Energy storage device and thermal management method of energy storage device

Abstract

The embodiment of the present invention relates to the technical field of energy storage and heat dissipation, and discloses an energy storage device and a thermal management method for the energy storage device. In the present invention, an axial flow fan is arranged at the junction between the battery cell groups in the energy storage device to improve the flow of the coolant near the battery cell group in the energy storage device, effectively improve the fluidity of the coolant near the battery cell group, thereby reducing the coolant temperature near the battery cell group and improving the heat dissipation efficiency around the battery cell group; and the start and shut down of the axial flow fan are dynamically controlled according to the temperature of the coolant and the temperature of the battery cell group through the BMS system, which is conducive to dynamically adjusting the heat dissipation capacity of the energy storage system according to different heat dissipation conditions, so that the axial flow fan is started to speed up the circulation of the coolant when the heat dissipation efficiency needs to be improved, and the axial flow fan is shut down to save costs when the heat dissipation efficiency is high.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of energy storage and heat dissipation, and in particular to an energy storage device and a thermal management method for the energy storage device. Background Art

[0002] The energy storage system is equipped with multiple energy storage devices, which include multiple battery cells connected in series. Since the battery cells generate heat during the charging and discharging process, the battery cell temperature rises, which can easily lead to reduced charging and discharging efficiency and shorten the battery cell life, and may even cause thermal runaway and fire. Since the battery cell temperature is too high, the battery cell cannot maintain a normal working state, so an external cooling system is required to manage the battery cell thermally.

[0003] The common cooling system in energy storage devices is an immersion liquid cooling system, which fills the energy storage pack with an insulating cooling medium, and the cooling medium is in direct contact with the battery cell for heat exchange, thereby reducing the temperature of the battery cell. However, the inventors found that there are at least the following problems in the related art: the cooling medium of the immersion liquid cooling system has weak fluidity in the energy storage system, and there are dead zones, that is, there are some areas where the cooling medium cannot flow, which will lead to uneven cooling effects of the coolant in different areas, low utilization of the cooling medium, and poor cooling effects of the cooling system. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide an energy storage device and a thermal management method for the energy storage device, so as to improve the fluidity of the cooling medium of the immersion liquid cooling system in the energy storage device, thereby improving the cooling efficiency of the immersion liquid cooling system.

[0005] To solve the above technical problems, an embodiment of the present invention provides an energy storage device, including: a coolant, a shell, a supporting structure, a plurality of battery cell groups, an axial flow fan, and a BMS system; the coolant fills the interior of the shell; the supporting structure is fixedly connected to the inner side of the shell, and is used to fix the plurality of battery cell groups; the axial flow fan is arranged at the junction between the plurality of battery cell groups and at the bottom corner inside the shell, and the axial flow fan is fixedly connected to the inner side of the shell; the output direction of the axial flow fan is consistent with the flow direction of the coolant; the BMS system is electrically connected to the axial flow fan, and the BMS system is used to control the start and stop of the axial flow fan according to the temperature of the coolant and the temperature of the plurality of battery cell groups.

[0006] An embodiment of the present invention also provides a thermal management method for an energy storage device, including: a BMS system applied to the energy storage device as described above, comprising: obtaining temperature data of a battery cell group; and starting an axial flow fan when the temperature of the battery cell group is greater than a threshold temperature of the battery cell group.

[0007] In the embodiment of the present invention, an axial flow fan is provided at the junction between the battery cell groups in the energy storage device to improve the flow of the coolant near the battery cell groups in the energy storage device, effectively improve the fluidity of the coolant near the battery cell groups, thereby reducing the coolant temperature near the battery cell groups and improving the heat dissipation efficiency around the battery cell groups; and, by providing an axial flow fan at the bottom corner inside the shell, it is beneficial to promote the flow of the coolant at the bottom corner inside the shell, improve the flow and circulation of the coolant in the dead corner inside the energy storage device, and improve the heat dissipation efficiency of the energy storage device and enhance the heat dissipation capacity of the energy storage device; in addition, the output direction of the axial flow fan is consistent with the flow direction of the coolant, which is beneficial to accelerate the circulation of the coolant and improve the heat dissipation efficiency of the energy storage device; further, the start and stop of the axial flow fan is dynamically controlled by the BMS system according to the temperature of the coolant and the temperature of the battery cell group, which is beneficial to dynamically adjust the heat dissipation capacity of the energy storage system according to different heat dissipation conditions, so that the axial flow fan is started when the heat dissipation efficiency needs to be improved to accelerate the circulation of the coolant, and the axial flow fan is turned off when the heat dissipation efficiency is high to save costs.

[0008] In some embodiments, the energy storage device also includes a liquid cooling temperature sensor, which is used to detect the temperature of the coolant; the liquid cooling temperature sensor is arranged in the area with the highest coolant temperature and the area with the fastest flow rate of the coolant inside the shell; the liquid cooling temperature sensor is electrically connected to the BMS system to transmit the temperature of the coolant to the BMS system.

[0009] In some embodiments, the area with the highest coolant temperature inside the shell includes the junction between the multiple groups of battery cells; the area with the fastest coolant flow rate includes the bottom corner inside the shell.

[0010] In some embodiments, the energy storage device further includes a battery cell temperature sensor, which is disposed at the top of each battery cell group; the battery cell temperature sensor is electrically connected to the BMS system to transmit the temperature of the battery cell group to the BMS system.

[0011] In some embodiments, the length of the support structure is smaller than the length of the battery cell group; and / or the bottom of the support structure is hollow.

[0012] In some embodiments, the plurality of battery cell groups are spaced apart from the inner wall of the housing by a preset distance, and the length of the preset distance is equal to the impeller diameter of the axial flow fan.

[0013] In some embodiments, the axial flow fan includes two impellers; the two impellers have the same direction of rotation; the two impellers are arranged in close proximity, or the two impellers are arranged at a preset distance.

[0014] In some embodiments, the method further includes: acquiring temperature data of the coolant when the temperature of the battery cell group is lower than a threshold temperature of the battery cell group; and starting the axial flow fan when the temperature of the coolant is higher than a threshold temperature of the coolant.

[0015] In some embodiments, the method further includes: when the temperature of the coolant is less than the coolant threshold temperature, calculating the temperature difference of the coolant in different areas of the energy storage device according to the temperature of the coolant; and when the temperature difference of the coolant is greater than the preset temperature difference of the coolant, starting the axial flow fan.

[0016] In some embodiments, the rotation speed of the axial fan includes three speeds: low speed, medium speed, and high speed; when any one of the following conditions is met: the temperature of the battery cell group is greater than the battery cell group threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant, after the axial flow fan is started, the rotation speed of the axial flow fan is adjusted to low speed; when any two of the following conditions are met: the temperature of the battery cell group is greater than the battery cell group threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant, after the axial flow fan is started, the rotation speed of the axial flow fan is adjusted to medium speed; when the three conditions of the temperature of the battery cell group is greater than the battery cell group threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant are met at the same time, after the axial flow fan is started, the rotation speed of the axial flow fan is adjusted to high speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0018] Figure 1 is a schematic diagram of the structure of an energy storage device provided in one embodiment of the present application;

[0019] Figure 2 This is a schematic diagram of the location of the axial flow fan of the energy storage device provided in one embodiment of the present application;

[0020] Figure 3 It is a flow chart of a thermal management method for an energy storage device provided in one embodiment of the present application;

[0021] Figure 4 is another flow chart of a thermal management method for an energy storage device provided in one embodiment of the present application;

[0022] Figure 5 It is a structural schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0023] Since the cooling medium of the immersion liquid cooling system has weak fluidity in the energy storage system and there are flow dead zones, that is, the cooling medium cannot flow in some areas, which will cause uneven cooling effects of the coolant in different areas, low utilization of the cooling medium, and poor cooling effect of the cooling system. Therefore, an energy storage device that improves the cooling efficiency of the immersion liquid cooling system and a thermal management method of the energy storage device are needed to solve the above problems.

[0024] To make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the embodiments of the present invention, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and the changes and modifications based on the following embodiments, the technical scheme claimed in the present application can be implemented. The division of the following embodiments is for the convenience of description, and the specific implementation of the present invention should not be construed as any limitation, and the various embodiments can be combined and referenced with each other without contradiction.

[0025] One embodiment of the present invention relates to an energy storage device that can be used in an immersion liquid-cooled energy storage system. The energy storage device includes: a coolant, a shell, a support structure, multiple battery cell groups, an axial flow fan, and a BMS system; the coolant fills the inside of the shell; the support structure is fixedly connected to the inner side of the shell, and is used to fix the multiple battery cell groups; the axial flow fan is arranged at the junction between the multiple battery cell groups and at the bottom corner inside the shell, and the axial flow fan is fixedly connected to the inner side of the shell; the output direction of the axial flow fan is consistent with the flow direction of the coolant; the BMS system is electrically connected to the axial flow fan, and the BMS system is used to control the start and stop of the axial flow fan according to the temperature of the coolant and the temperature of the multiple battery cell groups. The detailed structure of the energy storage device of an embodiment of the present invention is specifically described below. The following content is only the implementation details provided for easy understanding and is not necessary for the implementation of this solution.

[0026] like Figure 1As shown, the energy storage device described in an embodiment of the present invention includes: a coolant, a shell 001, a support structure 002, a plurality of battery cell groups 003, an axial flow fan 004, and a BMS system; the coolant fills the interior of the shell 001; the support structure 002 is fixedly connected to the inner side of the shell 001, and is used to fix the plurality of battery cell groups 003; the axial flow fan 004 is arranged at the junction between the plurality of battery cell groups 003 and at the bottom corner inside the shell 001, and the axial flow fan 004 is fixedly connected to the inner side of the shell 001; the output direction of the axial flow fan 004 is consistent with the flow direction of the coolant; the BMS system is electrically connected to the axial flow fan 004, and the BMS system is used to control the start and stop of the axial flow fan 004 according to the temperature of the coolant and the temperature of the plurality of battery cell groups 003.

[0027] In some embodiments of the present invention, the energy storage device further includes a liquid cooling temperature sensor, which is used to detect the temperature of the coolant; the liquid cooling temperature sensor is arranged in the area with the highest coolant temperature and the area with the fastest flow rate of the coolant inside the shell; the liquid cooling temperature sensor is electrically connected to the BMS system to transmit the temperature of the coolant to the BMS system. The embodiment of the present invention provides a temperature sensor at the position where the axial fan is set in the energy storage device, and further controls the start and stop of the axial fan according to the temperature of the coolant at the position of the axial fan through the BMS system temperature sensor, thereby dynamically controlling the axial fan according to the temperature in the energy storage device, thereby improving the stability of the energy storage system and the temperature balance.

[0028] In some specific embodiments of the present invention, the liquid-cooled temperature sensor may be a thermistor; further, the thermistor is a thermistor. The thermistor may be any one of a negative temperature coefficient thermistor (NTC), a positive temperature coefficient thermistor (PTC) or a critical temperature resistor (CTR). In addition, the shape of the thermistor may be a disc or a cylinder; the sensitivity of the thermistor may be a high sensitivity type or a low sensitivity type; the heating method of the thermistor is a direct heating type. It should be noted that those skilled in the art may adjust the type of the liquid-cooled temperature sensor according to the specific needs of the actual application, or set the specific shape, sensitivity type and heating method of the liquid-cooled temperature sensor, and the present invention is not limited here.

[0029] In some embodiments of the present invention, the area with the highest coolant temperature inside the shell includes the junction between the multiple groups of battery cells; the area with the fastest flow rate of the coolant includes the bottom corner inside the shell. Among them, the junction between the multiple groups of battery cells is a position that is equal to the distance between each two adjacent groups of battery cells. Specifically, the position that is equal to the distance between each two adjacent groups of battery cells can be a position that is equal to the distance between the bottom surface of the first group of battery cells and the top of the second group of battery cells. It should be noted that those skilled in the art can adjust the specific setting position of the fan according to the specific needs of the actual application, and can also increase or decrease the specific position of the fan setting on the basis of the present invention, and the present invention is not limited here. In the embodiment of the present invention, a liquid cooling temperature sensor is set corresponding to the position where the axial flow fan is set, so that the BMS system can start and shut down the axial flow fan more accurately according to the temperature of the area inside the shell that is easy to accumulate heat and the area that is not easy to accumulate heat, so that the thermal management of the energy storage system has greater flexibility.

[0030] In some embodiments of the present invention, Figure 2 As shown, multiple axial flow fans 004 are provided at the junctions between the multiple groups of battery core groups; and multiple axial flow fans 004 are provided at the bottom corners inside the housing 001. Specifically, the axial flow fan 004 provided at the junctions between the battery core groups is the first axial flow fan 004, and the fan provided at the bottom corner inside the housing 001 is the second axial flow fan 004. The number of the first axial flow fans 004 and the second axial flow fans 004 are equal. Specifically, the number of the battery core groups is 2, and the two groups of battery core groups are separated by a preset distance between the battery core groups; the number of the first axial flow fans 004 and the second axial flow fans 004 are both 4; four of the first axial flow fans 004 are respectively provided at the four inner side wall connections of the housing 001; and four of the second axial flow fans 004 are respectively provided at the four bottom corners inside the housing 001. It should be noted that those skilled in the art can adjust the specific setting position of the fan according to the specific needs of the actual application, and can also increase or decrease the specific number of fan settings on the basis of the present invention, and the present invention is not limited here.

[0031] In some embodiments of the present invention, the energy storage device further includes a cell temperature sensor, which is disposed at the top of each cell group; the cell temperature sensor is electrically connected to the BMS system to transmit the temperature of the cell group to the BMS system. In the embodiments of the present invention, by disposing a cell temperature sensor at the top of the cell and connecting the cell temperature sensor to the BMS system, the BMS system can more accurately control the opening and closing of the axial fan according to the detected cell temperature, so that the thermal management of the energy storage system has greater flexibility.

[0032] In some specific embodiments of the present invention, the battery cell temperature sensor may be a thermistor; further, the thermistor is a thermistor. The thermistor may be any one of a negative temperature coefficient thermistor (NTC), a positive temperature coefficient thermistor (PTC) or a critical temperature resistor (CTR). In addition, the shape of the thermistor may be a disc or a cylinder; the sensitivity of the thermistor may be a high sensitivity type or a low sensitivity type; the heating method of the thermistor is a direct heating type. It should be noted that those skilled in the art may adjust the type of the battery cell temperature sensor according to the specific needs of the actual application, or set the specific shape, sensitivity type and heating method of the battery cell temperature sensor, and the present invention is not limited here.

[0033] In some embodiments of the present invention, a plurality of the battery cell temperature sensors are arranged at the top of each battery cell group, and the battery cell temperature sensors are evenly distributed at the top of each battery cell group. In the embodiments of the present invention, by evenly arranging a plurality of battery cell temperature sensors at the top of the battery cell temperature sensors, the temperature of the battery cell group detected is more accurate, and the temperature accuracy of the entire battery cell group detected by the battery cell temperature sensors is improved, thereby improving the control accuracy of turning the axial flow fan on and off.

[0034] In some specific embodiments of the present invention, four battery cell temperature sensors are arranged at the top of each battery cell group, and the four battery cell temperature sensors are respectively distributed in the four quadrants divided by the top plane of the battery cell group according to the center point, or the four battery cell temperature sensors are equally spaced on the top plane of the battery cell group.

[0035] In some embodiments of the present invention, the length of the support structure is less than the length of the battery cell group; and / or the bottom of the support structure is hollowed out. The embodiments of the present invention reduce the contact area between the support structure and the battery cell group so that the battery cell group can be in contact with the coolant to a greater extent, thereby improving the heat dissipation effect of the energy storage system and effectively reducing the battery cell temperature.

[0036] In some embodiments of the present invention, the multiple groups of battery cells are spaced apart from the inner wall of the shell by a preset distance, and the length of the preset distance is equal to the impeller diameter of the axial flow fan. The embodiments of the present invention are arranged at a preset distance between the battery cell group and the inner wall of the shell, which is conducive to improving the fluidity of the coolant inside the energy storage device, increasing the contact area between the battery cell and the coolant, and enhancing the heat dissipation capacity of the energy storage device; in addition, the preset distance is equal to the impeller diameter of the axial flow fan, which can ensure that the coolant accelerated by the axial flow fan will not slow down in the process of passing through the battery cell group and the inner wall of the shell due to the preset distance being too small, further improving the flow capacity of the coolant and accelerating the circulation of the coolant. It should be noted that those skilled in the art can adjust the size of the preset distance according to the specific needs of the actual application, and the present invention is not limited here.

[0037] In some embodiments of the present invention, the shell is provided with a water inlet and a water outlet; the water inlet and the water outlet are located on the same side of the shell; the water inlet and the water outlet are arranged vertically, and the axial flow fan arranged at the junction between the multiple groups of battery cells is located in the area between the water inlet and the water outlet. In the embodiments of the present invention, an axial flow fan is arranged at a position between the water inlet and the water outlet, so that the water inlet and outlet rates are consistent during the circulation of the coolant, thereby avoiding the imbalance of the internal temperature of the energy storage device caused by the inconsistent coolant inlet and outlet rates.

[0038] In some embodiments of the present invention, a water inlet and a water outlet communicating with the interior of the shell are provided on the outside of the shell, and the water inlet and the water outlet are both connected to a cooling device outside the energy storage device. It should be noted that those skilled in the art can adjust the specific positions of the water inlet and the water outlet according to the specific requirements of the actual application, and the present invention does not limit this.

[0039] In some embodiments of the present invention, the number of the battery cell groups is 2, and the spacing distance between the two battery cell groups is greater than the longitudinal distance between the water inlet and the water outlet; the longitudinal distance between the axial flow fan arranged at the junction between the multiple battery cell groups and the water inlet is equal to the longitudinal distance between the axial flow fan and the water outlet; or, the longitudinal distances between the axial flow fan and the two battery cell groups are equal.

[0040] In some embodiments of the present invention, the axial flow fan includes two impellers; the two impellers have the same direction of rotation; the two impellers are arranged in close proximity, or the two impellers are arranged at a preset distance. It should be noted that those skilled in the art can adjust the interval between the impellers according to the specific needs of the actual application, and the present invention is not limited here. In an embodiment of the present invention, two impellers in the same direction are arranged in the axial flow fan, and the two impellers in the same direction improve the operating efficiency of the axial flow fan, thereby accelerating the circulation of the coolant; in addition, when one impeller in the fan fails, the other impeller can continue to operate to ensure the flow of the coolant, thereby improving the stability of the thermal management of the energy storage system.

[0041] In an embodiment of the present invention, an axial flow fan is provided at the junction between the battery cell groups in the energy storage device to improve the flow of the coolant near the battery cell groups in the energy storage device, effectively improve the fluidity of the coolant near the battery cell groups, thereby reducing the coolant temperature near the battery cell groups and improving the heat dissipation efficiency around the battery cell groups; and, by providing an axial flow fan at the bottom corner inside the shell, it is beneficial to promote the flow of the coolant at the bottom corner inside the shell, improve the flow and circulation of the coolant in the dead corner inside the energy storage device, and improve the heat dissipation efficiency of the energy storage device and enhance the heat dissipation capacity of the energy storage device; in addition, the output direction of the axial flow fan is consistent with the flow direction of the coolant, which is beneficial to accelerate the circulation of the coolant and improve the heat dissipation efficiency of the energy storage device; further, the start and stop of the axial flow fan is dynamically controlled by the BMS system according to the temperature of the coolant and the temperature of the battery cell group, which is beneficial to dynamically adjust the heat dissipation capacity of the energy storage system according to different heat dissipation conditions, so that the axial flow fan is started when the heat dissipation efficiency needs to be improved to accelerate the circulation of the coolant, and the axial flow fan is turned off when the heat dissipation efficiency is high to save costs.

[0042] The examples mentioned in the above embodiments can be freely combined, and any combination can be understood as an embodiment. The "embodiment" or "example" appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It can be understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0043] In summary, specific embodiments of the subject matter have been described. Other embodiments are within the scope of the appended claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results.

[0044] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In addition, the term "plurality" refers to more than two (including two), and similarly, "multiple groups" refers to more than two (including two).

[0045] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0046] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0047] Another embodiment of the present invention relates to a thermal management method for an energy storage device, which can be applied to a BMS system of the above energy storage device. The thermal management method comprises: obtaining temperature data of a battery cell group; and starting an axial flow fan when the temperature of the battery cell group is greater than a threshold temperature of the battery cell group. In an embodiment of the present invention, an axial flow fan is provided at the junction between the battery cell groups in the energy storage device to improve the flow of the coolant near the battery cell groups in the energy storage device, effectively improve the fluidity of the coolant near the battery cell groups, thereby reducing the coolant temperature near the battery cell groups and improving the heat dissipation efficiency around the battery cell groups; and, by providing an axial flow fan at the bottom corner inside the shell, it is beneficial to promote the flow of the coolant at the bottom corner inside the shell, improve the flow and circulation of the coolant in the dead corner inside the energy storage device, and improve the heat dissipation efficiency of the energy storage device and enhance the heat dissipation capacity of the energy storage device; in addition, the output direction of the axial flow fan is consistent with the flow direction of the coolant, which is beneficial to accelerate the circulation of the coolant and improve the heat dissipation efficiency of the energy storage device; further, the start and stop of the axial flow fan is dynamically controlled by the BMS system according to the temperature of the coolant and the temperature of the battery cell group, which is beneficial to dynamically adjust the heat dissipation capacity of the energy storage system according to different heat dissipation conditions, so that the axial flow fan is started when the heat dissipation efficiency needs to be improved to accelerate the circulation of the coolant, and the axial flow fan is turned off when the heat dissipation efficiency is high to save costs. The implementation details of the thermal management method for an energy storage device according to an embodiment of the present invention are described in detail below. The following content is only provided for easy understanding of the implementation details and is not necessary for implementing the present solution.

[0048] like Figure 3 As shown, in step 101, the BMS system obtains temperature data of the battery cell group.

[0049] In step 102, when the temperature of the battery cell group is greater than a threshold temperature of the battery cell group, an axial flow fan is started.

[0050] In some embodiments of the present invention, the temperature data of the battery cell group is obtained at intervals of a first preset time; after the axial flow fan is started, the axial flow fan is turned off after an interval of a second preset time. It should be noted that the first preset time and the second preset time can be set accordingly according to actual application requirements, and the present invention does not limit this. The embodiment of the present invention obtains temperature data at intervals of a preset time and determines whether the axial flow fan needs to be turned on or off, so that the coolant inside the energy storage system can always be guaranteed to circulate efficiently, while also preventing the fan from continuously running and generating heat that affects the heat dissipation of the energy storage system.

[0051] In some embodiments of the present invention, when the temperature of the battery cell group is lower than the battery cell group threshold temperature, the temperature data of the coolant is acquired; when the temperature of the coolant is higher than the coolant threshold temperature, the axial flow fan is started.

[0052] In some embodiments of the present invention, when the temperature of the coolant is lower than the coolant threshold temperature, the temperature difference of the coolant in different areas of the energy storage device is calculated according to the temperature of the coolant; when the temperature difference of the coolant is greater than the preset temperature difference of the coolant, the axial flow fan is started.

[0053] In some specific embodiments of the present invention, Figure 4 As shown, in step 201, the BMS system obtains the temperature data of the battery cell group at a first preset time interval.

[0054] In step 202 , the BMS system determines whether the temperature of the battery cell group is greater than the threshold temperature of the battery cell group. If so, the process jumps to step 205 , and turns off the axial flow fan after a second preset time interval; if not, the process jumps to step 203 .

[0055] In step 203 , the BMS system obtains the temperature data of the coolant and determines whether the temperature of the coolant is greater than the coolant threshold temperature. If so, the process jumps to step 205 ; if not, the process jumps to step 204 .

[0056] In step 204, the BMS system calculates the temperature difference of the coolant in different areas of the energy storage device according to the temperature of the coolant, and determines whether the temperature difference of the coolant is greater than the preset temperature difference of the coolant. If so, jump to step 205; if not, jump to step 201.

[0057] In step 205, the axial flow fan is started, and then turned off after a second predetermined time interval.

[0058] In some embodiments of the present invention, the rotation speed of the axial flow fan includes three speeds: low speed, medium speed, and high speed; when any one of the following conditions is met: the temperature of the battery cell group is greater than the battery cell group threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant, after the axial flow fan is started, the rotation speed of the axial flow fan is adjusted to low speed; when any two of the following conditions are met: the temperature of the battery cell group is greater than the battery cell group threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant, after the axial flow fan is started, the rotation speed of the axial flow fan is adjusted to medium speed; when the three conditions of the temperature of the battery cell group is greater than the battery cell group threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant are met at the same time, after the axial flow fan is started, the rotation speed of the axial flow fan is adjusted to high speed.

[0059] In an embodiment of the present invention, an axial flow fan is provided at the junction between the battery cell groups in the energy storage device to improve the flow of the coolant near the battery cell groups in the energy storage device, effectively improve the fluidity of the coolant near the battery cell groups, thereby reducing the coolant temperature near the battery cell groups and improving the heat dissipation efficiency around the battery cell groups; and, by providing an axial flow fan at the bottom corner inside the shell, it is beneficial to promote the flow of the coolant at the bottom corner inside the shell, improve the flow and circulation of the coolant in the dead corner inside the energy storage device, and improve the heat dissipation efficiency of the energy storage device and enhance the heat dissipation capacity of the energy storage device; in addition, the output direction of the axial flow fan is consistent with the flow direction of the coolant, which is beneficial to accelerate the circulation of the coolant and improve the heat dissipation efficiency of the energy storage device; further, the start and stop of the axial flow fan is dynamically controlled by the BMS system according to the temperature of the coolant and the temperature of the battery cell group, which is beneficial to dynamically adjust the heat dissipation capacity of the energy storage system according to different heat dissipation conditions, so that the axial flow fan is started when the heat dissipation efficiency needs to be improved to accelerate the circulation of the coolant, and the axial flow fan is turned off when the heat dissipation efficiency is high to save costs.

[0060] The steps of the above method are divided only for the purpose of clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent; adding insignificant modifications to the algorithm or process or introducing insignificant designs without changing the core design of the algorithm and process are all within the scope of protection of this patent.

[0061] In addition, the examples mentioned in the above embodiments can be freely combined, and any combination can be understood as an embodiment. The "embodiment" or "example" appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It can be understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0062] It is not difficult to find that this embodiment is a method embodiment corresponding to the above-mentioned device embodiment, and this embodiment can be implemented in conjunction with the above-mentioned device embodiment. The relevant technical details mentioned in the above-mentioned device embodiment are still valid in this embodiment, and in order to reduce repetition, they are not repeated here. Accordingly, the relevant technical details mentioned in this embodiment can also be applied to the above-mentioned device embodiment.

[0063] Another embodiment of the present invention relates to an electronic device, such as Figure 5 As shown, it includes at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute a thermal management method for an energy storage device as described above.

[0064] Among them, the memory and the processor are connected in a bus manner, and the bus may include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors and memories together. The bus can also connect various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on a transmission medium. The data processed by the processor is transmitted on a wireless medium via an antenna, and further, the antenna also receives data and transmits the data to the processor.

[0065] The processor is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory can be used to store data used by the processor when performing operations.

[0066] Another embodiment of the present invention relates to a computer-readable storage medium storing a computer program, which implements the above method embodiment when executed by a processor.

[0067] That is, those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0068] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes may be made in form and detail without departing from the spirit and scope of the present invention.

Claims

1. An energy storage device, characterized in that: include: Coolant, housing, support structure, multiple battery packs, axial fans, BMS system; The coolant fills the interior of the housing; The support structure is fixedly connected to the inner side of the shell and is used to fix the multiple groups of battery cells; The axial flow fan is arranged at the junction between the multiple groups of battery cores and at the bottom corner inside the shell, and the axial flow fan is fixedly connected to the inner side of the shell; the output direction of the axial flow fan is consistent with the flow direction of the coolant; The BMS system is electrically connected to the axial flow fan, and the BMS system is used to control the start and stop of the axial flow fan according to the temperature of the coolant and the temperature of the multiple groups of battery cells; The axial flow fan arranged at the junction between the battery cell groups is a first axial flow fan; the fan arranged at the bottom corner inside the housing is a second axial flow fan; The number of the first axial flow fans and the number of the second axial flow fans are both 4, and the four first axial flow fans are respectively arranged at the four inner side wall connection points of the housing; the four second axial flow fans are respectively arranged at the four bottom corners inside the housing; The shell is provided with a water inlet and a water outlet; the water inlet and the water outlet are located on the same side of the shell; the water inlet and the water outlet are arranged up and down, and the first axial flow fan is located in the area between the water inlet and the water outlet; The number of the battery cell groups is 2, the two battery cell groups are arranged up and down, and the two battery cell groups are separated by a preset distance, and the distance between the two battery cell groups is greater than the longitudinal distance between the water inlet and the water outlet; A longitudinal distance between the first axial flow fan and the water inlet is equal to a longitudinal distance between the first axial flow fan and the water outlet.

2. The energy storage device according to claim 1, characterized in that: The energy storage device further includes a liquid cooling temperature sensor, which is used to detect the temperature of the coolant; The liquid cooling temperature sensor is arranged in the area where the coolant temperature is the highest and the area where the coolant flow rate is the fastest inside the shell; The liquid cooling temperature sensor is electrically connected to the BMS system to transmit the temperature of the coolant to the BMS system.

3. The energy storage device according to claim 2, characterized in that: The area with the highest coolant temperature inside the shell includes the junction between the multiple groups of battery cells; the area with the fastest coolant flow rate includes the bottom corner inside the shell.

4. The energy storage device according to claim 1, characterized in that: The energy storage device further includes a battery cell temperature sensor, which is disposed at the top of each battery cell group; The battery cell temperature sensor is electrically connected to the BMS system to transmit the temperature of the battery cell group to the BMS system.

5. The energy storage device according to claim 1, characterized in that: The multiple groups of battery cores are spaced apart from the inner wall of the housing by a preset distance, and the length of the preset distance is equal to the diameter of the impeller of the axial flow fan.

6. The energy storage device according to claim 1, characterized in that: The axial flow fan comprises two impellers; the two impellers have the same direction of rotation; The two impellers are arranged close to each other, or the two impellers are arranged with a preset distance between them.

7. A thermal management method for an energy storage device, applied to a BMS system of an energy storage device as claimed in any one of claims 1 to 6, characterized in that: include: Get the temperature data of the battery pack; When the temperature of the battery cell group is greater than a threshold temperature of the battery cell group, the axial flow fan is started.

8. The thermal management method of the energy storage device according to claim 7, characterized in that: The method further comprises: When the temperature of the battery cell group is lower than the threshold temperature of the battery cell group, obtaining temperature data of the coolant; When the temperature of the coolant is greater than a coolant threshold temperature, the axial flow fan is started.

9. The thermal management method of the energy storage device according to claim 8, characterized in that: The method further comprises: When the temperature of the coolant is lower than the coolant threshold temperature, calculating the temperature difference of the coolant in different areas of the energy storage device according to the temperature of the coolant; When the temperature difference of the coolant is greater than a preset temperature difference of the coolant, the axial flow fan is started.

10. The thermal management method of the energy storage device according to claim 9, characterized in that: The rotation speed of the axial flow fan includes three speeds: low speed, medium speed and high speed; When any one of the following conditions is satisfied: the temperature of the battery pack is greater than the battery pack threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant, after starting the axial flow fan, adjusting the speed of the axial flow fan to a low speed; When any two of the following conditions are met: the temperature of the battery pack is greater than the battery pack threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the preset temperature difference of the coolant, after starting the axial flow fan, adjusting the speed of the axial flow fan to a medium speed; When the temperature of the battery cell group is greater than the battery cell group threshold temperature, the temperature of the coolant is greater than the coolant threshold temperature, and the temperature difference of the coolant is greater than the coolant preset temperature difference, the speed of the axial flow fan is adjusted to high speed after starting the axial flow fan.

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