Heating control method, vehicle and storage medium

Abstract

The invention provides a heating control method for a battery, a vehicle and a storage medium, and the method comprises the steps: when the environment temperature of the vehicle is lower than a preset environment temperature threshold value, if the vehicle is detected to enter a working state, obtaining ohm characteristic data and operation monitoring data of the battery in the vehicle; based on the ohm characteristic data, the operation monitoring data and preset voltage limiting data, pulse current and pulse frequency used for heating the battery are determined, and the pulse current comprises charging pulse current and discharging pulse current; and controlling the charging pulse current and the discharging pulse current to alternately electrically heat the battery based on the pulse frequency. According to the scheme, the adverse effect on the service life of the battery is avoided while the heating efficiency of the battery is ensured.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to a battery heating control method, a vehicle and a storage medium. Background Art

[0002] Since the performance of the battery will drop significantly in a low temperature environment, the related technology often uses a fixed large current pulse to heat the battery in a low temperature state when using AC pulse heating. However, using a large current pulse to heat the battery in a low temperature environment can easily shorten the battery life. Therefore, how to reasonably adjust the current pulse amplitude and frequency to ensure the heating efficiency of the battery without affecting the battery life has become a technical problem that needs to be solved urgently. Summary of the invention

[0003] The present application provides a battery heating control method, a vehicle and a storage medium, aiming to optimize the battery heating process and thereby increase the battery life.

[0004] In a first aspect, the present application provides a battery heating control method, which is applied to a vehicle. The heating control method includes:

[0005] When the ambient temperature of the vehicle is lower than a preset ambient temperature threshold, if it is detected that the vehicle enters a working state, the ohmic characteristic data and operation monitoring data of the battery in the vehicle are obtained;

[0006] Determine a pulse current and a pulse frequency for heating the battery based on the ohmic characteristic data, the operation monitoring data and the preset voltage limit data, wherein the pulse current includes a charging pulse current and a discharging pulse current;

[0007] The charging pulse current and the discharging pulse current are alternately controlled based on the pulse frequency to electrically heat the battery.

[0008] In some embodiments of the present application, obtaining ohmic characteristic data and operation monitoring data of a battery in a vehicle includes:

[0009] Sending a preset test pulse current to the battery based on a pulse current generator in the vehicle to obtain an ohmic voltage drop and an ohmic voltage drop time of the battery;

[0010] Determine the ohmic internal resistance of the battery based on the ohmic voltage drop and the test pulse current;

[0011] The ohmic internal resistance, ohmic voltage drop and ohmic voltage drop time are integrated to generate ohmic characteristic data.

[0012] In some embodiments of the present application, the operation monitoring data includes the battery temperature, the remaining power, and the battery voltage of the battery. Acquiring the ohmic characteristic data and the operation monitoring data of the battery in the vehicle includes:

[0013] Obtaining a battery surface temperature of the battery, wherein the battery surface temperature is a temperature collected by a battery temperature sensor;

[0014] The battery surface temperature is input into a preset electrothermal coupling model to obtain the battery internal temperature corresponding to the battery surface temperature, and the battery internal temperature is used to determine the battery temperature.

[0015] In some embodiments of the present application, based on the ohmic characteristic data, the operation monitoring data and the preset voltage limit data, determining the pulse current and pulse frequency for heating the battery includes:

[0016] Extract the battery's ohmic internal resistance, ohmic voltage drop, and ohmic voltage drop time from the ohmic characteristic data;

[0017] determining a target voltage threshold from the voltage limit data, and determining a pulse current based on the target voltage threshold, the ohmic internal resistance, and the battery voltage;

[0018] The pulse frequency is determined based on the ohmic voltage drop time.

[0019] In some embodiments of the present application, determining a target voltage threshold from voltage limit data, and determining a pulse current based on the target voltage threshold, the ohmic internal resistance, and the battery voltage includes:

[0020] determining a pulse charging voltage threshold in the voltage limit data as a first target voltage threshold;

[0021] The charging pulse current is determined based on the first target voltage threshold, the ohmic internal resistance, and the battery voltage.

[0022] In some embodiments of the present application, determining a target voltage threshold from voltage limit data, and determining a charging pulse current based on the target voltage threshold, the ohmic internal resistance, and the battery voltage includes:

[0023] determining a pulse discharge voltage threshold in the voltage limit data as a second target voltage threshold;

[0024] The discharge pulse current is determined based on the second target voltage threshold, the ohmic internal resistance, and the battery voltage.

[0025] In some embodiments of the present application, after the charging pulse current and the discharging pulse current are alternately controlled based on the pulse frequency to electrically heat the battery, the method further includes:

[0026] Obtaining a temperature change value of the battery based on a preset interval duration;

[0027] If the temperature change value is equal to the preset temperature threshold, the electric heating of the battery is stopped.

[0028] In some embodiments of the present application, the method further comprises:

[0029] If it is detected that the battery temperature and / or the remaining power of the battery change, the steps of determining the pulse current and pulse frequency for heating the battery, and controlling the charging pulse current and the discharging pulse current to alternately electrically heat the battery based on the pulse frequency are executed.

[0030] In a second aspect, the present application provides a vehicle, the vehicle comprising:

[0031] A memory for storing executable program codes;

[0032] The processor is used to call and run the executable program code from the memory so that the vehicle executes the steps of the above battery heating control method.

[0033] In a third aspect, the present application provides a computer-readable storage medium, which stores computer program code. When the computer program runs on a computer, the steps of the above-mentioned battery heating control method are implemented.

[0034] The beneficial effects brought about by the technical solutions provided in some embodiments of the present application include at least: by obtaining the ohmic characteristic data and operation monitoring data of the battery, it is possible to accurately adapt to the characteristic requirements of the battery in different low-temperature environments, avoiding overheating or insufficient heating. Precision heating helps to improve the performance of the battery at low temperatures, reduce the battery capacity attenuation caused by low temperatures, and thus extend the service life of the battery. Secondly, the alternating heating method of charging pulse current and discharging pulse current is more efficient and energy-saving than the traditional single heating method, ensuring the battery heating efficiency while avoiding adverse effects on the battery life. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 This is a schematic diagram of the first structure of the heating control method provided in the embodiment of the present application;

[0037] Figure 2 This is a first flow chart of the heating control method provided in the embodiment of the present application;

[0038] Figure 3 It is a second flow chart of the heating control method provided in the embodiment of the present application;

[0039] Figure 4 This is a third flow chart of the heating control method provided in the embodiment of the present application;

[0040] Figure 5 This is a fourth flow chart of the heating control method provided in the embodiment of the present application;

[0041] Figure 6 This is a fifth flow chart of the heating control method provided in the embodiment of the present application;

[0042] Figure 7 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to make the features and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0044] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0045] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0046] In the related art, vehicles generally use natural heating to heat the battery. During driving, the battery temperature is gradually increased based on the heat generated by the battery itself and the heat transferred from the surrounding environment.

[0047] However, this natural heating method has certain defects. On the one hand, the heating efficiency is relatively low. Especially in low-temperature environments, the heat generated by the natural operation of the vehicle alone is far from enough for the battery to quickly reach the ideal operating temperature range, which will lead to limited battery performance, such as reduced charging and discharging efficiency and greatly reduced driving range. On the other hand, the natural heating process is difficult to control accurately, and it is impossible to make timely and effective temperature adjustments according to the actual temperature requirements of the battery, which will cause the battery to be in an unsuitable temperature state for a long time, thereby affecting the battery's service life.

[0048] In order to solve the problems in the related art, the embodiments of the present application provide a battery heating control method, which is described in detail below. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments.

[0049] In order to improve the service life of the battery, the embodiment of the present application provides a battery heating control method, and the execution subject of the battery heating control method can be a vehicle. The following are detailed descriptions respectively. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments.

[0050] See also Figure 1 , Figure 1 Schematic diagram of a battery heating control method provided in an embodiment of the present application. Figure 1 As shown, the execution modules in this solution include but are not limited to batteries, battery management modules, and pulse signal generators.

[0051] Batteries are used to store chemical energy and convert it into electrical energy, providing power support for various electrical devices during vehicle operation.

[0052] The battery management module is equipped with a battery management system (BMS) to monitor the key parameters of the battery in real time, such as voltage, current, battery temperature, etc. The battery management module has a built-in preset intervention algorithm, which is used to ensure that the battery always operates within a safe and efficient range. It also has functions such as battery status estimation and balancing management to extend battery life and optimize overall performance.

[0053] The pulse signal generator is used to generate a pulse signal of specific frequency and amplitude according to the control signal of the battery management module, which is used to control battery heating or other related operations. The pulse signal it generates can achieve detailed regulation of the battery heating process to achieve the purpose of heating the battery and ensure that the battery operates at the optimal temperature.

[0054] In actual application scenarios, when the vehicle changes from a parking state to a working state, the pulse signal generator starts to work under the control of the battery management module. The pulse signal generator applies a test pulse current to the battery.

[0055] When the test pulse current is applied to the battery, an ohmic voltage drop will immediately occur at both ends of the battery due to the existence of the battery's internal resistance. The battery management module uses voltage and current sensors to collect the voltage changes at both ends of the battery and the current data flowing through the battery to determine the battery's ohmic voltage drop.

[0056] The voltage curve will change due to factors such as the polarization effect of the battery. The battery management module monitors the ohmic voltage drop caused by the internal voltage drop of the battery from the start of the test pulse current application. The battery management module analyzes the collected voltage and time data to determine the time point when the voltage transitions from the initial ohmic voltage drop rapid change stage to the change stage affected by the polarization effect, that is, the time it takes for the test pulse current to start passing into the battery and the voltage drop in the battery to completely stabilize, and this is recorded as the ohmic voltage drop time. Substitute the ohmic voltage drop and the measured pulse current into the Ohm's law formula to determine the ohmic internal resistance of the battery.

[0057] Repeat the above test pulse current application, data collection and analysis process under different temperature and remaining power conditions. By measuring at multiple different temperatures, the ohmic internal resistance, ohmic voltage drop and ohmic voltage drop completion time of the battery under various working conditions can be obtained.

[0058] Furthermore, based on the battery management module, the operation monitoring data of the battery is obtained, and the voltage limit data preset in the battery management module is obtained, wherein the operation monitoring data includes the battery temperature, the remaining power and the battery voltage of the battery, and the voltage limit data includes the pulse charging voltage threshold and the pulse discharging voltage threshold used for pulse heating of the battery. The pulse charging voltage threshold refers to the maximum voltage limit that the battery can withstand during the pulse charging process, and the pulse discharge voltage threshold is the minimum limit to which the battery voltage can be allowed to drop under the pulse discharge operation.

[0059] Substituting the above-obtained ohmic internal resistance, battery voltage and pulse charging voltage threshold into the preset maximum charging current calculation formula can obtain the discharge pulse current. At the same time, substituting the above-obtained ohmic internal resistance, battery voltage and pulse discharge voltage threshold into the preset maximum discharge current calculation formula can obtain the discharge pulse current. The number of times the pulse current is applied to the battery per second is determined based on the ohmic voltage drop time, that is, the pulse frequency, wherein the pulse frequency is a parameter used to measure the number of current pulse changes per unit time when the battery is operated with a pulse current, that is, the time required for a complete cycle when the pulse current sends a change.

[0060] Exemplarily, the discharge pulse current is 964A, the discharge pulse current is 1660A, and the pulse frequency is 100Hz, which means that the current direction is switched every 0.01 seconds. Assuming that the battery is in a low temperature state at this moment, the battery management module begins to charge the battery by controlling the pulse signal generator to generate a discharge pulse current of 964A, which lasts for 0.01 seconds. During the 0.01 second period, the current passes through the battery to generate heat, causing the battery temperature to begin to rise. After 0.01 seconds, the battery management module controls the current direction to switch. At this time, the battery enters the discharge state and controls the battery to generate a discharge pulse current of 1664A for discharge, which also lasts for 0.0.1 seconds. During the discharge process, the battery continues to generate heat due to the passage of current, further increasing the battery temperature.

[0061] Repeat the above heating steps to control the working state of the battery to switch back and forth between charging and discharging, and repeat the operation in this way. After a period of time, if the battery temperature of the battery reaches the target temperature, the heating of the battery is stopped.

[0062] It should be noted that during the heating process, it is necessary to monitor the changes in the battery voltage and / or remaining power of the battery in real time. Once the change in the battery voltage and / or remaining power is detected to be greater than or equal to a preset change threshold, the above-mentioned entire execution process needs to be repeated to ensure that the charging pulse current and discharging pulse current for heating the battery are of optimal current size.

[0063] based on Figure 1 The system architecture diagram shown below will be combined with Figure 2-Figure 6 , a battery heating control method provided in an embodiment of the present application is introduced in detail.

[0064] See also Figure 2 , Figure 2 1 is a schematic diagram of a first flow chart of a battery heating control method provided in an embodiment of the present application. Figure 2 As shown, the method of the embodiment of the present application may include the following S101-S103.

[0065] S101, when the ambient temperature of the vehicle is lower than a preset ambient temperature threshold, if it is detected that the vehicle enters a working state, then ohmic characteristic data and operation monitoring data of a battery in the vehicle are obtained.

[0066] In the embodiment of the present application, the ambient temperature of the vehicle has a crucial impact on the battery performance. Different batteries have their suitable operating temperature ranges. When the ambient temperature is too low, the various performance indicators of the battery cannot reach the optimal state. Therefore, it is necessary to pre-set an ambient temperature threshold, where the ambient temperature threshold is determined based on factors such as the battery type and the normal operation requirements of the vehicle, and is not specifically limited here.

[0067] Specifically, when the ambient temperature of the vehicle is lower than the preset ambient temperature threshold and the vehicle enters the working state, the pulse current generator equipped in the vehicle is enabled through the power management module, wherein the pulse current generator can send a specific test pulse current to the battery according to the pre-set relevant parameters. The size of the test pulse current is set in the actual experimental environment and is not specifically limited here. When the test pulse current flows through the battery, due to the internal resistance of the battery itself, the current passing through the internal resistance will cause the voltage at both ends of the positive and negative electrodes of the battery to change. At this time, the ohmic voltage drop of the battery is obtained in real time through the corresponding voltage detection device in the vehicle.

[0068] At the same time, the timing starts from the moment the test pulse current starts to flow into the battery. Due to the ohmic internal resistance inside the battery, the test pulse current will produce a voltage drop time when passing through the internal resistance. The time taken from the start of the test pulse current to the complete establishment of a stable voltage drop is recorded as the ohmic voltage drop time.

[0069] According to Ohm's law, R = V / I (resistance equals voltage divided by current), where V is voltage and I is current. The ohmic voltage drop obtained above is regarded as the voltage in the formula, and the test pulse current sent is regarded as the current. Through the calculation, the ohmic internal resistance R of the battery can be determined. Ω . The timing starts from the moment the test pulse current starts to flow into the battery. Due to the ohmic internal resistance inside the battery, the test pulse current will generate a voltage drop when passing through the internal resistance. The time T taken from the start of the test pulse current to the complete establishment of a stable voltage drop is detected and determined, and T is used as the ohmic voltage drop. The ohmic internal resistance, ohmic voltage drop, and ohmic voltage drop time are integrated to obtain the ohmic characteristic data.

[0070] Furthermore, the battery voltage is collected through a voltage sensor, which can sense the potential difference between the positive and negative terminals of the battery in real time, and convert the potential difference into an electrical signal, and then the analog electrical signal is converted into a digital signal through the built-in analog-to-digital conversion module to obtain the battery voltage. On the other hand, through the power calculation algorithm in the battery management module, the current charging and discharging current, discharge time, and rated capacity of the battery are obtained in real time through the current sensor installed in the battery circuit, and the remaining power of the battery is determined by performing integral operations according to the preset power calculation model. On the other hand, the battery temperature sensor is reasonably arranged at the preset position of the battery. The battery temperature sensor will cause the physical properties of its own thermistor to change according to the change of battery temperature, thereby generating different electrical signals, and generating the battery temperature after signal processing. By integrating the battery voltage, remaining power, and battery temperature, operation monitoring data is generated.

[0071] S102 : Determine a pulse current and a pulse frequency for heating the battery based on the ohmic characteristic data, the operation monitoring data, and the preset voltage limit data.

[0072] In the embodiment of the present application, the voltage limit data includes a pulse charging voltage threshold and a pulse discharging voltage threshold for pulse current heating of the battery. The pulse charging voltage threshold refers to the maximum voltage limit that the battery can withstand during the pulse charging process, and the pulse discharging voltage threshold refers to the minimum limit to which the battery voltage can be allowed to drop under the pulse discharging operation.

[0073] Specifically, the ohmic internal resistance, battery voltage and pulse charging voltage threshold in the ohmic characteristic data in S101 are substituted into the preset maximum charging current calculation formula to obtain the discharge pulse current. The ohmic internal resistance, battery voltage and pulse discharge voltage threshold obtained above are substituted into the preset maximum discharge current calculation formula to obtain the discharge pulse current.

[0074] The ohmic voltage drop time obtained in the above S101 is substituted into a preset pulse frequency calculation formula to obtain the pulse frequency, wherein the pulse frequency represents the time interval for controlling the pulse current to switch.

[0075] S103, controlling the charging pulse current and the discharging pulse current based on the pulse frequency to electrically heat the battery alternately.

[0076] Specifically, the charging pulse current path is turned on to heat the battery. At the same time, the battery management module performs heating timing according to the pulse frequency obtained according to the above S102. After one pulse frequency, the charging pulse current path is quickly cut off, and the discharge pulse current path is turned on at the same time to allow the discharge pulse current to flow into the battery. After continuing the same pulse frequency, it is switched back to the charging pulse current to ensure that the charging pulse current and the discharge pulse current can heat the battery alternately in a stable and orderly manner.

[0077] From the above, it can be seen that by obtaining the battery's ohmic characteristic data and operation monitoring data, it is possible to accurately adapt to the battery's characteristic requirements in different low-temperature environments and avoid overheating or underheating. Precision heating helps to improve the performance of the battery at low temperatures and reduce the battery capacity attenuation caused by low temperatures, thereby extending the battery's service life. Secondly, the alternating heating method of charging pulse current and discharging pulse current is more efficient and energy-saving than the traditional single heating method, ensuring the battery heating efficiency while avoiding adverse effects on the battery's service life.

[0078] When using pulse current to heat the battery, the current needs to be switched alternately. If the current is too large or too small, the heating effect will be affected. Therefore, it is necessary to improve the calculation accuracy of each pulse current. Figure 3 , Figure 3 FIG. 1 is a flow chart of a battery heating control method provided in an embodiment of the present application. Figure 3 As shown, the method of the embodiment of the present application may include the following S201-S203.

[0079] S201, sending a preset test pulse current to a battery based on a pulse current generator in the vehicle to obtain an ohmic voltage drop and an ohmic voltage drop time of the battery.

[0080] Specifically, in the battery management module of the vehicle, a pulse current generator equipped in the vehicle is enabled. This pulse current generator can send a specific test pulse current to the battery according to pre-set relevant parameters. The size of the test pulse current is set in the actual experimental environment and is not specifically limited here.

[0081] When the test pulse current flows through the battery, the voltage at the positive and negative terminals of the battery will change due to the internal resistance of the battery. At this time, the ohmic voltage drop of the battery is obtained in real time through the corresponding voltage detection device in the vehicle (usually a high-precision voltmeter or voltage sensor, etc.).

[0082] At the same time, the time is counted from the moment the test pulse current starts to flow into the battery. Due to the ohmic internal resistance inside the battery, the test pulse current will produce a voltage drop time when passing through the internal resistance. After measurement, it is found that the time T spent from the beginning of the test pulse current to the complete establishment of the voltage drop is 0.01 seconds. In other words, during this 0.01 second, the voltage across the battery gradually reaches the 10V ohmic voltage drop value we calculated earlier because the current passes through the internal resistance, and the value corresponding to T is determined as the ohmic voltage drop time.

[0083] S202, determining the ohmic internal resistance of the battery based on the ohmic voltage drop and the test pulse current.

[0084] Specifically, after the ohmic voltage drop is obtained, according to Ohm's law R=V / I, where I is the test pulse current and V represents the ohmic voltage drop, the ohmic internal resistance of the battery can be accurately calculated by dividing the ohmic voltage drop by the test pulse current.

[0085] For example, the test pulse current size I is 2A (ampere), and the ohmic voltage drop is 1V. According to Ohm's law, the ohmic internal resistance is

[0086] S203, integrating the ohmic internal resistance, the ohmic voltage drop and the ohmic voltage drop time to generate ohmic characteristic data.

[0087] Specifically, the ohmic internal resistance, ohmic voltage drop and ohmic voltage drop time obtained in the above S201-S202 are integrated to form ohmic characteristic data and transmitted to the battery management module for data storage.

[0088] From the above, we can see that by sending a test pulse current to the battery to obtain the ohmic voltage drop and ohmic voltage drop time, the instantaneous reaction of the battery under the action of current can be accurately grasped in a non-destructive way. Next, the ohmic internal resistance is calculated based on the ohmic voltage drop and the test pulse current, which can provide an in-depth understanding of the internal resistance of the battery to the current and the corresponding voltage changes, and the energy loss, heat generation, etc. Finally, the ohmic internal resistance, ohmic voltage drop, and ohmic voltage drop time are integrated to generate ohmic characteristic data, which can be easily called at any time in battery management. This series of operations is conducive to the reasonable formulation of charging and discharging strategies to avoid overcharging and over-discharging of batteries. It can also optimize pulse heating and other operations to ensure stable battery performance and extend service life.

[0089] Due to the difference between the surface temperature of the battery and the internal temperature of the battery, conventional temperature sensors cannot accurately measure the temperature inside the battery cell, and thus cannot accurately control the subsequent heating control process. Figure 4 , Figure 4 is a general flow chart of a battery heating control method provided in an embodiment of the present application. Figure 4 As shown, the method of the embodiment of the present application may include the following S301-S302.

[0090] S301, obtaining a battery surface temperature of a battery, wherein the battery surface temperature is a temperature collected by a battery temperature sensor.

[0091] In the embodiment of the present application, the battery temperature sensor has a specific installation layout in the battery, and is usually placed at a key position on the battery surface to accurately and comprehensively reflect the temperature of the battery as a whole. For example, for a rectangular battery module, the sensor may be distributed on the top, bottom and side of the module to ensure that the temperature information of different parts can be captured to avoid the omission of local temperature monitoring.

[0092] Specifically, when the battery is in working condition, the battery temperature sensor senses the temperature change on the battery surface through its own thermistor characteristics. The thermistor will undergo physical phenomena such as resistance change (for thermistor type sensor) or potential change (for thermocouple type sensor) as the battery surface temperature changes, and then convert the physical quantity of temperature into an electrical signal. Subsequently, the built-in signal processing circuit of the battery temperature sensor will perform preliminary processing such as amplification and filtering on the electrical signal, making it a standard electrical signal form that can be accurately identified and read subsequently, thus completing the collection of battery surface temperature data.

[0093] The processed temperature data will be transmitted to the battery management module connected thereto via wired or wireless communication. After the relevant data receiving module of the battery management module receives the temperature data from the temperature sensor, the battery surface temperature execution process of obtaining the battery is completed.

[0094] S302, inputting the battery surface temperature into a preset electrothermal coupling model to obtain the battery internal temperature corresponding to the battery surface temperature, and determining the battery temperature using the battery internal temperature.

[0095] It should be noted that the electrothermal coupling model is a model that has been trained and has reached a convergence state. During the electrothermal coupling model training phase, technicians will build an electrothermal coupling model suitable for the battery type based on the battery's electrochemical and thermal properties as well as a large amount of experimental data and theoretical analysis.

[0096] The model comprehensively considers the heat generation mechanisms such as heat generated by electrochemical reactions during the battery's charge and discharge process, heat generated by current through internal resistance, as well as heat transfer processes such as heat conduction, heat convection inside the battery, and heat exchange with the external environment. It describes the battery's electrothermal coupling relationship through a series of mathematical equations (such as the common heat balance equation based on the law of conservation of energy, etc.). In addition, before actual application, the model will be repeatedly calibrated and verified to ensure that it can accurately output reliable battery internal temperature results based on different input parameters (such as the battery surface temperature here), that is, an accurate and available electrothermal coupling model has been preset and is waiting for data input.

[0097] Specifically, after the battery surface temperature data is obtained based on the above S301, the battery surface temperature value will be passed as an input parameter to the preset electrothermal coupling model. After receiving the battery surface temperature value, the electrothermal coupling model will perform a series of operations based on the internally set algorithm and mathematical equations, combined with other known battery-related parameters (such as the battery's internal resistance, heat capacity and other parameters, which are fixed values ​​obtained in advance through experiments or stored in the system according to the battery specification manual). For example, based on the surface temperature combined with the thermal conductivity coefficient and the internal structural characteristics of the battery, the heat transfer from the battery surface to the battery cell is calculated, and then the internal electrical heating factors of the battery are comprehensively considered to comprehensively determine the temperature of the battery cell position.

[0098] After the operation of the electrothermal coupling model, a battery internal temperature value corresponding to the input battery surface temperature will be output. Since the battery cell is the core part of the battery for electrochemical reaction, storage and release of electrical energy, its temperature has the most critical impact on the performance, life and safety of the battery, so the battery internal temperature calculated by the model is determined as the temperature of the entire battery. Subsequently, the battery management module will use the battery internal temperature as the battery temperature in the operation monitoring data.

[0099] From the above, we can see that after obtaining the battery surface temperature, it is input into the electrothermal coupling model to obtain the internal temperature of the battery and determine it as the battery temperature. This can accurately grasp the actual temperature of the battery cell, and troubleshoot hidden dangers caused by abnormal temperature in advance to ensure safety; it can also allow the battery management module to adjust the charging and discharging strategy accordingly, so that the battery is in a suitable temperature range and maintain good performance, thereby extending the battery life.

[0100] In order to further improve the current accuracy of each pulse current. Figure 5 , Figure 5 is a general flow chart of a battery heating control method provided in an embodiment of the present application. Figure 5 As shown, the method of the embodiment of the present application may include the following S401-S407.

[0101] S401, extracting the ohmic internal resistance, ohmic voltage drop and ohmic voltage drop time of the battery from the ohmic characteristic data.

[0102] Specifically, the process of obtaining the ohmic internal resistance, ohmic voltage drop and ohmic voltage drop time in S401 may refer to the above S201-S202, which will not be repeated here.

[0103] S402 , determining a target voltage threshold from the voltage limit data, and determining a pulse current based on the target voltage threshold, the ohmic internal resistance, and the battery voltage.

[0104] In the embodiment of the present application, the voltage limit data includes a pulse charging voltage threshold and a pulse discharging voltage threshold for pulse current heating of the battery. The pulse charging voltage threshold refers to the maximum voltage limit that the battery can withstand during the pulse charging process, and the pulse discharging voltage threshold refers to the minimum limit to which the battery voltage can be allowed to drop under the pulse discharging operation.

[0105] Substituting the above-obtained ohmic internal resistance, battery voltage and pulse charging voltage threshold into the preset maximum charging current calculation formula can obtain the discharge pulse current. Substituting the above-obtained ohmic internal resistance, battery voltage and pulse discharging voltage threshold into the preset maximum discharging current calculation formula can obtain the discharge pulse current.

[0106] S403, determining the pulse frequency based on the ohmic voltage drop time.

[0107] Specifically, the pulse frequency can be determined by substituting the ohmic voltage drop time into the preset pulse frequency calculation formula f=1 / T, wherein T is the ohmic voltage drop and f represents the pulse frequency.

[0108] Exemplarily, the ohmic voltage drop time T is 0.01 second (that is, the ohmic voltage drop stage lasts for 0.01 second). Substituting the time T into the preset pulse frequency calculation formula f=1 / T, we can get f=1 / 0.01=100Hz, which means that when the pulse current is used to operate this battery in the future, the pulse current needs to be switched 100 times per second, that is, the current direction needs to be switched once every 0.01 seconds.

[0109] S404: Determine the pulse charging voltage threshold in the voltage limit data as the first target voltage threshold.

[0110] S405 , determining a charging pulse current based on a first target voltage threshold, an ohmic internal resistance, and a battery voltage.

[0111] Specifically, in S404-S405, the above-obtained ohmic internal resistance, battery voltage and pulse charging voltage threshold are substituted into the preset maximum charging pulse current calculation formula Imax=(Umax-Ucell) / R Ω The discharge pulse current can be obtained, where Umax is the pulse charging voltage threshold, Ucell is the battery voltage obtained from the operation monitoring data at the current moment, and R Ω is the ohmic internal resistance.

[0112] For example, the battery voltage Ucell is 300V, the pulse discharge voltage threshold Umax is 400V, and the ohmic internal resistance R Ω 0.5m Ω , then according to the maximum charging pulse current calculation formula, we get (400-300) / 0.1=1000V / 0.5 Ω =960A, that is, the discharge pulse current is 960A.

[0113] S406: Determine the pulse discharge voltage threshold in the voltage limit data as the second target voltage threshold.

[0114] S407, determining a discharge pulse current based on the second target voltage threshold, the ohmic internal resistance and the battery voltage.

[0115] Specifically, in S406-S407, the ohmic internal resistance, battery voltage and pulse discharge voltage threshold obtained above are substituted into the preset maximum discharge pulse current calculation formula Imax=(Ucell-Umin) / R ΩThe discharge pulse current can be obtained, where Umin is the pulse discharge voltage threshold, Ucell is the battery voltage obtained from the operation monitoring data at the current moment, and R Ω is the ohmic internal resistance.

[0116] For example, the battery voltage Ucell is 200V, the pulse discharge voltage threshold Umax is 300V, and the ohmic internal resistance R Ω It is approximately equal to 0.6, then according to the maximum charging pulse current calculation formula, we get (200-300) / 0.1=1000V / 0.6 Ω =1660A, that is, the discharge pulse current is 1660A.

[0117] From the above, it can be seen that by extracting key parameters from the ohmic characteristic data and determining the target voltage threshold from the voltage limit data, the electrical characteristics of the battery itself and the voltage range for safe operation can be accurately grasped, providing data support for subsequent precise control. Then, based on these accurate data, the pulse current, charging pulse current and discharging pulse current can be determined, so that the current size of the battery can be adapted to the current condition of the battery during the pulse charging and discharging process. It can not only make full use of the current to generate heat through the ohmic internal resistance to effectively regulate the battery temperature, improve its ability to quickly reach a suitable operating temperature under different environments (especially low temperature environments), and ensure the stable performance of the battery, but also avoid damage to the battery caused by overcharging and over-discharging due to excessive current, and extend the battery life. And determining the pulse frequency based on the ohmic voltage drop can allow pulse charging and discharging to alternate at a reasonable rhythm, further optimize the efficiency and effect of battery heating and charging and discharging, ensure that the battery works efficiently under the premise of safety, and also provide strong support for the stable and reliable operation of the entire equipment using the battery.

[0118] To prevent the battery temperature from exceeding the optimal operating temperature. Figure 6 , Figure 6 is a flowchart of a battery heating control method provided in an embodiment of the present application. Figure 6 As shown, the method of the embodiment of the present application may include the following S501-S502.

[0119] S501, obtaining a temperature change value of a battery based on a preset interval duration.

[0120] In an embodiment of the present application, a fixed interval duration is pre-set in the battery management module. This duration is determined by comprehensively considering multiple factors such as the thermal response characteristics of the battery, monitoring accuracy requirements, and system computing resources, and is not specifically limited here.

[0121] Exemplarily, the preset interval duration is 1 second, and the battery management module enables a timing module to obtain the temperature change value of the battery once every one second according to the interval duration.

[0122] S502: If the temperature change value is equal to a preset temperature threshold, then stop electrically heating the battery.

[0123] In the embodiment of the present application, the preset temperature threshold is determined based on the optimal operating temperature range of the battery, the safety temperature limit, and a large number of past experiments and actual operating experience, and is not specifically limited here.

[0124] Exemplarily, the temperature threshold is 25 degrees, and the temperature change value is 20 degrees. Based on heating the battery, at a certain moment, the temperature change value obtained is 25 degrees, which is equal to the preset temperature threshold, and the heating of the battery is stopped.

[0125] From the above, we can see that through regular monitoring and threshold comparison, the battery can be effectively prevented from exceeding the appropriate temperature range due to overheating, and problems such as decomposition of internal battery chemicals and damage to the electrode structure can be avoided. The battery is always kept in a safe and efficient temperature range. At the same time, energy is used rationally, unnecessary waste of electric heating is avoided, the battery life is extended, and the stable operation of the entire battery-equipped equipment is guaranteed.

[0126] In a feasible implementation manner, the method of the embodiment of the present application may include the following execution steps:

[0127] If it is detected that the battery temperature and / or the remaining power of the battery change, the steps of determining the pulse current and pulse frequency for heating the battery, and controlling the charging pulse current and the discharging pulse current to alternately electrically heat the battery based on the pulse frequency are executed.

[0128] Specifically, when heating the vehicle battery, in order to ensure that the entire heating process is safe and efficient, it is necessary to pay real-time attention to the relevant status changes of the battery, that is, to monitor the battery voltage and remaining power (or one of the two) of the battery in real time.

[0129] During the heating period, the battery management module is based on a pre-set change threshold, which is a reasonable limit determined by comprehensively considering multiple factors such as battery performance and safety. Once it is found through monitoring that the change amplitude of the battery voltage and the change amplitude of the remaining power are greater than the corresponding change threshold, it indicates that the current charging pulse current or discharge pulse current is no longer suitable for the current state of the battery, which will cause the battery to be overcharged, over-discharged or other problems that affect battery performance and safety. At this time, it is necessary to restart the entire previously set execution process, re-determine relevant parameters such as ohmic internal resistance and ohmic voltage drop, and start from these basic data again. According to the new data, recalculate and determine the size of the charging pulse current and discharge pulse current suitable for the current battery state, so as to ensure that in the subsequent heating process, the charging pulse current and discharge pulse current applied to the battery are always optimal, so that the battery can be heated continuously and effectively under the premise of safety, maintain good performance and extend the battery life as much as possible.

[0130] See also Figure 7 , which is a schematic diagram of the structure of a vehicle provided in the embodiment of the present application. Figure 7 As shown, the vehicle 600 includes a processor 601 and a memory 602. The processor 601 is electrically connected to the memory 602.

[0131] The processor 601 is the control center of the vehicle 600 and may include one or more processing cores. The processor 601 uses various interfaces and lines to connect various parts of the entire vehicle, and executes various functions of the vehicle and processes data by running or calling computer programs stored in the memory 602, and calling data stored in the memory 602, so as to control the vehicle as a whole. Optionally, the processor 601 can be implemented in at least one hardware form of digital signal processing (DSP), field programmable gate array (FPGA), and programmable logic array (PLA). The processor 601 can integrate one or a combination of CPU, graphics processing unit (GPU), modem, etc. Among them, the CPU mainly processes the operating system, user pages, and applications; the GPU is responsible for rendering and drawing display content; and the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor 601, but may be implemented separately through a communication chip.

[0132] The memory 602 can be used to store software programs and modules, and the processor 601 executes various functional applications and data processing by running the computer programs and modules stored in the memory 602. The memory 602 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, a computer program required for at least one function, etc.; the data storage area can store data created according to the use of the vehicle, etc.

[0133] In addition, the memory 602 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage devices. Accordingly, the memory 602 may also include a memory controller to provide the processor 601 with access to the memory 602.

[0134] In the embodiment of the present application, the processor 601 in the vehicle 600 loads instructions corresponding to the processes of one or more computer programs into the memory 602 according to the following steps, and the processor 601 runs the computer program stored in the memory 602 to implement various functions, as follows:

[0135] When the ambient temperature of the vehicle is lower than a preset ambient temperature threshold, if it is detected that the vehicle enters a working state, the ohmic characteristic data and operation monitoring data of the battery in the vehicle are obtained;

[0136] Determine a pulse current and a pulse frequency for heating the battery based on the ohmic characteristic data, the operation monitoring data and the preset voltage limit data, wherein the pulse current includes a charging pulse current and a discharging pulse current;

[0137] The charging pulse current and the discharging pulse current are alternately controlled based on the pulse frequency to electrically heat the battery.

[0138] Optionally, when the processor 601 is executing to obtain the ohmic characteristic data and operation monitoring data of the battery in the vehicle, the following specifically executes: based on the pulse current generator in the vehicle, a preset test pulse current is sent to the battery to obtain the ohmic voltage drop and ohmic voltage drop time of the battery; based on the ohmic voltage drop and the test pulse current, the ohmic internal resistance of the battery is determined; and the ohmic internal resistance, ohmic voltage drop and ohmic voltage drop time are integrated to generate ohmic characteristic data.

[0139] Optionally, the processor 601 determines the pulse current and pulse frequency for heating the battery based on the ohmic characteristic data, the operation monitoring data and the preset voltage limit data, and specifically performs: extracting the ohmic internal resistance, ohmic voltage drop and ohmic voltage drop time of the battery from the ohmic characteristic data; determining the target voltage threshold from the voltage limit data, and determining the pulse current and pulse frequency based on the target voltage threshold, the ohmic internal resistance and the battery voltage, and determining the pulse frequency based on the ohmic voltage drop time.

[0140] Optionally, the processor 601 determines the target voltage threshold from the voltage limiting data, and determines the pulse current based on the target voltage threshold, the ohmic internal resistance and the battery voltage. Specifically, the processor 601 determines the pulse charging voltage threshold in the voltage limiting data as the first target voltage threshold; and determines the charging pulse current based on the first target voltage threshold, the ohmic internal resistance and the battery voltage.

[0141] Optionally, the processor 601 determines the target voltage threshold from the voltage limiting data, and determines the charging pulse current based on the target voltage threshold, the ohmic internal resistance and the battery voltage. Specifically, the processor 601 determines the pulse discharge voltage threshold in the voltage limiting data as the second target voltage threshold; and determines the discharge pulse current based on the second target voltage threshold, the ohmic internal resistance and the battery voltage.

[0142] Optionally, after executing the pulse frequency-based control of the charging pulse current and the discharging pulse current to alternately electrically heat the battery, the processor 601 specifically performs: obtaining the temperature change value of the battery based on a preset interval duration; if the temperature change value is equal to a preset temperature threshold, stopping electrically heating the battery.

[0143] Optionally, processor 601 is also used to specifically execute: if it is detected that the battery temperature and / or remaining power of the battery has changed, then determine the pulse current and pulse frequency for heating the battery, and control the charging pulse current and the discharging pulse current based on the pulse frequency to alternately electrically heat the battery.

[0144] In the embodiments of the present application, by obtaining the ohmic characteristic data and operation monitoring data of the battery, it is possible to accurately adapt to the characteristic requirements of the battery in different low temperature environments to avoid overheating or insufficient heating. Precision heating helps to improve the performance of the battery at low temperatures and reduce the battery capacity attenuation caused by low temperatures, thereby extending the service life of the battery. Secondly, the alternating heating method of charging pulse current and discharging pulse current is more efficient and energy-saving than the traditional single heating method, ensuring the battery heating efficiency while avoiding adverse effects on the battery service life.

[0145] A person of ordinary skill in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be completed by instructions, or by controlling related hardware through instructions. The instructions may be stored in a computer-readable storage medium and loaded and executed by a processor.

[0146] To this end, an embodiment of the present application provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is executed on a computer, the computer executes the above-mentioned related method steps to implement the steps of a battery heating control method provided in the above embodiment. For example, the following steps may be specifically executed:

[0147] When the ambient temperature of the vehicle is lower than a preset ambient temperature threshold, if it is detected that the vehicle enters a working state, the ohmic characteristic data and operation monitoring data of the battery in the vehicle are obtained;

[0148] Determine a pulse current and a pulse frequency for heating the battery based on the ohmic characteristic data, the operation monitoring data and the preset voltage limit data, wherein the pulse current includes a charging pulse current and a discharging pulse current;

[0149] The charging pulse current and the discharging pulse current are alternately controlled based on the pulse frequency to electrically heat the battery.

[0150] The storage medium may include: a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0151] Since the computer program code stored in the storage medium can execute the steps in any battery heating control method provided in the embodiments of the present application, the beneficial effects that can be achieved by any battery heating control method provided in the embodiments of the present application can be achieved. Please refer to the previous embodiments for details and will not be repeated here.

[0152] The above is a detailed introduction to a battery heating control method, a vehicle and a storage medium provided in an embodiment of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technicians in this field, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A battery heating control method, characterized in that: Applied to a vehicle, the heating control method comprises: When the ambient temperature of the vehicle is lower than a preset ambient temperature threshold, if it is detected that the vehicle enters a working state, obtaining ohmic characteristic data and operation monitoring data of a battery in the vehicle; Based on the ohmic characteristic data, the operation monitoring data and the preset voltage limit data, determining a pulse current and a pulse frequency for heating the battery, wherein the pulse current includes a charging pulse current and a discharging pulse current; The charging pulse current and the discharging pulse current are controlled based on the pulse frequency to alternately electrically heat the battery.

2. The heating control method according to claim 1, characterized in that: The obtaining of ohmic characteristic data and operation monitoring data of the battery in the vehicle, include:. Sending a preset test pulse current to the battery based on a pulse current generator in the vehicle to obtain an ohmic voltage drop and an ohmic voltage drop time of the battery; determining an ohmic internal resistance of the battery based on the ohmic voltage drop and the test pulse current; The ohmic internal resistance, the ohmic voltage drop and the ohmic voltage drop time are integrated to generate the ohmic characteristic data.

3. The heating control method according to claim 1, characterized in that: The operation monitoring data includes the battery temperature, the remaining power and the battery voltage of the battery, and the obtaining of the ohmic characteristic data and the operation monitoring data of the battery in the vehicle includes: Acquiring a battery surface temperature of the battery, wherein the battery surface temperature is a temperature collected by a battery temperature sensor; The battery surface temperature is input into a preset electrothermal coupling model to obtain the battery internal temperature corresponding to the battery surface temperature, and the battery temperature is determined by the battery internal temperature.

4. The heating control method according to claim 3, characterized in that: The step of determining a pulse current and a pulse frequency for heating the battery based on the ohmic characteristic data, the operation monitoring data, and preset voltage limit data includes: Extracting the ohmic internal resistance, ohmic voltage drop and ohmic voltage drop time of the battery from the ohmic characteristic data; determining the target voltage threshold from the voltage limit data, and determining the pulse current based on the target voltage threshold, the ohmic internal resistance, and the battery voltage; The pulse frequency is determined based on the ohmic voltage drop time.

5. The heating control method according to claim 4, characterized in that: The step of determining the target voltage threshold from the voltage limit data, and determining the pulse current based on the target voltage threshold, the ohmic internal resistance, and the battery voltage, comprises: determining the pulse charging voltage threshold in the voltage limit data as a first target voltage threshold; A charging pulse current is determined based on the first target voltage threshold, the ohmic internal resistance, and the battery voltage.

6. The heating control method according to claim 4, characterized in that: The step of determining the target voltage threshold from the voltage limit data, and determining the charging pulse current based on the target voltage threshold, the ohmic internal resistance, and the battery voltage, comprises: determining the pulse discharge voltage threshold in the voltage limit data as the second target voltage threshold; A discharge pulse current is determined based on the second target voltage threshold, the ohmic internal resistance, and the battery voltage.

7. The heating control method according to claim 1, characterized in that: After the charging pulse current and the discharging pulse current are controlled based on the pulse frequency to alternately electrically heat the battery, the method further includes: Acquiring a temperature change value of the battery based on a preset interval duration; If the temperature change value is equal to a preset temperature threshold, the electrical heating of the battery is stopped.

8. The heating control method according to claim 1, characterized in that: The method comprises: If it is detected that the battery temperature and / or the remaining power of the battery have changed, the steps of determining the pulse current and the pulse frequency for heating the battery, and controlling the charging pulse current and the discharging pulse current based on the pulse frequency to alternately electrically heat the battery are executed.

9. A vehicle, characterized in that: The vehicle comprises: A memory for storing executable program codes; A processor is used to call and run the executable program code from the memory so that the vehicle executes the heating control method as claimed in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer readable storage medium stores a computer program code, and when the computer program is run on a vehicle, the heating control method according to any one of claims 1 to 8 is executed.

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