Battery pack temperature correction method and device, controller and vehicle

Abstract

The invention discloses a battery pack temperature correction method and device, a controller and a vehicle, and the method comprises the steps: obtaining a battery pack temperature, a charging parameter, a heat dissipation parameter and a battery cell parameter of a battery pack in a super fast charging state; according to the battery pack temperature, the charging parameter, the heat dissipation parameter and the battery cell parameter of the battery pack, calculating a battery temperature difference generated by the connection resistance of the battery cells in the battery pack based on a preset energy formula about the connection resistance of each battery cell; according to the battery temperature difference, the battery pack temperature is corrected to obtain the target battery pack temperature, the original battery pack temperature is corrected through the calculated battery temperature difference, the obtained corrected target battery pack temperature is relatively reduced, and in the super fast charging state, the charging current searched based on the target battery pack may be increased; therefore, the charging speed of the battery pack is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and in particular to a battery pack temperature correction method, device, controller and vehicle. Background Art

[0002] There are more and more super-fast charging system battery packs on the market. When the battery pack is overcharged, it will generate heat, causing the battery temperature to rise. Since the battery charging capacity is related to the battery power (State of Charge, SOC) and temperature, when the battery pack temperature rises, the battery charging speed may slow down, resulting in longer charging time for users.

[0003] At present, the temperature of the battery pack is sampled by the top cover, that is, the temperature sensor is arranged on the upper surface of the battery pack aluminum shell. However, under this sampling method, the temperature sampling value of the battery pack is inaccurate and is higher than the actual battery pack temperature. The charging speed of the battery pack is related to the battery power and temperature. As the temperature rises, the charging rate decreases, which leads to a longer battery charging time. Summary of the invention

[0004] In view of the above problems, the present invention provides a battery pack temperature correction method, device, controller and vehicle to improve the charging speed of the battery pack under super fast charging state.

[0005] According to a first aspect of the present invention, a battery pack temperature correction method is provided, comprising:

[0006] In the super-fast charging state, obtain the battery pack temperature, charging parameters, heat dissipation parameters, and battery pack cell parameters;

[0007] According to the battery pack temperature, the charging parameters, the heat dissipation parameters and the battery cell parameters of the battery pack, based on a preset energy formula about the connection resistance of each battery cell, a battery temperature difference generated by the connection resistance of the battery cells in the battery pack is calculated, wherein the energy formula is used to characterize the calculation of the battery temperature difference through the heat generation and heat dissipation of the battery pack, the heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters, the battery cell parameters and the charging parameters, and the heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters and a preset heat exchange coefficient;

[0008] The battery pack temperature is corrected according to the battery temperature difference to obtain a target battery pack temperature.

[0009] Optionally, the charging parameters include charging current, charging resistance and charging time, the heat dissipation parameters include ambient temperature and coolant temperature in a thermal management system, and the battery cell parameters include battery cell weight and battery cell specific heat capacity;

[0010] The heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameter, the cell parameter of the battery pack and the charging parameter, including:

[0011] Calculating heat generated by the charging resistor according to the charging current, the charging resistor and the charging time;

[0012] Calculate the gain heat generation of the connection resistance according to the battery pack temperature, the charging current, the charging resistance, the charging time, the ambient temperature, the coolant temperature, the weight of the battery cells in the battery pack, and the specific heat capacity of the battery cells;

[0013] The heat generation of the battery pack is determined according to the heat generation of the charging resistor and the gain heat generation of the connection resistor.

[0014] Optionally, the heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameter and a preset heat exchange coefficient, including:

[0015] If the coolant in the thermal management system generates heat exchange with the battery pack, the heat dissipation of the battery pack is calculated according to the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature, the ambient temperature, the heat exchange coefficient between the battery pack and the coolant, the contact area between the battery pack and the coolant, and the coolant temperature;

[0016] If the coolant in the thermal management system does not generate heat exchange with the battery pack, the heat dissipation of the battery pack is calculated based on the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature and the ambient temperature.

[0017] Optionally, if the coolant in the thermal management system generates heat exchange with the battery pack, before the step of calculating the heat dissipation of the battery pack according to the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature, the ambient temperature, the heat exchange coefficient between the battery pack and the coolant, the contact area between the battery pack and the coolant, and the coolant temperature, the method further includes:

[0018] If the battery pack temperature is greater than a first temperature threshold, or the battery pack temperature is less than a second temperature threshold, the thermal management system is turned on to allow the coolant in the thermal management system to exchange heat with the battery pack; wherein the first temperature threshold is greater than the second temperature threshold.

[0019] Optionally, the calculating the battery temperature difference generated by the connection resistance of the battery cells in the battery pack based on a preset energy formula for the connection resistance of each battery cell includes:

[0020] Determining the amount of heat stored in the battery pack according to the difference between the heat generated by the battery pack and the heat dissipated by the battery pack;

[0021] The battery temperature difference is calculated according to the stored heat of the battery pack, the weight of the battery cell and the specific heat capacity of the battery cell.

[0022] Optionally, before the step in the super fast charging state, the method further includes:

[0023] If it is detected that the vehicle is connected to the charging pile, the maximum charging current and charging power of the charging pile are obtained;

[0024] If the maximum charging current of the charging pile reaches the fast charging current of the vehicle, and the charging power of the charging pile reaches the fast charging power of the vehicle, the vehicle is in a super fast charging state.

[0025] Optionally, the method further includes:

[0026] According to the target battery pack temperature, the charging current of the battery pack in the super fast charging state is adjusted.

[0027] According to a second aspect of the present invention, there is provided a battery pack temperature correction device, comprising:

[0028] The acquisition module is used to obtain the battery pack temperature, charging parameters, heat dissipation parameters, and battery cell parameters of the battery pack in the super fast charging state;

[0029] a calculation module, configured to calculate a battery temperature difference generated by the connection resistance of the battery cells in the battery pack according to the battery pack temperature, the charging parameters, the heat dissipation parameters and the battery cell parameters of the battery pack, based on a preset energy formula for the connection resistance of each battery cell, wherein the energy formula is used to characterize the calculation of the battery temperature difference through the heat generation and heat dissipation of the battery pack, the heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters, the battery cell parameters and the charging parameters, and the heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters and a preset heat exchange coefficient;

[0030] The correction module is used to correct the battery pack temperature according to the battery temperature difference to obtain a target battery pack temperature.

[0031] According to a third aspect of the present invention, a controller is provided, the controller comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the aforementioned battery pack temperature correction method.

[0032] According to a fourth aspect of the present invention, a vehicle is provided, the vehicle comprising a vehicle body and a controller installed in the vehicle body, wherein the controller executes the aforementioned battery pack temperature correction method.

[0033] The above one or more technical solutions in the embodiments of this specification have at least the following technical effects:

[0034] The embodiments of this specification provide a battery pack temperature correction method, device, controller and vehicle, which correct the original battery pack temperature by calculating the battery temperature difference, so that the corrected target battery pack temperature is relatively lower. In the super fast charging state, the charging current based on the target battery pack search may increase, thereby improving the charging speed of the battery pack.

[0035] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Also, throughout the accompanying drawings, the same reference figures are used to represent the same components. In the drawings:

[0037] Figure 1 A flow chart of a battery pack temperature correction method in an embodiment of the present invention is shown.

[0038] Figure 2 A block diagram of a battery pack temperature correction device in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0042] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] The embodiment of the present invention provides a battery pack temperature correction method, combined with Figure 1 As shown in the flowchart, the battery pack temperature correction method includes steps 101 to 103:

[0044] Step 101: Under super-fast charging state, obtain battery pack temperature, charging parameters, heat dissipation parameters, and battery cell parameters of the battery pack;

[0045] In this embodiment, super fast charging refers to using a higher power current to charge the battery pack from 20% to 80% or even higher in a short period of time.

[0046] At present, the battery pack adopts top cover sampling, that is, the temperature sensor is arranged on the upper surface of the aluminum shell of the battery pack. The cells in the battery pack are connected to the positive and negative electrodes through aluminum or copper bars. Therefore, it is inevitable that there will be connection resistance. In the super fast charging state, the current is large, which makes the connection resistance generate more heat, thereby causing obvious gain interference to the top cover sampling. This part of the gain interference includes thermal radiation and heat conduction. Ultimately, the battery pack temperature collection value is higher than the actual value. In the non-super fast charging state, the charging current is relatively small. Although it will also cause gain interference, it is relatively much smaller and can be ignored.

[0047] Therefore, in this embodiment, in the super-fast charging state, it is necessary to calculate the battery temperature difference between the collected value and the actual value of the battery pack temperature. Specifically, it is necessary to first obtain the battery pack temperature, charging parameters, heat dissipation parameters, and battery pack cell parameters. Among them, the charging parameters include charging current, charging resistance, and charging time; the heat dissipation parameters include the ambient temperature and the coolant temperature in the thermal management system; the battery cell parameters include the battery cell weight and the battery cell specific heat capacity.

[0048] In this embodiment, the battery pack temperature is the temperature value of the battery pack obtained by sampling the top cover. In the super fast charging state, this value is larger than the actual value. The charging current is the current value of the battery pack charging in the super fast charging state. The charging resistance is mainly the internal resistance of the battery cell, excluding the connection resistance generated by the aluminum or copper bars connected to each battery cell. The charging time is the duration of the super fast charging state. The ambient temperature is the temperature of the environment in which the vehicle is located. The coolant temperature is the temperature of the coolant in the thermal management system of the battery pack. The specific heat capacity of the battery cell is a known and directly obtainable parameter, which is specifically related to the battery cell material.

[0049] In addition, it should be noted that this embodiment is only applicable to the super fast charging state. To determine whether it is in the super fast charging state, refer to the following steps:

[0050] If it is detected that the vehicle is connected to the charging pile, the maximum charging current and charging power of the charging pile are obtained;

[0051] If the maximum charging current of the charging pile reaches the fast charging current of the vehicle, and the charging power of the charging pile reaches the fast charging power of the vehicle, the vehicle is in a super fast charging state.

[0052] It is not difficult to understand that different charging piles can provide different maximum charging currents and charging powers. Only when the charging capacity of the charging pile meets the fast charging current and charging power required by the vehicle, can the vehicle be in the super fast charging state.

[0053] Step 102: Calculating a battery temperature difference generated by the connection resistance of the battery cells in the battery pack based on a preset energy formula for the connection resistance of each battery cell according to the battery pack temperature, the charging parameters, the heat dissipation parameters, and the battery cell parameters of the battery pack, wherein the energy formula is used to characterize the calculation of the battery temperature difference through the heat generation and heat dissipation of the battery pack, the heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters, the battery cell parameters of the battery pack, and the charging parameters, and the heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters, and a preset heat exchange coefficient;

[0054] In this embodiment, the battery temperature difference can be calculated based on the energy formula of energy conservation, and the energy formula is: battery pack heat generation=battery pack heat dissipation+battery stored heat.

[0055] Among them, the heat generated by the battery pack is mainly divided into two parts, one is the heat generated by the charging resistor, and the other is the gain heat generated by the connection resistor.

[0056] The heat generated by the charging resistor can be calculated based on the charging current, the charging resistor and the charging time. The specific formula is as follows:

[0057] Q1=I2 R

[0058] Among them, Q1 is the heat generated by the charging resistor, I is the charging current obtained in real time, R is the charging resistor, which can be obtained by looking up the internal resistance map table, and t is the charging time.

[0059] The gain heat generated by the connection resistance can be calculated based on the battery pack temperature, the charging current, the charging resistance, the charging time, the ambient temperature, the coolant temperature, the weight of the battery cell in the battery pack, and the specific heat capacity of the battery cell. The formula for the above variables can be derived through vehicle calibration experiments, and please refer to the subsequent content for details.

[0060] Finally, the sum of the heat generated by the charging resistor and the gain heat generated by the connection resistor is the heat generated by the battery pack.

[0061] When calculating the heat dissipation of the battery pack, it is necessary to pay attention to whether the thermal management system of the battery pack is turned on. Because when the thermal management system is turned on, the battery pack not only exchanges heat with the coolant in the thermal management system, but also exchanges heat with the air. When the thermal management system is not turned on, the battery pack only exchanges heat with the air.

[0062] In one embodiment, a first temperature threshold and a second temperature threshold are set, and combined with the battery pack temperature, it is determined whether the thermal management system of the battery pack needs to be turned on, wherein the first temperature threshold is greater than the second temperature threshold.

[0063] For example, if the battery pack temperature is greater than the first temperature threshold (for example, the first temperature threshold is 35 degrees), the thermal management system is turned on to cool the battery pack, the coolant temperature is 20 degrees, the flow rate is 20L / min, and the thermal management system is turned off when the battery pack temperature is less than or equal to 33 degrees; if the battery pack temperature is less than the second temperature threshold (for example, the first temperature threshold is 0 degrees), the thermal management system is turned on to heat the battery pack, the coolant temperature is 40 degrees, the flow rate is 20L / min, and the thermal management system is turned off when the battery pack temperature is greater than 5 degrees.

[0064] Therefore, when calculating the heat dissipation of the battery pack, if the coolant in the thermal management system does not generate heat exchange with the battery pack, the heat dissipation of the battery pack is calculated based on the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature and the ambient temperature. For details, refer to the following formula:

[0065] Q 散 =a1*h1*A1*△T1+b1

[0066] Among them, Q 散is the heat dissipation of the battery pack when the coolant in the thermal management system does not generate heat exchange with the battery pack, a1 is a constant coefficient, h1 is the heat exchange coefficient between the battery pack and the air, A1 is the contact area between the battery pack and the air, △T1 is the absolute difference between the battery pack temperature and the ambient temperature, and b1 is a constant.

[0067] If the coolant in the thermal management system generates heat exchange with the battery pack, the heat dissipation of the battery pack is calculated according to the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature, the ambient temperature, the heat exchange coefficient between the battery pack and the coolant, the contact area between the battery pack and the coolant, and the coolant temperature. For details, refer to the following formula:

[0068] Q 散 =a1*h1*A1*△T1+b1+a2*h2*A2*△T2+b2

[0069] Among them, Q 散 is the heat dissipation of the battery pack generated by heat exchange between the coolant in the thermal management system and the battery pack, a1 is a constant coefficient, h1 is the heat exchange coefficient between the battery pack and the air, A1 is the contact area between the battery pack and the air, △T1 is the absolute difference between the battery pack temperature and the ambient temperature, b1 is a constant, a2 is a constant coefficient, h2 is the heat exchange coefficient between the battery pack and the coolant, A2 is the contact area between the battery pack and the coolant, △T2 is the absolute difference between the battery pack temperature and the coolant temperature, and b2 is a constant.

[0070] Finally, the battery temperature difference is calculated according to the heat generation of the battery pack, the heat dissipation of the battery pack, the weight of the battery cell and the specific heat capacity of the battery cell.

[0071] Specifically, the heat stored in the battery pack is first determined based on the difference between the heat generated by the battery pack and the heat dissipated by the battery pack; wherein the heat stored in the battery pack refers to the heat absorbed by the actual temperature rise of the battery pack.

[0072] Then, the battery temperature difference is calculated according to the heat stored in the battery pack, the weight of the battery cell and the specific heat capacity of the battery cell. For details, please refer to the following formula:

[0073] Q 存 =cm*△T3

[0074] Among them, Q 存 is the heat stored in the battery pack, c is the specific heat capacity of the battery cell, m is the weight of the battery cell, and △T3 is the battery temperature difference.

[0075] It should be noted that the gain heat generated by the connection resistance needs to be measured by the vehicle calibration experiment on the battery pack, so as to be used to calculate the battery temperature difference △T3.

[0076] Specifically, the internal temperature of the battery cell is monitored by the specially made battery cell (the battery cell has a built-in sensor, which can be located at the upper tab of the battery cell, the middle of the battery cell, or the bottom of the battery cell), and the battery pack temperature detected by the temperature sensor on the aluminum shell of the battery pack is recorded as T_out. In the super fast charging state, T_out is greater than T_i n.

[0077] Gain heat generation Q 增 It is strongly related to the charging current and weakly related to the battery pack temperature. Through the battery pack bench test, △T3 can be calculated and substituted into the following formula to derive Q 增 The expression is:

[0078] cm*△T3=I 2 Q 增 -Q 散

[0079] Among them, △T3 is the battery temperature difference, which can be calculated from the difference between T_out and T_in, I is the charging current during the test, R is the charging resistance during the test, t is the charging time during the test, c is the specific heat capacity of the battery cell, m is the weight of the battery cell, Q 增 is the gain heat generation, Q 散 Dissipate heat for the battery pack.

[0080] The final test results are Q 增 When calculating the battery temperature difference, it is also necessary to meet the conditions of low temperature test (for example, minus 20 degrees) and static difference test, the calculated battery temperature difference is less than or equal to 8 degrees; under normal temperature test and high temperature difference test conditions, the calculated battery temperature difference is less than or equal to 5 degrees. 增 Only then can you be considered qualified.

[0081] Step 103: Correct the battery pack temperature according to the battery temperature difference to obtain a target battery pack temperature.

[0082] In this embodiment, after the battery temperature difference is calculated, the battery pack temperature can be corrected, specifically, the battery pack temperature is subtracted from the battery pack temperature to obtain the target battery pack temperature. The obtained target battery pack temperature is generally slightly lower than the battery pack temperature measured by the sensor.

[0083] In the super fast charging state, the target battery pack temperature is used to look up the table to determine the charging current. Since the target battery pack temperature is relatively low compared to the battery pack temperature, when looking up the table, the charging current corresponding to the target battery pack temperature may be greater than the charging current corresponding to the battery pack temperature, thereby improving the charging time of the battery pack.

[0084] To summarize, a battery pack temperature correction method provided in an embodiment of the present specification corrects the original battery pack temperature by calculating the battery temperature difference, so that the corrected target battery pack temperature is relatively lowered. In the super fast charging state, the charging current based on the target battery pack search may increase, thereby improving the charging speed of the battery pack.

[0085] Based on the same inventive concept, combined Figure 2 As shown, an embodiment of the present invention further provides a battery pack temperature correction device, comprising:

[0086] The acquisition module is used to obtain the battery pack temperature, charging current, charging resistance, charging time, ambient temperature, coolant temperature, battery cell weight in the battery pack, and battery cell specific heat capacity in the super fast charging state;

[0087] a calculation module, configured to calculate a battery temperature difference generated by the connection resistance of the battery cells in the battery pack according to the battery pack temperature, the charging parameters, the heat dissipation parameters and the battery cell parameters of the battery pack, based on a preset energy formula for the connection resistance of each battery cell, wherein the energy formula is used to characterize the calculation of the battery temperature difference through the heat generation and heat dissipation of the battery pack, the heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters, the battery cell parameters and the charging parameters, and the heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters and a preset heat exchange coefficient;

[0088] The correction module is used to correct the battery pack temperature according to the battery temperature difference to obtain a target battery pack temperature.

[0089] Optionally, the computing module is further used for:

[0090] Calculating heat generated by the charging resistor according to the charging current, the charging resistor and the charging time;

[0091] Calculate the gain heat generation of the connection resistance according to the battery pack temperature, the charging current, the charging resistance, the charging time, the ambient temperature, the coolant temperature, the weight of the battery cells in the battery pack, and the specific heat capacity of the battery cells;

[0092] The heat generation of the battery pack is determined according to the heat generation of the charging resistor and the gain heat generation of the connection resistor.

[0093] Optionally, the computing module is further used for:

[0094] If the coolant in the thermal management system generates heat exchange with the battery pack, the heat dissipation of the battery pack is calculated according to the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature, the ambient temperature, the heat exchange coefficient between the battery pack and the coolant, the contact area between the battery pack and the coolant, and the coolant temperature;

[0095] If the coolant in the thermal management system does not generate heat exchange with the battery pack, the heat dissipation of the battery pack is calculated based on the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature and the ambient temperature.

[0096] Optionally, the computing module is further used for:

[0097] If the battery pack temperature is greater than a first temperature threshold, or the battery pack temperature is less than a second temperature threshold, the thermal management system is turned on to allow the coolant in the thermal management system to exchange heat with the battery pack; wherein the first temperature threshold is greater than the second temperature threshold.

[0098] Optionally, the computing module is further used for:

[0099] Determining the amount of heat stored in the battery pack according to the difference between the heat generated by the battery pack and the heat dissipated by the battery pack;

[0100] The battery temperature difference is calculated according to the stored heat of the battery pack, the weight of the battery cell and the specific heat capacity of the battery cell.

[0101] Optionally, the acquisition module is also used to:

[0102] If it is detected that the vehicle is connected to the charging pile, the maximum charging current and charging power of the charging pile are obtained;

[0103] If the maximum charging current of the charging pile reaches the fast charging current of the vehicle, and the charging power of the charging pile reaches the fast charging power of the vehicle, the vehicle is in a super fast charging state.

[0104] Optionally, the correction module is also used to:

[0105] According to the target battery pack temperature, the charging current of the battery pack in the super fast charging state is adjusted.

[0106] To summarize, a battery pack temperature correction device provided in an embodiment of the present specification corrects the original battery pack temperature by calculating the battery temperature difference, so that the corrected target battery pack temperature is relatively lowered. In the super-fast charging state, the charging current based on the target battery pack search may increase, thereby improving the charging speed of the battery pack.

[0107] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the battery pack temperature correction device described above can refer to the corresponding process in the aforementioned method, and will not be elaborated here.

[0108] Based on the same inventive concept, an embodiment of the present invention also provides a controller, which includes a battery pack temperature correction device, a memory, a processor and a communication unit. The memory stores machine-readable instructions executable by the processor. When the controller is running, the processor and the memory communicate through a bus, the processor executes the machine-readable instructions, and executes the battery pack temperature correction method.

[0109] The memory, processor and communication unit components are electrically connected to each other directly or indirectly to achieve signal transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The battery pack temperature correction device includes at least one software function module that can be stored in the memory in the form of software or firmware. The processor is used to execute the executable module stored in the memory (such as the software function module or computer program included in the battery pack temperature correction device).

[0110] Among them, the memory can be, but is not limited to, random access memory (Random Access Memory, RAM), read-only memory (Read On ly Memory, ROM), programmable read-only memory (Programmable Read-Only Memory, PROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, EPROM), electrically erasable read-only memory (Electrical Erasable Programmable Read-Only Memory, EEPROM), etc.

[0111] In some embodiments, the processor is used to perform one or more functions described in this embodiment. In some embodiments, the processor may include one or more processing cores (eg, a single-core processor (S) or a multi-core processor (S)).

[0112] In this embodiment, the memory is used to store the program, and the processor is used to execute the program after receiving the execution instruction. The process definition method disclosed in any implementation of this embodiment can be applied to the processor, or implemented by the processor.

[0113] The communication unit is used to establish a communication connection between the controller and other devices through the network, and to send and receive data through the network.

[0114] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the controller described above can refer to the corresponding process in the aforementioned method, and will not be elaborated here.

[0115] Based on the same inventive concept, an embodiment of the present invention further provides a vehicle, including a vehicle body and a controller installed in the vehicle body, wherein the controller is used to implement the aforementioned battery pack temperature correction method.

[0116] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the controller of the vehicle described above can refer to the corresponding process in the aforementioned method, and will not be elaborated here.

[0117] The above are only various embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A battery pack temperature correction method, characterized in that: include: In the super-fast charging state, obtain the battery pack temperature, charging parameters, heat dissipation parameters, and battery pack cell parameters; According to the battery pack temperature, the charging parameters, the heat dissipation parameters and the battery cell parameters of the battery pack, based on a preset energy formula about the connection resistance of each battery cell, a battery temperature difference generated by the connection resistance of the battery cells in the battery pack is calculated, wherein the energy formula is used to characterize the calculation of the battery temperature difference through the heat generation and heat dissipation of the battery pack, the heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters, the battery cell parameters and the charging parameters, and the heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters and a preset heat exchange coefficient; The battery pack temperature is corrected according to the battery temperature difference to obtain a target battery pack temperature.

2. The method according to claim 1, characterized in that The charging parameters include charging current, charging resistance and charging time, the heat dissipation parameters include ambient temperature and coolant temperature in the thermal management system, and the battery cell parameters include battery cell weight and battery cell specific heat capacity; The heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameter, the cell parameter of the battery pack and the charging parameter, including: Calculating heat generated by the charging resistor according to the charging current, the charging resistor and the charging time; Calculate the gain heat generation of the connection resistance according to the battery pack temperature, the charging current, the charging resistance, the charging time, the ambient temperature, the coolant temperature, the weight of the battery cells in the battery pack, and the specific heat capacity of the battery cells; The heat generation of the battery pack is determined according to the heat generation of the charging resistor and the gain heat generation of the connection resistor.

3. The method according to claim 2, characterized in that The heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameter and a preset heat exchange coefficient, including: If the coolant in the thermal management system generates heat exchange with the battery pack, the heat dissipation of the battery pack is calculated according to the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature, the ambient temperature, the heat exchange coefficient between the battery pack and the coolant, the contact area between the battery pack and the coolant, and the coolant temperature; If the coolant in the thermal management system does not generate heat exchange with the battery pack, the heat dissipation of the battery pack is calculated based on the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature and the ambient temperature.

4. The method according to claim 3, characterized in that Before the step of calculating the heat dissipation of the battery pack according to the heat exchange coefficient between the battery pack and the air, the contact area between the battery pack and the air, the battery pack temperature, the ambient temperature, the heat exchange coefficient between the battery pack and the coolant, the contact area between the battery pack and the coolant, and the coolant temperature, if the coolant in the thermal management system generates heat exchange with the battery pack, the method further includes: If the battery pack temperature is greater than a first temperature threshold, or the battery pack temperature is less than a second temperature threshold, the thermal management system is turned on to allow the coolant in the thermal management system to exchange heat with the battery pack; wherein the first temperature threshold is greater than the second temperature threshold.

5. The method according to claim 3, characterized in that: The calculating the battery temperature difference generated by the connection resistance of the battery cells in the battery pack based on a preset energy formula for the connection resistance of each battery cell includes: Determining the amount of heat stored in the battery pack according to the difference between the heat generated by the battery pack and the heat dissipated by the battery pack; The battery temperature difference is calculated according to the stored heat of the battery pack, the weight of the battery cell and the specific heat capacity of the battery cell.

6. The method according to claim 1, characterized in that Before the step in the super fast charging state, the method further includes: If it is detected that the vehicle is connected to the charging pile, the maximum charging current and charging power of the charging pile are obtained; If the maximum charging current of the charging pile reaches the fast charging current of the vehicle, and the charging power of the charging pile reaches the fast charging power of the vehicle, the vehicle is in a super fast charging state.

7. The method according to claim 1, characterized in that The method further comprises: According to the target battery pack temperature, the charging current of the battery pack in the super fast charging state is adjusted.

8. A battery pack temperature correction device, characterized in that: include: The acquisition module is used to obtain the battery pack temperature, charging parameters, heat dissipation parameters, and battery cell parameters of the battery pack in the super fast charging state; a calculation module, configured to calculate a battery temperature difference generated by the connection resistance of the battery cells in the battery pack according to the battery pack temperature, the charging parameters, the heat dissipation parameters and the battery cell parameters of the battery pack, based on a preset energy formula for the connection resistance of each battery cell, wherein the energy formula is used to characterize the calculation of the battery temperature difference through the heat generation and heat dissipation of the battery pack, the heat generation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters, the battery cell parameters and the charging parameters, and the heat dissipation of the battery pack is obtained by the battery pack temperature, the heat dissipation parameters and a preset heat exchange coefficient; The correction module is used to correct the battery pack temperature according to the battery temperature difference to obtain a target battery pack temperature.

9. A controller, characterized in that: The controller includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the battery pack temperature correction method described in any one of claims 1 to 7 when executing the computer program.

10. A vehicle, characterized in that: The vehicle includes a vehicle body and a controller installed in the vehicle body, wherein the controller executes the battery pack temperature correction method described in any one of claims 1-7.

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