Thermal management method of power battery and battery management system

Abstract

The invention relates to the technical field of battery management, in particular to a thermal management method of a power battery and a battery management system.The method comprises the steps that when a vehicle is in a thermal management working condition, the whole vehicle wheel end power of the vehicle is predicted; according to the whole vehicle wheel end power and the power transmission efficiency of the power battery, the whole vehicle required power of the power battery is predicted; and according to the current power battery state and the current cooling state of the power battery and the power battery power required by the whole vehicle, a heat management control action of the power battery meeting the preset energy-saving condition is generated, and the vehicle is controlled to execute the heat management control action. Therefore, the problems that power management of the power battery in the related technology has certain hysteresis and redundancy, when the vehicle enters cooling later or the power of the power battery is large / small subsequently, the power of the power battery is possibly reduced, so that the running of the whole vehicle is influenced, or the cooling amount is wasted, and the control of the power battery thermal management cannot be timely and accurately realized are solved; and the endurance mileage of a power battery of the vehicle is influenced.

Description

Technical Field

[0001] The present application relates to the field of battery management technology, and in particular to a thermal management method and a battery management system for a power battery. Background Art

[0002] In the related technologies, the power battery thermal management system mostly inputs and outputs power according to the needs of the vehicle and its own power capacity. The power battery generates heat according to its own characteristics, causing its own temperature to rise. After reaching a certain temperature and satisfying the power battery thermal management cooling conditions, cooling is triggered and a certain amount of cooling is requested. Under this method, if the cooling is entered late or the subsequent power battery power is large, causing the subsequent power battery to heat up too quickly, the power battery power may drop, thereby affecting the driving of the vehicle. If the subsequent power battery power is small, causing the subsequent power battery to heat up slowly, requesting a large amount of cooling will result in a waste of cooling.

[0003] However, the power battery thermal management in the related technology has certain lags and redundancies. When the cooling starts late or the subsequent power battery power is larger / smaller, the power battery power may drop and affect the driving of the whole vehicle, or cause a waste of cooling. It is impossible to timely and accurately control the power battery thermal management, affecting the vehicle's power battery range, which needs to be solved urgently. Summary of the invention

[0004] The present application provides a thermal management method and a battery management system for a power battery to solve the problem that the thermal management of the power battery in the related art has certain lag and redundancy. When the cooling is entered late or the subsequent power battery power is large / small, the power battery power may decrease and affect the driving of the whole vehicle, or cause a waste of cooling amount, and the thermal management of the power battery cannot be controlled in a timely and accurate manner, affecting the vehicle's power battery range.

[0005] The first aspect of the present application provides a thermal management method for a power battery, comprising the following steps: predicting the entire wheel-end power of the vehicle when the vehicle is in a thermal management condition; predicting the vehicle's entire required power battery power based on the entire wheel-end power and the power transmission efficiency of the power battery; generating a thermal management control action for the power battery that meets preset energy-saving conditions based on the current power battery state and the current cooling state of the power battery and the vehicle's entire required power battery power, and controlling the vehicle to perform the thermal management control action.

[0006] Through the above technical means, the embodiment of the present application can predict the vehicle's wheel-end power and the vehicle's required power battery power, and generate a thermal management control action that meets the preset energy-saving conditions in combination with the current power battery state and the current cooling state of the power battery for execution. The prediction method avoids the lag between thermal management and actual execution. Different power battery thermal management control strategies maintain the power battery within a reasonable range without affecting the driving of the vehicle, and can effectively reduce the cooling energy consumption required for power battery thermal management, which is simple and effective to meet the vehicle's thermal management needs.

[0007] Optionally, in one embodiment of the present application, the predicting of the whole wheel-end power of the vehicle includes: obtaining road information for traveling to the target location and obtaining whole vehicle information of the vehicle; and predicting the whole wheel-end power of the vehicle based on the road information and the whole vehicle information.

[0008] Through the above technical means, the embodiments of the present application can combine the road information and vehicle information of the vehicle to predict the vehicle's entire wheel-end power, effectively improving the accuracy of the vehicle's entire wheel-end power, and thereby improving the accuracy of thermal management of the power battery.

[0009] Optionally, in one embodiment of the present application, the obtaining of road information for traveling to the target location includes: obtaining at least one of the distance between the starting point and the target location, the slope, the traffic light information, and the traffic information as the road information.

[0010] Through the above technical means, the embodiment of the present application can obtain the distance, slope, traffic light information and traffic information of the vehicle to the target location as road information, so as to predict the whole wheel end power based on the road information, and provide certain information support for predicting the whole wheel end power.

[0011] Optionally, in one embodiment of the present application, obtaining the whole vehicle information of the vehicle includes: obtaining the vehicle drag coefficient and mass of the vehicle, and identifying the user's driving habits; generating the whole vehicle information according to the vehicle drag coefficient, the mass and the driving habits.

[0012] Through the above technical means, the embodiments of the present application can incorporate the vehicle's vehicle drag coefficient, mass, and user driving habits as whole vehicle information into the consideration factors for the whole wheel-end power prediction, effectively improving the accuracy of the prediction.

[0013] Optionally, in one embodiment of the present application, before predicting the whole wheel end power of the vehicle, it also includes: detecting whether a preset management condition is met at the current moment; and starting to predict the whole wheel end power when the preset management condition is met.

[0014] Through the above technical means, the embodiment of the present application can first detect whether the vehicle meets certain management conditions before predicting the power of the entire wheel end. If there is no need to perform thermal management on the vehicle's power battery, the power of the entire wheel end will not be predicted, which reduces the computing cost of the vehicle while effectively improving the intelligence level of the present application.

[0015] Optionally, in one embodiment of the present application, the thermal management control action of the power battery that meets preset energy-saving conditions is generated according to the current power battery state and the current cooling state of the power battery and the power battery power required by the whole vehicle, including: inputting the current power battery state, the current cooling state, and the power battery power required by the whole vehicle into a pre-built power battery thermal management control model to obtain a power battery target value, coolant flow rate, and coolant temperature that meet the preset energy-saving conditions; and generating the thermal management control action based on the power battery target value, the coolant flow rate, and the coolant temperature.

[0016] Through the above technical means, the embodiment of the present application can obtain the response surface of the power battery for different power battery thresholds entering cooling, coolant flow rates and coolant temperatures under the predicted required power battery power according to the power battery thermal management control model, and finally obtain the matching combination of the power battery threshold, coolant flow rate and coolant temperature with the minimum required cooling amount, thereby achieving the power battery within a reasonable range while avoiding affecting the driving of the entire vehicle, and reducing the cooling energy consumption required for the thermal management of the power battery.

[0017] The second aspect of the present application provides a battery management system, including: a first prediction module, used to predict the whole wheel-end power of the vehicle when the vehicle is in a thermal management condition; a second prediction module, used to predict the whole vehicle required power battery power of the vehicle based on the whole wheel-end power and the power transmission efficiency of the power battery; a management module, used to generate a thermal management control action of the power battery that meets preset energy-saving conditions based on the current power battery state and the current cooling state of the power battery and the whole vehicle required power battery power, and control the vehicle to perform the thermal management control action.

[0018] Through the above technical means, the embodiment of the present application can predict the vehicle's wheel-end power and the vehicle's required power battery power, and generate a thermal management control action that meets the preset energy-saving conditions in combination with the current power battery state and the current cooling state of the power battery for execution. The prediction method avoids the lag between thermal management and actual execution. Different power battery thermal management control strategies maintain the power battery within a reasonable range without affecting the driving of the vehicle, and can effectively reduce the cooling energy consumption required for power battery thermal management, which is simple and effective to meet the vehicle's thermal management needs.

[0019] Optionally, in one embodiment of the present application, the first prediction module includes: an acquisition unit, used to obtain road information for traveling to the target location and obtain vehicle information of the vehicle; a first prediction unit, used to predict the entire wheel-end power of the vehicle based on the road information and the entire vehicle information.

[0020] Through the above technical means, the embodiments of the present application can combine the road information and vehicle information of the vehicle to predict the vehicle's entire wheel-end power, effectively improving the accuracy of the vehicle's entire wheel-end power, and thereby improving the accuracy of thermal management of the power battery.

[0021] Optionally, in one embodiment of the present application, the acquisition unit includes: a first acquisition subunit, used to acquire at least one of the distance, slope, traffic light information, and traffic information between the starting point and the target location as the road information.

[0022] Through the above technical means, the embodiment of the present application can obtain the distance, slope, traffic light information and traffic information of the vehicle to the target location as road information, so as to predict the whole wheel end power based on the road information, and provide certain information support for predicting the whole wheel end power.

[0023] Optionally, in one embodiment of the present application, the acquisition unit includes: a second acquisition sub-unit, used to acquire the vehicle drag coefficient and mass of the vehicle and identify the user's driving habits; a generation sub-unit, used to generate the whole vehicle information based on the vehicle drag coefficient, the mass and the driving habits.

[0024] Through the above technical means, the embodiments of the present application can incorporate the vehicle's vehicle drag coefficient, mass, and user driving habits as whole vehicle information into the consideration factors for the whole wheel-end power prediction, effectively improving the accuracy of the prediction.

[0025] Optionally, in one embodiment of the present application, it also includes: a detection module, used to detect whether the preset management conditions are met at the current moment before predicting the whole wheel end power of the vehicle; a third prediction module, used to start predicting the whole wheel end power when the preset management conditions are met.

[0026] Through the above technical means, the embodiment of the present application can first detect whether the vehicle meets certain management conditions before predicting the power of the entire wheel end. If there is no need to perform thermal management on the vehicle's power battery, the power of the entire wheel end will not be predicted, which reduces the computing cost of the vehicle while effectively improving the intelligence level of the present application.

[0027] Optionally, in one embodiment of the present application, the management module includes: an input unit, used to input the current power battery state, the current cooling state, and the required power battery power of the whole vehicle into a pre-built power battery thermal management control model to obtain the power battery target value, coolant flow rate and coolant temperature that meet the preset energy-saving conditions; a generation unit, used to generate the thermal management control action based on the power battery target value, the coolant flow rate and the coolant temperature.

[0028] Through the above technical means, the embodiment of the present application can obtain the response surface of the power battery for different power battery thresholds entering cooling, coolant flow rates and coolant temperatures under the predicted required power battery power according to the power battery thermal management control model, and finally obtain the matching combination of the power battery threshold, coolant flow rate and coolant temperature with the minimum required cooling amount, thereby achieving the power battery within a reasonable range while avoiding affecting the driving of the entire vehicle, and reducing the cooling energy consumption required for the thermal management of the power battery.

[0029] A third aspect of the present application provides a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the thermal management method for a power battery as described in the above embodiment.

[0030] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned thermal management method for a power battery.

[0031] A fifth aspect of the present application provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned thermal management method for a power battery.

[0032] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0034] Figure 1 A flowchart of a thermal management method for a power battery provided according to an embodiment of the present application;

[0035] Figure 2 This is a flow chart of a thermal management method for a power battery according to an embodiment of the present application;

[0036] Figure 3A schematic diagram of the structure of a battery management system provided according to an embodiment of the present application;

[0037] Figure 4 It is a schematic diagram of the structure of a vehicle provided according to an embodiment of the present application.

[0038] Reference numerals:

[0039] 10-battery management system: 100-first prediction module, 200-second prediction module and 300-management module; 401-memory, 402-processor and 403-communication interface. DETAILED DESCRIPTION

[0040] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0041] The following describes the thermal management method and battery management system of the power battery of the embodiment of the present application with reference to the accompanying drawings. In view of the fact that the thermal management of the power battery in the related art mentioned in the above background technology has certain hysteresis and redundancy, when facing the late cooling or the subsequent power battery power is large / small, it may cause the power of the power battery to drop and affect the driving of the whole vehicle, or cause the waste of cooling, and fail to timely and accurately realize the control of the thermal management of the power battery, affecting the vehicle's power battery range. The present application provides a thermal management method for a power battery, in which the vehicle's wheel-end power and the vehicle's required power battery power can be predicted, and the thermal management control action that meets the preset energy-saving conditions is generated and executed in combination with the current power battery state and the current cooling state of the power battery. As a result, the vehicle's driving power demand and the vehicle's required power battery power are predicted based on the vehicle's driving road information, vehicle information, driving habits, power transmission efficiency, etc., avoiding the lag between the generation and actual execution of thermal management strategies. Through the power battery thermal management control model, the power battery SOC, temperature and other related power battery information are quickly predicted and calculated, and different power battery thermal management control strategies are generated to ensure that the power battery is within a reasonable range without affecting the driving of the entire vehicle. The cooling energy consumption required for power battery thermal management can be effectively reduced, and the vehicle's thermal management needs can be met simply and effectively. As a result, the problem of certain lag and redundancy in power battery thermal management in related technologies is solved. When cooling is entered late or the subsequent power battery power is large / small, the power battery power may drop and affect the driving of the entire vehicle, or cause a waste of cooling, and the power battery thermal management control cannot be realized in a timely and accurate manner, affecting the vehicle's power battery range.

[0042] Specifically, Figure 1 A flow chart of a thermal management method for a power battery provided in an embodiment of the present application.

[0043] like Figure 1 As shown, the thermal management method of the power battery includes the following steps:

[0044] In step S101, when the vehicle is in a thermal management condition, the entire wheel-end power of the vehicle is predicted.

[0045] In some embodiments, the vehicle will release a certain amount of heat during driving, which will cause the temperature of the vehicle components to rise. The power battery of the electric vehicle is a major temperature-raising component. At this time, it is necessary to use coolant or other heat dissipation functions to complete the transmission and circulation of heat to maintain the temperature stability of the power battery, that is, to perform thermal management on the vehicle's power battery. It can be understood that the vehicle is in a thermal management state at this time.

[0046] Wheel-end power, also commonly referred to as wheel power, refers to the power generated when the vehicle tire contacts the ground. It is the power source for the vehicle to travel. Wheel-end power has an important impact on the performance and efficiency of the vehicle. Its size is not only related to the output power of the engine, but also affected by many factors such as the efficiency of the transmission system, the grip of the tire, and the external environmental conditions.

[0047] When the vehicle is in a thermal management condition, as the demand for the vehicle increases, the demand for the thermal management system of the entire wheel-end power will gradually increase. Based on this, the embodiment of the present application can predict the entire wheel-end power of the vehicle, for example, once every one minute.

[0048] The embodiments of the present application can predict the entire wheel-end power of the vehicle when the vehicle is in a thermal management condition, thereby ensuring that the normal demand of the power battery can be maintained, which helps to achieve more accurate thermal management of the vehicle.

[0049] Optionally, in one embodiment of the present application, before predicting the whole wheel end power of the vehicle, it also includes: detecting whether the preset management conditions are met at the current moment; and starting to predict the whole wheel end power when the preset management conditions are met.

[0050] It is understood that the preset management conditions here can be understood as a series of rules, standards or conditions that need to be met before thermal management of the vehicle, such as abnormal engine temperature of the vehicle. The preset management conditions can be set or adjusted by professionals in this field according to the actual situation or actual needs of the vehicle, which is only an example and not a specific limitation.

[0051] In the actual implementation process, the temperature of some components may become abnormal during the driving of the vehicle. Correspondingly, the temperature of each component of the vehicle may also remain stable during the driving process, and thermal management is not required at this time. Therefore, before predicting the vehicle's entire wheel-end power, the embodiment of the present application also needs to detect whether the vehicle meets certain management conditions at this time, for example, whether the temperature of the power battery is abnormal. Only when the vehicle meets certain management conditions, that is, the temperature of the power battery is abnormal and thermal management is required, such as cooling by coolant, etc., can the entire wheel-end power be predicted.

[0052] The embodiment of the present application can first detect whether the vehicle meets certain management conditions before predicting the power of the entire wheel end. The limitation of the management conditions can effectively avoid wasting cooling resources and unnecessary cooling energy consumption when there is no need to perform thermal management on the vehicle's power battery.

[0053] Optionally, in one embodiment of the present application, predicting the entire wheel-end power of a vehicle includes: obtaining road information for traveling to a target location and obtaining entire vehicle information of the vehicle; and predicting the entire wheel-end power of the vehicle based on the road information and the entire vehicle information.

[0054] It is understandable that the target location here can be understood as the end point of the vehicle's current driving route. For example, the vehicle travels from location A to location B, and at this time, location B can be understood as the target location in the embodiment of the present application.

[0055] In other embodiments, considering that the road condition information of the vehicle's driving route will affect the overall power demand and heat of the vehicle, for example, a flat road section will have a lower power demand than a steep road section. Therefore, the embodiment of the present application can obtain the road information of the vehicle traveling to the target location, such as the total distance of the vehicle's current driving route, the slope of the driving road, etc., so as to better manage the thermal performance of the vehicle.

[0056] Furthermore, various parameter information of the vehicle itself will also affect the power demand and heat of the vehicle, for example, the size, component status, mass, etc. of the vehicle will have a certain impact. Therefore, the embodiment of the present application can also obtain the vehicle information of the vehicle to predict the vehicle's wheel-end power in combination with the road information and the vehicle information.

[0057] For example, after obtaining the road information of the vehicle traveling to the target location, the predicted speed V-time curve can be generated, and the vehicle information such as vehicle drag coefficient, vehicle mass m, etc. can be obtained at the same time. At this time, the wheel-end power can be predicted based on these road information and vehicle information. The formula can be expressed as follows:

[0058] P L =[mg*sin(θ)+F0+F1*V+F2*V*V]*V

[0059] Where V represents the speed curve, m represents the vehicle mass, g represents the acceleration of gravity, θ represents the road slope, the constant term coefficient F0, the first-order term coefficient F1 and the second-order term coefficient F2 represent the vehicle resistance coefficient, P L Indicates wheel end power.

[0060] The embodiments of the present application can combine the road information and vehicle information of the vehicle to predict the vehicle's entire wheel-end power, effectively improving the accuracy of the vehicle's entire wheel-end power, thereby improving the accuracy of thermal management of the power battery.

[0061] Optionally, in one embodiment of the present application, obtaining road information for traveling to a target location includes: obtaining at least one of the distance between a starting point and the target location, a slope, traffic light information, and traffic information as road information.

[0062] Based on the relevant descriptions of other embodiments, it can be understood that the road information of the vehicle traveling to the target location is used when predicting the vehicle's entire wheel-end power. Specifically, when obtaining the road information, it includes but is not limited to at least one of the distance between the starting point and the target location, the slope, the traffic light information, and the traffic information.

[0063] It should be noted that the content and acquisition of road information can be set or adjusted by professionals in this field according to actual conditions or needs. This is only an example and is not specifically limited.

[0064] For example, the present application can obtain the road information of the vehicle user from point A to point B based on the in-vehicle map system: distance, slope, traffic lights, congestion conditions, etc.

[0065] The embodiment of the present application can obtain the distance, slope, traffic light information and traffic information from the vehicle to the target location as road information, so as to predict the whole wheel end power based on the road information, and provide certain information support for predicting the whole wheel end power.

[0066] Optionally, in one embodiment of the present application, obtaining whole vehicle information of the vehicle includes: obtaining the vehicle drag coefficient and mass of the vehicle, and identifying the user's driving habits; generating whole vehicle information based on the vehicle drag coefficient, mass and driving habits.

[0067] In other embodiments, in addition to road information, the present application can also combine the vehicle's entire vehicle information to jointly predict the vehicle's entire wheel-end power, comprehensively consider the factors affecting the entire wheel-end power, and thus effectively improve the accuracy of the entire wheel-end power prediction results.

[0068] For example, the present application can obtain the vehicle drag coefficient and mass of the vehicle. Among them, the vehicle drag coefficient can be understood as the coefficient of the resistance encountered by the vehicle in motion that is proportional to the square of its speed, and the mass can be understood as the current mass of the vehicle. For example, cars, vans and trucks and different loads will have different masses. The drag coefficient affects the driving resistance and energy consumption of the vehicle, and then affects the power demand of the power battery. The smaller the drag coefficient, the smaller the required power. The greater the mass of the vehicle, the greater the power required during acceleration and driving.

[0069] Furthermore, considering the different driving habits of users, for example, some users are used to adventurous driving, while some users may be used to steady driving, then different types of driving styles will generate different heat and increase the temperature. For example, the temperature increase caused by the tires of a vehicle in the case of sudden acceleration, sudden braking, and constant speed driving is different, and the rolling resistance, grip and other properties of the tires will also affect the driving resistance and power demand of the vehicle. For example, low rolling resistance tires can reduce rolling resistance and power consumption, and frequent sudden acceleration will increase the instantaneous power demand of the power battery.

[0070] The embodiment of the present application can incorporate the vehicle's drag coefficient, mass, and user driving habits as whole vehicle information into the consideration factors for the whole wheel-end power prediction, thereby effectively improving the accuracy of the prediction.

[0071] Step S102, predicting the vehicle's required power battery power according to the vehicle's wheel-end power and the power transmission efficiency of the power battery.

[0072] In certain embodiments, after obtaining the entire wheel-end power of the vehicle, the embodiments of the present application can predict the vehicle's entire vehicle required power battery power in combination with the power transmission efficiency of the power battery.

[0073] Among them, the power transmission efficiency of the vehicle can be understood as the efficiency of the power generated by the engine being transmitted to the wheels through the transmission system such as the gearbox, drive shaft, differential and other components. This efficiency will affect the overall power performance of the vehicle.

[0074] For example, Represents the power transmission efficiency, then the formula for predicting the vehicle's required power battery power can be expressed as follows:

[0075]

[0076] Among them, P L is the wheel end power, Indicates power transmission efficiency, P R Indicates the predicted required power battery power.

[0077] Step S103, generating a thermal management control action for the power battery that meets a preset energy-saving condition according to the current power battery state and the current cooling state of the power battery and the power battery power required by the whole vehicle, and controlling the vehicle to execute the thermal management control action.

[0078] It is understandable that the preset energy-saving condition here can be understood as a certain rule or standard that needs to be met in advance, for example, the temperature of the power battery drops to a certain temperature, and the power demand of the power battery needs to be met, etc. It can be set or adjusted by professionals in this field according to actual conditions, and is only illustrative here without specific limitation.

[0079] As a possible implementation method, when performing thermal management on the power battery, the embodiment of the present application can combine the current power battery state, the current cooling state and the obtained vehicle required power battery power to generate a thermal management control action for the power battery that meets certain energy-saving conditions.

[0080] Among them, the current power battery status includes but is not limited to status information such as the current power battery SOC, voltage, temperature and available power, and the current cooling status includes but is not limited to status information such as the current power battery cooling system's water inlet temperature, water outlet temperature and water inlet flow.

[0081] For example, the present application can input the current power battery state and current cooling state of the power battery and the power battery power required by the entire vehicle into the relevant thermal management control model, predict the power battery state change process and the most energy-saving power battery thermal management control strategy and output them. The power battery management system can output the most energy-saving power battery thermal management control strategy to the relevant control party of the vehicle for execution.

[0082] Specifically, when the current temperature of the power battery is too high and is in an uncooled state, and the predicted power battery power required for the whole vehicle cannot be met, the power battery that can be provided by the power battery pack temperature and SOC prediction can be compared with the predicted power battery power required for the whole vehicle. When the predicted power battery power required for the whole vehicle is met and the power battery temperature does not exceed the appropriate range, the power battery control strategy with the minimum required coolant heat transfer energy is selected and output to the relevant control party for execution.

[0083] The embodiment of the present application can combine the predicted power battery power required by the whole vehicle with the current power battery state and current cooling state of the power battery to generate certain thermal management control actions, thereby avoiding the lag that may be caused between the decision-making of the thermal management system and the execution of the vehicle, ensuring that the power battery is maintained within a reasonable range while greatly avoiding the waste of cooling resources.

[0084] Optionally, in one embodiment of the present application, a thermal management control action for the power battery that meets preset energy-saving conditions is generated according to the current power battery state and the current cooling state of the power battery and the power battery power required by the whole vehicle, including: inputting the current power battery state, the current cooling state, and the power battery power required by the whole vehicle into a pre-built power battery thermal management control model to obtain a power battery target value, coolant flow rate, and coolant temperature that meet the preset energy-saving conditions; and generating a thermal management control action based on the power battery target value, the coolant flow rate, and the coolant temperature.

[0085] During the actual execution process, when generating the thermal management control action of the power battery, the present application can input the current power battery state and the current cooling state of the power battery and the predicted power battery power required by the whole vehicle into a pre-built power battery thermal management control model, thereby obtaining the power battery target value, coolant flow rate and coolant temperature that meet certain energy-saving conditions, and generate a thermal management control action based on the obtained power battery target value, coolant flow rate and coolant temperature.

[0086] For example, the present application can calculate the final predicted power battery power based on the power capacity of the power battery itself and the predicted power battery power required by the whole vehicle. The formula can be expressed as follows:

[0087] P R =min(P B ,P C )

[0088] Among them, P C Indicates the power capability of the power battery itself, P R Represents the predicted power battery power, P B Indicates the predicted required battery power of the vehicle.

[0089] Next, the embodiment of the present application may, but is not limited to, use a second-order RC model equivalent cell circuit model to predict the power battery state.

[0090] Single cell voltage U L The formula can be expressed as:

[0091] U L (t+Δt)=U OCV -ir1(t+Δt)*R1-ir2(t+Δt)*R2-i(t+Δt)*R0

[0092]

[0093] ir1(0)=i(0)

[0094] ir2(0)=i(0)

[0095] Among them, U OCV is the open circuit voltage, R0 is the ohmic internal resistance, R1 is the electrochemical polarization internal resistance, C1 is the electrochemical polarization capacitor, R2 is the concentration polarization internal resistance, C2 is the concentration polarization capacitor, ir1 is the electrochemical polarization current, ir2 is the concentration polarization current, i is the cell current, U L is the single cell voltage, t is the current time, Δt is the time interval, ir1(0) is the initial electrochemical polarization current, ir2(0) is the initial concentration polarization current, and i(0) is the initial cell current.

[0096] Power battery pack voltage U T The formula can be expressed as:

[0097] U T =n s *U L

[0098] Among them, n s It is the number of strings in a pack of power batteries.

[0099] Power battery pack current I T The formula can be expressed as:

[0100] I T =P R / U L

[0101] The SOC formula of the whole power battery pack can be expressed as:

[0102]

[0103] Among them, C nom It is the capacity of power battery cell.

[0104] The heat formula of a single cell can be expressed as:

[0105]

[0106] Among them, n P Indicates the number of power batteries connected in parallel.

[0107] Coolant heat transfer power P liq The formula can be expressed as:

[0108]

[0109] Among them, C liq is the specific heat capacity of the coolant, T Cell is the cell temperature, T liq is the coolant temperature, is the coolant mass flow rate, h liq is the thermal conductivity of the coolant, Aliq It is the contact area between coolant and power battery.

[0110] The cell temperature formula can be expressed as:

[0111]

[0112] Among them, C Cell is the specific heat capacity of the battery cell, m Cell is the mass of the battery cell, and γ is the heat exchange efficiency between the coolant and the battery cell.

[0113] The temperature formula of the whole power battery pack is:

[0114]

[0115]

[0116] Among them, T max is the maximum temperature of the power battery, T min is the lowest temperature of the power battery, T avg is the average temperature of the power battery, n s is the number of power battery packs, n P Indicates the number of power batteries connected in parallel.

[0117] Finally, the power that the power battery can provide based on the temperature of the entire pack and the SOC prediction is compared with the predicted power battery power required by the entire vehicle. When the predicted power battery power required by the entire vehicle is met and the power battery temperature does not exceed the appropriate range, the power battery control strategy with the minimum required coolant heat transfer energy is selected and output to the relevant control party for execution.

[0118] The embodiment of the present application can obtain the response surface of the power battery for different power battery thresholds entering cooling, coolant flow rates and coolant temperatures under the predicted power battery power requirements according to the power battery thermal management control model, and finally obtain the matching combination of the power battery threshold, coolant flow rate and coolant temperature with the minimum required cooling amount, thereby ensuring that the power battery is within a reasonable range while avoiding affecting the driving of the entire vehicle, and reducing the cooling energy consumption required for the thermal management of the power battery.

[0119] The present application is described in detail below with reference to a specific embodiment.

[0120] Figure 2 This is a flow chart of a thermal management method for a power battery according to an embodiment of the present application. Figure 2 As shown:

[0121] Step S201, obtaining road conditions and vehicle information: The vehicle map system can obtain the current driving route of the user's vehicle, such as the road conditions from point A to point B, such as distance, slope, traffic lights, congestion, etc., and the vehicle information such as vehicle drag coefficient, vehicle mass, power transmission efficiency and tire information, etc., and then predict the wheel-end power of the whole vehicle according to the road conditions and vehicle information, and predict the required power battery power of the whole vehicle according to the wheel-end power and power transmission efficiency;

[0122] Step S202, obtaining the current power battery status: mainly obtaining the SOC, voltage, temperature and available power of the current power battery;

[0123] Step S203, obtaining the current cooling state of the power battery, such as the current water inlet temperature, water outlet temperature and water inlet flow rate of the power battery cooling system;

[0124] Step S204, constructing a power battery thermal management control model;

[0125] Step S205, obtaining the most energy-efficient power battery thermal management control strategy using a power battery thermal management control model according to the current power battery state, the current cooling state and the predicted power battery power;

[0126] Step S206, predicting the power battery state: using the power battery thermal management control model to predict the power battery state change process;

[0127] Step S207, determining whether the power battery temperature requirement and the vehicle power requirement are met;

[0128] Step S208: if the power battery temperature requirement and the vehicle power requirement are met, further determine whether the cooling power requirement is the minimum at this time. If it is the minimum, proceed to the next step; otherwise, return to step S204;

[0129] Step S209, power battery thermal management execution: output the most energy-saving power battery thermal management control strategy to the relevant control party for execution, wherein steps S201 to S208 are repeatedly executed every 1 minute.

[0130] According to the thermal management method of the power battery proposed in the embodiment of the present application, the wheel-end power of the vehicle and the power battery power required by the vehicle can be predicted, and the thermal management control action that meets the preset energy-saving conditions is generated and executed in combination with the current power battery state and the current cooling state of the power battery. Thus, the power demand of the vehicle and the power battery power required by the vehicle are predicted according to the vehicle's driving road information, vehicle information, driving habits, power transmission efficiency, etc., avoiding the lag between the generation and actual execution of the thermal management strategy. Through the power battery thermal management control model, the power battery SOC, temperature and other related power battery information are quickly predicted and calculated, and different power battery thermal management control strategies are generated to achieve the power battery within a reasonable range without affecting the driving of the vehicle, and the cooling energy consumption required for the thermal management of the power battery can be effectively reduced, and the thermal management requirements of the vehicle can be met simply and effectively. Thus, the problem of certain lag and redundancy in the thermal management of the power battery in the related art is solved. When the cooling is entered late or the subsequent power battery power is large / small, the power battery power may decrease and affect the driving of the vehicle, or cause waste of cooling, and the control of the power battery thermal management cannot be realized in a timely and accurate manner, affecting the vehicle's power battery range.

[0131] Next, the battery management system proposed according to the embodiment of the present application is described with reference to the accompanying drawings.

[0132] Figure 3 It is a structural diagram of a battery management system according to an embodiment of the present application.

[0133] like Figure 3 As shown, the battery management system 10 includes: a first prediction module 100 , a second prediction module 200 and a management module 300 .

[0134] The first prediction module 100 is used to predict the entire wheel-end power of the vehicle when the vehicle is in a thermal management condition.

[0135] The second prediction module 200 is used to predict the vehicle's required power battery power according to the vehicle's wheel-end power and the power transmission efficiency of the power battery.

[0136] The management module 300 is used to generate a thermal management control action for the power battery that meets preset energy-saving conditions according to the current power battery state and current cooling state of the power battery and the power battery power required by the whole vehicle, and control the vehicle to execute the thermal management control action.

[0137] Optionally, in one embodiment of the present application, the first prediction module 100 includes: an acquisition unit and a prediction unit.

[0138] The acquisition unit is used to acquire the road information for traveling to the target location and acquire the whole vehicle information of the vehicle.

[0139] The prediction unit is used to predict the vehicle's entire wheel-end power based on road information and vehicle information.

[0140] Optionally, in one embodiment of the present application, the acquisition unit includes: a first acquisition subunit.

[0141] The first acquisition subunit is used to acquire at least one of the distance, slope, traffic light information, and traffic information between the starting point and the target location as road information.

[0142] Optionally, in one embodiment of the present application, the acquisition unit further includes: a second acquisition subunit and a generation subunit.

[0143] The second acquisition subunit is used to obtain the vehicle drag coefficient and mass of the vehicle and identify the user's driving habits.

[0144] The generation subunit is used to generate vehicle information based on the vehicle's drag coefficient, mass and driving habits.

[0145] Optionally, in one embodiment of the present application, it further includes: a detection module and a third prediction module.

[0146] Among them, the detection module is used to detect whether the preset management conditions are met at the current moment before predicting the vehicle's entire wheel-end power.

[0147] The third prediction module is used to start predicting the entire wheel end power when the preset management conditions are met.

[0148] Optionally, in one embodiment of the present application, the management module 300 includes: an input unit and a generation unit.

[0149] Among them, the input unit is used to input the current power battery status, the current cooling status, and the power battery power required by the whole vehicle into a pre-built power battery thermal management control model to obtain the power battery target value, coolant flow rate and coolant temperature that meet the preset energy-saving conditions.

[0150] The generating unit is used to generate a thermal management control action based on the power battery target value, the coolant flow rate and the coolant temperature.

[0151] It should be noted that the above explanation of the embodiment of the thermal management method for a power battery is also applicable to the battery management system of this embodiment and will not be repeated here.

[0152] According to the battery management system proposed in the embodiment of the present application, the vehicle's wheel-end power and the vehicle's required power battery power can be predicted, and the thermal management control action that meets the preset energy-saving conditions is generated and executed in combination with the current power battery state and the current cooling state of the power battery. Thus, the vehicle's driving power demand and the vehicle's required power battery power are predicted based on the vehicle's driving road information, vehicle information, driving habits, power transmission efficiency, etc., avoiding the lag between the generation and actual execution of thermal management strategies. Through the power battery thermal management control model, the power battery SOC, temperature and other related power battery information are quickly predicted and calculated, and different power battery thermal management control strategies are generated to ensure that the power battery is within a reasonable range without affecting the driving of the vehicle, and the cooling energy consumption required for the power battery thermal management can be effectively reduced, and the vehicle's thermal management requirements can be met simply and effectively. Thus, the problem of certain lag and redundancy in the thermal management of power batteries in the related art is solved. When the cooling is entered later or the subsequent power battery power is larger / smaller, the power battery power may decrease and affect the driving of the vehicle, or cause a waste of cooling, and the power battery thermal management control cannot be realized in a timely and accurate manner, affecting the vehicle's power battery range.

[0153] Figure 4 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application. The vehicle may include:

[0154] Memory 401 , processor 402 , and a computer program stored in the memory 401 and executable on the processor 402 .

[0155] When the processor 402 executes the program, the thermal management method of the power battery provided in the above embodiment is implemented.

[0156] Furthermore, the vehicle also includes:

[0157] The communication interface 403 is used for communication between the memory 401 and the processor 402 .

[0158] The memory 401 is used to store computer programs that can be executed on the processor 402 .

[0159] The memory 401 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0160] If the memory 401, the processor 402 and the communication interface 403 are implemented independently, the communication interface 403, the memory 401 and the processor 402 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0161] Optionally, in a specific implementation, if the memory 401, the processor 402 and the communication interface 403 are integrated on a chip, the memory 401, the processor 402 and the communication interface 403 can communicate with each other through an internal interface.

[0162] The processor 402 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.

[0163] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned thermal management method for a power battery.

[0164] An embodiment of the present application also provides a computer program product, including a computer program, which can run computer instructions. When the computer instructions are executed by a processor, the thermal management method of the power battery provided in the embodiment of the present application is implemented.

[0165] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0166] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0167] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0168] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0169] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0170] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0171] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, 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. If 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.

[0172] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, 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 cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A thermal management method for a power battery, characterized in that: The following steps are involved: When the vehicle is in a thermal management condition, predicting the total wheel-end power of the vehicle; Predicting the vehicle required power battery power of the vehicle according to the wheel-end power and the power transmission efficiency of the power battery; A thermal management control action for the power battery that meets preset energy-saving conditions is generated according to the current power battery state and the current cooling state of the power battery and the power battery power required by the entire vehicle, and the vehicle is controlled to execute the thermal management control action.

2. The method according to claim 1, characterized in that: The predicting of the entire wheel-end power of the vehicle comprises: Obtaining road information for traveling to a target location and obtaining vehicle information of the vehicle; The entire wheel-end power of the vehicle is predicted based on the road information and the entire vehicle information.

3. The method according to claim 2, characterized in that The step of obtaining the road information to the target location includes: At least one of the distance, slope, traffic light information, and traffic information between the starting point and the target location is obtained as the road information.

4. The method according to claim 2, characterized in that: The obtaining of the vehicle information includes: Obtaining a vehicle drag coefficient and a mass of the vehicle, and identifying a user's driving habits; The whole vehicle information is generated according to the vehicle drag coefficient, the mass and the driving habit.

5. The method according to claim 1, characterized in that Before predicting the full wheel-end power of the vehicle, the method further includes: Check whether the preset management conditions are met at the current moment; When the preset management conditions are met, the entire wheel end power is predicted.

6. The method according to claim 1, characterized in that The generating of the thermal management control action of the power battery that meets the preset energy-saving condition according to the current power battery state and the current cooling state of the power battery and the power battery power required by the whole vehicle includes: Inputting the current power battery state, the current cooling state, and the required power battery power of the whole vehicle into a pre-built power battery thermal management control model to obtain a power battery target value, coolant flow rate, and coolant temperature that meet the preset energy-saving conditions; The thermal management control action is generated based on the power battery target value, the coolant flow rate, and the coolant temperature.

7. A battery management system, characterized in that: include: A first prediction module, used for predicting the whole wheel end power of the vehicle when the vehicle is in a thermal management condition; A second prediction module is used to predict the whole vehicle required power battery power of the vehicle according to the whole wheel end power and the power transmission efficiency of the power battery; A management module is used to generate a thermal management control action for the power battery that meets preset energy-saving conditions according to the current power battery state and the current cooling state of the power battery and the power battery power required by the whole vehicle, and control the vehicle to execute the thermal management control action.

8. A vehicle, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the thermal management method for a power battery according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the thermal management method for a power battery as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed, it is used to implement the thermal management method of the power battery according to any one of claims 1 to 6.

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