Energy storage system

Abstract

An energy storage system, comprising a battery, a power conversion system and a thermal management system. The thermal management system comprises: a first heat exchange flow path, comprising a first pump and a first heat exchanger used for performing heat exchange with the battery, and being configured to form a first heat exchange loop when the first pump is turned on; a second heat exchange flow path, comprising a second pump and a second heat exchanger used for performing heat exchange with the power conversion system, and being configured to form a second heat exchange loop when the second pump is turned on; and a flow path switching mechanism, the first heat exchange flow path and the second heat exchange flow path being operably communicated by means of the flow path switching mechanism. By means of the opening and closing operations of the first pump and the second pump and the switching operations of the flow path switching mechanism, the working modes of the thermal management system can be switched, such that in a first working mode, the first heat exchange loop and the second heat exchange loop operate independently, or in a second working mode, a combined heat exchange loop comprising at least part of flow paths of the first heat exchange loop and the second heat exchange flow path is formed.

Description

Energy storage system

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to CN application number 202411612911.X, 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. 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, an energy storage converter, and a thermal management system, wherein the thermal management system includes:

[0006] The first heat exchange path includes a first pump and a first heat exchanger for exchanging heat with the battery, and is configured to form a first heat exchange loop when the first pump is turned on.

[0007] The second heat exchange path includes a second pump and a second heat exchanger for heat exchange with the energy storage converter, and is configured to form a second heat exchange loop when the second pump is turned on; and

[0008] A flow path switching mechanism, wherein the first heat exchange flow path and the second heat exchange flow path are operably connected through the flow path switching mechanism;

[0009] The working mode of the thermal management system is switched by opening and closing the first pump and the second pump and switching the flow path switching mechanism. In the first working mode of the thermal management system, the first heat exchange circuit and the second heat exchange circuit operate independently, or in the second working mode of the thermal management system, a heat exchange combined circuit is formed, which includes at least part of the flow path of the first heat exchange circuit and the second heat exchange flow path.

[0010] In this embodiment, the first heat exchanger in the first heat exchange path and the second heat exchanger in the second heat exchange path can exchange heat with the battery and the energy storage converter, respectively. The first heat exchange path and the second heat exchange path are operably connected through the path switching mechanism. According to the control commands issued by the processor to the first pump in the first heat exchange path, the second pump in the second heat exchange path, and the path switching mechanism, the first heat exchange path and the second heat exchange path can either form heat exchange loops and operate independently, thereby being configured and controlled independently according to the thermal management requirements of the battery and the energy storage converter, meeting more flexible thermal management requirements, or at least a portion of the flow paths of the first heat exchange path and the second heat exchange path can form a combined heat exchange loop to meet the thermal management requirements of the battery and the energy storage converter.

[0011] In some embodiments, the flow path switching mechanism includes:

[0012] At least two connected flow paths, each connected to the first heat exchange flow path and the second heat exchange flow path at both ends, respectively; and

[0013] A control valve, disposed in at least one of the at least two connected flow paths, is configured to switch the on / off state of the connected flow path in which the control valve is disposed;

[0014] In the first operating mode of the thermal management system, both the first pump and the second pump are turned on, and the control valve is switched to the off state to form an independently operating first heat exchange circuit and second heat exchange circuit; or in the second operating mode of the thermal management system, the first pump is turned on, the second pump is turned off, and the control valve is switched to the on state to form a combined heat exchange circuit driven by the second pump in the second operating mode of the thermal management system.

[0015] In this embodiment, a connecting flow path is provided at both ends, linking the first and second heat exchange flow paths. By controlling the on / off state of the control valve, the first and second heat exchange flow paths can be easily connected to form a loop, or disconnected to achieve independent operation. Combined with the on / off control of the first and second pumps, a first and second operating mode of the thermal management system can be effectively implemented. In the second operating mode, a heat exchange combination loop driven by the second pump is formed. This prevents the need for flow characteristic matching between the first and second pumps from affecting the independence of the thermal management capabilities achieved by the first and second heat exchange flow paths. Furthermore, single-pump drive reduces system energy consumption and simplifies control complexity.

[0016] In some embodiments, the at least two connected flow paths include:

[0017] A first connecting flow path, one end of which is connected to a first position of the first heat exchange flow path, and the other end of which is connected to a second position of the second heat exchange flow path; and

[0018] The second connecting flow path has one end connected to the third position of the first heat exchange flow path and the other end connected to the fourth position of the second heat exchange flow path.

[0019] The second heat exchange flow path includes a first heat exchange flow path and a second heat exchange flow path. One end of the first heat exchange flow path is connected to one end of the second heat exchange flow path at the second position, and the other end of the first heat exchange flow path is connected to the other end of the second heat exchange flow path at the fourth position. The second pump is located in the first heat exchange flow path. The heat exchange combination circuit includes the first heat exchange flow path and the second heat exchange flow path.

[0020] In this embodiment, based on the end connection relationship of the first part of the heat exchange flow path and the second part of the heat exchange flow path, the second heat exchange flow path is divided into the first part of the heat exchange flow path and the second part of the heat exchange flow path at the second position and the fourth position. In this way, when the second pump is turned off, the first part of the heat exchange flow path containing the second pump is also disconnected. Thus, the first part of the heat exchange flow path and the second part of the heat exchange flow path are connected through the first connecting flow path and the second connecting flow path to form a heat exchange combination loop driven by the first pump.

[0021] In some embodiments, the second heat exchanger is located within the second portion of the heat exchange flow path.

[0022] In this embodiment, the second heat exchanger is set in the second heat exchange flow path, so that the heat exchange of the energy storage converter can be realized in both the first and second working modes of the thermal management system, so as to meet the thermal management requirements of the energy storage converter under different operating conditions.

[0023] In some embodiments, the second heat exchange path further includes:

[0024] The natural cooling heat exchanger is located within the second part of the heat exchange flow path.

[0025] In this embodiment, a natural cooling heat exchanger is installed in the second heat exchange flow path. It can participate in the natural heat exchange between the heat exchange medium in the heat management system and the outside in both the first and second working modes of the heat management system, which is beneficial to further reduce system energy consumption.

[0026] In some embodiments, the natural cooling heat exchanger includes a microchannel heat exchanger.

[0027] In this embodiment, the natural cooling heat exchanger adopts a microchannel heat exchanger, which can achieve higher heat exchange efficiency, improve the energy efficiency of the system, and occupy less space.

[0028] In some embodiments, the second position is located at the outlet side of the second pump, and the fourth position is located at the inlet side of the second pump; the second heat exchange path further includes:

[0029] A one-way valve is located within the first part of the heat exchange flow path and between the outlet of the second pump and the second position;

[0030] The one-way valve is configured to unidirectionally flow from the second pump to the second position.

[0031] The one-way valve can enable the heat exchange medium to flow unidirectionally from the second pump to the second position. This can effectively reduce the risk of backflow of heat exchange medium with high pressure at the outlet side of the second pump back to the second pump, which could cause pump damage, and also helps maintain stable system pressure.

[0032] In some embodiments, the thermal management system further includes:

[0033] Compression refrigeration cycle loop, including evaporator;

[0034] In this process, a portion of the first heat exchange flow path passes through the evaporator and exchanges heat with the compression refrigeration cycle loop through the evaporator.

[0035] In this embodiment, cooling is provided to the heat exchange medium in the first heat exchange flow path through heat exchange between the compression refrigeration cycle loop and the first heat exchange flow path. This improves the thermal management efficiency of the first heat exchange flow path and enhances the configuration flexibility for different thermal management needs. Furthermore, the compression refrigeration cycle loop achieves high cooling efficiency, and by exchanging heat with the first heat exchange flow path, it effectively reduces the temperature of the heat exchange medium flowing in the first heat exchange flow path, thereby increasing the cooling capacity of the loop containing the first heat exchange flow path.

[0036] In some embodiments, a portion of the first heat exchange path passing through the evaporator is located between the first position and the third position.

[0037] In this embodiment, by positioning a portion of the first heat exchange flow path through the evaporator between the first position and the third position, the heat exchange medium of the first heat exchange flow path is diverted to meet the thermal management requirements of the energy storage converter, and the cooling effect can be improved by absorbing cold energy through the evaporator.

[0038] In some embodiments, the first position is located at the outlet side of the first pump, and the third position is located at the inlet side of the first pump; the control valve is disposed at the first position and configured to control the on / off state and flow rate of the first connecting flow path.

[0039] In this embodiment, the second heat exchange flow path is connected to the inlet and outlet sides of the first pump through the second connecting flow path and the first connecting flow path, respectively. The on / off state and flow rate of the first connecting flow path are controlled by the control valve. In addition to meeting the switching needs between the first and second working modes of the thermal management system, the flow rate distribution of the branch flow paths in the heat exchange combination loop can also be realized to improve heat exchange efficiency and improve system performance.

[0040] In some embodiments, the thermal management system further includes:

[0041] An expansion tank is disposed in the second connecting flow path, the first heat exchange flow path, or the second heat exchange flow path, adjacent to the third position, or adjacent to the fourth position.

[0042] Since the first and second heat exchange flow paths are connected in the second connecting flow path, the expansion tank can be placed in the second connecting flow path, at a position adjacent to the third position in the first heat exchange flow path, or at a position adjacent to the fourth position in the second heat exchange flow path. This compensates for the volume expansion or contraction of the heat exchange medium in the first or second heat exchange flow path due to temperature changes and maintains their pressure stability. This reduces the number of expansion tanks required.

[0043] In some embodiments, the thermal management system further includes a processor configured to:

[0044] In response to an ambient temperature greater than or equal to a first ambient temperature threshold, the thermal management system switches to a first operating mode; and

[0045] In response to an ambient temperature being less than or equal to a second ambient temperature threshold, the thermal management system switches to a second operating mode.

[0046] Wherein, the first ambient temperature threshold is greater than the second ambient temperature threshold.

[0047] In this embodiment, the working mode of the thermal management system is switched according to the comparison result of the ambient temperature relative to the threshold, which can effectively meet the different thermal management needs under different ambient temperatures and save energy.

[0048] In some embodiments, the thermal management system further includes:

[0049] A compression refrigeration cycle includes an evaporator and a compressor, wherein a portion of the first heat exchange flow path passes through the evaporator and exchanges heat with the compression refrigeration cycle through the evaporator;

[0050] The processor is configured as follows:

[0051] In the first operating mode of the thermal management system, the compressor is operated at a first operating frequency; and

[0052] In the second operating mode of the thermal management system, the compressor is shut down or operated at a second operating frequency;

[0053] The second operating frequency is less than the first operating frequency.

[0054] In this embodiment, controlling the start-up and shutdown or operating frequency of the compressor according to the working mode of the thermal management system can meet the thermal management requirements under different ambient temperatures and effectively reduce energy consumption.

[0055] In some embodiments, the flow path switching mechanism includes at least two connected flow paths, each connected to the first heat exchange flow path and the second heat exchange flow path at both ends, respectively. The thermal management system further includes a heating mechanism, which is disposed in at least one of the at least two connected flow paths and is configured to heat the heat exchange medium flowing through the connected flow path where the heating mechanism is located when the heating function is activated.

[0056] The processor is configured as follows:

[0057] In the first operating mode of the thermal management system, the heating mechanism is deactivated; and

[0058] In the second operating mode of the thermal management system, the heating mechanism is turned on or off.

[0059] In this embodiment, controlling the opening and closing of the heating mechanism according to the working mode of the thermal management system can meet the thermal management requirements under different ambient temperatures and effectively save energy consumption.

[0060] In some embodiments, the at least two connected flow paths include:

[0061] A first connecting flow path, one end of which is connected to a first position of the first heat exchange flow path, and the other end of which is connected to a second position of the second heat exchange flow path; and

[0062] The second connecting flow path has one end connected to the third position of the first heat exchange flow path and the other end connected to the fourth position of the second heat exchange flow path.

[0063] The heating mechanism is disposed in the first connecting flow path or the second connecting flow path and is configured to heat the heat exchange medium flowing through the first connecting flow path or the second connecting flow path where the heating mechanism is located when the heating function is turned on.

[0064] In this embodiment, by setting the heating mechanism in the first or second connecting flow path and heating the heat exchange medium flowing through the first or second connecting flow path where the heating mechanism is located when the heating function is turned on, the heating requirements of the battery can be met.

[0065] In some embodiments, the heating mechanism includes:

[0066] The heater is configured to turn the heating function on or off according to instructions from the processor.

[0067] In this embodiment, by heating the heat exchange medium with a heater, the battery temperature can be increased by the first heat exchanger when the battery temperature is low.

[0068] In some embodiments, the heating mechanism further includes:

[0069] A flow control valve is connected in parallel with the heater;

[0070] The flow control valve is configured to control the flow rate of the heat exchange medium passing through the flow control valve according to the instructions of the processor.

[0071] Considering that there may be a difference between the flow rate of the heat exchange medium and the allowable flow rate of the heater in the heat exchange combination circuit, which may create flow resistance at the heater location, the risk of flow resistance in the heater can be reduced by controlling the flow distribution through a flow control valve connected in parallel with the heater, thereby improving the circulation efficiency of the heat exchange medium and the energy efficiency of thermal management. Attached Figure Description

[0072] 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.

[0073] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein:

[0074] Figure 1 is a schematic diagram of the structure of some embodiments of the energy storage system according to the present disclosure;

[0075] Figure 2 is a schematic diagram of control signal connections according to an embodiment of the energy storage system of this disclosure;

[0076] Figure 3 is a schematic diagram of the structure of the thermal management system according to some embodiments of the energy storage system of this disclosure;

[0077] Figure 4 is a schematic diagram of the structure of the thermal management system according to some other embodiments of the energy storage system of the present disclosure;

[0078] Figure 5 is a schematic diagram of the medium circulation in the thermal management system in the first working mode of the embodiment shown in Figure 4;

[0079] Figure 6 is a schematic diagram of the medium circulation in the thermal management system under the second working mode of the embodiment shown in Figure 4;

[0080] Figure 7 is a schematic diagram of another medium circulation in the thermal management system under the second working mode of the embodiment shown in Figure 4;

[0081] Figure 8 is a schematic diagram of the structure of the thermal management system according to some other embodiments of the energy storage system of the present disclosure;

[0082] Figure 9 is a schematic diagram of the medium circulation in the thermal management system in the first working mode of the embodiment shown in Figure 8;

[0083] Figure 10 is a schematic diagram of the medium circulation in the thermal management system under the second working mode of the embodiment shown in Figure 8;

[0084] Figure 11 is a schematic diagram of another medium circulation in the thermal management system under the second working mode of the embodiment shown in Figure 8.

[0085] 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.

[0086] The labels in the attached diagrams represent: 10 - battery; 20 - power conversion system (PCS); 30-Thermal Management System; 31-First Heat Exchange Flow Path; 311-First Pump; 312-First Heat Exchanger; 32-Second Heat Exchange Flow Path; 321-Second Pump; 322-Second Heat Exchanger; 323-First Partial Heat Exchange Flow Path; 324-Second Partial Heat Exchange Flow Path; 325-Natural Cooling Heat Exchanger; 3251-Microchannel Heat Exchanger; 326-One-Way Valve; 327-Fan; 33-Connecting Flow Path; 331-First Connecting Flow Path; 332-Second Connecting Flow Path; 333-Expansion Tank; 34-Flow Path Switching Mechanism; 341-Control Valve; 35-Processor; 36-Compression Refrigeration Cycle Loop; 361-Compressor; 362-Condenser; 363-Throttling Device; 364-Evaporator; 365-Gas-Liquid Separator; 37-Heating Mechanism; 371-Heater; 372-Flow Control Valve; p1 - ​​First position; p2 - Second position; p3 - Third position; p4 - Fourth position. Detailed Implementation

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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).

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] 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.

[0106] 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.

[0107] 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).

[0108] 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.

[0109] In some embodiments, the negative electrode sheet may include a negative current collector substrate.

[0110] 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.).

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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.

[0118] 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.

[0119] As an example, liquid electrolytes include electrolyte salts and solvents.

[0120] 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.

[0121] 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.

[0122] As an example, gel electrolytes include a polymer-based backbone network combined with an ionic liquid—a lithium salt.

[0123] As an example, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0124] 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.

[0125] 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.

[0126] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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).

[0131] 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.

[0132] 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.

[0133] 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.

[0134] In some related technologies, to meet the cooling requirements of batteries and power converters (PCS) in energy storage systems, the thermal management system uses liquid cooling for batteries and air cooling for PCS, or employs two independent liquid cooling systems to cool the batteries and PCS separately. This type of thermal management system suffers from large size and weight, and relatively low energy efficiency.

[0135] Research has revealed that the thermal management of the battery and the energy storage converter group in the cooling path of the thermal management system of related technologies are mutually influential, making it difficult to independently achieve thermal management of the battery and the PCS to meet different thermal management requirements.

[0136] In view of this, the present disclosure provides an energy storage system and its control method, which is beneficial to improving the ability to meet the different thermal management requirements of batteries and energy storage converters in the energy storage system.

[0137] In one aspect of this disclosure, an energy storage system is provided, comprising: a battery, an energy storage converter, and a thermal management system, wherein the thermal management system includes: a first heat exchange path including a first pump and a first heat exchanger for heat exchange with the battery, and configured to form a first heat exchange loop when the first pump is turned on; a second heat exchange path including a second pump and a second heat exchanger for heat exchange with the energy storage converter, and configured to form a second heat exchange loop when the second pump is turned on; and a path switching mechanism, wherein the first heat exchange path and the second heat exchange path are operatively connected via the path switching mechanism; wherein the operating mode of the thermal management system is switched by opening and closing operations of the first pump and the second pump and by switching operations of the path switching mechanism, such that in a first operating mode of the thermal management system, the first heat exchange loop and the second heat exchange loop operate independently, or in a second operating mode of the thermal management system, a combined heat exchange loop is formed, the combined heat exchange loop including at least a portion of the flow paths of the first heat exchange loop and the second heat exchange path.

[0138] In this embodiment, the first heat exchanger in the first heat exchange path and the second heat exchanger in the second heat exchange path can exchange heat with the battery and the energy storage converter, respectively. The first heat exchange path and the second heat exchange path are operably connected through the path switching mechanism. According to the control commands issued by the processor to the first pump in the first heat exchange path, the second pump in the second heat exchange path, and the path switching mechanism, the first heat exchange path and the second heat exchange path can either form heat exchange loops and operate independently, thereby being configured and controlled independently according to the thermal management requirements of the battery and the energy storage converter, meeting more flexible thermal management requirements, or at least a portion of the flow paths of the first heat exchange path and the second heat exchange path can form a combined heat exchange loop to meet the thermal management requirements of the battery and the energy storage converter.

[0139] Figure 1 is a structural schematic diagram of some embodiments of the energy storage system according to the present disclosure. Figure 2 is a control signal connection schematic diagram of an embodiment of the energy storage system according to the present disclosure. Figure 3 is a structural schematic diagram of the thermal management system of some embodiments of the energy storage system according to the present disclosure.

[0140] Referring to Figures 1-3, this disclosure provides an energy storage system, including a battery 10, an energy storage converter 20, and a thermal management system 30. The thermal management system 30 includes a first heat exchange path 31, a second heat exchange path 32, and a path switching mechanism 34. The first heat exchange path 31 includes a first pump 311 and a first heat exchanger 312 for heat exchange with the battery 10, and is configured to form a first heat exchange loop when the first pump 311 is turned on. The second heat exchange path 32 includes a second pump 321 and a second heat exchanger 322 for heat exchange with the energy storage converter 20, and is configured to form a second heat exchange loop when the second pump 321 is turned on. The first heat exchange path 31 and the second heat exchange path 32 are operably connected through the path switching mechanism 34. By opening and closing the first pump 311 and the second pump 321 and switching the flow path switching mechanism 34, the working mode of the thermal management system is switched, so that in the first working mode of the thermal management system 30, the first heat exchange circuit and the second heat exchange circuit operate independently, or in the second working mode of the thermal management system 30, a heat exchange combination circuit is formed, the heat exchange combination circuit including at least part of the flow path of the first heat exchange circuit and the second heat exchange flow path 32.

[0141] Battery 10 is used to store and release energy, and energy storage converter 20 is used to connect the power supply source and battery 10. The power supply source may include the power grid or power generation equipment, etc. Energy storage converter 20 has a DC side and an AC side. The DC side is used to be electrically connected to battery 10, and the AC side is used to be connected to the power supply source. When battery 10 is charging, energy storage converter 20 acts as a rectifier to convert electrical energy from AC power from the power grid on the AC side to DC power and store it in battery 10. When battery 10 is discharging, energy storage converter 20 acts as an inverter to convert the electrical energy stored in battery 10 from DC power on the DC side to AC power and supply it to the power grid.

[0142] The thermal management system 30 can be used to perform thermal management on components in an energy storage system, including the battery 10 and the energy storage converter 20, such as cooling or heating the battery 10 and cooling the energy storage converter 20. The thermal management system 30 can be connected to the battery 10 and the energy storage converter 20 to achieve thermal management of the battery 10 and the energy storage converter 20.

[0143] The heat exchange medium running in the first heat exchange flow path 31 and the second heat exchange flow path 32 can be a liquid, such as water, water-containing coolant or waterless coolant, but is not limited to liquids, and can also be a gas, solid-liquid mixture or gas-liquid mixture, etc.

[0144] A first pump 311 and a first heat exchanger 312 are disposed in a first heat exchange flow path 31. When started, the first pump 311 drives the heat exchange medium to flow within the first heat exchange flow path 31, and the heat exchange medium exchanges heat with the battery 10 in the first heat exchanger 312. The first heat exchanger 312 can transfer heat to the battery 10 through, but not limited to, thermal conduction. For example, the first heat exchanger 312 may include a cooling plate in contact with the battery 10. The cooling plate can be independent of the battery 10 or can be part of the battery 10, for example, disposed at the bottom of the battery housing or between individual battery cells in a battery module.

[0145] A second pump 321 and a second heat exchanger 322 are disposed in a second heat exchange flow path 32. When started, the second pump 321 drives the heat exchange medium to flow within the second heat exchange flow path 32. The heat exchange medium exchanges heat with the energy storage converter 20 in the second heat exchanger 322. The second heat exchanger 322 can transfer heat to the energy storage converter 20 via, but not limited to, heat conduction. For example, the second heat exchanger 322 may include a cooling plate in contact with the energy storage converter 20. The cooling plate may be independent of the energy storage converter 20 or may be part of the energy storage converter 20.

[0146] The flow path switching mechanism 34 enables operable connection between the first heat exchange flow path 31 and the second heat exchange flow path 32. Through the switching operation of the flow path switching mechanism 34, different heat exchange loop configurations in the thermal management system 30 can be achieved. The flow path switching mechanism 34 can be switched to different switching states to match the working mode of the thermal management system.

[0147] In this embodiment, the first heat exchanger 312 in the first heat exchange path 31 and the second heat exchanger 322 in the second heat exchange path 32 can exchange heat with the battery 10 and the energy storage converter 20 respectively. The first heat exchange path 31 and the second heat exchange path 32 are operably connected through the path switching mechanism 34. According to the control commands issued by the processor 35 to the first pump 311 in the first heat exchange path 31, the second pump 321 in the second heat exchange path 32 and the path switching mechanism 34, the first heat exchange path 31 and the second heat exchange path 32 can each form a loop and operate independently, so as to be independently configured and controlled according to the thermal management requirements of the battery 10 and the energy storage converter 20, thereby meeting more flexible thermal management requirements.

[0148] Referring to Figures 2 and 3, in some embodiments, the flow path switching mechanism 34 includes at least two connected flow paths 33 and a control valve 341. Each of the at least two connected flow paths 33 has its two ends connected to the first heat exchange flow path 31 and the second heat exchange flow path 32, respectively. The control valve 341 is disposed in at least one of the at least two connected flow paths 33 and is configured to switch the on / off state of the connected flow path 33 with the control valve 341. In a first operating mode of the thermal management system 30, both the first pump 311 and the second pump 321 are turned on, and the control valve 341 is switched to the off state to form an independently operating first heat exchange loop and second heat exchange loop. In a second operating mode of the thermal management system 30, the first pump 311 is turned on, the second pump 321 is turned off, and the control valve 341 is switched to the on state to form a combined heat exchange loop driven by the second pump 321 in the second operating mode of the thermal management system 30.

[0149] In the thermal management system 30, multiple connecting flow paths 33 can be connected between the first heat exchange flow path 31 and the second heat exchange flow path 32, and the number can be two or more. A control valve 341 is disposed in at least one of the at least two connecting flow paths 33; that is, the control valve 341 can be disposed in one of the at least two connecting flow paths 33, or in some or all of the at least two connecting flow paths 33.

[0150] The control valve 341 can be located at one or both of the connection ends of the connecting flow path 33 with the first heat exchange flow path 31 and the second heat exchange flow path 32, or it can be located within the connecting flow path 33. The structure of the control valve 341 is not limited, as long as it can switch the flow path 33 on and off; for example, it can be a solenoid valve, a pneumatic valve, or a hydraulic valve. In some embodiments, the control valve 341 can achieve flow control in addition to on / off control.

[0151] In this embodiment, a connecting flow path 33 is provided, connecting the first heat exchange flow path 31 and the second heat exchange flow path 32 at both ends. By controlling the on / off state of the control valve 341, the first heat exchange flow path 31 and the second heat exchange flow path 32 can be easily connected through the connecting flow path 33 to form a loop, or the connecting flow path 33 can be disconnected to achieve independent operation. Combined with the on / off control of the first pump 311 and the second pump 321, the first and second operating modes of the thermal management system 30 can be effectively realized. In the second operating mode, a heat exchange combination loop driven by the second pump 321 is formed, preventing the first pump 311 and the second pump 321 from affecting the independence of the thermal management capabilities achieved by the first heat exchange flow path 31 and the second heat exchange flow path 32 due to the need for flow characteristic matching. Furthermore, single-pump drive can reduce system energy consumption and simplify control complexity.

[0152] Referring to Figure 3, in some embodiments, the at least two connected flow paths 33 include: a first connected flow path 331 and a second connected flow path 332. One end of the first connected flow path 331 is connected to a first position p1 of the first heat exchange flow path 31, and the other end is connected to a second position p2 of the second heat exchange flow path 32. One end of the second connected flow path 332 is connected to a third position p3 of the first heat exchange flow path 31, and the other end is connected to a fourth position p4 of the second heat exchange flow path 32. The second heat exchange flow path 32 includes a first partial heat exchange flow path 323 and a second partial heat exchange flow path 324. One end of the first partial heat exchange flow path 323 is connected to one end of the second partial heat exchange flow path 324 at the second position p2, and the other end of the first partial heat exchange flow path 323 is connected to the other end of the second partial heat exchange flow path 324 at the fourth position p4. The second pump 321 is located within the first partial heat exchange flow path 323, and the heat exchange combination loop includes the first heat exchange flow path 31 and the second partial heat exchange flow path 324.

[0153] The first part of the heat exchange flow path 323 and the second part of the heat exchange flow path 324 of the second connecting flow path 332 can form a second heat exchange circuit under the drive of the second pump 321. At this time, the first connecting flow path 331 and the second connecting flow path 332 can at least partially disconnect the connection between the second heat exchange circuit and the first heat exchange circuit under the action of the control valve 341, so that the two can operate independently.

[0154] The first connecting flow path 331 and the second connecting flow path 332 can both be equipped with control valves 341 to cut off the connection. Alternatively, the first connecting flow path 331 can be cut off by control valve 341 as shown in Figure 3. Even if the second connecting flow path 332 is not disconnected, the second heat exchange circuit and the first heat exchange circuit can still operate independently due to the rapid pressure balance between the first connecting flow path 331 and the second connecting flow path 332.

[0155] In this embodiment, based on the connection relationship between the ends of the first heat exchange flow path 323 and the second heat exchange flow path 324, the second heat exchange flow path 32 is divided into the first heat exchange flow path 323 and the second heat exchange flow path 324 at the second position p2 and the fourth position p4. Thus, when the second pump 321 is turned off, the first heat exchange flow path 323 containing the second pump 321 is also disconnected. In this way, the first heat exchange flow path 31 and the second heat exchange flow path 324 are connected through the first connecting flow path 331 and the second connecting flow path 332 to form a heat exchange combination circuit driven by the first pump 311.

[0156] Referring to Figure 3, in some embodiments, the second heat exchanger 322 is located within the second portion of the heat exchange path 324.

[0157] In this embodiment, the second heat exchanger 322 is disposed in the second heat exchange flow path 324, so that the heat exchange of the energy storage converter 20 can be realized in both the first and second working modes of the thermal management system 30, so as to meet the thermal management requirements of the energy storage converter 20 under different operating conditions.

[0158] Referring to FIG3, in some embodiments, the second heat exchange flow path 32 further includes a natural cooling heat exchanger 325, which is located within the second partial heat exchange flow path 324.

[0159] The natural cooling heat exchanger 325 can utilize the cooling energy from the natural environment to exchange heat with the heat exchange medium passing through it, effectively saving energy consumption. If needed, a fan 327 can be installed near the natural cooling heat exchanger 325 to guide airflow from the environment to exchange heat with it, thereby improving heat exchange efficiency.

[0160] In this embodiment, a natural cooling heat exchanger 325 is provided in the second heat exchange flow path 324. It can participate in the natural heat exchange between the heat exchange medium in the heat management system and the outside in both the first and second working modes of the thermal management system 30, which is beneficial to further reduce system energy consumption.

[0161] Referring to Figure 3, in some embodiments, the natural cooling heat exchanger 325 includes a microchannel heat exchanger 3251.

[0162] Microchannel heat exchangers 3251 typically include a flat tube with multiple microchannels and a manifold connected to the flat tube, wherein the equivalent diameter of the microchannels in the flat tube can be 10-1000 μm. The manifold may contain baffles to divide the heat exchanger's channels into multiple flow paths.

[0163] In this embodiment, the natural cooling heat exchanger 325 adopts a microchannel heat exchanger 3251, which can achieve higher heat exchange efficiency, improve the energy efficiency of the system, and occupy less space.

[0164] Referring to Figure 3, in some embodiments, the second position p2 is located on the outlet side of the second pump 321, and the fourth position p4 is located on the inlet side of the second pump 321; the second heat exchange flow path 32 further includes a one-way valve 326, which is located within the first part of the heat exchange flow path 323 and between the outlet of the second pump 321 and the second position p2; wherein, the one-way valve 326 is configured to unidirectionally flow from the second pump 321 to the second position p2.

[0165] The one-way valve 326 can enable the heat exchange medium to flow unidirectionally from the second pump 321 to the second position p2. This can effectively reduce the backflow of heat exchange medium with high pressure at the outlet side of the second pump 321 back to the second pump 321, which could cause damage to the pump, and is also conducive to maintaining stable system pressure.

[0166] Referring to Figure 3, in some embodiments, the first position p1 is located on the outlet side of the first pump 311, and the third position p3 is located on the inlet side of the first pump 311; the control valve 341 is disposed at the first position p1 and is configured to control the on / off state and flow rate of the first connecting flow path 331.

[0167] The control valve 341 can be a three-way control valve as shown in Figure 3, which can connect and disconnect the first connecting flow path 331 at the first position p1. The connection and disconnection here can include connecting and disconnecting the first connecting flow path 331 itself, and also include connecting and disconnecting the first connecting flow path 331 by opening and closing the connection relationship between the first connecting flow path 331 at the first position p1 and the first heat exchange flow path 31.

[0168] In addition, the control valve 341 can control the opening and closing of the first connecting flow path 331, as well as the flow rate of the first connecting flow path 331. This allows for flow distribution in the heat exchange combination circuit to meet the flow requirements of the first connecting flow path 331 and the second heat exchange flow path 324 for stable operation.

[0169] In this embodiment, the second heat exchange flow path 32 is connected to the inlet and outlet sides of the first pump 311 through the second connecting flow path 332 and the first connecting flow path 331, respectively. The on / off state and flow rate of the first connecting flow path 331 are controlled by the control valve. In addition to meeting the switching needs between the first and second working modes of the thermal management system 30, the flow rate distribution of the branch flow paths in the heat exchange combination loop can also be realized to improve heat exchange efficiency and improve system performance.

[0170] Referring to Figure 3, in some embodiments, the thermal management system 30 further includes an expansion tank 333. The expansion tank 333 is disposed in the second connecting flow path 332, in the first heat exchange flow path 31, near the third position p3, or in the second heat exchange flow path 32, near the fourth position p4.

[0171] Since the first heat exchange flow path 31 and the second heat exchange flow path 32 are connected in the second connecting flow path 332, the expansion tank 333 can be placed in the second connecting flow path 332, in the first heat exchange flow path 31 near the third position p3, or in the second heat exchange flow path 32 near the fourth position p4 to compensate for the volume expansion or contraction of the heat exchange medium in the first heat exchange flow path 31 or the second heat exchange flow path 32 due to temperature changes, and to maintain their pressure stability. This reduces the number of expansion tanks 333 required.

[0172] Figure 4 is a schematic diagram of the structure of the thermal management system according to some other embodiments of the energy storage system of this disclosure. Referring to Figure 4, in some embodiments, the thermal management system 30 further includes a compression refrigeration cycle loop 36. The compression refrigeration cycle loop 36 includes an evaporator 364, a portion of the flow path of the first heat exchange flow path 31 passes through the evaporator 364, and exchanges heat with the compression refrigeration cycle loop 36 through the evaporator 364.

[0173] The compression refrigeration cycle loop 36 enables the circulation of refrigerant fluid, achieving heat transfer through the condensation and evaporation of the refrigerant fluid. The refrigerant may include, but is not limited to, water, ammonia, carbon dioxide, and halogenated hydrocarbon refrigerants. In the compression refrigeration cycle loop 36, the refrigerant operates independently of the heat exchange medium in the first heat exchange path 31, achieving heat transfer through heat exchange.

[0174] A portion of the first heat exchange flow path 31 passes through the evaporator 364, allowing it to exchange heat with the refrigerant flowing through the evaporator 364. This enables the first heat exchange flow path 31 to receive cooling energy from the compression refrigeration cycle loop 36, thereby cooling the flowing heat exchange medium. In Figure 4, dashed lines drawn within the evaporator 364 show the portion of the first heat exchange flow path 31 passing through the evaporator 364, as well as the portion of the compression refrigeration cycle loop 36 passing through the evaporator 364. The evaporator 364 can be a plate heat exchanger evaporator, or other types of evaporators, such as a shell-and-tube evaporator.

[0175] In this embodiment, cooling capacity is provided to the heat exchange medium in the first heat exchange flow path 31 through heat exchange between the compression refrigeration cycle loop 36 and the first heat exchange flow path 31. This improves the thermal management efficiency achieved by the first heat exchange flow path 31 and enhances the configuration flexibility for different thermal management needs. Furthermore, the compression refrigeration cycle loop 36 can achieve high cooling efficiency. By exchanging heat with the first heat exchange flow path 31, it can effectively reduce the temperature of the heat exchange medium flowing in the first heat exchange flow path 31, thereby improving the cooling capacity of the loop containing the first heat exchange flow path 31.

[0176] In Figure 4, the compression refrigeration cycle loop 36 may further include a compressor 361, a condenser 362, a throttling device 363, and a gas-liquid separator 365. The compressor 361 compresses the intake low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant. The condenser 362 cools the high-temperature, high-pressure gaseous refrigerant output from the compressor 361 by releasing heat, at least partially converting it into a liquid state. The throttling device 363 may include a capillary tube, a thermostatic expansion valve, or an electronic expansion valve, which cools and depressurizes the refrigerant output from the condenser 362 by throttling. The evaporator 364 heats the refrigerant passing through the throttling device 363 by absorbing heat, at least partially converting it into a gaseous state. The gas-liquid separator 365 separates the refrigerant output from the evaporator 364 into gas and liquid phases, and inputs the separated low-temperature, low-pressure gaseous refrigerant into the compressor 361.

[0177] Additionally, in Figure 4, the thermal management system 30 may also include a fan 327, which can provide air cooling for the condenser 362 to improve its efficiency. The fan 327 may include axial, centrifugal, or mixed-flow fans. In embodiments where the second heat exchange path 32 also includes a natural cooling heat exchanger 325 located within the second heat exchange path 324, the fan 327 can also guide airflow from the environment to exchange heat with the natural cooling heat exchanger 325, improving heat exchange efficiency and correspondingly reducing the number of fans 327 required, thus reducing costs and energy consumption.

[0178] In this embodiment, the compressor 361 in the compression refrigeration cycle loop 36 can be turned on, off, or have its operating frequency adjusted according to the instructions of the processor 35. In this way, the compressor 361 can be selectively turned on and off to run or stop the compression refrigeration cycle according to the level of thermal management requirements, or the operating frequency of the compressor 361 can be adjusted to generate different levels of cooling capacity. This can more flexibly meet the thermal management requirements of the energy storage system and reduce energy consumption.

[0179] Referring to Figure 4, in some embodiments, a portion of the first heat exchange path 31 passing through the evaporator 364 is located between the first position p1 and the third position p3.

[0180] In Figure 4, the first heat exchange flow path 31 is connected to the first connecting flow path 33 at the first position p1 and to the second connecting flow path 33 at the third position p3. By making part of the flow path of the first heat exchange flow path 31 through the evaporator 364 located between the first position p1 and the third position p3, the heat exchange medium can be split and merged at the first position p1 and the third position p3 when the control valve 341 is connected to the first connecting flow path 331.

[0181] When the first pump 311 is turned on and the second pump 321 is turned off, the heat exchange medium in the first heat exchange flow path 31 is split at the first position p1. One part enters the second part heat exchange flow path 324 through the first connecting flow path 331 and exchanges heat with the energy storage converter 20 through the second heat exchanger 322; the other part enters the evaporator 364 to absorb the cold energy in the compression refrigeration cycle loop 36. The two parts merge at the third position p3 and return to the first heat exchange flow path 31.

[0182] In this embodiment, by positioning a portion of the first heat exchange flow path 31 through the evaporator 364 between the first position p1 and the third position p3, the heat exchange medium of the first heat exchange flow path 31 is diverted to meet the thermal management requirements of the energy storage converter 20, and the cooling effect is improved by absorbing cold energy through the evaporator 364.

[0183] Figure 5 is a schematic diagram of the medium circulation in the thermal management system in the first operating mode of the embodiment shown in Figure 4. In Figure 5, solid arrows indicate the second heat exchange loop operating independently in the first operating mode of the thermal management system, hollow arrows indicate the first heat exchange loop operating independently in the first operating mode of the thermal management system, and linear arrows indicate the operating compression refrigeration cycle loop. Figure 5 also shows, in bold, that the first pump 311, the second pump 321, and the compressor 361 are all in the on state.

[0184] Figure 6 is a schematic diagram of the medium circulation in the second operating mode of the thermal management system in the embodiment shown in Figure 4. In Figure 6, hollow arrows indicate the heat exchange combination circuit of the thermal management system in the second operating mode, and straight arrows indicate the operating compression refrigeration cycle circuit. Figure 6 shows in bold the first pump 311 and compressor 361 in the on state, and in dashed line the second pump 321 in the off state.

[0185] Figure 7 is a schematic diagram of another media circulation in the second operating mode of the thermal management system shown in Figure 4. In Figure 7, hollow arrows indicate the heat exchange combination circuit of the thermal management system operating in the second operating mode. Figure 7 shows the first pump 311 in the on state in bold, and the second pump 321 and compressor 361 in the off state in dashed lines. At this time, the compression refrigeration cycle circuit is in a non-operating state.

[0186] Referring to Figures 5-7, in some embodiments, the thermal management system 30 further includes a processor 35, which is configured to: switch the thermal management system 30 to a first operating mode in response to an ambient temperature being greater than or equal to a first ambient temperature threshold; and switch the thermal management system 30 to a second operating mode in response to an ambient temperature being less than or equal to a second ambient temperature threshold; wherein the first ambient temperature threshold is greater than the second ambient temperature threshold.

[0187] The processor 35 can communicate with the first pump 311, the second pump 321, and the flow path switching mechanism 34 via wired or wireless means to receive data and issue instructions. The processor 35 may include one or more processing units, which can be general-purpose processors, such as CPUs, digital signal processors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components, capable of implementing or executing the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can also be a microprocessor, microcontroller, or any conventional processor.

[0188] Ambient temperature refers to the temperature of the environment in which the thermal management system 30 is located, which can be obtained through temperature detection instruments such as thermometers. The level of ambient temperature can affect the thermal management requirements of both the battery 10 and the energy storage converter 20. The first ambient temperature threshold and the 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 processor 35 can control the flow path switching mechanism 34, the first pump 311, and the second pump 321 to switch to the corresponding operating mode of the thermal management system 30.

[0189] An ambient temperature greater than or equal to a first ambient temperature threshold indicates that the current ambient temperature is relatively high, which to some extent increases the cooling requirements of battery 10 and energy storage converter 20. At this time, the thermal management system 30 is switched to its first operating mode, allowing the first heat exchange circuit and the second heat exchange circuit to operate independently, thereby meeting the cooling requirements of battery 10 and energy storage converter 20 respectively.

[0190] An ambient temperature less than or equal to the second ambient temperature threshold indicates a relatively low current ambient temperature. This reduces the cooling requirements of battery 10 and energy storage converter 20 to some extent, and even necessitates consideration of the heating requirements of battery 10 when the ambient temperature is excessively low. At this time, the thermal management system 30 is switched to its second operating mode, forming a single-pump driven heat exchange combination loop including the first heat exchange flow path 31 and the second partial heat exchange flow path 324. This heat exchange combination loop, driven by the first pump 311, can meet the relatively low cooling requirements of battery 10 and energy storage converter 20. Furthermore, the heat exchange medium after heat exchange with battery 10 can continue to cool the higher-temperature energy storage converter 20, which helps reduce energy consumption.

[0191] 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.

[0192] In this embodiment, the working mode of the thermal management system 30 is switched according to the comparison result of the ambient temperature relative to the threshold, which can effectively meet the different thermal management needs under different ambient temperatures and save energy.

[0193] Referring to Figures 5-7, in some embodiments, the thermal management system 30 further includes a compression refrigeration cycle loop 36. The compression refrigeration cycle loop 36 includes an evaporator 364 and a compressor 361, wherein a portion of the first heat exchange flow path 31 passes through the evaporator 364 and exchanges heat with the compression refrigeration cycle loop 36 through the evaporator 364. The processor 35 is configured to: operate the compressor 361 at a first operating frequency in a first operating mode of the thermal management system 30; and shut down or operate the compressor 361 at a second operating frequency in a second operating mode of the thermal management system 30, wherein the second operating frequency is less than the first operating frequency.

[0194] The processor 35 can be signal-connected to the compressor 361. The compression refrigeration cycle 36 can improve the cooling capacity of the first heat exchange path 31 and other paths connected to it by transferring cooling capacity to the first heat exchange path 31 through the evaporator 364. As mentioned earlier, the ambient temperature can affect the thermal management requirements of the battery 10 and the energy storage converter 20. To enable the thermal management system to meet stronger cooling requirements, when the ambient temperature is greater than or equal to the first ambient temperature threshold, the thermal management system 30 switches to a first operating mode, in which the compressor 361 operates at a higher first operating frequency. This allows the compression refrigeration cycle 36 to transfer more cooling capacity to the first heat exchange path 31, improving cooling efficiency. When the ambient temperature is less than or equal to the second ambient temperature threshold, the thermal management system 30 switches to a second operating mode, in which the compressor 361 is turned off or operates at a lower second operating frequency. Figure 6 shows the state where the compressor 361 operates at a lower second operating frequency, and Figure 7 shows the state where the compressor 361 is turned off. This can reduce or eliminate the energy consumption of the compressor 361.

[0195] In this embodiment, controlling the start-up and shutdown or operating frequency of the compressor according to the working mode of the thermal management system can meet the thermal management requirements under different ambient temperatures and effectively reduce energy consumption.

[0196] Referring to Figures 2 and 5-7, in some embodiments, the flow path switching mechanism 34 includes at least two connected flow paths 33, with each connected flow path 33 having its two ends connected to the first heat exchange flow path 31 and the second heat exchange flow path 32, respectively. The thermal management system 30 also includes a heating mechanism 37, which is disposed in at least one of the at least two connected flow paths 33 and configured to heat the heat exchange medium flowing through the connected flow path 33 where the heating mechanism 37 is located when the heating function is activated. The processor 35 is configured to: disable the heating function of the heating mechanism 37 in a first operating mode of the thermal management system 30; and enable or disable the heating function of the heating mechanism 37 in a second operating mode of the thermal management system 30.

[0197] The processor 35 can be signal-connected to the heating mechanism 37. The heating mechanism 37 can heat the heat exchange medium flowing through its connecting flow path 33 to increase the temperature of the heat exchange medium, making it usable for heating and maintaining the temperature of the battery 10, thus meeting the heating requirements of the battery 10. When the ambient temperature is greater than or equal to the first ambient temperature threshold, the thermal management system 30 switches to a first operating mode, at which time the heating mechanism 37 is turned off, thus saving energy consumption and avoiding the impact of heating on the cooling efficiency of the heat exchange circuit. When the ambient temperature is less than or equal to the second ambient temperature threshold, the thermal management system 30 switches to a second operating mode, at which time the heating mechanism 37 is turned on or off according to the heating or cooling requirements of the battery 10.

[0198] In this embodiment, the opening and closing of the heating mechanism 37 is controlled according to the working mode of the thermal management system, which can meet the thermal management requirements under different ambient temperatures and effectively save energy consumption.

[0199] Figure 8 is a structural schematic diagram of the thermal management system according to some other embodiments of the energy storage system of the present disclosure. Figure 9 is a schematic diagram of the medium circulation of the thermal management system in a first operating mode of the embodiment shown in Figure 8. Figure 10 is a schematic diagram of the medium circulation of the thermal management system in a second operating mode of the embodiment shown in Figure 8. Figure 11 is a schematic diagram of another medium circulation of the thermal management system in a second operating mode of the embodiment shown in Figure 8.

[0200] Referring to Figures 4 and 8, in some embodiments, the at least two connecting flow paths 33 include: a first connecting flow path 331 and a second connecting flow path 332. One end of the first connecting flow path 331 is connected to a first position p1 of the first heat exchange flow path 31, and the other end is connected to a second position p2 of the second heat exchange flow path 32. One end of the second connecting flow path 332 is connected to a third position p3 of the first heat exchange flow path 31, and the other end is connected to a fourth position p4 of the second heat exchange flow path 32. The heating mechanism 37 is disposed in the first connecting flow path 331 or the second connecting flow path 332, and is configured to heat the heat exchange medium flowing through the first connecting flow path 331 or the second connecting flow path 332 where the heating mechanism 37 is located when the heating function is activated.

[0201] In Figures 4-7, the heating mechanism 37 is disposed in the second connecting flow path 332. When its heating function is activated, the heat exchange medium flowing through the second connecting flow path 332 is heated, thereby increasing its temperature. In Figures 8-11, the heating mechanism 37 is disposed in the first connecting flow path 331. When its heating function is activated, the heat exchange medium flowing through the first connecting flow path 331 is heated, thereby increasing its temperature. In other embodiments, the heating mechanism 37 may be disposed in both the first connecting flow path 331 and the second connecting flow path 332.

[0202] When the ambient temperature is high, the thermal management system 30 switches to the first operating mode. Both the battery 10 and the energy storage converter 20 require cooling. In this mode, the heating mechanism 37 does not need to activate its heating function, and no heat exchange medium flows through the second connecting flow path 332 where the heating mechanism 37 is located, or only a small amount of heat exchange medium flows through it before stable circulation. Considering that the flow rate achievable by the heating mechanism 37 may differ from that of the first or second heat exchange loop, placing the heating mechanism 37 in the first or second heat exchange flow path 31 eliminates the risk of flow resistance in either the independently operating first or second heat exchange loop, and also eliminates the need to limit the thermal management capability of the thermal management system to match the allowable flow rate of the heating mechanism 37. Furthermore, it eliminates the risk of surface condensation caused by placing the heating mechanism 37 in the first heat exchange flow path 31, where the heat exchange medium temperature is relatively low, at high ambient temperatures.

[0203] When the ambient temperature is low, the thermal management system 30 switches to the second operating mode, where the battery 10 may require either cooling or heating. During the establishment of the heat exchange combination loop, the heat exchange medium is split and merged at the first position p1 and the third position p3. At this time, a portion of the heat exchange medium flows through the heating mechanism 37, and heating or de-heating is achieved based on the activation and deactivation of the heating function of the heating mechanism 37. Thus, even if the flow rate achievable by the heating mechanism 37 is inconsistent with that of the first heat exchange loop, the risk of flow resistance forming in the heating mechanism 37 can be reduced through flow distribution during the splitting process.

[0204] In Figure 7, when the battery 10 needs to be heated, the heating mechanism 37 is positioned in the second connecting flow path 332, and the heating mechanism 37 is activated. The heat exchange medium, passing through the second part of the heat exchange flow path 324 in the second heat exchange flow path 32, enters the second connecting flow path 332 from the fourth position p4 and its temperature is increased under the heating action of the heating mechanism 37. The heated heat exchange medium enters the first heat exchange flow path 31 and exchanges heat with the battery 10 in the first heat exchanger 312, thereby achieving the heating of the battery 10.

[0205] In Figure 11, when the battery 10 needs to be heated, the heating mechanism 37 is positioned in the first connecting flow path 331, and the heating mechanism 37 is activated. The heat exchange medium passing through the first heat exchanger 312 enters the first connecting flow path 331 from the first position p1 and its temperature increases under the heating action of the heating mechanism 37. Since the temperature of the energy storage converter 20 is higher than that of the battery 10, the heated heat exchange medium can still cool the energy storage converter 20 and absorb its heat after flowing into the second part of the second heat exchange flow path 324. Thus, the heat exchange medium, having absorbed heat from the heating mechanism 37 and the energy storage converter 20, returns to the first heat exchange flow path 31 and exchanges heat with the battery 10 in the first heat exchanger 312, thereby heating the battery 10.

[0206] In this embodiment, by setting the heating mechanism 37 in the first connecting flow path 331 or the second connecting flow path 332, and heating the heat exchange medium flowing through the first connecting flow path 331 or the second connecting flow path 332 where the heating mechanism 37 is located when the heating function is turned on, the heating requirements of the battery 10 can be met.

[0207] Referring to Figures 4-11, in some embodiments, the heating mechanism 37 includes a heater 371. The heater 371 is configured to turn the heating function on or off according to instructions from the processor 35.

[0208] Heater 371 may be an electric heater, a steam heater, or any other available heater. For example, heater 371 may be a safe and efficient positive temperature coefficient (PTC) heater.

[0209] In this embodiment, by heating the heat exchange medium with the heater 371, the temperature of the battery 10 can be increased by the first heat exchanger 312 when the battery 10 temperature is low.

[0210] Referring to Figures 4-11, in some embodiments, the heating mechanism 37 further includes a flow control valve 372 connected in parallel with the heater 371. The flow control valve 372 is configured to control the flow rate of the heat exchange medium passing through the flow control valve 372 according to instructions from the processor 35.

[0211] Considering that there may be a difference between the flow rate of the heat exchange medium in the heat exchange combination loop and the allowable flow rate of the heater 371, which may create flow resistance at the location of the heater 371, the flow distribution can be controlled by using a flow control valve 372 connected in parallel with the heater 371. This can reduce the risk of flow resistance forming in the heater 371, improve the circulation efficiency of the heat exchange medium, and improve the energy efficiency of thermal management.

[0212] The following description, in conjunction with Figures 4-7, illustrates a specific embodiment of the energy storage system.

[0213] The energy storage system includes: a battery 10, an energy storage converter 20, and a thermal management system 30. The thermal management system 30 includes: a first heat exchange flow path 31, a second heat exchange flow path 32, a flow path switching mechanism 34, a processor 35, a compression refrigeration cycle loop 36, and a heating mechanism 37.

[0214] The first heat exchange path 31 includes a first pump 311 and a first heat exchanger 312 for heat exchange with the battery 10, and is configured to form a first heat exchange loop when the first pump 311 is turned on. The second heat exchange path 32 includes a second pump 321 and a second heat exchanger 322 for heat exchange with the energy storage converter 20, and is configured to form a second heat exchange loop when the second pump 321 is turned on.

[0215] The first heat exchange flow path 31 and the second heat exchange flow path 32 are operably connected through the flow path switching mechanism 34. The processor 35 is signal-connected to the flow path switching mechanism 34, the first pump 311, and the second pump 321, and is configured to switch the operating mode of the thermal management system by controlling the opening and closing of the first pump 311 and the second pump 321 and controlling the switching of the flow path switching mechanism 34, so that the first heat exchange loop and the second heat exchange loop can operate independently in the first operating mode of the thermal management system 30, and form a single-pump driven heat exchange combination loop in the second operating mode of the thermal management system 30, the heat exchange combination loop including at least a portion of the flow paths of the first heat exchange loop and the second heat exchange flow path 32.

[0216] The flow path switching mechanism 34 includes a first connecting flow path 331, a second connecting flow path 332, and a control valve 341. One end of the first connecting flow path 331 is connected to a first position p1 of the first heat exchange flow path 31, and the other end is connected to a second position p2 of the second heat exchange flow path 32. One end of the second connecting flow path 332 is connected to a third position p3 of the first heat exchange flow path 31, and the other end is connected to a fourth position p4 of the second heat exchange flow path 32. The second heat exchange flow path 32 includes a first partial heat exchange flow path 323 and a second partial heat exchange flow path 324. One end of the first partial heat exchange flow path 323 is connected to one end of the second partial heat exchange flow path 324 at the second position p2, and the other end of the first partial heat exchange flow path 323 is connected to the other end of the second partial heat exchange flow path 324 at the fourth position p4. The second pump 321 is located within the first partial heat exchange flow path 323. The heat exchange combination circuit includes the first heat exchange flow path 31 and the second partial heat exchange flow path 324.

[0217] The first position p1 is located at the outlet side of the first pump 311, and the third position p3 is located at the inlet side of the first pump 311. The control valve 341 is located at the first position p1 and is configured to control the on / off state and flow rate of the first connecting flow path 331. The processor 35 is configured to turn on both the first pump 311 and the second pump 321 and switch the control valve 341 to the off state in the first operating mode of the thermal management system 30, and to turn on the first pump 311, turn off the second pump 321, and switch the control valve 341 to the on state in the second operating mode of the thermal management system 30.

[0218] The second heat exchanger 322 and the natural cooling heat exchanger 325 are both located within the second portion of the heat exchange flow path 324. The natural cooling heat exchanger 325 includes a microchannel heat exchanger 3251.

[0219] The second position p2 is located at the outlet side of the second pump 321, and the fourth position p4 is located at the inlet side of the second pump 321. The second heat exchange flow path 32 further includes a one-way valve 326, which is located within the first part of the heat exchange flow path 323 and between the outlet of the second pump 321 and the second position p2. The one-way valve 326 is configured to allow unidirectional flow from the second pump 321 to the second position p2.

[0220] The compression refrigeration cycle loop 36 includes a compressor 361, a condenser 362, a throttling device 363, and an evaporator 364. A portion of the flow path of the first heat exchange path 31 passes through the evaporator 364 and exchanges heat with the compression refrigeration cycle loop 36 through the evaporator 364. The portion of the first heat exchange path 31 passing through the evaporator 364 is located between the first position p1 and the third position p3. The compressor 361 is signal-connected to the processor 35 and configured to start, stop, or adjust its operating frequency according to instructions from the processor 35.

[0221] The heating mechanism 37 is disposed in the second connecting flow path 332 and is configured to heat the heat exchange medium flowing through the second connecting flow path 332 where the heating mechanism 37 is located when the heating function is turned on.

[0222] The processor 35 is capable of switching the thermal management system 30 to a first operating mode in response to an ambient temperature greater than or equal to a first ambient temperature threshold. In the first operating mode of the thermal management system 30, the compressor 361 is operated at a first operating frequency, and the heating mechanism 37 is deactivated.

[0223] The processor 35 is also capable of switching the thermal management system 30 to a second operating mode 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. In the second operating mode of the thermal management system 30, the compressor 361 is turned off or operates at a second operating frequency, and the heating mechanism 37 is turned on or off, wherein the second operating frequency is less than the first operating frequency.

[0224] The heating mechanism 37 includes a heater 371 and a flow control valve 372 connected in parallel with the heater 371. The heater 371 is configured to turn the heating function on or off according to the instructions of the processor 35. The flow control valve 372 is configured to control the flow rate of the heat exchange medium passing through the flow control valve 372 according to the instructions of the processor 35.

[0225] Another specific embodiment of the energy storage system will be described below with reference to Figures 8-11.

[0226] The energy storage system includes: a battery 10, an energy storage converter 20, and a thermal management system 30. The thermal management system 30 includes: a first heat exchange flow path 31, a second heat exchange flow path 32, a flow path switching mechanism 34, a processor 35, a compression refrigeration cycle loop 36, and a heating mechanism 37.

[0227] The first heat exchange path 31 includes a first pump 311 and a first heat exchanger 312 for heat exchange with the battery 10, and is configured to form a first heat exchange loop when the first pump 311 is turned on. The second heat exchange path 32 includes a second pump 321 and a second heat exchanger 322 for heat exchange with the energy storage converter 20, and is configured to form a second heat exchange loop when the second pump 321 is turned on.

[0228] The first heat exchange flow path 31 and the second heat exchange flow path 32 are operably connected through the flow path switching mechanism 34. The processor 35 is signal-connected to the flow path switching mechanism 34, the first pump 311, and the second pump 321, and is configured to switch the operating mode of the thermal management system by controlling the opening and closing of the first pump 311 and the second pump 321 and controlling the switching of the flow path switching mechanism 34, so that the first heat exchange loop and the second heat exchange loop can operate independently in the first operating mode of the thermal management system 30, and form a single-pump driven heat exchange combination loop in the second operating mode of the thermal management system 30, the heat exchange combination loop including at least a portion of the flow paths of the first heat exchange loop and the second heat exchange flow path 32.

[0229] The flow path switching mechanism 34 includes a first connecting flow path 331, a second connecting flow path 332, and a control valve 341. One end of the first connecting flow path 331 is connected to a first position p1 of the first heat exchange flow path 31, and the other end is connected to a second position p2 of the second heat exchange flow path 32. One end of the second connecting flow path 332 is connected to a third position p3 of the first heat exchange flow path 31, and the other end is connected to a fourth position p4 of the second heat exchange flow path 32. The second heat exchange flow path 32 includes a first partial heat exchange flow path 323 and a second partial heat exchange flow path 324. One end of the first partial heat exchange flow path 323 is connected to one end of the second partial heat exchange flow path 324 at the second position p2, and the other end of the first partial heat exchange flow path 323 is connected to the other end of the second partial heat exchange flow path 324 at the fourth position p4. The second pump 321 is located within the first partial heat exchange flow path 323. The heat exchange combination circuit includes the first heat exchange flow path 31 and the second partial heat exchange flow path 324.

[0230] The first position p1 is located at the outlet side of the first pump 311, and the third position p3 is located at the inlet side of the first pump 311. The control valve 341 is located at the first position p1 and is configured to control the on / off state and flow rate of the first connecting flow path 331. The processor 35 is configured to turn on both the first pump 311 and the second pump 321 and switch the control valve 341 to the off state in the first operating mode of the thermal management system 30, and to turn on the first pump 311, turn off the second pump 321, and switch the control valve 341 to the on state in the second operating mode of the thermal management system 30.

[0231] The second heat exchanger 322 and the natural cooling heat exchanger 325 are both located within the second portion of the heat exchange flow path 324. The natural cooling heat exchanger 325 includes a microchannel heat exchanger 3251.

[0232] The second position p2 is located at the outlet side of the second pump 321, and the fourth position p4 is located at the inlet side of the second pump 321. The second heat exchange flow path 32 further includes a one-way valve 326, which is located within the first part of the heat exchange flow path 323 and between the outlet of the second pump 321 and the second position p2. The one-way valve 326 is configured to allow unidirectional flow from the second pump 321 to the second position p2.

[0233] The compression refrigeration cycle loop 36 includes a compressor 361, a condenser 362, a throttling device 363, and an evaporator 364. A portion of the flow path of the first heat exchange path 31 passes through the evaporator 364 and exchanges heat with the compression refrigeration cycle loop 36 through the evaporator 364. The portion of the first heat exchange path 31 passing through the evaporator 364 is located between the first position p1 and the third position p3. The compressor 361 is signal-connected to the processor 35 and configured to start, stop, or adjust its operating frequency according to instructions from the processor 35.

[0234] The heating mechanism 37 is disposed in the first connecting flow path 331 and is configured to heat the heat exchange medium flowing through the first connecting flow path 331 where the heating mechanism 37 is located when the heating function is turned on.

[0235] The processor 35 is capable of switching the thermal management system 30 to a first operating mode in response to an ambient temperature greater than or equal to a first ambient temperature threshold. In the first operating mode of the thermal management system 30, the compressor 361 is operated at a first operating frequency, and the heating mechanism 37 is deactivated.

[0236] The processor 35 is also capable of switching the thermal management system 30 to a second operating mode 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. In the second operating mode of the thermal management system 30, the compressor 361 is turned off or operates at a second operating frequency, and the heating mechanism 37 is turned on or off, wherein the second operating frequency is less than the first operating frequency.

[0237] The heating mechanism 37 includes a heater 371 and a flow control valve 372 connected in parallel with the heater 371. The heater 371 is configured to turn the heating function on or off according to the instructions of the processor 35. The flow control valve 372 is configured to control the flow rate of the heat exchange medium passing through the flow control valve 372 according to the instructions of the processor 35.

[0238] 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.

[0239] 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: The battery (10), the energy storage converter (20), and the thermal management system (30), wherein the thermal management system (30) includes: The first heat exchange path (31) includes a first pump (311) and a first heat exchanger (312) for exchanging heat with the battery (10), and is configured to form a first heat exchange loop when the first pump (311) is turned on. The second heat exchange path (32) includes a second pump (321) and a second heat exchanger (322) for heat exchange with the energy storage converter (20), and is configured to form a second heat exchange loop when the second pump (321) is turned on; and A flow path switching mechanism (34) is provided, wherein the first heat exchange flow path (31) and the second heat exchange flow path (32) are operably connected through the flow path switching mechanism (34); The working mode of the thermal management system (30) is switched by opening and closing the first pump (311) and the second pump (321) and switching the flow path switching mechanism (34), so that in the first working mode of the thermal management system (30), the first heat exchange circuit and the second heat exchange circuit operate independently, or in the second working mode of the thermal management system (30), a heat exchange combination circuit is formed, the heat exchange combination circuit including at least part of the flow path of the first heat exchange circuit and the second heat exchange flow path (32).

2. The energy storage system of claim 1, wherein, The flow path switching mechanism (34) includes: At least two connected flow paths (33), each connected flow path (33) having its two ends connected to the first heat exchange flow path (31) and the second heat exchange flow path (32), respectively; and A control valve (341) is disposed in at least one of the at least two connecting flow paths (33) and is configured to switch the on / off state of the connecting flow path (33) in which the control valve (341) is disposed; In the first operating mode of the thermal management system (30), both the first pump (311) and the second pump (321) are turned on, and the control valve (341) is switched to the off state, so as to form an independently operating first heat exchange circuit and second heat exchange circuit; or in the second operating mode of the thermal management system (30), the first pump (311) is turned on, the second pump (321) is turned off, and the control valve (341) is switched to the on state, so as to form a heat exchange combination circuit driven by the second pump (321) in the second operating mode of the thermal management system (30).

3. The energy storage system of claim 2, wherein, The at least two connected flow paths (33) include: The first connecting flow path (331) has one end connected to the first position (p1) of the first heat exchange flow path (31) and the other end connected to the second position (p2) of the second heat exchange flow path (32); and The second connecting flow path (332) is connected at one end to the third position (p3) of the first heat exchange flow path (31) and at the other end to the fourth position (p4) of the second heat exchange flow path (32). The second heat exchange path (32) includes a first heat exchange path (323) and a second heat exchange path (324). One end of the first heat exchange path (323) is connected to one end of the second heat exchange path (324) at the second position (p2). The other end of the first heat exchange path (323) is connected to the other end of the second heat exchange path (324) at the fourth position (p4). The second pump (321) is located in the first heat exchange path (323). The heat exchange combination circuit includes the first heat exchange path (31) and the second heat exchange path (324).

4. The energy storage system of claim 3, wherein, The second heat exchanger (322) is located within the second heat exchange flow path (324).

5. The energy storage system of claim 3 or 4, wherein, The second heat exchange path (32) also includes: The natural cooling heat exchanger (325) is located within the second heat exchange flow path (324).

6. The energy storage system of claim 5, wherein, The natural cooling heat exchanger (325) includes a microchannel heat exchanger (3251).

7. The energy storage system of any of claims 3-6, wherein, The second position (p2) is located on the outlet side of the second pump (321), and the fourth position (p4) is located on the inlet side of the second pump (321); The second heat exchange path (32) also includes: A one-way valve (326) is located in the first part of the heat exchange flow path (323) and between the outlet of the second pump (321) and the second position (p2); The one-way valve (326) is configured to unidirectionally flow from the second pump (321) to the second position (p2).

8. The energy storage system of any of claims 3-6, wherein, The thermal management system (30) also includes: A compression refrigeration cycle loop (36) includes an evaporator (364); Part of the first heat exchange flow path (31) passes through the evaporator (364) and exchanges heat with the compression refrigeration cycle loop (36) through the evaporator (364).

9. The energy storage system of claim 8, wherein, The first heat exchange flow path (31) passes through a portion of the evaporator (364) between the first position (p1) and the third position (p3).

10. The energy storage system of any of claims 3-9, wherein, The first position (p1) is located on the outlet side of the first pump (311), and the third position (p3) is located on the inlet side of the first pump (311); the control valve (341) is located at the first position (p1) and is configured to control the on / off state and flow rate of the first connecting flow path (331).

11. The energy storage system of claim 10, wherein, The thermal management system (30) also includes: An expansion tank (333) is disposed in the second connecting flow path (332), the first heat exchange flow path (31) at a position adjacent to the third position (p3), or in the second heat exchange flow path (32) at a position adjacent to the fourth position (p4).

12. The energy storage system of any of claims 1-11, wherein, The thermal management system (30) further includes a processor (35), which is configured to: In response to an ambient temperature greater than or equal to a first ambient temperature threshold, the thermal management system (30) switches to a first operating mode; and In response to an ambient temperature less than or equal to a second ambient temperature threshold, the thermal management system (30) switches to a second operating mode. Wherein, the first ambient temperature threshold is greater than the second ambient temperature threshold.

13. The energy storage system of claim 12, wherein, The thermal management system (30) also includes: The compression refrigeration cycle loop (36) includes an evaporator (364) and a compressor (361), wherein a portion of the flow path of the first heat exchange flow path (31) passes through the evaporator (364) and exchanges heat with the compression refrigeration cycle loop (36) through the evaporator (364); The processor (35) is configured as follows: In the first operating mode of the thermal management system (30), the compressor (361) is operated at a first operating frequency; and In the second operating mode of the thermal management system (30), the compressor (361) is shut down or operated at a second operating frequency; The second operating frequency is less than the first operating frequency.

14. The energy storage system of claim 12 or 13, wherein, The flow path switching mechanism (34) includes at least two connected flow paths (33), and the two ends of each connected flow path (33) are respectively connected to the first heat exchange flow path (31) and the second heat exchange flow path (32). The thermal management system (30) also includes a heating mechanism (37), which is disposed in at least one of the at least two connected flow paths (33) and is configured to heat the heat exchange medium flowing through the connected flow path (33) where the heating mechanism (37) is located when the heating function is turned on. The processor (35) is configured as follows: In the first operating mode of the thermal management system (30), the heating mechanism (37) is deactivated; and In the second operating mode of the thermal management system (30), the heating mechanism (37) is turned on or off.

15. The energy storage system of claim 14, wherein, The at least two connected flow paths (33) include: The first connecting flow path (331) has one end connected to the first position (p1) of the first heat exchange flow path (31) and the other end connected to the second position (p2) of the second heat exchange flow path (32); and The second connecting flow path (332) is connected at one end to the third position (p3) of the first heat exchange flow path (31) and at the other end to the fourth position (p4) of the second heat exchange flow path (32). The heating mechanism (37) is disposed in the first connecting flow path (331) or the second connecting flow path (332) and is configured to heat the heat exchange medium flowing through the first connecting flow path (331) or the second connecting flow path (332) where the heating mechanism (37) is located when the heating function is turned on.

16. The energy storage system of claim 14 or 15, wherein, The heating mechanism (37) includes: The heater (371) is configured to turn the heating function on or off according to the instructions of the processor (35).

17. The energy storage system of claim 16, wherein, The heating mechanism (37) further includes: A flow control valve (372) is connected in parallel with the heater (371); The flow control valve (372) is configured to control the flow of heat exchange medium through the flow control valve (372) according to instructions of the processor (35).

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