Battery management system for increasing battery power efficiency, and method therefor

Abstract

The present invention relates to a battery management system for increasing battery power efficiency, and a method therefor, which are capable of preventing a reduction in energy efficiency of a battery capacity due to thermal loss occurring in an alternating-current electrochemical impedance spectroscopy (EIS) measurement operation. The battery management system comprises: an EIS measurement path through which an EIS current flows by connecting positive (+) and negative (-) terminals of a battery pack; an EIS measurement unit formed on the EIS measurement path so as to measure the EIS of the battery pack on the basis of an EIS potential difference caused by the EIS current flowing through the EIS measurement path; a vibration energy harvesting unit for converting vibration energy into electrical energy; an energy storage unit for storing the electrical energy produced by the vibration energy harvesting unit; and a control unit which controls the EIS measurement unit and the vibration energy harvesting unit, and which controls that the vibration energy harvesting unit and the energy storage unit are connected so that the vibration energy is transmitted to the vibration energy harvesting unit.

Description

Battery management system and method for increasing battery power efficiency

[0001] The present invention relates to a battery management system, and more specifically, to a battery management system and a method thereof that can prevent a decrease in the energy efficiency of a battery capacity due to heat loss occurring during the measurement operation of Electrochemical Impedance Spectroscopy (EIS).

[0002] Recently, active research and development on rechargeable batteries has been underway. Rechargeable batteries are rechargeable batteries that encompass conventional Ni / Cd and Ni / MH batteries, as well as the more recent lithium-ion batteries. Among these, lithium-ion batteries have the advantage of significantly higher energy density compared to conventional Ni / Cd and Ni / MH batteries. Lithium-ion batteries can be manufactured in a compact and lightweight manner, making them widely used as power sources for mobile devices. Recently, their scope of application has expanded to include electric vehicles, drawing attention as a next-generation energy storage medium.

[0003] Electrochemical Impedance Spectroscopy (EIS) is an electrochemical technique that measures impedance curves for multiple alternating current frequencies. EIS is a technique that extracts equivalent circuit parameters of a battery based on impedance values ​​measured after applying an alternating current power source at different frequencies to the battery. EIS is used to estimate the lifespan or condition of a battery.

[0004] As such, EIS is a battery inspection method that verifies cell lifespan and charge capacity by analyzing changes in the sum of components (impedance) when alternating current or voltage is applied, thereby minimizing errors that occur during secondary battery connections. Furthermore, using EIS technology not only drastically reduces inspection time but also significantly lowers inspection costs, offering the advantage of inspecting secondary battery performance while ensuring both productivity and economic efficiency.

[0005] FIG. 1 is a drawing showing an EIS measuring device of a battery pack according to the prior art.

[0006] As illustrated in FIG. 1, an EIS measuring device for a battery pack according to the prior art comprises a battery pack (10) and an EIS measuring resistor (R) connected on the paths at both ends of the battery pack (10) through which current flows from the battery pack (10). EIS ) and a resistor (R) for EIS measurement on a first path connecting the (-) electrode of the battery pack (10). EIS An EIS switch (SW) connected in series with ) and controlling the frequency of the EIS AC current by turning the first path on / off. EIS It is composed of an EIS measuring unit (20) including ). At this time, the EIS measuring unit (20) is provided within a Battery Management System (BMS), and based on a control signal transmitted from the BMS, an EIS switch (SW EIS ) can be controlled.

[0007] However, a BMS board equipped with an EIS measurement device in a battery pack configured in this manner sends AC current from the BMS board to the battery pack or battery cells for EIS measurement. The amplitude of the EIS current flowing at this time is typically in amperes (A), and a significant amount of heat is generated due to the ampere-level EIS current when the EIS measurement function is operating.

[0008] EIS measurement resistor (R) during EIS measurement EISHeat loss occurs in ), and the heat loss occurring at this time is It is as large as that. Also, since EIS current is AC current, in order to generate AC current, the EIS switch (SW) must be matched to the intended EIS AC frequency. EIS It controls the on / off state of the ). As a result, the EIS switch (SW EIS Switching losses (=heat losses) also occur in ).

[0009] Such heat loss creates a limit that lowers the energy efficiency of the battery capacity every time EIS is measured.

[0010] Meanwhile, vibration energy (kinetic energy) generated in a vehicle containing a battery is also energy loss, and in conventional technology, the lost vibration energy is wasted as excess. At this time, the vibration energy may be vibration generated while the motor is operating or while the vehicle is in motion.

[0011] Prior art documents include (Patent Document 1) Korean Registered Patent Publication No. 10-1391501 (registered on April 25, 2014) and (Patent Document 2) Korean Published Patent Publication No. 10-2017-0135042 (published on December 8, 2017).

[0012] The present invention aims to provide a battery management system and a method for increasing battery power efficiency that can prevent a decrease in the energy efficiency of battery capacity due to heat loss occurring during the measurement operation of Electrochemical Impedance Spectroscopy (EIS).

[0013] The present invention aims to provide a battery management system and a method for increasing battery power efficiency, which can increase vehicle battery efficiency by converting wasted vibration energy generated during vehicle operation into usable electrical energy.

[0014] In particular, the present invention relates to a battery management system and a method thereof that can increase the energy efficiency of battery capacity by converting heat loss generated during specific EIS operations or vibrations generated during vehicle operation into electrical energy through an energy harvesting circuit included within the BMS.

[0015] A battery management system for increasing battery power efficiency according to an embodiment of the present invention comprises: a battery management system for measuring EIS of a battery pack, wherein the (+) and (-) terminals of the battery pack are connected to form an EIS measurement path through which an EIS current flows; an EIS measurement unit formed in the EIS measurement path and measuring the EIS of the battery pack based on an EIS potential difference caused by the EIS current flowing in the EIS measurement path; a vibration energy harvesting unit that converts vibration energy into electrical energy; an energy storage unit that stores electrical energy produced by the vibration energy harvesting unit; and a control unit that controls the EIS measurement unit and the vibration energy harvesting unit, and controls the vibration energy harvesting unit and the energy storage unit to be connected so that the vibration energy is transferred to the vibration energy harvesting unit.

[0016] The EIS measuring unit above applies an EIS current to the battery pack within a frequency range of a preset measurement frequency to measure the impedance of any battery cell.

[0017] The above EIS measuring unit is formed in the EIS measuring path and generates an EIS measuring resistor (R) that generates an EIS potential difference due to the EIS current flowing in the EIS measuring path. EIS ); and an EIS current switch (SW) formed in the EIS measurement path (L) and turning the EIS measurement path (L) on / off at a predetermined period. EIS ...including ), and the control unit comprises the EIS switch (SW EIS Controls the on / off of ) and calculates the EIS of the battery pack.

[0018] The vibration energy harvesting unit comprises: a piezoelectric unit that generates electrical energy by converting vibration energy generated during vehicle operation or vibration energy generated while a motor is operating; and a second DC-DC converter that steps up or steps down the output voltage of the piezoelectric unit to a predetermined voltage level.

[0019] The above vibration energy is characterized as being vibration energy generated in the BMS board by vibrations occurring during vehicle operation or vibrations occurring while the motor is operating.

[0020] The above piezoelectric part is characterized as being a piezoelectric device (PIEZO) that generates electrical energy from vibrational energy.

[0021] The energy storage unit stores electrical energy generated from the piezoelectric unit, which is stepped up or stepped down by the second DC-DC converter of the vibration energy harvesting unit.

[0022] The above energy storage unit is characterized by being a capacitor having a predetermined capacity.

[0023] The energy storage unit uses the stored electrical energy to charge the battery pack or as power to operate other functions within the battery management system (BMS).

[0024] The energy storage unit includes a connection path for connecting the battery pack, a charging switch for opening and closing the connection path, and a control unit for controlling the charging switch.

[0025] The battery management system further includes a thermal energy harvesting unit that converts thermal energy generated from the EIS measuring unit into electrical energy through an EIS measurement operation, the energy storage unit stores the electrical energy produced by the thermal energy harvesting unit, and the control unit controls the vibration energy harvesting unit and the energy storage unit to be connected so that the EIS measurement resistor (REIS ) and the EIS switch (SW EIS The thermal energy generated in ) is transferred to the thermal energy harvesting unit.

[0026] The thermal energy harvesting unit comprises: a thermoelectric generator (TEG) that generates electrical energy by converting thermal energy generated from the EIS measuring unit into electrical energy; and a first DC-DC converter that steps up or steps down the output voltage of the TEG to a predetermined voltage level.

[0027] The above TEG is the above EIS measurement resistance (R EIS ) and EIS current switch (SW EIS It is placed in direct contact with ) or in contact through a heat-conducting paste, etc.

[0028] The above TEG is characterized as being a thermoelectric element that generates electrical energy from the temperature difference between the high-temperature side and the low-temperature side.

[0029] The energy storage unit stores electrical energy generated from the TEG, which is stepped up or stepped down by the second DC-DC converter of the vibration energy harvesting unit.

[0030] A battery management method for increasing battery power efficiency according to an embodiment of the present invention is a battery management method using a battery management system for increasing battery power efficiency according to an embodiment of the present invention, wherein in a control unit, an EIS switch (SW EIS An EIS measurement operation control step that performs EIS measurement operation control by controlling ) to be turned on; and, while the EIS measurement operation is performed, the EIS measurement resistor (R EIS ) and the EIS switch (SW EISWhen thermal energy is generated in the thermal energy harvesting unit, the thermal energy generated is converted into electrical energy in a thermal-electric energy conversion step; when vibration energy is generated while driving a vehicle or while a motor is operating, the vibration energy generated is converted into electrical energy in a vibration energy harvesting unit; when vibration energy is generated, the vibration energy generated is converted into electrical energy in a vibration energy harvesting unit, the vibration energy generated is converted into electrical energy in a thermal-electric energy storage step; and when the electrical energy converted in the thermal energy harvesting unit is stored in an energy storage unit, the vibration-electric energy storage step is included.

[0031] The above thermal-electric energy storage step includes: a step in which the TEG converts thermal energy into electrical energy when heat rises around the TEG due to an EIS measurement operation; a step of stepping up or down the output voltage of the TEG to a desired voltage level using a first DC-DC converter; and a step of connecting the output of the first DC-DC converter to an energy storage unit to store electrical energy harvested from thermal energy.

[0032] The above vibration-electric energy storage step comprises: a step of generating electrical energy by the pressure effect by applying force (pressure) to a piezoelectric part through vibrations generated while driving a vehicle or vibrations generated while operating a motor; a step of stepping up or down the output voltage of the piezoelectric part to a desired voltage level using a second DC-DC converter; and a step of connecting the output of the second DC-DC converter to an energy storage unit to store electrical energy harvested from vibration energy.

[0033] The above EIS switch (SW EISThe method includes the step of controlling the battery pack to be turned off and controlling the charging operation of the battery pack using the electrical energy stored in the energy storage unit; and the step of controlling the battery pack so that when charging is not required, the electrical energy stored in the energy storage unit is used as power to operate other functions within the battery management system (BMS).

[0034] According to an embodiment of the present invention, the heat loss generated during a specific EIS operation is converted into electrical energy through an energy harvesting circuit included within the BMS, thereby achieving the effect of increasing the energy efficiency of the battery capacity. In other words, it is possible to prevent a decrease in the energy efficiency of the battery capacity caused by the heat loss generated during the EIS measurement operation.

[0035] In addition, vibrations generated during vehicle operation can be converted into electrical energy through a vibration energy harvesting circuit included within the BMS, thereby increasing the energy efficiency of the battery capacity. In other words, the energy efficiency of the battery capacity can be increased by utilizing the vibration energy generated during vehicle operation.

[0036] The features and advantages of the present invention can be better understood by referring to the following attached drawings together with the detailed description of embodiments of the present invention that follows, and among said drawings:

[0037] FIG. 1 is a drawing showing an EIS measuring device of a battery pack according to the prior art.

[0038] FIG. 2 is a diagram showing the configuration of a battery management system for increasing battery power efficiency according to an embodiment of the present invention.

[0039] FIG. 3 is a detailed diagram showing the configuration of the thermal energy harvesting unit of FIG. 2.

[0040] FIG. 4 is a detailed diagram showing the configuration of the vibration energy harvesting unit of FIG. 2.

[0041] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms, and the embodiments of the present invention are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. To explain the invention in detail, the drawings may be exaggerated, and like reference numerals in the drawings refer to like elements.

[0042] FIG. 2 is a diagram showing the configuration of a battery management system for increasing battery power efficiency according to an embodiment of the present invention. FIG. 3 is a diagram showing the configuration of the thermal energy harvesting unit of FIG. 2 in detail, and FIG. 4 is a diagram showing the configuration of the vibration energy harvesting unit of FIG. 2 in detail.

[0043] Referring to FIG. 2, a battery management system for increasing battery power efficiency according to an embodiment of the present invention comprises: an EIS measurement path (L) through which an EIS current (AC current for EIS measurement) flows by connecting the (+) and (-) terminals of a battery pack (100); an EIS measurement unit (200) formed in the EIS measurement path (L) and measuring the EIS of the battery pack based on the EIS potential difference caused by the EIS current flowing in the EIS measurement path (L); a thermal energy harvesting unit (300) that converts thermal energy generated from the EIS measurement unit (200) into electrical energy through an EIS measurement operation; a vibration energy harvesting unit (400) that converts vibration energy generated during vehicle operation or vibration energy generated while a motor operates into electrical energy; an energy storage unit (500) that stores the electrical energy converted from the thermal / vibration energy harvesting unit (300) (400); and the EIS measurement unit (200) and thermal / vibration energy It includes a control unit (600) that controls the harvesting unit (300) (400).

[0044] The battery pack (100) stores electrical energy supplied from a charger. The battery pack (100) includes a battery module configured by connecting at least one battery cell in series or in parallel.

[0045] The EIS measuring unit (200) applies an EIS current, which is an AC current for EIS measurement, to the battery pack (100) within a frequency range of a preset measurement frequency to measure the impedance of any battery cell.

[0046] For reference, the Battery Management System (BMS) of the battery pack records impedance data measured by the EIS measurement unit (200) according to a set measurement frequency and can visualize it by outputting it as a Nyquist or Bode plot. Through the output Nyquist or Bode plot, the BMS can analyze the change in impedance of the battery cell based on the measured impedance to evaluate the internal resistance, ion mobility, interface characteristics, etc. of the battery pack, and can interpret the electrochemical characteristics of the battery pack (10).

[0047] The EIS measuring section (200) is formed in the EIS measuring path (L) and generates an EIS measuring resistor (R) that creates an EIS potential difference due to the EIS current flowing in the EIS measuring path (L). EIS ) and an EIS current switch (SW) formed in the EIS measurement path (L) and turning the EIS measurement path (L) on / off at a predetermined period. EIS ) and, EIS switch (SW EIS It includes a control unit (600) that controls the on / off of ) and calculates the EIS of the battery pack.

[0048] EIS Current Switch (SW EIS ) is turned on / off at a predetermined period according to the control of the control unit (600) and the EIS measurement resistance (R EIS A frequency component that is the inverse of the above 'predetermined period' is applied to the voltage at both ends.

[0049] The thermal energy harvesting unit (300) performs an EIS measurement operation and the EIS measurement resistance (R EIS ) and EIS current switch (SW EIS It is a configuration that converts thermal energy generated from ) into electrical energy.

[0050] As illustrated in FIG. 3, it includes a thermoelectric generator (TEG) (310) that converts thermal energy generated in the EIS measuring unit (200) into electrical energy to generate electrical energy, and a first DC-DC converter (320) that increases or decreases the output voltage of the TEG (310) to a predetermined voltage level.

[0051] The TEG (310) includes a thermoelectric element that generates electrical energy from the temperature difference between the high-temperature side and the low-temperature side. At this time, the TEG (310) has an EIS measurement resistance (R EIS ) and EIS current switch (SW EIS It can be placed in direct contact with ) or in contact through a heat-conducting paste, etc.

[0052] When heat rises around the TEG (310) due to the EIS measurement operation, the thermal energy harvesting unit (300) converts the thermal energy into electrical energy. Then, a first DC-DC converter (320) is used to step up or step down the output voltage of the TEG (310) to a desired voltage level. The thermal energy harvesting unit (300) connects the output of the first DC-DC converter (320) to an energy storage unit (500) to store the electrical energy harvested from the thermal energy into electrical energy.

[0053] The vibration energy harvesting unit (400) is configured to convert vibration energy generated during vehicle operation into electrical energy.

[0054] As illustrated in FIG. 4, the system includes a piezoelectric unit (410) that generates electrical energy by converting vibration energy generated during vehicle operation or vibration energy generated while the motor is operating, and a second DC-DC converter (420) that increases or decreases the output voltage of the piezoelectric unit (410) to a predetermined voltage level. At this time, the vibration energy may utilize vibrations generated in the BMS board by vibrations generated during vehicle operation or vibrations generated while the motor is operating.

[0055] The piezoelectric unit (410) includes a piezoelectric device (PIEZO) that generates electrical energy from vibration energy. In this case, the piezoelectric unit (410) is mounted on the BMS board and generates electrical energy by utilizing vibration energy generated on the BMS board by vibrations occurring during vehicle operation or vibrations occurring while the motor is operating. In another embodiment, the piezoelectric unit (410) may be separately mounted in a part of the BMS where a lot of vibration occurs and may be wired connected to the second DC-DC converter (420). For example, in an electric vehicle, the case on which the battery pack is mounted is located at the bottom of the vehicle and may be directly subjected to road surface vibrations and shocks while driving, so the piezoelectric unit (410) can be attached to the case on which the battery pack is mounted. Additionally, the piezoelectric unit (410) can be attached to a point that is affected by the vibration of the entire vehicle, such as a mounting point that fixes the battery pack to the vehicle chassis.

[0056] The vibration energy harvesting unit (400) generates electrical energy through the piezoelectric effect by applying force (pressure) to the piezoelectric unit (410) through vibrations generated while driving a vehicle or vibrations generated while the motor is operating. A second DC-DC converter (420) is used to step up or step down the output voltage of the piezoelectric unit (410) to a desired voltage level. The vibration energy harvesting unit (400) connects the output of the second DC-DC converter (420) to an energy storage unit (500) to store the electrical energy harvested from vibration energy.

[0057] The energy storage unit (500) is configured to store electrical energy produced in the thermal / vibration energy harvesting unit (300) (400). That is, it stores electrical energy generated from a TEG (310) that is stepped up or stepped down by the first DC-DC converter (320) of the thermal energy harvesting unit (300), or stores electrical energy generated from a PEIZO (410) that is stepped up or stepped down by the second DC-DC converter (420) of the vibration energy harvesting unit (300). At this time, the energy storage unit (330) may include an element for storing electrical energy, for example, a capacitor having a predetermined capacity, or a supercapacitor having a much higher capacity than a general capacitor.

[0058] The electrical energy stored in the energy storage unit (330) may be used to charge the battery pack (100) or to be used as power to operate other functions within the battery management system (BMS). To this end, the battery management system (BMS) of the present invention may further include an auxiliary charging path (not shown) connecting the energy storage unit (500) and the battery pack (100), an auxiliary charging switch (not shown) for opening and closing the auxiliary charging path, and an auxiliary charging control unit for controlling the auxiliary charging switch. The auxiliary charging control unit may be configured separately or may control the auxiliary charging switch through the control of the control unit (600) below.

[0059] When the control unit (600) performs EIS measurement operation control, the EIS measurement resistor (R) during EIS measurement function operation EIS ) and EIS switch (SW EIS When heat generated in the heat / vibration energy harvesting unit (300) is transferred to the heat energy harvesting unit (300) and converted into electrical energy, the converted electrical energy is controlled to be stored in the energy storage unit (300). Additionally, the control unit (600) controls the vibration generated during vehicle driving or vibration generated while the motor is operating to be transferred to the vibration energy harvesting unit (400) and converted into electrical energy, so that the converted electrical energy is stored in the energy storage unit (300). For example, when electrical energy is generated in the heat / vibration energy harvesting unit (300) (400), the control unit (600) controls the connection of a separate electric charging switch (not shown) that opens and closes the electric energy charging path so that it can be connected to the energy storage unit (330), thereby allowing the electrical energy generated in the heat / vibration energy harvesting unit (300) (400) to be charged into the energy storage unit (330). Additionally, the control unit (600) controls the electric charging switch to be cut off when there is no generation of electric energy in the heat / vibration energy harvesting unit (300)(400), thereby disconnecting the connection between the heat / vibration energy harvesting unit (300)(400) and the energy storage unit (330), and preventing the discharge of electric energy stored in the energy storage unit (330).

[0060] The control unit may use the electrical energy stored in the energy storage unit (500) as power to operate other functions within the battery management system (BMS).

[0061] In this way, the battery management system of the present invention can achieve the effect of increasing battery energy efficiency by converting thermal energy generated in the EIS measuring unit (200) during a specific EIS operation and / or vibration energy generated while the vehicle is driving or while the motor is operating into electrical energy through the thermal / vibration energy harvesting unit (300)(400) included in the BMS.

[0062] Meanwhile, the control unit (600) controls the EIS switch (SW) based on a control signal transmitted from the MCU or BMIC of the BMS. EIS It is a means for controlling the on / off of ), or the MCU / BMIC is configured as a control unit (600), or an EIS switch (SW) is provided outside the BMS EIS It can be a means of controlling the on / off of ).

[0063]

[0064] Hereinafter, a battery management method for increasing battery power efficiency according to an embodiment of the present invention is described. The battery management method for increasing battery power efficiency according to an embodiment of the present invention may be a method for processing a received signal using the aforementioned battery management system, and since the aforementioned details regarding the battery management system may be applied as is, the description of redundant details may be omitted.

[0065] A battery management method for increasing battery power efficiency according to an embodiment of the present invention utilizes a battery management system comprising an EIS measurement path (L), an EIS measurement unit (200), a thermal energy harvesting unit (300), a vibration energy harvesting unit (400), an energy storage unit (500), and a control unit (600), as illustrated in FIG. 2, and comprises an EIS measurement operation control step, a thermal-electric energy conversion step, a vibration-electric energy conversion step, a thermal-electric energy storage step, and a vibration-electric energy storage step.

[0066] As a control step for the EIS measurement operation, through the control of the control unit (600), the EIS switch (SW EIS Control the EIS measurement operation by turning it on.

[0067] And as a thermal-electrical energy conversion step, while the EIS measurement operation is performed, the EIS measurement resistor (R EIS ) and the EIS switch (SW EISWhen thermal energy is generated in the ), the generated thermal energy is used to convert it into electrical energy in the thermal energy harvesting unit (300).

[0068] Additionally, as a vibration-electric energy conversion step, when vibration occurs during vehicle driving or when vibration energy is generated while the motor is operating, the generated vibration energy is converted into electrical energy in the vibration energy harvesting unit (400).

[0069] And as a thermal-electric energy storage step and a vibration-electric energy storage step, the thermal-electric energy converted in the thermal energy harvesting unit (300) and the vibration-electric energy converted in the vibration energy harvesting unit (400) are stored in the energy storage unit (500).

[0070] At this time, the thermal-electric energy storage, as explained with reference to FIG. 3, includes the step of converting thermal energy into electrical energy when heat rises around the TEG due to the EIS measurement operation, the step of using the first DC-DC converter (320) to increase or decrease the output voltage of the TEG (310) to a desired voltage level, and the step of connecting the output of the first DC-DC converter (320) to the energy storage unit (500) to store the thermal-electric energy harvested from thermal energy into electrical energy.

[0071] Additionally, vibration-electric energy storage, as described with reference to FIG. 4, includes the step of generating electric energy by the piezoelectric effect by applying force (pressure) to the piezoelectric part (410) by vibration generated while driving a vehicle or vibration generated while the motor is operating, the step of increasing or decreasing the output voltage of the piezoelectric part (410) to a desired voltage level using a second DC-DC converter (420), and the step of connecting the output of the second DC-DC converter (420) to an energy storage part (500) to store electric-electric energy in which vibration energy is energy harvested into electric energy.

[0072] Meanwhile, the electrical energy stored in the energy storage unit (500) can be used to charge the battery pack (100), or when charging of the battery pack (100) is not required, the electrical energy stored in the energy storage unit (500) can be used as power to operate other functions within the battery management system (BMS).

[0073]

[0074] In the foregoing, preferred embodiments of the present invention have been described and illustrated using specific terms, but such terms are intended solely to clarify the present invention, and it is obvious that various modifications and changes may be made to the embodiments and terms described in the present invention without departing from the technical spirit and scope of the following claims. Such modified embodiments should not be understood separately from the spirit and scope of the present invention, but should be considered to fall within the scope of the claims of the present invention.

[0075] Meanwhile, the names of the reference numerals used in the present invention are as follows.

[0076] 100: Battery pack, 200: EIS measurement unit, 300: Thermal energy harvesting unit, 310: TEG, 320: First DC-DC converter, 400: Vibration energy harvesting unit, 410: PEIZO, 420: Second DC-DC converter, 500: Energy storage unit, 600: Control unit

Claims

1. As a battery management system for measuring the EIS of a battery pack, An EIS measurement path through which EIS current flows by connecting the (+) and (-) terminals of the above battery pack; An EIS measuring unit formed in the above EIS measuring path, which measures the EIS of the battery pack based on the EIS potential difference caused by the EIS current flowing in the above EIS measuring path; Vibration energy harvesting unit that converts vibration energy into electrical energy; An energy storage unit that stores electrical energy produced in the above vibration energy harvesting unit; and A battery management system comprising a control unit that controls the above EIS measuring unit and the above vibration energy harvesting unit.

2. In Paragraph 1, The above EIS measuring unit is a battery management system that measures the impedance of any battery cell by applying an EIS current to the battery pack within a frequency range of a preset measurement frequency.

3. In Paragraph 1 or 2, The above EIS measuring unit is, An EIS measurement resistor (R) formed in the above EIS measurement path, generating an EIS potential difference due to the EIS current flowing in the above EIS measurement path. EIS ); and An EIS current switch (SW) formed in the above EIS measurement path (L) and turning the EIS measurement path (L) on / off at a predetermined period. EIS Includes ), The above control unit is the EIS switch (SW EIS A battery management system that controls the on / off of ) and calculates the EIS of the battery pack.

4. In Paragraph 1, The above vibration energy harvesting unit is, A piezoelectric element that generates electrical energy by converting vibration energy generated during vehicle operation or vibration energy generated while a motor is operating into electrical energy; and A battery management system comprising a second DC-DC converter that increases or decreases the output voltage of the above-mentioned piezoelectric part to a predetermined voltage level.

5. In Paragraph 1 or Paragraph 4, A battery management system characterized in that the above vibration energy is vibration energy generated in the BMS board by vibrations occurring during vehicle operation or vibrations occurring while the motor is operating.

6. In Paragraph 4, A battery management system characterized in that the above-mentioned piezoelectric part is a piezoelectric device (PIEZO) that generates electrical energy from vibration energy.

7. In Paragraph 4, The above energy storage unit is a battery management system that stores electrical energy generated from the piezoelectric unit, which is stepped up or stepped down by the second DC-DC converter of the vibration energy harvesting unit.

8. In Paragraph 1 or Paragraph 7, A battery management system characterized in that the energy storage unit is a capacitor having a predetermined capacity.

9. In Paragraph 1 or Paragraph 7, The above energy storage unit is a battery management system that uses the stored electrical energy to charge the battery pack or as power to operate other functions within the battery management system (BMS).

10. In Paragraph 9, The above energy storage unit is, A connection path for connecting the above battery pack, and A charging switch that opens and closes the above connection path, and A battery management system including a control unit that controls the above-mentioned charging switch.

11. In Paragraph 1, The above battery management system is, It further includes a thermal energy harvesting unit that converts thermal energy generated from the EIS measuring unit into electrical energy through an EIS measurement operation, The energy storage unit stores electrical energy produced by the thermal energy harvesting unit, and The above control unit controls the thermal energy harvesting unit and the energy storage unit to be connected, thereby controlling the EIS measurement resistor (R EIS ) and the EIS switch (SW EIS A battery management system that transfers thermal energy generated in the above-mentioned thermal energy harvesting unit.

12. In Paragraph 11, The above thermal energy harvesting unit is, A thermoelectric generator (TEG) that generates electrical energy by converting thermal energy generated in the above EIS measuring unit into electrical energy; and A battery management system comprising a first DC-DC converter that steps up or steps down the output voltage of the above TEG to a predetermined voltage level.

13. In Paragraph 12, The above TEG is the above EIS measurement resistance (R EIS ) and EIS current switch (SW EIS A battery management system that is placed in direct contact with ) or in contact through a thermal conductive paste, etc.

14. In Paragraph 12, A battery management system characterized in that the above TEG is a thermoelectric element that generates electrical energy from the temperature difference between the high-temperature side and the low-temperature side.

15. In Paragraph 12, The above energy storage unit is a battery management system that stores electrical energy generated from the TEG, which is stepped up or stepped down by the second DC-DC converter of the vibration energy harvesting unit.

16. A battery management method using a battery management system comprising any one of claims 1 to 15, wherein, in a control unit, EIS Switch (SW) EIS An EIS measurement operation control step that performs EIS measurement operation control by controlling ) to turn on; While the above EIS measurement operation is being performed, the EIS measurement resistor (R EIS ) and the EIS switch (SW EIS When thermal energy is generated in ), a thermal-to-electrical energy conversion step in which the thermal energy harvesting unit converts the generated thermal energy into electrical energy; A vibration-to-electric energy conversion step in which, when vibration occurs during vehicle driving or vibration energy is generated while a motor is operating, the vibration energy harvesting unit converts the generated vibration energy into electrical energy; A thermal-electric energy storage step for storing electrical energy converted in the above thermal energy harvesting unit in an energy storage unit; and A battery management method comprising a vibration-electric energy storage step in which electrical energy converted from the above vibration energy harvesting unit is stored in an energy storage unit.

17. In Paragraph 16, The above thermal-electric energy storage step is, When heat rises around the TEG due to the EIS measurement operation, the TEG converts thermal energy into electrical energy; A step of boosting or lowering the output voltage of the TEG to a desired voltage level using a first DC-DC converter; and A battery management method comprising the step of connecting the output of the first DC-DC converter to an energy storage unit to store electrical energy harvested from thermal energy into electrical energy.

18. In Paragraph 16, The above vibration-electric energy storage step is, A step of generating electrical energy by the piezoelectric effect by applying force (pressure) to the piezoelectric part through vibrations generated while driving a vehicle or vibrations generated while the motor is operating; A step of boosting or lowering the output voltage of the piezoelectric part to a desired voltage level using a second DC-DC converter; and A battery management method comprising the step of connecting the output of the second DC-DC converter to an energy storage unit to store electrical energy harvested from vibration energy into electrical energy.

19. In Paragraph 16, The above EIS switch (SW EIS A step of controlling ) to turn off and controlling the charging operation of the battery pack with the electrical energy stored in the energy storage unit; and A battery management method comprising the step of controlling the electrical energy stored in the energy storage unit to be used as power to operate other functions within the battery management system (BMS) when charging of the battery pack is not required.

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