Vehicle battery heating method and device, vehicle-mounted terminal and vehicle

Abstract

The invention provides a vehicle battery heating method and device, a vehicle-mounted terminal and a vehicle, and the method comprises the steps: monitoring the temperature of a battery and the charge quantity of the battery in real time, so as to preheat the vehicle battery through the heat consumed by the vehicle battery in a low-temperature and low-charge state of the battery; whether the battery is heated or not is determined according to the comparison result of the vehicle battery consumed heat and the battery unfreezing energy, and the situation that when the unfreezing energy is smaller than the battery heating consumed energy, a battery heating strategy is still called is avoided; the problem that the driving endurance and even lie down of a user who may deteriorate low-temperature low-charge-quantity driving is avoided, normal starting and running of the vehicle in a low-temperature environment are guaranteed, vehicle faults or performance reduction caused by battery problems are avoided, and therefore the driving experience of the user is improved; through accurate temperature control and heat management, the stability and performance of the vehicle in various environments are improved, and subjective judgment of designers on low charge quantity is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of battery thermal management, and in particular to a vehicle battery heating method, device, vehicle-mounted terminal and vehicle. Background Art

[0002] The power battery of electric vehicles is mainly lithium-ion batteries. The performance of lithium-ion batteries will change with the change of temperature, and the temperature of lithium-ion batteries is greatly affected by the ambient temperature. At the same time, the battery charging and discharging, battery heating or cooling modules will also affect the battery temperature.

[0003] Under low temperature conditions, most of the energy in the power battery is frozen in the battery cell and not released, causing the attenuation of the available capacity of the battery. Therefore, how to develop the frozen energy of the battery at low temperatures is crucial to the performance of the battery. Especially at low SOC (State of Charge), tapping the frozen energy inside the power battery is of great significance to increasing the battery life of electric vehicles. At present, the usual practice is to actively heat the low-temperature battery. Since the energy for battery heating comes from the power battery, if the low-temperature and low-SOC battery is heated, the battery life of the electric vehicle will be even worse. In severe cases, it may cause the electric vehicle to break down, which will inevitably cause user complaints and affect the user experience. Summary of the invention

[0004] The present application provides a vehicle battery heating method, device, vehicle-mounted terminal and vehicle to solve the above-mentioned technical problems.

[0005] A vehicle battery heating method provided in an embodiment of the present application includes: detecting a current vehicle battery cell temperature and a vehicle battery charge, and obtaining a vehicle battery consumption heat amount when the current vehicle battery cell temperature is less than a preset temperature threshold and the vehicle battery charge amount is less than or equal to a preset battery charge amount; preheating the vehicle battery by using the vehicle battery consumption heat amount to obtain a preheated vehicle battery cell temperature, and calculating a battery thawing energy according to the vehicle battery charge amount, the current vehicle battery cell temperature and the preheated vehicle battery cell temperature; if the vehicle battery consumption heat amount is greater than or equal to the battery thawing energy, heating of the vehicle battery is prohibited, and if the vehicle battery consumption heat amount is less than the battery thawing energy, heating of the vehicle battery is controlled; the battery thawing energy represents the heat energy required to restore the battery cell to normal function in a low temperature environment.

[0006] In one embodiment of the present application, the heat consumed by a vehicle battery is obtained, including: obtaining heater heat, battery cell internal resistance heat, and exchange heat; the exchange heat represents the heat transferred from the vehicle battery to the environment; and the heat consumed by the vehicle battery is obtained based on the heater heat, battery cell internal resistance heat, and exchange heat.

[0007] In one embodiment of the present application, obtaining heater heat includes: collecting sample vehicle battery coolant temperatures, calibrating the heater power for each of the sample vehicle battery coolant temperatures according to a preset functional change relationship, and obtaining a functional relationship between temperature and heater heat; detecting a current coolant temperature of the vehicle battery, and obtaining the heater heat based on the current coolant temperature of the vehicle battery and the functional relationship between temperature and heater heat.

[0008] In one embodiment of the present application, obtaining the internal resistance heat of the battery cell includes: performing a search operation in a battery internal resistance data table that is calibrated in advance or in real time according to the current vehicle battery cell temperature to obtain the battery internal resistance; detecting the driving discharge current of the vehicle battery, and obtaining the internal resistance heat of the battery cell according to the driving discharge current and the battery internal resistance.

[0009] In one embodiment of the present application, obtaining exchange heat includes: performing a search operation in a temperature drop rate data table that is calibrated in advance or in real time according to the current vehicle battery cell temperature to obtain the temperature drop rate; obtaining the exchange heat according to the temperature drop rate, the specific heat capacity of the vehicle battery, the mass of the vehicle battery cell, and the number of single cells of the vehicle battery.

[0010] In one embodiment of the present application, the battery thawing energy is calculated based on the vehicle battery charge, the current vehicle battery cell temperature and the vehicle battery cell temperature after preheating, including: performing a search operation in a preset battery cell discharge power data table based on the current vehicle battery cell temperature and the current vehicle battery charge to obtain the vehicle battery cell discharge power before preheating, and performing a search operation in the battery cell discharge power data table based on the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating to obtain the vehicle battery cell discharge power after preheating; determining the battery thawing energy based on the difference between the vehicle battery cell discharge power after preheating and the vehicle battery cell discharge power before preheating.

[0011] In one embodiment of the present application, the battery thawing energy is calculated based on the vehicle battery charge, the current vehicle battery cell temperature and the vehicle battery cell temperature after preheating, and also includes: if the vehicle battery cell discharge power before preheating is not found in the preset battery cell discharge power data table based on the current vehicle battery cell temperature and the current vehicle battery charge, then the current vehicle battery cell temperature and the current vehicle battery charge are recorded as current data points; if the vehicle battery cell discharge power after preheating is not found in the battery cell discharge power data table based on the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating; then the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating are recorded as post-preheating data points; linear interpolation calculation is performed based on the current data points and the post-preheating data points to obtain the battery thawing energy.

[0012] The vehicle battery heating device provided in the embodiment of the present application includes: a detection module, which is used to detect the current vehicle battery cell temperature and the vehicle battery charge, and obtain the vehicle battery consumption heat when the current vehicle battery cell temperature is less than a preset temperature threshold and the vehicle battery charge is less than or equal to the preset battery charge; a preheating module, which is used to preheat the vehicle battery through the vehicle battery consumption heat to obtain the vehicle battery cell temperature after preheating, and calculate the battery thawing energy according to the vehicle battery charge, the current vehicle battery cell temperature and the vehicle battery cell temperature after preheating; a heating module, which is used to prohibit heating the vehicle battery if the vehicle battery consumption heat is greater than or equal to the battery thawing energy, and to control the heating of the vehicle battery if the vehicle battery consumption heat is less than the battery thawing energy; the battery thawing energy represents the heat energy required to restore the battery cell to normal function in a low temperature environment.

[0013] An embodiment of the present application provides a vehicle-mounted terminal, including a processor, a memory and a communication bus; the communication bus is used to connect the processor and the memory; the processor is used to execute a computer program stored in the memory to implement the above-mentioned vehicle battery heating method.

[0014] The beneficial effects of the present application are as follows: by real-time monitoring of the battery cell temperature and the battery charge, the vehicle battery is preheated by the heat consumed by the vehicle battery when the battery is at a low temperature and at a low charge, and a decision is made whether to heat the battery based on a comparison of the heat consumed by the vehicle battery and the battery thawing energy, thereby avoiding calling the battery heating strategy when the "thawing" energy is less than the energy consumed for battery heating; avoiding the problem of users driving at low temperatures and at a low charge, which may worsen the driving range or even cause the vehicle to break down, ensuring the normal starting and operation of the vehicle in a low temperature environment, avoiding vehicle failure or performance degradation caused by battery problems, and thus improving the user's driving experience; through precise temperature control and heat management, the stability and performance of the vehicle in various environments are improved, avoiding the subjective judgment of designers on the low charge.

[0015] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0017] Figure 1 is a flow chart of a vehicle battery heating method shown in an exemplary embodiment of the present application;

[0018] Figure 2 is a schematic diagram of a method for heating a battery during low-temperature and low-SOC driving, shown in an exemplary embodiment of the present application;

[0019] Figure 3 is a block diagram of a vehicle battery heating device shown in an exemplary embodiment of the present application;

[0020] Figure 4 It is a structural schematic diagram of a vehicle-mounted terminal shown in an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0021] The following will describe the implementation methods of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for illustrating the present application, not for limiting the scope of protection of the present application.

[0022] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application, and thus the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0023] In the following description, a large number of details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present application difficult to understand.

[0024] The embodiments of the present application respectively provide a vehicle battery heating method, a vehicle battery heating device, a vehicle-mounted terminal, and a vehicle, which will be described in detail below.

[0025] First of all, it should be noted that the main problem faced by the battery when the vehicle battery is in a low-temperature and low-charge state is that the energy of the battery is used for heating the low-charge state. At this time, since the charge of the vehicle battery is too low, the heating of the PTC (Positive Temperature Coefficient, vehicle heater) may cause the battery power to drop, causing the vehicle to break down during low-temperature driving. This application uses the difference between the energy after the battery cell is heated and the PTC energy to judge, that is, if the energy obtained by the battery heating is greater than the energy consumed by the PTC heating, the heating is started, otherwise the heating is stopped. By real-time monitoring of the battery cell temperature and the battery charge, the vehicle battery is preheated by the heat consumed by the vehicle battery when the battery is in a low-temperature and low-charge state, and the battery is heated based on the comparison result of the heat consumed by the vehicle battery and the battery thawing energy, so as to avoid calling the battery heating strategy when the "thawing" energy is less than the battery heating energy consumption; it avoids the problem of worsening the driving range or even breaking down of users who drive at low temperatures and low charges, and ensures the normal start and operation of the vehicle in a low-temperature environment.

[0026] See also Figure 1 , Figure 1 FIG. 1 shows a flow chart of a vehicle battery heating method according to an embodiment of the present application. Figure 1 As shown, the method at least includes steps S110 to S130, which are described in detail as follows:

[0027] Step S110, detecting the current vehicle battery cell temperature and the vehicle battery charge, and obtaining the vehicle battery consumption heat when the current vehicle battery cell temperature is less than a preset temperature threshold and the vehicle battery charge is less than or equal to a preset battery charge.

[0028] In one embodiment of the present application, the preset temperature threshold is -25°C, and the preset battery charge is 5% SOC. If it is detected that the current vehicle battery cell temperature is -28°C and the vehicle battery charge is 5% SOC, the heat consumed by the vehicle battery is obtained.

[0029] Step S120, preheating the vehicle battery by consuming heat of the vehicle battery to obtain the vehicle battery cell temperature after preheating, and calculating the battery thawing energy according to the vehicle battery charge, the current vehicle battery cell temperature and the vehicle battery cell temperature after preheating.

[0030] Step S130, if the heat consumed by the vehicle battery is greater than or equal to the battery thawing energy, heating of the vehicle battery is prohibited; if the heat consumed by the vehicle battery is less than the battery thawing energy, heating of the vehicle battery is controlled; the battery thawing energy represents the heat energy required to restore the normal function of the battery cell in a low temperature environment.

[0031] exist Figure 1 In the technical solution shown, by real-time monitoring of the battery cell temperature and the battery charge, the vehicle battery is preheated by the heat consumed by the vehicle battery when the battery is at a low temperature and low charge, and a decision is made whether to heat the battery based on a comparison result of the heat consumed by the vehicle battery and the battery thawing energy, thereby avoiding calling the battery heating strategy when the "thawing" energy is less than the battery heating energy consumption; avoiding the problem of users' driving range or even breakdown when driving at low temperatures and low charge, ensuring the normal starting and operation of the vehicle in a low temperature environment, avoiding vehicle failure or performance degradation due to battery problems, and thus improving the user's driving experience; through precise temperature control and heat management, the stability and performance of the vehicle in various environments are improved, avoiding the subjective judgment of designers on low charge.

[0032] In one embodiment of the present application, obtaining the heat consumed by a vehicle battery includes: obtaining heater heat, cell internal resistance heat, and exchange heat; the exchange heat represents the heat transferred from the vehicle battery to the environment; and obtaining the heat consumed by the vehicle battery based on the heater heat, cell internal resistance heat, and exchange heat.

[0033] As an example, the heat consumed by the vehicle battery is Econsume, the heat of the heater is Eptc(Tw), the heat of the battery cell internal resistance is Er(r), and the heat of the exchange is Ee(v). The heat consumed by the vehicle battery is obtained based on the heat of the heater, the heat of the battery cell internal resistance, and the heat of the exchange.

[0034] Econsume=Eptc(Tw)+Er(r)-Ee(v),

[0035] Eptc(Tw) is the heater heat, Er(r) is the cell internal resistance heat, Ee(v) is the exchange heat,

[0036] Where Eptc(Tw)=E(Tw)*T;

[0037] Eptc(Tw) is the heater heat, E(Tw) is the heater power, and T is the preheating time;

[0038] Er(r)=E(r)*T,

[0039] Er(r) is the internal resistance heat of the battery cell, E(r) is the internal resistance heat power of the battery cell, and T is the preheating time.

[0040] In one embodiment of the present application, obtaining heater heat includes: collecting sample vehicle battery coolant temperatures, calibrating the heater power for each sample vehicle battery coolant temperature according to a preset functional change relationship, and obtaining a functional relationship between temperature and heater heat; detecting the current coolant temperature of the vehicle battery, and obtaining the heater heat according to the current coolant temperature of the vehicle battery and the functional relationship between temperature and heater heat.

[0041] As an example, the preset function variation relationship characterizes that the heating power of the heater PTC is a function of the battery coolant temperature Tw. The lower the temperature, the higher the heating power. According to the preset function variation relationship, the heater power is calibrated for each sample vehicle battery coolant temperature, which can be obtained through calibration or from the specification sheet of the PTC manufacturer; an expression for calculating or finding the heating power corresponding to the water temperature is obtained:

[0042] E(Tw)=α*Tw,

[0043] Wherein, E(Tw) is the heater power, α is the coefficient, and Tw is the battery coolant temperature. As a specific example, Table 1 is a corresponding data table of the battery coolant temperature and the heater power shown in the embodiment of the present application, as shown in Table 1, including the water temperature Tw and the power E(Tw).

[0044] Table 1

[0045] T -40 -35 -25 -15 -10 0 10 E(Tw) P1 P2 P3 P4 P5 P6 P7

[0046] In one embodiment of the present application, obtaining the internal resistance heat of the battery cell includes: performing a search operation in a preset battery internal resistance data table according to the current vehicle battery cell temperature to obtain the battery internal resistance; detecting the driving discharge current of the vehicle battery, and obtaining the internal resistance heat of the battery cell according to the driving discharge current and the battery internal resistance.

[0047] As an example, the vehicle battery's driving discharge current is I, and the internal resistance heat of the battery cell is calculated as:

[0048] E(r)=I 2 *r,

[0049] Wherein, E(r) is the cell internal resistance power, I is the driving discharge current of the vehicle battery, r is the battery internal resistance, as an example, the battery internal resistance is the DC internal resistance DCR (Direct Current Resistance) of a single cell of the battery pack, Table 2 is a battery internal resistance data table, including temperature, battery charge and battery internal resistance, the temperature represents the current vehicle battery cell temperature, i, j, m, n are natural numbers, specifically, Table 3 is a battery internal resistance data example Table 1, Table 4 is a battery internal resistance data example Table 2 and Table 5 is a battery internal resistance data example Table 3, as shown in Table 3, Table 3 represents the battery internal resistance value corresponding to the temperature between -20℃ and 55℃ and the charge between 3% and 30% SOC, Table 4 represents the battery internal resistance value corresponding to the temperature between -20℃ and 55℃ and the charge between 35% and 65% SOC. Resistance value, Table 5 represents the battery internal resistance value corresponding to the temperature between -20℃ and 55℃ and the charge between 70% and 95% SOC. Table 6 is the battery cell DCR-MAP table, which represents the DC internal resistance DCR value. Specifically, the battery internal resistance query tag is determined by the current vehicle battery cell temperature and the current battery charge. For example, when the current vehicle battery cell temperature is -20℃ and the battery charge is 5% SOC, the corresponding battery internal resistance query tag is R(1, 2). Through R(1, 2), the battery single cell internal resistance is found to be 13.8mΩ in the battery cell DCR-MAP table generated in advance or in real time.

[0050] Table 2

[0051]

[0052] Table 3

[0053]

[0054]

[0055] Table 4

[0056]

[0057]

[0058] Table 5

[0059]

[0060] Table 6

[0061]

[0062] In one embodiment of the present application, obtaining exchange heat includes: performing a search operation in a temperature drop rate data table that is calibrated in advance or in real time according to the current vehicle battery cell temperature to obtain the temperature drop rate; obtaining the exchange heat according to the temperature drop rate, the specific heat capacity of the vehicle battery, the mass of the vehicle battery cell, and the number of single cells of the vehicle battery.

[0063] As an example, Table 7 is a temperature drop rate data table, as shown in Table 7, including vehicle battery cell temperature, battery charge and temperature drop rate, i, j, m, n are natural numbers; according to the current vehicle battery cell temperature, a search operation is performed in the pre- or real-time calibrated temperature drop rate data table to obtain the temperature drop rate, and the exchange heat is obtained by the following formula:

[0064] Ee(t, SOC)=V*c*m*n,

[0065] Among them, Ee(t, SOC) is the exchange heat, V is the temperature drop rate of the battery pack, c is the specific heat capacity of the battery, m is the mass of a single cell, n is the number of single cells in the battery pack, and t is the current vehicle battery cell temperature.

[0066] As an example, Table 7 is a temperature drop rate data table, including temperature, battery charge and temperature drop rate, the temperature represents the current vehicle battery cell temperature, i, j, m, n are natural numbers, specifically, Table 8 is a temperature drop rate data example table 1, Table 9 is a temperature drop rate data example table 2 and Table 10 is a temperature drop rate data example table 3, as shown in Table 8, Table 8 represents the temperature drop rate query value corresponding to when the temperature is -20℃~55℃ and the charge is between 3%~30% SOC, Table 9 represents when the temperature is Table 10 represents the temperature drop rate query values ​​corresponding to -20℃~55℃, and charge 35%~65% SOC. Table 10 represents the temperature drop rate query values ​​corresponding to -20℃~55℃, and charge 70%~95% SOC. Specifically, the battery internal resistance query tag is determined by the current vehicle battery cell temperature and the current battery charge. For example, when the current vehicle battery cell temperature is -20℃ and the battery charge is 5% SOC, the corresponding temperature drop rate query value is V(1, 2).

[0067] Table 7

[0068]

[0069] Table 8

[0070]

[0071]

[0072] Table 9

[0073]

[0074] Table 10

[0075]

[0076]

[0077] In one embodiment of the present application, the battery thawing energy is calculated based on the heat consumed by the vehicle battery, including: performing a search operation in a preset battery cell discharge power data table according to the current vehicle battery cell temperature and the current vehicle battery charge to obtain the vehicle battery cell discharge power before preheating, and performing a search operation in the battery cell discharge power data table according to the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating to obtain the vehicle battery cell discharge power after preheating; the battery thawing energy is determined according to the difference between the vehicle battery cell discharge power after preheating and the vehicle battery cell discharge power before preheating.

[0078] As an example, Table 11 is an example table 1 of battery cell discharge power, including temperature, battery charge and battery cell discharge power, the temperature represents the temperature of the vehicle battery cell, Table 12 is an example table 2 of battery cell discharge power and Table 13 is an example table 3 of battery cell discharge power; as shown in Table 11, Table 11 represents the battery cell discharge power query values ​​corresponding to the SOC between 3% and 30% when the temperature is -30℃ to 20℃ and the charge is between 35% and 65%, and Table 13 represents the battery cell discharge power query values ​​corresponding to the SOC between 70% and 95% when the temperature is -30℃ to 20℃. Specifically, a search operation is performed in a preset battery cell discharge power data table according to the current vehicle battery cell temperature and the current vehicle battery charge to obtain the vehicle battery cell discharge power before preheating, and a search operation is performed in a battery cell discharge power data table according to the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating to obtain the vehicle battery cell discharge power after preheating. The battery cell discharge power is determined by two factors: temperature and SOC. The battery thawing energy Eb(t, SOC) is determined according to the difference between the vehicle battery cell discharge power after preheating and the vehicle battery cell discharge power before preheating. Generally, at the same temperature, the higher the SOC, the higher the energy, that is, the higher the discharge energy; at the same SOC, the higher the temperature, the higher the energy, that is, the higher the discharge energy.

[0079] Table 11

[0080]

[0081]

[0082] Table 12

[0083]

[0084] Table 13

[0085]

[0086] As an example, Figure 2 A schematic diagram of a method for heating a battery during low-temperature and low-SOC driving is shown in an embodiment of the present application. When it is detected that the current vehicle driving environment is low-temperature and low-SOC driving, the heat consumed by the vehicle battery Econsume is calculated by the BMS (Battery Management System), Econsume=Eptc(Tw)+Er(r)-Ee(v), where Eptc(Tw) is the heater heat, Er(r) is the cell internal resistance heat, and Ee(v) is the exchange heat. The battery thawing energy is calculated by the battery thawing module as Eb(t, SOC). If Eb(t, SOC)-Econsume>0, heating is performed during low-SOC driving. If Eb(t, SOC)-Econsume≤0, PTC heating is prohibited and the vehicle limps.

[0087] As an example, the preset temperature threshold is -25°C, and the preset battery charge is 5% SOC. When the ambient temperature is detected to be -30°C, the current vehicle battery cell temperature is detected to be -28°C, and the current vehicle battery charge is detected to be 5% SOC. Since the current vehicle battery cell temperature is less than -25°C and the current vehicle battery charge is equal to 5% SOC, the heating battery consumption energy module is triggered to obtain the vehicle battery consumption heat Econsume, that is, the heater heat Eptc (Tw), the cell internal resistance heat Er (r) and the exchange heat Ee (v). The vehicle battery consumption heat Econsum calculated by the three can raise the battery temperature to -26°C, that is, the vehicle battery cell temperature after preheating is -26°C. According to the current vehicle battery cell temperature of -28°C and the current vehicle battery charge of 5% SOC, a search operation is performed in Table 9 to obtain the vehicle battery cell discharge power before preheating is P(2, 2). According to the vehicle battery cell temperature after preheating of -26°C and the current vehicle battery charge of 5% SOC, a search operation is performed in the battery cell discharge power data table to obtain the vehicle battery cell discharge power after preheating P(3, 2). As the battery cell is heated, the amount of electricity that can be released, that is, the SOC, also increases. For example, to 10% SOC, that is, after preheating, The vehicle battery charge is 10% SOC. According to the vehicle battery cell temperature after preheating -26°C and the vehicle battery charge 10% SOC after preheating, a search operation is performed in the battery cell discharge power data table, and the vehicle battery cell discharge power after preheating is obtained to be P(3, 3). The battery thawing energy is Eb(t, SOC)=P(3, 3)-P(2, 2). If Eb(t, SOC)=P(3, 3)-P(2, 2)>Econsum, battery heating is allowed, otherwise, battery heating is prohibited.

[0088] In one embodiment of the present application, if the temperature and SOC parameters of the battery thawing energy Eb(t, SOC) do not necessarily completely correspond to the above MAP table, the battery thawing energy can be obtained by linear interpolation. In the above embodiment, the battery thawing energy is calculated based on the heat consumed by the vehicle battery, and further includes: if the pre-preheating vehicle battery cell discharge power is not found in the preset cell discharge power data table according to the current vehicle battery cell temperature and the current vehicle battery charge, the current vehicle battery cell temperature and the current vehicle battery charge are recorded as the current data point; if the pre-preheating vehicle battery cell discharge power is not found in the cell discharge power data table according to the pre-preheating vehicle battery cell temperature and the pre-preheating vehicle battery charge; the pre-preheating vehicle battery cell temperature and the pre-preheating vehicle battery charge are recorded as the pre-preheating data point; and a linear interpolation calculation is performed based on the current data point and the pre-preheating data point to obtain the heating battery thawing energy.

[0089] In one embodiment of the present application, a linear interpolation calculation is performed based on the current data point and the data point after preheating to obtain the heating battery thawing energy, including performing a linear interpolation calculation on the current data point to obtain the vehicle battery cell discharge power before preheating, performing a linear interpolation calculation on the data point after preheating to obtain the vehicle battery cell discharge power after preheating, and determining the battery thawing energy based on the difference between the vehicle battery cell discharge power after preheating and the vehicle battery cell discharge power before preheating.

[0090] Figure 3 A block diagram of a vehicle battery heating device according to an exemplary embodiment of the present application is shown. Figure 3 As shown, a vehicle battery heating device 300 according to an embodiment of the present application includes: a detection module 310, a preheating module 320 and a heating module 330, the detection module is used to detect the current vehicle battery cell temperature and the vehicle battery charge, and obtain the vehicle battery consumption heat when the current vehicle battery cell temperature is less than a preset temperature threshold and the vehicle battery charge is less than or equal to the preset battery charge; the preheating module is used to preheat the vehicle battery through the vehicle battery consumption heat to obtain the preheated vehicle battery cell temperature, and calculate the battery thawing energy according to the current vehicle battery cell temperature and the preheated vehicle battery cell temperature; the heating module is used to prohibit heating the vehicle battery if the vehicle battery consumption heat is greater than or equal to the battery thawing energy, and to control the vehicle battery to heat if the vehicle battery consumption heat is less than the battery thawing energy; the battery thawing energy represents the heat energy required to restore the battery cell to normal function in a low temperature environment. By real-time monitoring of the battery cell temperature and the battery charge, the vehicle battery is preheated by the heat consumed by the vehicle battery when the battery is at a low temperature and at a low charge, and a decision is made whether to heat the battery based on a comparison of the heat consumed by the vehicle battery and the battery thawing energy, thereby avoiding calling the battery heating strategy when the "thawing" energy is less than the energy consumed for battery heating. This avoids the problem of users driving at low temperatures and at a low charge, which may worsen the driving range or even cause the vehicle to break down, ensures the normal starting and operation of the vehicle in a low temperature environment, avoids vehicle failure or performance degradation caused by battery problems, and thus improves the user's driving experience. Through precise temperature control and heat management, the stability and performance of the vehicle in various environments are improved, avoiding the subjective judgment of designers on low charge.

[0091] In one embodiment of the present application, the vehicle heating device also includes an acquisition module for acquiring heater heat, battery cell internal resistance heat and exchange heat; the exchange heat represents the heat transferred from the vehicle battery to the environment; the vehicle battery consumption heat is obtained based on the heater heat, battery cell internal resistance heat and exchange heat.

[0092] As an example, the heat consumed by the vehicle battery is Econsume, the heat of the heater is Eptc(Tw), the heat of the battery cell internal resistance is Er(r), and the heat of the exchange is Ee(v). The heat consumed by the vehicle battery is obtained based on the heat of the heater, the heat of the battery cell internal resistance, and the heat of the exchange.

[0093] Econsume=Eptc(Tw)+Er(r)-Ee(v),

[0094] Eptc(Tw) is the heater heat, Er(r) is the cell internal resistance heat, Ee(v) is the exchange heat,

[0095] Where Eptc(Tw)=E(Tw)*T;

[0096] Eptc(Tw) is the heater heat, E(Tw) is the heater power, and T is the preheating time;

[0097] Er(r)=E(r)*T,

[0098] Er(r) is the internal resistance heat of the battery cell, E(r) is the internal resistance power of the battery cell, and T is the preheating time.

[0099] In one embodiment of the present application, an acquisition module is used to collect the sample vehicle battery coolant temperature, calibrate the heater power for each sample vehicle battery coolant temperature according to a preset functional change relationship, and obtain the functional relationship between temperature and heater heat; detect the current coolant temperature of the vehicle battery, and obtain the heater heat according to the current coolant temperature of the vehicle battery and the functional relationship between temperature and heater heat.

[0100] As an example, the preset function variation relationship characterizes that the heating power of the heater PTC is a function of the battery coolant temperature Tw. The lower the temperature, the higher the heating power. According to the preset function variation relationship, the heater power is calibrated for each sample vehicle battery coolant temperature, which can be obtained through calibration or from the specification sheet of the PTC manufacturer; an expression for calculating or finding the heating power corresponding to the water temperature is obtained:

[0101] E(Tw)=α*Tw,

[0102] Where E(Tw) is the heater power, α is the coefficient, and Tw is the battery coolant temperature.

[0103] In one embodiment of the present application, the acquisition module is used to perform a search operation in a battery internal resistance data table that has been calibrated in advance or in real time according to the current vehicle battery cell temperature to obtain the battery internal resistance; detect the driving discharge current of the vehicle battery, and obtain the cell internal resistance heat based on the driving discharge current and the battery internal resistance.

[0104] As an example, the vehicle battery's driving discharge current is I, and the internal resistance heat of the battery cell is calculated as:

[0105] E(r)=I 2 *r,

[0106] Among them, E(r) is the internal resistance power of the battery cell, I is the driving discharge current of the vehicle battery, and r is the internal resistance of the battery.

[0107] In one embodiment of the present application, the acquisition module is used to perform a search operation in a temperature drop rate data table that has been calibrated in advance or in real time according to the current vehicle battery cell temperature to obtain the temperature drop rate; and obtain the exchange heat according to the temperature drop rate, the specific heat capacity of the vehicle battery, the mass of the vehicle battery cell, and the number of single cells of the vehicle battery.

[0108] As an example, the exchange heat is obtained through the following formula: Ee(t, SOC) = V*c*m*n, where Ee(t, SOC) is the exchange heat, V is the temperature drop rate of the battery pack, c is the specific heat capacity of the battery, m is the mass of a single cell, n is the number of single cells in the battery pack, and t is the current vehicle battery cell temperature.

[0109] In one embodiment of the present application, the preheating module is used to perform a search operation in a preset battery cell discharge power data table according to the current vehicle battery cell temperature and the current vehicle battery charge to obtain the vehicle battery cell discharge power before preheating, and to perform a search operation in the battery cell discharge power data table according to the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating to obtain the vehicle battery cell discharge power after preheating; the battery thawing energy is determined according to the difference between the vehicle battery cell discharge power after preheating and the vehicle battery cell discharge power before preheating.

[0110] As an example, the preset temperature threshold is -25°C, and the preset battery charge is 5% SOC. When the ambient temperature is detected to be -30°C, the current vehicle battery cell temperature is detected to be -28°C, and the current vehicle battery charge is detected to be 5% SOC. Since the current vehicle battery cell temperature is less than -25°C and the current vehicle battery charge is equal to 5% SOC, the heating battery consumption energy module is triggered to obtain the vehicle battery consumption heat Econsume, that is, the heater heat Eptc (Tw), the cell internal resistance heat Er (r) and the exchange heat Ee (v). The vehicle battery consumption heat Econsum calculated by the three can raise the battery temperature to -26°C, that is, the vehicle battery cell temperature after preheating is -26°C. According to the current vehicle battery cell temperature of -28°C and the current vehicle battery charge of 5% SOC, a search operation is performed in Table 9 to obtain the vehicle battery cell discharge power before preheating is P(2, 2). According to the vehicle battery cell temperature after preheating of -26°C and the current vehicle battery charge of 5% SOC, a search operation is performed in the battery cell discharge power data table to obtain the vehicle battery cell discharge power after preheating P(3, 2). As the battery cell is heated, the amount of electricity that can be released, that is, the SOC, also increases. For example, to 10% SOC, that is, after preheating, The vehicle battery charge is 10% SOC. According to the vehicle battery cell temperature after preheating -26°C and the vehicle battery charge 10% SOC after preheating, a search operation is performed in the battery cell discharge power data table, and the vehicle battery cell discharge power after preheating is obtained to be P(3, 3). The battery thawing energy is Eb(t, SOC)=P(3, 3)-P(2, 2). If Eb(t, SOC)=P(3, 3)-P(2, 2)>Econsum, battery heating is allowed, otherwise, battery heating is prohibited.

[0111] In one embodiment of the present application, the preheating module is used to record the current vehicle battery cell temperature and the current vehicle battery charge as current data points if the vehicle battery cell discharge power before preheating is not found in the preset battery cell discharge power data table according to the current vehicle battery cell temperature and the current vehicle battery charge; if the vehicle battery cell discharge power after preheating is not found in the battery cell discharge power data table according to the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating; the vehicle battery cell temperature after preheating and the vehicle battery charge after preheating are recorded as post-preheating data points; and linear interpolation calculation is performed based on the current data points and the post-preheating data points to obtain the battery thawing energy.

[0112] It should be noted that the device provided in the above embodiment and the method provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment, and will not be repeated here. In practical applications, the device provided in the above embodiment can distribute the above functions to different functional modules as needed, that is, divide the internal structure of the device into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0113] See also Figure 4 , Figure 4 is a structural diagram of a vehicle-mounted terminal shown in an exemplary embodiment of the present application. It should be noted that: Figure 4 The vehicle-mounted terminal 400 shown is only an example and should not bring any limitation to the functions and usage area of ​​the embodiments of the present application.

[0114] like Figure 4 As shown, the vehicle terminal 400 includes a processor 401, a memory 402 and a communication bus 403; the communication bus 403 is used to connect the processor 401 and the memory 402; the processor 401 is used to execute the computer program stored in the memory 402 to implement one or more methods as in the above embodiments.

[0115] The vehicle-mounted terminal provided in the present application includes a processor, a memory, a transceiver and a communication interface. The memory and the communication interface are connected to the processor and the transceiver and complete communication with each other. The memory is used to store computer programs, the communication interface is used to communicate, and the processor and the transceiver are used to run computer programs so that the electronic device executes the various steps of the above method.

[0116] In this embodiment, the memory may include a random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0117] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0118] The above embodiments are merely illustrative of the principles and effects of the present application, and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A vehicle battery heating method, characterized in that: The method comprises: Detecting the current vehicle battery cell temperature and the vehicle battery charge, and obtaining the vehicle battery consumption heat when the current vehicle battery cell temperature is less than a preset temperature threshold and the vehicle battery charge is less than or equal to a preset battery charge; Preheating the vehicle battery by consuming heat from the vehicle battery to obtain a preheated vehicle battery cell temperature, and calculating battery thawing energy based on the vehicle battery charge, the current vehicle battery cell temperature, and the preheated vehicle battery cell temperature; If the heat consumed by the vehicle battery is greater than or equal to the battery thawing energy, heating of the vehicle battery is prohibited; if the heat consumed by the vehicle battery is less than the battery thawing energy, heating control is performed on the vehicle battery.

2. The vehicle battery heating method according to claim 1, characterized in that: Obtain the heat consumed by the vehicle battery, including: Acquire heater heat, cell internal resistance heat, and exchange heat; the exchange heat represents the heat transferred from the vehicle battery to the environment; The heat consumed by the vehicle battery is obtained according to the heater heat, the cell internal resistance heat and the exchange heat.

3. The vehicle battery heating method according to claim 2, characterized in that: Get heater heat, including: Collecting the battery coolant temperature of the sample vehicles, calibrating the heater power for each of the battery coolant temperatures of the sample vehicles, and obtaining a functional relationship between the temperature and the heater heat; The current coolant temperature of the vehicle battery is detected, and the heater heat is obtained according to the current coolant temperature of the vehicle battery and a functional relationship between the temperature and the heater heat.

4. The vehicle battery heating method according to claim 2, characterized in that: Obtain the internal resistance heat of the battery cell, including: Performing a search operation in a battery internal resistance data table calibrated in advance or in real time according to the current vehicle battery cell temperature to obtain the battery internal resistance; The driving discharge current of the vehicle battery is detected, and the internal resistance heat of the battery cell is obtained according to the driving discharge current and the internal resistance of the battery.

5. The vehicle battery heating method according to claim 2, characterized in that: Get the exchange heat, including: Performing a search operation in a temperature drop rate data table calibrated in advance or in real time according to the current vehicle battery cell temperature to obtain a temperature drop rate; The exchange heat is obtained according to the temperature drop rate, the specific heat capacity of the vehicle battery, the mass of a single cell of the vehicle battery, and the number of single cells of the vehicle battery.

6. The vehicle battery heating method according to claim 1, characterized in that: Calculating the battery thawing energy according to the vehicle battery charge, the current vehicle battery cell temperature and the preheated vehicle battery cell temperature includes: According to the current vehicle battery cell temperature and the current vehicle battery charge, a search operation is performed in a preset battery cell discharge power data table to obtain the vehicle battery cell discharge power before preheating, and according to the preheated vehicle battery cell temperature and the preheated vehicle battery charge, a search operation is performed in the battery cell discharge power data table to obtain the vehicle battery cell discharge power after preheating; The battery thawing energy is determined according to a difference between the discharge power of the vehicle battery cell after preheating and the discharge power of the vehicle battery cell before preheating.

7. The vehicle battery heating method according to claim 1, characterized in that: Calculating the battery thawing energy according to the vehicle battery charge, the current vehicle battery cell temperature and the preheated vehicle battery cell temperature also includes: If the vehicle battery cell discharge power before preheating is not found in the preset cell discharge power data table according to the current vehicle battery cell temperature and the current vehicle battery charge, the current vehicle battery cell temperature and the current vehicle battery charge are recorded as the current data point; If the preheated vehicle battery cell temperature and the preheated vehicle battery charge are not found in the cell discharge power data table, the preheated vehicle battery cell temperature and the preheated vehicle battery charge are recorded as the preheated data point; A linear interpolation calculation is performed based on the current data point and the preheated data point to obtain the battery thawing energy.

8. A vehicle battery heating device, characterized in that: The device comprises: A detection module, used to detect the current vehicle battery cell temperature and the vehicle battery charge, and obtain the vehicle battery consumption heat when the current vehicle battery cell temperature is less than a preset temperature threshold and the vehicle battery charge is less than or equal to a preset battery charge; A preheating module, used to preheat the vehicle battery by consuming heat from the vehicle battery, obtain a cell temperature of the vehicle battery after preheating, and calculate battery thawing energy according to the charge of the vehicle battery, the current cell temperature of the vehicle battery, and the cell temperature of the vehicle battery after preheating; A heating module is used to prohibit heating the vehicle battery if the heat consumed by the vehicle battery is greater than or equal to the battery thawing energy, and to control the heating of the vehicle battery if the heat consumed by the vehicle battery is less than the battery thawing energy; the battery thawing energy represents the heat energy required to restore the normal function of the battery cell in a low temperature environment.

9. A vehicle-mounted terminal, characterized in that: It comprises a processor, a memory and a communication bus; the communication bus is used to connect the processor and the memory; the processor is used to execute a computer program stored in the memory to implement the vehicle battery heating method as claimed in any one of claims 1 to 7.

10. A vehicle, characterized in that: It comprises the vehicle battery heating device as claimed in claim 8 or the vehicle-mounted terminal as claimed in claim 9.

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