Battery system, electric vehicle including the same, and method for operating an electric vehicle

Abstract

A battery system applied to an electric vehicle may include a battery pack including a plurality of battery cells, a battery management system that measures information about the battery pack and manages the battery pack based on the measured information, and a battery black box that supplies power to the battery management system in a start-stop state of the electric vehicle and stores battery pack management information generated by the battery management system. The battery pack management information may include information about at least one of a plurality of cell voltages of the plurality of battery cells, a current and a temperature of the battery pack, and an insulation resistance of the battery pack.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2021 - 0187700 filed on Dec. 24, 2021, and all contents disclosed in the document of the Korean Patent Application are incorporated herein by reference in their entirety.

[0002] The present disclosure relates to a battery system, an electric vehicle including the same, and a method of operating an electric vehicle.

Background Art

[0003] A BMS (Battery Management System) can monitor the voltage, current, temperature, etc. of a battery in real - time and estimate the battery state based on the measured information. The battery can provide power for driving an electric vehicle. The electric vehicle can include not only a vehicle in which the driving force of the vehicle is supplied only from a motor, but also a vehicle in which an internal combustion engine and a motor together provide the driving force of the vehicle.

[0004] When the ignition of an electric vehicle with a battery attached is turned off (ignition off), the BMS also enters a power - off state, similar to other electric field ECUs (Electronic Control Units) in the electric vehicle. Generally, a fire in an electric vehicle occurs in the vehicle, so when a fire occurs in an electric vehicle, it is impossible to analyze the battery state at the time when the fire occurs. The power supply is turned off When the ignition of an electric vehicle with a battery attached is turned off (ignition off), the BMS also enters a power - off state, similar to other electric field ECUs (Electronic Control Units) in the electric vehicle. Generally, a fire in an electric vehicle occurs in the vehicle, so when a fire occurs in an electric vehicle, it is impossible to analyze the battery state at the time when the fire occurs. The power supply is in the off state When the ignition of an electric vehicle with a battery attached is turned off (ignition off), the BMS also enters a power - off state, similar to other electric field ECUs (Electronic Control Units) in the electric vehicle. Generally, a fire in an electric vehicle occurs in the vehicle, so when a fire occurs in an electric vehicle, it is impossible to analyze the battery state at the time when the fire occurs.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Provide an apparatus and method capable of storing the battery state even after the ignition of an electric vehicle is turned off. The power supply has turned off Provide an apparatus and method capable of storing the battery state even after the ignition of an electric vehicle is turned off.

Means for Solving the Problems

[0006] A battery system applied to an electric vehicle according to one feature of the invention includes a battery pack including a plurality of battery cells, a battery management system that measures information regarding the battery pack and manages the battery pack based on the measured information, and the The power supply is in the off state of the electric vehicle may include a battery black box that supplies power to the battery management system and stores battery pack management information generated from the battery management system. The battery pack management information may include information regarding at least one of a plurality of cell voltages of the plurality of battery cells, a current and temperature of the battery pack, and an insulation resistance of the battery pack.

[0007] The battery black box may include a communication unit that receives the battery pack management information, a control unit that receives transmission of the battery pack management information from the communication unit and stores it in a memory, and the The power supply is in the off state of the electric vehicle may include a black box battery that supplies power to the battery management system.

[0008] The black box battery may be The power supply is in the on state charged by the electric vehicle.

[0009] The battery black box may be The power supply is in the off state of the electric vehicle, where an output voltage of the black box battery is supplied to the battery management system, and may further include a power switching unit that operates such that the black box battery is charged The power supply is in the on state of the electric vehicle.

[0010] The communication unit receives Power off or On instructing the Power state information from an electronic control circuit of the electric vehicle through CAN communication, and the control unit may control the power switching unit according to the Power state information .

[0011] The battery management system includes a first communication unit for transmitting the battery pack management information to the battery black box. The battery black box includes a second communication unit for receiving the battery pack management information. The first communication unit and the second communication unit can be connected by CAN communication.

[0012] An electric vehicle according to another feature of the present invention includes an auxiliary battery, a battery pack, a battery management system for managing the battery pack, and The power supply is in the off state a battery system including a battery black box for storing battery pack management information. The electric vehicle The power supply is in the on state may further include a switching unit for connecting the auxiliary battery and the battery management system, and The power supply is in the off state for connecting the battery black box and the battery management system.

[0013] The battery black box The power supply is in the off state includes a black box battery for supplying power to the battery management system. The battery pack management information may include information regarding at least one of a plurality of cell voltages of the plurality of battery cells, a current and temperature of the battery pack, and an insulation resistance of the battery pack.

[0014] The electric vehicle The power supply is in the on state may further include a DC-DC converter for charging the auxiliary battery and the black box battery.

[0015] The battery black box The power supply is in the off state may store battery pack management information generated from the battery management system.

[0016] The battery black box includes a communication unit for receiving the battery pack management information; and

[0017] It may further include a control unit that receives the transmission of the battery pack management information from the communication unit and stores it in the memory.

[0018] The battery black box is for the electric vehicle The power supply is in the off state wherein the output voltage of the black box battery is supplied to the battery management system, and for the electric vehicle The power supply is in the on state It may further include a power switching unit that operates so that the black box battery is charged.

[0019] The communication unit receives an instruction for the electric vehicle Power off or on from the electronic control circuit of the electric vehicle through CAN communication, and the control unit may control the power switching unit according to the Power state information received instruction. Power state information The electric vehicle may further include an electronic control circuit that senses the

[0020] of the electric vehicle Power on or Off and generates Power state information and transmits the Power state information to at least one of the battery management system and the battery black box.

[0021] The battery management system includes a first communication unit for transmitting the battery pack management information to the battery black box, the battery black box includes a second communication unit for receiving the battery pack management information, and the first communication unit and the second communication unit may be connected by CAN communication.

[0022] In a method of operating an electric vehicle according to another feature of the invention, the electric vehicle may receive power supply from a battery system including a battery management system that manages a battery pack including a plurality of battery cells. The method of operating the electric vehicle is for the electric vehicle including the battery system The power supply is onStages including the state, the stage where the battery black box supplies power to the battery management system, the stage where the battery management system acquires information regarding the battery pack and generates battery pack management information, and the stage where the battery black box stores the battery pack management information generated from the battery management system. The battery pack management information may include information regarding at least one of the plurality of cell voltages of the plurality of battery cells, the current and temperature of the battery pack, and the insulation resistance of the battery pack.

[0023] The method of operating the electric vehicle includes that of the electric vehicle The power supply is in the on state wherein the black box battery is charged, and that of the electric vehicle The power supply is in the on state may further include the stage where the auxiliary battery of the electric vehicle supplies power to the battery management system.

Advantages of the Invention

[0024] The present invention provides a battery system capable of storing the battery state even after the electric vehicle The power supply has turned off is used, an electric vehicle including the same, and a method of operating the electric vehicle.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Best Mode for Carrying Out the Invention

[0026] Hereinafter, the embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings. The same or similar components are given the same or similar reference numerals, and the overlapping descriptions thereof are omitted. The suffixes “module” and / or “unit” for the components used in the following description are given or mixed only for the ease of preparing the specification, and do not have meanings or roles that are distinguishable from each other by themselves. Further, when it is determined that the specific description of the related known technology obscures the gist of the embodiments disclosed in this specification in explaining the embodiments disclosed in this specification, the detailed description thereof is omitted. The accompanying drawings are for facilitating the understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the accompanying drawings, and should be understood to include all modifications, equivalents, or alternatives included in the idea and technical scope of the present invention.

[0027] Terms including ordinal numbers such as first, second, etc. can be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

[0028] In this application, terms such as “comprising” or “having” are for specifying the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0029] In the configuration that controls other configurations under specific control conditions among the configurations according to an embodiment, a program embodied as a set of instructions that embody the control algorithm necessary to control other configurations is installed. The control configuration processes input data and stored data by the installed program to generate output data. The control configuration can include a non-volatile memory that stores the program and a memory that stores data.

[0030] Hereinafter, with reference to the drawings, a battery system according to an embodiment and an electric vehicle including the same will be described. The electric vehicle includes a vehicle driven only by a motor without an internal combustion engine, a hybrid vehicle including both an internal combustion engine and a motor, and the like.

[0031] FIG. 1 is a diagram schematically showing an electric vehicle to which a battery system according to an embodiment is applied.

[0032] As shown in FIG. 1, the electric vehicle 1 includes a battery system 2, a power conversion device 40, an electronic control circuit (Electronic Control Unit, ECU, 50), a DC-DC converter 60, an auxiliary battery 70, a switching unit 80, and a CAN bus line 90.

[0033] The power conversion device 40 supplies the power supplied from the battery pack 10 by the discharge of the battery pack 10 to a motor (not shown) that provides driving force to the electric vehicle 1 or to other electrical loads other than the motor. At this time, the power conversion device 40 receives the input of the battery voltage VB of the battery pack 10, and the current of the battery pack 10 (hereinafter, battery pack current, IB) flows into the power conversion device 40. In addition, the power conversion device 40 can supply the power supplied from an alternator (not shown) or the power supplied from an external commercial power source to the battery pack 10 to charge the battery pack 10.

[0034] The operation of the power conversion device 40 is controlled by the ECU 50. The control command of the ECU 50 is transmitted to the power conversion device 40 via the CAN bus line 90. The ECU 50 requests information necessary for control from the power conversion device 40 and receives it from the power conversion device 40.

[0035] The ECU 50 acquires information necessary for controlling the electric vehicle 1, generates a control command based on the acquired information, and transmits the control command to the corresponding component via the CAN bus line 90.

[0036] For example, the ECU 50 senses the Power on of the electric vehicle 1 and transmits the sensing to at least one of the battery management system (Battery Management System, BMS, 20) and the BMS black box 30, and can control the switching unit 80 so that the power supply voltage VCC is supplied from the auxiliary battery 70 to the BMS 20. Also, the ECU 50 senses the Power on of the electric vehicle 1, transmits the sensing to at least one of the BMS 20 and the BMS black box 30, and can control the switching unit 80 so that the power supply voltage VCC is supplied from the BMS black box 30 to the BMS 20. At this time, the ECU 50 can generate a switching control signal PSW for controlling the operation of the switching unit 80. Power off of the electric vehicle 1, transmits the sensing to at least one of the BMS 20 and the BMS black box 30, and can control the switching unit 80 so that the power supply voltage VCC is supplied from the BMS black box 30 to the BMS 20. At this time, the ECU 50 can generate a switching control signal PSW for controlling the operation of the switching unit 80. Power off When the ECU 50 senses the

[0037] also, when the ECU 50 senses the Power on , it can close the relay 5 to control the auxiliary battery 70 to be charged by the DC-DC converter 60. When the ECU 50 senses the Power off , it can open the relay 5 to cut off the connection between the DC-DC converter 60 and the auxiliary battery 70. At this time, the ECU 50 can generate a relay control signal RS for controlling the relay 5 .

[0038] The DC-DC converter 60 supplies power for charging the auxiliary battery 70 and the BMS black box 30 using the input voltage Vin. The output voltage of the power supplied from the DC-DC converter 60 can be at a level suitable for charging the auxiliary battery 70 and the BMS black box 30. The input voltage Vin of the DC-DC converter 60 can be a commercial power source such as a wall power supply or supplied from the battery system 2.

[0039] Relay 5 is connected between the output terminal DOUT of the DC-DC converter 60 and the contact point N1, and opens and closes according to the relay control signal RS. The contact point N1 is connected to the charging terminal AB2 connected to the positive electrode of the auxiliary battery 70 and the charging terminal BB2 of the battery black box 30. Therefore, when the relay 5 is closed, the auxiliary battery 70 and the battery black box 30 can be charged by the power supplied from the DC-DC converter 60.

[0040] The auxiliary battery 70 supplies power to the electrical equipment loads (not shown) of the electric vehicle 1. The loads can include all types of electrical equipment loads through which current flows and power is consumed, such as various types of electronic control devices, speed sensors, switches, speakers, lamps, etc. that control the operation of the electric vehicle 1. The output voltage AOUT can be supplied to the electrical equipment loads and the switching unit 80 through the output terminal AB1 of the auxiliary battery 70.

[0041] The switching unit 80 connects one of the auxiliary battery 70 and the battery black box 30 to the BMS20 according to the switching control signal PSW. When the BMS20 is connected to the auxiliary battery 70, the output voltage 1 of the auxiliary battery 70 can be supplied as the power supply voltage VCC of the BMS20 to the power supply terminal PW of the BMS20. When the BMS20 is connected to the battery black box 30, the output voltage 2 supplied through the output terminal BB1 of the battery black box 30 can be supplied as the power supply voltage VCC of the BMS20 to the power supply terminal PW of the BMS20.

[0042] The battery system 1 includes a battery pack 10, a BMS 20, a battery black box 30, and first and second contacts 101, 102.

[0043] The first contact 101 is connected between the positive electrode P+ of the battery pack 10 and the power conversion device 40 and is switched under the control of the BMS 20. The second contact 102 is connected between the negative electrode P− of the battery pack 10 and the power conversion device 40 and is switched under the control of the BMS 20. The BMS 20 may generate switching signals SC1, SC2 for controlling the switching operations of the first and second contacts 101, 102 and supply them to the first and second contacts 101, 102.

[0044] The battery pack 10 includes a plurality of battery cells (10_1 to 10_n, where n is a natural number of 2 or more) connected in series.

[0045] The BMS 20 is connected to both ends of each of the plurality of battery cells (10_1 to 10_n). The BMS 20 measures the cell voltage of each of the plurality of battery cells (10_1 to 10_n), measures the current of the battery pack 10 (hereinafter, the battery pack current) and the temperature (hereinafter, the battery pack temperature), and may control and perform cell balancing for the plurality of battery cells (10_1 to 10_n).

[0046] The BMS 20 estimates the SOC (State of Charge), SOH (State of Health), SOP (State of Power), etc. of the battery pack 10 based on the plurality of cell voltages of the plurality of battery cells (10_1 to 10_n) and the information related to the measured battery pack 10. The BMS 20 can control charging and discharging based on the information related to the electric vehicle 1 obtained from the ECU 50 and the estimated state of the battery pack 10.

[0047] In addition, the BMS 20 can measure the insulation resistance with respect to the battery pack 10. The insulation resistance with respect to the battery pack 10 is a resistance indicating the insulation state between the battery pack 10 and the ground. Various insulation measurement methods are known, and the BMS 20 according to one embodiment can use one of the known insulation measurement methods.

[0048] The battery black box 30 is of the electric vehicle 1 The power supply has turned off Subsequently, a power supply voltage is supplied to the BMS 20, and information related to a plurality of cell voltages, battery pack current, and battery pack temperature received from the BMS 20 is stored.

[0049] FIG. 2 is a diagram schematically showing the inside of a battery system according to one embodiment.

[0050] As shown in FIG. 2, the BMS 20 includes a monitoring circuit 21, an MCU 22, a communication unit 23, and a power supply unit 24. Inside the battery pack 10, a current sensor 25 for measuring the battery pack current and a temperature sensor 26 for measuring the battery pack temperature are located.

[0051] The current sensor 25 measures the battery pack current and transmits information related to the measured battery pack current to the MCU 22. In FIG. 2, the case where the current sensor 25 is located between the battery cell 10_1 and the positive terminal P+ is shown, but the current sensor 25 can be located at any point in the path of the battery pack current. The current sensor 25 can be embodied as a hall sensor and can transmit a voltage signal (hereinafter, current sensing signal, IS) due to the magnetic field by the battery pack current to the MCU 22.

[0052] The temperature sensor 26 measures the battery pack temperature and transmits information related to the battery pack temperature to the MCU 22. In FIG. 2, a case where one temperature sensor 26 is connected between the battery cell 10_n and the negative terminal P- is shown, but two or more temperature sensors may be located between other cells of the battery pack 10. The temperature sensor 26 can be realized as a thermistor, and the voltage across both ends of the temperature sensor 26 (hereinafter, temperature sensing signal, TS) can be transmitted to the MCU 22.

[0053] The monitoring circuit 21 measures the voltage difference between the positive and negative electrodes of each of the plurality of battery cells (10_1 to 10_n), and generates a battery cell voltage VSi based on the measured voltage difference. The monitoring circuit 21 transmits the plurality of cell voltages (VC1 to VCn) of the plurality of battery cells (10_1 to 10_n) to the MCU 22. The monitoring circuit 21 can discharge the balancing target cell among the plurality of battery cells (10_1 to 10_n) based on the cell balancing control signal BS transmitted from the MCU 22.

[0054] The MCU 22 acquires information related to the battery pack current based on the current sensing signal, the battery pack temperature based on the temperature sensing signal, and the plurality of cell voltages (VC1 to VCn), controls the charging and discharging of the battery pack 10, generates a cell balancing control signal BS for controlling the cell balancing operation for the plurality of battery cells (10_1 to 10_n), and diagnoses an abnormality that may occur in the battery pack 10. The MCU 22 can turn on the first and second contacts 101 and 102 for charging the battery pack 10 and discharging from the battery pack 10. When the first and second contacts 101 and 102 are in the on state, the battery pack 10 can be charged or supply power to the power conversion device 40. The MCU 22 can generate switching signals SC1 and SC2 at a level to turn on the first and second contacts 101 and 102, or generate switching signals SC1 and SC2 at a level to turn off the first and second contacts 101 and 102.

[0055] The BMS20 monitors the battery pack 10 at regular intervals (hereinafter referred to as the monitoring period) in an electric vehicle. At each monitoring period, the monitoring circuit 21 generates a plurality of cell voltages (VC1~VCn) and transmits them to the MCU22. The current sensor 25 senses the battery pack current and transmits a current sensing signal IS to the MCU22. The temperature sensor 26 senses the battery pack temperature and transmits a temperature sensing signal TS to the MCU22. The MCU22 measures the insulation resistance. The power supply is in the off state

[0056] At each monitoring period, the MCU22 aggregates and processes information related to a plurality of cell voltages (VC1~VCn), the battery pack current, the battery pack temperature, and the insulation resistance to generate battery management information BMI and transmits it to the communication unit 23. The information generated at each monitoring period in the electric vehicle is referred to as battery management information BMI. The battery management information BMI can be implemented in the CAN data type. The power supply is in the off state

[0057] The BMS20 does not generate battery management information BMI in the [state of the electric vehicle]. The power supply has turned on In the [state of the electric vehicle], since the BMS20 processes the information necessary for the management of the battery pack, there is no need to transmit information externally. However, when there is a request for information related to the battery pack from an approved external device such as the ECU50, the BMS20 transmits the requested information to the communication unit 23. The power supply has turned on

[0058] The communication unit 23 transmits the information received from the CAN bus line 90 to the MCU22, or transmits information related to the battery pack or the battery management information BMI to the CAN bus line 90 in response to the control of the MCU22.

[0059] ​​​The power supply unit 24 converts the power supply voltage VCC to a level suitable for each component of the BMS 20 and supplies it. For example, the power supply unit 24 may convert the power supply voltage VCC to a voltage VS1 at a level suitable for the MCU 22 and supply it to the MCU 22. The power supply unit 24 converts the power supply voltage VCC to a voltage VS3 at a level suitable for the monitoring circuit 21 and Monitoring circuit 21 supplies it to. The power supply unit 24 may convert the power supply voltage VCC to a voltage VS2 at a level suitable for the communication unit 23 and supply it to the communication unit 23.

[0060] FIG. 3 is a diagram schematically showing a battery black box according to an embodiment.

[0061] As shown in FIG. 3, the battery black box 30 can include a control unit 31, a memory 32, a black box battery 33, a communication unit 34, and a power switching unit 35.

[0062] The communication unit 34 receives the battery management information BMI from the CAN bus line 90 and transmits the battery management information BMI to the control unit 31. The communication unit 34 can transmit the information transmitted from the control unit 31 to the CAN bus line 90 according to the control of the control unit 31.

[0063] When the control unit 31 receives the battery management information BMI, it stores it in the memory 32. In FIG. 3, the control unit 31 and the memory 32 are shown as separate configurations, but the control unit 31 can include the memory 32. The control unit 31 senses an abnormal event based on the battery management information BMI and records the information related to the sensed abnormal event in the memory 32. For example, when the control unit 31 analyzes the battery management information BMI and detects a rapid change in cell voltage, a change in battery pack temperature, a change in insulation resistance, etc., the control unit 31 can record the information related to the occurred event in the memory 32.

[0064] The black box battery 33 is charged by the DC-DC converter 60 in the The power supply has turned on state of the electric vehicle 1 and supplies power to the BMS 20 in the The power supply has turned off state of the electric vehicle 1, and can operate as the power supply of the battery black box 30.

[0065] The power switching unit 35 connects the black box battery 33 to one of the DC-DC converter 60 and the switching unit 80 according to the control of the control unit 31. The control unit 31 can transmit a power switching signal PSS for controlling the power switching unit 35 to the power switching unit 35.

[0066] The positive electrode BB+ of the black box battery 33 is connected to the power switching unit 35, and the negative electrode BB- of the black box battery 33 is connected to the ground. When the power switching unit 35 connects the positive electrode BB+ of the black box battery 33 and the DC-DC converter 60 under the control of the control unit 31, the black box battery 33 can be charged by the output voltage DOUT from the DC-DC converter 60. When the power switching unit 35 connects the positive electrode BB+ of the black box battery 33 and the switching unit 80 under the control of the control unit 31, the output voltage BOUT of the black box battery 33 can be transmitted to the switching unit 80.

[0067] The ECU 50 Power on and Power off information related thereto (hereinafter, Power state information ) is transmitted to the BMS 20 via the CAN bus line 90. When only the MCU 22 Power state information receives it, the MCU 22 can transmit this information to the control unit 31 by the CAN bus line 90 or another method that is not CAN communication. Not only the MCU 22 but also the control unit 31 via the communication unit 34 of the battery black box 30 Power state information can receive it. Or, only the battery black box 30 Power state information can receive it. In this way, the ECU 50 can transmit Power state information to at least one of the BMS 20 and the battery black box 30 by CAN communication.

[0068] FIG. 4 is a flowchart showing the operation of the battery system Power on or off according to an embodiment of an electric vehicle.

[0069] First, for the electric vehicle Turn on the power supply and the ECU50 Power on sense it, and corresponding to this Power state information , relay 5 generate a relay control signal RS for controlling closing, and a switching control signal PSW for connecting the auxiliary battery 70 and the BMS20. Power state information can be transmitted to at least one of the BMS20 and the battery black box 30 via the CAN bus line 90.

[0070] For the electric vehicle 1 The power supply turns on As a result, the relay 5 is closed and the DC-DC converter 60 is connected to the auxiliary battery 70 and the black box battery 33, the battery black box 30 enters a power-off state, and the BMS20 receives the supply of the power supply voltage VCC from the auxiliary battery 70 via the switching unit 80 (S1). The auxiliary battery 70 and the black box battery 33 can be charged by the output voltage DOUT supplied from the DC-DC converter 60.

[0071] FIG. 5 is a diagram schematically showing the operation of the switching unit in the The power supply is in the on state electric vehicle.

[0072] As shown in FIG. 5, the switching unit 80 connects the contact SN2 connected to the auxiliary battery 70 and the contact SN1 connected to the power supply unit 24 of the BMS20 according to the switching control signal PSW. Then, the output voltage AOUT of the auxiliary battery 70 can be supplied to the power supply voltage VCC of the BMS20.

[0073] For the electric vehicle 1 The power supply has turned on After that, the BMS20 measures a plurality of cell voltages (VC1~VCn)), measures the battery pack current and temperature, and measures the insulation resistance (S2).

[0074] For the electric vehicle 1 The power supply has turned on After that, the ECU50 continuously determines whether The power supply has turned off of the electric vehicle 1 is satisfied (S3).

[0075] The determination result of the S3 stage, The power supply is in the on state in this case, the S2 stage is performed. The determination result of the S3 stage, The power supply turns off and the ECU 50 Power off senses it and generates a corresponding Power state information relay 5 control signal RS for controlling the relay to open, and a switching control signal PSW for connecting the battery black box 30 and the BMS 20. Power state information can be transmitted to at least one of the BMS 20 and the battery black box 30 via the CAN bus line 90.

[0076] For the electric vehicle 1 The power supply turns off as a result, the relay 5 is opened, the DC-DC converter 60 is separated from the auxiliary battery 70 and the black box battery 33, the battery black box 30 is powered on, and the BMS 20 receives the supply of the power supply voltage VCC from the black box battery 33 via the switching unit 80 (S4).

[0077] FIG. 6 is a diagram schematically showing the operation of the switching unit in the electric vehicle. The power supply is in the off state

[0078] As shown in FIG. 6, the switching unit 80 connects the contact SN3 connected to the black box battery 33 and the contact SN1 connected to the power supply unit 24 of the BMS 20 according to the switching control signal PSW. Then, the output voltage BOUT of the black box battery 33 can be supplied to the power supply voltage VCC of the BMS 20.

[0079] When the battery black box 30 is powered on, the battery management information BMI generated from the BMS 20 is transmitted to the battery black box 30, and the battery black box 30 stores the received battery management information BMI (S5).

[0080] For the electric vehicle 1 The power supply has turned off after that, the ECU 50 continuously determines whether there is The power supply has turned on in the electric vehicle 1 (S6).​

[0081] S6 stage judgment result, The power supply is in the off state If so, step S5 is carried out. If step S6 is carried out, The power supply turns on Then, step S1 may be performed.

[0082] The black box battery 33 is The power supply is in the off state The black box battery 33 can be manufactured to be able to supply power to the BMS 20 for at least five days even in an EOL (End of Life) state. For reference, the EOL may be a state in which the SOH is reduced to 60%.

[0083] For example, under the conditions that the operating current of the BMS 20 is 200 mA, the power supply voltage VCC required for the operation of the BMS 20 is 12 V, the operating current of the battery black box 30 is 200 mA, and the power supply voltage VCC required for the operation of the battery black box 30 is 12 V, the black box battery 33 can be manufactured to have a capacity of 50,000 mAh (125h*200mA+125h*200mA) and an output voltage of 12 V in order for the BMS 20 and battery black box 30 to operate for approximately 5.2 days (=125 hours).

[0084] The memory 32 may be manufactured to store battery management information (CAN data) for at least one day immediately preceding the current time point. The control unit 31 writes the battery management information in the memory 32 by deleting and overwriting the oldest data among the data stored in the memory 32.

[0085] The case of the battery black box 30 can be made of a heat-resistant material such as titanium.

[0086] Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those having ordinary skill in the field to which the present invention pertains also fall within the scope of the present invention.

Claims

1. In a battery system applied to an electric vehicle, a battery pack including a plurality of battery cells; a battery management system that measures information regarding the battery pack and manages the battery pack based on the measured information; a battery black box that supplies power to the battery management system when the power source of the electric vehicle is off, acquires battery pack management information generated by the battery management system, and stores the acquired battery pack management information, wherein the battery pack management information includes information regarding at least one of a plurality of cell voltages of the plurality of battery cells, a current and temperature of the battery pack, and an insulation resistance of the battery pack; the battery black box includes a black box battery that supplies power to the battery management system when the power source of the electric vehicle is off, and the black box battery is charged when the power source of the electric vehicle is on, the battery system.

2. The battery black box includes a communication unit that receives the battery pack management information, and a control unit that receives transmission of the battery pack management information from the communication unit and stores it in a memory, the battery system according to claim 1.

3. The battery black box further includes a power switching unit that operates such that an output voltage of the black box battery is supplied to the battery management system when the power source of the electric vehicle is off, and the black box battery is charged when the power source of the electric vehicle is on, the battery system according to claim 2.

4. The communication unit receives power state information indicating off or on of the power source of the electric vehicle by CAN communication with an electronic control circuit of the electric vehicle, the control unit controls the power switching unit according to the power state information, the battery system according to claim 3.

5. The battery management system includes a first communication unit for transmitting the battery pack management information to the battery black box, the battery black box includes a second communication unit for receiving the battery pack management information, the first communication unit and the second communication unit are connected by CAN communication, the battery system according to any one of claims 1 to 4.

6. an auxiliary battery A battery system including a battery pack, a battery management system for managing the battery pack, and a battery black box that obtains battery pack management information from the battery management system when the power of the electric vehicle is off and stores the obtained battery pack management information. A switching unit that connects the auxiliary battery and the battery management system when the power of the electric vehicle is on, and connects the battery black box and the battery management system when the power of the electric vehicle is off. The battery black box Includes a black box battery for supplying power to the battery management system when the power of the electric vehicle is off. The battery pack management information includes information related to at least one of the cell voltages of a plurality of battery cells, the current and temperature of the battery pack, and the insulation resistance of the battery pack. An electric vehicle further including a DC-DC converter for charging the auxiliary battery and the black box battery when the power of the electric vehicle is on.

7. The battery black box A communication unit for receiving the battery pack management information; and The electric vehicle according to claim 6, further including a control unit that receives the transmission of the battery pack management information from the communication unit and stores it in a memory.

8. The battery black box The electric vehicle according to claim 7, further including a power switching unit that operates such that the output voltage of the black box battery is supplied to the battery management system when the power of the electric vehicle is off, and the black box battery is charged when the power of the electric vehicle is on.

9. The communication unit Receives power state information indicating the power on or off of the electric vehicle by CAN communication with the electronic control circuit of the electric vehicle. The control unit The electric vehicle according to claim 8, which controls the power switching unit according to the power state information.

10. The electric vehicle according to claim 6, further including an electronic control circuit that senses the power on or off of the electric vehicle, generates power state information, and transmits the power state information to at least one of the battery management system and the battery black box.

11. The battery management system includes a first communication unit for transmitting the battery pack management information to the battery black box. The battery black box includes a second communication unit that receives the battery pack management information, The first communication unit and the second communication unit are connected by CAN communication. The electric vehicle according to claim 10.

12. In an operation method of an electric vehicle that receives power supply from a battery system including a battery management system that manages a battery pack including a plurality of battery cells, When the power supply of the electric vehicle including the battery system is off, the battery black box supplies power to the battery management system; The battery management system acquires information regarding the battery pack and generates battery pack management information; When the power supply of the electric vehicle is off, the battery black box acquires the battery pack management information generated by the battery management system and stores the acquired battery pack management information; When the power supply of the electric vehicle is on, connecting the auxiliary battery of the electric vehicle and the battery management system, and when the power supply of the electric vehicle is off, connecting the battery black box and the battery management system; The battery pack management information includes information regarding at least one of a plurality of cell voltages of the plurality of battery cells, current and temperature of the battery pack, and insulation resistance of the battery pack; The battery black box includes a communication unit that receives the battery pack management information, a control unit that receives transmission of the battery pack management information from the communication unit and stores it in a memory, and a black box battery for supplying power to the battery management system when the power supply of the electric vehicle is off; An operation method of an electric vehicle, further including a step of charging the auxiliary battery and the black box battery when the power supply of the electric vehicle is on.

13. The operation method of the electric vehicle according to claim 12, further including a step of the auxiliary battery of the electric vehicle supplying power to the battery management system when the power supply of the electric vehicle is on.

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