Cooling method of energy storage system, energy storage system and energy storage equipment

Abstract

The invention relates to the field of energy storage, in particular to a cooling method of an energy storage system, the energy storage system and energy storage equipment. The cooling method of the energy storage system comprises the following steps: acquiring temperature information of each battery cluster through acquisition equipment, and determining a first battery cluster needing to be cooled according to the temperature information; when at least two first battery clusters are included, the cooling priority of each first battery cluster is calculated, and the first battery cluster with the highest cooling priority is determined as a target battery cluster; conducting a second valve for connecting the target battery cluster with a second liquid cooling unit, and cooling the target battery cluster through the second liquid cooling unit; wherein the first valves, connected with the first liquid cooling unit, of the first battery clusters are always switched on, and the first battery clusters are cooled through the first liquid cooling unit. According to the embodiment of the invention, the two groups of liquid cooling units are arranged to adjust the temperature of the battery clusters, so that efficient single-cluster adjustment can be realized while the temperature of each battery cluster is not greatly changed.

Description

Technical Field

[0001] The present application relates to the field of energy storage, and in particular to a cooling method for an energy storage system, an energy storage system, and an energy storage device. Background Art

[0002] Existing energy storage systems consist of multiple battery packs. These are connected in series or parallel with a power conversion system (PCS) and other ancillary equipment to form an independently operating assembly called a battery cluster. Each battery cluster is connected to a liquid cooling system via a valve, enabling thermal management of the individual battery clusters.

[0003] The energy storage system is also equipped with a liquid cooling unit, which is connected to the liquid cooling pipeline. It cools the coolant through a refrigeration cycle and conducts the coolant into the liquid cooling pipeline to cool the battery cluster.

[0004] When cooling individual battery clusters, the flow rate to different battery clusters can be adjusted by adjusting the opening of the valves on the liquid cooling lines connected to the corresponding battery clusters, thereby keeping the temperature at a roughly uniform level. However, this approach will inevitably cause changes in the flow rate to other battery clusters, resulting in temperature increases and other problems. Summary of the Invention

[0005] Embodiments of the present invention provide a cooling method, an energy storage system, and an energy storage device for an energy storage system, to solve the problem of other cluster temperature changes that may occur when cooling a battery cluster by a liquid cooling unit in the prior art.

[0006] In a first aspect, an embodiment of the present invention provides a cooling method for an energy storage system, wherein the energy storage system includes multiple battery clusters, each of which is connected to a first liquid cooling unit and a second liquid cooling unit via a valve. The cooling method for the energy storage system includes: Acquiring temperature information of each battery cluster through a collection device, and determining a first battery cluster that needs to be cooled based on the temperature information; When at least two first battery clusters are included, respectively calculating the cooling priority of each of the first battery clusters, and determining the first battery cluster with the highest cooling priority as the target battery cluster; opening the second valve connecting the target battery cluster and the second liquid cooling unit, and closing the second valves of other battery clusters, so as to cool the target battery cluster through the second liquid cooling unit; The first valve connecting each of the first battery clusters and the first liquid cooling unit is always open, so that each of the first battery clusters is cooled by the first liquid cooling unit.

[0007] In a second aspect, an embodiment of the present invention provides an energy storage system, comprising a plurality of battery clusters, each of which is connected to a first liquid cooling unit and a second liquid cooling unit via a valve. The system comprises: a first determining module, which acquires temperature information of each battery cluster through a collection device and determines a first battery cluster that needs to be cooled based on the temperature information; a second determining module, when at least two first battery clusters are included, calculating the cooling priority of each of the first battery clusters respectively, and determining the first battery cluster with the highest cooling priority as the target battery cluster; a cooling module, which opens the second valve connecting the target battery cluster and the second liquid cooling unit, and closes the second valves of other battery clusters, so as to cool the target battery cluster through the second liquid cooling unit; The first valve connecting each battery cluster to the first liquid cooling unit is always open, and each battery cluster is cooled by the first liquid cooling unit.

[0008] In a third aspect, an embodiment of the present invention provides an energy storage device, comprising the energy storage system described in any one of the second aspects, and configured to execute the cooling method for the energy storage system described in any one of the first aspects.

[0009] In an embodiment of the present invention, an additional set of liquid cooling units is added to the existing set of liquid cooling units in the energy storage system, allowing the battery clusters to be cooled simultaneously by two sets of liquid cooling units. The first liquid cooling unit simultaneously cools each first battery cluster that requires cooling, and is always open without controlling valve state changes. This avoids temperature changes in each battery cluster caused by changes in coolant flow when cooling different battery clusters using a single cooling unit, ensuring that the temperature of each battery cluster remains at the same level without significant fluctuations. Simultaneously, the highest-priority target battery cluster is determined based on the acquired temperature information, and the second liquid cooling unit independently adjusts the temperature of the target battery cluster to quickly adjust the temperature of the target battery cluster to a normal level, thus achieving single-cluster management of the target battery cluster temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0011] Figure 1 FIG2 is a schematic structural diagram of an energy storage system provided in an embodiment of the present application; Figure 2Shown is a flow chart of a cooling method for an energy storage system provided by an embodiment of the present invention; Figure 3 FIG2 is a schematic structural diagram of another energy storage system provided in an embodiment of the present application; Figure 4 Shown is a structural schematic diagram of an energy storage device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0012] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0013] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0014] like Figure 1 Figure 1 is a schematic diagram of the structure of an energy storage system provided by an embodiment of the present invention. The energy storage system provided by an embodiment of the present invention includes a first liquid cooling unit, a second liquid cooling unit, and several battery clusters. Each battery cluster is connected to the first and second liquid cooling units via valves.

[0015] The specific connection relationship between the battery cluster and the first liquid cooling unit and the second liquid cooling unit is as follows: Figure 1 As shown. Since the connection relationship between each battery cluster and the first liquid cooling unit and the second liquid cooling unit is the same, and the number of battery clusters in the energy storage system is not limited, Figure 1 Only one set of battery clusters is shown to illustrate the connection relationship.

[0016] See also Figure 1 The battery cluster includes two water inlets and one water outlet. These inlets connect the battery cluster to two independent water inlet pipes and one water outlet pipe. These two water inlet pipes are connected to the first and second liquid cooling units, respectively, to circulate coolant from the cooling units to cool the battery cluster.

[0017] Valves installed on the water inlet pipes control the flow of water, thereby enabling the liquid cooling unit to control the cooling of the battery cluster by opening and closing the valves. A first valve is installed on the pipe connecting to the first liquid cooling unit, and a second valve is installed on the pipe connecting to the second liquid cooling unit. Typically, the first valve is a solenoid valve, and the second valve is a ball valve.

[0018] The energy storage system also includes a battery management system (BMS). The battery cluster of the energy storage system also includes data collection equipment.

[0019] The acquisition equipment is deployed in the battery cluster to collect the temperature information of the battery cluster.

[0020] The BMS is connected to the data acquisition device in each battery cluster and the first valve and second valve of each battery cluster respectively, and is used to determine whether the battery cluster needs to be cooled according to the temperature information of each battery cluster, and thus cool the battery cluster by controlling the opening and closing of the first valve and the second valve. Figure 1 Shown in.

[0021] In this embodiment of the present invention, the energy storage system is equipped with two liquid cooling units, each connected to the battery cluster via a water inlet pipe and valve to achieve cooling of the battery cluster. The valves connecting the two liquid cooling units to the battery clusters are controlled by the energy storage system's BMS to distribute the coolant to each battery cluster.

[0022] Among them, a group of liquid cooling units is used to cool the battery cluster with the highest priority among all the battery clusters that need to be cooled, so as to quickly adjust its temperature to normal temperature and avoid battery cluster failure.

[0023] The other set of liquid cooling units is used to keep all battery clusters that need temperature regulation turned on at all times, so that the coolant flows through all battery clusters that need cooling. This avoids temperature fluctuations caused by changes in the coolant flow through other battery clusters when the first set of liquid cooling units is used alone to circulate coolant through a certain battery cluster, ensuring that the temperatures of all battery clusters remain at the same level.

[0024] like Figure 2 As shown in FIG, a cooling method for an energy storage system provided by an embodiment of the present invention is applied to Figure 1 The energy storage system shown is shown in Figure 2 , the specific steps of the method include: S201 : Acquire temperature information of each battery cluster through a collection device, and determine a first battery cluster that needs to be cooled based on the temperature information.

[0025] Specifically, the acquisition equipment is deployed above the battery cell tabs in each battery cluster to collect the temperature of each battery cell in the cluster. When deploying the acquisition equipment, it is necessary to ensure that the temperature sensors are deployed evenly and regularly so as to accurately reflect the temperature distribution of all battery cells in the battery pack. The temperature information obtained is the overall temperature of the battery cluster determined based on the battery cell temperatures collected by each acquisition device in the cluster. The temperature information can be the highest temperature in the battery cluster, or the average temperature in the battery cluster, or other achievable temperature forms. The embodiment of the present invention is described using the highest temperature as an example.

[0026] Generally, the acquisition device is usually implemented as a temperature sensor.

[0027] The average temperature of the energy storage system is determined based on the maximum temperature of each battery cluster. Furthermore, the maximum temperature difference of each battery cluster is determined based on the difference between the maximum temperature of each battery cluster and the average temperature of the energy storage system. The maximum temperature difference of each battery cluster reflects the difference between the battery cluster temperature and the normal system temperature, and is used to determine whether the battery cluster needs cooling.

[0028] In a specific implementation, the maximum temperature difference is calculated as follows: ; in, is the maximum temperature, is the average temperature, is the maximum temperature difference.

[0029] By comparing the maximum temperature difference of each battery cluster with a preset cooling temperature threshold, the battery cluster with a maximum temperature difference greater than the cooling temperature threshold is determined as the first battery cluster to be cooled. The battery cluster with a maximum temperature difference less than the cooling temperature threshold does not need to be cooled.

[0030] S202 : When at least two first battery clusters are included, respectively calculate the cooling priority of each first battery cluster, and determine the first battery cluster with the highest cooling priority as the target battery cluster.

[0031] Specifically, when there are multiple first battery clusters that need to be cooled at the same time, a target battery cluster is determined according to the cooling priority.

[0032] In this embodiment of the present invention, the cooling priority of each first battery cluster can be quantitatively calculated. The cooling priority of a battery cluster is determined by the cumulative value of abnormal temperatures within a battery cluster over a period of time, the rate of change of abnormal temperatures over that period of time, and the amount of temperature abnormality exceeding the standard temperature. These priorities are quantitatively calculated using the first priority contribution value, the second priority contribution value, and the third priority contribution value.

[0033] According to different actual scenarios, the importance of the three parts of the cooling priority is different. Different weight coefficients are set and assigned to the first priority contribution value, the second priority contribution value and the third priority contribution value to comprehensively determine the cooling priority of the battery cluster in the corresponding scenario.

[0034] During the quantitative calculation, a first priority contribution value based on the accumulated temperature deviation value, a second priority contribution value based on the maximum temperature change rate, and a third priority contribution value based on the temperature deviation value are determined for each first battery. Based on the first, second, and third priority contribution values ​​of each battery cluster, the cooling priority of each battery cluster is determined.

[0035] Among them, the first priority contribution value is determined by the maximum temperature difference of each first battery cluster, the time when the maximum temperature of each first battery cluster exceeds the average temperature, and the corresponding first coefficient; the second priority contribution value is determined by the maximum temperature difference of each first battery cluster at a time interval and the average temperature difference of the energy storage system, and the corresponding second coefficient; the third priority contribution value is determined by the maximum temperature difference of each first battery cluster and the corresponding third coefficient.

[0036] In a specific implementation, the cooling priority is calculated as follows: ; in, 、 、 are the first coefficient, the second coefficient and the third coefficient respectively, is the maximum temperature corresponding to the first battery cluster, is the average temperature, is the time corresponding to the first battery cluster exceeding the average temperature, is the time variation over a period of time, is the maximum temperature change between two adjacent moments, is the average temperature change over a period of time.

[0037] The first part of the above formula is used to represent the cumulative value of the abnormal temperature of the battery cluster within time T, the second part is used to represent the rate of change of the abnormal temperature of the battery cluster during the period from T-1 to T, and the third part is used to represent the extent to which the battery cluster temperature exceeds the standard temperature.

[0038] In an embodiment of the present invention, 、 、 The value of is determined by the actual operating conditions of the system and the parameters of each component of the energy storage system.

[0039] For example, if the energy storage system needs to be charged and discharged continuously for a long time, the accumulated deviation value is relatively large during long-term operation, so it is necessary to reduce The value of , through the smaller first coefficient to maintain the robustness of the expression; if in high rate, short time charge and discharge conditions, due to the high temperature rise rate of the system, it is necessary to reduce The value of is chosen to maintain the robustness of the expression through a smaller third coefficient.

[0040] S203, opening the second valve connecting the target battery cluster to the second liquid cooling unit, and closing the second valves of other battery clusters, and cooling the target battery cluster by the second liquid cooling unit; wherein, the first valve connecting each first battery cluster to the first liquid cooling unit is always opened, and each first battery cluster is cooled by the first liquid cooling unit.

[0041] Specifically, after multiple battery clusters are identified as a first battery cluster, the first valves of all first battery clusters are opened, and the first liquid cooling unit cools all first battery clusters to ensure that the temperature of each first battery cluster does not fluctuate significantly. Simultaneously, the second valve of the target battery cluster is opened, and the target battery cluster is cooled by the second liquid cooling unit to quickly cool the target battery cluster to a normal level.

[0042] Among them, since the first valve will always be on and does not need to be adjusted multiple times, a ball valve can be set as the first valve; and since the second valve will be turned on and off multiple times, a solenoid valve can be set as the second valve.

[0043] In this embodiment of the present invention, the first liquid cooling unit simultaneously cools the first battery cluster that requires cooling, maintaining a constant open state without changing the valve status. This prevents temperature fluctuations in the battery clusters caused by changes in coolant flow when cooling different battery clusters. Simultaneously, the second battery cluster regulates the temperature of the target battery cluster, achieving single-cluster temperature management of the target battery cluster.

[0044] Furthermore, the target battery cluster's temperature information is used to determine whether the target battery cluster has achieved a cooling effect. If the target battery cluster is determined to have achieved a cooling effect, the second valve connecting the target battery cluster to the second liquid cooling unit is closed, stopping cooling of the target battery cluster by the second liquid cooling unit. The first battery cluster with the next highest priority is then re-identified as the target battery cluster, and its second valve connecting to the second liquid cooling unit is opened to cool the target battery cluster. If the target battery cluster is determined not to have achieved a cooling effect, the second valve connecting the target battery cluster to the second liquid cooling unit is continuously opened to cool the second battery cluster.

[0045] In this embodiment of the present invention, after the valve of the target battery cluster is opened, temperature information is promptly used to determine whether cooling has been completed. When cooling is complete, the second valve is promptly closed and cooling is continued for other battery clusters, thereby achieving energy conservation and improving cooling efficiency.

[0046] When determining whether the target battery cluster has achieved the cooling effect, the maximum temperature difference of the target battery cluster is compared with a preset cooling temperature threshold. When the maximum temperature difference is lower than the cooling temperature threshold, it is determined that the target battery cluster has achieved the cooling effect.

[0047] Optionally, when determining whether the target battery cluster has achieved the cooling effect, a minimum operating time may be calculated based on the temperature information, and the time the target battery cluster is cooled by opening the second valve may be measured. When the actual cooling time of the target battery cluster by the second liquid cooling unit reaches the minimum operating time, the target battery cluster is determined to have achieved the cooling effect.

[0048] The shortest operating time is the time it takes for the target battery cluster to be cooled by the second liquid cooling unit to ensure that the target battery cluster can achieve a cooling effect.

[0049] In this embodiment, by estimating the time required to complete cooling of the target battery cluster and determining that cooling is completed at the corresponding time, and closing the second valve, it is possible to avoid the situation where the valve is not closed due to failure to recognize that cooling is complete when cooling is actually completed due to various faults, thereby avoiding the need to cool the same battery cluster all the time under fault conditions, thereby achieving the effect of saving energy and improving cooling efficiency.

[0050] When calculating the shortest operating time based on the temperature information, the temperature difference to be adjusted is determined based on the maximum temperature difference of the target battery cluster and the cooling temperature threshold. Generally, the temperature difference to be adjusted is the difference between the maximum temperature difference of the target battery cluster and the cooling temperature threshold.

[0051] The first amount of heat required to achieve cooling for the target battery cluster is determined based on the temperature difference to be adjusted, the total mass of the target battery cluster, and the specific heat capacity of the battery cluster. The second amount of heat required to achieve cooling for the target battery cluster is determined based on the specific heat capacity of the coolant in the second liquid cooling unit, the mass flow rate of the coolant per cluster, the temperature difference between the inlet and outlet water of the coolant per cluster, and the heat generation rate of the target battery cluster. The minimum operating time is determined based on the first and second amounts of heat.

[0052] The specific heat capacity of the battery cluster is determined by the average specific heat capacity of the battery cells, and the total mass of the target battery cluster is determined by the mass of each battery cell in the target battery cluster.

[0053] In a specific implementation, the shortest running time is calculated as follows: ; in, is the specific heat capacity of the battery cluster, is the total mass of the target battery cluster, is the temperature difference to be adjusted, used to determine the first heat amount; is the specific heat capacity of the coolant in the second liquid cooling unit, is the coolant mass flow rate of a single cluster, The temperature difference between the inlet and outlet of a single cluster coolant is: is the heat generation rate of the target battery cluster, used to determine the second heat amount; is the shortest running time, which is obtained by calculating the ratio of the first heat to the second heat.

[0054] In the above formula, The amount of heat that the target battery cluster needs to release to reduce the temperature of the target battery cluster to a normal level, i.e., the first amount of heat; The amount of heat required for the coolant in the second liquid cooling unit to reduce the target battery cluster's temperature to a normal level is called the second heat. The time required to reduce the target battery cluster's temperature to a normal level is determined by calculating the ratio of the first heat to the second heat.

[0055] Optionally, in some embodiments, the number of times each battery cluster requires cooling is counted, that is, the number of times the maximum temperature difference of each battery cluster exceeds a cooling temperature threshold is counted. When the number of times any battery cluster requires cooling reaches a preset threshold, the second valve of the target battery cluster is continuously opened and an alarm is reported. This allows the long-term temperature status of the battery cluster to be determined based on whether it needs to be adjusted as soon as possible.

[0056] Optionally, in some embodiments, when determining the temperature difference to be adjusted, in addition to determining it based on the maximum temperature difference and the cooling temperature threshold of the target battery cluster, a temperature difference adjustment redundancy value can also be introduced to correct and adjust the temperature difference to be adjusted determined based on the maximum temperature difference and the cooling temperature threshold through the temperature difference adjustment redundancy value, so as to change the adjustment method of the battery cluster according to the actual scenario and the actual situation of the battery cluster, thereby improving the accuracy of the temperature adjustment of the battery cluster and improving the adjustment efficiency.

[0057] When the number of cooling operations required does not reach a preset threshold, as the number of cooling operations for the same battery cluster as the target battery cluster increases, the temperature difference to be adjusted is increased using the temperature difference adjustment redundancy value to cool the target battery cluster to a lower temperature, thereby avoiding multiple adjustments caused by a rapid rise in the battery cluster temperature. The more times the same battery cluster is cooled, the larger the temperature difference to be adjusted needs to be adjusted using the temperature difference adjustment redundancy value to cool the target battery cluster to a lower temperature.

[0058] The above embodiment takes into account the actual situation of the battery cluster, that is, the number of times the battery cluster performs cooling, and adjusts its cooling strategy by setting the temperature difference adjustment redundancy value, so as to cool it to a relatively low temperature and reduce the number of cooling times.

[0059] Corresponding to the cooling method of the above energy storage system, the embodiment of the present application also provides an energy storage system. Figure 3 , is a structural diagram of an energy storage system provided in an embodiment of the present application. The energy storage system may include: a first determination module 301, a second determination module 302 and a cooling module 303.

[0060] The first determining module 301 acquires temperature information of each battery cluster through a collection device, and determines a first battery cluster that needs to be cooled based on the temperature information.

[0061] The second determining module 302 calculates the cooling priority of each of the first battery clusters when at least two of the first battery clusters are included, and determines the first battery cluster with the highest cooling priority as the target battery cluster.

[0062] The cooling module 303 opens the second valve connecting the target battery cluster and the second liquid cooling unit, and closes the second valves of other battery clusters, so as to cool the target battery cluster through the second liquid cooling unit.

[0063] The first valve connecting each battery cluster to the first liquid cooling unit is always open, so that each battery cluster is cooled by the first liquid cooling unit.

[0064] Figure 4 This is a schematic diagram of the structure of an embodiment of the electrical equipment in this specification. The electrical equipment includes Figure 1 The energy storage system shown in Figure 1 is as follows. Figure 4 As shown, the electronic device may include at least one processor; and at least one memory communicatively connected to the processing unit, wherein the memory stores program instructions that can be executed by the processing unit, and the processor calls the program instructions to execute the cooling method of the energy storage system provided in this embodiment.

[0065] Figure 4 A block diagram is shown of an exemplary electronic device suitable for implementing embodiments of the present description. Figure 4 The electronic device shown is only an example and should not limit the functions and scope of use of the embodiments of this specification.

[0066] like Figure 4 As shown, the electronic device is implemented as a general-purpose computing device. Components of the electronic device may include, but are not limited to, one or more processors 410, a communication interface 420, a memory 430, and a communication bus 440 connecting different system components (including the memory 430, the communication interface 420, and the processor 410).

[0067] Communication bus 440 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor, or a local bus using any of a variety of bus architectures. Examples of these architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MAC) bus, the Enhanced ISA bus, the Video Electronics Standards Association (VESA) local bus, and the Peripheral Component Interconnection (PCI) bus.

[0068] Electronic devices typically include a variety of computer system readable media. These media can be any available media that can be accessed by the electronic device, including volatile and non-volatile media, removable and non-removable media.

[0069] Memory 430 may include computer-readable media in the form of volatile memory, such as random access memory (RAM) and / or cache memory. The electronic device may further include other removable or non-removable, volatile or non-volatile computer storage media. Memory 430 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of various embodiments of this specification.

[0070] A program / utility having a set (at least one) of program modules may be stored in memory 430. Such program modules include, but are not limited to, an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment. The program modules generally implement the functions and / or methods of the embodiments described herein.

[0071] The processor 410 executes various functional applications and data processing by running the programs stored in the memory 430, such as implementing the cooling method of the energy storage system provided in the embodiments shown in this specification.

[0072] An embodiment of this specification provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium stores computer instructions, and the computer instructions enable the computer to execute the cooling method of the energy storage system provided by the embodiment shown in this specification.

[0073] The foregoing description of this specification describes specific embodiments. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that described in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or the sequential order to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0074] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. Throughout this specification, "plurality" means at least two, such as two or three, unless otherwise specifically defined.

[0075] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of this specification includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of this specification belong.

[0076] The word "if," as used herein, may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to the determination" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)," depending on the context.

[0077] In the embodiments provided in this specification, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be through some interface, indirect coupling or communication connection of the device or unit, which may be electrical, mechanical or other forms.

[0078] In addition, the functional units in the various embodiments of this specification may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or hardware plus software functional units.

[0079] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit stored in a storage medium includes a number of instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) or a processor to execute some of the steps of the method described in various embodiments of this specification.

[0080] The above description is only a preferred embodiment of this specification and is not intended to limit this specification. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this specification should be included in the scope of protection of this specification.

Claims

1. A cooling method for an energy storage system, characterized in that: The energy storage system includes multiple battery clusters, each of which is connected to a first liquid cooling unit and a second liquid cooling unit via a valve. The cooling method of the energy storage system includes: Acquiring temperature information of each battery cluster through a collection device, and determining a first battery cluster that needs to be cooled based on the temperature information; When at least two first battery clusters are included, respectively calculating the cooling priority of each of the first battery clusters, and determining the first battery cluster with the highest cooling priority as the target battery cluster; opening the second valve connecting the target battery cluster and the second liquid cooling unit, and closing the second valves of other battery clusters, so as to cool the target battery cluster through the second liquid cooling unit; The first valve connecting each of the first battery clusters and the first liquid cooling unit is always open, so that each of the first battery clusters is cooled by the first liquid cooling unit.

2. The cooling method of the energy storage system according to claim 1, characterized in that: The determining, based on the temperature information, the first battery cluster that needs to be cooled includes: By comparing the maximum temperature difference of each battery cluster with a preset cooling temperature threshold, the battery cluster having the maximum temperature difference greater than the cooling temperature threshold is determined as the first battery cluster.

3. The cooling method of the energy storage system according to claim 1, characterized in that: The respectively calculating the cooling priority of each of the first battery clusters includes: respectively determining, for each of the first battery clusters, a first priority contribution value based on the accumulated temperature deviation value, a second priority contribution value based on the maximum temperature change rate, and a third priority contribution value based on the temperature deviation value; The cooling priority of each first battery cluster is determined according to the first priority contribution value, the second priority contribution value, and the third priority contribution value of each battery cluster.

4. The cooling method of the energy storage system according to claim 3, characterized in that: The method comprises: determining a first priority contribution value according to a maximum temperature difference of each of the first battery clusters, a time during which the maximum temperature of each of the battery clusters exceeds an average temperature, and a corresponding first coefficient; Determining a second priority contribution value by using a maximum temperature difference of each of the first battery clusters at a time interval and an average temperature difference of the energy storage system, as well as a corresponding second coefficient; A third priority contribution value is determined according to the maximum temperature difference of each of the first battery clusters and the corresponding third coefficient.

5. The cooling method of the energy storage system according to claim 1, characterized in that: After cooling the target battery cluster by the second liquid cooling unit, the method further includes: determining, based on the temperature information of the target battery cluster, whether the target battery cluster has achieved a cooling effect; When it is determined that the target battery cluster has achieved the cooling effect, the second valve connecting the target battery cluster and the second liquid cooling unit is closed, cooling of the target battery cluster by the second liquid cooling unit is stopped, and the first battery cluster with the next priority is re-determined as the target battery cluster, and is cooled by opening the second valve connecting the target battery cluster and the second liquid cooling unit.

6. The cooling method of the energy storage system according to claim 5, characterized in that: The determining whether the target battery cluster has achieved a cooling effect includes: comparing the maximum temperature difference of the target battery cluster with a preset cooling temperature threshold; When the maximum temperature difference is lower than the cooling temperature threshold, it is determined that the target battery cluster has achieved a cooling effect.

7. The cooling method of the energy storage system according to claim 5, characterized in that: The method of determining whether the target battery cluster has achieved a cooling effect further includes: Calculating a minimum operating time based on the temperature information, the shortest operating time being the time it takes for the second liquid cooling unit to cool the target battery cluster to ensure that the target battery cluster achieves a cooling effect; timing the time during which the target battery cluster turns on the second valve to perform cooling; When the actual cooling time of the target battery cluster by the second liquid cooling unit reaches the shortest operating time, it is determined that the cooling effect of the target battery cluster has been achieved.

8. The cooling method of the energy storage system according to claim 7, characterized in that: The calculating the shortest operating time according to the temperature information includes: Determining a temperature difference to be adjusted based on the maximum temperature difference of the target battery cluster and a cooling temperature threshold; determining a first amount of heat required to be released by the target battery cluster to achieve a cooling effect based on the temperature difference to be adjusted, the total mass of the target battery cluster, and the specific heat capacity of the battery cluster; Determining a second amount of heat that the second liquid cooling unit needs to absorb when the target battery cluster achieves a cooling effect based on the specific heat capacity of the coolant in the second liquid cooling unit, the mass flow rate of the coolant in a single battery cluster, the temperature difference between the coolant inlet and outlet water of the single battery cluster, and the heat generation rate of the target battery cluster; The shortest operating time is determined according to the first heat amount and the second heat amount.

9. The cooling method of the energy storage system according to claim 5, characterized in that: After determining that the target battery cluster has achieved the cooling effect, the method further includes: Count the number of times each battery cluster needs to be cooled; When the number of times any battery cluster needs to be cooled reaches a preset number threshold, the second valve of the target battery cluster is continuously opened and an alarm message is reported.

10. The cooling method of the energy storage system according to claim 8, characterized in that: The method further comprises determining a temperature difference to be adjusted based on the maximum temperature difference of the target battery cluster and a cooling temperature threshold: Determining the temperature difference to be adjusted according to the maximum temperature difference of the target battery cluster, the cooling temperature threshold, and a temperature difference adjustment redundancy value; The temperature difference adjustment redundancy value is used to correct and adjust the temperature difference to be adjusted determined by the maximum temperature difference and the cooling temperature threshold.

11. The cooling method of the energy storage system according to claim 10, characterized in that: Adjusting the temperature difference to be adjusted by using the temperature difference adjustment redundancy value includes: As the number of times the same battery cluster is cooled as the target battery cluster increases, the temperature difference to be adjusted is increased by using the temperature difference adjustment redundancy value; The more times the same battery cluster is cooled, the larger the temperature difference to be adjusted will be by adjusting the temperature difference redundancy value.

12. The cooling method for an energy storage system according to any one of claims 1 to 11, characterized in that: The method further comprises: Determining the average temperature and / or maximum temperature difference of the target battery cluster according to the temperature information, the method comprising: determining an average temperature of the energy storage system according to the maximum temperature of each battery cluster; The maximum temperature difference of each battery cluster is determined according to the maximum temperature of each battery cluster and the average temperature of the energy storage system.

13. An energy storage system, characterized in that: The energy storage system includes a plurality of battery clusters, each of which is connected to a first liquid cooling unit and a second liquid cooling unit via a valve. The system includes: a first determining module, which acquires temperature information of each battery cluster through a collection device and determines a first battery cluster that needs to be cooled based on the temperature information; a second determining module, when at least two first battery clusters are included, calculating the cooling priority of each of the first battery clusters respectively, and determining the first battery cluster with the highest cooling priority as the target battery cluster; a cooling module, which opens the second valve connecting the target battery cluster and the second liquid cooling unit, and closes the second valves of other battery clusters, so as to cool the target battery cluster through the second liquid cooling unit; The first valve connecting each battery cluster to the first liquid cooling unit is always open, so that each battery cluster is cooled by the first liquid cooling unit.

14. The energy storage system according to claim 13, characterized in that: The first determining module determines a first battery cluster that needs to be cooled based on the temperature information, including: By comparing the maximum temperature difference of each battery cluster with a preset cooling temperature threshold, the battery cluster having the maximum temperature difference greater than the cooling temperature threshold is determined as the first battery cluster.

15. The energy storage system according to claim 13, characterized in that: The second determining module calculates the cooling priority of each of the first battery clusters respectively, including: respectively determining, for each of the first battery clusters, a first priority contribution value based on the accumulated temperature deviation value, a second priority contribution value based on the maximum temperature change rate, and a third priority contribution value based on the temperature deviation value; The cooling priority of each first battery cluster is determined according to the first priority contribution value, the second priority contribution value, and the third priority contribution value of each battery cluster.

16. The energy storage system according to claim 13, characterized in that: After the cooling module cools the target battery cluster through the second liquid cooling unit, the cooling module further includes: determining, based on the temperature information of the target battery cluster, whether the target battery cluster has achieved a cooling effect; When it is determined that the target battery cluster has achieved the cooling effect, the second valve connecting the target battery cluster and the second liquid cooling unit is closed, cooling of the target battery cluster by the second liquid cooling unit is stopped, and the first battery cluster with the next priority is re-determined as the target battery cluster, and is cooled by opening the second valve connecting the target battery cluster and the second liquid cooling unit.

17. The energy storage system according to claim 16, characterized in that: The determining whether the target battery cluster has achieved a cooling effect includes: comparing the maximum temperature difference of the target battery cluster with a preset cooling temperature threshold; When the maximum temperature difference is lower than the cooling temperature threshold, it is determined that the target battery cluster has achieved a cooling effect.

18. The energy storage system according to claim 16, characterized in that: The determining whether the target battery cluster has achieved a cooling effect further includes: Calculating a minimum operating time based on the temperature information, the shortest operating time being the time it takes for the second liquid cooling unit to cool the target battery cluster to ensure that the target battery cluster achieves a cooling effect; timing the time during which the target battery cluster turns on the second valve to perform cooling; When the actual cooling time of the target battery cluster by the second liquid cooling unit reaches the shortest operating time, it is determined that the cooling effect of the target battery cluster has been achieved.

19. An energy storage device comprising the energy storage system according to any one of claims 13 to 18, and configured to execute the cooling method for the energy storage system according to any one of claims 1 to 12.

Images