Power battery pack condensation prediction and control device and method

Abstract

The present invention discloses a condensation prediction and control device and method for a power battery pack. The device collects and calculates the dew point temperature value inside the power battery pack at the next moment, collects and calculates the minimum temperature value inside the power battery pack at the same time, and compares the minimum temperature value inside the power battery pack with the dew point temperature value inside the power battery pack at the next moment. Then, a target temperature is generated and sent to the battery thermal management system. The minimum temperature of the coolant is adjusted to the target temperature so that the minimum temperature value inside the power battery pack is always greater than the dew point temperature value inside the power battery pack, thereby achieving early prediction and control and preventing the formation of condensation. When adjusting the minimum temperature of the coolant is ineffective, the battery management system generates a dehumidification command and sends it to the air conditioning system. The air conditioning system automatically starts and controls the ventilation valve to open, blowing dry air into the power battery pack through the air conditioning duct, lowering the dew point temperature inside the power battery pack, preventing the formation of condensation, and further ensuring the safety and reliability of the power battery pack.

Description

Technical Field

[0001] The present invention relates to the technical field of power batteries, and more specifically, to a device and method for predicting and controlling condensation generation inside a power battery pack. Background Art

[0002] In recent years, with the rapid development of the electric vehicle industry, the number of and demand for new energy vehicles in China has increased year by year. At the same time, fire accidents involving new energy vehicles have also increased year by year. As the safety of new energy vehicles continues to gain attention, the safety and reliability of power battery packs are also receiving increasing attention. As in-depth investigations into new energy vehicle fires continue, a possible cause of these accidents has been identified: water vapor, or even condensation, leading to abnormal arcing and short circuits in high-voltage components within the power battery pack.

[0003] Typically, power battery packs are equipped with waterproof and breathable valves, which play an important role in protecting the power battery pack from water, dust, and air pressure. However, these valves cannot prevent the ingress and egress of water vapor. During actual use, water vapor may enter the power battery pack through the waterproof and breathable valves and accumulate inside the power battery pack. Over time, the water vapor gradually gathers and develops into condensation, dripping onto high-voltage components, causing corrosion, insulation failure, and even safety issues such as short circuits and fires. Currently, there are a large number of detection and control technologies for condensation formation inside power battery packs. Most of them prevent condensation by detecting the dew point temperature and controlling the temperature and humidity inside the battery pack.

[0004] However, current technology only measures the dew point temperature inside the battery pack in real time and cannot predict subsequent dew point temperature changes. If the dew point temperature inside the power battery pack subsequently changes due to changes in the external temperature and humidity, condensation may occur before control actions are taken, seriously impacting the safety of the electric vehicle battery pack. Furthermore, since existing technology cannot prevent condensation by controlling the temperature and humidity inside the battery pack, it can only limit power output or cut off high voltage to ensure battery pack safety, seriously affecting the usability of the electric vehicle. Summary of the Invention

[0005] The purpose of the present invention is to overcome the defect of the prior art that condensation inside the power battery pack cannot be predicted in advance and reliably controlled, and to provide a power battery pack condensation prediction and control device and method for judging, warning and controlling whether condensation is generated inside the power battery pack, thereby improving the safety and reliability of the power battery pack.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A power battery pack condensation prediction and control device includes: a power battery pack, an air conditioning system, a battery management system, a battery thermal management system, and an embedded unit. The power battery pack is respectively provided with a temperature sensor, a humidity sensor, and a pressure sensor inside and outside. The power battery pack is connected to the air conditioning system via an air conditioning duct.

[0008] The ventilation valve is installed on the air conditioning duct and is controlled by the air conditioning system. The interior of the power battery pack is connected to the air conditioning system through the ventilation valve. The battery management system is connected to the air conditioning system, the battery thermal management system and the embedded unit respectively. The battery thermal management system is connected to the power battery pack. The temperature sensor, humidity sensor and pressure sensor are connected to the embedded unit respectively.

[0009] The battery thermal management system is used to collect and control the minimum coolant temperature and send the coolant minimum temperature data to the battery management system; the embedded unit is used to obtain the temperature, humidity and air pressure data of the internal and external environments of the power battery pack and calculate the dew point temperature inside the power battery pack at the next moment;

[0010] The battery management system is used to obtain the operating condition data of the power battery pack, calculate the minimum temperature inside the power battery pack, and compare the dew point temperature inside the power battery pack at the next moment with the minimum temperature inside the power battery pack and the maximum allowable operating temperature of the battery;

[0011] When the dew point temperature inside the power battery pack is lower than the maximum allowable operating temperature of the battery, the battery management system generates a target temperature and sends it to the battery thermal management system. The battery thermal management system adjusts the minimum coolant temperature according to the target temperature to prevent condensation.

[0012] When the dew point temperature inside the power battery pack at the next moment is greater than or equal to the maximum allowable operating temperature of the battery, the battery management system generates a dehumidification command and sends it to the air-conditioning system. The air-conditioning system starts automatically and controls the ventilation valve to open, blowing dry air into the power battery pack through the air-conditioning duct, thereby lowering the dew point temperature inside the power battery pack.

[0013] Furthermore, it also includes a waterproof and breathable valve, which is arranged on the power battery pack and communicates with the interior of the power battery pack.

[0014] A method for predicting and controlling condensation of a power battery pack, applied to the above-mentioned device for predicting and controlling condensation of a power battery pack, comprises the following steps:

[0015] S1: The temperature sensor, humidity sensor, and pressure sensor collect temperature, humidity, and air pressure data from the internal and external environments of the power battery pack and send them to the embedded unit, which calculates the dew point temperature of the internal and external environments of the power battery pack.

[0016] S2: The embedded unit compares the dew point temperature inside the power battery pack with the dew point temperature of the external environment, generates a set dew point temperature, and sends it to the battery management system;

[0017] S3: The battery thermal management system obtains the minimum coolant temperature and sends it to the battery management system. The battery management system compares the minimum temperature of each battery in the power battery pack with the minimum coolant temperature to generate a set minimum temperature.

[0018] S4: The battery management system compares the set dew point temperature with the maximum allowable operating temperature of the battery. If the set dew point temperature is lower than the maximum allowable operating temperature of the battery, the battery management system compares the set dew point temperature with the set minimum temperature to generate a target temperature and sends it to the battery thermal management system.

[0019] S5: The battery thermal management system adjusts the minimum coolant temperature according to the target temperature to control the temperature inside the power battery pack above the dew point temperature;

[0020] S6: When the set dew point temperature is greater than the maximum allowable operating temperature of the battery, the battery management system generates a dehumidification command and sends it to the air conditioning system. The air conditioning system starts automatically and controls the ventilation valve to open, blowing dry air into the power battery pack through the air conditioning duct, thereby lowering the dew point temperature inside the power battery pack.

[0021] Furthermore, in step S4, the set dew point temperature is compared with the set minimum temperature, including:

[0022] S41: When the set dew point temperature is lower than the set minimum temperature, the target temperature is determined according to the operating conditions of the power battery pack;

[0023] S42: When the set dew point temperature is greater than the set minimum temperature, the target temperature is determined according to the set dew point temperature and the operating conditions of the power battery pack.

[0024] Furthermore, the battery management system adjusts the minimum coolant temperature through the battery thermal management system according to the operating conditions of the power battery pack, so that the battery temperature is maintained within the allowable operating temperature of the battery.

[0025] Furthermore, a method for calculating the dew point temperature is built into the embedded unit, and the calculation method for the dew point temperature is applicable to the normal operating ambient temperature range of the electric vehicle.

[0026] Furthermore, the embedded unit obtains the temperature, humidity and air pressure data of the internal and external environments of the power battery pack, substitutes them into the dew point temperature calculation method, and calculates the real-time dew point temperature inside the power battery pack and the dew point temperature of the external environment respectively.

[0027] Furthermore, the embedded unit compares the dew point temperature of the external environment with the dew point temperature inside the power battery pack, and selects the higher temperature as the set dew point temperature, that is, the dew point temperature inside the power battery pack at the next moment.

[0028] Furthermore, the battery management system compares and calculates the lowest temperature of each battery in the power battery pack with the lowest temperature of the coolant, selects the lower temperature as the set minimum temperature, that is, the lowest temperature inside the power battery pack, and compares it with the dew point temperature inside the power battery pack at the next moment.

[0029] Furthermore, when the dew point temperature inside the power battery pack at the next moment is greater than the maximum allowable operating temperature of the battery, the battery management system generates a dehumidification command and sends it to the air-conditioning system. The air-conditioning system starts automatically and opens the ventilation valve. Dry air continuously flows into the power battery pack through the air-conditioning duct and the ventilation valve, lowering the dew point temperature inside the power battery pack and continuing until the dew point temperature drops to the allowable operating temperature of the battery.

[0030] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0031] 1. This invention takes into account the hysteresis of the mass and heat transfer processes between the interior of the power battery pack and the external environment. By collecting and calculating the dew point temperatures inside and outside the power battery pack, the higher temperature is selected as the next internal dew point temperature. Simultaneously, the minimum coolant temperature and the minimum battery temperature are collected and calculated, with the lower temperature selected as the minimum internal temperature of the power battery pack. After comparing the minimum internal temperature of the power battery pack with the next dew point temperature, the minimum coolant temperature is adjusted to the target temperature, ensuring that the minimum internal temperature of the power battery pack is always greater than the dew point temperature. This enables early prediction and control to prevent condensation.

[0032] 2. If adjusting the coolant's minimum temperature fails to keep the battery pack's internal minimum temperature above the dew point, or if the battery temperature cannot be maintained within the battery's allowable operating temperature range, the battery management system initiates a dehumidification operation, generating a dehumidification command and sending it to the air conditioning system. Upon receiving the dehumidification command, the air conditioning system automatically activates and controls the ventilation valve to open, blowing dry air through the air conditioning duct into the battery pack, lowering the dew point and preventing condensation. This process continues until the battery temperature remains within the battery's allowable operating temperature range and the battery pack's internal minimum temperature exceeds the dew point. This ensures that the battery temperature remains within the allowable operating temperature range and condensation is eliminated, further ensuring the battery pack's safety and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the structure of the power battery pack condensation prediction and control device of the present invention.

[0034] Figure 2 Schematic diagram of the flow chart of the method for predicting and controlling condensation of a power battery pack according to the present invention.

[0035] Description of Figure Numbers:

[0036] 1-Power battery pack; 2-Battery; 3-Coolant pipe; 4-Ventilation valve; 5-Air conditioning duct; 6-Air conditioning system; 7-Battery management system; 8-Battery thermal management system;

[0037] 9 - embedded unit; 10 - first temperature sensor; 11 - first humidity sensor; 12 - first pressure sensor; 13 - second temperature sensor; 14 - second humidity sensor; 15 - second pressure sensor; 16 - waterproof breathable valve. DETAILED DESCRIPTION

[0038] The power battery pack condensation prediction and control device and method of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0039] See also Figure 1 The present invention discloses a condensation prediction and control device for a power battery pack, including a power battery pack 1, a battery 2, a coolant pipe 3, a ventilation valve 4, an air conditioning duct 5, an air conditioning system 6, a battery management system 7, a battery thermal management system 8, an embedded unit 9, a first temperature sensor 10, a first humidity sensor 11, a first pressure sensor 12, a second temperature sensor 13, a second humidity sensor 14, a second pressure sensor 15 and a waterproof breathable valve 16.

[0040] The batteries 2 within the power battery pack 1 are connected to the battery thermal management system 8 via coolant pipes 3. The power battery pack 1 is connected to the air conditioning duct 5, which in turn is connected to the air conditioning system 6. A ventilation valve 4 is located on the air conditioning duct 5 and is controlled by the air conditioning system 6. The ventilation valve 4 connects the interior of the power battery pack 1 to the air conditioning system 6. The battery management system 7 is connected to the air conditioning system 6 and the battery thermal management system 8. The embedded unit 9 is connected to the battery management system 7, the first temperature sensor 10, the first humidity sensor 11, the first pressure sensor 12, the second temperature sensor 13, the second humidity sensor 14, and the second pressure sensor 15.

[0041] The first temperature sensor 10, first humidity sensor 11, and first pressure sensor 12 are located outside the power battery pack 1 and are used to collect information about the external ambient temperature, humidity, and gas pressure. The second temperature sensor 13, second humidity sensor 14, and second pressure sensor 15 are located inside the power battery pack 1 and are used to collect information about the internal temperature, humidity, and gas pressure of the power battery pack 1. A waterproof vent valve 16 is provided on the power battery pack 1 and communicates with the interior of the power battery pack 1.

[0042] Ventilation valve 4 connects the air conditioning duct 5 to the power battery pack 1, blowing dry air into the power battery pack 1 to prevent condensation. Air conditioning system 6 blows dry air into the air conditioning duct 5 when the battery thermal management system 8 cannot prevent condensation by adjusting the coolant's minimum temperature. Battery management system 7 can obtain operating condition data, such as the minimum temperature of battery cells 2 in the power battery pack 1, to calculate the minimum temperature inside the power battery pack 1.

[0043] Embedded unit 9 is used to obtain the temperature, humidity, and air pressure of the internal and external environments of power battery pack 1, calculate the dew point temperature inside power battery pack 1 at the next moment (i.e., the set dew point temperature), and send this data to battery management system 7. Battery thermal management system 8 is used to collect and control the minimum coolant temperature in coolant pipe 3 of power battery pack 1 and send this minimum coolant temperature data to battery management system 7. Battery management system 7 compares the minimum temperature of each battery cell in power battery pack 1 with the minimum coolant temperature to calculate the minimum temperature inside power battery pack 1 (i.e., the set minimum temperature).

[0044] The battery management system 7 compares and calculates the dew point temperature inside the power battery pack 1 at the next moment with the minimum temperature inside the power battery pack 1 and the maximum allowable battery operating temperature. If the dew point temperature inside the power battery pack 1 at the next moment is lower than the maximum allowable battery operating temperature, the battery management system 7 generates a target temperature and sends it to the battery thermal management system 8. The battery thermal management system 8 adjusts the minimum coolant temperature based on the target temperature to prevent condensation.

[0045] When the dew point temperature inside the power battery pack 1 is greater than or equal to the maximum allowable operating temperature of the battery, the battery management system 7 generates a dehumidification command and sends it to the air conditioning system 6. Upon receiving the dehumidification command, the air conditioning system 6 automatically activates and controls the ventilation valve 4 to open the air conditioning duct 5 leading to the power battery pack 1. Air enters the power battery pack 1 through the air conditioning duct 5, lowering the dew point temperature inside the power battery pack 1 and preventing condensation.

[0046] See also Figure 2 The present invention also discloses a method for predicting and controlling condensation of a power battery pack, which is applied to the above-mentioned device for predicting and controlling condensation of a power battery pack, and includes the following steps:

[0047] S1: The first temperature sensor 10, the first humidity sensor 11, the first pressure sensor 12, the second temperature sensor 13, the second humidity sensor 14 and the second pressure sensor 15 collect the temperature, humidity and air pressure of the external environment and the inside of the power battery pack 1, and send them to the embedded unit 9. The embedded unit 9 calculates the dew point temperature inside the power battery pack 1 and the external environment respectively.

[0048] S2: The embedded unit 9 compares the dew point temperature inside the power battery pack 1 with the dew point temperature of the external environment, selects the higher temperature to generate the set dew point temperature (i.e. the dew point temperature inside the power battery pack 1 at the next moment), and sends it to the battery management system 7.

[0049] S3: The battery thermal management system 8 obtains the minimum temperature of the coolant and sends it to the battery management system 7. The battery management system 7 compares the minimum temperature of each battery in the power battery pack 1 with the minimum temperature of the coolant, selects the lower temperature and generates a set minimum temperature (i.e., the minimum temperature inside the power battery pack 1).

[0050] S4: The battery management system 7 compares the set dew point temperature with the maximum allowable operating temperature of the battery. When the set dew point temperature is lower than the maximum allowable operating temperature of the battery, the set dew point temperature is compared and calculated with the set minimum temperature to generate a target temperature and send it to the battery thermal management system 8.

[0051] S5: The battery thermal management system 8 adjusts the minimum temperature of the coolant according to the target temperature, and controls the temperature inside the power battery pack 1 to be above the dew point temperature to prevent condensation.

[0052] S6: When the set dew point temperature is greater than the maximum allowable operating temperature of the battery, the battery management system 7 will perform a dehumidification operation, generate a dehumidification instruction and send it to the air-conditioning system 6. After receiving the dehumidification instruction, the air-conditioning system 6 will automatically start and control the ventilation valve 4 to open, blowing dry air into the power battery pack 1 through the air-conditioning duct 5, thereby lowering the dew point temperature inside the power battery pack 1 and preventing the formation of condensation.

[0053] In step S4, the set dew point temperature is compared with the set minimum temperature and calculated, including: when the set dew point temperature is lower than the set minimum temperature, the target temperature is determined according to the operating conditions of the power battery pack 1; when the set dew point temperature is higher than the set minimum temperature, the target temperature is determined according to the set dew point temperature and the operating conditions of the power battery pack 1.

[0054] Based on the operating conditions of the power battery pack 1, the battery management system 7 regulates the minimum coolant temperature via the battery thermal management system 8 to maintain the battery temperature within the allowable operating temperature range. The embedded unit 9 includes a built-in dew point temperature calculation method, which is applicable to the normal operating temperature range of electric vehicles. The embedded unit 9 uses the acquired temperature, humidity, and air pressure data from both the internal and external environments of the power battery pack 1 and substitutes them into the dew point temperature calculation method to calculate the real-time dew point temperature inside the power battery pack 1 and the external dew point temperature.

[0055] When the dew point temperature inside the power battery pack 1 at the next moment is greater than the maximum allowable operating temperature of the battery, the battery management system 7 generates a dehumidification command and sends it to the air-conditioning system 6. The air-conditioning system 6 starts automatically and opens the ventilation valve 4. Dry air continuously flows into the power battery pack 1 through the air-conditioning duct 5 and the ventilation valve 4, lowering the dew point temperature inside the power battery pack 1 and continuing until the dew point temperature drops to the allowable operating temperature of the battery.

[0056] The air conditioning system 6 automatically activates upon receiving a dehumidification command from the battery management system 7, without requiring control from the passenger compartment. The dew point temperature can be calculated using a preset relative humidity and dew point temperature matrix, a preset parameter mapping relationship, or by fitting an empirical formula to a mathematical equation, without limitation in the present invention.

[0057] The battery management system 7 sends the dehumidification command to the air conditioning system 6 via the integrated circuit bus. The battery thermal management system 8 sends the operating condition data of the power battery pack 1 to the battery management system 7 via the integrated circuit bus. The embedded unit 9 sends the dew point temperature data of the power battery pack 1 at the next moment to the battery management system 7 via the integrated circuit bus.

[0058] During operation, the internal temperature and humidity of the power battery pack 1 change with the operating conditions and also with the external ambient temperature and humidity. Due to the heat and mass transfer characteristics of the waterproof vent valve 16, the temperature and humidity changes within the power battery pack 1 have a certain hysteresis. When the external ambient temperature and humidity change significantly, the first temperature sensor 10, the first humidity sensor 11, and the first pressure sensor 12 pre-measure the external ambient temperature and humidity data and calculate the external ambient dew point temperature. When the external ambient dew point temperature rises, the external ambient dew point temperature is used as the next dew point temperature within the power battery pack 1. This allows for the prediction of the dew point temperature and enables proactive response measures.

[0059] By default, the air conditioning system 6 will only blow air into the passenger compartment. That is, the ventilation valve 4 will, by default, close the air conditioning duct that blows toward the power battery pack 1. When the battery management system 7 issues a dehumidification command, if the air conditioning system 6 is in the off state, it will automatically start up and control the ventilation valve 4 to close the air conditioning duct that blows toward the passenger compartment. In this case, the air conditioning system 6 will only blow air toward the power battery pack 1. If the air conditioning system 6 is in the on state, it will directly control the ventilation valve 4 to open the air conditioning duct 5 leading to the power battery pack 1. In this case, the air conditioning system 6 will blow air into both the passenger compartment and the power battery pack 1 simultaneously to perform a dehumidification operation.

[0060] In summary, the present invention uses the first temperature sensor 10, first humidity sensor 11, first pressure sensor 12, second temperature sensor 13, second humidity sensor 14, and second pressure sensor 15 to collect real-time temperature, humidity, and air pressure data from inside and outside the power battery pack 1, and transmits these data to the embedded unit 9. The embedded unit 9 calculates the dew point temperature data inside the power battery pack 1 at the next instant, generates a set dew point temperature, and transmits this data to the battery management system 7.

[0061] The battery management system 7 obtains the coolant's minimum temperature from the battery thermal management system 8 and compares it with the battery's minimum temperature to generate a set minimum temperature. Based on the comparison between the set dew point temperature and the set minimum temperature, the battery management system 7 sends a target temperature to the battery thermal management system 8 or a dehumidification instruction to the air conditioning system 6. The battery thermal management system 8 controls the coolant's minimum temperature based on the target temperature, or the air conditioning system 6 performs a dehumidification operation based on the dehumidification instruction. This helps predict and avoid condensation in advance, thereby improving the safety of the power battery pack 1.

[0062] The above description is a detailed description of the preferred embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. Any equivalent changes or modifications made under the technical spirit disclosed by the present invention should fall within the patent scope covered by the present invention.

Claims

1. A power battery pack condensation prediction and control device, characterized in that: include: Power battery pack, air conditioning system, battery management system, battery thermal management system and embedded unit. The power battery pack is equipped with temperature sensors, humidity sensors and pressure sensors inside and outside respectively. The power battery pack and air conditioning system are connected through the air conditioning duct; The ventilation valve is installed on the air conditioning duct and is controlled by the air conditioning system. The interior of the power battery pack is connected to the air conditioning system through the ventilation valve. The battery management system is connected to the air conditioning system, the battery thermal management system and the embedded unit respectively. The battery thermal management system is connected to the power battery pack. The temperature sensor, humidity sensor and pressure sensor are connected to the embedded unit respectively. The battery thermal management system is used to collect and control the minimum coolant temperature and send the coolant minimum temperature data to the battery management system; The embedded unit is used to obtain temperature, humidity, and air pressure data from the internal and external environments of the power battery pack and calculate the dew point temperature inside the power battery pack at the next moment; Specifically, the embedded unit calculates the dew point temperature inside the power battery pack and the external environment respectively. The embedded unit compares the dew point temperature inside the power battery pack with the dew point temperature of the external environment, selects the higher temperature to generate the set dew point temperature, that is, the dew point temperature inside the power battery pack at the next moment, and sends it to the battery management system; The battery management system is used to obtain the operating condition data of the power battery pack and calculate the minimum temperature inside the power battery pack. Specifically, the battery management system compares the minimum temperature of each battery in the power battery pack with the minimum temperature of the coolant, selects the lower temperature and generates the set minimum temperature, that is, the minimum temperature inside the power battery pack. The battery management system also compares and calculates the dew point temperature inside the power battery pack at the next moment with the minimum temperature inside the power battery pack and the maximum allowable operating temperature of the battery. When the dew point temperature inside the power battery pack is lower than the maximum allowable operating temperature of the battery, the battery management system generates a target temperature and sends it to the battery thermal management system. The battery thermal management system adjusts the minimum coolant temperature according to the target temperature to prevent condensation. When the dew point temperature inside the power battery pack at the next moment is greater than or equal to the maximum allowable operating temperature of the battery, the battery management system generates a dehumidification command and sends it to the air-conditioning system. The air-conditioning system starts automatically and controls the ventilation valve to open, blowing dry air into the power battery pack through the air-conditioning duct, thereby lowering the dew point temperature inside the power battery pack.

2. The power battery pack condensation prediction and control device according to claim 1, characterized in that: It also includes a waterproof and breathable valve, which is arranged on the power battery pack and communicates with the interior of the power battery pack.

3. A method for predicting and controlling condensation of a power battery pack, characterized in that: The condensation prediction and control device for a power battery pack according to claim 1 or 2 comprises the following steps: S1: The temperature sensor, humidity sensor, and pressure sensor collect temperature, humidity, and air pressure data from the internal and external environments of the power battery pack and send them to the embedded unit, which calculates the dew point temperature of the internal and external environments of the power battery pack. S2: The embedded unit compares the dew point temperature inside the power battery pack with the dew point temperature of the external environment, generates a set dew point temperature, and sends it to the battery management system; S3: The battery thermal management system obtains the minimum coolant temperature and sends it to the battery management system. The battery management system compares the minimum temperature of each battery in the power battery pack with the minimum coolant temperature to generate a set minimum temperature. S4: The battery management system compares the set dew point temperature with the maximum allowable operating temperature of the battery. If the set dew point temperature is lower than the maximum allowable operating temperature of the battery, the battery management system compares the set dew point temperature with the set minimum temperature to generate a target temperature and sends it to the battery thermal management system. S5: The battery thermal management system adjusts the minimum coolant temperature according to the target temperature to control the temperature inside the power battery pack above the dew point temperature; S6: When the set dew point temperature is greater than the maximum allowable operating temperature of the battery, the battery management system generates a dehumidification command and sends it to the air conditioning system. The air conditioning system starts automatically and controls the ventilation valve to open, blowing dry air into the power battery pack through the air conditioning duct, thereby lowering the dew point temperature inside the power battery pack.

4. The power battery pack condensation prediction and control method according to claim 3, characterized in that: In step S4, the set dew point temperature is compared with the set minimum temperature, including: S41: When the set dew point temperature is lower than the set minimum temperature, the target temperature is determined according to the operating conditions of the power battery pack; S42: When the set dew point temperature is greater than the set minimum temperature, the target temperature is determined according to the set dew point temperature and the operating conditions of the power battery pack.

5. The power battery pack condensation prediction and control method according to claim 4, characterized in that: The battery management system adjusts the minimum coolant temperature through the battery thermal management system according to the operating conditions of the power battery pack, so that the battery temperature is maintained within the allowable operating temperature of the battery.

6. The power battery pack condensation prediction and control method according to claim 3, characterized in that: The calculation method of the dew point temperature is built into the embedded unit. The calculation method of the dew point temperature is applicable to the normal operating ambient temperature range of electric vehicles.

7. The power battery pack condensation prediction and control method according to claim 6, characterized in that: The embedded unit obtains the temperature, humidity and air pressure data of the internal and external environments of the power battery pack, substitutes them into the dew point temperature calculation method, and calculates the real-time dew point temperature inside the power battery pack and the dew point temperature of the external environment respectively.

8. The power battery pack condensation prediction and control method according to claim 7, characterized in that: The embedded unit compares the dew point temperature of the external environment with the dew point temperature inside the power battery pack, and selects the higher temperature as the set dew point temperature, which is the dew point temperature inside the power battery pack at the next moment.

9. The power battery pack condensation prediction and control method according to claim 8, characterized in that: The battery management system compares and calculates the lowest temperature of each battery in the power battery pack with the lowest temperature of the coolant, selects the lower temperature as the set minimum temperature, that is, the lowest temperature inside the power battery pack, and compares it with the dew point temperature inside the power battery pack at the next moment.

10. The power battery pack condensation prediction and control method according to claim 9, characterized in that: When the dew point temperature inside the power battery pack at the next moment is greater than the maximum allowable operating temperature of the battery, the battery management system generates a dehumidification command and sends it to the air-conditioning system. The air-conditioning system starts automatically and opens the ventilation valve. Dry air continuously flows into the power battery pack through the air-conditioning duct and the ventilation valve, lowering the dew point temperature inside the power battery pack and continuing until the dew point temperature drops to the allowable operating temperature of the battery.

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