory effect, freedom to charge and discharge, a very low self-discharge rate, and high energy density.

[0005] When charging a battery, if the charging rate (C-rate) of the charging current is small, it takes a very long time to fully charge the battery. On the other hand, if the charging rate of the charging current is too high, it has the side effect of causing the battery to deteriorate quickly. Therefore, it is necessary to gradually adjust the charging rate of the charging current according to the state of the battery during constant current charging. For your reference, the charging rate (sometimes called "C-rate") is the value obtained by dividing the charging current by the maximum capacity of the battery, and the unit used is "C."

[0006] In order to adjust the charging rate in stages during constant current charging, a charging rate map having a so-called "multi-stage constant-current charging protocol" is mainly used. A separate charging rate map may be created for each of a plurality of temperature intervals, and a particular charging rate map is a table or function in which the relationship between a plurality of charging rates associated with a particular temperature interval and a plurality of switching conditions is recorded. When the state of the battery satisfies a particular switching condition (e.g., SOC reaches 60%) during charging using any one of the plurality of charging rates recorded in the particular charging rate map, the next sequential charging rate may be supplied to the battery as a charging current.

[0007] Incidentally, while the battery is being charged, it is necessary to notify the user of how much time remains until the battery's SOC reaches a target SOC (eg, a fully charged state).

[0008] Conventionally, when gradually changing the charging rate during charging using a multi-stage constant current charging protocol, there was no method for reflecting changes in battery temperature, and the remaining charging time was predicted under the assumption that the battery temperature at the start of charging would continue to be maintained.

[0009] However, it is common knowledge that the battery temperature generally increases during charging, and therefore, there is a problem that the remaining charging time predicted by the above-mentioned conventional method shows a large difference from the actual charging time. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in consideration of the above problems, and aims to provide a battery management system that can improve the accuracy of predicting the remaining charging time until the SOC of the battery reaches a target SOC by repeating the process of predicting a battery temperature change in each stage (SOC range) during charging using a multi-stage constant current charging protocol, estimating a charging rate to be used in the next stage, and predicting a charging time prediction value in each stage based on the estimated charging rate, the battery management system, a battery pack including the battery management system, an electric vehicle including the battery pack, and a method for predicting a battery charging time that can be implemented in the battery management system.

[0011] Other objects and advantages of the present invention can be understood from the following description and will become more clearly understood from the embodiments of the present invention. Also, the objects and advantages of the present invention can be realized by the means and combinations thereof as claimed in the claims. [Means for solving the problem]

[0012] According to an aspect of the present invention, a battery management system includes a memory configured to store a first charging reference map in which a total of M×N charging rates for first to Mth SOC intervals (M is a natural number equal to or greater than 2) and first to Nth temperature intervals (N is a natural number equal to or greater than 2) associated with a multi-stage constant current charging protocol are recorded; a sensing unit configured to detect a voltage, a current, and a temperature of a battery; and a control unit configured to determine an estimated SOC value of the battery based on a detected voltage value, a detected current value, and a detected temperature value at a predetermined time interval from a start point of a charging process for the battery. The control unit may be configured to determine an mth charging rate associated with an mth SOC interval (m is a natural number equal to or less than M) to which the estimated SOC value belongs and a temperature interval to which the detected temperature value belongs in the first charging reference map. The control unit may be configured to determine a predicted charging time value in the mth SOC interval based on the mth charging rate and an SOC difference between the estimated SOC value and an end point of the mth SOC interval. The controller may further be configured to determine a temperature prediction value at an end point of the mth SOC interval when m is less than M. The temperature prediction value at the end point of the mth SOC interval indicates the temperature of the battery at a start point of an m+1th SOC interval.

[0013] The control unit may be configured to determine a predicted amount of temperature change from the estimated SOC value to an end point of the m SOC interval based on the m charging rate and a predicted charging time value in the m SOC interval using a predetermined thermal model. The control unit may be configured to determine a predicted temperature value at the end point of the m SOC interval by adding the predicted amount of temperature change from the estimated SOC value to the end point of the m SOC interval to the detected temperature value.

[0014] The memory may be further configured to store a second charging reference map in which a total of M×N internal resistance values ​​for the first to Mth SOC intervals and the first to Nth temperature intervals are recorded.

[0015] The control unit may be configured to determine, from the second charging reference map, an mth internal resistance value associated with the mth SOC interval and the temperature interval to which the detected temperature value belongs. The control unit may also be configured to determine, using a predefined thermal model, a predicted amount of temperature change from the estimated SOC value to an end point of the mth SOC interval, based on the mth charging rate, a predicted charging time value in the mth SOC interval, and the mth internal resistance value. The control unit may be configured to determine a predicted temperature value at the end point of the mth SOC interval by adding the predicted amount of temperature change from the estimated SOC value to the end point of the mth SOC interval to the detected temperature value.

[0016] The control unit may be configured to adjust the m SOC range by comparing a predicted temperature change amount from the estimated SOC value to an end point of the m SOC range with an actual temperature change amount when the charging process for the m SOC range is completed.

[0017] The control unit may be configured to determine a k-th charging rate associated with a temperature range to which the k-th SOC range and the temperature predicted value at the end point of the k-1-th SOC range belong in the first charging reference map when determination of the predicted charging time value in the k-1-th SOC range and the predicted temperature value at the end point of the k-1-th SOC range is completed, where k is a natural number greater than or equal to m+1 and less than or equal to M. The control unit may be configured to determine the predicted charging time value in the k-th SOC range and the predicted temperature value at the end point of the k-1-th SOC range based on the k-th charging rate and a size of the k-th SOC range.

[0018] When the determination of the predicted charging time value in the Mth SOC section is completed, the control unit may be configured to sum up the predicted charging time values ​​determined for the mth to Mth SOC sections to determine a total remaining time until the charging process using the multi-stage constant current charging protocol is completed.

[0019] The control unit may be configured to determine a predicted amount of temperature change in the k-th SOC interval based on the kth charge rate and the predicted amount of charging time in the k-th SOC interval by using a predetermined thermal model when the determination of the predicted charging time in the k-1st SOC interval and the predicted temperature at the end point of the k-1st SOC interval is completed. The control unit may be configured to determine the predicted temperature at the end point of the k-1st SOC interval by adding the predicted amount of temperature change in the k-th SOC interval to the predicted temperature at the end point of the k-1st SOC interval.

[0020] The memory may be further configured to store a second charging reference map in which a total of M×N internal resistance values ​​for the first to Mth SOC intervals and the first to Nth temperature intervals are recorded. The control unit may be configured to determine a kth internal resistance value associated with a temperature interval to which the kth SOC interval and the temperature predicted value at the end point of the k-1st SOC interval belong from the second charging reference map. The control unit may be configured to determine a predicted amount of temperature change in the kth SOC interval based on the kth charging rate, the kth charging time predicted value, and the kth internal resistance value. The control unit may be configured to determine a predicted temperature value at the end point of the kth SOC interval by adding the predicted amount of temperature change in the kth SOC interval to a predicted temperature value at the end point of the kth SOC interval and the k-1st SOC interval.

[0021] The control unit may be configured to adjust the kth SOC range by comparing a predicted temperature change amount in the kth SOC range with an actual temperature change amount when a charging process for the kth SOC range is completed.

[0022] A battery pack according to another aspect of the present invention includes the battery management system.

[0023] According to yet another aspect of the present invention, an electric vehicle includes the battery pack described above.

[0024] According to another aspect of the present invention, a method for predicting a battery charging time is provided to be performed at a predetermined time interval from a start point of a charging process for a battery. The method for predicting a battery charging time includes the steps of: determining an estimated SOC value of the battery based on a voltage detection value, a current detection value, and a temperature detection value of the battery; determining an m-th SOC interval (m is a natural number equal to or less than M) to which the estimated SOC value belongs and an m-th charging rate associated with a temperature interval to which the detected temperature value belongs from a first charging reference map in which a total of M×N charging rates for 1st to Mth SOC intervals and 1st to Nth temperature intervals associated with a multi-stage constant current charging protocol are recorded; and determining a predicted charging time value in the m-th SOC interval based on the m-th charging rate and an SOC difference between the estimated SOC value and an end point of the m-th SOC interval. The method for predicting a battery charging time further includes the step of determining a predicted temperature value at an end point of the m-th SOC interval if m is less than M. The temperature prediction value at the end of the mth SOC interval indicates the temperature of the battery at the start of the m+1th SOC interval.

[0025] The step of determining the mth predicted charging time value in the mth SOC interval may include a step of determining a predicted amount of temperature change from the estimated SOC value to an end point of the mth SOC interval based on the mth charging rate and the predicted charging time value in the mth SOC interval using a predetermined thermal model, and a step of adding the predicted amount of temperature change from the estimated SOC value to the end point of the mth SOC interval to the detected temperature value to determine a predicted temperature value at the end point of the mth SOC interval.

[0026] The method for predicting a battery charging time may further include, when determination of the predicted charging time value in the k-1th SOC interval and the predicted temperature value at the end point of the k-1th SOC interval has been completed, determining a kth charging rate in the first charging reference map associated with a temperature interval to which the kth SOC interval and the predicted temperature value at the end point of the k-1st SOC interval belong, where k is a natural number greater than or equal to m+1 and less than or equal to M, and determining a predicted charging time value in the kth SOC interval and a predicted temperature value at the end point of the kth SOC interval based on the kth charging rate and a size of the kth SOC interval.

[0027] The method for predicting a battery charging time may further include, when determination of the charging time predicted value in the Mth SOC section is completed, determining a total remaining time until the charging process using the multi-stage constant current charging protocol is completed by summing the charging time predicted values ​​determined for the mth to Mth SOC sections. Effect of the Invention

[0028] According to at least one embodiment of the present invention, during charging using a multi-stage constant current charging protocol, the temperature change of the battery at each stage (SOC range) is predicted to estimate the charging rate to be used in the next stage, and the process of predicting the predicted charging time at each stage according to the estimated charging rate is repeated, thereby improving the accuracy of predicting the remaining charging time until the SOC of the battery reaches the target SOC.

[0029] In addition, according to at least one embodiment of the present invention, the accuracy of predicting the remaining charging time can be further improved by predicting the temperature change of the battery at each stage by further utilizing not only the battery temperature but also the outside air temperature.

[0030] In addition, according to at least one embodiment of the present invention, the end point of each stage is adjusted according to the difference between the predicted temperature change amount and the actual temperature change amount for the corresponding stage, thereby improving the prediction accuracy of the remaining charging time in a charging process that is subsequently resumed.

[0031] The effects of the present invention are not limited to the effects described above, and other effects of the present invention not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0032] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief description of the drawings]

[0033] [Figure 1] 1 is a diagram showing the configuration of an electric vehicle according to the present invention;

[0034] [Diagram 2] FIG. 2 is a diagram for explaining a first charging reference map used in a charging process using a multi-stage constant current charging protocol.

[0035] [Diagram 3] 2 is a schematic diagram for explaining an example of a process for estimating a total remaining time performed by the battery management system shown in FIG. 1.

[0036] [Figure 4] FIG. 13 is a diagram for explaining a second charging reference map used in a charging process using a multi-stage constant current charging protocol.

[0037] [Diagram 5] 1. FIG. 4 is a schematic diagram for explaining another example of the estimation process of the total remaining time performed by the battery management system shown in FIG.

[0038] [Figure 6] 2 is a flowchart showing a method for predicting a battery charging time according to a first embodiment of the present invention.

[0039] [Figure 7] 5 is a flowchart showing a method for predicting a battery charging time according to a second embodiment of the present invention.

[0040] [Figure 8] 10 is a flowchart showing a method for predicting a battery charging time according to a third embodiment of the present invention.

[0041] [Figure 9] 10 is a flowchart showing a method for predicting a battery charging time according to a fourth embodiment of the present invention.

[0042] [Figure 10] 13 is a flowchart showing a method for predicting a battery charging time according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as having meanings and concepts according to the technical ideas of the present invention, in accordance with the principle that the inventor himself can appropriately define the concepts of terms in order to best describe the invention.

[0044] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can be substituted for them at the time of this application.

[0045] Terms including ordinal numbers such as "first", "second", etc. are used for the purpose of distinguishing one of various components from the rest, and are not intended to limit the components.

[0046] In addition, throughout the specification, when a certain part "includes" a certain component, this does not mean excluding other components, but means that other components may be further included, unless otherwise specified. Furthermore, terms such as "~part (unit)" in the specification indicate a unit that processes at least one function or operation, which may be embodied by hardware, software, or a combination of hardware and software.

[0047] Furthermore, throughout this specification, when a part is said to be "connected" to another part, this includes not only when it is "directly connected" to another part, but also when it is "indirectly connected" through another element in between.

[0048] FIG. 1 is a diagram showing the configuration of an electric vehicle according to the present invention.

[0049] 1, an electric vehicle 1 includes a vehicle controller 2, a battery pack 10, a relay 20, an inverter 30, and an electric motor 40. Charging and discharging terminals P+, P- of the battery pack 10 may be electrically coupled to a charger 3 via a charging cable or the like. The charger 3 may be included in the electric vehicle 1 or may be provided in a charging station.

[0050] The vehicle controller 2 (e.g., ECU: Electronic Control Unit) is configured to transmit a key-on signal to the battery management system 100 in response to a start button (not shown) provided on the electric vehicle 1 being switched to an on position by a user. The vehicle controller 2 is configured to transmit a key-off signal to the battery management system 100 in response to a start button being switched to an off position by a user. The charger 3 may communicate with the vehicle controller 2 to supply constant current or constant voltage charging power via the charging / discharging terminals P+, P- of the battery pack 10.

[0051] The battery pack 10 includes a battery 11 and a battery management system 100 .

[0052] The battery 11 includes a cell group 12 and a case 13. The case 13 defines the overall outer shape of the battery 11 and provides an internal space in which the cell group 12 is disposed. The case 13 is fixed to a battery room provided in the electric vehicle 1 by bolts or the like.

[0053] The cell group 12 is disposed (housed) in an internal space provided by the case 13 and includes at least one battery cell BC. The type of the battery cell BC is not particularly limited as long as it can be repeatedly charged and discharged, such as a lithium ion cell.

[0054] When the cell group 12 includes a plurality of battery cells, the plurality of battery cells may be connected in series, in parallel, or in a mixed series-parallel configuration.

[0055] The relay 20 is electrically connected in series to the battery 11 through a power path connecting the battery 11 and the inverter 30. In FIG. 1, the relay 20 is shown connected between the positive terminal of the battery 11 and the charge / discharge terminal P+. The relay 20 is controlled to be turned on and off in response to a switching signal from the battery management system 100. The relay 20 may be a mechanical contactor that is turned on and off by the magnetic force of a coil, or may be a semiconductor switch such as a metal oxide semiconductor field effect transistor (MOSFET).

[0056] An inverter 30 is provided to convert direct current from the cell groups 12 to alternating current in response to commands from the battery management system 100 or the vehicle controller 2 .

[0057] The electric motor 40 is driven using AC power from the inverter 30. As the electric motor 40, for example, a three-phase AC motor 40 may be used.

[0058] The battery management system 100 includes a voltage sensor 111, a current sensor 113, a battery temperature sensor 115, and a control unit 130. The battery management system 100 may further include an outside air temperature sensor 117. The battery management system 100 may further include a communication circuit 150.

[0059] The voltage sensor 111 is connected in parallel to the battery 11 and configured to detect a battery voltage, which is the voltage across the battery 11, and generate a voltage signal indicative of the detected battery voltage.

[0060] The current sensor 113 is connected in series to the battery 11 through a current path between the battery 11 and the inverter 30. The current sensor 113 is configured to detect a battery current, which is a current flowing through the battery 11, and generate a current signal indicative of the detected battery current. The current sensor 113 may be embodied by one or a combination of two or more known current detection elements, such as a shunt resistor, a Hall element, etc.

[0061] The battery temperature sensor 115 is configured to detect a battery temperature and generate a temperature signal indicative of the detected battery temperature. The battery temperature sensor 115 may be disposed in the case 13 to detect a temperature close to an actual temperature of the battery 11. For example, the battery temperature sensor 115 may be attached to a surface of at least one battery cell BC included in the cell group 12 and detect the surface temperature of the battery cell BC as the battery temperature.

[0062] The voltage sensor 111, the current sensor 113 and the battery temperature sensor 115 may be referred to as a "sensing unit."

[0063] The outside air temperature sensor 117 is configured to detect an outside air temperature (ambient temperature), which is a temperature at a predetermined position separated from the battery 11, and generate a temperature signal indicating the detected outside air temperature. The outside air temperature sensor 117 may be disposed at a predetermined position outside the case 13 where heat exchange between the battery 11 and the outside air takes place.

[0064] The battery temperature sensor 115 and the outside air temperature sensor 117 may each be implemented by one or a combination of two or more known temperature detection elements such as a thermocouple, a thermistor, a bimetal, and the like.

[0065] The communication circuit 150 is configured to support wired or wireless communication between the control unit 130 and the vehicle controller 2. The wired communication may be, for example, a controller area network (CAN) communication, and the wireless communication may be, for example, ZigBee (registered trademark) or Bluetooth (registered trademark) communication. Of course, the type of communication protocol is not particularly limited as long as it supports wired or wireless communication between the control unit 130 and the vehicle controller 2. The communication circuit 150 may include an output device (for example, a display, a speaker) that provides information received from the control unit 130 and / or the vehicle controller 2 in a form that can be recognized by a user.

[0066] The control unit 130 is operatively coupled to the relay 20, the voltage sensor 111, the current sensor 113, the battery temperature sensor 115, the outside air temperature sensor 117, and the communication circuit 150. The fact that two components are operatively coupled means that the two components are directly or indirectly connected to each other so that signals can be transmitted and received unidirectionally or bidirectionally.

[0067] The control unit 130 may collect a voltage signal from the voltage sensor 111, a current signal from the current sensor 113, a temperature signal from the battery temperature sensor 115 (which may be referred to as a "battery temperature signal"), and / or a temperature signal from the outside air temperature sensor 117 (which may be referred to as an "outside air temperature signal"). The control unit 130 may convert and record each of the analog signals collected from the sensors 111, 113, 115, and 117 into digital values ​​using an ADC (Analog to Digital Converter) provided inside.

[0068] The control unit 130 may be referred to as a "control circuit" or a "battery controller", and may be implemented in hardware using at least one of an ASIC (application specific integrated circuit), a DSP (digital signal processor), a DSPD (digital signal processing device), a PLD (programmable logic device), an FPGA (field programmable gate array), a microprocessor, or other electrical unit for performing a function.

[0069] The memory 140 may include at least one type of storage medium, for example, a flash memory type, a hard disk type, a solid state disk type (SSD type), a silicon disk drive type (SDD type), a multimedia card micro type, a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), and a programmable read-only memory (PROM). The memory 140 may store data and programs required for the calculation operation by the control unit 130. The memory 140 may store data indicating the result of the calculation operation by the control unit 130. Although FIG. 1 shows memory 140 as being physically separate from control unit 130, it is possible for memory 140 to be incorporated within control unit 130.

[0070] The memory 140 may store at least one charging reference map associated with a multi-stage constant current charging protocol for the battery 11. Each charging reference map is described in more detail below.

[0071] The control unit 130 may turn on the relay 20 in response to a key-on signal. The control unit 130 may turn off the relay 20 in response to a key-off signal. The key-off signal indicates switching from a use state to a pause state. Alternatively, the on / off control of the relay 20 may be performed by the vehicle controller 2 instead of the control unit 130.

[0072] While the relay 20 is turned on, the battery 11 is in an in-use state. Conversely, while the relay 20 is turned off, the battery 11 is in a hibernation state. The in-use state indicates a state in which the battery 11 is being charged or discharged, and may also be called a "cycle state." The hibernation state indicates a state in which charging or discharging of the battery 11 is stopped, and may also be called a "calendar state."

[0073] While the battery 11 is in use, the control unit 130 may determine a voltage detection value, a current detection value, a battery temperature detection value, and an outside air temperature detection value based on a voltage signal, a current signal, a battery temperature signal, and an outside air temperature signal, and then determine (estimate) a state of charge (SOC) of the battery 11 based on the voltage detection value, the current detection value, and / or the battery temperature detection value. The SOC is a ratio of remaining capacity to a fully charged capacity (maximum capacity) of the battery 11, and is usually processed in a range of 0 to 1 or 0 to 100%. The SOC may be determined using known methods such as ampere counting, an OCV (Open Circuit Voltage)-SOC curve, and / or a Kalman filter. For reference, a mere description of a "temperature detection value" in this specification may refer to a battery temperature detection value.

[0074] FIG. 2 is a diagram for explaining a first charging reference map used in a charging process using a multi-stage constant current charging protocol.

[0075] Referring to FIG. 2, the first charging reference map CRM1 is a table or function indicating the corresponding relationship of the charging rate to the SOC and temperature of the battery 11, and may be referred to as a "charging rate map."

[0076] Specifically, the first charging reference map CRM1 records a total of M×N charging rates for the first to Mth SOC intervals S#1-S#M and the first to Nth temperature intervals T#1-T#N associated with the multi-stage constant current charging protocol, where M and N are each a natural number equal to or greater than 2.

[0077] Assuming that m is a natural number equal to or less than M and n is a natural number equal to or less than N, the symbol C#m_n used in this specification indicates the charging rate associated with the SOC interval S#m and the temperature interval T#n. Also, the size (width) of the SOC interval S#m is the difference between the start point and the end point of the SOC interval S#m. As an example, in FIG. 2, the start point of the SOC interval S#3 is 20%, the end point is 30%, and the size is 10%. The symbol ΔS#m used in this specification indicates the size of the SOC interval S#m.

[0078] The first to Mth SOC sections S#1 to S#M may be divided from a predetermined overall SOC range as a target for a charging process using a multi-stage constant current charging protocol. That is, the start point of the first SOC section is the same as the start point of the overall SOC range, and the end point of the Mth SOC section S#M is the same as the end point of the overall SOC range associated with the multi-stage constant current charging protocol. The end point of the overall SOC range may be preset as a target SOC. Also, in the first to Mth SOC sections S#1 to S#M, the end point of the preceding section among two adjacent sections may coincide with the start point of the following section. For example, the end point of the first SOC section coincides with the start point of the second SOC section.

[0079] In Fig. 2, the total SOC range is shown as 0 to 100%, M=10, and N=8. That is, a total of 80 charging rates are recorded in the first charging reference map CRM1 for the first to tenth SOC intervals S#1 to S#10 and the first to eighth temperature intervals T#1 to T#8. Meanwhile, in Fig. 2, the magnitudes of the SOC intervals S#1 to S#10 are shown as the same 10%, but this is just an example. That is, at least two of the SOC intervals S#1 to S#10 may be preset to have different magnitudes.

[0080] Let's assume that natural numbers i and j less than M satisfy i < j, and natural numbers x and y less than N satisfy x < y. Looking at the first charging reference map CRM1 shown in Figure 2, in a specific temperature range, the charging rate associated with the SOC range S#j may be less than or equal to the charging rate associated with the SOC range S#i. In one example, in the temperature range T#1, the charging rate C# 10_1 0.2C associated with the SOC range S#10 is 9_1 less than the charging rate C#

[0081] 0.3C associated with the SOC range S#9. 5_3 Also, in a specific SOC range, the charging rate associated with the temperature range T#y may be greater than or equal to the charging rate associated with the temperature range T#x. In one example, in the SOC range S#5, the charging rate C# 5_2 1.2C associated with the temperature range T#3 is

[0082] greater than the charging rate C#

[0083] 1.0C associated with the temperature range T#2.

[0084] Incidentally, in the above examples, it is assumed that the first to eighth temperature ranges T#1 to T#8 are partitioned from a predetermined appropriate temperature range. Therefore, it must be understood that at temperatures lower than the starting point of the temperature range T#1 or higher than the ending point of the temperature range T#8, the change in the charging rate due to temperature and SOC may be different from that in Figure 2. 1_2However, even though the temperature of the battery 11 at the end point of the SOC section S#1 may actually belong to the temperature section T#3 due to the constant current charging in the SOC section S#1, the conventional method assumes that the temperature of the battery 11 remains in the temperature section T#2 even in the SOC section S#2 when predicting the remaining charge time. In this case, the charging rate C# associated with the temperature section T#2 and the SOC section S#2 is 2_2 1.0C, and the charge rate C# associated with the temperature section T#3 and the SOC section S#2 3_3 This difference from 1.2 C, which is the expected charging time, occurs between the predicted time required for charging from the start point to the end point of SOC interval S#2 and the time actually required, by the amount of this difference. Furthermore, it is self-evident that there is a time difference between the predicted value and the actual value in each of the remaining SOC intervals S#3 to S#10 that follow SOC interval S#2, and as the time differences in SOC intervals S#2 to S#10 accumulate, the time difference between the predicted value and the actual value for the total remaining time until the target SOC is reached may become even larger.

[0085] During constant current charging in a specific SOC interval (e.g., S#1), the present invention predicts the battery temperature in the next SOC interval (e.g., S#2), predicts which of N charging rates will be selected in the subsequent SOC interval (e.g., S#2) based on the predicted battery temperature, and predicts the predicted charging time in the SOC interval (e.g., S#2) based on the predicted charging rate. This provides a technical effect that the predicted charging time for each SOC interval from the current SOC interval to the final SOC interval can be calculated closer to the actual value than the conventional method described above.

[0086] FIG. 3 is a schematic diagram for explaining an example of a process for estimating a total remaining time executed by the battery management system 100 shown in FIG.

[0087] Referring to Figs. 1 to 3, S tA and T tAindicates the time when the estimation operation of the total remaining time until the target SOC is performed, that is, the estimated SOC value and the detected temperature value of the battery 11 at the current time, respectively.

[0088] The control unit 130 calculates the SOC estimate S tA and temperature detection value T tA The control unit 130 may identify an SOC interval S#m and a temperature interval T#n to which the estimated SOC value S belongs, and obtain a charging rate C#m_n associated with the SOC interval S#m and the temperature interval T#n from the first charging reference map CRM1. tA For example, the SOC difference ΔS#m between the SOC estimate S tA is 35%, the SOC estimate S tA belongs to SOC section S#4, and the SOC difference ΔS#4 is 10%−5%=5%.

[0089] Next, the control unit 130 divides the capacity corresponding to the SOC difference ΔS#m by the charging rate C#m_n to determine a charging time prediction value Δt#m indicating the remaining time until the SOC of the battery 11 reaches the end point of the SOC section S#m from the current time. As an example, assume that the maximum capacity of the battery 11 is 1,000mAh, the SOC difference ΔS#m is 5%, and the charging rate C#m_n is 1.0C (=1,000mA). Then, the capacity corresponding to the SOC difference ΔS#m is 20mAh, so the charging time prediction value Δt#m=20mAh / 1,000mA=0.02 hours.

[0090] For reference, the maximum capacity of the battery 11 can be estimated by any one or a combination of two or more of various known methods. In one example, the control unit 130 may calculate the current maximum capacity of the battery 11 by dividing an integrated amount of current applied during a period from when the SOC of the battery 11 is at a first value until it reaches a second value by an amount of change in SOC (i.e., a difference between the first value and the second value). Alternatively, the control unit 130 may determine the maximum capacity of the battery 11 by multiplying a State Of Health (SOH) calculated by any one or a combination of two or more of various known methods by a predetermined design capacity (maximum capacity of a new battery).

[0091] Next, the control unit 130 inputs the charging rate C#m_n and the charging time prediction value Δt#m into a thermal model given in advance, and determines a temperature change prediction amount ΔT#m of the battery 11 from the current time until the end point of the SOC section S#m is reached. The thermal model will be described later.

[0092] The control unit 130 calculates the temperature change prediction amount ΔT#m based on the temperature detection value T tA The temperature prediction value T tB As described above, the end point of the SOC section S#m coincides with the start point of the SOC section S#m+1. Therefore, the temperature prediction value T tB also indicates the temperature of the battery 11 when the SOC of the battery 11 later reaches the start point of the SOC interval S#m+1.

[0093] The charging time prediction operation for the SOC section S#m+1 is performed by determining the charging rate using the first charging reference map CRM1. tA Instead of the temperature prediction value T tB Except for the fact that the above is used, the operation is the same as the operation for predicting the charging time predicted value for the SOC section S#m.

[0094] The controller 130 repeats the above process for each SOC interval until the charging time prediction value for the SOC interval to which the target SOC belongs is determined, thereby sequentially determining the charging time prediction value for each of the current SOC interval S#m to the last SOC interval S#M. Thus, by adding up all the charging time prediction values ​​determined for the current SOC interval S#m to the last SOC interval S#M, the total remaining time from the present to the completion of the constant current charging for the last SOC interval S#M can be determined.

[0095] The operation of the thermal model will now be described.

[0096] Inputs to the thermal model include the charge rate, the battery temperature value, and the charge time prediction value. The battery temperature value input to the thermal model can be the temperature detection value obtained using the battery temperature sensor 115 or the temperature prediction value described above. Outputs of the thermal model include the temperature change prediction amount.

[0097] The following formula is an example of a temperature change estimation function that can be used as a thermal model.

[0098] <Formula>

number

[0099] In the above formula, T BAT is the battery temperature value, α is an adjustment coefficient (predetermined), I is the charging current value corresponding to the charging rate, R is the internal resistance value of the battery 11, C H is the heat capacity of the battery 11 (predetermined), Δt is the charging time, T ATM is the outside air temperature value, and β is the heat exchange coefficient (predetermined). Using the example given above with reference to FIG. 3, I, Δt and T in the above formula are BAT are C#m_n (the corresponding current value), Δt#m and T tAWhen is input, ΔT output from the above formula is ΔT#m. For example, if the maximum capacity (buffer capacity) of battery cell C is 1,000mAh (Ampere-hour), a charging rate of 1.0C indicates that the charging current is 1,000mA.

[0100] R and T ATM Each of R and R may be a fixed value given in advance. Alternatively, R may be a variable value that can be adjusted by the control unit 130 according to the charging state of the battery 11. ATM As the temperature, an outside air temperature detection value obtained by using the outside air temperature sensor 117 can be used.

[0101] 4 is a diagram for explaining an exemplary second charging reference map used in a charging process using a multi-stage constant current charging protocol. In explaining the second charging reference map CRM2, overlapping explanations of contents common to the first charging reference map CRM1 will be omitted.

[0102] Referring to FIG. 4, the second charging reference map CRM2 is a table or function indicating the correspondence relationship between the SOC and temperature of the battery 11 and the internal resistance, and may be referred to as a "resistance map."

[0103] A total of M×N internal resistance values ​​for the first to Mth SOC intervals S#1-S#M and the first to Nth temperature intervals T#1-T#N are recorded in the second charging reference map (CRM2). As used herein, the symbol R#m_n denotes an internal resistance value associated with the SOC interval S#m and the temperature interval T#n.

[0104] Similar to the first charging reference map CRM1, Fig. 4 shows a total SOC range of 0 to 100%, M = 10, and N = 8. That is, a total of 80 internal resistance values ​​each associated with a pair of a single SOC section and a single temperature section are recorded in the second charging reference map CRM2.

[0105] 4, it can be seen that in a particular temperature range, the closer the SOC range is to the target SOC (e.g., 100%), the greater the associated internal resistance value tends to be. In one example, in temperature range T#1, the internal resistance value R# associated with SOC range S#10 is 10_1 26.1mΩ is the internal resistance R# associated with SOC section S#9 9_1 Greater than 25.6mΩ.

[0106] In addition, it can be seen that in a particular SOC section, the internal resistance associated with the section tends to gradually decrease as the temperature section becomes relatively higher. For example, in the SOC section S#5, the internal resistance R# associated with the temperature section T#3 is 5_3 6.4mΩ is the internal resistance R# associated with temperature interval T#2 5_2 Less than 11.3mΩ.

[0107] Of course, the correspondence between the SOC and temperature of the battery 11 and the internal resistance depends on the size, weight, active material, external shape, etc. of the battery 11, so FIG. 4 should be understood as merely an example in explaining the present invention.

[0108] Further referring to the above formula, if R in the formula is fixed, the actual internal resistance value during charging of the battery 11 is not taken into consideration at all in predicting the temperature change amount in each temperature range. Therefore, if the internal resistance value reflecting the temperature is not used in predicting the charging time prediction value for each SOC range, a large error may occur between the predicted value and the actual value of the charging time prediction value, as in the conventional method in which the battery temperature value is treated as being maintained constant from the current time. This is a problem that can be easily predicted because the internal resistance value recorded in the second charging reference map CRM2 has a difference of several times to several tens of times depending on the temperature range even in the same SOC range.

[0109] In calculating the predicted temperature change amount for each SOC section that needs to be subjected to the charging process using the multi-stage constant current charging protocol of the present invention, the above-mentioned problems can be significantly improved by using the internal resistance value obtained from the second charging reference map CRM2 as the input variable R for the thermal model exemplified by referring to the above formula.

[0110] FIG. 5 is a schematic diagram for explaining another example of the process of estimating the total remaining time performed by the battery management system shown in FIG.

[0111] The estimation process shown in FIG. 5 differs from the estimation process shown in FIG. 3 in that it further utilizes the internal resistance value obtained from the second charging reference map CRM2. Therefore, the description will be omitted as much as possible from the commonalities with the estimation process described above with reference to FIG. 3, and will focus on the differences between the two estimation processes.

[0112] Referring to FIG. 5 together with FIG. 1 to FIG. 4, S tA and T tA are the current estimated SOC value and detected temperature value of the battery 11, respectively.

[0113] The control unit 130 calculates the SOC estimate S tA and temperature detection value T tA The control unit 130 can obtain the charging rate C#m_n associated with the SOC section S#m and the temperature section T#n to which the charging rate C#m_n belongs from the first charging reference map CRM1. Also, the control unit 130 can obtain the internal resistance value R#m_n associated with the SOC section S#m and the temperature section T#n from the second charging reference map CRM2.

[0114] Next, after determining the predicted charging time value Δt#m, the control unit 130 further inputs the internal resistance value R#m_n together with the charging rate C#m_n and the predicted charging time value Δt#m into a thermal model to determine a predicted temperature change amount ΔT#m.

[0115] The control unit 130 calculates the temperature change prediction amount ΔT#m based on the temperature detection value T tA The temperature prediction value T tBDetermine.

[0116] The charging time prediction operation for the SOC section S#m+1 following the current SOC section S#m is performed by determining the charging rate using the first charging reference map CRM1. tA Instead of the temperature prediction value T tB Except for the use of the above, the operation of estimating the charging time predicted value for the SOC section S#m is the same as that of the above.

[0117] On the other hand, in parallel with or instead of the operation of estimating the internal resistance value using the second charging reference map CRM2, the current outside air temperature detected by the outside air temperature sensor 117 is used as a thermal model T ATM may be entered as

[0118] Unlike the battery temperature, the outside air temperature usually does not change significantly during charging of the battery 11. Therefore, whenever determining a predicted temperature change amount for each SOC section in which the charging process will be performed from the current time point onwards, the outside air temperature value detected by the outside air temperature sensor 117 at the start of charging (or the current time point) may be repeatedly input to the thermal model in the same manner.

[0119] Fig. 6 is a flowchart showing a method for predicting a battery charging time according to a first embodiment of the present invention. The method of Fig. 6 can be performed by the battery management system 100 at set time intervals during charging of the battery 11 using a multi-stage constant current charging protocol. In the method of Fig. 6, only the first charging reference map CRM1 of the first charging reference map CRM1 and the second charging reference map CRM2 is used.

[0120] 1 to 4 and 6, in step S610, the control unit 130 determines an estimated SOC value of the battery 11 based on the detected voltage value, current value, and battery temperature value of the battery 11. The control unit 130 records the detected voltage value, current value, temperature value, and SOC estimated value, which are determined at every set time, in the memory 140. In step S610, the detected outside air temperature value TATM can further be determined.

[0121] In step S620, the control unit 130 determines, from the first charging reference map CRM1 associated with the multi-stage constant current charging protocol, the mth SOC interval (S#m, m is a natural number equal to or less than M) to which the estimated SOC value of the battery 11 belongs and the mth charging rate C#m_n associated with the temperature interval T#n to which the detected temperature value belongs. The mth SOC interval S#m is the current SOC interval, and the mth charging rate may indicate the magnitude of the charging current used for constant current charging in the mth SOC interval S#m.

[0122] In step S630, the control unit 130 determines a predicted charging time value in the mth SOC interval S#m based on the mth charging rate C#m_n and the SOC difference ΔS#m between the SOC estimated value and the end point of the mth SOC interval S#m.

[0123] In step S640, the control unit 130 determines a temperature prediction value at the end point of the mth SOC section S#m based on the mth charging rate C#m_n and the mth charging time prediction value in the mth SOC section S#m. ATM If it is determined that the outside air temperature detection value T ATM A temperature prediction value at the end point of the m-th SOC interval S#m may be determined based further on the above.

[0124] The above-mentioned step S640 may be performed on the condition that m is less than M. m being less than M means that there is at least one SOC interval remaining following the mth SOC interval S#m in which the charging process is currently in progress. That is, if the mth SOC interval S#m is not the Mth SOC interval S#M, step S640 may be performed.

[0125] Step S640 may include step S642 and step S644.

[0126] In step S642, the control unit 130 uses a predetermined thermal model to determine a predicted temperature change ΔT#m from the SOC estimated value to the end point of the mth SOC interval S#m based on the mth charging rate C#m_n and the predicted charging time in the mth SOC interval S#m.

[0127] In step S644, the control unit 130 sums the temperature change prediction amount ΔT#m from the SOC estimated value to the end point of the m-th SOC interval S#m to the temperature detection value to determine the temperature prediction value at the end point of the m-th SOC interval S#m.

[0128] Fig. 7 is a flow chart showing a method for predicting a battery charging time according to a second embodiment of the present invention. The method of Fig. 7 can be performed by the battery management system 100 at set time intervals during charging of the battery 11 using a multi-stage constant current charging protocol. In the method of Fig. 7, both the first charging reference map CRM1 and the second charging reference map CRM2 are used.

[0129] 1 to 5 and 7, in step S710, the control unit 130 determines an estimated SOC value of the battery 11 based on the detected voltage value, current value, and battery temperature value of the battery 11. Step S710 is substantially the same as step S610.

[0130] In step S720, the control unit 130 determines an m-th charging rate C#m_n associated with an m-th SOC interval S#m to which the estimated SOC value of the battery 11 belongs and a temperature interval T#n to which the detected temperature value belongs, from the first charging reference map CRM1 associated with the multi-stage constant current charging protocol. Step S720 is substantially the same as step S620.

[0131] In step S722, the control unit 130 determines an m-th internal resistance value R#m_n associated with the m-th SOC section S#m and the temperature section T#n to which the detected temperature value belongs in the second charging reference map CRM2.

[0132] In step S730, the control unit 130 determines a charging time prediction value in the m-th SOC interval S#m based on the m-th charging rate C#m_n and the SOC difference (ΔS#m) between the SOC estimation value and the end point of the m-th SOC interval S#m. Step S730 is substantially the same as step S630.

[0133] In step S740, the control unit 130 determines a temperature prediction value at the end point of the mth SOC section S#m based on the mth charging rate C#m_n, the charging time prediction value in the mth SOC section S#m, and the mth internal resistance value R#m_n. ATM If it is determined that the outside air temperature detection value T ATM A temperature prediction value at the end point of the m-th SOC interval S#m may be determined based further on: Similar to step S640 described above, step S740 may be performed on the condition that I is less than M.

[0134] Step S740 may include step S742 and step S744.

[0135] In step S742, the control unit 130 uses a predetermined thermal model to determine a predicted temperature change ΔT#m from the estimated SOC value to the end point of the mth SOC interval S#m based on the mth charging rate C#m_n, the predicted charging time in the mth SOC interval S#m, and the mth internal resistance value R#m_n.

[0136] In step S744, the control unit 130 sums the temperature change prediction amount ΔT#m from the SOC estimated value to the end point of the m-th SOC interval S#m to the temperature detection value to determine the temperature prediction value at the end point of the m-th SOC interval S#m.

[0137] Fig. 8 is a flow chart showing a method for predicting a battery charging time according to a third embodiment of the present invention. The method of Fig. 8 can be performed following the method of Fig. 6 or the method of Fig. 7, on the condition that m is less than M. In the method of Fig. 8, only the first charging reference map CRM1 is used among the first charging reference map CRM1 and the second charging reference map CRM2.

[0138] 1 to 8, in step S810, the control unit 130 sets the section index k to be equal to m+1.

[0139] In step S820, the controller 130 determines whether the determination of the predicted charging time value in the k-1th SOC interval S#k-1 and the predicted temperature value at the end point of the k-1th SOC interval S#k-1 is completed. If the value of step S820 is 'YES', the controller 130 proceeds to step S830.

[0140] In step S830, the control unit 130 determines the kth charging rate associated with the temperature section to which the temperature prediction values ​​at the end points of the kth SOC section S#k and the k-1st SOC section S#k-1 belong in the first charging reference map CRM1.

[0141] In step S840, the control unit 130 determines a predicted charging time value in the kth SOC interval S#k and a predicted temperature value at the end point of the kth SOC interval S#k based on the kth charging rate and the magnitude of the kth SOC interval S#k.

[0142] Step S840 may include step S842 and step S844.

[0143] In step S842, the control unit 130 determines a predicted amount of temperature change in the kth SOC zone S#k based on the kth charging rate and the predicted charging time in the kth SOC zone S#k using a predefined thermal model.

[0144] In step S844, the control unit 130 adds the predicted temperature change amount in the kth SOC interval S#k to the predicted temperature value at the end point of the k-1th SOC interval S#k-1 to determine the predicted temperature value at the end point of the kth SOC interval S#k.

[0145] In step S850, the control unit 130 determines whether the interval index k is equal to M. M can be said to be an identification number of the last SOC interval S#M to which the target SOC belongs. If the interval index k is equal to M, it means that the determination of the predicted charging time value for the last SOC interval S#M is completed. If the value of step S850 is "No", the control unit 130 proceeds to step S852, increments the interval index k by 1, and then returns to step S820. That is, the above-mentioned steps S820 to S852 may be repeated until k is increased from m+1 to M.

[0146] If the value of step S850 is "YES", proceed to step S860.

[0147] In step S860, the control unit 130 sums the mth to Mth charging time prediction values ​​to determine the total remaining time until the charging process using the multi-stage constant current charging protocol is completed (i.e., until the SOC of the battery reaches the target SOC). The mth to Mth charging time prediction values ​​correspond one-to-one to the mth to Mth SOC ranges S#m to S#M.

[0148] Fig. 9 is a flow chart showing a method for predicting a battery charging time according to a fourth embodiment of the present invention. The method of Fig. 9 may be performed following the method of Fig. 6 or the method of Fig. 7 on the condition that m, which is a section index of the SOC section S#m in which a charging process is currently in progress, is less than M. In the method of Fig. 9, both the first charging reference map CRM1 and the second charging reference map CRM2 are used.

[0149] 1 to 7 and 9, in step S910, the control unit 130 sets an interval index k equal to m+1. Step S910 is substantially the same as step S810.

[0150] In step S920, the controller 130 determines whether the determination of the charging time prediction value in the k-1th SOC interval S#k-1 and the temperature prediction value at the end point of the k-1th SOC interval S#k-1 is completed. Step S920 is substantially the same as step S820.

[0151] In step S930, the control unit 130 determines a k-th charging rate associated with a temperature section to which the temperature prediction values ​​at the end points of the k-th SOC section S#k and the k-1st SOC section S#k-1 belong in the first charging reference map CRM1. Step S930 is substantially the same as step S830.

[0152] In step S932, the control unit 130 determines the kth internal resistance value associated with the temperature section to which the temperature prediction values ​​at the end points of the kth SOC section S#k and the k-1st SOC section S#k-1 belong in the second charging reference map CRM2.

[0153] In step S940, the control unit 130 determines a predicted charging time value in the kth SOC interval S#k and a predicted temperature value at the end point of the kth SOC interval S#k based on the kth charging rate, the magnitude of the kth SOC interval S#k, and the kth internal resistance value.

[0154] Step S940 may include step S942 and step S944.

[0155] In step S942, the control unit 130 determines a predicted amount of temperature change in the kth SOC section S#k based on the kth charging rate, the predicted charging time in the kth SOC section S#k, and the kth internal resistance value using a predetermined thermal model.

[0156] In step S944, the control unit 130 adds the predicted temperature change amount in the kth SOC interval S#k to the predicted temperature value at the end point of the k-1th SOC interval S#k-1 to determine the predicted temperature value at the end point of the kth SOC interval S#k.

[0157] In step S950, the control unit 130 determines whether the section index k is equal to M. If the value of step S950 is "No", the control unit 130 proceeds to step S952. If the value of step S950 is "No", the control unit 130 proceeds to step S952, increments the section index k by 1, and then returns to step S920. If the value of step S950 is "Yes", the control unit 130 proceeds to step S960. Steps S950 and S952 are substantially the same as steps S850 and S852.

[0158] In step S960, the control unit 130 sums the mth to Mth charging time prediction values ​​to determine a total remaining time until the charging process using the multi-stage constant current charging protocol is completed. Step S960 is substantially the same as step S860.

[0159] 10 is a flow chart showing a method for predicting a battery charging time according to a fifth embodiment of the present invention. The method of FIG 10 can be performed to adjust the SOC range on the condition that the constant current charging for each SOC range, for which a charging time prediction value is determined according to any one of the first to fourth embodiments described above with reference to FIG 6 to FIG 9, is actually completed.

[0160] 1 to 10, in step S1010, the control unit 130 determines an actual temperature change amount in the m-th SOC section S#m. If the m-th SOC section S#m is an SOC section at the start of charging using a multi-stage constant current charging protocol, a difference between a battery temperature detection value at the start of charging and a battery temperature detection value at an end point of the m-th SOC section S#m may be determined as an actual temperature change amount in the m-th SOC section S#m. If the m-th SOC section S#m is an SOC section subsequent to the SOC section at the start of charging, a difference between two battery temperature detection values ​​at the start and end points of the m-th SOC section S#m may be determined as an actual temperature change amount in the m-th SOC section S#m.

[0161] In step S1020, the controller 130 determines whether the actual temperature change amount in the m-th SOC section S#m is greater than the predicted temperature change amount in the m-th SOC section S#m. If the value of step S1020 is 'Yes', the controller 130 proceeds to step S1030.

[0162] In operation S1030, the control unit 130 adjusts the mth SOC section S#m according to a difference between an actual temperature change amount and a predicted temperature change amount in the mth SOC section S#m.

[0163] In one example, the controller 130 may decrease the end point of the mth SOC section S#m by an adjustment value having a predetermined amount of inter-layer relationship with respect to the difference. As a result, the size of the mth SOC section S#m decreases by the adjustment value. Also, when m is less than M, the end point of the mth SOC section S#m being moved up by the adjustment value means that the start point of the m+1th SOC section S#m+1 is also moved up by the adjustment value. Therefore, the size of the m+1th SOC section S#m+1 increases by the adjustment value.

[0164] Although only the section index m has been described in FIG. 10, the same can be commonly applied to the remaining section indexes less than or equal to M.

[0165] According to the fifth embodiment described above with reference to Fig. 10, the charging process for the SOC section where the temperature rise exceeds the expected level is terminated early, while the charging process for the SOC section following the SOC section is started early. As can be seen from the first charging reference map CRM1 described above with reference to Fig. 3, if the first charging reference map CRM1 is created to have a tendency that a relatively low charging rate is associated with a relatively high SOC section, the charging rate that induces the excessive temperature rise can be switched to another lower charging rate early, and the charging process using the multi-stage constant current charging protocol can be safely continued. As a result, a technical effect is achieved in which the first charging reference map CRM1 is corrected to prevent overheating of the battery 11 due to charging.

[0166] In addition, the control unit 130 may also correct the second charge reference map CRM2 to correspond to the correction of the first charge reference map CRM1. For example, when a specific SOC section of the first charge reference map CRM1 is adjusted, the specific SOC section of the second charge reference map CRM2 may also be adjusted to the same extent.

[0167] The embodiments of the present invention described above may not necessarily be embodied through an apparatus and method, but may be embodied through a program that realizes functions corresponding to the configuration of the embodiments of the present invention or a recording medium on which the program is recorded, and such implementation should be easily embodied by a person skilled in the art to which the present invention pertains from the description of the above-mentioned embodiments.

[0168] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and various modifications and variations can be made by those having ordinary skill in the art to which the present invention pertains within the scope of the technical spirit of the present invention and the scope of the claims.

[0169] Furthermore, since the above-mentioned invention can be variously replaced, modified, and altered by a person having ordinary knowledge in the technical field to which the invention belongs without departing from the technical concept of the invention, it is not limited to the above-mentioned embodiments and the attached drawings, and can be configured by selectively combining all or part of each embodiment to make various modifications.

Claims

1. a memory for storing a first charging reference map in which charging rates for first to Mth SOC intervals (M is a natural number equal to or greater than 2) and first to Nth temperature intervals (N is a natural number equal to or greater than 2) associated with a multi-stage constant current charging protocol are recorded; a sensing unit for detecting the voltage, current and temperature of the battery; a control unit that determines an estimated SOC value of the battery based on a voltage detection value, a current detection value, and a temperature detection value at a predetermined time interval from a start point of a charging process for the battery; Including, The control unit is determining an m-th charging rate associated with an m-th SOC interval (m is a natural number equal to or less than M) to which the SOC estimation value belongs and a temperature interval to which the temperature detection value belongs in the first charging reference map; determining a charging time prediction value for the m SOC section based on the m charging rate and an SOC difference between the SOC estimation value and an end point of the m SOC section; if m is less than M, further configured to determine a temperature prediction value at an end point of the m SOC interval; A battery management system, wherein a temperature prediction value at an end point of the mth SOC interval indicates a temperature of the battery at a start point of an m+1th SOC interval.

2. The control unit is determining a predicted amount of temperature change from the estimated SOC value to an end point of the m SOC interval based on the m charging rate and a predicted charging time value in the m SOC interval using a predetermined thermal model; 2. The battery management system of claim 1, configured to sum a predicted temperature change amount from the estimated SOC value to an end point of the m SOC interval to the detected temperature value to determine a predicted temperature value at the end point of the m SOC interval.

3. The memory includes: Further storing a second charging reference map in which M×N internal resistance values ​​for the first to Mth SOC ranges and the first to Nth temperature ranges are recorded; The control unit is determining an mth internal resistance value associated with the mth SOC range and a temperature range to which the temperature detection value belongs from the second charging reference map; determining a predicted amount of temperature change from the estimated SOC value to an end point of the m SOC section based on the m charging rate, a predicted charging time value in the m SOC section, and the m internal resistance value, using a predetermined thermal model; 2 . The battery management system of claim 1 , further comprising: a temperature change prediction amount from the estimated SOC value to an end point of the mth SOC interval added to the detected temperature value to determine a temperature prediction value at the end point of the mth SOC interval.

4. The control unit is When the charging process for the m SOC section is completed, The battery management system of claim 3 , further comprising: comparing a predicted temperature change from the estimated SOC value to an end point of the mth SOC interval with an actual temperature change to adjust the mth SOC interval.

5. The control unit is Let k be a natural number greater than or equal to m+1 and less than or equal to M. When the determination of the charging time prediction value in the k-1th SOC section and the temperature prediction value at the end point of the k-1th SOC section is completed, determining a kth charging rate associated with a temperature interval to which a temperature prediction value at an end point of a kth SOC interval and the k-1th SOC interval belongs in the first charging reference map; 2 . The battery management system according to claim 1 , further comprising: determining a charging time prediction value in the kth SOC interval and a temperature prediction value at an end point of the kth SOC interval based on the kth charging rate and the magnitude of the kth SOC interval.

6. The control unit is When the determination of the charging time prediction value in the M SOC section is completed, 6. The battery management system of claim 5, further comprising: a sum of charging time prediction values ​​determined for the mth to Mth SOC intervals to determine a remaining time until the charging process using the multi-stage constant current charging protocol is completed.

7. The control unit is When the determination of the charging time prediction value in the k-1 SOC section and the temperature prediction value at the end point of the k-1 SOC section is completed, determining a predicted amount of temperature change in the kth SOC section based on the kth charging rate and a predicted charging time value in the kth SOC section using a predetermined thermal model; 6. The battery management system of claim 5, further comprising: a temperature prediction value at an end point of the kth SOC interval being determined by adding a predicted temperature change amount in the kth SOC interval to a predicted temperature value at an end point of the kth-1th SOC interval.

8. The memory includes: The method is further configured to store a second charging reference map in which M×N internal resistance values ​​for the first to M SOC ranges and the first to N temperature ranges are recorded, The control unit is determining, from the second charging reference map, a kth internal resistance value associated with a temperature interval to which the temperature prediction values ​​at the end points of the kth SOC interval and the k-1th SOC interval belong; determining a predicted amount of temperature change in the kth SOC section based on the kth charging rate, the kth charging time predicted value, and the kth internal resistance value; 6. The battery management system of claim 5, configured to sum a predicted amount of temperature change in the kth SOC interval to a predicted temperature value at an end point of the kth SOC interval and the k-1th SOC interval to determine a predicted temperature value at an end point of the kth SOC interval.

9. The control unit is When the charging process for the kth SOC section is completed, The battery management system of claim 5 , further comprising: comparing a predicted temperature change in the kth SOC zone with an actual temperature change to adjust the kth SOC zone.

10. A battery pack comprising the battery management system according to any one of claims 1 to 9.

11. An electric vehicle comprising the battery pack of claim 10.

12. A method for predicting a battery charging time performed at a predetermined time interval from the start of a charging process for a battery, comprising: determining an estimated SOC value of the battery based on a voltage detection value, a current detection value, and a temperature detection value of the battery; determining an m-th SOC interval (m is a natural number equal to or less than M) to which the SOC estimated value belongs and an m-th charging rate associated with a temperature interval to which the temperature detection value belongs from a first charging reference map in which charging rates for first to M-th SOC intervals and first to N-th temperature intervals associated with a multi-stage constant current charging protocol are recorded; determining a charging time prediction value in the m SOC range based on the m charging rate and an SOC difference between the estimated SOC value and an end point of the m SOC range; If m is less than M, determining a temperature prediction value at an end point of the mth SOC interval; A method for predicting a charging time for a battery, wherein the predicted temperature value at the end point of the mth SOC interval indicates the temperature of the battery at the start point of an m+1th SOC interval.

13. The step of determining an m-th predicted charging time value in the m-th SOC section includes: determining a temperature change prediction amount from the estimated SOC value to an end point of the m SOC interval based on the m charging rate and a charging time prediction value in the m SOC interval using a predetermined thermal model; and summing a predicted amount of temperature change from the estimated SOC value to an end point of the m SOC interval with the detected temperature value to determine a predicted temperature value at the end point of the m SOC interval.

14. Let k be a natural number greater than or equal to m+1 and less than or equal to M. When the determination of the charging time prediction value in the k-1-th SOC range and the temperature prediction value at the end point of the k-1-th SOC range is completed, determining a k-th charging rate associated with a temperature range to which the k-th SOC range and the temperature prediction value at the end point of the k-1-th SOC range belong in the first charging reference map; 13. The method of claim 12, further comprising: determining a charging time prediction value in the kth SOC interval and a temperature prediction value at an end point of the kth SOC interval based on the kth charging rate and the magnitude of the kth SOC interval.

15. When the determination of the charging time prediction value in the M SOC section is completed, 15. The method of claim 14, further comprising determining a remaining time until a charging process using the multi-stage constant current charging protocol is completed by summing the charging time prediction values ​​determined for the mth to Mth SOC intervals.

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