Protection Method and Device for Power Battery

Abstract

The present application relates to the technical field of new energy vehicles, and particularly to a method and device for protecting a power battery. The method includes: receiving a heating request generated by a battery management system when both the current temperature and the actual state of charge of the power battery meet preset heating conditions, collecting the current state of the vehicle, determining whether the vehicle meets the preset pulse heating conditions, if so, controlling the vehicle to enter the pulse heating mode, and controlling the electric drive controller to turn on a high-frequency switch to generate a pulse current to heat the power battery. The embodiments of the present application can enable the power battery to correctly enter and exit the pulse heating function in a low-temperature environment, so that the battery can be quickly and evenly heated, while eliminating potential safety hazards caused by overvoltage and undervoltage of the battery during low-temperature pulse heating, effectively improving the service life and safety of the power battery, and ensuring the safety of the vehicle.

Description

Technical Field

[0001] The present application relates to the technical field of new energy vehicles, and in particular to a method and device for protecting a power battery. Background Art

[0002] In recent years, the application of power batteries in the automotive industry has developed rapidly, and their safety, endurance and charging issues have attracted much attention. In a low-temperature environment, high-power charging of lithium-ion power batteries may cause lithium deposition, resulting in lithium dendrites that pierce the diaphragm and cause an internal short circuit. In addition, the activity of the positive and negative electrode materials of lithium-ion batteries decreases at low temperatures, the conductivity of the electrolyte decreases, and the power usage is reduced, so the battery needs to be heated at low temperatures.

[0003] In the related technology, low-temperature pulse heating is based on the principle of heat generation inside the battery. It uses the characteristic of increased internal resistance of the battery at low temperatures, sets reasonable pulse parameters, and uses polarization differential heat under large current to quickly heat the battery. This technology can make the battery heated evenly and the heating rate is fast.

[0004] However, in the related art, the battery cell voltage is prone to exceed or fall below the protection threshold during the pulse heating process, causing safety risks to the power battery due to overvoltage or undervoltage, reducing the power battery life and safety, and increasing vehicle risk hazards. In the published patent document CN114094901A "A method for controlling the position of a motor rotor during pulse heating of a power battery", the related art performs safety protection by exiting the pulse heating function when the motor rotor position converges beyond the allowable position range during pulse heating. It cannot solve the problem of the cell voltage exceeding or falling below the protection threshold, resulting in safety hazards to the power battery, which needs to be solved urgently. Summary of the invention

[0005] The present application provides a power battery protection method and device to solve the problem in the related art that the battery cell voltage is likely to exceed or fall below the protection threshold during pulse heating, causing the power battery to pose a safety risk due to overvoltage or undervoltage, reducing the power battery life and safety, and increasing vehicle risk hazards.

[0006] The first aspect of the present application provides a method for protecting a power battery, comprising the following steps: receiving a heating request generated by a battery management system when the current temperature of the power battery and the actual battery charge state both meet preset heating conditions; collecting the current state of the vehicle, and judging whether the vehicle meets the preset pulse heating conditions based on the current state; if the vehicle meets the preset pulse heating conditions, controlling the vehicle to enter a pulse heating mode to control the electric drive controller to turn on a high-frequency switch to generate a pulse current to heat the power battery.

[0007] According to the above technical means, the embodiments of the present application can enable the power battery to correctly enter and exit the pulse heating function in a low-temperature environment, so that the battery can be quickly and evenly heated, while eliminating the potential safety hazards caused by overvoltage and undervoltage of the battery during low-temperature pulse heating, effectively improving the service life and safety of the power battery, and ensuring the safety of the vehicle.

[0008] Optionally, in an embodiment of the present application, the preset heating condition is that the current temperature is lower than or equal to the first preset temperature and the actual state of charge of the battery is greater than or equal to a preset percentage.

[0009] According to the above technical means, the embodiments of the present application can specifically define the data of the current temperature and the actual state of charge of the power battery, so as to ensure that there is an actual heating requirement for the battery currently, and avoid the risk of single-cell undervoltage of the battery during subsequent pulse heating, consolidating the safety protection foundation of the battery.

[0010] Optionally, in an embodiment of the present application, the preset pulse heating conditions include that the actual gear of the vehicle is in the parking gear, the driver's seat of the vehicle is occupied, the vehicle is in a non-drivable mode, the charging device is not connected, and the vehicle does not have a preset fault that prohibits pulse heating.

[0011] According to the above technical means, the embodiments of the present application can specifically define the current state of the vehicle, so as to ensure that the current state of the vehicle can enable the pulse heating to be safely executed, reduce the potential safety hazards during the pulse heating process, and improve the vehicle safety protection during the pulse heating process.

[0012] Optionally, in an embodiment of the present application, while heating the power battery, it further includes: obtaining the actual temperature of the power battery; when the actual temperature is greater than or equal to the second preset temperature, controlling the vehicle to exit the pulse heating mode and stop heating.

[0013] According to the above technical means, the embodiments of the present application can obtain the actual temperature of the power battery while heating the power battery, and when the actual temperature is greater than or equal to the second preset temperature, control the vehicle to exit the pulse heating mode and stop heating, so as to avoid the risk of overvoltage of the battery and ensure the safety of the battery during the pulse heating process.

[0014] Optionally, in an embodiment of the present application, after stopping heating, it further includes: generating a signal indicating that the battery pulse heating is completed; controlling at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device to give a reminder based on the signal indicating that the battery pulse heating is completed.

[0015] According to the above technical means, in the embodiment of the present application, after stopping heating, a signal indicating that the battery pulse heating is completed can be generated, and at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device can be controlled to give a reminder based on the signal indicating that the battery pulse heating is completed. By giving a multi-angle and all-round reminder to the user, the driving information of the user can be updated in a timely manner, and the driving experience of the user is improved.

[0016] An embodiment of the second aspect of the present application provides a protection device for a power battery, including: a receiving module, configured to receive a heating request generated by a battery management system when the current temperature and the actual state of charge of the power battery both meet a preset heating condition; a judging module, configured to collect the current state of the vehicle and judge whether the vehicle meets a preset pulse heating condition based on the current state; a control module, configured to control the vehicle to enter a pulse heating mode when the vehicle meets the preset pulse heating condition, so as to control an electric drive controller to turn on a high-frequency switch to generate a pulse current to heat the power battery.

[0017] Optionally, in an embodiment of the present application, the preset heating condition is that the current temperature is lower than or equal to a first preset temperature and the actual state of charge is greater than or equal to a preset percentage.

[0018] Optionally, in an embodiment of the present application, the preset pulse heating condition includes that the actual gear of the vehicle is in the parking gear, the driver's seat of the vehicle is occupied, the vehicle is in a non-drivable mode, the charging device is not connected, and the vehicle does not have a preset fault that prohibits pulse heating.

[0019] Optionally, in an embodiment of the present application, the control module includes: an obtaining unit, configured to obtain the actual temperature of the power battery while heating the power battery; a control unit, configured to control the vehicle to exit the pulse heating mode and stop heating when the actual temperature is greater than or equal to a second preset temperature.

[0020] Optionally, in an embodiment of the present application, the control module further includes: a generating unit, configured to generate a signal indicating that the battery pulse heating is completed after stopping heating; a reminding unit, configured to control at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device to give a reminder based on the signal indicating that the battery pulse heating is completed.

[0021] An embodiment of the third aspect of the present application provides a vehicle controller, including: the protection device for a power battery described above.

[0022] A fourth aspect embodiment of the present application provides a vehicle, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the protection method for the power battery as described in the above embodiments.

[0023] A fifth aspect embodiment of the present application provides a computer-readable storage medium that stores a computer program, and when the program is executed by a processor, it implements the above protection method for the power battery.

[0024] Advantages of the present application:

[0025] (1) Embodiments of the present application can enable the power battery to correctly enter and exit the pulse heating function in a low-temperature environment, thereby quickly and uniformly heating the battery, while eliminating potential safety hazards caused by overvoltage and undervoltage of the battery during low-temperature pulse heating, effectively improving the lifespan and safety of the power battery, and ensuring the safety of the vehicle.

[0026] (2) Embodiments of the present application can specifically define the data of the current temperature and actual state of charge of the power battery and the current state of the vehicle, thereby consolidating the safety protection foundation of the battery, reducing potential safety hazards during the pulse heating process, and improving the vehicle safety protection during the pulse heating process.

[0027] (3) After stopping heating, embodiments of the present application can generate a signal indicating that the battery pulse heating is completed, and control at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device to give a reminder based on the signal indicating that the battery pulse heating is completed. By giving a multi-angle and all-round reminder to the user, the driving information of the user can be updated in a timely manner, improving the driving experience of the user.

[0028] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, where:

[0030] Figure 1 is a flowchart of a protection method for a power battery according to an embodiment of the present application;

[0031] Figure 2 is a strategy for preventing overvoltage and undervoltage of single cells during low-temperature pulse heating of a lithium-ion power battery in an embodiment of the present application;

[0032] Figure 3Pulse heating start battery state of charge (SOC) and temperature overvoltage boundary curve for an embodiment of the present application;

[0033] Figure 4 Scanning electron microscope (SEM) image of the electrode sheet of the battery cell after pulse heating for an embodiment of the present application;

[0034] Figure 5 Schematic structural diagram of a protection device for a power battery according to an embodiment of the present application;

[0035] Figure 6 Schematic structural diagram of a vehicle according to an embodiment of the present application.

[0036] Among them, 10 - protection device for the power battery; 100 - receiving module, 200 - judging module, and 300 - control module; 601 - memory, 602 - processor, and 603 - communication interface. Detailed implementation manners

[0037] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as limiting the present application.

[0038] The protection method and device for a power battery according to an embodiment of the present application will be described below with reference to the accompanying drawings. In view of the problem mentioned in the above background technology that in the related art, during the pulse heating process, the voltage of the battery cell is likely to exceed or be lower than the protection threshold, causing safety risks to the power battery due to overvoltage or undervoltage, reducing the life and safety of the power battery, and increasing the risk hidden danger of the vehicle, the present application provides a protection method for a power battery. By receiving a heating request generated by the battery management system when the current temperature and the actual state of charge of the power battery both meet the preset heating conditions, collecting the current state of the vehicle, judging whether the vehicle meets the preset pulse heating conditions, if so, controlling the vehicle to enter the pulse heating mode, and controlling the electric drive controller to turn on the high-frequency switch to generate a pulse current to heat the power battery, so as to quickly and uniformly heat the battery, and at the same time eliminate the safety hidden danger caused by overvoltage and undervoltage of the battery during the low-temperature pulse heating process, effectively improving the life and safety of the power battery and ensuring the safety of the vehicle. Thus, the problems in the related art that during the pulse heating process, the voltage of the battery cell is likely to exceed or be lower than the protection threshold, causing safety risks to the power battery due to overvoltage or undervoltage, reducing the life and safety of the power battery, and increasing the risk hidden danger of the vehicle are solved.

[0039] Specifically,Figure 1 Schematic flowchart of a protection method for a power battery provided by an embodiment of the present application.

[0040] As Figure 1 shown, the protection method for the power battery includes the following steps:

[0041] In step S101, a heating request generated by the battery management system when both the current temperature and the actual state of charge of the power battery meet the preset heating conditions is received.

[0042] It can be understood that in the embodiment of the present application, the battery management system BMS (Battery Management System) can intelligently manage and maintain each battery unit and monitor the battery status to prevent the battery from overcharging and over-discharging. The preset heating conditions can be the power battery status that can meet the vehicle pulse heating execution conditions.

[0043] It should be noted that the preset heating conditions are set by those skilled in the art according to the actual situation and are not specifically limited herein.

[0044] In some embodiments, the battery management system BMS can collect the voltage and temperature of individual batteries and detect the current of the battery pack, estimate the state of charge SOC value of the battery, and send the collected information to the body control unit BCU (Body Control Module). Then, the body control unit BCU judges whether to request pulse heating according to the current temperature and the state of charge of the battery. After judging that the conditions for entering pulse heating are met, the body control unit BCU sends a heating request to the vehicle control unit VCU (Vehicle Control Unit) of the embodiment of the present application.

[0045] The embodiment of the present application can receive the heating request generated by the battery management system when both the current temperature and the actual state of charge of the power battery meet the preset heating conditions, collect the data information of the battery in multiple aspects, and comprehensively detect the battery state, thereby ensuring that the battery is in a state where it can safely execute pulse heating.

[0046] Optionally, in an embodiment of the present application, the preset heating conditions are that the current temperature is lower than or equal to the first preset temperature and the actual state of charge of the battery is greater than or equal to the preset percentage.

[0047] It can be understood that in the embodiment of the present application, the first preset temperature can be the temperature of the power battery that meets the vehicle heating request execution conditions, and the preset percentage can be the percentage value of the actual state of charge of the power battery that meets the vehicle heating request execution conditions.

[0048] It should be noted that the first preset temperature and the preset percentage are set by those skilled in the art according to the actual situation, and no specific limitation is made here.

[0049] For example, the preset heating conditions that the current temperature of the power battery and the actual state of charge of the battery need to meet can be that the current temperature is lower than or equal to -12°C, and the actual state of charge of the battery is greater than or equal to 20%. When the state of charge of the battery is less than 20%, there is a risk of monomer undervoltage when pulse heating is turned on. If the current temperature of the power battery of vehicle 1 is -14°C and the actual state of charge is 32%, then the power battery of vehicle 1 meets the preset heating conditions.

[0050] The embodiments of the present application can specifically limit the data of the current temperature and the actual state of charge of the power battery, so as to ensure that there is an actual heating requirement for the battery currently, and avoid the risk of monomer undervoltage of the battery during the subsequent pulse heating process, consolidating the safety protection foundation of the battery.

[0051] In step S102, the current state of the vehicle is collected, and based on the current state, it is judged whether the vehicle meets the preset pulse heating conditions.

[0052] It can be understood that the preset pulse heating conditions in the embodiments of the present application can be a current state of the vehicle capable of performing pulse heating, and the vehicle meets the preset pulse heating conditions means that the current state of the vehicle reaches the requirement for turning on pulse heating.

[0053] It should be noted that the preset pulse heating conditions are set by those skilled in the art according to the actual situation, and no specific limitation is made here.

[0054] In some embodiments, after the driver turns on the power supply to complete high-voltage and low-voltage power-on in a cold environment, the vehicle body sends the vehicle state information collected by each sensor to the body control unit BCU, so that the body control unit BCU judges whether to request pulse heating according to the current state information of the vehicle.

[0055] The embodiments of the present application can collect the current state of the vehicle, and based on the current state, judge whether the vehicle meets the preset pulse heating conditions. By collecting the vehicle state information in multiple directions and comprehensively detecting the current state of the vehicle, it is ensured that the vehicle is in a state where pulse heating can be safely performed.

[0056] Optionally, in an embodiment of the present application, the preset pulse heating conditions include that the actual gear of the vehicle is in the parking gear, the driver's seat of the vehicle is occupied, the vehicle is in a non-drivable mode, the charging device is not connected, and the vehicle does not have a preset fault prohibiting pulse heating.

[0057] It can be understood that in the embodiments of the present application, the drivable mode may be a mode in which when the accelerator pedal is depressed, or a certain control device is activated, or the braking system is released, the drive system of the vehicle enters a mode in which the vehicle can move. For example, for a vehicle without idling, when the vehicle is powered on and in D gear or R gear, it is in the "drivable mode" state. For a vehicle with idling, and the vehicle can be driven after shifting gears. After the vehicle is powered on and before shifting gears, it is in the "drivable mode" state. When the vehicle is in a non-drivable mode, it means that the current state of the vehicle does not meet the requirements of the drivable mode.

[0058] For example, the preset pulse conditions may be that the vehicle is in the P gear parking state, the driver's seat of the vehicle is occupied by the user, the vehicle is in a non-drivable mode, the AC / DC charging gun of the vehicle for charging is not connected to the charging pile, and there is no fault in the battery system that prohibits pulse heating.

[0059] The embodiments of the present application can specifically limit the current state of the vehicle, so as to ensure that the current state of the vehicle can enable the pulse heating to be executed safely, reduce the potential safety hazards in the pulse heating process, and improve the vehicle safety protection in the pulse heating process.

[0060] In step S103, if the vehicle meets the preset pulse heating conditions, the vehicle is controlled to enter the pulse heating mode to control the electric drive controller to turn on the high-frequency switch to generate a pulse current to heat the power battery.

[0061] It can be understood that in the embodiments of the present application, the electric drive controller IPU (Intergrated Power Unit) may be a device that controls the energy transfer between the power supply and the drive motor, and may be composed of a control signal interface circuit, a drive motor control circuit, and a drive circuit. The high-frequency switch may be a switch that can meet the high-frequency charge and discharge of the current.

[0062] For example, after it is determined that the vehicle meets the preset pulse heating conditions, the vehicle control unit VCU receives the heating gear request of "first gear" or "second gear" or "third gear" sent by the BCU. After receiving the request, the vehicle control unit VCU feedbacks that the pulse heating permission flag bit is "permitted", so as to control the vehicle to enter the pulse heating mode, and generate a pulse current by controlling the electric drive controller to turn on the high-frequency switch, so as to realize the heating of the power battery.

[0063] The embodiments of the present application can control the vehicle to enter the pulse heating mode when the vehicle meets the preset pulse heating conditions, and generate a pulse current by controlling the electric drive controller to turn on the high-frequency switch, so as to achieve the purpose of heating the power battery, realize the requirement of safe and fast charging of the power battery at low temperature, and improve the comprehensiveness and intelligence of the vehicle.

[0064] Optionally, in an embodiment of the present application, while heating the power battery, it further includes: obtaining the actual temperature of the power battery; when the actual temperature is greater than or equal to the second preset temperature, controlling the vehicle to exit the pulse heating mode and stop heating.

[0065] It can be understood that the second preset temperature in the embodiment of the present application can be the power battery temperature that satisfies the vehicle pulse heating end condition, and the battery heating process ends when the actual temperature of the power battery is greater than or equal to the second preset temperature.

[0066] It should be noted that the second preset temperature is set by those skilled in the art according to the actual situation, and no specific limitation is made here.

[0067] For example, detect the actual charge value SOC of the vehicle. If SOC ≤ 88%, directly start pulse heating and heat to the current minimum temperature T min ≥ -10°C or the current maximum temperature T max ≥ 0°C or the actual charge value SOC ≤ 15% or the minimum battery voltage V min ≤ undervoltage fault threshold + 500 mV, stop pulse heating. If SOC > 88%, judge whether the temperature satisfies T min ≤ -17°C. If not satisfied, do not start pulse heating. If satisfied with T min ≤ -17°C, then start pulse heating. During the heating process, continuously judge T min ≥ -15°C or the maximum battery voltage V max ≥ single - cell overvoltage fault threshold - 100 mV until the exit condition is met, and finally end the pulse heating process.

[0068] The embodiment of the present application can obtain the actual temperature of the power battery while heating the power battery, and when the actual temperature is greater than or equal to the second preset temperature, control the vehicle to exit the pulse heating mode and stop heating, thereby avoiding the overvoltage risk of the battery and ensuring the safety of the battery during pulse heating.

[0069] Optionally, in an embodiment of the present application, after stopping heating, it further includes: generating a battery pulse heating completion signal; controlling at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device to give a reminder based on the battery pulse heating completion signal.

[0070] In some embodiments, the acoustic reminder device may be an in-vehicle intelligent voice broadcast device. For example, the in-vehicle voice function sends a reminder to the user that the battery pulse heating is completed. The tactile reminder device may be an in-vehicle vibration device. For example, the in-vehicle intelligent system sends a seat vibration to remind the user that the battery pulse heating is completed. The optical reminder device may be an in-vehicle central control screen device. For example, after the heating is completed, the central control screen feeds back the information that "the intelligent battery pulse heating has been completed, please enjoy the comfortable driving in low temperature" to remind the user.

[0071] In the embodiments of the present application, after the heating is stopped, a signal indicating that the battery pulse heating is completed may be generated, and at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device may be controlled to give a reminder based on the signal indicating that the battery pulse heating is completed. By giving a multi-angle and all-round reminder to the user, the driving information of the user is updated in a timely manner, and the driving experience of the user is improved.

[0072] As Figure 2 shown, the working content of the embodiments of the present application will be elaborated in detail below with a specific embodiment of a strategy for preventing overvoltage and undervoltage of monomers during low-temperature pulse heating of a lithium-ion power battery.

[0073] In step S201, power-on is completed.

[0074] That is to say, after the driver gets in the car and turns on the power to complete the high-voltage and low-voltage power-on, each sensor transmits the collected information to the body controller.

[0075] In step S202, it is judged whether the current information meets the condition requirements.

[0076] That is to say, it is judged whether the current conditions are simultaneously met: the vehicle is in P gear for parking; the driver's seat is occupied; the vehicle is not in a drivable state; the AC / DC charging gun is not connected; there is no fault in the battery system that prohibits timely heating; T min ≤ -12°C; SOC ≥ 20%. If so, step S203 is executed; otherwise, the end step is executed.

[0077] In step S203, a heating gear request is sent.

[0078] That is to say, the body controller requests to send the heating gear "first gear" or "second gear" or "third gear" to the vehicle control unit VCU.

[0079] In step S204, the VCU feedbacks pulse heating.

[0080] That is to say, after receiving the request, the VCU feedbacks that the pulse heating permission flag bit is "allowed".

[0081] In step S205, it is judged whether the current SOC value meets the condition.

[0082] That is to say, it is determined whether the current SOC value satisfies the condition SOC ≤ 88%. If so, step S206 is executed; otherwise, step S208 is executed.

[0083] Step S206: Turn on pulse heating.

[0084] That is to say, turn on pulse heating.

[0085] In step S207, it is determined whether the pulse heating stop condition is satisfied.

[0086] That is to say, it is determined whether T min ≥ -10°C or T max ≥ 0°C or SOC ≤ 15% or V min ≤ the under-voltage fault threshold + 500 mV of the pulse heating stop condition. If so, the end step is executed; otherwise, step S206 is repeated.

[0087] In step S208, it is determined whether the current temperature value satisfies the condition.

[0088] That is to say, it is determined whether the current temperature value satisfies the condition T min ≤ -17°C. If so, step S209 is executed; otherwise, the end step is executed.

[0089] In step S209, turn on pulse heating.

[0090] That is to say, turn on pulse heating.

[0091] In step S210, it is determined whether the pulse heating exit condition is satisfied.

[0092] That is to say, it is determined whether T min ≥ -15°C or V max ≥ the single-cell over-voltage fault threshold - 100 mV of the pulse heating exit condition. If so, the end step is executed; otherwise, step S209 is repeated.

[0093] As Figure 3 shown, it is the pulse heating turn-on battery charge state SOC and temperature over-voltage boundary curve of a specific embodiment of the present application. It can be seen from the figure that when the pulse heating turn-on strategy is improper, there will be an over-voltage risk during the heating process.

[0094] As Figure 4As shown, it is a scanning electron microscope (SEM) image of the electrode sheet of the battery cell after pulse heating in a specific embodiment of the present application. As can be seen from the figure, after the pulse heating is carried out according to the correct strategy, slight lithium plating will occur on the negative electrode of the battery cell. By comparing and analyzing the SEM images of the lithium plating position and the normal position through scanning electron microscopy, it can be known that there is no obvious difference between the SEM images of the lithium plating position and the normal position, which indicates that the pulse heating does not damage the microstructure. The lithium iron phosphate battery is a battery that uses lithium iron phosphate (LiFePO4) as the positive electrode material.

[0095] During the pulse heating process, it is found that the ternary lithium battery is more prone to overvoltage risk than the lithium iron phosphate battery. The reason is that under the same internal resistance, the total voltage of the lithium iron phosphate assembly is only 85% of that of the ternary lithium battery, and the recharge current generated by the ternary lithium battery is greater than that generated by the lithium iron phosphate battery. Therefore, during the pulse heating process, the ternary lithium battery is more likely to generate overvoltage risk. There is the following formula.

[0096]

[0097] Where, I max is the maximum value of the recharge current generated by the ternary lithium battery, R is the internal resistance of the battery, U is the total voltage of the battery pack, C is an integral constant, and C > 0.

[0098] According to the protection method of the power battery proposed in the embodiment of the present application, it is possible to receive a heating request generated by the battery management system when the current temperature and the actual state of charge of the power battery both meet the preset heating conditions, collect the current state of the vehicle, determine whether the vehicle meets the preset pulse heating conditions, and if so, control the vehicle to enter the pulse heating mode, and control the electric drive controller to turn on the high-frequency switch to generate a pulse current to heat the power battery, so that the battery can be quickly and evenly heated, and at the same time eliminate the safety hazards caused by overvoltage and undervoltage of the battery during low-temperature pulse heating, effectively improving the life and safety of the power battery and ensuring the safety of the vehicle. Thus, it solves the problems in the related art that during the pulse heating process, it is easy for the voltage of the battery cell to exceed or be lower than the protection threshold, resulting in safety risks for the power battery due to overvoltage or undervoltage, reducing the life and safety of the power battery, and increasing the risk hazards of the vehicle.

[0099] Secondly, the protection device of the power battery proposed in the embodiment of the present application will be described with reference to the accompanying drawings.

[0100] Figure 5 It is a block diagram of the protection device of the power battery in the embodiment of the present application.

[0101] As Figure 5 shown, the protection device 10 of the power battery includes: a receiving module 100, a judging module 200, and a control module 300.

[0102] Among them, the receiving module 100 is used to receive a heating request generated by the battery management system when both the current temperature of the power battery and the actual state of charge of the battery meet the preset heating conditions.

[0103] The judgment module 200 is used to collect the current state of the vehicle and judge whether the vehicle meets the preset pulse heating conditions based on the current state.

[0104] The control module 300 is used to control the vehicle to enter the pulse heating mode when the vehicle meets the preset pulse heating conditions, so as to control the electric drive controller to turn on the high-frequency switch to generate a pulse current to heat the power battery.

[0105] Optionally, in an embodiment of the present application, the preset heating conditions are that the current temperature is lower than or equal to the first preset temperature and the actual state of charge of the battery is greater than or equal to the preset percentage.

[0106] Optionally, in an embodiment of the present application, the preset pulse heating conditions include that the actual gear of the vehicle is in the parking gear, the driver's seat of the vehicle is occupied, the vehicle is in a non-drivable mode, the charging device is not connected, and the vehicle does not have a preset fault that prohibits pulse heating.

[0107] Optionally, in an embodiment of the present application, the control module 300 includes: an acquisition unit and a control unit.

[0108] Among them, the acquisition unit is used to acquire the actual temperature of the power battery while heating the power battery.

[0109] The control unit is used to control the vehicle to exit the pulse heating mode and stop heating when the actual temperature is greater than or equal to the second preset temperature.

[0110] Optionally, in an embodiment of the present application, the control module 300 further includes: a generation unit and a reminder unit.

[0111] Among them, the generation unit is used to generate a signal indicating that the battery pulse heating is completed after stopping heating.

[0112] The reminder unit is used to control at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device to give a reminder based on the signal indicating that the battery pulse heating is completed.

[0113] It should be noted that the foregoing explanation of the embodiments of the protection method for the power battery also applies to the protection device for the power battery in this embodiment, and will not be repeated here.

[0114] The protection device for a power battery according to an embodiment of the present application can receive a heating request generated by a battery management system when both the current temperature and the actual state of charge of the power battery meet a preset heating condition, collect the current state of the vehicle, determine whether the vehicle meets the preset pulse heating condition, and if so, control the vehicle to enter the pulse heating mode and control the electric drive controller to turn on a high-frequency switch to generate a pulse current to heat the power battery, so as to quickly and evenly raise the temperature of the battery, and at the same time eliminate the safety hazards caused by overvoltage and undervoltage of the battery during low-temperature pulse heating, effectively improving the service life and safety of the power battery and ensuring the safety of the vehicle. Thus, the problems in the related art are solved, such as in the pulse heating process, it is easy for the voltage of a single battery cell to exceed or be lower than the protection threshold, causing safety risks to the power battery due to overvoltage or undervoltage, reducing the service life and safety of the power battery, and increasing the risk hazards of the vehicle.

[0115] This embodiment also provides a vehicle controller that can implement the above-mentioned protection device for a power battery.

[0116] A vehicle controller according to an embodiment of the present application receives a heating request generated by a battery management system when both the current temperature and the actual state of charge of the power battery meet a preset heating condition, collects the current state of the vehicle, determines whether the vehicle meets the preset pulse heating condition, and if so, controls the vehicle to enter the pulse heating mode and controls the electric drive controller to turn on a high-frequency switch to generate a pulse current to heat the power battery, so as to quickly and evenly raise the temperature of the battery, and at the same time eliminate the safety hazards caused by overvoltage and undervoltage of the battery during low-temperature pulse heating, effectively improving the service life and safety of the power battery and ensuring the safety of the vehicle. Thus, the problems in the related art are solved, such as in the pulse heating process, it is easy for the voltage of a single battery cell to exceed or be lower than the protection threshold, causing safety risks to the power battery due to overvoltage or undervoltage, reducing the service life and safety of the power battery, and increasing the risk hazards of the vehicle.

[0117] Figure 6 It is a schematic structural diagram of a vehicle provided by an embodiment of the present application. The vehicle may include:

[0118] A memory 601, a processor 602, and a computer program stored on the memory 601 and executable on the processor 602.

[0119] When the processor 602 executes the program, it implements the protection method for the power battery provided in the above embodiment.

[0120] Further, the vehicle further includes:

[0121] A communication interface 603 for communication between the memory 601 and the processor 602.

[0122] A memory 601 for storing a computer program that can run on a processor 602.

[0123] The memory 601 may include a high-speed RAM memory and may also include non-volatile memory, such as at least one disk memory.

[0124] If the memory 601, the processor 602, and the communication interface 603 are implemented independently, the communication interface 603, the memory 601, and the processor 602 can be interconnected through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 6 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0125] Optionally, in a specific implementation, if the memory 601, the processor 602, and the communication interface 603 are integrated on a single chip, the memory 601, the processor 602, and the communication interface 603 can communicate with each other through an internal interface.

[0126] The processor 602 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0127] This embodiment also provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the protection method of the power battery as described above is implemented.

[0128] In the description of this specification, the descriptions with reference to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0129] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0130] Any process or method description shown in the flowchart or described in other ways herein can be understood as representing a module, segment, or part of code including one or N executable instructions for implementing a customized logic function or process, and the scope of the preferred embodiments of this application includes additional implementations, where the functions can be executed in a substantially simultaneous manner or in the reverse order according to the functions involved, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of this application belong.

[0131] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in combination with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in combination with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection part (electronic device) having one or N wirings, a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0132] It should be understood that various parts of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0133] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the method of implementing the above embodiments can be completed by a program instructing relevant hardware, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0134] In addition, each functional unit in various embodiments of the present application may be integrated into a processing module, may exist separately physically for each unit, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0135] The above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disc, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A protection method for a power battery, characterized in that It includes the following steps: Receiving a heating request generated by a battery management system when both the current temperature and the actual state of charge of a power battery meet a preset heating condition; The preset heating condition is that the current temperature is lower than or equal to a first preset temperature and the actual state of charge is greater than or equal to a first preset percentage; Collecting the current state of the vehicle and determining whether the vehicle meets a preset pulse heating condition based on the current state; The preset pulse heating condition includes that the actual state of charge of the power battery is less than or equal to 88%, or the actual state of charge of the power battery is greater than 88% and the current temperature of the power battery is less than or equal to -17°C; And If the vehicle meets the preset pulse heating condition, controlling the vehicle to enter a pulse heating mode to control an electric drive controller to turn on a high-frequency switch to generate a pulse current to heat the power battery.

2. The method according to claim 1, characterized in that, The preset pulse heating condition includes that the actual gear of the vehicle is in the park gear, the driver's seat of the vehicle is occupied, the vehicle is in a non-drivable mode, the charging device is not connected, and the vehicle does not have a preset fault prohibiting pulse heating.

3. The method according to claim 1, wherein While heating the power battery, it further includes: Obtaining the actual temperature of the power battery; When the actual temperature is greater than or equal to a second preset temperature, controlling the vehicle to exit the pulse heating mode and stop heating.

4. The method according to claim 3, wherein After stopping heating, it further includes: Generating a battery pulse heating completion signal; Controlling at least one acoustic reminder device, at least one tactile reminder device, and / or at least one optical reminder device to give a reminder based on the battery pulse heating completion signal.

5. A protection device for a power battery, characterized in that, It includes: A receiving module, configured to receive a heating request generated by a battery management system when both the current temperature and the actual state of charge of a power battery meet a preset heating condition; the preset heating condition is that the current temperature is lower than or equal to a first preset temperature and the actual state of charge is greater than or equal to a first preset percentage; A judging module, configured to collect the current state of the vehicle and determine whether the vehicle meets a preset pulse heating condition based on the current state; the preset pulse heating condition includes that the actual state of charge of the power battery is less than or equal to 88%, or the actual state of charge of the power battery is greater than 88% and the current temperature of the power battery is less than or equal to -17°C; And A control module, configured to control the vehicle to enter a pulse heating mode when the vehicle meets the preset pulse heating condition, so as to control an electric drive controller to turn on a high-frequency switch to generate a pulse current to heat the power battery.

6. The device according to claim 5, characterized in that The preset pulse heating condition includes that the actual gear of the vehicle is in the park gear, the driver's seat of the vehicle is occupied, the vehicle is in a non-drivable mode, the charging device is not connected, and the vehicle does not have a preset fault prohibiting pulse heating.

7. A vehicle controller, comprising: The protection device for a power battery according to any one of claims 5-6.

8. A vehicle, characterized in that, It includes: A memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to implement the protection method for a power battery as described in any one of claims 1-4.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the protection method for a power battery as described in any one of claims 1-4.

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