A liquid-cooled energy storage system compatible with oil circulation and static immersion

Abstract

The utility model discloses a kind of liquid cooling energy storage systems compatible with oil circulation and static immersion in the field of energy storage battery refrigeration, including oil cylinder, battery cluster, evaporator heat dissipation component and oil pipe heat dissipation component.Battery cluster contains battery PACK fixed by battery rack, there is sealed side panel in battery rack both sides, and there is hole position in battery PACK bottom.Evaporator heat dissipation component contains evaporator body, air conditioner liquid pipe main pipe and air conditioner gas pipe main pipe;Oil pipe heat dissipation component contains oil outlet pipeline and oil inlet main pipe, and oil outlet pipeline has oil outlet port.Battery rack bottom is sealed to form backflow cavity with oil cylinder, and there is oil extraction member in it, and oil cylinder bottom has oil return interface.The system can switch two kinds of heat dissipation modes, static immersion is used to reduce energy consumption at low power, oil circulation is used to ensure heat dissipation at high power, solve the heat dissipation and temperature uniformity problem under different power, inhibit thermal runaway, improve safety, reduce energy consumption.

Description

Technical Field

[0001] This utility model relates to the field of energy storage battery cooling technology, specifically a liquid-cooled energy storage system compatible with oil circulation and static immersion. Background Technology

[0002] With the ever-increasing demand for energy storage, lithium battery energy storage systems have been widely used in various fields. In these systems, when high-power charging and discharging is required, existing technologies often rely on oil-circulating energy storage systems combined with heat exchangers to achieve heat dissipation. However, this approach has significant drawbacks. During system operation, not only is it necessary to activate the oil pump for circulating heat dissipation, but the limited heat exchange efficiency of the heat exchanger itself also significantly increases the overall energy consumption of the energy storage system. More importantly, this method cannot flexibly adapt to the needs of low-power charging and discharging, resulting in the system's heat dissipation performance and energy consumption failing to reach ideal levels under different power conditions.

[0003] In the relevant technical field, patent application number 2025200437680, entitled "A Battery PACK System Compatible with Static Immersion Liquid Cooling and Flow Cycling," attempts to achieve compatibility between static immersion liquid cooling and flow cycling modes through a specific structural design. However, this patent still has certain shortcomings in terms of accurately matching heat dissipation requirements and controlling temperature uniformity when facing different power charging and discharging. Its heat dissipation mode switching mechanism is not intelligent and efficient enough, and cannot quickly and accurately adjust according to the actual discharge rate of the battery cell. As a result, the heat dissipation effect is difficult to meet the requirements during high-power discharge, thus affecting the battery's performance and lifespan.

[0004] Patent application number 2025200799732, entitled "An Immersion Liquid-Cooled Battery PACK System Compatible with Static and Circulation Pumps," also aims to solve the heat dissipation problem of battery PACK systems. However, in practical applications, this patent has also failed to adequately address the heat dissipation requirements and temperature uniformity issues of the hydraulic cylinder oil circulation energy storage system during charging and discharging at different power levels. During low-power charging and discharging, its energy consumption in static immersion mode is relatively high, failing to fully realize its energy-saving advantages; while during high-power charging and discharging, the operation of the circulation pump cannot effectively guarantee the temperature uniformity between the cells, and the risk of thermal runaway still exists. Utility Model Content

[0005] In order to overcome the shortcomings of existing technical solutions, this utility model provides a liquid-cooled energy storage system that is compatible with oil circulation and static immersion, which can effectively solve the technical problems of the current energy storage battery cooling and heat dissipation methods being inflexible and the difficulty in ensuring temperature uniformity between cells.

[0006] The technical solution adopted by this utility model to solve its technical problem is:

[0007] A liquid-cooled energy storage system compatible with oil circulation and static immersion includes an oil cylinder for containing cooling oil and a battery cluster disposed inside the oil cylinder, as well as an evaporator heat dissipation assembly and an oil pipe heat dissipation assembly.

[0008] The battery cluster includes several battery packs fixed by battery racks. The battery racks have sealed side panels on both sides. The battery packs are composed of arrayed cells. The bottom of the battery packs has multiple holes distributed between adjacent cells.

[0009] The evaporator heat dissipation assembly includes an evaporator body located above each battery pack, a main air conditioning liquid pipe whose output end is connected to the input end of all evaporator bodies, and a main air conditioning gas pipe whose input end is connected to the output end of all evaporator bodies.

[0010] The oil pipe cooling assembly includes an oil outlet pipe located above each evaporator body and an oil inlet main pipe connected to the input end of all oil outlet pipes. The outer side of the oil outlet pipe has multiple oil outlets for discharging cooling oil, and the input end of the oil inlet main pipe is connected to an oil inlet port located on the outside of the oil cylinder.

[0011] The bottom of the battery rack is sealed to the oil cylinder and forms a return cavity that is connected to the inside of the battery PACK. The return cavity is provided with a hollow oil extraction component with an oil return hole. The bottom of the oil cylinder is provided with an oil return interface that is connected to the inside of the oil extraction component.

[0012] Furthermore, the battery pack is fixed longitudinally within the battery rack.

[0013] Furthermore, the input end of the main air conditioning liquid pipe is connected to the air conditioning liquid pipe interface located outside the oil cylinder, and the output end of the main air conditioning gas pipe is connected to the air conditioning gas pipe interface located outside the oil cylinder.

[0014] Furthermore, the evaporator body is composed of several evaporator units arranged above the battery cells. The output end of the main air conditioning liquid pipe is connected to several liquid distributors connected to each battery pack. The liquid distributors are connected to the input ends of all evaporator units of the corresponding battery pack. The output end of the main air conditioning gas pipe is connected to several gas branch pipes connected to each battery pack. The gas branch pipes are connected to the output ends of all evaporator units of the corresponding battery pack.

[0015] Furthermore, the oil outlet pipeline has a U-shaped structure, the main oil inlet pipe is connected to the middle of the oil outlet pipeline, and the oil outlet is distributed along the axial direction of the oil outlet pipeline.

[0016] Furthermore, the oil extraction component has a U-shaped structure, and the oil return holes are distributed on the inner and outer sides of the oil extraction component.

[0017] Compared with the prior art, the beneficial effects of this utility model are:

[0018] By switching between two heat dissipation modes, the heat dissipation requirements of the battery cell at different discharge rates can be met. At low power, the static immersion mode is used to reduce energy consumption, while at high power, the oil circulation mode is used to ensure heat dissipation. This not only effectively solves the heat dissipation requirements and temperature uniformity issues of the oil cylinder oil circulation energy storage system during charging and discharging at different power, but also suppresses the occurrence of thermal runaway, improves the safety of the lithium battery energy storage system, and reduces overall energy consumption. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the internal battery cluster structure of the hydraulic cylinder in an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of the battery cluster connecting the evaporator heat dissipation assembly and the oil pipe heat dissipation assembly according to an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the battery PACK connecting the evaporator body and the oil outlet pipe in an embodiment of this utility model;

[0022] Figure 4 This is a schematic diagram of the evaporator unit structure according to an embodiment of the present invention;

[0023] Figure 5 This is an embodiment of the present utility model. Figure 4 Enlarged schematic diagram of section A in the middle;

[0024] Figure 6 This is a schematic diagram of the bottom structure of the battery cluster in an embodiment of this utility model;

[0025] Figure 7 This is a top-view perspective view of the outer side of the hydraulic cylinder in an embodiment of this utility model;

[0026] Figure 8 This is a three-dimensional view of the outer side of the hydraulic cylinder in an embodiment of the present invention, taken from below.

[0027] Numbering on the map:

[0028] 1-Hydraulic cylinder;

[0029] 101-Oil inlet, 102-Return chamber, 103-Oil extraction component, 104-Oil return interface, 105-Oil return hole, 106-Air conditioning liquid pipe interface, 107-Air conditioning gas pipe interface, 108-Cover plate;

[0030] 2-Battery clusters;

[0031] 21-Battery rack, 22-Battery pack, 23-Side panel;

[0032] 221 - Battery cell, 222 - Hole position;

[0033] 31-Evaporator body, 32-Main main pipe of air conditioning liquid line, 33-Main main pipe of air conditioning gas line, 34-Distributor, 35-Branch pipe of gas line;

[0034] 311 - Evaporator unit, 312 - Evaporator unit input terminal, 313 - Evaporator unit output terminal;

[0035] 41-Outlet oil line, 42-Inlet oil main line;

[0036] 411 - Oil outlet. Detailed Implementation

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0038] like Figure 1-8 As shown, this utility model provides a liquid-cooled energy storage system that is compatible with both oil circulation and static immersion, aiming to solve the heat dissipation adaptability problem of existing lithium battery energy storage systems under different power charging and discharging conditions. By integrating two heat dissipation modes, oil circulation and static immersion, it achieves efficient heat dissipation under low energy consumption.

[0039] The system mainly consists of four parts: oil cylinder 1, battery cluster 2, evaporator heat dissipation assembly, and oil pipe heat dissipation assembly. Each part works in coordination and can flexibly switch the heat dissipation mode according to the discharge rate of battery cell 221.

[0040] The hydraulic cylinder 1 serves as the containment and support structure for the entire system, and is used to hold the cooling oil (i.e., coolant). Its structural design must meet the requirements of sealing and heat dissipation. The hydraulic cylinder 1 is a box structure with an open top, and a removable sealing cover 108 is installed at the opening. The cover 108 and the hydraulic cylinder 1 are sealed with a sealing rubber ring to prevent cooling oil leakage.

[0041] The outer side of the oil cylinder 1 is provided with multiple interfaces, including an oil inlet interface 101, an oil return interface 104, an air conditioning liquid pipe interface 106, and an air conditioning gas pipe interface 107, which are used to connect external equipment such as oil pumps and air conditioning outdoor units.

[0042] Battery cluster 2 is the core component of the energy storage system. It consists of battery rack 21, battery PACK 22 and side panel 23. Its structural design directly affects heat dissipation efficiency and temperature uniformity.

[0043] The battery rack 21, which serves as the mounting carrier for the battery PACK 22, is made of high-strength material. Sealed side panels 23 are fixed to both sides of the rack. These side panels 23 reduce ineffective flow of cooling oil outside the battery rack 21, allowing the cooling oil to flow primarily along the gaps between the battery cells 221, thus improving heat dissipation efficiency.

[0044] The battery pack 22 consists of an array of battery cells 221, with multiple battery packs 22 fixed longitudinally spaced within the battery rack 21. This spaced distribution increases the contact area between the cooling oil and the battery pack 22, while also facilitating the installation of the evaporator body 31 and the oil outlet pipe 41.

[0045] The bottom of the battery PACK22 has multiple holes 222. These holes 222 are distributed between two adjacent cells 221 and are key channels for the flow of cooling oil inside the battery PACK22. They allow the cooling oil to enter the gap between the cells 221 from the bottom, carry away the heat, and then flow upward.

[0046] The evaporator heat dissipation assembly is the main heat dissipation structure in static immersion mode. It achieves heat dissipation through heat exchange between the refrigerant and the cooling oil, and specifically includes:

[0047] The evaporator body 31 is located above each battery PACK 22 and consists of several evaporator units 311. These evaporator units 311 are distributed above the battery cells 221 to maximize contact with the cooling oil. Refrigerant flows inside the evaporator unit 311, absorbing heat from the cooling oil through the evaporation of the refrigerant.

[0048] The air conditioning liquid pipe main pipe 32 has its input end connected to the air conditioning liquid pipe interface 106 on the outside of the oil cylinder 1, and its output end connected to multiple distributors 34. Each distributor 34 corresponds to one of the battery PACK 22. The output port of each distributor 34 needs to be connected to the evaporator unit input end 312 of all evaporator units 311 of the corresponding battery PACK 22 through a pipe, so as to evenly distribute the refrigerant to each evaporator unit 311.

[0049] The output end of the main air conditioning pipe 33 is connected to the air conditioning pipe interface 107 on the outside of the oil cylinder 1, and the input end is connected to multiple pipe branches 35. Each pipe branch 35 corresponds to one of the battery PACK 22. Each pipe branch 35 is connected to the evaporator unit output end 313 of all evaporator units 311 of the corresponding battery PACK 22, which is used to collect the evaporated refrigerant and deliver it to the outdoor unit of the air conditioner for condensation.

[0050] When connected to the outdoor unit of the air conditioner, the air conditioner liquid pipe interface 106 is connected to the refrigerant output end of the outdoor unit of the air conditioner through a pipe, and the air conditioner gas pipe interface 107 is connected to the refrigerant return end of the outdoor unit of the air conditioner through a pipe, forming a closed one-way circulation structure.

[0051] The oil pipe cooling assembly is used to deliver cooling oil to the top of battery PACK22 in oil circulation mode to enhance heat dissipation. Specifically, it includes:

[0052] The oil outlet pipe 41 is located above each evaporator body 31 and has a U-shaped structure. This structure allows the cooling oil to cover the upper area of ​​the battery PACK 22 more evenly. Multiple oil outlets 411 are provided on the outer side of the oil outlet pipe 41. These oil outlets 411 are distributed along the axial direction of the oil outlet pipe 41, which can evenly discharge the cooling oil onto the surface of the battery PACK 22.

[0053] The input end of the main oil inlet pipe 42 is connected to the oil inlet port 101 on the outside of the oil cylinder 1, and the output end is connected to the input end of all oil outlet pipes 41. The middle part of the main oil inlet pipe 42 is connected to the oil outlet pipes 41 to ensure that the oil intake of each oil outlet pipe 41 is uniform.

[0054] To achieve cooling oil circulation, the bottom of the oil cylinder 1 is sealed to the bottom of the battery rack 21, forming a return cavity 102. This cavity is connected to the inside of the battery PACK 22, providing a channel for cooling oil circulation. An oil extraction component 103 is installed within the return cavity 102. The oil extraction component 103 has a U-shaped structure and is hollow inside with multiple return oil holes 105. The return oil holes 105 are distributed on the inner and outer sides of the oil extraction component 103, allowing for uniform oil extraction from different positions within the return cavity 102. An oil return interface 104 is located at the bottom of the oil cylinder 1 and communicates with the inside of the oil extraction component 103. Through the oil return interface 104, cooling oil can be returned to the external oil pump, completing the circulation.

[0055] The core advantage of this system lies in its ability to flexibly switch heat dissipation modes according to the discharge rate of cell 221. The specific working process is as follows:

[0056] (1) Static immersion mode (during low-power charging and discharging)

[0057] When the discharge rate of the battery cell 221 is low, less heat is generated. In this case, only the evaporator cooling assembly needs to be activated, and the oil pump does not need to be started. The cooling oil is statically submerged in the battery cell 221, and the heat generated by the battery cell 221 is transferred to the cooling oil through heat conduction. The low-temperature refrigerant supplied by the outdoor unit of the air conditioner enters the main liquid pipe 32 of the air conditioner through the air conditioner liquid pipe interface 106, and is then distributed to each evaporator unit 311 through the distributor 34. The refrigerant evaporates in the evaporator unit 311, absorbing heat from the cooling oil and lowering the temperature of the cooling oil. The evaporated refrigerant is collected in the main gas pipe 33 of the air conditioner through the gas pipe branch pipe 35, and then returns to the outdoor unit of the air conditioner for condensation through the air conditioner gas pipe interface 107, completing the refrigeration cycle.

[0058] (2) Oil circulation mode (during high-power charging and discharging)

[0059] When the discharge rate of cell 221 is high and the temperature exceeds the set value, the oil pump and evaporator cooling assembly are activated simultaneously to enhance heat dissipation through the circulation of cooling oil. The oil pump pumps cooling oil into the main oil inlet pipe 42 through the oil inlet port 101, and then evenly discharges it above the battery PACK 22 through the oil outlet port 411 of the oil outlet pipe 41. The cooling oil flows downward under gravity, absorbing the heat generated by the cells 221 through the gaps between them, and flows into the return chamber 102 through the hole 222 at the bottom of the battery PACK 22. The cooling oil in the return chamber 102 enters the oil extraction component 103 through the oil return hole 105, and then returns to the oil pump through the oil return port 104, completing the circulation of cooling oil. During this process, the evaporator cooling assembly continues to work, exchanging heat with the refrigerant and the circulating cooling oil to quickly remove heat and significantly improve heat dissipation efficiency. At the same time, the circulation of cooling oil reduces the temperature difference of the cells 221 in vertical height, improving overall temperature uniformity.

[0060] Compared with traditional technologies, this technical solution can meet the heat dissipation requirements of the battery cell at different discharge rates by switching between two heat dissipation modes. At low power, the static immersion mode is used to reduce energy consumption, while at high power, the oil circulation mode is used to ensure heat dissipation. This not only effectively solves the heat dissipation requirements and temperature uniformity issues of the oil cylinder oil circulation energy storage system during charging and discharging at different power, but also suppresses the occurrence of thermal runaway, improves the safety of the lithium battery energy storage system, and reduces overall energy consumption.

[0061] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A liquid-cooled energy storage system compatible with both oil circulation and static immersion, comprising an oil cylinder for containing cooling oil and a battery cluster disposed inside the oil cylinder, characterized in that: It also includes evaporator cooling components and oil pipe cooling components; The battery pack includes several battery packs fixed by a battery rack. The battery rack has sealed side panels on both sides. The battery pack is composed of cells arranged in an array. The bottom of the battery pack has multiple holes distributed between two adjacent cells. The evaporator heat dissipation assembly includes an evaporator body located above each battery pack, an air conditioning liquid main pipe whose output end is connected to the input end of all evaporator bodies, and an air conditioning gas main pipe whose input end is connected to the output end of all evaporator bodies. The oil pipe cooling assembly includes an oil outlet pipe located above each evaporator body and an oil inlet main pipe connected to the input end of all the oil outlet pipes. The outer side of the oil outlet pipe is provided with multiple oil outlets for discharging cooling oil, and the input end of the oil inlet main pipe is connected to an oil inlet port located on the outside of the oil cylinder. The bottom of the battery rack is sealed to the oil cylinder and forms a return cavity that is connected to the inside of the battery PACK. The return cavity is provided with a hollow oil extraction component with an oil return hole. The bottom of the oil cylinder is provided with an oil return interface that is connected to the inside of the oil extraction component.

2. The liquid-cooled energy storage system compatible with oil circulation and static immersion according to claim 1, characterized in that: The battery pack is fixed longitudinally within the battery rack.

3. The liquid-cooled energy storage system compatible with oil circulation and static immersion according to claim 1, characterized in that: The input end of the main air conditioning liquid pipe is connected to the air conditioning liquid pipe interface located outside the oil cylinder, and the output end of the main air conditioning gas pipe is connected to the air conditioning gas pipe interface located outside the oil cylinder.

4. The liquid-cooled energy storage system compatible with oil circulation and static immersion according to claim 1, characterized in that: The evaporator body is composed of several evaporator units that are arranged above the battery cells. The output end of the air conditioning liquid pipe main is connected to several liquid distributors that are connected to each battery pack. The liquid distributors are connected to the input ends of all evaporator units of the corresponding battery pack. The output end of the main air conditioning pipe is connected to several branch pipes that are connected to each battery pack. The branch pipes are connected to the output ends of all evaporator cells of the corresponding battery pack.

5. A liquid-cooled energy storage system compatible with oil circulation and static immersion according to claim 1, characterized in that: The oil outlet pipeline has a U-shaped structure, the main oil inlet pipe is connected to the middle of the oil outlet pipeline, and the oil outlets are distributed along the axial direction of the oil outlet pipeline.

6. A liquid-cooled energy storage system compatible with oil circulation and static immersion according to any one of claims 1-5, characterized in that: The oil extraction component has a U-shaped structure, and the oil return holes are distributed on the inner and outer sides of the oil extraction component.

Images