Heat management method and device of liquid cooling energy storage system and electronic equipment

Abstract

The invention discloses a thermal management method and device for a liquid cooling energy storage system and electronic equipment, and belongs to the technical field of energy storage systems, and the method comprises the steps: obtaining the temperature value of each single battery in a battery stack corresponding to any liquid cooling unit according to a preset collection period; on the basis of the obtained temperature value of each single battery, when it is determined that the thermal management requirement is met, controlling a BMS management mode to be started; determining a target temperature parameter of the cell stack based on the obtained temperature value of each single cell; determining a target control strategy based on the target temperature parameter of the cell stack and a temperature threshold value corresponding to a preset control strategy; and if the current operation state of any liquid cooling unit meets the execution condition, controlling any liquid cooling unit to execute the target control strategy. And the BMS uniformly controls the liquid cooling unit corresponding to the whole battery stack to execute the target control strategy according to the battery temperature, so that the temperature rise between the battery clusters is consistent, the current between the clusters is consistent, and the performance of the whole energy storage power supply system is improved.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage systems, and in particular to a method, device and electronic equipment for thermal management of a liquid-cooled energy storage system. Background Art

[0002] As the core component of the energy storage system, energy storage batteries are essential for achieving efficient, stable and sustainable power supply, and temperature has a great impact on the battery capacity, power and safety of energy storage batteries. In large-scale energy storage system applications where multiple battery clusters are used in parallel, the system temperature difference control faces major challenges due to the large number of battery clusters (multiple battery packs connected in series) and battery packs (single battery pack).

[0003] Existing energy storage systems usually configure a liquid cooling unit for each battery stack. Each battery stack includes multiple battery clusters, and the temperature of the energy storage system is controlled by the liquid cooling unit based on the outlet water temperature. However, relying on the outlet water temperature as the control basis cannot accurately reflect the actual temperature inside each battery cluster, resulting in inconsistent battery temperature rise in each battery cluster, causing excessive temperature difference between battery clusters, resulting in a reduction in the life of the battery system, thereby causing the performance of the entire liquid-cooled energy storage system to decline. Summary of the invention

[0004] The embodiments of the present application provide a liquid-cooled energy storage system thermal management method, device and electronic equipment to ensure that the temperature between battery clusters in the liquid-cooled energy storage system is consistent, thereby improving the performance of the entire energy storage power supply system.

[0005] In a first aspect, an embodiment of the present application provides a thermal management method for a liquid-cooled energy storage system, wherein the liquid-cooled energy storage system includes at least one battery stack, at least one liquid cooling unit, and a battery management system BMS, wherein the battery stack corresponds to the liquid cooling unit one by one, and the method includes:

[0006] According to a preset collection cycle, the temperature value of each single cell in the battery stack corresponding to any one of the liquid cooling units is obtained;

[0007] When it is determined based on the acquired temperature values ​​of the individual batteries that the thermal management requirements are met, controlling the BMS management mode to be turned on;

[0008] Determining a target temperature parameter of the battery stack based on the acquired temperature value of each single battery;

[0009] Determining a target control strategy based on a target temperature parameter of the battery stack and a temperature threshold corresponding to a preset control strategy;

[0010] If the current operating state of any of the liquid cooling units meets the execution condition, any of the liquid cooling units is controlled to execute the target control strategy.

[0011] In some embodiments, determining the target temperature parameter of the battery stack based on the acquired temperature value of each single battery includes:

[0012] The maximum temperature of each single cell in the battery stack and the average temperature of all single cells are determined as target temperature parameters of the battery stack.

[0013] In some embodiments, the determining of the target control strategy based on the target temperature parameter of the battery stack and a temperature threshold value corresponding to a preset control strategy includes:

[0014] If the maximum temperature is not greater than the heating start-up temperature threshold and the average temperature is not greater than the first average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start heating;

[0015] If the maximum temperature is not less than the heating shut-off temperature threshold and the average temperature is not less than the second average temperature, determining that the target control strategy is to control the heating shut-off of the liquid cooling unit corresponding to the battery stack;

[0016] If the maximum temperature is not less than the cooling start-up temperature threshold and the average temperature is not less than the third average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start cooling;

[0017] If the maximum temperature is not greater than the cooling shutdown temperature threshold and the average temperature is not greater than the fourth average temperature, the target control strategy is determined to control the cooling shutdown of the liquid cooling unit corresponding to the battery stack.

[0018] In some embodiments, before determining the target control strategy based on the target temperature parameter of the battery stack and the temperature threshold value corresponding to the preset control strategy, the method further includes:

[0019] Obtaining the current value of each battery cluster in the battery stack;

[0020] Based on the acquired current values ​​of each battery cluster, determining whether the battery stack is in a charging or discharging state;

[0021] If the battery stack is in a charge and discharge state, the first temperature is determined as the refrigeration on temperature threshold, and the second temperature is determined as the refrigeration off temperature threshold;

[0022] If the battery stack is in a non-charging and discharging state, the third temperature is determined as the cooling-on temperature threshold, and the fourth temperature is determined as the cooling-off temperature threshold.

[0023] In some embodiments, judging whether the battery stack is in a charging or discharging state based on the acquired current value of each battery cluster includes:

[0024] Determining a battery cluster current average value based on the current values ​​of each battery cluster;

[0025] If the average current value of the battery cluster is greater than a preset current value, it is determined that the battery stack is in a charging and discharging state;

[0026] If the average current value of the battery cluster is not greater than the preset current value, it is determined that the battery stack is in a non-charging and discharging state.

[0027] In some embodiments, after controlling any of the liquid cooling units to execute the target control strategy, the method further includes:

[0028] If the target control strategy is cooling off or heating off, determining the average temperature of each battery cluster based on the temperature value of each single battery;

[0029] Based on the average temperature of each battery cluster, determining a cluster-level temperature difference, wherein the cluster-level temperature difference is used to characterize a maximum difference in average temperatures of each battery cluster in the battery stack;

[0030] If the cluster-level temperature difference is greater than a first temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to start self-circulation;

[0031] If the cluster-level temperature difference is not greater than a second temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to self-circulate and shut down;

[0032] If the cluster-level temperature difference is not greater than the third temperature difference threshold, the liquid cooling unit corresponding to the battery stack is controlled to enter a standby mode.

[0033] In a second aspect, an embodiment of the present application provides a thermal management device for a liquid-cooled energy storage system, wherein the liquid-cooled energy storage system includes at least one battery stack, at least one liquid cooling unit, and a battery management system BMS, wherein the battery stack corresponds to the liquid cooling unit one by one, and the device includes:

[0034] An acquisition module, used to acquire the temperature value of each single cell in the battery stack corresponding to any one of the liquid cooling units according to a preset acquisition cycle;

[0035] A first control module is used to control the BMS management mode to start when it is determined that the thermal management requirement is met based on the acquired temperature value of each single battery;

[0036] A first determination module, configured to determine a target temperature parameter of the battery stack based on the acquired temperature value of each single battery;

[0037] A second determination module, configured to determine a target control strategy based on a target temperature parameter of the battery stack and a temperature threshold value corresponding to a preset control strategy;

[0038] The second control module is used to control any of the liquid cooling units to execute the target control strategy if the current operating state of any of the liquid cooling units meets the execution condition.

[0039] In some embodiments, the first determining module is specifically configured to:

[0040] The maximum temperature of each single cell in the battery stack and the average temperature of all single cells are determined as target temperature parameters of the battery stack.

[0041] In some embodiments, the second determining module is specifically configured to:

[0042] If the maximum temperature is not greater than the heating start-up temperature threshold and the average temperature is not greater than the first average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start heating;

[0043] If the maximum temperature is not less than the heating shut-off temperature threshold and the average temperature is not less than the second average temperature, determining that the target control strategy is to control the heating shut-off of the liquid cooling unit corresponding to the battery stack;

[0044] If the maximum temperature is not less than the cooling start-up temperature threshold and the average temperature is not less than the third average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start cooling;

[0045] If the maximum temperature is not greater than the cooling shutdown temperature threshold and the average temperature is not greater than the fourth average temperature, the target control strategy is determined to control the cooling shutdown of the liquid cooling unit corresponding to the battery stack.

[0046] In some embodiments, the second determination module is further configured to:

[0047] Obtaining the current value of each battery cluster in the battery stack;

[0048] Based on the acquired current values ​​of each battery cluster, determining whether the battery stack is in a charging or discharging state;

[0049] If the battery stack is in a charge and discharge state, the first temperature is determined as the refrigeration on temperature threshold, and the second temperature is determined as the refrigeration off temperature threshold;

[0050] If the battery stack is in a non-charging and discharging state, the third temperature is determined as the cooling-on temperature threshold, and the fourth temperature is determined as the cooling-off temperature threshold.

[0051] In some embodiments, the second determining module is specifically configured to:

[0052] Determining a battery cluster current average value based on the current values ​​of each battery cluster;

[0053] If the average current value of the battery cluster is greater than a preset current value, it is determined that the battery stack is in a charging and discharging state;

[0054] If the average current value of the battery cluster is not greater than the preset current value, it is determined that the battery stack is in a non-charging and discharging state.

[0055] In some embodiments, after the second control module controls any one of the liquid cooling units to execute the target control strategy, it is further used to:

[0056] If the target control strategy is cooling off or heating off, determining the average temperature of each battery cluster based on the temperature value of each single battery;

[0057] Based on the average temperature of each battery cluster, determining a cluster-level temperature difference, wherein the cluster-level temperature difference is used to characterize a maximum difference in average temperatures of each battery cluster in the battery stack;

[0058] If the cluster-level temperature difference is greater than a first temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to start self-circulation;

[0059] If the cluster-level temperature difference is not greater than a second temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to self-circulate and shut down;

[0060] If the cluster-level temperature difference is not greater than the third temperature difference threshold, the liquid cooling unit corresponding to the battery stack is controlled to enter a standby mode.

[0061] In a third aspect, an embodiment of the present application provides an electronic device, comprising: at least one processor, and a memory communicatively connected to the at least one processor, wherein:

[0062] The memory stores a computer program that can be executed by at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the above-mentioned liquid-cooled energy storage system thermal management method.

[0063] In a fourth aspect, an embodiment of the present application provides a storage medium. When a computer program in the storage medium is executed by a processor of an electronic device, the electronic device can execute the above-mentioned thermal management method of the liquid-cooled energy storage system.

[0064] In a fifth aspect, an embodiment of the present application provides a computer program product, which, when called and executed by an electronic device, enables the electronic device to execute the above-mentioned liquid-cooled energy storage system thermal management method.

[0065] Compared with the prior art, the beneficial effects of the embodiments of the present application are at least as follows:

[0066] In the embodiment of the present application, the temperature value of each single cell in the battery stack corresponding to any liquid cooling unit is obtained according to the preset collection cycle; based on the obtained temperature value of each single cell, when it is determined that the thermal management requirements are met, the BMS management mode is controlled to be turned on; based on the obtained temperature value of each single cell, the target temperature parameter of the battery stack is determined; based on the target temperature parameter of the battery stack and the temperature threshold corresponding to the pre-set control strategy, the target control strategy is determined; if the current operating state of any liquid cooling unit meets the execution conditions, any liquid cooling unit is controlled to execute the target control strategy. In this way, the BMS uniformly controls the liquid cooling unit corresponding to the entire battery stack to execute the target control strategy according to the battery temperature, so that the temperature rise between battery clusters is consistent, the current between clusters is consistent, and the performance of the entire energy storage power system is improved.

[0067] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0069] Figure 1 A schematic diagram of the arrangement of a battery cluster and a liquid cooling unit in a battery compartment of a liquid-cooled energy storage system provided in an embodiment of the present application;

[0070] Figure 2 A flow chart of a thermal management method for a liquid-cooled energy storage system in the prior art provided in an embodiment of the present application;

[0071] Figure 3 A flow chart of a thermal management method for a liquid-cooled energy storage system provided in an embodiment of the present application;

[0072] Figure 4 A schematic diagram of the structure of a thermal management device for a liquid-cooled energy storage system provided in an embodiment of the present application;

[0073] Figure 5 A schematic diagram of the hardware structure of an electronic device for implementing a thermal management method for a liquid-cooled energy storage system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0074] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiment of the present application will be clearly and completely described below in conjunction with the drawings in the embodiment of the present application. Obviously, the described embodiment is only a part of the embodiment of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be arbitrarily combined with each other. In addition, although the logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in an order different from that here.

[0075] The terms "first" and "second" in the specification and claims of the present application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the term "comprising" and any of their variations are intended to cover non-exclusive protection. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. "Multiple" in the present application can mean at least two, for example, two, three or more, and the embodiments of the present application are not limited.

[0076] The following is a description of exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding, which should be considered as merely exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope of the present application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description. It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, which should be considered as exemplary, and their purpose is only to illustrate the feasibility of the implementation of the technical solution of the present application, but it does not mean that the applicant has or will necessarily use the solution.

[0077] In the technical solution of this application, the acquisition, transmission, storage, and use of data are in compliance with the requirements of relevant national laws and regulations.

[0078] The thermal management method for the liquid-cooled energy storage system proposed in this application is described below with reference to a specific embodiment.

[0079] See also Figure 1 , Figure 1A schematic diagram of the arrangement of a battery cluster and a liquid cooling unit in a battery compartment of a liquid-cooled energy storage system provided in an embodiment of the present application. The liquid-cooled energy storage system includes a battery system, a battery management system (Battery Management System, BMS) (not shown in the figure), dynamic environment equipment (water immersion sensor, temperature and humidity sensor, etc.) (not shown in the figure), a fire protection system, a liquid cooling unit, and other equipment such as a junction cabinet.

[0080] Among them, the battery system includes 12 battery clusters, namely battery cluster 1, battery cluster 2, battery cluster 3, battery cluster 4, battery cluster 5, battery cluster 6, battery cluster 7, battery cluster 8, battery cluster 9, battery cluster 10, battery cluster 11 and battery cluster 12, and each three clusters form a stack, that is, battery stack 1 includes battery cluster 1, battery cluster 2, and battery cluster 3, battery stack 2 includes battery cluster 4, battery cluster 5, and battery cluster 6, battery stack 3 includes battery cluster 7, battery cluster 8, and battery cluster 9, and battery stack 4 includes battery cluster 10, battery cluster 11, and battery cluster 12.

[0081] There are a total of 4 liquid cooling units, namely liquid cooling unit 1, liquid cooling unit 2, liquid cooling unit 3 and liquid cooling unit 4, which are deployed on both sides of the battery compartment respectively, wherein each liquid cooling unit corresponds to a battery stack, that is, liquid cooling unit 1 corresponds to battery stack 1, liquid cooling unit 2 corresponds to battery stack 2, liquid cooling unit 3 corresponds to battery stack 3, and liquid cooling unit 4 corresponds to battery stack 4. Each liquid cooling unit is mainly composed of a fan, a compressor, a water pump, a condenser, a heat exchanger, inlet and outlet water temperature sensors and other components. In an embodiment of the present application, the liquid cooling unit can execute a local control mode according to the outlet water temperature or execute a target control strategy according to the BMS instruction, that is, to perform cooling or heating to keep the battery temperature within a reasonable operating temperature range.

[0082] The fire protection system mainly includes composite gas detectors, temperature detectors, smoke detectors, sound and light alarm devices, gas release alarm devices, explosion-proof fans and shutters, heptafluoropropane or perfluorohexanone fire extinguishing devices, and water fire protection systems.

[0083] See also Figure 2 , Figure 2 A flow chart of a thermal management method for a liquid-cooled energy storage system in the prior art provided in an embodiment of the present application. The method can be executed by a liquid cooling unit, and the method includes the following steps.

[0084] In step 201, the outlet water temperature detected by the inlet and outlet water temperature sensors of the liquid cooling unit is obtained.

[0085] In step 202, a corresponding local control strategy is executed according to the outlet water temperature, wherein the local control strategy includes cooling on, heating on, cooling off, and heating off.

[0086] In specific implementation, a cooling on temperature threshold, a cooling off temperature threshold, a heating on temperature threshold, and a heating off temperature threshold are pre-set;

[0087] If the outlet water temperature is not less than the cooling start temperature threshold, the liquid cooling unit will start cooling;

[0088] If the outlet water temperature is not greater than the cooling shutdown temperature threshold, the liquid cooling unit will shut down the cooling;

[0089] If the outlet water temperature is not greater than the heating start temperature threshold, the liquid cooling unit will start heating;

[0090] If the outlet water temperature is not less than the heating shutdown temperature threshold, the liquid cooling unit will shut down heating;

[0091] In addition, when the outlet water temperature does not meet the above conditions, the liquid cooling unit enters the self-circulation mode to ensure the temperature difference of the battery cells.

[0092] However, relying solely on the liquid cooling unit to achieve temperature control of the energy storage system based on the outlet water temperature cannot accurately reflect the actual temperature inside each battery cluster, resulting in inconsistent battery temperature rise in each battery cluster, causing excessive temperature differences between battery clusters, shortening the life of the battery system, and thus causing the performance of the entire liquid-cooled energy storage system to decline.

[0093] In view of this, in order to solve the problem of excessive temperature difference between battery clusters in the liquid-cooled energy storage system in the prior art, the embodiments of the present application provide a liquid-cooled energy storage system thermal management method, device and electronic device. The following describes some preferred embodiments of the present application in conjunction with the drawings of the specification.

[0094] It should be noted that in each embodiment of the present application, the thermal management method of the liquid-cooled energy storage system is applied to Figure 1 The arrangement diagram of the battery cluster and the liquid cooling unit shown is used as an example for schematic illustration.

[0095] refer to Figure 3 , Figure 3 A flow chart of a thermal management method for a liquid-cooled energy storage system provided in an embodiment of the present application, wherein the liquid-cooled energy storage system comprises at least one battery stack, at least one liquid cooling unit and a battery management system BMS, wherein the battery stacks correspond one-to-one to the liquid cooling units, the method is executed by the BMS, and the method comprises the following steps.

[0096] In step 301, the temperature value of each single cell in the battery stack corresponding to any liquid cooling unit is obtained according to a preset collection cycle.

[0097] In specific implementation, the acquisition cycle refers to the time interval at which the BMS regularly reads the battery temperature. This cycle can be fixed (such as once a minute) or dynamically adjusted (based on the current working status or other factors). The BMS will measure the temperature of all single cells in the battery stack that is directly associated with the liquid cooling unit that issued the start request. Among them, the temperature sensor is usually installed near each single cell or integrated in the battery management system to accurately measure the temperature of each single cell. The measured temperature data is transmitted to the BMS through the internal communication network (such as CAN bus, RS485, etc.). Once the acquisition starts, the BMS will continue to repeat this process according to the preset acquisition cycle until certain stop conditions are met (such as reaching the expected temperature, receiving new instructions, etc.).

[0098] In step 302, based on the acquired temperature values ​​of the individual cells, when it is determined that the thermal management requirement is met, the BMS management mode is controlled to be turned on.

[0099] In specific implementation, the thermal management requirements can be met when the BMS detects that the battery stack temperature exceeds the safe range, or is automatically triggered according to a pre-programmed schedule. At this time, the BMS sends a mode instruction, and the liquid cooling unit will respond immediately after receiving the mode instruction, and perform temperature control and water temperature monitoring according to the predetermined process.

[0100] In step 303 , a target temperature parameter of the battery stack is determined based on the acquired temperature value of each single battery.

[0101] In a specific implementation, the maximum temperature of each single cell in the battery stack and the average temperature of all single cells can be determined as the target temperature parameters of the battery stack.

[0102] Assume that battery stack 1 has 48 cells, the highest temperature measured is 35°C, and the average temperature of all cells is 30°C. Then, these two values ​​(35°C and 30°C) will be used as target temperature parameters for subsequent control strategy decisions.

[0103] In step 304 , a target control strategy is determined based on the target temperature parameter of the battery stack and a temperature threshold value corresponding to a preset control strategy.

[0104] In specific implementation, the target temperature parameters of the battery stack are the maximum temperature of each single cell in the battery stack and the average temperature of all single cells. Then, it can be set that if the maximum temperature is not greater than the heating start-up temperature threshold and the average temperature is not greater than the first average temperature, the target control strategy is determined to control the heating of the liquid cooling unit corresponding to the battery stack to be turned on; if the maximum temperature is not less than the heating shutdown temperature threshold and the average temperature is not less than the second average temperature, the target control strategy is determined to control the heating of the liquid cooling unit corresponding to the battery stack to be turned off; if the maximum temperature is not less than the cooling start-up temperature threshold and the average temperature is not less than the third average temperature, the target control strategy is determined to control the cooling of the liquid cooling unit corresponding to the battery stack to be turned on; if the maximum temperature is not greater than the cooling shutdown temperature threshold and the average temperature is not greater than the fourth average temperature, the target control strategy is determined to control the cooling of the liquid cooling unit corresponding to the battery stack to be turned off.

[0105] Assume that the heating turn-on temperature threshold is 15°C, the first average temperature is 13°C, the heating turn-off temperature threshold is 25°C, the second average temperature is 22°C, the cooling turn-on temperature threshold is 40°C, the third average temperature is 35°C, the cooling turn-off temperature threshold is 30°C, and the fourth average temperature is 28°C. If the maximum temperature is not greater than the heating turn-on temperature threshold (such as 15°C) and the average temperature is not greater than the first average temperature (such as 13°C), start heating; if the maximum temperature is not less than the heating turn-off temperature threshold (such as 25°C) and the average temperature is not less than the second average temperature (such as 22°C), stop heating; if the maximum temperature is not less than the cooling turn-on temperature threshold (such as 40°C) and the average temperature is not less than the third average temperature (such as 35°C), start cooling; if the maximum temperature is not greater than the cooling turn-off temperature threshold (such as 30°C) and the average temperature is not greater than the fourth average temperature (such as 28°C), stop cooling.

[0106] In specific implementation, if the current maximum temperature is 41°C and the average temperature is 38°C, the system will start the cooling mode because these two values ​​exceed the cooling start temperature threshold (40°C) and the third average temperature (35°C). Once the maximum temperature drops to 30°C or below and the average temperature is below 28°C, the system will automatically stop cooling.

[0107] In a specific implementation, before determining the target control strategy based on the target temperature parameters of the battery stack and the temperature threshold corresponding to the pre-set control strategy, the current value of each battery cluster in the battery stack can also be obtained, and based on the obtained current value of each battery cluster, it is determined whether the battery stack is in a charging and discharging state. If the battery stack is in a charging and discharging state, the first temperature is determined as the refrigeration turn-on temperature threshold, and the second temperature is determined as the refrigeration turn-off temperature threshold. If the battery stack is in a non-charging and discharging state, the third temperature is determined as the refrigeration turn-on temperature threshold, and the fourth temperature is determined as the refrigeration turn-off temperature threshold.

[0108] For example, in the charging and discharging state: the refrigeration on temperature threshold is set to 38°C, and the refrigeration off temperature threshold is set to 30°C; in the non-charging and discharging state: the refrigeration on temperature threshold is set to 40°C. The refrigeration off temperature threshold is set to 35°C. In this way, if the battery stack is in the charging and discharging state, a set of lower refrigeration on temperature threshold and refrigeration off temperature threshold are used; if it is in the non-charging and discharging state, another set of higher refrigeration on temperature threshold and refrigeration off temperature threshold are used. During the charging and discharging process, a large number of chemical reactions occur inside the battery, resulting in the loss of energy conversion efficiency being released in the form of heat. The battery will heat up significantly during charging and discharging, and the current intensity during the charging and discharging process is large. Especially in the case of high-rate charging and discharging, the battery temperature changes more violently and frequently. Therefore, during the charging and discharging process, in order to cope with the risk of rapid temperature rise, a lower opening threshold is required to start the refrigeration function faster to ensure that the temperature does not quickly exceed the safe range. In the non-charging and discharging state, the temperature changes slowly, allowing the shutdown threshold to be slightly increased, and the thermal inertia of the battery and the surrounding environment to cool down naturally without having to stop cooling immediately. In the non-charging and discharging state, allowing a higher temperature threshold can reduce unnecessary cooling operations, thereby saving energy and reducing system operating costs.

[0109] In specific implementation, whether the battery stack is in a charging and discharging state can be judged in the following way: based on the current value of each battery cluster, the average current of the battery cluster is determined; if the average current of the battery cluster is greater than the preset current value, it is determined that the battery stack is in a charging and discharging state; if the average current of the battery cluster is not greater than the preset current value, it is determined that the battery stack is in a non-charging and discharging state.

[0110] In order to more accurately determine the working state of the battery stack, the system calculates the average current value of the battery cluster. If the average value is greater than the preset current value, the battery stack is considered to be in a charging or discharging state; otherwise, it is considered to be in a non-charging or discharging state.

[0111] Assume that there are three battery clusters in the battery stack, and their current values ​​are 4A, 6A, and 5A respectively. The calculated average current is 5A. If the preset charge and discharge current threshold is 2A, then 5A is obviously greater than this threshold, so it can be confirmed that the battery stack is in the charge and discharge state.

[0112] By monitoring the average current value of the battery cluster to determine the working status of the battery stack, not only the accuracy of temperature control is improved, but also improper operation caused by misjudgment can be effectively prevented.

[0113] In step 305, if the current operating state of any liquid cooling unit meets the execution condition, any liquid cooling unit is controlled to execute the target control strategy.

[0114] In specific implementation, the current operating state refers to the state of the liquid cooling unit before it performs any operation. This includes but is not limited to whether the liquid cooling unit has been started, its working mode (cooling or heating), the current temperature, and whether there are other operations in progress. Determining whether the current operating state of the liquid cooling unit meets the execution conditions is to ensure that the liquid cooling unit executes the control strategy in a safe and effective state.

[0115] For example, when the target control strategy is heating off, if the liquid cooling unit is in standby state at this time to execute heating on, there is no need to execute heating off, that is, the current operating state of the liquid cooling unit does not meet the execution conditions at this time, then maintain the current working state or enter standby mode, if the liquid cooling unit is in heating on at this time, then the current operating state of the liquid cooling unit meets the execution conditions at this time, then execute heating off, that is, once it is confirmed that the current operating state of the liquid cooling unit meets the execution conditions, the BMS will send a specific target control strategy to the liquid cooling unit, such as cooling on, cooling off, heating on or heating off.

[0116] During specific implementation, after controlling any liquid cooling unit to execute the target control strategy, if the target control strategy is cooling off or heating off, the average temperature of each battery cluster can also be determined based on the temperature value of each single battery; based on the average temperature of each battery cluster, the cluster-level temperature difference is determined, and the cluster-level temperature difference is used to characterize the maximum difference in the average temperatures of each battery cluster in the battery stack; if the cluster-level temperature difference is greater than the first temperature difference threshold, the liquid cooling unit corresponding to the battery stack is controlled to start self-circulation; if the cluster-level temperature difference is not greater than the second temperature difference threshold, the liquid cooling unit corresponding to the battery stack is controlled to stop self-circulation; if the cluster-level temperature difference is not greater than the third temperature difference threshold, the liquid cooling unit corresponding to the battery stack is controlled to enter standby mode.

[0117] In specific implementation, after executing the target control strategy, if the target control strategy is cooling off or heating off, the system further checks the average temperature of each battery cluster and the temperature difference between them (cluster-level temperature difference). According to the size of the cluster-level temperature difference, it decides whether to turn on or off the self-circulation function of the liquid cooling unit, or enter standby mode.

[0118] Assume that after the refrigeration is turned off, the system detects that the average temperature of each battery cluster is 27°C, 29°C and 32°C respectively. The cluster-level temperature difference (i.e., the maximum temperature difference) is 5°C. If the first temperature difference threshold is set to 4°C, the second temperature difference threshold is set to 3°C, and the third temperature difference threshold is set to 1°C, then because the cluster-level temperature difference is greater than the first temperature difference threshold, the BMS will control the liquid cooling unit to turn on the self-circulation to balance the temperature. If the cluster-level temperature difference further drops to less than the first temperature difference threshold but not greater than the second temperature difference threshold, the BMS will control the liquid cooling unit to turn off the self-circulation until the cluster-level temperature difference further drops to not greater than the third temperature difference threshold, and the BMS will control the liquid cooling unit to enter standby mode to save energy.

[0119] In this way, by introducing a self-circulation mechanism, the problem of local temperature difference that still exists even after cooling or heating stops is dealt with. This ensures that the temperature inside the battery stack is kept consistent even in low or high temperature environments, further protecting the health of the battery.

[0120] In specific implementation, according to the above control logic, there will not be a situation where cooling / heating are turned on at the same time or one operating mode meets the conditions of both turning on and off. However, in order to avoid accidents, the operating mode priority is specially formulated as follows:

[0121] (1) The BMS control liquid cooling unit operation priority > the liquid cooling unit local control mode operation priority;

[0122] (2) Refrigeration off priority > Refrigeration on priority;

[0123] (3) Heating off priority > heating on priority;

[0124] (4) Self-circulation priority > cooling start priority > heating start priority;

[0125] During specific implementation, the ambient temperature inside the battery compartment of the energy storage system collected by the temperature and humidity sensor can also be monitored; if the ambient temperature is lower than the preset low temperature alarm value, the liquid cooling unit corresponding to each battery stack is controlled to stop cooling; if the ambient temperature is higher than the preset high temperature alarm value, the liquid cooling unit corresponding to each battery stack is controlled to stop heating.

[0126] In specific implementation, when the BMS detects a failure in the energy storage power system, a fire alarm, or a water immersion sensor alarm, the BMS can issue a shutdown command to the liquid cooling unit; when the BMS detects a communication failure with the liquid cooling unit, the BMS can also control the shutdown of the entire liquid-cooled energy storage system and sound an alarm.

[0127] In the embodiment of the present application, the liquid-cooled energy storage system can perform a local control mode, that is, operate in a corresponding mode according to the water outlet temperature of the unit, and can also execute a BMS management mode, in which the BMS controls the liquid cooling unit to operate in a corresponding mode according to the battery cell temperature to keep the temperature between battery clusters in the cabin from being too high. In addition, the unit itself operates at a variable frequency to reduce the power consumption of the liquid cooling unit, and uniformly controls the liquid cooling unit corresponding to the entire battery stack to execute a target control strategy, so that the temperature rise between battery clusters is consistent, and the current between clusters is consistent, thereby improving the performance of the entire energy storage power supply system. When the cooling / heating is turned off, if the temperature difference of the battery cells in the cluster is too high, the BMS can also control the liquid cooling unit to perform a self-circulation mode to reduce the temperature difference between the battery cells and ensure the battery discharge capacity. By setting the priority of the liquid cooling unit operation mode and the thermal management strategy under the fault or alarm state of the energy storage power supply system, the battery temperature is avoided from being out of control, and the safe and efficient operation of the energy storage power supply system is guaranteed.

[0128] Based on the same inventive concept, the embodiment of the present application also provides a liquid-cooled energy storage system thermal management device. The principle of solving the problem by the liquid-cooled energy storage system thermal management device is similar to the above-mentioned liquid-cooled energy storage system thermal management method. Therefore, the implementation of the liquid-cooled energy storage system thermal management device can refer to the implementation of the liquid-cooled energy storage system thermal management method, and the repeated parts will not be repeated.

[0129] Figure 4 A schematic diagram of the structure of a thermal management device for a liquid-cooled energy storage system provided in an embodiment of the present application, wherein the liquid-cooled energy storage system includes at least one battery stack, at least one liquid cooling unit, and a battery management system BMS, wherein the battery stack corresponds to the liquid cooling unit one by one, and the device includes:

[0130] The acquisition module 401 is used to acquire the temperature value of each single cell in the battery stack corresponding to any liquid cooling unit according to a preset acquisition cycle;

[0131] The first control module 402 is used to control the BMS management mode to start when it is determined that the thermal management requirement is met based on the acquired temperature value of each single battery;

[0132] A first determination module 403, configured to determine a target temperature parameter of the battery stack based on the acquired temperature value of each single battery;

[0133] A second determination module 404 is used to determine a target control strategy based on a target temperature parameter of the battery stack and a temperature threshold corresponding to a preset control strategy;

[0134] The second control module 405 is configured to control any of the liquid cooling units to execute the target control strategy if the current operating state of any of the liquid cooling units meets the execution condition.

[0135] In some embodiments, the first determining module 403 is specifically configured to:

[0136] The maximum temperature of each single cell in the battery stack and the average temperature of all single cells are determined as target temperature parameters of the battery stack.

[0137] In some embodiments, the second determining module 404 is specifically configured to:

[0138] If the maximum temperature is not greater than the heating start-up temperature threshold and the average temperature is not greater than the first average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start heating;

[0139] If the maximum temperature is not less than the heating shut-off temperature threshold and the average temperature is not less than the second average temperature, determining that the target control strategy is to control the heating shut-off of the liquid cooling unit corresponding to the battery stack;

[0140] If the maximum temperature is not less than the cooling start-up temperature threshold and the average temperature is not less than the third average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start cooling;

[0141] If the maximum temperature is not greater than the cooling shutdown temperature threshold and the average temperature is not greater than the fourth average temperature, the target control strategy is determined to control the cooling shutdown of the liquid cooling unit corresponding to the battery stack.

[0142] In some embodiments, the second determination module 404 is further configured to:

[0143] Obtaining the current value of each battery cluster in the battery stack;

[0144] Based on the acquired current values ​​of each battery cluster, determining whether the battery stack is in a charging or discharging state;

[0145] If the battery stack is in a charge and discharge state, the first temperature is determined as the refrigeration on temperature threshold, and the second temperature is determined as the refrigeration off temperature threshold;

[0146] If the battery stack is in a non-charging and discharging state, the third temperature is determined as the cooling-on temperature threshold, and the fourth temperature is determined as the cooling-off temperature threshold.

[0147] In some embodiments, the second determining module 404 is specifically configured to:

[0148] Determining a battery cluster current average value based on the current values ​​of each battery cluster;

[0149] If the average current value of the battery cluster is greater than a preset current value, it is determined that the battery stack is in a charging and discharging state;

[0150] If the average current value of the battery cluster is not greater than the preset current value, it is determined that the battery stack is in a non-charging and discharging state.

[0151] In some embodiments, after the second control module 405 controls any of the liquid cooling units to execute the target control strategy, it is further used to:

[0152] If the target control strategy is cooling off or heating off, determining the average temperature of each battery cluster based on the temperature value of each single battery;

[0153] Based on the average temperature of each battery cluster, determining a cluster-level temperature difference, wherein the cluster-level temperature difference is used to characterize a maximum difference in average temperatures of each battery cluster in the battery stack;

[0154] If the cluster-level temperature difference is greater than a first temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to start self-circulation;

[0155] If the cluster-level temperature difference is not greater than a second temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to self-circulate and shut down;

[0156] If the cluster-level temperature difference is not greater than the third temperature difference threshold, the liquid cooling unit corresponding to the battery stack is controlled to enter a standby mode.

[0157] The division of modules in the embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, the functional modules in the embodiments of the present application may be integrated in a processor, or may exist physically separately, or two or more modules may be integrated in one module. The coupling between the modules may be achieved through some interfaces, which are usually electrical communication interfaces, but it is not excluded that they may be mechanical interfaces or other forms of interfaces. Therefore, the modules described as separate components may or may not be physically separated, and may be located in one place or distributed to different locations of the same or different devices. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0158] After introducing the energy storage system thermal management method and device according to the exemplary embodiment of the present application, next, an electronic device according to another exemplary embodiment of the present application is introduced.

[0159] Based on the same inventive concept, the embodiment of the present application provides an electronic device, which can realize the function of the thermal management device of the liquid-cooled energy storage system discussed above, please refer to Figure 5 , the device includes a memory 501 , one or more processors 502 , and a bus 503 .

[0160] The memory 501 is used for executing computer programs in the memory 501. The memory 501 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system and programs required for running the instant messaging function, etc.; the data storage area may store various instant messaging information and operation instruction sets, etc.

[0161] The memory 501 may be a volatile memory, such as a random-access memory (RAM); the memory 501 may also be a non-volatile memory, such as a read-only memory, a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), or the memory 501 may be any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 501 may be a combination of the above memories.

[0162] The processor 502 may include one or more central processing units (CPU) or a digital processing unit, etc. The processor 502 is used to implement the thermal management method of the liquid-cooled energy storage system in the above embodiment when calling the computer program stored in the memory 501 .

[0163] The specific connection medium between the memory 501 and the processor 502 is not limited in the embodiment of the present application. Figure 5 In the embodiment, the memory 501 and the processor 502 are connected via a bus 503. The bus 503 is connected to the processor 502 via a bus 503. Figure 5 The connections between other components are shown in bold lines, which are only for illustration and are not intended to be limiting. Bus 503 can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 5 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0164] Based on the same inventive concept, the embodiment of the present application provides a computer-readable storage medium, and the computer program product includes: computer program code, when the computer program code is run on a computer, the computer executes the liquid-cooled energy storage system thermal management method as discussed above. Since the principle of solving the problem by the above-mentioned computer-readable storage medium is similar to that of the liquid-cooled energy storage system thermal management method, the implementation of the above-mentioned computer-readable storage medium can refer to the implementation of the method, and the repeated parts will not be repeated.

[0165] Based on the same inventive concept, the embodiment of the present application also provides a computer program product, which includes: computer program code, when the computer program code is run on a computer, the computer executes the liquid-cooled energy storage system thermal management method as discussed above. Since the principle of solving the problem by the above computer program product is similar to that of the liquid-cooled energy storage system thermal management method, the implementation of the above computer program product can refer to the implementation of the method, and the repeated parts will not be repeated.

[0166] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0167] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0168] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0169] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of user-operated steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0170] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A thermal management method for a liquid-cooled energy storage system, characterized in that: The liquid-cooled energy storage system includes at least one battery stack, at least one liquid cooling unit and a battery management system BMS, wherein the battery stacks correspond to the liquid cooling units one by one, and the method includes: According to a preset collection cycle, the temperature value of each single cell in the battery stack corresponding to any one of the liquid cooling units is obtained; When it is determined based on the acquired temperature values ​​of the individual batteries that the thermal management requirements are met, controlling the BMS management mode to be turned on; Determining a target temperature parameter of the battery stack based on the acquired temperature value of each single battery; Determining a target control strategy based on a target temperature parameter of the battery stack and a temperature threshold corresponding to a preset control strategy; If the current operating state of any of the liquid cooling units meets the execution condition, any of the liquid cooling units is controlled to execute the target control strategy.

2. The method according to claim 1, characterized in that The step of determining a target temperature parameter of the battery stack based on the acquired temperature value of each single battery cell includes: The maximum temperature of each single cell in the battery stack and the average temperature of all single cells are determined as target temperature parameters of the battery stack.

3. The method according to claim 2, characterized in that The determining of the target control strategy based on the target temperature parameter of the battery stack and the temperature threshold value corresponding to the preset control strategy includes: If the maximum temperature is not greater than the heating start-up temperature threshold and the average temperature is not greater than the first average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start heating; If the maximum temperature is not less than the heating shut-off temperature threshold and the average temperature is not less than the second average temperature, determining that the target control strategy is to control the heating shut-off of the liquid cooling unit corresponding to the battery stack; If the maximum temperature is not less than the cooling start-up temperature threshold and the average temperature is not less than the third average temperature, determining that the target control strategy is to control the liquid cooling unit corresponding to the battery stack to start cooling; If the maximum temperature is not greater than the cooling shutdown temperature threshold and the average temperature is not greater than the fourth average temperature, the target control strategy is determined to control the cooling shutdown of the liquid cooling unit corresponding to the battery stack.

4. The method according to claim 3, characterized in that Before determining the target control strategy based on the target temperature parameter of the battery stack and the temperature threshold value corresponding to the preset control strategy, the method further includes: Obtaining the current value of each battery cluster in the battery stack; Based on the acquired current values ​​of each battery cluster, determining whether the battery stack is in a charging or discharging state; If the battery stack is in a charge and discharge state, the first temperature is determined as the refrigeration on temperature threshold, and the second temperature is determined as the refrigeration off temperature threshold; If the battery stack is in a non-charging and discharging state, the third temperature is determined as the cooling-on temperature threshold, and the fourth temperature is determined as the cooling-off temperature threshold.

5. The method according to claim 4, characterized in that The determining whether the battery stack is in a charge or discharge state based on the acquired current value of each battery cluster includes: Determining a battery cluster current average value based on the current values ​​of each battery cluster; If the average current value of the battery cluster is greater than a preset current value, it is determined that the battery stack is in a charging and discharging state; If the average current value of the battery cluster is not greater than the preset current value, it is determined that the battery stack is in a non-charging and discharging state.

6. The method according to any one of claims 1 to 5, characterized in that: After controlling any of the liquid cooling units to execute the target control strategy, the method further includes: If the target control strategy is cooling off or heating off, determining the average temperature of each battery cluster based on the temperature value of each single battery; Based on the average temperature of each battery cluster, determining a cluster-level temperature difference, wherein the cluster-level temperature difference is used to characterize a maximum difference in average temperatures of each battery cluster in the battery stack; If the cluster-level temperature difference is greater than a first temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to start self-circulation; If the cluster-level temperature difference is not greater than a second temperature difference threshold, controlling the liquid cooling unit corresponding to the battery stack to self-circulate and shut down; If the cluster-level temperature difference is not greater than the third temperature difference threshold, the liquid cooling unit corresponding to the battery stack is controlled to enter a standby mode.

7. A thermal management device for a liquid-cooled energy storage system, characterized in that: The liquid-cooled energy storage system includes at least one battery stack, at least one liquid cooling unit and a battery management system BMS, wherein the battery stack corresponds to the liquid cooling unit one by one, and the device includes: An acquisition module, used to acquire the temperature value of each single cell in the battery stack corresponding to any one of the liquid cooling units according to a preset acquisition cycle; A first control module is used to control the BMS management mode to start when it is determined that the thermal management requirement is met based on the acquired temperature value of each single battery; A first determination module, configured to determine a target temperature parameter of the battery stack based on the acquired temperature value of each single battery; A second determination module, configured to determine a target control strategy based on a target temperature parameter of the battery stack and a temperature threshold value corresponding to a preset control strategy; The second control module is used to control any of the liquid cooling units to execute the target control strategy if the current operating state of any of the liquid cooling units meets the execution condition.

8. The device according to claim 7, characterized in that The first determining module is specifically configured to: The maximum temperature of each single cell in the battery stack and the average temperature of all single cells are determined as target temperature parameters of the battery stack.

9. An electronic device, characterized in that: include: at least one processor, and a memory communicatively connected to the at least one processor, wherein: The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the method according to any one of claims 1 to 6.

10. A storage medium, characterized in that: When the computer program in the storage medium is executed by a processor of an electronic device, the electronic device can execute the method according to any one of claims 1 to 6.

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