Thermal management control method and control system for energy storage system of vehicle power battery pack

Abstract

The invention relates to the technical field of automobile thermal management, in particular to a thermal management control method and system for an energy storage system of a power battery pack for an automobile. Comprising the steps of setting discharging time and charging time of an energy storage system; the temperature of a battery pack cell in the energy storage system and the current temperature in the cabin are collected within the preset time before the set discharging time and the set charging time; determining whether the air conditioner needs to be started or not based on the battery cell temperature, when it is determined that the air conditioner needs to be started, determining the air conditioner starting time and mode based on the battery cell temperature, the cabin temperature and the target temperature, and controlling the air conditioner to be started according to the determined mode when the starting time is determined, and the preset target temperature is reached when the energy storage system is discharged or charged. The control method is simple, the air conditioner in the energy storage system can be controlled in advance, and when the energy storage system starts to be charged or discharged, the battery pack in the energy storage system is in a good temperature environment.

Description

Technical Field

[0001] The present invention relates to the field of automotive thermal management technology, and in particular to a thermal management control method and control system for an automotive power battery pack energy storage system. Background Art

[0002] Energy storage system refers to a system that stores energy in a certain form through specific equipment and technology, and converts the stored energy back into electrical energy or other forms of energy for use when needed. Currently, a widely used energy storage system is the electric energy storage system, which integrates multiple electric energy storage devices to store electric energy and then supplies power to electrical equipment during special time periods.

[0003] Currently, many electric energy storage devices are battery packs. After the used battery packs on electric vehicles are removed, they can be used as energy storage devices in energy storage systems. These battery packs are connected to the power grid, charged by the power grid to store energy, and then supply power to electrical equipment. Using used car battery packs as energy storage devices can not only achieve the effect of waste utilization, but also further reduce the cost of energy storage systems and use costs, providing a new idea for the recycling of used battery packs.

[0004] For the application of this type of energy storage system, one very important point is that the temperature control of the battery pack needs to be considered during the application of the energy storage system. Too high temperature may cause the battery pack to catch fire, and too low temperature will affect the normal operation of the battery pack.

[0005] At present, the temperature control of energy storage systems is all regulated by ventilation units. There is a prior art called battery compartment ventilation system and temperature control method, device and medium that discloses an energy storage system with a ventilation system. The energy storage system includes a battery compartment for storing battery packs and a charging compartment for placing a charger. The battery compartment ventilation system includes an air inlet and an air outlet arranged on the charging compartment and a ventilation unit connecting the battery compartment and the charging compartment. The air inlet and the air outlet can be opened and closed, and the ventilation unit can be opened and closed and the flow direction can be adjusted. The energy storage system obtains the temperature inside the battery compartment and the charging compartment respectively, and controls the opening and closing of the air inlet, the air outlet and the ventilation unit and the air volume flow path according to the temperature inside the battery compartment and the charging compartment to achieve the purpose of regulating the temperature.

[0006] This structure and method has certain problems in practical application. This structure is a passive adjustment method, that is, the ventilation structure will only be activated when the temperature triggers the condition. But in fact, the energy storage system also needs to consider the temperature problem during its own charging and discharging process, especially the energy storage system in cold or hot areas. If the energy storage system is not temperature-controlled in advance, the energy storage system may be in an inappropriate temperature environment when charging or discharging. The low temperature environment will cause the energy storage system to charge slowly, seriously affecting the user experience, and the high temperature environment has safety hazards and is easy to cause fire during the discharge process. Therefore, there is an urgent need for a control solution that can adjust the temperature of the energy storage system in advance. Summary of the invention

[0007] The purpose of this application is to address the deficiencies of the above-mentioned background technology and to provide a thermal management control method and control system for a vehicle power battery pack energy storage system.

[0008] The technical solution of the present application is: a thermal management control method for a vehicle power battery pack energy storage system, comprising the following steps:

[0009] Set the discharge time and charging time of the energy storage system;

[0010] Collect the battery cell temperature in the energy storage system and the current cabin temperature at a preset time before the set discharge time and charging time;

[0011] Determine whether to turn on the air conditioner based on the battery cell temperature. When it is determined that the air conditioner needs to be turned on, determine the air conditioner turn-on time and mode based on the battery cell temperature, the cabin temperature and the target temperature, and control the air conditioner to turn on according to the determined mode when the turn-on time is determined, until the preset target temperature is reached when the energy storage system is discharging or charging;

[0012] The cell temperature refers to the minimum cell temperature and the maximum cell temperature in the battery pack.

[0013] According to a thermal management control method for a vehicle power battery pack energy storage system provided in the present application, the method for setting the discharge time and charging time of the energy storage system is: the starting time of the valley electricity price for connecting the energy storage system to the power grid is set as the charging time, and the starting time of the peak electricity price for connecting the energy storage system to the power grid is set as the discharge time.

[0014] According to a thermal management control method for a vehicle power battery pack energy storage system provided in the present application, the method for determining whether to turn on the air conditioner based on the battery cell temperature includes: if the minimum temperature of the battery cell does not exceed the first set temperature or the maximum temperature of the battery cell is not less than the fourth set temperature at a preset time, the air conditioner needs to be turned on, otherwise the air conditioner does not need to be turned on.

[0015] According to a thermal management control method for a vehicle power battery pack energy storage system provided in the present application, the method for determining the air-conditioning start-up mode based on the battery cell temperature, the cabin temperature and the target temperature includes: if the minimum temperature of the battery cell does not exceed the first set temperature at a preset time, the air-conditioning is turned on and set to a preheating mode; if the maximum temperature of the battery cell is not less than a fourth set temperature at a preset time, the air-conditioning is turned on and set to a precooling mode.

[0016] According to a thermal management control method for a vehicle power battery pack energy storage system provided by the present application, at a preset time, if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature of the cabin, there is no need to turn on the air conditioner; at a preset time, if the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature does not exceed the lower limit temperature of the cabin, there is no need to turn on the air conditioner; the first temperature is less than the second set temperature, less than the third set temperature, and less than the fourth set temperature.

[0017] According to a thermal management control method for a vehicle power battery pack energy storage system provided in the present application, when the energy storage system is in a charging state or a discharging state, if the minimum temperature of the battery cell does not exceed the first set temperature, the air conditioner is controlled to operate in a heating mode; when the energy storage system is in a charging state or a discharging state, if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the cabin upper limit temperature, the air conditioner heating is turned off.

[0018] According to a thermal management control method for a vehicle power battery pack energy storage system provided in the present application, when the energy storage system is in a charging state or a discharging state, if the maximum temperature of the battery cell is not less than a fourth set temperature, the air conditioner is controlled to operate in a cooling mode; when the energy storage system is in a charging state or a discharging state, if the maximum temperature of the battery cell is not greater than a third set temperature or the cabin temperature is not greater than the lower limit temperature of the cabin, the air conditioner cooling is turned off.

[0019] According to a thermal management control method for a vehicle power battery pack energy storage system provided in the present application, the difference between the maximum temperature of the battery cell and the minimum temperature of the battery cell is obtained. If the difference is greater than a first set difference, the air conditioner is controlled to turn on the internal circulation mode; when the difference is less than a second set difference, the air conditioner is controlled to turn off the internal circulation; the first set difference is greater than the second set difference.

[0020] The present application also provides a thermal management control system for a vehicle power battery pack energy storage system, wherein the control system operates according to any of the above-mentioned thermal management control methods for a vehicle power battery pack energy storage system, including:

[0021] A charge and discharge time setting module, which is used to set the discharge time and charge time of the energy storage system;

[0022] A temperature acquisition module, which is used to collect the temperature of the battery cells in the energy storage system and the current cabin temperature at a preset time before the set discharge time and charging time;

[0023] A first judgment module, which judges whether the air conditioner needs to be turned on based on the battery core temperature;

[0024] A second judgment module, the second judgment module is used to determine the air conditioning start time and mode based on the battery core temperature, the cabin temperature and the target temperature when it is determined that the air conditioning needs to be turned on;

[0025] A control module, the control module is used to control the air conditioner to start and operate according to the determined mode at the start time after determining the start time and mode of the air conditioner, until the preset target temperature is reached when the energy storage system is discharged or charged;

[0026] The cell temperature refers to the minimum cell temperature and the maximum cell temperature in the battery pack.

[0027] According to a thermal management control system of a vehicle power battery pack energy storage system provided in the present application, the charging and discharging time setting module is used to set the starting time of the valley electricity price of the energy storage system connected to the power grid as the charging time, and to set the starting time of the peak electricity price of the energy storage system connected to the power grid as the discharging time.

[0028] According to a thermal management control system of a vehicle power battery pack energy storage system provided in the present application, the first judgment module is used to make a judgment that the air conditioner needs to be turned on when the minimum temperature of the battery cell does not exceed the first set temperature or the maximum temperature of the battery cell is not less than the fourth set temperature within a preset time, otherwise it is used to make a judgment that the air conditioner does not need to be turned on.

[0029] According to a thermal management control system of a vehicle power battery pack energy storage system provided by the present application, the second judgment module is used to make a judgment that the air conditioner needs to be turned on as a preheating mode when the minimum temperature of the battery cell does not exceed the first set temperature within the preset time, and to make a judgment that the air conditioner needs to be turned on as a precooling mode when the maximum temperature of the battery cell is not less than the fourth set temperature within the preset time.

[0030] According to a thermal management control system of a vehicle power battery pack energy storage system provided by the present application, the second judgment module is used to judge that the air conditioner does not need to be turned on when the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature of the cabin at a preset time, and to judge that the air conditioner does not need to be turned on when the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature does not exceed the lower limit temperature of the cabin at a preset time; the first temperature is less than the second set temperature, less than the third set temperature, and less than the fourth set temperature.

[0031] According to a thermal management control system of a vehicle power battery pack energy storage system provided by the present application, the control module includes:

[0032] A first regulating module, the first regulating module is used to control the air conditioner to operate in a heating mode when the energy storage system is in a charging state or a discharging state and the minimum temperature of the battery cell does not exceed a first set temperature;

[0033] A second regulating module, the second regulating module is used to turn off the air conditioning heating when the energy storage system is in a charging state or a discharging state and the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the cabin upper limit temperature;

[0034] A third regulating module, the third regulating module is used to control the air conditioner to operate in a cooling mode when the energy storage system is in a charging state or a discharging state and the maximum temperature of the battery cell is not less than a fourth set temperature;

[0035] The fourth regulating module turns off the air conditioning refrigeration when the energy storage system is in a charging state or a discharging state and the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature is not greater than the cabin lower limit temperature.

[0036] According to a thermal management control system of a vehicle power battery pack energy storage system provided by the present application, the control module further includes:

[0037] A temperature difference acquisition module, wherein the temperature difference acquisition module is used to obtain the difference between the maximum temperature of the battery cell and the minimum temperature of the battery cell;

[0038] The fifth regulating module is used to control the air conditioner to turn on the internal circulation mode when the difference is greater than the first set difference, and to control the air conditioner to turn off the internal circulation when the difference is less than the second set difference; the first set difference is greater than the second set difference.

[0039] The advantages of the present application are as follows: 1. The present application can pre-control the temperature of the energy storage system. Whether before charging or discharging, it can preheat or pre-cool the energy storage system by temperature judgment in advance, so that the temperature of the energy storage system reaches the target temperature. When the energy storage system starts charging or discharging, it is in a good temperature range, which improves the working state of the energy storage system. It will not cause slow charging and discharging due to too low temperature, nor will it cause fire safety accidents due to too high temperature.

[0040] 2. The charging time and discharging time of the energy storage system set in this application are determined based on the valley electricity price time and peak electricity price time of the power grid. This determination method is very convenient and can achieve the effect of peak-valley arbitrage. After setting the charging time and discharging time, the degree of automation control is high and the economic benefits are good;

[0041] 3. This application determines whether the air conditioner needs to be turned on by measuring the minimum and maximum temperatures of the battery cells. This judgment mode is very simple. It only needs to obtain the temperature of the battery cells to accurately determine whether the air conditioner needs to be turned on. The control strategy is simple and efficient.

[0042] 4. This application sets the charging time and discharging time, and judges by the battery cell temperature before the charging time and discharging time. It can judge whether preheating or precooling operation is needed at the preset time. The control logic is simple and convenient, and the temperature can be controlled in advance, so that the battery pack is in a good temperature range when it starts working, ensuring efficient operation of charging or discharging, while ensuring the safety of the energy storage system;

[0043] 5. This application sets a mode in which the air conditioner does not need to be turned on. By setting the conditions in which the air conditioner does not need to be turned on, the air conditioner inside the energy storage system can be efficiently controlled to avoid energy waste;

[0044] 6. This application will also collect the battery cell temperature in real time when the energy storage system is in a charging or discharging state, and control the operation of the air conditioner through the battery cell temperature to ensure that the energy storage system can maintain the internal temperature within a suitable range in real time during operation, thereby ensuring the normal operation of the battery pack inside the energy storage system;

[0045] 7. The present application can also collect the temperature of the battery cells in the battery pack in real time, and control the air conditioner in real time through the temperature of the battery cells in the battery pack. When the air conditioner is not needed, the air conditioner can be turned off to avoid energy waste;

[0046] 8. This application can also collect the temperature difference of the battery cells in the battery pack in real time. By turning on the air conditioning internal circulation mode, it can solve the problem of large temperature difference of the battery cells, ensure that the temperature difference of the battery pack cells in the entire energy storage system is within an appropriate range, and avoid safety accidents;

[0047] 9. The present application also provides a thermal management control system for a vehicle power battery pack energy storage system. The control system of the present application can be integrated into the energy storage system as software to automatically control the air conditioning of the energy storage system, thereby improving the degree of automation of temperature control and regulation of the entire energy storage system.

[0048] The control method of the present application is simple and can control the air conditioning inside the energy storage system in advance, so that when the energy storage system starts charging or discharging, the battery pack inside the energy storage system is in a good temperature environment, ensuring the stable and safe operation of the battery pack in the energy storage system. DETAILED DESCRIPTION

[0049] The embodiments of the present application are described in detail below, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0050] In the description of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0051] The present application is further described in detail below in conjunction with the scheme and specific embodiments.

[0052] The present application relates to a thermal management control method for a vehicle power battery pack energy storage system. The control method of the present application is mainly used to perform temperature regulation and control on the energy storage system. The energy storage system of the present application stores a large number of battery packs. By setting the working time of the energy storage system and regulating the temperature inside the energy storage system before the energy storage system starts working, it is ensured that the energy storage system reaches a good temperature environment when it starts working. The battery pack inside the energy storage system is in a good temperature environment before starting working, which can avoid the problem of slow charging of the battery pack in a low temperature environment and the problem of fire of the battery pack in a high temperature environment, thereby improving the stability and safety of the operation of the energy storage system.

[0053] Specifically, a thermal management control method for a vehicle power battery pack energy storage system of the present application includes the following steps:

[0054] S1. Setting the discharge time and charge time of the energy storage system;

[0055] By setting the discharge time and charging time of the energy storage system, the energy storage system can be automatically controlled and managed. The discharge time of the energy storage system is the time for the energy storage device inside the energy storage system (i.e., the energy storage device such as the battery pack. The battery pack of the present application is the old battery pack removed from the vehicle. The battery pack is provided with a control module. The temperature of the battery cell of the battery pack can be collected in real time through the control module on the battery pack. The collected data is fed back to the control system of the energy storage system) to discharge outwards. The charging time of the energy storage system is the time for the power grid to charge the energy storage device inside the energy storage system.

[0056] For this application, the starting time of the valley electricity price of the energy storage system connected to the grid is the charging time, and the starting time of the peak electricity price of the energy storage system connected to the grid is the discharging time;

[0057] In this way, low-price electricity can be stored during valley electricity price periods, and discharged during peak electricity price periods, achieving the effect of peak-valley arbitrage. After setting the charging time and discharging time, the degree of automation control is high, and the economic benefits are good;

[0058] S2. Collect the temperature of the battery pack cells in the energy storage system and the current cabin temperature at a preset time before the set discharge time and charging time;

[0059] This application is to pre-regulate the temperature of the energy storage system. Therefore, it is necessary to collect the cabin temperature and battery cell temperature of the current energy storage system before the energy storage system starts working. By collecting the cabin temperature and battery cell temperature in advance, it is possible to determine in advance whether the temperature needs to be adjusted, that is, to make a judgment in advance;

[0060] S3, determining whether the air conditioner needs to be turned on based on the battery cell temperature, and when it is determined that the air conditioner needs to be turned on, determining the air conditioner turn-on time and mode based on the battery cell temperature, the cabin temperature and the target temperature, and controlling the air conditioner to turn on according to the determined mode when the turn-on time is determined, until the preset target temperature is reached when the energy storage system is discharging or charging;

[0061] The advance control of the temperature inside the energy storage system is mainly to regulate the temperature of the battery pack inside the energy storage system. It is to ensure that the battery pack in the energy storage system is in a good temperature environment when it starts working. Therefore, the temperature regulation control is performed by collecting the temperature of the battery pack cells;

[0062] Under normal circumstances, the temperature change per unit time after the air conditioner is turned on is certain. Therefore, by collecting the current cabin temperature and target temperature, the time required for temperature adjustment can be determined. Then, based on the set charging time or discharging time, the air conditioner turn-on time can be obtained.

[0063] The preset time is no later than the start time. The preset time is calculated based on the most extreme temperature in the area where the energy storage system is located. For example, if the local minimum temperature is -10°C, the temperature increases by 5°C within 1 hour when the air conditioning system turns on the heating mode, and the set target temperature is 20°C, then the preset time can be set to 6 hours, so as to ensure that sufficient temperature adjustment time is reserved at the preset time; similarly, preheating also uses the above mode to obtain the preset time;

[0064] The battery cell temperature in this application refers to the minimum temperature and maximum temperature of the battery cells in the battery pack.

[0065] In some embodiments of the present application, this embodiment optimizes the above-mentioned step S3, and the specific method of determining whether to turn on the air conditioner based on the battery cell temperature includes: if the minimum temperature of the battery cell does not exceed the first set temperature or the maximum temperature of the battery cell is not less than the fourth set temperature at the preset time, the air conditioner needs to be turned on, otherwise the air conditioner does not need to be turned on.

[0066] The first set temperature of this embodiment is 0°C, and the fourth set temperature is 25°C. In actual application, it is not limited to the above temperatures, and corresponding selections can be made according to actual needs. That is to say, when the energy storage system starts working, whether it is the preset time before the charging time or the discharging time, if the minimum cell temperature of the battery pack collected does not exceed the first set temperature, that is, less than or equal to 0°C, or the maximum cell temperature of the battery pack collected is not less than the fourth set temperature, that is, greater than or equal to 25°C, then the air conditioner must be turned on for temperature adjustment, and it is considered that this situation does not meet the normal working temperature of the battery pack in the energy storage system.

[0067] Furthermore, if the minimum temperature of the battery cell does not exceed the first set temperature at the preset time, the air conditioner is turned on and set to the preheating mode. That is to say, the minimum temperature of the battery cell collected at the preset time does not exceed the first set temperature, that is, less than or equal to 0°C, which proves that the battery cell temperature of the battery pack is low at this time, and the battery pack needs to be heated up. Therefore, the air conditioner is controlled to preheat, so that when the battery pack inside the energy storage system starts to work, the battery pack is heated to a suitable temperature range; if the maximum temperature of the battery cell is not less than the fourth set temperature at the preset time, that is, the maximum temperature of the battery cell is greater than or equal to 25°C, it proves that the battery cell temperature in the battery pack is too high at this time, and the battery pack needs to be cooled down, and the air conditioner is controlled to precool the battery pack.

[0068] In some other embodiments of the present application, this embodiment further optimizes the above step S3. The above embodiment describes the mode in which the air conditioner needs to be turned on, and this embodiment describes the mode in which the air conditioner does not need to be turned on. At the preset time, if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature of the cabin, there is no need to turn on the air conditioner; at the preset time, if the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature does not exceed the lower limit temperature of the cabin, there is no need to turn on the air conditioner; the first temperature is less than the second set temperature, less than the third set temperature, and less than the fourth set temperature.

[0069] The second set temperature of this embodiment is 5° C., and the third set temperature is 15° C.; the upper limit temperature in the cabin of this embodiment is 20° C., and the lower limit temperature in the cabin is 15° C. In actual application, it is not limited to the above temperatures, and corresponding selections can be made according to actual needs.

[0070] In actual application, at the preset time, if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature of the cabin, there is no need to turn on the air conditioner, that is, the minimum temperature of the battery cell is greater than or equal to 5°C, or the cabin temperature is greater than or equal to 20°C. At this time, the battery pack in the energy storage system is in a relatively good temperature environment, so there is no need to turn on the air conditioner; in this case, the minimum temperature of the battery cell and the cabin temperature are identified. Of course, when the battery cell temperature continues to rise, if the maximum temperature of the battery cell exceeds the fourth set temperature, it is necessary to turn on the pre-cooling mode. That is to say, the minimum temperature of the battery cell determines whether the air conditioner needs to be turned on within a certain temperature range, that is, the minimum temperature of the battery cell is greater than or equal to 5°C, and the maximum temperature of the battery cell is less than 25°C; in another case, at the preset time, if the maximum temperature of the battery cell is not greater than 15°C or the cabin temperature does not exceed 5°C, there is no need to turn on the air conditioner; in this case, the battery pack in the energy storage system corresponding to the battery cell is in a relatively good temperature environment, and there is no need to turn on the air conditioner for temperature control. Similarly, in this case, the control is based on the maximum temperature of the battery cell. When the minimum temperature of the battery cell is less than or equal to 0°C, the preheating mode will be turned on.

[0071] The above two situations are modes in which the air conditioner does not need to be turned on for temperature adjustment, that is, at the preset time, it is determined that there is no need to control and adjust the current energy storage system, and no pre-operation is required.

[0072] In a further embodiment of the present application, this embodiment also describes the temperature regulation control of the energy storage system in the working mode. When the energy storage system is in the working state, that is, when the energy storage system is in the charging state or the discharging state, if the minimum temperature of the battery cell does not exceed the first set temperature, it proves that the temperature of the battery pack is low at this time. If the battery pack is not heated, it may cause the battery pack to be in a low temperature working environment, affecting the charging or discharging efficiency. Therefore, the air conditioner is controlled to operate in the heating mode at this time; when the energy storage system is in the charging state or the discharging state, if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the cabin upper limit temperature, the air conditioning heating is turned off. That is to say, when the energy storage system is in the working state, the heating mode is turned on. When the internal heating of the energy storage system meets the above conditions, the air conditioner can be turned off.

[0073] Similarly, when the energy storage system is in a charging state or a discharging state, if the maximum temperature of the battery cell is not less than the fourth set temperature, the air conditioner is controlled to operate in a cooling mode. At this time, the temperature of the battery cell is too high. If it is not controlled in time, there is a risk of fire, so the air conditioner needs to be turned on for cooling mode operation; when the energy storage system is in a charging state or a discharging state, if the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature is not greater than the lower limit temperature of the cabin, the air conditioner is turned off for cooling. When the cooling demand is met, that is, when the battery cell or cabin temperature drops to the above situation, the air conditioner can be stopped.

[0074] In some other embodiments of the present application, this embodiment also mentions an air conditioning operation mode and an air conditioning internal circulation mode. The air conditioning internal circulation mode is used to perform internal circulation operation inside the energy storage system to reduce the temperature difference of the battery cells of the battery pack and make the temperature of the battery cells inside the energy storage system more balanced. Specifically, the difference between the maximum temperature of the battery cell and the minimum temperature of the battery cell is obtained. If the difference is greater than the first set difference, the air conditioner is controlled to turn on the internal circulation mode; when the difference is less than the second set difference, the air conditioner is controlled to turn off the internal circulation; the first set difference is greater than the second set difference.

[0075] In this embodiment, the first set difference is 8° C., and the second set difference is 5° C. In practical application, it is not limited to the above values ​​and can be selected according to actual needs.

[0076] In actual application: the starting time of the valley electricity price for connecting the energy storage system to the grid is the charging time, and the starting time of the peak electricity price for connecting the energy storage system to the grid is the discharging time; the battery cell temperature of the battery pack in the energy storage system and the current cabin temperature are collected at the preset time before the set discharge time and charging time; if the minimum temperature of the battery cell does not exceed the first set temperature or the maximum temperature of the battery cell is not less than the fourth set temperature at the preset time, the air conditioner needs to be turned on, otherwise it does not need to be turned on; if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature at the preset time, the air conditioner does not need to be turned on; if the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature does not exceed the lower limit temperature at the preset time, the air conditioner does not need to be turned on;

[0077] When the energy storage system is in working state, when the energy storage system is in charging state or discharging state, if the minimum temperature of the battery cell does not exceed the first set temperature, the air conditioner is controlled to operate in heating mode; when the energy storage system is in charging state or discharging state, if the minimum temperature of the battery cell is not less than the second set temperature or the temperature in the cabin is not less than the upper limit temperature in the cabin, the air conditioner heating is turned off; when the energy storage system is in charging state or discharging state, if the maximum temperature of the battery cell is not less than the fourth set temperature, the air conditioner is controlled to operate in cooling mode; when the energy storage system is in charging state or discharging state, if the maximum temperature of the battery cell is not greater than the third set temperature or the temperature in the cabin is not greater than the lower limit temperature in the cabin, the air conditioner cooling is turned off;

[0078] When the energy storage system is in working state, the difference between the maximum temperature of the battery cell and the minimum temperature of the battery cell is obtained. If the difference is greater than a first set difference, the air conditioner is controlled to turn on the internal circulation mode; when the difference is less than a second set difference, the air conditioner is controlled to turn off the internal circulation; the first set difference is greater than the second set difference.

[0079] In addition, the present application also provides a thermal management control system for a vehicle power battery pack energy storage system, including a charge and discharge time setting module, a temperature acquisition module, a first judgment module, a second judgment module and a control module, wherein the charge and discharge time setting module is used to set the discharge time and charging time of the energy storage system; the temperature acquisition module is used to collect the battery cell temperature of the battery pack in the energy storage system and the current cabin temperature at a preset time before the set discharge time and charging time; the first judgment module determines whether the air conditioner needs to be turned on based on the battery cell temperature; the second judgment module is used to determine the air conditioner start-up time and mode based on the battery cell temperature, cabin temperature and target temperature when it is determined that the air conditioner needs to be turned on; the control module is used to control the air conditioner to start and operate according to the determined mode at the start-up time after determining the air conditioner start-up time and mode, until the preset target temperature is reached when the energy storage system is discharging or charging; the battery cell temperature is the minimum temperature and maximum temperature of the battery cell in the battery pack.

[0080] The charging and discharging time setting module is used to set the starting time of the valley electricity price of the energy storage system connected to the power grid as the charging time, and set the starting time of the peak electricity price of the energy storage system connected to the power grid as the discharging time.

[0081] The first judgment module is used to judge whether the air conditioner needs to be turned on when the minimum temperature of the battery cell does not exceed the first set temperature or the maximum temperature of the battery cell is not less than the fourth set temperature within the preset time, otherwise it is used to judge whether the air conditioner does not need to be turned on.

[0082] The second judgment module is used to judge whether the air conditioner needs to be turned on in preheating mode when the minimum temperature of the battery cell does not exceed the first set temperature within the preset time, and to judge whether the air conditioner needs to be turned on in precooling mode when the maximum temperature of the battery cell is not less than the fourth set temperature within the preset time.

[0083] The second judgment module is used to judge that the air conditioner does not need to be turned on when the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature of the cabin at the preset time, and to judge that the air conditioner does not need to be turned on when the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature does not exceed the lower limit temperature of the cabin at the preset time; the first temperature is less than the second set temperature, less than the third set temperature, and less than the fourth set temperature.

[0084] The control module includes a first regulating module, a second regulating module, a third regulating module and a fourth regulating module. The first regulating module is used to control the air conditioner to operate in a heating mode when the energy storage system is in a charging state or a discharging state and the minimum temperature of the battery cell does not exceed the first set temperature; the second regulating module is used to turn off the air conditioning heating when the energy storage system is in a charging state or a discharging state and the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature in the cabin; the third regulating module is used to control the air conditioner to operate in a cooling mode when the energy storage system is in a charging state or a discharging state and the maximum temperature of the battery cell is not less than the fourth set temperature; the fourth regulating module turns off the air conditioning cooling when the energy storage system is in a charging state or a discharging state and the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature is not greater than the lower limit temperature in the cabin.

[0085] The control module also includes a temperature difference acquisition module and a fifth adjustment module. The temperature difference acquisition module is used to obtain the difference between the maximum temperature of the battery cell and the minimum temperature of the battery cell; the fifth adjustment module is used to control the air conditioner to turn on the internal circulation mode when the difference is greater than a first set difference, and to control the air conditioner to turn off the internal circulation when the difference is less than a second set difference; the first set difference is greater than the second set difference.

[0086] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application to be protected. The scope of protection claimed in the present application is defined by the attached claims and their equivalents.

Claims

1. A thermal management control method for a vehicle power battery pack energy storage system, characterized in that: The following steps are involved: Set the discharge time and charging time of the energy storage system; Collect the battery cell temperature in the energy storage system and the current cabin temperature at a preset time before the set discharge time and charging time; Determine whether to turn on the air conditioner based on the battery cell temperature. When it is determined that the air conditioner needs to be turned on, determine the air conditioner turn-on time and mode based on the battery cell temperature, the cabin temperature and the target temperature, and control the air conditioner to turn on according to the determined mode when the turn-on time is determined, until the preset target temperature is reached when the energy storage system is discharging or charging; The cell temperature refers to the minimum cell temperature and the maximum cell temperature in the battery pack.

2. A thermal management control method for a vehicle power battery pack energy storage system according to claim 1, characterized in that: The method for setting the discharge time and the charge time of the energy storage system is as follows: the start time of the valley electricity price of the energy storage system connected to the grid is the charge time, and the start time of the peak electricity price of the energy storage system connected to the grid is the discharge time.

3. The thermal management control method of a vehicle power battery pack energy storage system according to claim 1, characterized in that: The method for determining whether to turn on the air conditioner based on the battery cell temperature includes: if the minimum temperature of the battery cell does not exceed the first set temperature or the maximum temperature of the battery cell is not less than the fourth set temperature at a preset time, the air conditioner needs to be turned on, otherwise the air conditioner does not need to be turned on.

4. A thermal management control method for a vehicle power battery pack energy storage system as claimed in claim 3, characterized in that: The method for determining the air conditioning start-up mode based on the battery cell temperature, the cabin temperature and the target temperature includes: if the minimum temperature of the battery cell does not exceed the first set temperature at a preset time, the air conditioning is turned on and set to the preheating mode; if the maximum temperature of the battery cell is not less than the fourth set temperature at the preset time, the air conditioning is turned on and set to the precooling mode.

5. A thermal management control method for a vehicle power battery pack energy storage system as claimed in claim 4, characterized in that: At the preset time, if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the upper limit temperature of the cabin, there is no need to turn on the air conditioner; at the preset time, if the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature does not exceed the lower limit temperature of the cabin, there is no need to turn on the air conditioner; the first temperature is less than the second set temperature, which is less than the third set temperature, which is less than the fourth set temperature.

6. A thermal management control method for a vehicle power battery pack energy storage system according to claim 1, characterized in that: When the energy storage system is in a charging state or a discharging state, if the minimum temperature of the battery cell does not exceed the first set temperature, the air conditioner is controlled to operate in a heating mode; when the energy storage system is in a charging state or a discharging state, if the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the cabin upper limit temperature, the air conditioner heating is turned off.

7. A thermal management control method for a vehicle power battery pack energy storage system according to claim 1, characterized in that: When the energy storage system is in a charging state or a discharging state, if the maximum temperature of the battery cell is not less than a fourth set temperature, the air conditioner is controlled to operate in a cooling mode; when the energy storage system is in a charging state or a discharging state, if the maximum temperature of the battery cell is not greater than a third set temperature or the cabin temperature is not greater than a lower limit temperature in the cabin, the air conditioner cooling is turned off.

8. The thermal management control method of a vehicle power battery pack energy storage system according to claim 1, characterized in that: The difference between the maximum temperature of the battery cell and the minimum temperature of the battery cell is obtained. If the difference is greater than a first set difference, the air conditioner is controlled to turn on the internal circulation mode; when the difference is less than a second set difference, the air conditioner is controlled to turn off the internal circulation; the first set difference is greater than the second set difference.

9. A thermal management control system for a vehicle power battery pack energy storage system, characterized in that: The control system is operated according to any one of the thermal management control methods for a vehicle power battery pack energy storage system according to claims 1 to 8, including: A charge and discharge time setting module, which is used to set the discharge time and charge time of the energy storage system; A temperature acquisition module, which is used to collect the temperature of the battery cells in the energy storage system and the current cabin temperature at a preset time before the set discharge time and charging time; A first judgment module, which judges whether the air conditioner needs to be turned on based on the battery core temperature; A second judgment module, the second judgment module is used to determine the air conditioning start time and mode based on the battery core temperature, the cabin temperature and the target temperature when it is determined that the air conditioning needs to be turned on; A control module, the control module is used to control the air conditioner to start and operate according to the determined mode at the start time after determining the start time and mode of the air conditioner, until the preset target temperature is reached when the energy storage system is discharged or charged; The cell temperature refers to the minimum cell temperature and the maximum cell temperature in the battery pack.

10. A thermal management control system for a vehicle power battery pack energy storage system as claimed in claim 9, characterized in that: The control module comprises: A first regulating module, the first regulating module is used to control the air conditioner to operate in a heating mode when the energy storage system is in a charging state or a discharging state and the minimum temperature of the battery cell does not exceed a first set temperature; A second regulating module, the second regulating module is used to turn off the air conditioning heating when the energy storage system is in a charging state or a discharging state and the minimum temperature of the battery cell is not less than the second set temperature or the cabin temperature is not less than the cabin upper limit temperature; A third regulating module, the third regulating module is used to control the air conditioner to operate in a cooling mode when the energy storage system is in a charging state or a discharging state and the maximum temperature of the battery cell is not less than a fourth set temperature; The fourth regulating module turns off the air conditioning refrigeration when the energy storage system is in a charging state or a discharging state and the maximum temperature of the battery cell is not greater than the third set temperature or the cabin temperature is not greater than the cabin lower limit temperature.