Apparatus and method for pre-sensing thermal runaway using BMS having EIS function

Abstract

The present invention relates to an apparatus and a method for pre-sensing thermal runaway using a battery management system (BMS) having an electrochemical impedance spectroscopy (EIS) function, and more particularly, to an apparatus and a method for pre-sensing thermal runaway using a BMS having an EIS function, which, when a thermal runaway prediction event occurs, can detect thermal runaway in advance using a battery management system (BMS) having an EIS function, and to a method for pre-sensing thermal runaway using a battery management system (BMS) having an EIS function, and to a method for pre-sensing thermal runaway in advance using a battery management system (BMS) having an EIS function, and to a method for pre-sensing thermal runaway in advance using a battery management system (BMS) having an EIS function. A rapid diagnosis mode in which impedance is measured using only one preset frequency among a plurality of impedance measurement frequencies of an EIS of a module BMS is set, and in the rapid diagnosis mode, the impedance of a cell of each battery module at the set frequency is simultaneously measured by the EIS. And predicting the possibility of thermal runaway according to the variation deviation of the measured impedance to give an alarm.

Description

Technical Field

[0001] This invention relates to a thermal runaway pre-sensing device and method using a battery management system (BMS) with electrochemical impedance spectroscopy (EIS) functionality. More specifically, it relates to a thermal runaway pre-sensing device and method using a BMS with EIS functionality, which, when a thermal runaway prediction event occurs, is set to a rapid diagnostic mode that uses only a preset frequency among multiple impedance measurement frequencies of the module BMS's EIS to measure impedance. In the rapid diagnostic mode, the impedance of each cell in the battery module is simultaneously measured at the preset frequency using the EIS, and the possibility of thermal runaway is predicted based on the deviation of the measured impedance to issue an alarm. Background Technology

[0002] In recent years, electric bicycles, electric scooters, electric cars, and advanced air mobility (AAM) technologies, including urban air mobility (UAM) and regional air mobility (RAM), have been researched, developed, and are rapidly evolving. Among them, electric bicycles, electric scooters, and electric cars have been commercialized and applied in real life, and are ubiquitous in our surroundings.

[0003] Typically, these vehicles utilize batteries of various types and sizes to reduce environmental pollution and operating costs.

[0004] As mentioned above, with batteries being used in various types of vehicles, countless waste batteries are being generated, and even more are expected to be generated in the future.

[0005] Therefore, since these batteries can be used for general energy storage purposes but not for transportation, efforts are being made to develop waste battery recycling systems to reuse waste batteries generated in vehicles. A representative system is the Energy Storage System (ESS), which stores the generated renewable energy in waste batteries.

[0006] Typically, this type of battery uses lithium-ion batteries.

[0007] Lithium-ion batteries convert chemical energy into electrical energy through oxidation and reduction reactions between the positive (+) and negative (-) electrodes. The positive (+) electrode of a lithium-ion battery is composed of lithium oxide (Li+O), which combines lithium and oxygen, making it susceptible to fire and explosion.

[0008] In existing lithium-ion battery-based systems, fires and explosions are detected by installing OFF-CAS sensors, smoke sensors, thermal imaging cameras, and other devices to respond quickly.

[0009] However, existing OFF-CAS sensors, smoke sensors, thermal imaging cameras, and other devices related to thermal runaway all detect thermal runaway after it has occurred. Therefore, they cannot prevent fires and explosions, nor can they ensure sufficient time to reduce the spread of fire.

[0010] In addition, existing battery management systems (BMS) for lithium-ion batteries monitor and manage cell charging and discharging, overcharging, temperature, etc.

[0011] Figure 1 This diagram illustrates the battery configuration of a typical battery pack or ESS rack unit, showing the battery modules connected in series. Figure 2 This is a graph showing the thermal runaway curve based on normal voltage.

[0012] Reference Figure 1 and Figure 2 Typically, a battery pack, ESS rack unit, etc., includes: one or more (m=1, 2, 3...) battery modules 20, including multiple (battery) cells 40, and multiple (n) module BMS 30 for monitoring cells in units of a predetermined number of cells; and a main BMS 10, which collects the voltage, current, temperature, etc. of the battery module 20 units collected by the battery module 20, and performs charging and discharging management, overcharge management, and abnormal state management of the battery module 20.

[0013] like Figure 1 As shown, depending on the characteristics of the system to be configured, multiple battery modules 20 can be connected in series or in parallel.

[0014] like Figure 1 As shown, each module BMS 30 of the battery module 20 measures the voltage and current of each of the 16 cells 40, and monitors the cells 40 under its responsibility in sequence by means of temperature sensors 50 arranged at intervals in a specific number (e.g., 3 to 4), while also monitoring the temperature of the cells 40 on which the temperature sensors 50 are installed.

[0015] However, as Figure 2As shown, since thermal runaway and fire occur due to a rapid and sudden rise in temperature, when thermal runaway and fire occur in cell 40 without a temperature sensor, the existing main BMS 10 cannot detect the fire until it spreads to cell 40 with a temperature sensor 50. It can only detect it after the thermal runaway and fire have occurred, thus limiting it to post-event measures and resulting in the problem of ineffective detection of thermal runaway and fire.

[0016] As mentioned above, existing BMS systems cannot prevent fires caused by thermal runaway in advance; they can only perform post-event sensing. Therefore, there is a problem that when a battery fire occurs, it may spread into a larger fire. Summary of the Invention

[0017] (a) Technical problems to be solved Therefore, the purpose of this invention is to provide a thermal runaway pre-sensing device and method using a BMS with EIS function. When a thermal runaway prediction event occurs, the device is set to a rapid diagnostic mode that uses only a preset frequency among multiple impedance measurement frequencies of the module BMS's EIS to measure impedance. In the rapid diagnostic mode, the impedance of each cell of the battery module is simultaneously measured by the EIS at the preset frequency, and the possibility of thermal runaway is predicted based on the deviation of the measured impedance to issue an alarm.

[0018] (II) Technical Solution To achieve the objectives described above, the thermal runaway pre-sensing device utilizing a BMS with EIS functionality according to the present invention is characterized by comprising: a battery module including a plurality of battery cells and a plurality of module BMSs, the plurality of module BMSs being connected to a predetermined number of battery cells among the plurality of battery cells, and including an EIS measurement unit that uses EIS with multiple frequencies to measure the impedance of the connected battery cells, to monitor the impedance of the battery cells, and to set the module BMS to a fast diagnostic mode when a fast diagnostic mode is requested, thereby measuring the impedance of the battery cells using one of the frequencies of the EIS, namely the fast diagnostic mode frequency; and a main BMS that monitors the occurrence of a thermal runaway diagnostic event, and when a thermal runaway diagnostic event occurs, controls the module BMS to be set to a fast diagnostic mode, and in the fast diagnostic mode, measures the impedance of the battery cells of the battery module using the fast diagnostic mode frequency, and when the measured impedance exceeds a reference value and the amount of impedance change exceeds a reference change, predicts that thermal runaway will occur in the battery module including the battery cells and issues an alarm.

[0019] The battery module's module BMS is characterized by defining a fast diagnostic mode frequency, and setting it to the fast diagnostic mode when receiving a fast diagnostic mode setting request from the main BMS.

[0020] The main BMS is characterized in that it defines the rapid diagnostic mode frequency, and when a thermal runaway diagnostic event occurs, it sends a rapid diagnostic mode setting request message including the rapid diagnostic mode frequency information to the module BMS to request the setting of the rapid diagnostic mode. The module BMS is characterized in that when a rapid diagnostic mode setting request occurs due to receiving the rapid diagnostic mode setting request message, it defines the frequency of the rapid diagnostic mode frequency information included in the rapid diagnostic mode setting request message as the rapid diagnostic mode frequency to set the rapid diagnostic mode.

[0021] The main BMS is characterized in that when the battery module is fully charged, it is determined that the thermal runaway diagnostic event has occurred.

[0022] The main BMS is characterized in that the impedance of the same sequence of cells in each module BMS is simultaneously measured for a predetermined number of cells connected to each module BMS.

[0023] The main BMS is characterized in that when the impedance measured in a specific cell exceeds a reference value and is judged as abnormal, the number of repeated measurements and the period for the cell are set, and the impedance of the cell is repeatedly measured at the period within the number of repeated measurements, so that when the change in impedance exceeds the reference change, thermal runaway is predicted to occur.

[0024] The main BMS is characterized in that, after determining that the cell is abnormal, when the measured impedance is less than or equal to the reference value, the number of repeated measurements is reduced, and when the impedance is repeatedly measured to be less than or equal to the reference value, causing the number of repeated measurements to become zero (0), the system is set to a normal state.

[0025] To achieve the objectives described above, the thermal runaway pre-sensing method using a BMS with EIS functionality according to the present invention is characterized by comprising: a rapid diagnostic mode setting step, wherein when a thermal runaway diagnostic event occurs, the main BMS control module BMS is set to rapid diagnostic mode; an impedance measurement step, wherein the module BMS measures the impedance of the battery cell using EIS, and measures the impedance of the battery cell at a frequency of rapid diagnostic mode, i.e., the rapid diagnostic mode frequency, to provide the impedance to the main BMS, wherein the module BMS connects a predetermined number of battery cells among the plurality of battery cells, and includes an EIS measurement unit that measures the impedance of the connected battery cells using EIS that measures impedance at multiple frequencies; and a thermal runaway monitoring step, wherein in rapid diagnostic mode, the main BMS measures the impedance of the battery cell of the battery module at the rapid diagnostic mode frequency, and when the measured impedance exceeds a reference value and the amount of impedance change exceeds the reference change, predicts that thermal runaway will occur in the battery module including the battery cell and issues an alarm.

[0026] The rapid diagnostic mode setting step is characterized by including: a rapid diagnostic mode setting request step, in which the main BMS sends a rapid diagnostic mode setting request message to the module BMS when a thermal runaway diagnostic event occurs; and a rapid diagnostic mode setting step, in which the module BMS sets a preset frequency among multiple frequencies of EIS as the rapid diagnostic mode frequency to set the rapid diagnostic mode.

[0027] The rapid diagnostic mode setting step is characterized by including: a rapid diagnostic mode setting request step, wherein when a thermal runaway diagnostic event occurs, the main BMS sends a rapid diagnostic mode setting request message including rapid diagnostic mode frequency information to the module BMS to request the setting of the rapid diagnostic mode; and a rapid diagnostic mode setting step, wherein when the module BMS receives the rapid diagnostic mode setting request message from the main BMS, it sets the frequency of the rapid diagnostic mode frequency information in the rapid diagnostic mode setting request message to the rapid diagnostic mode frequency of the EIS measurement unit to set the rapid diagnostic mode.

[0028] The rapid diagnostic mode setting step is characterized by further including: a thermal runaway diagnostic event monitoring step, wherein the main BMS monitors whether the battery module is fully charged, and when the battery module is fully charged, it is determined that the thermal runaway diagnostic event has occurred. In the thermal runaway diagnostic event monitoring step, when the thermal runaway diagnostic event occurs, the main BMS executes the rapid diagnostic mode setting request step.

[0029] The module BMS is characterized in that, in the impedance measurement step, for a predetermined number of connected cells, the impedance of cells in the same order as those in other module BMSs is measured synchronously with the control of the main BMS and sent to the main BMS.

[0030] The module BMS is characterized in that the impedance measurement sequence is determined according to the series connection sequence of the cells connected to the module BMS.

[0031] The thermal runaway monitoring step is characterized by including: a centralized monitoring setting step, in the rapid diagnostic mode, when the impedance measured in a specific cell exceeds a reference value and is judged as abnormal, the main BMS sets the number of repeated measurements and the cycle for the cell; and a thermal runaway prediction step, within the number of repeated measurements, the main BMS repeatedly measures the impedance of the cell at the cycle, thereby predicting that thermal runaway will occur when the change in impedance exceeds the reference change.

[0032] The thermal runaway monitoring step is characterized by further including: a thermal runaway error prevention step, wherein after determining that the cell is abnormal, when the measured impedance is less than or equal to the reference value, the main BMS reduces the number of repeated measurements, and when the impedance is repeatedly measured to be less than or equal to the reference value, causing the number of repeated measurements to become zero (0), the system is set to a normal state.

[0033] (III) Beneficial Effects The advantage of this invention is that it can detect abnormal regions based on the impedance of each cell measured by a module BMS with impedance measurement function utilizing EIS, and can predict whether thermal runaway will occur in the abnormal regions.

[0034] In addition, the present invention has the advantage that even when an abnormal range is detected, it can determine whether thermal runaway will progress or will progress normally by tracking more than a predetermined number of times, thereby preventing false predictions of thermal runaway caused by temporary impedance anomalies.

[0035] In addition, the advantage of this invention is that, for multiple battery modules, the impedance of cells in the same order can be measured simultaneously, thereby enabling thermal runaway prediction.

[0036] In addition, the advantage of the present invention is that when a thermal runaway diagnostic event occurs, it is set to a fast diagnostic mode that uses only one preset frequency among the multiple frequencies used for impedance measurement using EIS. In the fast diagnostic mode, only the preset frequency is used to measure impedance, so multiple cells can be checked more quickly to see if thermal runaway has occurred.

[0037] Furthermore, in this invention, a relatively high frequency among the multiple impedance measurement frequencies of EIS is preferably used in the rapid diagnostic mode. However, test results show that any frequency among all impedance measurement frequencies can detect the possibility of thermal runaway. Therefore, the advantage of this invention is that, by setting a relatively high frequency to measure impedance, the possibility of thermal runaway can be checked more quickly. Attached Figure Description

[0038] Figure 1 This is a diagram showing the battery configuration of a typical battery pack or ESS rack unit.

[0039] Figure 2 This is a graph showing the thermal runaway curve based on normal voltage.

[0040] Figure 3 This diagram illustrates the configuration of a battery system according to the present invention, which is equipped with a thermal runaway pre-sensing device utilizing a BMS with EIS functionality.

[0041] Figure 4It shows the curves according to the invention, which represent the voltage and temperature changes over time, the impedance changes caused by the voltage and temperature changes, and the time points at which thermal runaway occurs.

[0042] Figure 5 The curves show the impedance changes of the EIS at each frequency under overcharge and overtemperature conditions according to an embodiment of the present invention.

[0043] Figure 6 This is a flowchart illustrating a thermal runaway pre-sensing method using a BMS with EIS functionality according to the present invention. Detailed Implementation

[0044] Hereinafter, with reference to the accompanying drawings, the configuration of the thermal runaway early sensing device of the battery system according to the present invention utilizing a BMS with EIS function will be described, and the thermal runaway early sensing method in the thermal runaway early sensing device will also be described.

[0045] Figure 3 This diagram illustrates the configuration of a battery system according to the present invention, equipped with a thermal runaway pre-sensing device utilizing a BMS with EIS functionality. Figure 4 This is a curve showing the time points of thermal runaway caused by voltage and temperature changes over time, impedance changes caused by voltage and temperature changes, and the time of thermal runaway according to the present invention. Figure 5 These are curves illustrating the impedance changes of the EIS at each frequency under overcharge and overtemperature conditions according to an embodiment of the present invention. Hereinafter, refer to... Figures 3 to 5 Please provide an explanation.

[0046] The thermal runaway pre-sensing device utilizing a BMS with EIS functionality according to the present invention includes a main BMS 100 and multiple battery modules 200. For example... Figure 3 As shown, the main BMS 100 and multiple battery modules 200 can be connected in series or in parallel.

[0047] The battery module 200 according to the present invention includes a plurality of battery cells 40 and a plurality of module BMS 300. The plurality of module BMS 300 are connected to and manage the plurality of battery cells 40 in a predetermined number, and send battery status information measured during the management process to the main BMS 100. For example, the battery module 200 may include 48 battery cells 40, such as Figure 3 As shown, when three BMS300 modules are set, each BMS300 module is connected to 16 cells to monitor the battery status of the 16 cells and generate battery status information based on the battery status to provide to the main BMS100.

[0048] The module BMS 300 according to the present invention includes an EIS measurement unit 310 for measuring the impedance of the cell 40 based on electrochemical impedance spectroscopy (EIS).

[0049] The EIS measurement unit 310 supplies AC signals with multiple frequencies (hereinafter referred to as "impedance measurement frequencies") to the cell 40 and uses the current and voltage measured therefrom to measure the impedance Z.

[0050] The EIS measurement unit 310 according to the present invention has a fast diagnostic function that measures the impedance of the cell 40 by one of the plurality of impedance measurement frequencies (hereinafter referred to as the "fast diagnostic mode frequency"), so as to perform fast impedance measurement in fast diagnostic mode.

[0051] The module BMS 300, equipped with the EIS measurement unit 310, receives a fast diagnostic mode setting request information from the main BMS 100. That is, under the control of the main BMS 100, the fast diagnostic mode is set, and the EIS measurement unit 310 is operated in the fast diagnostic mode to measure the impedance of the cell 40.

[0052] The BMS 300 module sequentially measures the impedance of the connected and managed cells 40. For example... Figure 3 As shown, when the battery cells 40 are connected in series, the preferred order is the series connection order, but it can also be a preset order (set according to the order of the battery cell index, etc.). The fast diagnostic mode frequency of module BMS 300 is predefined. When a fast diagnostic mode setting request information is received from main BMS 100, it is set to fast diagnostic mode, thereby measuring the impedance of cell 40 only using the fast diagnostic mode frequency. The fast diagnostic mode frequency is one of several impedance measurement frequencies defined by EIS, preferably a relatively high frequency.

[0053] In another embodiment, module BMS 300 receives from main BMS 100 a fast diagnostic mode setting request message including fast diagnostic mode frequency information related to the fast diagnostic mode frequency, and sets the frequency of the fast diagnostic mode frequency information included in the fast diagnostic mode setting request message as the fast diagnostic mode frequency, so that after the fast diagnostic mode is set, the impedance of cell 40 is measured only using the fast diagnostic mode frequency.

[0054] In the rapid diagnostic mode, since the EIS measurement unit 310 uses only one impedance measurement frequency (= rapid diagnostic mode frequency) to measure the impedance of a single cell instead of using multiple impedance measurement frequencies, the impedance of the cell can be measured quickly to detect thermal runaway in advance.

[0055] The main BMS 100 monitors for the occurrence of thermal runaway diagnostic events. When a thermal runaway diagnostic event occurs, the control module BMS 300 is set to a fast diagnostic mode. In the fast diagnostic mode, the impedance of the cell 40 of the battery module 200 is measured at the frequency of the fast diagnostic mode. When the measured impedance exceeds the reference value and the amount of impedance change exceeds the reference change, thermal runaway is predicted to occur in the battery module including the cell 40 and an alarm is issued.

[0056] When the administrator requests or the battery is fully charged, the main BMS 100 determines that a thermal runaway diagnostic event has occurred.

[0057] The impedance of the battery (cell), measured by multiple impedance measurement frequencies of the EIS measurement unit 310, forms before reaching the thermal runaway occurrence time point 421, as follows: Figure 4 The curve shown is in blue.

[0058] Therefore, when the impedance measured at the thermal runaway sensing start time 411 exceeds the reference value 412, the main BMS 100 determines it to be an abnormal range, thereby specifying the number of repeated measurements for the cell in the abnormal range, and after changing the measurement period setting, performing the impedance measurement of the cell for the number of repeated measurements with the period, and checking whether the amount of impedance change in the abnormal range, that is, in the abnormal state, exceeds the reference change amount.

[0059] When the measured impedance change exceeds the reference change, the main BMS 100 determines that there is a possibility of thermal runaway and issues an alarm.

[0060] exist Figure 4 In the process, the main BMS 100 can predict the probability of thermal runaway occurring between the thermal runaway sensing start time 411, which is earlier than the thermal runaway occurrence time 421, and the thermal runaway sensing prediction time 413.

[0061] The rapid diagnostic mode is a mode that measures impedance using only one of the multiple impedance measurement frequencies (= rapid diagnostic mode frequency) used by the EIS measurement unit 310 in order to quickly predict the possibility of thermal runaway.

[0062] like Figure 5 As shown, even if impedance is measured using only any one of the multiple frequencies of the EIS, it can be displayed that... Figure 4 The waveform is similar to the impedance curve. That is, from Figure 5 It can be seen that the possibility of thermal runaway can be predicted by measuring impedance at just one frequency.

[0063] like Figure 5 As shown, the main BMS 100 uses only the real part of the measured impedance, which includes both real and imaginary parts, to predict the possibility of thermal runaway.

[0064] Figure 6 This is a flowchart illustrating a thermal runaway pre-sensing method using a BMS with EIS functionality according to the present invention.

[0065] The following is for reference Figure 6 The main BMS 100 determines whether a thermal runaway diagnostic event has occurred (S111). The thermal runaway diagnostic event can occur when an administrator issues a thermal runaway diagnostic request, or it can occur when a specific battery module 200 or the entire battery module 200 is fully charged.

[0066] When a thermal runaway diagnostic event occurs, the main BMS 100 sends a fast diagnostic mode setting request message to the module BMS 300, thereby setting the module BMS 300 to fast diagnostic mode and setting itself to fast diagnostic mode as well (S113).

[0067] When the quick diagnostic mode is set, the main BMS 100 uses the EIS measurement unit 310 of the module BMS 300 to simultaneously acquire the impedance of the cells 40 of each module BMS 300 in the same order (S115).

[0068] After obtaining the impedance of cell 40, the main BMS 100 determines whether the impedance is within the normal range (S117).

[0069] If within the normal range, the main BMS 100 obtains the impedance to the next cell 40 through the module BMS 300 to determine whether the impedance is within the normal range (S117).

[0070] As described above, when the impedance of cell 40 is within the normal range, the process is repeated until the last cell 40 of module BMS 300 to determine whether the impedance of cell 40 is within the normal range (S119).

[0071] Conversely, when an impedance exceeding the normal range is sensed in the normal range determination step, the main BMS100 specifies the number of repeated measurements for the cell and changes the measurement cycle setting, thereby controlling the module BMS300 to repeatedly perform the specified number of impedance measurements with the changed measurement cycle (S121).

[0072] After specifying the number of repeated measurements and changing the measurement cycle, the main BMS 100 measures the impedance of the battery cell through the EIS measurement unit 310 of the module BMS 300 according to the changed measurement cycle (S123).

[0073] When impedance is measured, the main BMS 100 determines whether the impedance is within the normal range that does not exceed the reference value (S125).

[0074] If the threshold of the same measurement as before is not within the normal range, the main BMS 100 increases the number of repeated measurements (S131), classifies the deviation level according to the change in impedance between the previous and the current impedance, and determines whether the deviation level is above the preset level, that is, whether the change in impedance exceeds the preset reference change, thereby determining whether there is a possibility of thermal runaway (S135).

[0075] Then, as the number of repeated measurements increases (S131), the main BMS 100 again specifies the number of repeated measurements for the cell (S121) and measures the impedance of the cell (S123) to repeatedly determine whether the impedance is within the normal range (S125) and whether the possibility of thermal runaway is confirmed (S135).

[0076] At this point, if the possibility of thermal runaway is confirmed, the main BMS 100 issues an alarm. The alarm may include issuing a warning sound, a warning LED, flashing warning lights, displaying warning information on a monitor, or sending one or more warning messages to the management center, including information from the main BMS, module battery 200, and module BMS 300.

[0077] However, when the impedance measured in the step of determining whether the impedance is within the normal range (S125) returns to the normal range, the main BMS 100 reduces the number of repeated measurements (S127) and determines whether the reduced number of repeated measurements is zero (0) (S129).

[0078] If the number of repeated measurements is not zero, then in step S121 above, the number of repeated measurements is reduced, and after specifying the number of repeated measurements for the cell again, the measurement impedance of the cell is repeatedly determined to be within the normal range.

[0079] In this way, for cells whose initial measured impedance exceeds the normal range, the possibility of thermal runaway can be accurately determined, and erroneous judgments of the possibility of thermal runaway can be prevented.

[0080] On the other hand, the present invention is not limited to the above-described typical preferred embodiments. Those skilled in the art should readily understand that various modifications, alterations, substitutions, or additions can be made to implement the invention without departing from its spirit. If such modifications, alterations, substitutions, or additions fall within the scope of the claims of the present invention, then their technical concept should also be considered to be part of the present invention.

[0081] Explanation of reference numerals in the attached figures: 40: Cell 100: Main BMS 200: Battery module; 300: Module BMS 310: EIS Measurement Department

Claims

1. A thermal runaway pre-sensing device utilizing a BMS with EIS function, characterized in that, include: A battery module includes multiple battery cells and multiple module BMSs, wherein the multiple module BMSs are connected to a predetermined number of battery cells, and include an EIS measurement unit that uses an EIS with multiple frequencies to measure the impedance of the connected battery cells to monitor the impedance of the battery cells, and sets the battery cells to a fast diagnostic mode when a fast diagnostic mode is requested, thereby measuring the impedance of the battery cells using one of the frequencies of the EIS, namely the fast diagnostic mode frequency. as well as The main BMS monitors the occurrence of thermal runaway diagnostic events and, when such events occur, controls the module BMS to be set to a rapid diagnostic mode. In rapid diagnostic mode, the impedance of the battery module's cells is measured at the rapid diagnostic mode frequency. When the measured impedance exceeds a reference value and the change in impedance exceeds the reference change, thermal runaway is predicted to occur in the battery module containing the cells, and an alarm is issued.

2. The thermal runaway pre-sensing device using a BMS with EIS function according to claim 1, characterized in that, The battery module's BMS defines a fast diagnostic mode frequency and sets it to the fast diagnostic mode when it receives a fast diagnostic mode setting request from the main BMS.

3. The thermal runaway pre-sensing device using a BMS with EIS function according to claim 1, characterized in that, The main BMS defines the rapid diagnostic mode frequency and, when a thermal runaway diagnostic event occurs, sends a rapid diagnostic mode setting request message, including rapid diagnostic mode frequency information, to the module BMS to request the setting of the rapid diagnostic mode. When a quick diagnostic mode setting request is received due to the quick diagnostic mode setting request information, the BMS module defines the frequency of the quick diagnostic mode frequency information included in the quick diagnostic mode setting request information as the quick diagnostic mode frequency, so as to set the quick diagnostic mode.

4. The thermal runaway pre-sensing device using a BMS with EIS function according to claim 3, characterized in that, When the battery module is fully charged, the main BMS determines that the thermal runaway diagnostic event has occurred.

5. The thermal runaway pre-sensing device using a BMS with EIS function according to claim 1, characterized in that, The main BMS simultaneously measures the impedance of the same sequence of cells connected to each of the module BMS for a predetermined number of cells.

6. The thermal runaway pre-sensing device using a BMS with EIS function according to claim 5, characterized in that, When the impedance measured in a specific battery cell exceeds a reference value and is deemed abnormal, the main BMS sets the number of repeated measurements and the cycle for that battery cell. Within the number of repeated measurements, the impedance of the cell is repeatedly measured at the specified period, thereby predicting thermal runaway when the change in impedance exceeds a reference change.

7. The thermal runaway pre-sensing device using a BMS with EIS function according to claim 6, characterized in that, After determining that the battery cell is abnormal, when the measured impedance is less than or equal to the reference value, the main BMS reduces the number of repeated measurements, and sets the state to normal when the impedance is repeatedly measured to be less than or equal to the reference value, causing the number of repeated measurements to become zero.

8. A method for pre-sensing thermal runaway using a BMS with EIS function, characterized in that, include: The rapid diagnostic mode setting procedure is as follows: when a thermal runaway diagnostic event occurs, the main BMS control module BMS is set to rapid diagnostic mode. The impedance measurement step involves the module BMS measuring the impedance of the battery cell using EIS and measuring the impedance of the battery cell at a frequency of the fast diagnostic mode, i.e., the fast diagnostic mode frequency, to provide the impedance to the main BMS. The module BMS connects a predetermined number of battery cells from the plurality of battery cells and includes an EIS measurement unit that uses EIS to measure the impedance of the connected battery cells using multiple frequencies. as well as In the thermal runaway monitoring step, the main BMS measures the impedance of the battery module's cells at the frequency of the rapid diagnostic mode in rapid diagnostic mode. When the measured impedance exceeds a reference value and the amount of impedance change exceeds the reference change, it predicts that thermal runaway will occur in the battery module including the cells and issues an alarm.

9. The thermal runaway pre-sensing method using a BMS with EIS function according to claim 8, characterized in that, The steps for setting up the rapid diagnostic mode include: The rapid diagnostic mode setting request step involves the main BMS sending a rapid diagnostic mode setting request message to the module BMS when a thermal runaway diagnostic event occurs; and... The quick diagnostic mode setting step involves the module BMS receiving a quick diagnostic mode setting request from the main BMS, and setting a preset frequency among multiple frequencies of EIS as the quick diagnostic mode frequency to set the quick diagnostic mode.

10. The thermal runaway pre-sensing method using a BMS with EIS function according to claim 8, characterized in that, The steps for setting up the rapid diagnostic mode include: The rapid diagnostic mode setting request step involves the main BMS sending a rapid diagnostic mode setting request message, including rapid diagnostic mode frequency information, to the module BMS when a thermal runaway diagnostic event occurs, requesting the setting of the rapid diagnostic mode; and In the rapid diagnostic mode setting step, when the module BMS receives a rapid diagnostic mode setting request information from the main BMS, it sets the frequency of the rapid diagnostic mode frequency information in the rapid diagnostic mode setting request information to the rapid diagnostic mode frequency of the EIS measurement unit to set the rapid diagnostic mode.

11. The method for pre-sensing thermal runaway using a BMS with EIS function according to claim 9 or 10, characterized in that, The rapid diagnostic mode setting steps further include: The thermal runaway diagnostic event monitoring step involves the main BMS monitoring whether the battery module is fully charged. When the battery module is fully charged, it is determined that a thermal runaway diagnostic event has occurred. In the thermal runaway diagnostic event monitoring step, when a thermal runaway diagnostic event occurs, the main BMS executes the rapid diagnostic mode setting request step.

12. The thermal runaway pre-sensing method using a BMS with EIS function according to claim 11, characterized in that, In the impedance measurement step, for a predetermined number of connected cells, the module BMS is controlled synchronously with the main BMS, and measures the impedance of cells in the same order as other module BMS according to a predetermined sequence, and sends the results to the main BMS.

13. The thermal runaway pre-sensing method using a BMS with EIS function according to claim 12, characterized in that, The module BMS determines the impedance measurement sequence based on the series connection order of the battery cells connected to the module BMS.

14. The thermal runaway pre-sensing method using a BMS with EIS function according to claim 8, characterized in that, The thermal runaway monitoring steps include: In the centralized monitoring setting steps, under the rapid diagnostic mode, when the impedance measured in a specific battery cell exceeds a reference value and is determined to be abnormal, the main BMS sets the number of repeated measurements and the cycle for that battery cell; and In the thermal runaway prediction step, within the number of repeated measurements, the main BMS repeatedly measures the impedance of the cell at the specified cycle, thereby predicting that thermal runaway will occur when the change in impedance exceeds a reference change.

15. The thermal runaway pre-sensing method using a BMS with EIS function according to claim 14, characterized in that, The thermal runaway monitoring steps further include: In the thermal runaway error prevention step, after determining that the cell is abnormal, when the measured impedance is less than or equal to the reference value, the main BMS reduces the number of repeated measurements, and sets the state to normal when the impedance is repeatedly measured to be less than or equal to the reference value, causing the number of repeated measurements to become zero.

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