Control method and device for adaptively adjusting overcharge current and vehicle

Abstract

The invention discloses a control method and device for adaptively adjusting overcharge current and a vehicle, and the method comprises the steps: obtaining the initial temperature of a battery cell of a battery pack and the initial electric quantity of the battery pack when a vehicle gun insertion charging signal is received; if the initial temperature of the battery cell is in a first temperature interval and the initial electric quantity is smaller than or equal to first preset electric quantity, cooling is carried out, the battery pack is charged according to a preset minimum current value, and when the charging duration is equal to first preset duration, a dynamic charging step is executed: the current temperature and the current residual electric quantity of the battery cell are obtained; controlling the operation state of the thermal management system according to the current temperature, determining a charging request current required by the battery pack according to the current temperature and the current residual electric quantity, and performing charging based on the charging request current to obtain the current residual electric quantity after charging; and repeatedly executing the dynamic charging step until the current residual electric quantity reaches the preset electric quantity. According to the method, the temperature rise problem of the battery pack in the overcharge process is effectively controlled.

Description

Technical Field

[0001] This invention relates to the field of battery thermal management technology, and in particular to a control method, device, and vehicle for adaptively adjusting supercharging current. Background Technology

[0002] With the increasing proportion of new energy vehicles, the charging efficiency of electric vehicles has become a major concern. Standard fast charging only supports a charging current of 250A, while super-fast charging offers a much higher current and is one way to save charging time. Supercharging stations support high-power outputs of 250kW and 350kW, both capable of providing currents exceeding 400A. For 800V platform vehicles supporting supercharging, 4C and 5C supercharging with high currents will become the market mainstream.

[0003] Supercharging offers a larger charging current, improving charging efficiency, but it also presents a more significant challenge—a substantial increase in thermal effects. During charging, even with continuous cooling by thermal management, the cell temperature will still rise, eventually triggering the BMS (Battery Management System) for battery protection. To prevent overheating, the charging current is forcibly reduced. For example, during fast charging, if the cell temperature reaches 50°C, battery protection is triggered, causing a sharp drop in the requested current. The fast charging MAP (Maximum Charge Method) table shows a current of 0.5C, thus extending the overall charging time of the electric vehicle. Summary of the Invention

[0004] This application provides an adaptive supercharging current control method, device, and vehicle that can adaptively adjust the charging current during supercharging and flexibly control the start-up timing of the thermal management system, effectively controlling the battery pack temperature rise during supercharging, avoiding charging interruptions caused by battery overheating, and shortening the charging time.

[0005] In a first aspect, the present invention provides the following technical solution through an embodiment of the present invention:

[0006] An adaptive supercharging current control method includes: upon receiving a vehicle charging signal, acquiring the initial temperature of the battery pack cells and the initial charge of the battery pack; if the initial temperature of the cells is within a first temperature range and the initial charge is less than a first preset charge, then activating the battery pack thermal management system for cooling and charging the battery pack according to a preset minimum current value; when the charging time is equal to the first preset time, executing the following dynamic charging steps: acquiring the current temperature of the cells and the current remaining charge of the battery pack; controlling the operating state of the thermal management system based on the current temperature of the cells, and determining the required charging request current for the battery pack based on the current temperature of the cells and the current remaining charge, charging based on the charging request current to obtain the current remaining charge after charging; repeating the dynamic charging steps until the current remaining charge reaches the preset charge, wherein the maximum value of the first temperature range is greater than the set temperature.

[0007] Preferably, the method further includes: if the initial temperature is in a second temperature range and the initial charge is less than a second preset charge, then the thermal management system is activated for cooling, and the inlet temperature in the thermal management system is detected as being at a target temperature; if it is at the target temperature, then after a second preset time, the battery pack is charged according to the dynamic charging steps, wherein the second preset charge is greater than the first preset charge, and the minimum value of the second temperature range is greater than the maximum value of the first temperature range.

[0008] Preferably, the method further includes: if the initial temperature is in a third temperature range or a fourth temperature range, then charging the battery pack according to the dynamic charging steps; wherein the maximum value of the third temperature range is less than the minimum value of the first temperature range, and the minimum value of the fourth temperature range is greater than the maximum value of the second temperature range.

[0009] Preferably, the first temperature range is [30℃, 40℃), the second temperature range is [40℃, 50℃), the third temperature range is [0℃, 30℃), and the fourth temperature range is [50℃, 55℃].

[0010] Preferably, the method further includes: if the initial temperature is in a first temperature range and the initial charge is greater than the first preset charge, or if the initial temperature is in a second temperature range and the initial charge is greater than the second preset charge, then the battery pack is charged according to the dynamic charging steps.

[0011] Preferably, determining the required charging current for the battery pack based on the current temperature of the battery cell and the current remaining charge includes: determining the required charging current for the battery pack by looking up a first preset relationship table based on the current temperature of the battery cell and the current remaining charge, wherein the first preset relationship table contains a mapping relationship between the current temperature of the battery cell, the current remaining charge, and the charging request current.

[0012] Preferably, the method further includes: if the initial temperature of the battery cell is in a fifth temperature range, then obtaining the ambient temperature of the vehicle; if the ambient temperature is less than a preset minimum temperature, then charging the battery pack according to the dynamic charging steps, and obtaining the current temperature of the battery cell during the charging process according to the dynamic charging steps; if the current temperature of the battery cell is greater than a preset safe temperature, then obtaining the current remaining charge of the battery pack; determining the required charging request current of the battery pack by looking up a second preset relationship table based on the current temperature of the battery cell and the current remaining charge, and charging based on the charging request current to obtain the current remaining charge after charging; repeating the dynamic charging steps until the current remaining charge reaches a preset charge, wherein the second preset relationship table contains a mapping relationship between the current temperature of the battery cell, the current remaining charge, and the charging request current, the dimensions of the first preset relationship table and the second preset relationship table correspond, and under the same combination of the current temperature and current remaining charge of the battery cell, the charging request current in the second preset relationship table is a preset multiple of the corresponding charging request current in the first preset relationship table, wherein the preset multiple is between 0 and 1.

[0013] Preferably, the method further includes: if the ambient temperature is greater than or equal to the preset minimum temperature, then charging the battery pack according to the dynamic charging steps.

[0014] Secondly, through an embodiment of the present invention, the present invention provides the following technical solution: A control device for adaptively adjusting supercharge current, comprising: The first acquisition module is used to acquire the initial temperature of the battery pack cells and the initial charge of the battery pack when it receives a vehicle charging signal. The first control module is configured to, if the initial temperature of the battery cell is within a first temperature range and the initial charge is less than or equal to a first preset charge, activate the battery pack thermal management system for cooling and charge the battery pack according to a preset minimum current value. When the charging time is equal to the first preset time, the module executes the following dynamic charging steps: The second acquisition module is used to acquire the current temperature of the battery cell and the current remaining power of the battery pack; The charging control module is used to control the operating state of the thermal management system according to the current temperature of the battery cell, and to determine the charging request current required by the battery pack according to the current temperature of the battery cell and the current remaining power, and to charge the battery based on the charging request current to obtain the current remaining power after charging; and to repeat the dynamic charging steps until the current remaining power reaches the preset power.

[0015] Thirdly, through one embodiment of the present invention, the following technical solution is provided: A vehicle includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the steps of the method described in any of the first aspects above.

[0016] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: The adaptive supercharging current adjustment control method provided in this invention, upon receiving a vehicle charging signal, first acquires the initial temperature of the battery pack cells and the initial charge level of the battery pack. If the initial temperature of the cells is within a first temperature range and the initial charge level is less than or equal to a first preset charge level, the battery pack thermal management system is activated for cooling, and the battery pack is charged according to a preset minimum current value. When the charging time equals the first preset time, the following dynamic charging steps are executed until the current remaining charge level reaches the preset charge level. This method utilizes the cell temperature and battery charge level to adaptively adjust the charging current during supercharging, maintaining the cell temperature within the optimal range and flexibly controlling the activation timing of the thermal management system. This effectively controls the battery pack temperature rise during supercharging, avoids charging pauses caused by battery overheating, shortens charging time, and improves the user experience. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of the adaptive supercharger current control method in an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the changing states of the thermal management inlet and outlet during the initial charging stage in an embodiment of the present invention. Figure 3 This is a schematic diagram of the control device for adaptively adjusting supercharge current in an embodiment of the present invention; Figure 4This is a schematic diagram of the vehicle structure in an embodiment of the present invention. Detailed Implementation

[0019] This application provides an adaptive supercharging current control method, device, and vehicle that can adaptively adjust the charging current during supercharging and flexibly control the start-up timing of the thermal management system, effectively controlling the battery pack temperature rise during supercharging, avoiding charging interruptions caused by battery overheating, and shortening the charging time.

[0020] The technical solution of this application embodiment is to solve the above-mentioned technical problems, and the general idea is as follows: An adaptive supercharging current control method includes: upon receiving a vehicle charging signal, acquiring the initial temperature of the battery pack cells and the initial charge of the battery pack; if the initial temperature of the cells is within a first temperature range and the initial charge is less than or equal to a first preset charge, activating the battery pack thermal management system for cooling and charging the battery pack according to a preset minimum current value; when the charging time is equal to the first preset time, executing the following dynamic charging steps: acquiring the current temperature of the cells and the current remaining charge of the battery pack; controlling the operating state of the thermal management system based on the current temperature of the cells, and determining the required charging request current for the battery pack based on the current temperature of the cells and the current remaining charge, charging based on the charging request current to obtain the current remaining charge after charging; repeating the dynamic charging steps until the current remaining charge reaches the preset charge, wherein the maximum value of the first temperature range is greater than the set temperature.

[0021] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0022] Firstly, the embodiments of the present invention provide an adaptive control method for adjusting supercharging current, specifically, as follows: Figure 1 As shown, the method includes the following steps S101 to S104: Step S101: Upon receiving the vehicle charging signal, obtain the initial temperature of the battery pack cells and the initial charge of the battery pack. Step S102: If the initial temperature of the battery cell is within a first temperature range and the initial charge is less than a first preset charge, then the battery pack thermal management system is activated for cooling, and the battery pack is charged according to a preset minimum current value. When the charging time is equal to the first preset time, the following dynamic charging steps are executed: Step S103: Obtain the current temperature of the battery cell and the current remaining power of the battery pack; Step S104: Based on the current temperature of the battery cell, control the operating state of the thermal management system, and based on the current temperature of the battery cell and the current remaining power, determine the charging request current required for the battery pack, and charge based on the charging request current to obtain the current remaining power after charging; repeat the dynamic charging step until the current remaining power reaches the preset power, wherein the maximum value of the first temperature range is greater than the set temperature.

[0023] It should be noted that the implementing entity of this application can be a battery management system (BMS). This application is mainly aimed at the supercharging scenario of vehicles, but it can also be applied to the standard charging scenario (charging current ≤250A).

[0024] This control method can read the vehicle's current ambient temperature, cell temperature, and remaining battery charge in real time.

[0025] As an alternative embodiment, the battery pack voltage can be monitored in real time during the dynamic charging process. Specifically, the maximum and minimum voltages of the battery pack can be obtained to determine whether both are within a reasonable range, and the voltage can be displayed. If they are not within a reasonable range, an alarm can be triggered.

[0026] In practice, after plugging in fast charging, the appropriate fast charging mode is selected based on the initial temperature of the battery pack cells and the initial charge level of the battery pack. Specifically, if the initial temperature of the cells is within the first temperature range (i.e., near the set temperature) and the initial charge level is less than the first preset charge level, it indicates that the battery is likely to trigger the 50°C current limiting (cell temperature reaches 50°C) during overcharging, and the first fast charging mode is executed. First, the battery pack thermal management system is activated for cooling, and the battery pack is charged according to the preset minimum current value. When the charging time is equal to the first preset time, the dynamic charging step is executed.

[0027] Preferably, the set temperature can be 30℃, 35℃, etc., and the first temperature range can be [30℃, 40℃); the first preset power can be between 60% and 70%, for example, 70%; the minimum current value can be the calibrated small current value (such as the current corresponding to 1C); the first preset duration can be 2 to 4 minutes, for example, 3 minutes or 4 minutes.

[0028] Specifically, after plugging in the charging gun, if it is determined that the battery pack meets the first fast charging mode, the battery pack thermal management system is activated to cool it down. In the first 3 minutes, it is charged with a small current corresponding to 1C, so that the thermal management water temperature has enough time to decrease and the cell temperature also drops a bit before normal overcharging begins. This can avoid excessive temperature rise of the battery pack and shorten the overall charging time. Then, the dynamic charging step (normal charging process) is executed.

[0029] It should be noted that the first preset duration here can be obtained based on the working condition test.

[0030] In a specific embodiment, controlling the operation of the thermal management system based on the current temperature of the battery cell can include: if the current temperature of the battery cell is greater than a cooling temperature threshold (e.g., 40°C), controlling the thermal management system to cool; if the current temperature of the battery cell is less than a heating temperature threshold (e.g., 10°C), controlling the thermal management system to heat. During the cooling process, if the current temperature of the battery cell is detected to be less than or equal to a first set temperature (e.g., 36°C), controlling the thermal management system to shut down. The first set temperature is equal to the cooling temperature threshold minus a set compensation value, and the set compensation value is a positive value, for example, between 3 and 5°C. This avoids frequent starting and stopping of the thermal management system to cool the battery cell. During the heating process, if the current temperature of the battery cell is detected to be greater than or equal to a second set temperature (e.g., 15°C), controlling the thermal management system to shut down. The second set temperature is equal to the heating temperature threshold plus the set compensation value. This avoids frequent starting and stopping of the thermal management system to heat the battery cell. This achieves normal start and stop of the thermal management system, maintaining the battery cell temperature within an optimal range.

[0031] As an example, if the current temperature of the battery cell is detected to be 42°C, cooling is performed; if the current temperature of the battery cell is detected to be cooled to 36°C, the thermal management system is shut down; if the current temperature of the battery cell is detected to be 8°C, heating is performed; if the current temperature of the battery cell is detected to be heated to 15°C, the thermal management system is shut down.

[0032] In a specific embodiment, determining the required charging current for the battery pack based on the current temperature and remaining charge of the battery cell may include: determining the required charging current for the battery pack by looking up a first preset relationship table based on the current temperature and remaining charge of the battery cell, wherein the first preset relationship table contains a mapping relationship between the current temperature, remaining charge, and charging current of the battery cell.

[0033] Table 1 below shows an example of the first preset relationship table: Table 1 First Preset Relationship Table

[0034] In Table 1, the first column represents the current temperature of the battery cell, and the first row represents the current remaining capacity of the battery pack. Table 1 reflects the optimal rate range in the fast charging MAP. Using the dynamic charging method in Table 1, the cell temperature can be maintained within the optimal range, thus avoiding cell overheating and reducing charging time compared to existing technologies. For example, if the current temperature of the battery cell is between [20℃, 30℃) and the current remaining capacity is between [50%, 60%), the required charging current for the battery pack is 2.23C, as shown in the table. The actual charging current (A) = battery capacity (Ah) × charging rate (C).

[0035] As an example, the battery pack cells can reach a maximum charge rate of 4C during overcharging. However, once the cell temperature reaches 50°C, battery protection is triggered. At this point, the requested current drops sharply, limiting the current to 0.5C. This results in an excessively long charging time, failing to utilize the cells' optimal charging performance. Adopting this method to adaptively adjust the fast charging current avoids current limiting during fast charging in high-temperature environments, preventing over-temperature faults when the battery pack reaches 50°C, and reducing charging time.

[0036] As another alternative implementation, for standard fast charging stations, i.e., charging current ≤250A, which is smaller than that of supercharging stations, the first fast charging mode can also be used, adaptively adjusting the charging current to charge with a small current of 1C for the first 3 minutes (which can be calibrated) after plugging in the charging gun, thereby shortening the charging time.

[0037] The method further includes: if the initial temperature is in the second temperature range and the initial power is less than the second preset power, then the thermal management system is started for cooling, and the inlet temperature in the thermal management system is detected as being at the target temperature. If the target temperature is reached, the battery pack will be charged according to the dynamic charging steps after a second preset time. The second preset charge is greater than the first preset charge, and the minimum value of the second temperature range is greater than the maximum value of the first temperature range.

[0038] Optionally, the second temperature range can be [40℃, 50℃), the second preset power level can be between 70% and 80%, for example, 75% or 80%; the target temperature can be between 22 and 26℃, for example, 24℃ or 25℃; and the second preset duration can be between 1 and 3 minutes, for example, 2 minutes, 2.5 minutes or 3 minutes.

[0039] Specifically, after plugging in the charging gun, if the initial temperature of the battery cell is between 40℃ and 50℃, and the initial charge level is less than 80%, then the second fast charging mode will be executed: The thermal management system is activated for cooling, controlling the temperature of the cooling water at the inlet of the thermal management system to drop to the target temperature. Once the water temperature is at the target temperature, the dynamic charging step is performed after a delay of 1 to 3 minutes. In this way, the temperature of the battery cell and the temperature of the cooling water are stabilized at the reduced temperature before normal charging, which can effectively avoid the problem of battery cell overheating during overcharging.

[0040] Specifically, if the initial temperature is in the first temperature range and the initial charge is greater than or equal to the first preset charge, or if the initial temperature is in the second temperature range and the initial charge is greater than or equal to the second preset charge, the battery pack is charged according to the dynamic charging steps.

[0041] For example, if the initial temperature of the battery cell is between 30-40℃ and the SOC is less than 70%, it is charged with a small current of 1C for the first 3 minutes (t1=3min), and then charged normally. If the charge is greater than or equal to 70%, it is charged normally throughout the entire process. The fast charging request current corresponding to this range is small, the heat generation is small, and it will not rise to 50℃.

[0042] The initial temperature is between 40-50℃, the SOC is less than 80%, and the advanced cooling port temperature is cooled to 25℃, or the cell temperature is cooled to 30℃. The time required depends on the current cell temperature. If the initial battery temperature is 45℃ and the cooling rate is 2℃ / min, the time will be approximately 7.5 minutes.

[0043] The method may further include: if the initial temperature is in the third temperature range (10-30) or the fourth temperature range (50-55), then the battery pack is charged according to the dynamic charging steps; wherein the maximum value of the third temperature range is less than the minimum value of the first temperature range, and the minimum value of the fourth temperature range is greater than the maximum value of the second temperature range.

[0044] Optionally, the third temperature range can be [10℃, 30℃), and the fourth temperature range can be [50℃, 55℃].

[0045] Specifically, after plugging in the charging gun, if the initial temperature of the battery cell is between [10℃, 30℃] or [50℃, 55℃], then regardless of the initial charge level, the third fast charging mode will be executed: charging the battery pack according to the dynamic charging steps.

[0046] When the initial temperature of the battery cell is between [10℃, 30℃), the temperature of the battery cell is in a relatively ideal state, so there is no need to perform pre-cooling treatment. The thermal management is controlled to start and stop normally, and the charging request current is determined according to the fast charging MAP (first preset relationship table).

[0047] When the initial temperature of the battery cell is between [50℃, 55℃], since the battery cell reaches a relatively high temperature at this time, the pre-cooling treatment is no longer considered, the thermal management is controlled to start and stop normally, and the charging request current is determined according to the first preset relationship table.

[0048] The method further includes: if the initial temperature of the battery cell is in the fifth temperature range, then obtaining the ambient temperature of the vehicle. If the ambient temperature is lower than the preset minimum temperature, the battery pack will be charged according to the dynamic charging steps, and the current temperature of the battery cells will be obtained during the dynamic charging process. If the current temperature of the battery cell is higher than the preset safe temperature, then obtain the current remaining power of the battery pack. Based on the current temperature and remaining charge of the battery cell, the required charging request current for the battery pack is determined by consulting the second preset relationship table. Charging is then performed based on the charging request current to obtain the current remaining charge. The dynamic charging steps are repeated until the current remaining charge reaches the preset charge level. The second preset relationship table contains the mapping relationship between the current temperature, current remaining charge, and charging request current of the battery cell. The dimensions of the first and second preset relationship tables correspond. Under the same combination of current temperature and current remaining charge of the battery cell, the charging request current in the second preset relationship table is a preset multiple of the corresponding charging request current in the first preset relationship table. The preset multiple is between 0 and 1.

[0049] Ambient temperature can refer to the ambient temperature at the location of the vehicle.

[0050] Optionally, the fifth temperature range can be [-20℃~10℃]; the preset minimum temperature can be between 8 and 12℃, for example, 10℃ or 12℃; the preset safe temperature can be between [38℃~42℃], for example, 40℃.

[0051] Specifically, after plugging in the charging gun, if the initial temperature of the battery cell is between -20℃ and 10℃, then it is determined whether the ambient temperature is less than 10℃. If so, charging is performed according to the dynamic charging steps: obtaining the current temperature of the battery cell and the current remaining charge of the battery pack; controlling the operation status of the thermal management system based on the current temperature of the battery cell, and determining the charging request current required by the battery pack based on the current temperature of the battery cell and the current remaining charge, charging is performed based on the charging request current, and the current remaining charge after charging is obtained; the dynamic charging steps are repeated until the current remaining charge reaches the preset charge.

[0052] During dynamic charging, the current temperature of the battery cell is acquired in real time. If the current temperature of the battery cell is greater than 40°C, the fourth fast charging mode is executed: based on the current temperature of the battery cell and the current remaining power, the charging request current required by the battery pack is determined by looking up the second preset relationship table.

[0053] Given the current temperature and remaining charge of the same battery cell, the charging request current in the second preset relationship table is a preset multiple of the corresponding charging request current in the first preset relationship table, where the preset multiple is between 0 and 1. For example, the preset multiple can be between 0.5 and 0.9, such as 0.7 or 0.8.

[0054] For example, taking the charging request current in the second preset relationship table as 80% of the corresponding charging request current in the first preset relationship table as an example, if the current temperature of the battery cell is 45℃ and the current remaining charge is 70%, then looking up the second preset table, the charging request current is 1.2C; if the current temperature of the battery cell is 50℃ and the current remaining charge is 90%, then looking up the second preset table, the charging request current is 0.264C. This achieves the goal of reducing the charging request current to 80% of the original required value.

[0055] As an example, if the cell temperature is <10℃ and the ambient temperature is <10℃, the initial stage of charging follows the dynamic charging steps. When the battery reaches the set charging end stage, charging proceeds according to a new dynamic charging method. In this case, thermal management cooling is not used; instead, the current is reduced to 80% of the original current to control the cell temperature rise. If the cell temperature is <10℃ and the ambient temperature is ≥10℃, the initial stage of charging proceeds normally, and cooling is also normal at the charging end. The entire process follows the fast charging MAP jump and normal charging thermal management.

[0056] Specifically, in low-temperature supercharging environments, the thermal management system typically involves a process of heating the battery cells, shutting off heating once the required cell temperature is reached, and cooling the cells during supercharging (i.e., heating-stopping heating-cooling). To improve charging efficiency and save charging time, when the ambient temperature is below 10°C (calibrable), the thermal management system completes heating, shuts off after reaching the threshold, and remains in a deactivated state without initiating cooling. At this point, the charging process is nearing its end, and the supercharging current is reduced to 80% of the original required value (calibrable) to prevent the cell temperature from rising too quickly, which could trigger a sudden drop in fast charging current when the temperature reaches 50°C. This method not only prevents the battery pack from overheating but also reduces energy loss due to thermal management and does not affect the fast charging process. In low-temperature environments, after supercharging is complete, the battery cells are at a high temperature, further reducing the energy loss caused by the thermal management system's heating function and improving the electric vehicle's driving range.

[0057] For ease of understanding, Table 2 below shows the correspondence between the initial temperature and initial charge of the battery cell and the fast charging mode: Table 2 Initial temperature, initial charge, and fast charging mode of the battery cell

[0058] In Table 2, the first row represents the initial charge of the battery pack, and the first column represents the initial temperature of the battery cells. After plugging in fast charging, different fast charging schemes are selected based on the initial temperature and initial charge (SOC value) of the battery cells. The fast charging current is adaptively adjusted to avoid current limiting during fast charging in high-temperature environments, prevent the battery pack from reporting an over-temperature fault at 50℃, shorten charging time, and extend battery life.

[0059] It should be noted that Table 2 provides examples of SOC values ​​and temperature ranges. The SOC values ​​and temperature ranges are related to the cell charging performance, fast charging MAP, and the thermal management scheme used. In other alternative embodiments, the SOC range and temperature range can be adapted.

[0060] For example, if the initial temperature of the battery cell is between 30℃ and 40℃, and the State of Charge (SOC) is less than 70%, it is charged with a small current of 1C for the first t1 (3 minutes), followed by normal charging. If the SOC is greater than or equal to 70%, it is charged normally throughout the entire process. This is because the fast charging request current corresponding to this range is small, generating less heat and preventing the temperature from rising to 50℃. If the initial temperature is between 40-50℃ and the SOC is less than 80%, the battery cell temperature is first cooled to 30℃, and the time required depends on the current battery cell temperature. As an example, if the initial temperature is 45℃ and the cooling rate is 2℃ / min, the cooling time is approximately 7.5 minutes.

[0061] Taking a 120Ah 100s lithium iron phosphate battery with a liquid cooling thermal management system as an example, overcharging experiments were conducted under three operating conditions: -10℃ low temperature, 25℃ normal temperature, and 45℃ high temperature. Data such as SOC value, cell temperature, charging request current, actual current value, thermal management operating status (time required for the inlet, outlet, and water temperatures to reach optimal levels, i.e., thermal equilibrium time), inlet temperature, and outlet temperature were collected under each condition. Processing the collected information yields the time t1 from the issuance of the thermal management cooling command to the achievement of the optimal thermal management effect. Here, t1 refers to the time required for the inlet to reach the target water temperature during cooling, and the time required for the inlet to reach the target water temperature during heating.

[0062] The temperature rise of battery cells at different temperatures under different charging current cycles and the corresponding charging time t2 for different temperature ranges were obtained. Data analysis showed that when the fast charging temperature reaches 50℃, the t2 value is relatively large, resulting in a longer total charging time. During supercharging, adaptive adjustment of the charging current, combined with the thermal management scheme adopted by the battery pack, can effectively shorten the charging time. Through these three operating condition tests, the temperature rise and corresponding charging time of battery cells under different temperatures and fast charging current requirements can be obtained.

[0063] like Figure 2As shown, from top to bottom, there are four relationship curves. The horizontal axis of relationship curve 1 is time, and the vertical axis is the insertion signal. The horizontal axis of relationship curve 2 is time, and the vertical axis is the thermal management request signal. The horizontal axis of relationship curve 3 is time, and the vertical axis is the outlet temperature. The horizontal axis of relationship curve 4 is time, and the vertical axis is the inlet temperature.

[0064] Under high-temperature conditions, when supercharging is initiated, the thermal management system sends a cooling request. The time required for the inlet temperature to drop from the current temperature to the target water temperature is 4.5 minutes, so t1 = 4.5 minutes. The thermal management system does not achieve its optimal cooling effect (this 4.5-minute time depends on the specific implementation plan of the thermal management system and should be calculated based on the plan used). If charging at a high current (4C) is performed at this time, the temperature rises extremely rapidly.

[0065] Furthermore, even with continuous cooling by thermal management during charging, the cell temperature will still rise, eventually triggering the BMS battery protection, reporting an over-temperature fault, and forcibly reducing the charging current, thus prolonging the overall charging time of the electric vehicle. This solution addresses this issue by utilizing the interaction between ambient temperature and thermal management functions to adaptively adjust the charging current during supercharging, maintaining the cell temperature within the optimal range of the fast charging MAP, thereby shortening the electric vehicle charging time and improving the user experience.

[0066] In summary, the adaptive supercharging current control method provided by the embodiments of the present invention can adaptively adjust the charging current during the supercharging process and flexibly control the start-up timing of the thermal management system, effectively controlling the battery pack temperature rise during the supercharging process, avoiding charging pauses caused by battery overheating, shortening the charging time, effectively solving the problem of long charging time, and improving user satisfaction.

[0067] Secondly, based on the same inventive concept, this embodiment provides a control device for adaptively adjusting the supercharge current, such as... Figure 3 As shown, it includes: The first acquisition module 401 is used to acquire the initial temperature of the battery pack cells and the initial charge of the battery pack when a vehicle charging signal is received. The first control module 402 is configured to, if the initial temperature of the battery cell is within a first temperature range and the initial charge is less than or equal to a first preset charge, activate the battery pack thermal management system for cooling and charge the battery pack according to a preset minimum current value. When the charging time is equal to the first preset time, the following dynamic charging steps are executed: The second acquisition module 403 is used to acquire the current temperature of the battery cell and the current remaining power of the battery pack; The charging control module 404 is used to control the operating state of the thermal management system according to the current temperature of the battery cell, and to determine the charging request current required by the battery pack according to the current temperature of the battery cell and the current remaining power, and to charge based on the charging request current to obtain the current remaining power after charging; and to repeat the dynamic charging steps until the current remaining power reaches the preset power.

[0068] As an optional embodiment, the device further includes: The second control module is used to start the thermal management system for cooling if the initial temperature is in the second temperature range and the initial charge is less than the second preset charge, and to detect whether the inlet temperature in the thermal management system is at the target temperature; if it is at the target temperature, the battery pack is charged according to the dynamic charging steps after a second preset time, wherein the second preset charge is greater than the first preset charge and the minimum value of the second temperature range is greater than the maximum value of the first temperature range.

[0069] As an optional embodiment, the device further includes: The third control module is used to charge the battery pack according to the dynamic charging steps if the initial temperature is in the third temperature range or the fourth temperature range; wherein the maximum value of the third temperature range is less than the minimum value of the first temperature range, and the minimum value of the fourth temperature range is greater than the maximum value of the second temperature range.

[0070] As an optional embodiment, the first temperature range is [30℃, 40℃), the second temperature range is [40℃, 50℃), the third temperature range is [0℃, 30℃), and the fourth temperature range is [50℃, 55℃].

[0071] As an optional embodiment, the device further includes: The fourth control module is used to charge the battery pack according to the dynamic charging steps if the initial temperature is in the first temperature range and the initial charge is greater than the first preset charge, or if the initial temperature is in the second temperature range and the initial charge is greater than the second preset charge.

[0072] As an optional embodiment, the charging control module 404 is specifically used to: determine the charging request current required by the battery pack by looking up a first preset relationship table based on the current temperature and current remaining power of the battery cell, wherein the first preset relationship table contains a mapping relationship between the current temperature, current remaining power of the battery cell and the charging request current.

[0073] As an optional embodiment, the device further includes: The fifth control module is used to obtain the ambient temperature of the vehicle if the initial temperature of the battery cell is within the fifth temperature range; if the ambient temperature is lower than the preset minimum temperature, the battery pack is charged according to the dynamic charging steps, and the current temperature of the battery cell is obtained during the charging process; if the current temperature of the battery cell is higher than the preset safe temperature, the current remaining capacity of the battery pack is obtained; based on the current temperature and current remaining capacity of the battery cell, the required charging request current of the battery pack is determined by looking up the second preset relationship table, and charging is performed based on the charging request current to obtain the current remaining capacity after charging; the dynamic charging steps are repeated until the current remaining capacity reaches the preset capacity. The second preset relationship table contains the mapping relationship between the current temperature of the battery cell, the current remaining capacity, and the charging request current. The dimensions of the first preset relationship table and the second preset relationship table correspond. Under the same combination of current temperature and current remaining capacity of the battery cell, the charging request current in the second preset relationship table is a preset multiple of the corresponding charging request current in the first preset relationship table, and the preset multiple is between 0 and 1.

[0074] As an optional embodiment, the device further includes a sixth control module, used to charge the battery pack according to a dynamic charging procedure if the ambient temperature is greater than or equal to a preset minimum temperature.

[0075] Each of the above modules can be implemented using software code, in which case they can be stored in the memory of the control device. Alternatively, each of the above modules can be implemented using hardware, such as integrated circuit chips.

[0076] The adaptive supercharging current control device provided in this embodiment of the invention has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the device embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0077] Thirdly, based on the same inventive concept, this embodiment provides a vehicle 500, such as... Figure 4 As shown, it includes: a memory 501, a processor 502, and a computer program 503 stored in the memory and executable on the processor. When the processor 501 executes the program, it implements the steps of the adaptive adjustment of supercharging current control method described in the first aspect above.

[0078] Since the vehicle described in this embodiment is the vehicle used to implement the adaptive supercharger current control method in the embodiments of this application, those skilled in the art can understand the specific implementation method and various variations of the vehicle in this embodiment based on the adaptive supercharger current control method described in the embodiments of this application. Therefore, how the vehicle implements the method in the embodiments of this application will not be described in detail here. Any vehicle used by those skilled in the art to implement the adaptive supercharger current control method in the embodiments of this application falls within the scope of protection of this application.

[0079] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0080] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A module that specifies the function in one or more boxes.

[0081] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction modules implemented in a process. Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0082] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1The steps of the function specified in one or more boxes.

[0083] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0084] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A control method for adaptively adjusting supercharging current, characterized in that, include: Upon receiving a vehicle charging signal, the system acquires the initial temperature of the battery pack cells and the initial charge level of the battery pack. If the initial temperature of the battery cell is within a first temperature range and the initial charge is less than a first preset charge, the battery pack thermal management system is activated for cooling, and the battery pack is charged according to a preset minimum current value. When the charging time is equal to the first preset time, the following dynamic charging steps are executed: Obtain the current temperature of the battery cell and the current remaining charge of the battery pack; Based on the current temperature of the battery cell, the operation state of the thermal management system is controlled, and based on the current temperature of the battery cell and the current remaining power, the required charging current for the battery pack is determined. Charging is performed based on the charging request current to obtain the current remaining power after charging. The dynamic charging steps are repeated until the current remaining power reaches the preset power, wherein the maximum value of the first temperature range is greater than the set temperature.

2. The adaptive supercharging current control method as described in claim 1, characterized in that, Also includes: If the initial temperature is within the second temperature range and the initial power is less than the second preset power, then the thermal management system is activated for cooling, and the inlet temperature in the thermal management system is checked to see if it is at the target temperature. If the target temperature is reached, the battery pack will be charged according to the dynamic charging steps after a second preset time period, wherein the second preset charge is greater than the first preset charge, and the minimum value of the second temperature range is greater than the maximum value of the first temperature range.

3. The adaptive supercharging current control method as described in claim 2, characterized in that, Also includes: If the initial temperature is in the third or fourth temperature range, the battery pack is charged according to the dynamic charging steps. The maximum value of the third temperature range is less than the minimum value of the first temperature range, and the minimum value of the fourth temperature range is greater than the maximum value of the second temperature range.

4. The adaptive supercharging current control method as described in claim 3, characterized in that, The first temperature range is [30℃, 40℃), the second temperature range is [40℃, 50℃), the third temperature range is [0℃, 30℃), and the fourth temperature range is [50℃, 55℃].

5. The adaptive supercharging current control method as described in claim 2, characterized in that, Also includes: If the initial temperature is within the first temperature range and the initial charge is greater than the first preset charge, or if the initial temperature is within the second temperature range and the initial charge is greater than the second preset charge, then the battery pack is charged according to the dynamic charging steps.

6. The adaptive supercharging current control method as described in claim 1, characterized in that, Determining the required charging current for the battery pack based on the current temperature of the battery cell and the current remaining charge includes: Based on the current temperature of the battery cell and the current remaining power, the charging request current required by the battery pack is determined by consulting a first preset relationship table, wherein the first preset relationship table contains the mapping relationship between the current temperature of the battery cell, the current remaining power, and the charging request current.

7. The adaptive supercharging current control method as described in claim 1, characterized in that, Also includes: If the initial temperature of the battery cell is in the fifth temperature range, then the ambient temperature of the vehicle is obtained. If the ambient temperature is lower than the preset minimum temperature, the battery pack is charged according to the dynamic charging steps. During the charging process according to the dynamic charging steps, the current temperature of the battery cell is obtained. If the current temperature of the battery cell is greater than the preset safe temperature, then the current remaining power of the battery pack is obtained; Based on the current temperature of the battery cell and the current remaining power, the required charging request current for the battery pack is determined by consulting a second preset relationship table. Charging is then performed based on the charging request current to obtain the current remaining power after charging. The dynamic charging step is repeated until the current remaining power reaches a preset power level. The second preset relationship table contains a mapping relationship between the current temperature of the battery cell, the current remaining power, and the charging request current. The dimensions of the first preset relationship table and the second preset relationship table correspond. Under the same combination of current temperature and current remaining power of the battery cell, the charging request current in the second preset relationship table is a preset multiple of the corresponding charging request current in the first preset relationship table. The preset multiple is between 0 and 1.

8. The control method for adaptively adjusting the supercharge current as described in claim 7, characterized in that, Also includes: If the ambient temperature is greater than or equal to the preset minimum temperature, the battery pack is charged according to the dynamic charging steps.

9. A control device for adaptively adjusting supercharging current, characterized in that, include: The first acquisition module is used to acquire the initial temperature of the battery pack cells and the initial charge of the battery pack when it receives a vehicle charging signal. The first control module is configured to, if the initial temperature of the battery cell is within a first temperature range and the initial charge is less than or equal to a first preset charge, activate the battery pack thermal management system for cooling and charge the battery pack according to a preset minimum current value. When the charging time is equal to the first preset time, the module executes the following dynamic charging steps: The second acquisition module is used to acquire the current temperature of the battery cell and the current remaining power of the battery pack; The charging control module is used to control the operating status of the thermal management system according to the current temperature of the battery cell, and to determine the charging request current required by the battery pack according to the current temperature of the battery cell and the current remaining power, and to charge the battery based on the charging request current to obtain the current remaining power after charging. Repeat the dynamic charging steps until the current remaining power reaches the preset power level.

10. A vehicle, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the steps of the method according to any one of claims 1-8.

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