Energy storage system and control method therefor

Abstract

Provided are an energy storage system and a control method therefor. The energy storage system comprises: a battery (10), which is used for storing and releasing energy, and a heat management system (20), wherein the heat management system (20) comprises: a heat exchange loop (21) comprising a first heat exchanger (211) for exchanging heat with the battery (10), a heat exchange bypass (22) comprising a second heat exchanger (221) capable of natural cooling, and a bypass access mechanism (23) disposed in at least one of the heat exchange loop (21) and the heat exchange bypass (22), and by means of a switching operation of the bypass access mechanism (23), the heat exchange bypass (22) is connected to a heat exchange medium circulation of the heat exchange loop (21) or disconnected from the heat exchange medium circulation of the heat exchange bypass (22).

Description

Energy storage systems and their control methods

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to CN application No. 202411612379.1, filed on November 12, 2024, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] This invention relates to the field of energy storage technology, and in particular to an energy storage system and its control method. Background Technology

[0004] With increasing environmental pollution, the new energy industry is attracting more and more attention. Within this industry, battery technology is a crucial factor in its development. Rechargeable batteries, which can be reactivated after discharge, have broad application prospects in large-scale energy storage. Summary of the Invention

[0005] In one aspect of this disclosure, an energy storage system is provided, comprising: a battery for storing and releasing energy; and a thermal management system; wherein the thermal management system comprises: a heat exchange circuit including a first heat exchanger for exchanging heat with the battery; a heat exchange bypass including a second heat exchanger capable of natural cooling; and a bypass access mechanism disposed in at least one of the heat exchange circuit and the heat exchange bypass; wherein, by switching operation of the bypass access mechanism, the heat exchange bypass is connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit.

[0006] In this embodiment, the heat exchange circuit is equipped with a first heat exchanger capable of exchanging heat with the battery. Through the circulation of the heat exchange medium in the heat exchange circuit, heat exchange can be carried out between the first heat exchanger and the battery to meet the thermal management requirements of the battery. The heat exchange bypass is equipped with a second heat exchanger capable of natural cooling, which can effectively save external energy consumption. The heat exchange bypass can cooperate with the switching operation of the bypass access structure provided in at least one of the heat exchange circuit and the heat exchange bypass to realize the access or disconnection of the heat exchange medium circulation relative to the heat exchange circuit. This allows the thermal management system to establish different heat exchange medium circulation forms according to the actual situation, which can improve the adaptability of the energy storage system to thermal management and help meet the needs of improving thermal management efficiency and saving energy consumption.

[0007] In some embodiments, the bypass access mechanism includes a three-way liquid valve disposed in the heat exchange circuit and connected in series with the first heat exchanger; wherein, the first end of the heat exchange bypass is connected to the heat exchange circuit through the three-way liquid valve, and the first end of the heat exchange bypass is connected to or disconnected from the heat exchange circuit by switching the three-way liquid valve, and the second end of the heat exchange bypass is connected to the heat exchange circuit.

[0008] In this embodiment, the switching function of the three-way liquid valve in the heat exchange circuit can connect or disconnect the first end of the heat exchange bypass from the heat exchange circuit to meet the corresponding thermal management requirements.

[0009] In some embodiments, the three-way liquid valve is located downstream of the first heat exchanger along the heat exchange medium flow direction of the heat exchange circuit.

[0010] In this embodiment, the three-way liquid valve is positioned downstream of the first heat exchanger. This allows the flow diversion achieved by the three-way liquid valve after the battery heat exchange operation in the first heat exchanger, enabling more heat exchange medium to be used for heat exchange with the battery, thus improving heat exchange efficiency. The heat exchange medium after heat exchange in the first heat exchanger can be partially diverted to a heat exchange bypass via the three-way liquid valve for heating or natural cooling according to the battery's thermal management requirements.

[0011] In some embodiments, the three-way liquid valve is configured to adjust the flow distribution relationship between the heat exchange circuit and the heat exchange bypass when the heat exchange bypass is connected to the heat exchange circuit for the circulation of heat exchange medium.

[0012] In this embodiment, the heat exchange medium in the heat exchange circuit can be diverted at the position of the three-way liquid valve, with one part entering the heat exchange bypass and the other part continuing to operate within the heat exchange circuit. For a heat exchange circuit that exchanges heat with the compression refrigeration cycle circuit through an evaporator, when it is desired to improve the cooling effect of the battery and increase the amount of cold energy absorbed from the compression refrigeration cycle circuit, this increases the flow rate of the heat exchange medium continuing to operate within the heat exchange circuit, thereby increasing the flow rate of the heat exchange medium flowing through the internal heat exchange channels of the evaporator, thus absorbing more cold energy. When it is desired to meet the battery cooling needs while reducing energy consumption, the amount of heat exchange medium diverted to the heat exchange bypass can be increased to utilize the second heat exchanger in the heat exchange bypass for natural cooling, reducing the operating frequency or operating time of the compressor in the compression refrigeration cycle circuit, thereby saving energy consumption.

[0013] In some embodiments, the second heat exchanger includes a microchannel heat exchanger.

[0014] In this embodiment, the second heat exchanger is a microchannel heat exchanger, which can achieve higher heat exchange efficiency, improve the energy efficiency of the system, and occupy less space.

[0015] In some embodiments, the bypass access mechanism includes a control valve disposed in the heat exchange bypass and connected in series with the second heat exchanger, so as to open or close the heat exchange bypass by switching the control valve.

[0016] In this embodiment, by providing a control valve in the heat exchange bypass that can open and close the heat exchange bypass, the heat exchange bypass can be conveniently connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit as needed.

[0017] In some embodiments, the second heat exchanger flows downstream of the control valve along the heat exchange medium of the heat exchange bypass.

[0018] In this embodiment, the control valve can not only switch the heat exchange bypass on and off, but also directly control the flow rate entering the second heat exchanger upstream of the second heat exchanger, thereby matching the flow rate entering the second heat exchanger with the allowable flow rate of the second heat exchanger to improve heat exchange efficiency.

[0019] In some embodiments, the thermal management system further includes: a compression refrigeration cycle loop, the compression refrigeration cycle loop including an evaporator; wherein the evaporator further has an internal heat exchange channel, the internal heat exchange channel being connected in series in the heat exchange loop and exchanging heat with the compression refrigeration cycle loop through the evaporator.

[0020] In this embodiment, cooling is provided to the coolant in the heat exchange circuit through heat exchange between the compression refrigeration cycle circuit and the heat exchange circuit. This improves the thermal management efficiency of the heat exchange circuit and enhances the configuration flexibility for different thermal management needs. Furthermore, the compression refrigeration cycle circuit achieves high cooling efficiency, and by exchanging heat with the heat exchange circuit, it can effectively reduce the temperature of the coolant flowing in the heat exchange circuit, thereby increasing the cooling capacity of the circuit containing the heat exchange circuit.

[0021] In some embodiments, the heat exchange circuit further includes a pump connected in series with the first heat exchanger and the internal heat exchange channel, and located between the first heat exchanger and the internal heat exchange channel.

[0022] In this embodiment, the pump performs work on the heat exchange medium within the heat exchange circuit upon startup, enabling the medium to flow within the circuit. The pump can be positioned between the first heat exchanger and the internal heat exchange channel. Driven by the pump, the heat exchange medium flowing from the internal heat exchange channel absorbs the cooling energy from the compression refrigeration cycle and can then exchange heat with the battery within the first heat exchanger, improving the battery's cooling efficiency.

[0023] In some embodiments, the bypass access mechanism includes a three-way liquid valve disposed at a first position in the heat exchange circuit. The first position is located downstream of the first heat exchanger along the heat exchange medium flow of the heat exchange circuit. A first end of the heat exchange bypass is connected to the three-way liquid valve. The three-way liquid valve is configured to adjust the flow distribution relationship between the heat exchange circuit and the heat exchange bypass when the heat exchange bypass is connected to the heat exchange circuit and the heat exchange medium is circulating.

[0024] In this embodiment, the first position is located downstream of the first heat exchanger, so that after the heat exchange medium exchanges heat with the battery in the first heat exchanger, it can be diverted to the heat exchange bypass through a three-way liquid valve. The three-way liquid valve can distribute the flow between the heat exchange circuit and the heat exchange bypass, thereby adjusting the flow rate diverted to the heat exchange bypass and improving the adaptability of the thermal management system.

[0025] In some embodiments, the second end of the heat exchange bypass is connected to a second position in the heat exchange circuit, the second position being downstream of the first position along the heat exchange medium flow of the heat exchange circuit, and located on the side of the internal heat exchange channel away from the first position.

[0026] In this embodiment, the second position is set on the side of the internal heat exchange channel away from the first position. Through the diversion and flow distribution function of the three-way liquid valve, a portion of the heat exchange medium in the heat exchange circuit is diverted from one side of the internal heat exchange channel to the heat exchange bypass, and then flows back to the heat exchange return channel from the other side of the internal heat exchange channel, without passing through the internal heat exchange channel of the evaporator. This portion of the heat exchange medium can receive the cooling energy from the natural environment in the second heat exchanger, thereby helping to reduce energy consumption through natural cooling.

[0027] In some embodiments, the second end of the heat exchange bypass is connected to a second position in the heat exchange circuit, the second position being downstream of the first position along the heat exchange medium flow of the heat exchange circuit, and located on the side of the internal heat exchange channel adjacent to the first position.

[0028] In this embodiment, the second position is located on the side of the internal heat exchange channel adjacent to the first position. This allows the heat exchange medium flowing out from the heat exchange bypass to merge with the heat exchange medium flowing through the flow path from the first position to the second position before entering the internal heat exchange channel of the evaporator. This increases the amount of heat exchange medium flowing through the internal heat exchange channel of the evaporator, allowing more heat exchange medium to receive the cooling capacity provided by the compression refrigeration cycle.

[0029] In some embodiments, the compression refrigeration cycle loop further includes a condenser, and the thermal management system further includes a fan, which, when the fan is turned on to release air, causes airflow to act on the condenser and the second heat exchanger.

[0030] In this embodiment, by setting a fan to act on the condenser and the second heat exchanger, the heat exchange efficiency of the condenser and the second heat exchanger can be improved, thereby improving the overall heat exchange efficiency of the thermal management system.

[0031] In some embodiments, the thermal management system further includes: a heating component disposed in the heat exchange bypass and configured to heat the heat exchange medium flowing through the heat exchange bypass when the heating function is activated; and a fan configured to cause airflow to act on the second heat exchanger when the outlet air is activated.

[0032] In this embodiment, by using a heating component installed in the heat exchange bypass and a fan that can act on the second heat exchanger through airflow, different thermal management requirements of the battery can be met according to actual needs.

[0033] In some embodiments, the fan is configured to shut off the airflow when the heating component turns on the heating function, and turn on the airflow when the heating component turns off the heating function, while the heat exchange medium is circulating through the heat exchange bypass connected to the heat exchange circuit.

[0034] In this embodiment, when the battery requires heating, the heating element is activated to heat the heat exchange medium. At this time, the fan is turned off to reduce the heat dissipated from the heated heat exchange medium to the outside through the second heat exchanger, allowing more heat to be transferred to the battery and improving its heating effect. If the battery does not require heating but needs cooling, the heating element is turned off, and the fan is activated to allow the heat exchange medium flowing through the second heat exchanger to receive ambient cold with higher heat exchange efficiency, allowing more cold energy to be transferred to the battery and improving its cooling effect.

[0035] In some embodiments, the thermal management system further includes a heating component disposed in the heat exchange circuit and configured to heat the heat exchange medium flowing through the heat exchange circuit when the heating function is activated.

[0036] In this embodiment, by setting a heating component in the heat exchange circuit, the thermal management requirements under different ambient temperatures can be met as needed by turning the heating function of the heating component on and off.

[0037] In some embodiments, the thermal management system further includes: a compression refrigeration cycle loop, the compression refrigeration cycle loop including an evaporator; wherein the evaporator further has an internal heat exchange channel, the internal heat exchange channel being connected in series in the heat exchange loop and exchanging heat with the compression refrigeration cycle loop through the evaporator; a first end of the heat exchange bypass is connected to a first position in the heat exchange loop, the first position being downstream of the first heat exchanger along the heat exchange medium flow of the heat exchange loop; and a heating assembly is located between the first position and the internal heat exchange channel.

[0038] In this embodiment, the heat exchange medium flow along the heat exchange circuit at the first position is located downstream of the first heat exchanger. The flow rate of the heat exchange medium entering the heat exchange bypass and the heat exchange medium entering the internal heat exchange channel of the evaporator can be distributed by the heating component. This makes the flow rate in the heat exchange bypass conform to the allowable flow rate range of the second heat exchanger, reducing pressure drop and improving heat exchange efficiency.

[0039] In some embodiments, the heating assembly includes: a heater for turning the heating function on or off; and a flow control valve connected in parallel with the heater for controlling the flow rate of the heat exchange medium through the flow control valve.

[0040] In this embodiment, considering that the flow rate of the heat exchange medium entering the heat exchange bypass may differ from the allowable flow rate of the heater, which may create flow resistance at the heater location, the flow distribution can be controlled by using a flow control valve connected in parallel with the heater. This can reduce the risk of flow resistance forming in the heater, improve the circulation efficiency of the heat exchange medium, and enhance the energy efficiency of thermal management.

[0041] In some embodiments, the bypass access mechanism is configured to: switch to a state that disconnects the heat exchange bypass from the heat exchange medium circulation of the heat exchange circuit in response to an ambient temperature greater than or equal to a first ambient temperature threshold; and switch to a state that connects the heat exchange bypass to the heat exchange medium circulation of the heat exchange circuit in response to an ambient temperature less than or equal to a second ambient temperature threshold; wherein the first ambient temperature threshold is greater than the second ambient temperature threshold.

[0042] In this embodiment, the state of the bypass access mechanism is switched according to the comparison result of the ambient temperature relative to the threshold, so that the heat exchange bypass can be connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit. This can effectively meet the different thermal management requirements under different ambient temperatures and save energy.

[0043] In one aspect of this disclosure, a control method for the aforementioned energy storage system is provided, comprising: switching the bypass access mechanism to allow the heat exchange bypass to either connect to or disconnect from the heat exchange medium circulation of the heat exchange circuit.

[0044] In this embodiment, by switching the bypass access mechanism, the heat exchange bypass equipped with a second heat exchanger capable of natural cooling can be connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit. This allows the thermal management system to establish different heat exchange medium circulation forms according to actual conditions, which can improve the adaptability of the energy storage system to thermal management and help meet the needs of improving thermal management efficiency and saving energy consumption.

[0045] In some embodiments, the control method further includes: adjusting the flow distribution relationship between the heat exchange circuit and the heat exchange bypass through the bypass access mechanism while the heat exchange medium is circulating through the heat exchange bypass access mechanism.

[0046] In this embodiment, the flow distribution relationship between the heat exchange circuit and the heat exchange bypass can be adjusted through the bypass access mechanism according to the actual thermal management requirements and the allowable flow of the devices in the thermal management system. This is beneficial to improving the heat exchange effect of the system and reducing the system energy consumption.

[0047] In some embodiments, the step of connecting or disconnecting the heat exchange bypass from the heat exchange medium circulation of the heat exchange circuit through the switching operation of the bypass access mechanism includes: disconnecting the heat exchange bypass from the heat exchange medium circulation of the heat exchange circuit through the switching operation of the bypass access mechanism in response to an ambient temperature greater than or equal to a first ambient temperature threshold; and connecting the heat exchange bypass to the heat exchange medium circulation of the heat exchange circuit through the switching operation of the bypass access mechanism in response to an ambient temperature less than or equal to a second ambient temperature threshold; wherein the first ambient temperature threshold is greater than the second ambient temperature threshold.

[0048] In this embodiment, the state of the bypass access mechanism is switched according to the comparison result of the ambient temperature relative to the threshold, so that the heat exchange bypass can be connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit. This can effectively meet the different thermal management requirements under different ambient temperatures and save energy. Attached Figure Description

[0049] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the specification, serve to explain the principles of this disclosure.

[0050] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein:

[0051] Figure 1 is a schematic diagram of the structure of some embodiments of the energy storage system according to the present disclosure;

[0052] Figure 2 is a schematic diagram of the thermal management system according to the first embodiment of the energy storage system of the present disclosure;

[0053] Figure 3A is a schematic diagram of the thermal management system according to a second embodiment of the energy storage system of the present disclosure;

[0054] Figures 3B and 3C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 3A.

[0055] Figure 4 is a schematic diagram of the thermal management system according to a third embodiment of the energy storage system of the present disclosure;

[0056] Figure 5A is a schematic diagram of the thermal management system according to the fourth embodiment of the energy storage system of the present disclosure;

[0057] Figures 5B and 5C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 5A.

[0058] Figure 6A is a schematic diagram of the thermal management system according to the fifth embodiment of the energy storage system of the present disclosure;

[0059] Figures 6B and 6C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 6A.

[0060] Figure 7A is a schematic diagram of the thermal management system according to the sixth embodiment of the energy storage system of the present disclosure;

[0061] Figures 7B and 7C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 7A.

[0062] It should be understood that the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Furthermore, the same or similar reference numerals denote the same or similar components.

[0063] Explanation of reference numerals in the attached diagram: 10-Battery; 20-Thermal management system; 21-Heat exchange circuit; 211-First heat exchanger; 212-Pump; 213-Expansion tank; 22-Heat exchange bypass; 221-Second heat exchanger; 2211-Microchannel heat exchanger; 23-Bypass access mechanism; 231-Three-way liquid valve; 232-Control valve; 24-Compression refrigeration cycle circuit; 241-Compressor; 242-Condenser; 243-Throttling device; 244-Evaporator; 2441-Internal heat exchange channel; 245-Gas-liquid separator; 25-Heating component; 251-Heater; 252-Flow control valve; 26-Fan; P1-First position; P2-Second position. Detailed Implementation

[0064] The embodiments of the technical solutions disclosed herein will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solutions disclosed herein and are therefore intended to limit the scope of protection of this disclosure.

[0065] Unless otherwise defined, all technical and scientific terms used in this disclosure have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains; the terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings of this disclosure are intended to cover non-exclusive inclusion.

[0066] In the description of the embodiments of this disclosure, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. In the description of the embodiments of this disclosure, "a plurality of" means two or more, unless otherwise explicitly defined.

[0067] In this disclosure, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this disclosure. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this disclosure can be combined with other embodiments.

[0068] In the description of the embodiments of this disclosure, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, if the character " / " appears in this disclosure, it generally indicates that the preceding and following related objects have an "or" relationship.

[0069] In the description of the embodiments of this disclosure, the term "multiple" refers to two or more (including two), similarly, "multiple groups" refers to two or more (including two groups), and "multiple pieces" refers to two or more (including two pieces).

[0070] In the description of embodiments of this disclosure, the term "at least one" refers to one or more (including two), similarly, "at least one group" refers to one or more (including two) groups, and "at least one piece" refers to one or more (including two) pieces. In the description of embodiments of this disclosure, the term "at least part" refers to part or all of them.

[0071] Unless otherwise specified, in the description of the embodiments of this disclosure, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure.

[0072] In the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0073] In this embodiment of the disclosure, the energy storage system may include an energy storage device and an energy storage converter. The energy storage device may include one or more batteries for storing electrical energy, and its structure may be an energy storage container, an energy storage cabinet, etc. The batteries in the energy storage device can be used to store surplus electrical energy during off-peak hours in the power system to supplement electricity consumption during peak hours.

[0074] Energy storage converters control the charging and discharging processes of batteries, converting AC to DC power, and can directly supply power to AC loads even without a power grid. An energy storage converter may include a DC / AC bidirectional converter and a controller. The controller receives control commands from the backend via communication and controls the converter to charge or discharge the battery according to the sign and magnitude of the power command, thereby regulating the active and reactive power of the power grid. The controller can communicate with the battery's battery management system (BMS) via a bus interface to obtain battery status information, enabling protective charging and discharging of the battery and improving battery operation safety.

[0075] In this embodiment of the disclosure, a battery refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. A battery cell is the smallest unit constituting a battery. A battery cell includes electrode components capable of undergoing electrochemical reactions. A battery cell can be a rechargeable battery, meaning a battery cell that can be recharged after discharge to activate its active materials and continue to be used.

[0076] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments disclosed herein are not limited to this.

[0077] In some embodiments, the battery may include a housing and individual battery cells, with the individual battery cells housed within the housing. The housing may be made of metal, non-metal, or a combination of materials. Multiple individual battery cells may be arranged along at least one of the length and width directions of the housing. At least one row or column of battery cells may be provided as needed. Alternatively, one or more layers of battery cells may be provided along the height direction of the battery, as required.

[0078] The individual battery cells are electrically connected, such as in series, parallel, or a combination thereof, to achieve the desired electrical performance parameters. A combination thereof refers to multiple battery cells being connected in both series and parallel configurations. Adjacent battery cells can be electrically connected via busbars. Multiple battery cells can be arranged in rows; one or more rows of battery cells can be installed within the enclosure as needed. The enclosure can be made of metal, non-metal, or a mixture of materials.

[0079] In some embodiments, the battery may include a housing and a battery module, the housing providing a space for the battery module, which is installed inside the housing. Multiple battery cells may first be connected in series, parallel, or in a mixed configuration to form a battery module, and then the multiple battery modules may be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed inside the housing.

[0080] In some embodiments, the battery cell includes an electrode assembly, a housing, and an end cap. The housing has a receiving cavity for receiving the electrode assembly and an open end communicating with the receiving cavity. The end cap closes to the open end.

[0081] The electrode assembly may include a first electrode and a second electrode with opposite polarities, and a separator disposed between the first electrode and the second electrode. In some embodiments, the first electrode is a positive electrode and the second electrode is a negative electrode. In other embodiments, the first electrode is a negative electrode and the second electrode is a positive electrode. During the charging and discharging of a single battery cell, active ions (e.g., lithium ions) repeatedly insert and extract between the positive and negative electrode. The separator, disposed between the positive and negative electrode, serves to prevent short circuits between the positive and negative electrodes while allowing active ions to pass through.

[0082] In some embodiments, the positive electrode may include a positive current collector substrate and a positive active material layer disposed on at least one surface of the positive current collector substrate.

[0083] As an example, the positive electrode current collector substrate has two surfaces opposite each other in its own thickness direction, and the positive electrode active material layer is disposed on either or both of the two opposite surfaces of the positive electrode current collector substrate.

[0084] As an example, the positive electrode current collector substrate can be a metal foil or a composite current collector. For example, as a metal foil, silver-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc., can be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by applying a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) onto a polymer material base material (such as a polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc. base material).

[0085] As an example, the positive electrode active material layer may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this disclosure is not limited to these materials, and other conventional materials that can be used as positive electrode active material layers in batteries may also be used. These positive electrode active material layers may be used alone or in combination of two or more. Examples of lithium phosphate include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxides include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05At least one of O2 and its modified compounds.

[0086] In some embodiments, the negative electrode sheet may include a negative current collector substrate.

[0087] As an example, the negative electrode current collector substrate can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be silver-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. Foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by applying a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) onto a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0088] In some embodiments, the negative electrode sheet may include a negative electrode current collector substrate and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector substrate.

[0089] As an example, the negative electrode current collector substrate has two surfaces opposite each other in its own thickness direction, and the negative electrode active material layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector substrate.

[0090] As an example, the negative electrode active material layer may employ a type of negative electrode active material layer known in the art for use in battery cells. As an example, the negative electrode active material layer may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this disclosure is not limited to these materials, and other conventional materials that can be used as negative electrode active material layers in batteries may also be used. These negative electrode active material layers may be used alone or in combination of two or more.

[0091] In some embodiments, the positive electrode current collector substrate can be made of aluminum, and the negative electrode current collector substrate can be made of copper.

[0092] In some embodiments, the separator is a separator membrane. This disclosure does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0093] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a separate component located between the positive and negative electrode plates, or it can be located between the positive and negative electrode plates while being attached to the surface of the positive electrode plate and / or the surface of the negative electrode plate.

[0094] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrode plates, serving both to transport ions and to isolate the positive and negative electrodes.

[0095] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This disclosure does not impose specific limitations on the type of electrolyte, which can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0096] As an example, liquid electrolytes include electrolyte salts and solvents.

[0097] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0098] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0099] As an example, gel electrolytes include a polymer-based backbone network combined with an ionic liquid—a lithium salt.

[0100] As an example, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0101] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0102] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0103] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0104] In some embodiments, the electrode assembly includes a main body. The main body can be a wound structure formed by winding a positive electrode, a negative electrode, and a separator, or a stacked structure formed by overlapping positive electrode, negative electrode, and a separator. One or more positive and negative electrode sheets can be provided respectively. As an example, multiple positive electrode sheets and multiple negative electrode sheets are alternately arranged along the electrode thickness direction.

[0105] In some embodiments, the main body may be cylindrical, flat, or polygonal. The ends of the main body may be provided with a first tab and a second tab. The first tab can be formed by cutting or trimming the current collector substrate of the first electrode, or it can be welded to the side of the current collector substrate of the first electrode. The second tab can be formed by cutting or trimming the current collector substrate of the second electrode, or it can be welded to the side of the current collector substrate of the second electrode.

[0106] In an embodiment where the first electrode is a positive electrode and the second electrode is a negative electrode, the first electrode includes a positive electrode tab serving as a first electrode tab, and the second electrode includes a negative electrode tab serving as a second electrode tab. In an embodiment where the first electrode is a negative electrode and the second electrode is a positive electrode, the first electrode includes a negative electrode tab serving as a first electrode tab, and the second electrode includes a positive electrode tab serving as a second electrode tab.

[0107] The housing is used to encapsulate electrode components and electrolytes. The housing can be made of steel, aluminum, or composite metals (such as a copper-aluminum composite housing).

[0108] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries.

[0109] Pressure relief components may be provided on the end cap or housing. A pressure relief component is an element or part that is activated to release internal pressure or temperature when the internal pressure or temperature of a battery cell reaches a predetermined threshold. This threshold design varies depending on design requirements. The threshold may depend on one or more materials of the positive electrode, negative electrode, electrolyte, and separator in the battery cell. The pressure relief section can take the form of an explosion-proof valve, gas valve, pressure relief valve, or safety valve, and can specifically employ pressure-sensitive or temperature-sensitive elements or structures. That is, when the internal pressure or temperature of the battery cell reaches the predetermined threshold, the pressure relief section actuates or a weak structure within the pressure relief section is damaged, thereby forming an opening or channel for the release of internal pressure or temperature.

[0110] In the event of thermal runaway or other unforeseen circumstances in the electrode assembly, the resulting high-temperature, high-pressure gas enters the pressure relief chamber. This gas may also contain active materials. When the pressure within the pressure relief chamber exceeds the design threshold, the pressure relief section releases internal pressure, expelling emissions from the battery cells. These emissions from the battery cells include, but are not limited to: electrolyte, dissolved or fragmented positive and negative electrode plates, fragments of the separator, high-temperature, high-pressure gases generated during the reaction (such as CH4, CO, and other combustible gases), flames, etc.

[0111] In some related technologies, to meet the thermal management requirements of batteries in energy storage systems, the batteries are heated or cooled by cold plates in the liquid cooling circulation loop, and a liquid cooling bypass is connected in parallel at a certain location in the liquid cooling circulation loop to further dissipate heat from the diverted coolant.

[0112] Research has found that under certain environmental conditions (such as high ambient temperature), the efficiency of cooling the coolant diverted to the liquid-cooled bypass through air cooling is relatively low, which affects the cooling of the battery to some extent and reduces the overall cooling efficiency of the energy storage system. Therefore, its adaptability in thermal management still needs to be improved.

[0113] In view of this, embodiments of the present disclosure provide an energy storage system and a control method thereof, which can improve the adaptability of the energy storage system to thermal management.

[0114] In one aspect of this disclosure, an energy storage system is provided, comprising:

[0115] Batteries are used to store and release energy; and

[0116] Thermal management system;

[0117] The thermal management system includes:

[0118] A heat exchange circuit includes a first heat exchanger for exchanging heat with the battery;

[0119] Heat exchange bypass, including a second heat exchanger capable of achieving natural cooling; and

[0120] A bypass access mechanism is provided in at least one of the heat exchange circuit and the heat exchange bypass;

[0121] The bypass access mechanism switches the heat exchange bypass to either connect to or disconnect from the heat exchange medium circulation in the heat exchange circuit.

[0122] In this embodiment, the heat exchange circuit is equipped with a first heat exchanger capable of exchanging heat with the battery. Through the circulation of the heat exchange medium in the heat exchange circuit, heat exchange can be carried out between the first heat exchanger and the battery to meet the thermal management requirements of the battery. The heat exchange bypass is equipped with a second heat exchanger capable of natural cooling, which can effectively save external energy consumption. The heat exchange bypass can cooperate with the switching operation of the bypass access structure provided in at least one of the heat exchange circuit and the heat exchange bypass to realize the access or disconnection of the heat exchange medium circulation relative to the heat exchange circuit. This allows the thermal management system to establish different heat exchange medium circulation forms according to the actual situation, which can improve the adaptability of the energy storage system to thermal management and help meet the needs of improving thermal management efficiency and saving energy consumption.

[0123] Figure 1 is a structural schematic diagram of some embodiments of the energy storage system according to the present disclosure. Figure 2 is a structural schematic diagram of the thermal management system according to a first embodiment of the energy storage system according to the present disclosure. Referring to Figures 1 and 2, an embodiment of the present disclosure provides an energy storage system, including: a battery 10 and a thermal management system 20. The battery 10 is used to store and release energy. The thermal management system 20 includes: a heat exchange circuit 21, a heat exchange bypass 22, and a bypass access mechanism 23. The heat exchange circuit 21 includes a first heat exchanger 211 for heat exchange with the battery 10. The heat exchange bypass 22 includes a second heat exchanger 221 capable of natural cooling. The bypass access mechanism 23 is disposed in at least one of the heat exchange circuit 21 and the heat exchange bypass 22; wherein, by switching operation of the bypass access mechanism 23, the heat exchange bypass 22 is connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit 21.

[0124] The thermal management system 20 can be used to perform thermal management on components in an energy storage system, including the battery 10, such as cooling or heating the battery 10. The thermal management system 20 can be connected to the battery 10 to achieve thermal management of the battery 10. The heat exchange medium operating in the heat exchange circuit 21 and the heat exchange bypass 22 can be a liquid, such as water, aqueous coolant, or anhydrous coolant, but is not limited to liquids; it can also be a gas, a solid-liquid mixture, or a gas-liquid mixture.

[0125] The first heat exchanger 211 can transfer heat to the battery 10 by means of, but not limited to, thermal conduction. For example, the first heat exchanger 211 may include a cooling plate in contact with the battery 10. The cooling plate may be independent of the battery 10 or may be part of the battery 10, for example, disposed at the bottom of the battery housing or between individual battery cells in the battery module.

[0126] The second heat exchanger 221 can achieve natural cooling. It can utilize natural cold sources such as air and water to exchange heat with the heat exchange medium flowing through the second heat exchanger 221, which can significantly reduce energy consumption in this process. The second heat exchanger 221 may include a microchannel heat exchanger or a plate heat exchanger, etc.

[0127] The bypass access mechanism 23 can be disposed in the heat exchange circuit 21, the heat exchange bypass 22, or both. This also includes the case where the bypass access mechanism 23 is disposed at the connection point between the heat exchange circuit 21 and the heat exchange bypass 22.

[0128] The bypass access mechanism 23 can perform switching operations based on received control commands (e.g., receiving control commands from the processor), or in response to external operations (e.g., operator manual triggering of a mode button). Through the switching operation of the bypass access mechanism 23, it is possible to switch between a mode where the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21 and a mode where the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21.

[0129] When the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21, part of the heat exchange medium in the heat exchange circuit 21 is diverted to the heat exchange bypass 22, and the second heat exchanger 221 is used to obtain the cooling capacity from the natural environment before returning to the heat exchange circuit 21, thereby effectively saving energy consumption.

[0130] When the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21, the heat exchange medium in the heat exchange circuit 21 is not diverted to the heat exchange bypass 22, so that it can circulate in the heat exchange circuit 21 at a larger flow rate, thereby improving the heat exchange efficiency in the heat exchange circuit 21.

[0131] In this embodiment, the heat exchange circuit 21 is provided with a first heat exchanger 211 capable of exchanging heat with the battery 10. Through the circulation of the heat exchange medium in the heat exchange circuit 21, heat exchange can be performed between the first heat exchanger 211 and the battery 10 to meet the thermal management requirements of the battery 10. The heat exchange bypass 22 is provided with a second heat exchanger 221 capable of achieving natural cooling, which can effectively save external energy consumption. The heat exchange bypass 22 can cooperate with the switching operation of the bypass access mechanism 23 provided in at least one of the heat exchange circuit 21 and the heat exchange bypass 22 to realize the access or disconnection of the heat exchange medium circulation relative to the heat exchange circuit 21. This allows the thermal management system 20 to establish different heat exchange medium circulation forms according to the actual situation, which can improve the adaptability of the energy storage system to thermal management and help meet the needs of improving thermal management efficiency and saving energy consumption.

[0132] Referring to FIG2, in some embodiments, the second heat exchanger 221 includes a microchannel heat exchanger 2211.

[0133] The microchannel heat exchanger 2211 typically includes a flat tube with multiple internal microchannels and a manifold connected to the flat tube. The equivalent diameter of the microchannels in the flat tube can be 10-1000 μm. A baffle may be installed inside the manifold to divide the heat exchanger's flow channels into multiple paths. The allowable flow rate of the microchannel heat exchanger 2211 may be less than the flow rate of the heat exchange loop 21. Directly receiving the flow rate from the heat exchange loop 21 could cause significant pressure loss. However, through the flow distribution function of the bypass access mechanism 23, the flow rate operating in the heat exchange bypass 22 can be matched with the allowable flow rate of the microchannel heat exchanger 2211, thereby reducing pressure loss and improving heat exchange efficiency.

[0134] In this embodiment, the second heat exchanger 221 adopts a microchannel heat exchanger 2211, which can achieve higher heat exchange efficiency, improve the energy efficiency of the system, and occupy less space.

[0135] Figure 3A is a schematic diagram of the thermal management system according to a second embodiment of the energy storage system of this disclosure. Referring to Figure 3A, in some embodiments, the thermal management system 20 further includes a compression refrigeration cycle loop 24. The compression refrigeration cycle loop 24 includes an evaporator 244; wherein, the evaporator 244 further has an internal heat exchange channel 2441, which is connected in series with the heat exchange loop 21 and exchanges heat with the compression refrigeration cycle loop 24 through the evaporator 244.

[0136] The compression refrigeration cycle loop 24 circulates the refrigerant fluid, achieving heat transfer through the condensation and evaporation of the refrigerant. The refrigerant may include, but is not limited to, water, ammonia, carbon dioxide, and halogenated hydrocarbon refrigerants. The refrigerant in the compression refrigeration cycle loop 24 operates independently of the heat exchange medium in the heat exchange loop 21, achieving heat transfer through heat exchange. In different modes of the thermal management system 20, the compression refrigeration cycle loop 24 can operate to enhance the cooling capacity of the thermal management system 20, or it can remain inactive to save energy consumption.

[0137] The heat exchange loop 21 is connected in series with the internal heat exchange channel 2441 of the evaporator 244. The heat exchange medium in the heat exchange loop 21 flows through the internal heat exchange channel 2441, thus the internal heat exchange channel 2441 is equivalent to a part of the heat exchange loop 21. The heat exchange medium flowing through the internal heat exchange channel 2441 can exchange heat with the refrigerant flowing through the evaporator 244, allowing the heat exchange loop 21 to receive cooling energy from the compression refrigeration cycle loop 24, thereby cooling the flowing heat exchange medium. In Figure 3A, the internal heat exchange channel 2441 and the internal piping of the compression refrigeration cycle loop 24 through the evaporator 244 are shown by dashed lines drawn inside the evaporator 244. The evaporator 244 can be a plate heat exchanger evaporator or other types of evaporators, such as a shell-and-tube evaporator.

[0138] In this embodiment, the heat exchange between the compression refrigeration cycle 24 and the heat exchange circuit 21 provides cooling to the coolant in the heat exchange circuit 21, which helps improve the thermal management efficiency of the heat exchange circuit 21 and increases the configuration flexibility for different thermal management needs. Furthermore, the compression refrigeration cycle 24 can achieve high cooling efficiency, and by exchanging heat with the heat exchange circuit 21, it can effectively reduce the temperature of the coolant flowing in the heat exchange circuit 21, thereby improving the cooling capacity of the circuit containing the heat exchange circuit 21.

[0139] Referring to FIG3A, in some embodiments, the heat exchange circuit 21 further includes a pump 212, which is connected in series with the first heat exchanger 211 and the internal heat exchange channel 2441 and is located between the first heat exchanger 211 and the internal heat exchange channel 2441.

[0140] In this embodiment, when the pump 212 starts, it can perform work on the heat exchange medium in the heat exchange circuit 21, allowing the heat exchange medium to flow within the heat exchange circuit 21. The pump 212 can be located between the first heat exchanger 211 and the internal heat exchange channel 2441. Driven by the pump 212, the heat exchange medium flowing out from the internal heat exchange channel 2441 absorbs the cooling energy of the compression refrigeration cycle circuit 24 and can exchange heat with the battery 10 within the first heat exchanger 211, thereby improving the cooling efficiency of the battery 10.

[0141] Referring to Figure 3A, in some embodiments, the bypass access mechanism 23 includes a three-way liquid valve 231, which is disposed at a first position P1 of the heat exchange circuit 21. The first position P1 is located downstream of the first heat exchanger 211 along the heat exchange medium flow of the heat exchange circuit 21. The first end of the heat exchange bypass 22 is connected to the three-way liquid valve 231. The three-way liquid valve 231 is configured to adjust the flow distribution relationship between the heat exchange circuit 21 and the heat exchange bypass 22 when the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21.

[0142] In this embodiment, the first position P1 is located downstream of the first heat exchanger 211, so that after the heat exchange medium exchanges heat with the battery 10 in the first heat exchanger 211, it can be diverted to the heat exchange bypass 22 through the three-way liquid valve 231. The three-way liquid valve 231 can distribute the flow between the heat exchange circuit 21 and the heat exchange bypass 22, realize the flow adjustment of the diverted flow to the heat exchange bypass 22, thereby improving the adaptability of the thermal management system 20.

[0143] Referring to Figure 3A, in some embodiments, the second end of the heat exchange bypass 22 is connected to the second position P2 of the heat exchange circuit 21. The second position P2 is downstream of the first position P1 along the heat exchange medium flow direction of the heat exchange circuit 21 and is located on the side of the internal heat exchange channel 2441 away from the first position P1.

[0144] In this embodiment, the second position P2 is set on the side of the internal heat exchange channel 2441 away from the first position P1. Through the diversion and flow distribution function of the three-way liquid valve 231, a portion of the heat exchange medium in the heat exchange circuit 21 is diverted from one side of the internal heat exchange channel 2441 to the heat exchange bypass 22, and then flows back to the heat exchange circuit 21 from the other side of the internal heat exchange channel 2441, without passing through the internal heat exchange channel 2441 of the evaporator 244. This portion of the heat exchange medium can receive the cooling energy from the natural environment in the second heat exchanger 221, thereby helping to reduce energy consumption through natural cooling.

[0145] Referring to Figure 3A, in some embodiments, the compression refrigeration cycle loop 24 further includes a condenser 242, and the thermal management system 20 further includes a fan 26, which, when the fan 26 is turned on, causes airflow to act on the condenser 242 and the second heat exchanger 221.

[0146] In Figure 3A, the compression refrigeration cycle loop 24 also includes a compressor 241, a condenser 242, a throttling device 243, and a gas-liquid separator 245. The compressor 241 can perform start-up and shutdown operations according to the processor instructions, and can also adjust its operating frequency or operating time. The compressor 241 can compress the intake low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant.

[0147] The condenser 242 cools and at least partially converts the high-temperature, high-pressure gaseous refrigerant output from the compressor 241 into a liquid state by releasing heat. The throttling device 243 may include a capillary tube, a thermostatic expansion valve, or an electronic expansion valve, which cools and depressurizes the refrigerant output from the condenser 242 by throttling. The evaporator 244 heats the refrigerant passing through the throttling device 243 by absorbing heat, at least partially converting it into a gaseous state. The gas-liquid separator 245 separates the refrigerant output from the evaporator 244 into a gaseous state and inputs the separated low-temperature, low-pressure gaseous refrigerant into the compressor 241.

[0148] Additionally, in Figure 3A, the thermal management system 20 may also include a fan 26, which can provide air cooling for the condenser 242 to improve its efficiency. The fan 26 may include axial, centrifugal, or mixed-flow fans. The fan 26 can also guide airflow in the environment to exchange heat with the second heat exchanger 221, improving heat exchange efficiency. This reduces the number of fans 26 required, thus lowering costs and energy consumption.

[0149] In this embodiment, by setting a fan 26 to act on the condenser 242 and the second heat exchanger 221, the heat exchange efficiency of the condenser 242 and the second heat exchanger 221 can be improved, thereby improving the overall heat exchange efficiency of the thermal management system.

[0150] Referring to Figure 3A, in some embodiments, the thermal management system 20 further includes a heating component 25 and a fan 26. The heating component 25 is disposed in the heat exchange bypass 22 and configured to heat the heat exchange medium flowing through the heat exchange bypass 22 when the heating function is activated. The fan 26 is configured to cause airflow to act on the second heat exchanger 221 when the outlet air is activated.

[0151] The heating component 25, installed in the heat exchange bypass 22, heats the heat exchange medium flowing through it when its heating function is activated. When the battery 10 requires heating, the bypass access mechanism 23 switches the heat exchange medium from the bypass 22 to the heat exchange circuit 21, and then activates the heating component 25 to heat the heat exchange medium flowing through the bypass 22 before returning to the heat exchange circuit 21 for heat exchange with the battery 10 in the first heat exchanger 211, thus improving the battery 10's performance. When the battery 10 does not require heating, the heating component 25 can be deactivated.

[0152] By placing the heating component 25 in the heat exchange bypass 22, the risk of the heating component 25 forming flow resistance in the heat exchange circuit 21 can be eliminated. In addition, the risk of surface condensation caused by placing the heating component 25 in the heat exchange circuit 21 at a relatively low temperature under high ambient temperature is also eliminated.

[0153] When the fan 26 is turned on, it directs airflow onto the second heat exchanger 221, thereby improving the heat exchange efficiency of the second heat exchanger 221. When the heat exchange bypass 22 connects to the heat exchange circuit 21 for heat exchange medium circulation, turning on the fan 26 enhances natural cooling, saving energy consumption. Conversely, when the fan 26 is turned off, the heat exchange efficiency of the second heat exchanger 221 can be reduced as needed.

[0154] In this embodiment, by using the heating component 25 provided in the heat exchange bypass 22 and the fan 26 that can act on the second heat exchanger 221 of the heat exchange bypass 22 through airflow, different thermal management requirements of the battery can be met according to actual needs.

[0155] In some embodiments, the fan 26 is configured to shut off the airflow when the heating component 25 turns on the heating function, and turn on the airflow when the heating component 25 turns off the heating function, while the heat exchange bypass 22 is connected to the heat exchange circuit 21 for heat exchange medium circulation.

[0156] In this embodiment, when the battery 10 requires heating, the heating component 25 is turned on to heat the heat exchange medium. At this time, the fan 26 is turned off to reduce the heat dissipated to the outside by the heated heat exchange medium through the second heat exchanger 221, allowing more heat to be transferred to the battery and improving the battery's heating effect. If the battery 10 does not require heating but needs cooling, the heating component 25 is turned off and the fan is turned on to allow the heat exchange medium flowing through the second heat exchanger 221 to receive the cold air from the environment with higher heat exchange efficiency, allowing more cold air to be transferred to the battery and improving the battery's cooling effect.

[0157] Referring to Figure 3A, in some embodiments, the heating assembly 25 includes a heater 251 and a flow control valve 252. The heater 251 is used to turn the heating function on or off. The flow control valve 252 is connected in parallel with the heater 251 and is used to control the flow rate of the heat exchange medium through the flow control valve 252.

[0158] Heater 251 can be an electric heater, a steam heater, or any other available heater. For example, heater 251 can be a safe and efficient positive temperature coefficient (PTC) heater. Flow control valve 252 can change the flow rate of the fluid flowing through it by adjusting the valve opening, thereby changing the velocity or pressure of the fluid flowing through the valve.

[0159] In this embodiment, considering that the flow rate of the heat exchange medium entering the heat exchange bypass 22 may differ from the allowable flow rate of the heater 251, which may create flow resistance at the location of the heater 251, the flow distribution can be controlled by using a flow control valve 252 connected in parallel with the heater 251. This can reduce the risk of flow resistance forming in the heater 251, improve the circulation efficiency of the heat exchange medium, and improve the energy efficiency of thermal management.

[0160] Referring to Figure 3A, in some embodiments, the bypass access mechanism 23 includes a three-way liquid valve 231, which is disposed in the heat exchange circuit 21 and connected in series with the first heat exchanger 211; wherein, the first end of the heat exchange bypass 22 is connected to the heat exchange circuit 21 through the three-way liquid valve 231, and the first end of the heat exchange bypass 22 is connected to or disconnected from the heat exchange circuit 21 by switching the three-way liquid valve 231, and the second end of the heat exchange bypass 22 is connected to the heat exchange circuit 21.

[0161] A three-way liquid valve 231 is installed in the heat exchange circuit 21 and can control the connection or disconnection between the first end of the heat exchange bypass 22 and the heat exchange circuit 21. When the first end of the heat exchange bypass 22 is connected to the heat exchange circuit 21, at least a portion of the heat exchange medium in the heat exchange circuit 21 can enter the heat exchange bypass 22 from the first end under the drive of the pump 212, flow through the heat exchange bypass 22, and flow back to the heat exchange circuit 21 from the second end of the heat exchange bypass 22. When the first end of the heat exchange bypass 22 is disconnected from the heat exchange circuit 21, the heat exchange medium in the heat exchange circuit 21 will not enter the heat exchange bypass 22 from the first end.

[0162] The three-way liquid valve 231 may have three connectors. The first connector connects to the first end of the heat exchange bypass 22, the second connector connects to the flow path of the heat exchange circuit 21 upstream of the three-way liquid valve 231, and the third connector connects to the flow path of the heat exchange circuit 21 downstream of the three-way liquid valve 231. In Figure 3A, the second connector corresponds to the inlet of the heat exchange medium, and the first and third connectors correspond to the outlet of the heat exchange medium. By adjusting the valve opening of the three-way liquid valve 231, the flow rate from the second connector to the first connector and the flow rate from the second connector to the third connector can be changed.

[0163] In this embodiment, by using the switching function of the three-way liquid valve 231 in the heat exchange circuit 21, the first end of the heat exchange bypass 22 can be connected to or disconnected from the heat exchange circuit 21 to meet the corresponding thermal management requirements.

[0164] Referring to Figure 3A, in some embodiments, the three-way liquid valve 231 is located downstream of the first heat exchanger 211 along the heat exchange medium flow direction of the heat exchange circuit 21.

[0165] In this embodiment, the three-way liquid valve 231 is positioned downstream of the first heat exchanger 211. This allows the flow diversion achieved by the three-way liquid valve 231 after the first heat exchanger 211 has performed its heat exchange operation on the battery 10. This enables more heat exchange medium to be used for heat exchange with the battery 10, which is beneficial for improving heat exchange efficiency. The heat exchange medium after heat exchange in the first heat exchanger 211 can be partially diverted to the heat exchange bypass 22 through the three-way liquid valve 231 for heating or natural cooling according to the battery's thermal management requirements.

[0166] In some embodiments, the three-way liquid valve 231 is configured to adjust the flow distribution relationship between the heat exchange circuit 21 and the heat exchange bypass 22 when the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21.

[0167] In this embodiment, the heat exchange medium in the heat exchange circuit 21 can be diverted at the position of the three-way liquid valve 231, with one part entering the heat exchange bypass 22 and the other part continuing to operate within the heat exchange circuit 21. For the heat exchange circuit 21, which exchanges heat with the compression refrigeration cycle circuit 24 through the evaporator, when it is desired to improve the cooling effect of the battery 10, the amount of cold energy absorbed from the compression refrigeration cycle circuit 24 can be increased. This increases the flow rate of the heat exchange medium continuing to operate within the heat exchange circuit 21, thereby increasing the flow rate of the heat exchange medium flowing through the internal heat exchange channel 2441 of the evaporator 244, thus absorbing more cold energy. When it is desired to meet the cooling needs of the battery 10 while reducing energy consumption, the amount of heat exchange medium diverted to the heat exchange bypass 22 can be increased so that natural cooling can be achieved using the second heat exchanger 221 in the heat exchange bypass 22, reducing the operating frequency or operating time of the compressor in the compression refrigeration cycle circuit 24, thereby saving energy consumption.

[0168] Figures 3B and 3C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 3A. Figure 3B shows the pump 212 and compressor 241 in operation in bold, and also shows the compression refrigeration loop 24 for refrigerant circulation and the heat exchange loop 21 for heat exchange medium circulation in bold. Figure 3C shows the pump 212 in operation in bold, and also shows the heat exchange loop 21 and heat exchange bypass 22 for heat exchange medium circulation in bold.

[0169] Referring to Figures 3B and 3C, in some embodiments, the bypass access mechanism 23 is configured to: switch to a state where the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21 in response to an ambient temperature greater than or equal to a first ambient temperature threshold; and switch to a state where the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21 in response to an ambient temperature less than or equal to a second ambient temperature threshold; wherein the first ambient temperature threshold is greater than the second ambient temperature threshold.

[0170] Ambient temperature refers to the temperature of the environment in which the thermal management system 20 is located, which can be obtained through temperature detection instruments such as thermometers. The ambient temperature affects the thermal management requirements of the battery 10. A first ambient temperature threshold and a second ambient temperature threshold can be set according to actual conditions. By comparing the ambient temperature with the first and second ambient temperature thresholds, the thermal management system 20 can switch to the corresponding operating mode. In different operating modes, the bypass access mechanism 23 enables the heat exchange bypass 22 to achieve different relationships with the heat exchange medium circulation of the heat exchange loop 21.

[0171] An ambient temperature greater than or equal to the first ambient temperature threshold indicates that the current ambient temperature is relatively high, which to some extent increases the cooling demand of battery 10. In Figure 3B, by switching the bypass access mechanism 23, the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21. In this way, in conjunction with the cooling capacity provided by the compression refrigeration cycle circuit 24, the cooling of battery 10 can be accelerated.

[0172] An ambient temperature less than or equal to the second ambient temperature threshold indicates a relatively low current ambient temperature, which reduces the cooling requirement of battery 10 to some extent. Even when the ambient temperature is excessively low, the heating requirement of battery 10 still needs to be considered. In Figure 3C, by switching the bypass access mechanism 23, the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21. This allows a portion of the heat exchange medium to enter the heat exchange bypass 22 for natural cooling. At this time, the compression refrigeration cycle circuit 24 can be shut down, or the compressor 241 in the compression refrigeration cycle circuit 24 can operate at a lower frequency or for a shorter duration, thereby saving energy consumed by the compression refrigeration cycle circuit 24 while meeting the cooling requirements of battery 10. Simultaneously, the fan 26 can be turned on to allow airflow to act on the second heat exchanger 221, thereby improving the heat exchange efficiency of the second heat exchanger 221.

[0173] When the battery 10 needs to be heated, the compression refrigeration cycle loop 24 is kept closed and the heating component 25 is turned on. At this time, the fan can be turned off to blow air. In this way, a part of the heat exchange medium entering the heat exchange bypass 22 is heated by the heating component 25 and flows into the heat exchange loop 21 to exchange heat with the battery in the first heat exchanger 211, thereby meeting the heating requirements of the battery.

[0174] Here, the first and second ambient temperature thresholds can be set to values ​​in the range of [11℃, 17℃], and can be selected as 11℃, 12℃, 13℃, 14℃, 15℃, 16℃ or 17℃, etc. When setting these values, the first ambient temperature threshold must be greater than the second ambient temperature threshold.

[0175] In this embodiment, the state of the bypass access mechanism 23 is switched according to the comparison result of the ambient temperature relative to the threshold, so that the heat exchange bypass 22 can be connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit 21. This can effectively meet the different thermal management requirements under different ambient temperatures and save energy.

[0176] Figure 4 is a schematic diagram of the thermal management system according to a third embodiment of the energy storage system of this disclosure. Referring to Figure 4, in some embodiments, the bypass access mechanism 23 includes a control valve 232, which is disposed in the heat exchange bypass 22 and connected in series with the second heat exchanger 221, so that the heat exchange bypass 22 can be opened or closed by switching the control valve 232.

[0177] Compared to Figure 3A, the bypass access mechanism 23 in Figure 4 includes a control valve 232 located within the heat exchange bypass 22. When the control valve 232 is closed, the heat exchange bypass 22 is disconnected, preventing the heat exchange medium in the heat exchange circuit 21 from being diverted through the heat exchange bypass 22 and then rejoining back into the heat exchange circuit 21. When the control valve 232 is open, the heat exchange bypass 22 is connected, allowing a portion of the heat exchange medium in the heat exchange circuit 21 to be diverted through the heat exchange bypass 22 and then rejoining back into the heat exchange circuit 21.

[0178] The control valve 232 can take any structural form, as long as it can switch the heat exchange bypass 22 on and off, such as a solenoid valve, pneumatic valve, hydraulic valve, etc. In some embodiments, the control valve 232 can not only perform on / off control, but also flow control. In other embodiments, the bypass access mechanism 23 may include both the control valve 232 disposed in the heat exchange bypass 22 and the three-way liquid valve 231 disposed in the heat exchange circuit 21.

[0179] In this embodiment, by providing a control valve 232 in the heat exchange bypass 22 that can open and close the heat exchange bypass 22, the heat exchange bypass 22 can be conveniently connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit 21 as needed.

[0180] Referring to Figure 4, in some embodiments, the second heat exchanger 221 flows downstream of the control valve 232 along the heat exchange medium of the heat exchange bypass 22.

[0181] In this embodiment, the control valve 232 can not only open and close the heat exchange bypass 22, but also directly control the flow rate entering the second heat exchanger 221 upstream of the second heat exchanger 221, so that the flow rate entering the second heat exchanger 221 matches the allowable flow rate of the second heat exchanger 221 to improve the heat exchange efficiency.

[0182] Figure 5A is a structural schematic diagram of the thermal management system according to a fourth embodiment of the energy storage system of this disclosure. Figures 5B and 5C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 5A. Referring to Figure 5A, in some embodiments, the second end of the heat exchange bypass 22 is connected to the second position P2 of the heat exchange loop 21. The second position P2 is downstream of the first position P1 along the heat exchange medium flow of the heat exchange loop 21 and is located on the side of the internal heat exchange channel 2441 adjacent to the first position P1.

[0183] Compared to Figure 3A, in Figure 5A, the second position P2 is located on the side of the internal heat exchange channel 2441 adjacent to the first position P1, rather than on the side of the internal heat exchange channel 2441 away from the first position P1. Figure 5B shows the pump 212 and compressor 241 in operation in bold, and also shows the refrigerant circulation compression refrigeration loop 24 and the heat exchange medium circulation heat exchange loop 21 in bold. Figure 5C shows the pump 212 and compressor 241 in operation in bold, and also shows the heat exchange medium circulation heat exchange loop 21 and heat exchange bypass 22 in bold.

[0184] In Figure 5B, by switching the three-way liquid valve 231, the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21. In this way, in conjunction with the cooling capacity provided by the compression refrigeration cycle circuit 24, the cooling of the battery 10 can be accelerated.

[0185] In Figure 5C, by switching the three-way liquid valve 231, the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21. A portion of the heat exchange medium is diverted to the heat exchange bypass 22 for natural cooling, while the other portion flows in the flow path section from the first position P1 to the second position P2 in the heat exchange circuit 21. The heat exchange medium flowing out of the heat exchange bypass 22 merges with the heat exchange medium flowing in the flow path section from the first position P1 to the second position P2, and then enters the internal heat exchange channel 2441 of the evaporator 244. This increases the amount of heat exchange medium flowing through the internal heat exchange channel 2441 of the evaporator 244, allowing more heat exchange medium to receive the cooling capacity provided by the compression refrigeration cycle circuit 24.

[0186] In this embodiment, the second position P2 is positioned on the side of the internal heat exchange channel 2441 adjacent to the first position P1. This allows the heat exchange medium flowing out of the heat exchange bypass 22 to merge with the heat exchange medium flowing through the flow path from the first position P1 to the second position P2 before entering the internal heat exchange channel 2441 of the evaporator 244. This increases the amount of heat exchange medium flowing through the internal heat exchange channel 2441 of the evaporator 244, allowing more heat exchange medium to receive the cooling capacity provided by the compression refrigeration cycle loop 24.

[0187] Figure 6A is a structural schematic diagram of the thermal management system according to a fifth embodiment of the energy storage system of this disclosure. Figures 6B and 6C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 6A. Referring to Figure 6A, in some embodiments, the thermal management system 20 further includes a heating component 25, which is disposed in the heat exchange circuit 21 and configured to heat the heat exchange medium flowing through the heat exchange circuit 21 when the heating function is activated.

[0188] Compared to Figure 3A, in Figure 6A, the heating component 25 is disposed in the heat exchange circuit 21. This ensures that when the battery 10 requires heating, the heat exchange medium in the heat exchange circuit 21 can be sufficiently heated by the heating component 25, thereby improving the battery heating efficiency. In other embodiments, the thermal management system 20 may include both the heating component 25 disposed in the heat exchange bypass 22 and the heating component 25 disposed in the heat exchange circuit 21.

[0189] In this embodiment, by setting a heating component 25 in the heat exchange circuit 21, the heating function of the heating component 25 can be turned on and off to meet the thermal management requirements under different ambient temperatures as needed.

[0190] Referring to Figure 6A, in some embodiments, the thermal management system 20 further includes a compression refrigeration loop 24, which includes an evaporator 244. The evaporator 244 also has an internal heat exchange channel 2441, which is connected in series with the heat exchange loop 21 and exchanges heat with the compression refrigeration loop 24 through the evaporator 244. The first end of the heat exchange bypass 22 is connected to a first position P1 of the heat exchange loop 21, which is located downstream of the first heat exchanger 211 along the heat exchange medium flow of the heat exchange loop 21. The heating assembly 25 is located between the first position P1 and the internal heat exchange channel 2441.

[0191] The heating assembly 25 can limit the flow rate through the heat exchange circuit 21, thereby achieving a certain flow distribution between the heat exchange circuit 21 and the heat exchange bypass 22. Specifically, the heating assembly 25 may include a heater 251 and a flow control valve 252 connected in parallel. Through the allowable flow rate of the heater 251 and the flow control function of the flow control valve 252, the flow rate of a portion of the heat exchange medium entering the heat exchange bypass 22 and a portion of the heat exchange medium entering the internal heat exchange channel 2441 of the evaporator 244 can be distributed, so that the flow rate in the heat exchange bypass 22 conforms to the allowable flow rate range of the second heat exchanger 221, reducing pressure drop and improving heat exchange efficiency.

[0192] Figure 6B shows the pump 212 and compressor 241 in operation in bold, as well as the refrigerant circulation compression refrigeration loop 24 and the heat exchange medium circulation heat exchange loop 21 in bold. Figure 6C shows the pump 212 in operation in bold, as well as the heat exchange medium circulation heat exchange loop 21 and the heat exchange bypass 22 in bold.

[0193] In Figure 6B, by switching the three-way liquid valve 231, the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21. At this time, the heating component 25 turns off the heating function, and the heat exchange circuit 21 receives the cooling capacity provided by the compression refrigeration cycle circuit 24 in the evaporator 244, which can accelerate the cooling of the battery 10.

[0194] In Figure 6C, by switching the three-way liquid valve 231, the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21. A portion of the heat exchange medium is diverted to the heat exchange bypass 22 for natural cooling, while the other portion flows to the heating assembly 25. At this time, at least one of the three-way liquid valve 231 and the heating assembly 25 can achieve the function of flow distribution. The heating assembly 25 can turn on the heating function according to the heating requirements of the battery 10, or turn off the heating function according to the cooling requirements of the battery.

[0195] Figure 7A is a schematic diagram of the thermal management system according to a sixth embodiment of the energy storage system of this disclosure. Figures 7B and 7C are schematic diagrams of the medium circulation corresponding to different modes of the thermal management system in the embodiment shown in Figure 7A. Compared with Figure 6A, in Figure 7A, the second position P2 is located on the side of the internal heat exchange channel 2441 adjacent to the first position P1, rather than on the side of the internal heat exchange channel 2441 away from the first position P1. Figure 7B shows the pump 212 and compressor 241 in operation in bold, and also shows the compression refrigeration cycle loop 24 of the refrigerant circulation and the heat exchange loop 21 of the heat exchange medium circulation in bold. Figure 7C shows the pump 212 and compressor 241 in operation in bold, and also shows the heat exchange loop 21 and heat exchange bypass 22 of the heat exchange medium circulation in bold.

[0196] In Figure 7B, by switching the three-way liquid valve 231, the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21. In this way, in conjunction with the cooling capacity provided by the compression refrigeration cycle circuit 24, the cooling of the battery 10 can be accelerated.

[0197] In Figure 7C, by switching the three-way liquid valve 231, the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21. A portion of the heat exchange medium is diverted to the heat exchange bypass 22 for natural cooling, while the other portion flows in the flow path section from the first position P1 to the second position P2 in the heat exchange circuit 21. At this time, at least one of the three-way liquid valve 231 and the heating assembly 25 can achieve the function of flow distribution between the heat exchange bypass 22 and the heat exchange circuit 21. The heat exchange medium flowing out of the heat exchange bypass 22 merges with the heat exchange medium flowing in the flow path section from the first position P1 to the second position P2, and then enters the internal heat exchange channel 2441 of the evaporator 244. This increases the amount of heat exchange medium flowing through the internal heat exchange channel 2441 of the evaporator 244, allowing more heat exchange medium to receive the cooling capacity provided by the compression refrigeration cycle circuit 24.

[0198] Based on the energy storage systems of the above embodiments of this disclosure, in one aspect of this disclosure, a control method for the energy storage system of any of the foregoing embodiments is also provided. The control method includes: through a switching operation of the bypass access mechanism 23, causing the heat exchange bypass 22 to connect to or disconnect from the heat exchange medium circulation of the heat exchange circuit 21.

[0199] Each step in the control method can be implemented by a processor in the energy storage system or a processor in the thermal management system 20 executing instructions in the memory. In some embodiments, the thermal management system 20 further includes a processor that can communicate with the bypass access mechanism 23 via wired or wireless means to implement switching control of the bypass access mechanism 23.

[0200] In this embodiment, the switching operation of the bypass access mechanism 23 can enable the access or disconnection of the heat exchange bypass 22 with a second heat exchanger 221 that can achieve natural cooling from the heat exchange medium circulation of the heat exchange circuit 21. This allows the thermal management system 20 to establish different heat exchange medium circulation forms according to actual conditions, which can improve the adaptability of the energy storage system to thermal management and help meet the needs of improving thermal management efficiency and saving energy consumption.

[0201] In some embodiments, the control method further includes: adjusting the flow distribution relationship between the heat exchange circuit 21 and the heat exchange bypass 22 by means of the bypass access mechanism 23 when the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21.

[0202] In this embodiment, the flow distribution relationship between the heat exchange circuit 21 and the heat exchange bypass 22 can be adjusted through the bypass access mechanism 23 according to the actual thermal management requirements and the allowable flow of the devices in the thermal management system. This is beneficial to improving the heat exchange effect of the system and reducing the system energy consumption.

[0203] In some embodiments, the step of connecting or disconnecting the heat exchange bypass 22 from the heat exchange medium circulation of the heat exchange circuit 21 through the switching operation of the bypass access mechanism 23 includes: disconnecting the heat exchange bypass 22 from the heat exchange medium circulation of the heat exchange circuit 21 through the switching operation of the bypass access mechanism 23 in response to an ambient temperature greater than or equal to a first ambient temperature threshold; and connecting the heat exchange bypass 22 to the heat exchange medium circulation of the heat exchange circuit 21 through the switching operation of the bypass access mechanism 23 in response to an ambient temperature less than or equal to a second ambient temperature threshold; wherein the first ambient temperature threshold is greater than the second ambient temperature threshold.

[0204] An ambient temperature greater than or equal to the first ambient temperature threshold indicates that the current ambient temperature is relatively high, which to some extent increases the cooling demand of battery 10. By switching the bypass access mechanism 23, the heat exchange bypass 22 is disconnected from the heat exchange medium circulation of the heat exchange circuit 21. In this way, in conjunction with the cooling capacity provided by the compression refrigeration cycle circuit 24, the cooling of battery 10 can be accelerated.

[0205] An ambient temperature less than or equal to the second ambient temperature threshold indicates a relatively low current ambient temperature, which reduces the cooling requirement of battery 10 to some extent. Even when the ambient temperature is excessively low, the heating requirement of battery 10 still needs to be considered. By switching the bypass access mechanism 23, the heat exchange bypass 22 is connected to the heat exchange medium circulation of the heat exchange circuit 21. This allows a portion of the heat exchange medium to enter the heat exchange bypass 22 for natural cooling. At this time, the compression refrigeration cycle circuit 24 can be shut down, or the compressor 241 in the compression refrigeration cycle circuit 24 can operate at a lower frequency or for a shorter duration, thereby saving energy consumed by the compression refrigeration cycle circuit 24 while meeting the cooling requirements of battery 10. Simultaneously, the fan 26 can be turned on to allow airflow to act on the second heat exchanger 221, thereby improving the heat exchange efficiency of the second heat exchanger 221.

[0206] In this embodiment, the state of the bypass access mechanism 23 is switched according to the comparison result of the ambient temperature relative to the threshold, so that the heat exchange bypass 22 can be connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit 21. This can effectively meet the different thermal management requirements under different ambient temperatures and save energy.

[0207] This specification describes multiple embodiments in a progressive manner, with each embodiment having a different focus. Similar or identical parts between embodiments can be referred to interchangeably. For the control method embodiments, since their overall structure and content correspond to those in the system embodiments, the description is relatively simple; relevant parts can be referred to in the descriptions of the system embodiments.

[0208] The embodiments of this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0209] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. An energy storage system, comprising: Battery (10) for storing and releasing energy; and Thermal management system (20); The thermal management system (20) includes: The heat exchange circuit (21) includes a first heat exchanger (211) for exchanging heat with the battery (10); A heat exchange bypass (22) includes a second heat exchanger (221) capable of natural cooling; and A bypass access mechanism (23) is provided in at least one of the heat exchange circuit (21) and the heat exchange bypass (22); The bypass access mechanism (23) switches the heat exchange bypass (22) to either connect to or disconnect from the heat exchange medium circulation of the heat exchange circuit (21).

2. The energy storage system of claim 1, wherein, The bypass access mechanism (23) includes: A three-way liquid valve (231) is installed in the heat exchange circuit (21) and connected in series with the first heat exchanger (211); The first end of the heat exchange bypass (22) is connected to the heat exchange circuit (21) through the three-way liquid valve (231). The first end of the heat exchange bypass (22) is connected to or disconnected from the heat exchange circuit (21) by switching the three-way liquid valve (231). The second end of the heat exchange bypass (22) is connected to the heat exchange circuit (21).

3. The energy storage system of claim 2, wherein, The three-way liquid valve (231) is located downstream of the first heat exchanger (211) along the heat exchange medium flow direction of the heat exchange circuit (21).

4. The energy storage system of any of claims 2-3, wherein, The three-way liquid valve (231) is configured to adjust the flow distribution relationship between the heat exchange circuit (21) and the heat exchange bypass (22) when the heat exchange bypass (22) is connected to the heat exchange circuit (21) for heat exchange medium circulation.

5. The energy storage system of any of claims 1-4, wherein, The second heat exchanger (221) includes a microchannel heat exchanger (2211).

6. The energy storage system of claim 1, wherein, The bypass access mechanism (23) includes: A control valve (232) is provided in the heat exchange bypass (22) and connected in series with the second heat exchanger (221) so that the heat exchange bypass (22) can be turned on or off by switching the control valve (232).

7. The energy storage system of claim 6, wherein, The second heat exchanger (221) is located downstream of the control valve (232) along the heat exchange medium flow of the heat exchange bypass (22).

8. The energy storage system of any of claims 1-7, wherein, The thermal management system (20) also includes: A compression refrigeration cycle loop (24), the compression refrigeration cycle loop (24) including an evaporator (244); The evaporator (244) also has an internal heat exchange channel (2441), which is connected in series with the heat exchange circuit (21) and exchanges heat with the compression refrigeration cycle circuit (24) through the evaporator (244).

9. The energy storage system of claim 8, wherein, The heat exchange circuit (21) further includes a pump (212), which is connected in series with the first heat exchanger (211) and the internal heat exchange channel (2441) and is located between the first heat exchanger (211) and the internal heat exchange channel (2441).

10. The energy storage system of claim 8 or 9, wherein, The bypass access mechanism (23) includes a three-way liquid valve (231), which is located at a first position (P1) in the heat exchange circuit (21). The first position (P1) is located downstream of the first heat exchanger (211) along the heat exchange medium flow of the heat exchange circuit (21). The first end of the heat exchange bypass (22) is connected to the three-way liquid valve (231). The three-way liquid valve (231) is configured to adjust the flow distribution relationship between the heat exchange circuit (21) and the heat exchange bypass (22) when the heat exchange bypass (22) is connected to the heat exchange medium circulation of the heat exchange circuit (21).

11. The energy storage system of claim 10, wherein, The second end of the heat exchange bypass (22) is connected to the second position (P2) of the heat exchange circuit (21). The second position (P2) is located downstream of the first position (P1) along the heat exchange medium flow direction of the heat exchange circuit (21) and is located on the side of the internal heat exchange channel (2441) away from the first position (P1).

12. The energy storage system of claim 10, wherein, The second end of the heat exchange bypass (22) is connected to the second position (P2) of the heat exchange circuit (21). The second position (P2) is located downstream of the first position (P1) along the heat exchange medium flow direction of the heat exchange circuit (21) and is located on the side of the internal heat exchange channel (2441) adjacent to the first position (P1).

13. The energy storage system of any of claims 8-12, wherein, The compression refrigeration cycle loop (24) further includes a condenser (242), and the thermal management system (20) further includes a fan (26). When the fan (26) turns on the air outlet, it causes the airflow to act on the condenser (242) and the second heat exchanger (221).

14. The energy storage system of any of claims 1-13, wherein, The thermal management system (20) also includes: A heating assembly (25), disposed in the heat exchange bypass (22), is configured to heat the heat exchange medium flowing through the heat exchange bypass (22) when the heating function is activated; and A fan (26) is configured to cause airflow to act on the second heat exchanger (221) when the outlet is turned on.

15. The energy storage system of claim 14, wherein, The fan (26) is configured to shut off the air outlet when the heating component (25) turns on the heating function, and turn on the air outlet when the heating component (25) turns off the heating function, while the heat exchange medium is circulating in the heat exchange bypass (22) connected to the heat exchange circuit (21).

16. The energy storage system of any of claims 1-13, wherein, The thermal management system (20) also includes: A heating component (25) is disposed in the heat exchange circuit (21) and is configured to heat the heat exchange medium flowing through the heat exchange circuit (21) when the heating function is turned on.

17. The energy storage system of claim 16, wherein, The thermal management system (20) also includes: A compression refrigeration cycle loop (24), the compression refrigeration cycle loop (24) including an evaporator (244); The evaporator (244) also has an internal heat exchange channel (2441), which is connected in series with the heat exchange circuit (21) and exchanges heat with the compression refrigeration cycle circuit (24) through the evaporator (244); the first end of the heat exchange bypass (22) is connected to the first position (P1) of the heat exchange circuit (21), which is located downstream of the first heat exchanger (211) along the heat exchange medium flow of the heat exchange circuit (21); the heating component (25) is located between the first position (P1) and the internal heat exchange channel (2441).

18. The energy storage system of any of claims 14-17, wherein, The heating assembly (25) includes: Heater (251), used to turn the heating function on or off; and A flow control valve (252) is connected in parallel with the heater (251) and is used to control the flow rate of the heat exchange medium through the flow control valve (252).

19. The energy storage system of any of claims 1-18, wherein, The bypass access mechanism (23) is configured as follows: In response to an ambient temperature greater than or equal to a first ambient temperature threshold, the system switches to a state that disconnects the heat exchange bypass (22) from the heat exchange medium circulation of the heat exchange loop (21). In response to an ambient temperature less than or equal to a second ambient temperature threshold, the system switches to a state in which the heat exchange bypass (22) is connected to the heat exchange medium circulation of the heat exchange circuit (21); Wherein, the first ambient temperature threshold is greater than the second ambient temperature threshold.

20. A control method for an energy storage system according to any one of claims 1-19, comprising: By switching the bypass access mechanism (23), the heat exchange bypass (22) can be connected to or disconnected from the heat exchange medium circulation of the heat exchange circuit (21).

21. The control method according to claim 20, further comprising: When the heat exchange medium is circulating in the heat exchange circuit (21) through the heat exchange bypass (22), the flow distribution relationship between the heat exchange circuit (21) and the heat exchange bypass (22) is adjusted by the bypass access mechanism (23).

22. The control method according to claim 20 or 21, wherein The steps of connecting the heat exchange bypass (22) to or disconnecting from the heat exchange medium circulation of the heat exchange circuit (21) through the switching operation of the bypass access mechanism (23) include: In response to an ambient temperature greater than or equal to a first ambient temperature threshold, the heat exchange bypass (22) is disconnected from the heat exchange medium circulation state of the heat exchange circuit (21) by the switching operation of the bypass access mechanism (23). In response to an ambient temperature less than or equal to a second ambient temperature threshold, the heat exchange bypass (22) is connected to the heat exchange medium circulation state of the heat exchange circuit (21) through the switching operation of the bypass access mechanism (23); Wherein, the first ambient temperature threshold is greater than the second ambient temperature threshold.

Images