Modularized immersed liquid-cooled energy storage battery thermal management system with inverse opal structure surface

Abstract

A modular immersed liquid-cooled energy storage battery thermal management system with an inverse opal structure surface relates to the field of energy storage battery thermal management, and is characterized in that a cooling liquid supply system feeds a cooling liquid into an immersion bin through a liquid inlet of the immersion bin at the foremost end, and the cooling liquid flows through a heat dissipation structure on the outer side of a battery monomer for heat exchange; and the cooling liquid after heat exchange flows into the next immersion bin through the liquid outlet of the immersion bin, sequentially passes through the immersion bins to exchange heat with the battery monomers, and then flows out from the liquid outlet of the immersion bin at the rearmost end. The heat dissipation structure can increase the heat exchange area with the cooling liquid and improve the heat exchange efficiency of the battery monomers.

Description

Technical Field

[0001] The invention relates to the field of thermal management of energy storage batteries, and in particular to a modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface. Background Art

[0002] my country's energy structure is moving towards clean, low-carbon, safe and efficient, and the proportion of clean energy is steadily increasing. When new energy generation represented by photovoltaic power generation and wind power generation is connected to the grid on a large scale, due to volatility and uncertainty, it brings huge challenges to the stable operation of the power grid. As an important part of the six major links of "collection-generation-transmission-distribution-use-storage" in the operation of the power grid, battery energy storage technology can increase the flexibility of power dispatch, promote peak and frequency regulation of the power grid, and realize rapid emergency power support. On the user side, energy storage technology can also achieve peak shaving and valley filling, rapid response, and improve power quality. It is a key link to ensure the stable operation of the new energy power grid.

[0003] However, while energy storage technology is developing rapidly, it is also accompanied by a series of safety issues. Many energy storage power plants around the world have experienced fire and explosion accidents, and their safety and reliability issues need to be addressed urgently. Battery thermal runaway is the main factor that induces safety problems. The abnormal heating inside the battery and the continuous accumulation of heat cause the temperature to rise sharply, which in turn causes the battery performance to deteriorate, damage, and even explosion. In order to ensure the safety of battery energy storage, a scientific and reasonable battery thermal management system is necessary. Currently, common heat dissipation technologies include air cooling, liquid cooling, phase change cooling, and heat pipe cooling. In the high-rate charging and discharging process of large-scale energy storage battery packs, liquid cooling is more efficient and has more advantages than air cooling. Battery immersion heat dissipation completely immerses the battery in coolant and uses the high thermal conductivity of the coolant to absorb and take away the heat generated by the battery. Two-phase liquid cooling technology is based on the principle of latent heat absorption during the phase change process of the coolant. When the liquid absorbs heat and reaches the boiling point, a phase change occurs. A large amount of heat is carried away through the gas-liquid two-phase flow and the phase change latent heat. Compared with single-phase liquid cooling technology, the heat dissipation coefficient can be increased by 5 to 10 times, which can significantly improve the heat dissipation efficiency and effectively avoid the deterioration of heat dissipation caused by film boiling.

[0004] However, the current immersion liquid cooling system also has defects, such as rapid spread of thermal runaway, inconvenient maintenance, and the "boiling limit" problem under two-phase liquid cooling. When a battery failure continues to overheat, the heat diffusion will corrode the surrounding batteries, causing a chain reaction, and the thermal runaway will continue to spread, causing fires and explosions. When a battery cell in a battery module fails, its disassembly and replacement process is cumbersome, technically demanding, and costly. Therefore, it is necessary to optimize the immersion liquid cooling system to improve the safety and reliability of the battery system and facilitate the disassembly and replacement of faulty batteries. Summary of the invention In order to overcome the deficiencies of the above technologies, the present invention provides a modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface, which improves battery heat dissipation efficiency, prevents the spread of thermal runaway, effectively protects other modules, and improves system safety.

[0005] The technical solution adopted by the present invention to overcome the technical problems is: A modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface, comprising: A plurality of immersion chambers are arranged in the front-to-back direction, each immersion chamber has a closed liquid cooling chamber, a liquid inlet connected to the liquid cooling chamber is provided at the front end of the immersion chamber, and a liquid outlet connected to the liquid cooling chamber is provided at the rear end thereof, and the liquid outlet of the immersion chamber at the front end is connected to the liquid inlet of the immersion chamber at the rear end thereof; A coolant supply system, used for delivering coolant to the liquid cooling chamber of each immersion chamber; A plurality of battery cells, each of which is located in a liquid cooling cavity of a corresponding immersion chamber, is fixed on a bottom plate at the lower end of the immersion chamber, and a heat dissipation structure is arranged around each battery cell.

[0006] In order to prevent thermal runaway and fire spread, the immersion chamber is composed of an outer shell and an inner shell arranged in the outer shell, and a sandwich is formed between the outer shell and the inner shell, and the sandwich is filled with a heat insulation layer.

[0007] Furthermore, the thermal insulation layer is made of porous medium phase change material.

[0008] In order to prevent thermal runaway, the liquid inlet and the liquid outlet are connected to the liquid cooling chamber of the immersion chamber through a temperature control valve.

[0009] Furthermore, it also includes temperature sensors respectively arranged at the front and rear ends of the battery cell, and each temperature sensor and the control end of each temperature control valve are respectively connected to the control unit through wires.

[0010] Furthermore, the above-mentioned coolant supply system is a coolant pump, the liquid inlet of the frontmost immersion chamber is connected to the outlet end of the coolant pump, and the liquid outlet of the rearmost immersion chamber is connected to the inlet end of the coolant pump.

[0011] Furthermore, the bottom plate is provided with a slot matching the battery cell, and the lower end of the battery cell is inserted into the slot and fixed to the bottom plate by adhesive.

[0012] Preferably, the adhesive is epoxy resin or silicone adhesive.

[0013] Furthermore, the heat dissipation structure is composed of a plurality of array ribs with a cross section in the shape of a cross-section connected to each other, and the surface of the array ribs is prepared with an inverse opal structure material.

[0014] In order to reduce the temperature of the battery cell, it also includes rectifier plates located at the four corners of the battery cell. The rectifier plates are fixed to the bottom plate in the vertical direction. The left and right rectifier plates on the front side are symmetrically arranged in an eight-shaped shape, and the left and right rectifier plates on the rear side are symmetrically arranged in an eight-shaped shape. A number of holes are arranged on the rectifier plates.

[0015] The beneficial effects of the present invention are: (1) The modular design is adopted. The battery cells are independently located in separate immersion chambers. The immersion chambers are connected by interfaces, which can effectively control the battery cells and achieve sufficient heat exchange. When a battery cell fails, it is easy to disassemble and repair. At the same time, a temperature sensor is set. The surface temperature sensor of each battery cell detects the temperature of the battery cell in real time and transmits the temperature data to the control unit, which analyzes the temperature data in real time. When the battery temperature is at risk of thermal runaway, the control unit can promptly control the temperature control valves at the inlet and outlet to close, prevent the spread of thermal runaway, effectively protect the remaining modules, and improve system safety.

[0016] (2) The heat dissipation structure of the complex three-dimensional inverse opal structure material prepared on the surface is applied to the battery surface to enhance heat transfer, realizing the active regulation of the heat transfer characteristics of gas-liquid two-phase flow boiling. This heat dissipation structure not only ensures the continuous supply of liquid on the boiling surface, but also maintains stable nucleate boiling under high heat flux conditions, avoiding the transformation of the boiling mode into film boiling. At the same time, the multi-level aperture design of the structure enhances the liquid reflux capacity, reduces the system pressure drop while ensuring heat transfer efficiency, and provides a new technical route for the heat dissipation of large-scale energy storage batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 It is a three-dimensional structural diagram of the battery cell of the present invention; Figure 3 It is a schematic diagram of the top view of the immersion chamber of the present invention; Figure 4 is a schematic diagram of the heat dissipation structure of the present invention; Figure 5 It is a working principle diagram of the heat dissipation structure of the present invention; Figure 6 It is a structural schematic diagram of the rectifier plate of the present invention; In the figure, 1. immersion chamber 2. liquid inlet 3. liquid outlet 4. heat insulation layer 5. wire 6. bottom plate 7. battery cell 8. temperature sensor 9. rectifier plate 10. temperature control valve 11. heat dissipation structure 12. array ribs 101. outer shell 102. inner shell 91. hole. DETAILED DESCRIPTION

[0018] The following is combined with Figure 1 To Attachment Figure 6 The present invention is further described.

[0019] A modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface comprises: a plurality of immersion chambers 1 arranged in a front-to-back direction, each immersion chamber 1 having a closed liquid cooling cavity, a front end of the immersion chamber 1 being provided with a liquid inlet 2 connected to the liquid cooling cavity, a rear end of the immersion chamber 1 being provided with a liquid outlet 3 connected to the liquid cooling cavity, the liquid outlet 3 of the immersion chamber 1 at the front end being connected to the liquid inlet 2 of the immersion chamber 1 at the rear end; a coolant supply system for conveying coolant to the liquid cooling cavity of each immersion chamber 1; and a plurality of battery cells 7, each battery cell 7 being located in the liquid cooling cavity of the corresponding immersion chamber 1, the battery cell 7 being fixed to a bottom plate 6 at the lower end of the immersion chamber 1, and each battery cell 7 being provided with a heat dissipation structure 11 around it. The coolant supply system delivers the coolant into the liquid cooling cavity of the immersion bin 1 through the liquid inlet 2 of the frontmost immersion bin 1, and the coolant flows through the heat dissipation structure 11 outside the battery cell 7 for heat exchange. After the heat exchange, the coolant flows into the liquid cooling cavity of the next immersion bin 1 through the liquid outlet 3 of the immersion bin 1. After passing through each immersion bin 1 and exchanging heat with the battery cell 7 in turn, the coolant flows out from the liquid outlet 3 of the rearmost immersion bin 1. The heat dissipation structure 11 can increase the heat exchange area with the coolant and improve the heat exchange efficiency of the battery cell 7.

[0020] In one embodiment of the present invention, the immersion chamber 1 is composed of an outer shell 101 and an inner shell 102 disposed in the outer shell 101, and a sandwich is formed between the outer shell 101 and the inner shell 102, and the sandwich is filled with a heat insulation layer 4. The heat insulation layer can play a heat insulation and flame retardant role, and can effectively prevent thermal runaway and fire from spreading to the remaining battery cells 7, thereby ensuring the safety of the remaining battery cells 7. The thermal runaway immersion chamber 1 can be replaced in time, which improves the convenience of disassembly and repair of the battery module. In this embodiment, the preferred heat insulation layer is made of a porous medium phase change material.

[0021] In one embodiment of the present invention, the liquid inlet 2 and the liquid outlet 3 are connected to the liquid cooling chamber of the immersion chamber 1 through the temperature control valve 10. It also includes temperature sensors 8 respectively arranged at the front and rear ends of the battery cell 7, and the control ends of each temperature sensor 8 and each temperature control valve 10 are respectively connected to the control unit through a wire 5. The control unit controls the temperature control valve 10 by analyzing the surface temperature of the battery cell 7 detected by the temperature sensor 8. When the surface temperature of the battery cell 7 is abnormal and there is a risk of thermal runaway, the temperature control valve 10 of the liquid inlet 2 and the liquid outlet 3 of the immersion chamber 1 where the battery cell 7 is located is quickly controlled, the liquid inlet 2 and the liquid outlet 3 are closed and an alarm is sounded to prevent the coolant from entering the adjacent immersion chamber 1, affecting other battery cells 7, and preventing the spread of thermal runaway.

[0022] In one embodiment of the present invention, the coolant supply system is a coolant pump, the liquid inlet 2 of the frontmost immersion chamber 1 is connected to the outlet end of the coolant pump, and the liquid outlet 3 of the rearmost immersion chamber 1 is connected to the inlet end of the coolant pump. The coolant pump pumps the coolant from the liquid inlet 2 of the frontmost immersion chamber 1, flows through the liquid cooling cavity of each immersion chamber 1 in turn, exchanges heat with the battery cell 7, and then flows back to the coolant pump through the liquid outlet 3 of the rearmost immersion chamber 1 to achieve circulation.

[0023] In one embodiment of the present invention, a card slot matching the battery cell 7 is provided on the bottom plate 6, and the lower end of the battery cell 7 is inserted into the card slot and fixed to the bottom plate 6 by an adhesive, thereby improving the firmness of the fixation between the battery cell 7 and the bottom plate 6. The adhesive is made of a material with sufficient adhesion, good insulation, corrosion resistance and high temperature resistance, and preferably, the adhesive is an epoxy resin or a silicone adhesive.

[0024] In one embodiment of the present invention, the heat dissipation structure 11 is composed of a plurality of array ribs 12 with a cross-section in the shape of a "J" connected to each other, and the surface of the array ribs 12 is prepared with an inverse opal structure material. The surface of the battery cell 7 is provided with regularly arranged surface array ribs 12, and the heat dissipation structure of the inverse opal structure material is processed on the ribs on the surface of the battery cell 7 and the grooves formed therebetween by the template method. The structure forms a three-dimensional complex porous network structure with a regular arrangement by self-assembling a colloidal crystal template, then depositing the target material, and finally removing the template to achieve micro-nanoscale heat transfer enhancement. The array ribs 12 in the shape of a "J" increase the heat exchange area, and the inverse opal structure material promotes heat exchange through a unique multi-scale pore network. When the coolant flows through the inverse opal structure material, the bottom micropores provide capillary force to continuously pull and replenish the liquid, and the upper macropores provide an overflow channel for the bubbles to form a stable microscale liquid film, which effectively prevents local drying and maintains an efficient nucleate boiling heat exchange process.

[0025] In one embodiment of the present invention, it also includes rectifier plates 9 located at the four corners of the battery cell 7, which are fixed on the bottom plate 6 in the vertical direction. The two left and right rectifier plates 9 on the front side are symmetrically arranged in an eight-shaped shape, and the two left and right rectifier plates 9 on the rear side are symmetrically arranged in an eight-shaped shape. The rectifier plates 9 are provided with a plurality of holes 91. The coolant flows in through the liquid inlet 2 of the first immersion chamber 1, and most of the coolant impacts the surface of the battery cell 7 through the rectifying effect of the two eight-shaped rectifier plates 9 at the front end of the battery cell 7. After flowing through the entire battery cell 7, the coolant flows more through the back of the battery cell 7 through the rectifying effect of the two eight-shaped rectifier plates at the rear end of the battery cell 7, and finally flows out through the liquid outlet 3, and flows into the next immersion chamber 1 from the liquid inlet 2 of the next immersion chamber 1. In this way, it flows through each immersion chamber 1 to achieve convection heat exchange with the battery cell 7 and reduce the temperature of the battery cell 7. When the coolant flows through each immersion chamber 1, while ensuring the rectifying effect of the rectifying plate 9, the holes 91 of the bionic honeycomb structure penetrating the surface of the rectifying plate 9 can effectively reduce the impact of the coolant on the rectifying plate 9, thereby reducing the coolant pump work and energy consumption. At the same time, it can reduce the coolant flow rate loss and better maintain the original flow shape.

[0026] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface, characterized in that: include: A plurality of immersion chambers (1) are arranged in a front-to-back direction, each immersion chamber (1) having a closed liquid cooling chamber therein, a liquid inlet (2) connected to the liquid cooling chamber being provided at the front end of the immersion chamber (1), and a liquid outlet (3) connected to the liquid cooling chamber being provided at the rear end thereof, the liquid outlet (3) of the immersion chamber (1) at the front end being connected to the liquid inlet (2) of the immersion chamber (1) at the rear end thereof; A coolant supply system, used for conveying coolant to the liquid cooling chamber of each immersion chamber (1); A plurality of battery cells (7), each battery cell (7) being located in a liquid cooling cavity of a corresponding immersion chamber (1), the battery cell (7) being fixed on a bottom plate (6) at the lower end of the immersion chamber (1), and a heat dissipation structure (11) being arranged around each battery cell (7).

2. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 1, characterized in that: The immersion chamber (1) is composed of an outer shell (101) and an inner shell (102) arranged in the outer shell (101); a sandwich is formed between the outer shell (101) and the inner shell (102); and a heat insulation layer (4) is filled in the sandwich.

3. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 2, characterized in that: The heat insulation layer (4) is made of a porous medium phase change material.

4. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 1, characterized in that: The liquid inlet (2) and the liquid outlet (3) are both connected to the liquid cooling chamber of the immersion chamber (1) via a temperature control valve (10).

5. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 4, characterized in that: It also includes temperature sensors (8) respectively arranged at the front and rear ends of the battery cell (7), and the control ends of each temperature sensor (8) and each temperature control valve (10) are respectively connected to the control unit via a wire (5).

6. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 1, characterized in that: The coolant supply system is a coolant pump, wherein the liquid inlet (2) of the frontmost immersion chamber (1) is connected to the outlet of the coolant pump, and the liquid outlet (3) of the rearmost immersion chamber (1) is connected to the inlet of the coolant pump.

7. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 1, characterized in that: The bottom plate (6) is provided with a slot matching the battery cell (7); the lower end of the battery cell (7) is inserted into the slot and is bonded and fixed to the bottom plate (6) by an adhesive.

8. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 7, characterized in that: The adhesive is epoxy resin or silicone adhesive.

9. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 1, characterized in that: The heat dissipation structure (11) is composed of a plurality of array ribs (12) having a cross-section in the shape of an "X" connected to each other, and the surface of the array ribs (12) is prepared with an inverse opal structure material.

10. The modular immersion liquid-cooled energy storage battery thermal management system with an inverse opal structure surface according to claim 1, characterized in that: It also includes rectifier plates (9) respectively located at the four corners of the battery cell (7), the rectifier plates (9) being fixed on the bottom plate (6) in the vertical direction, the two rectifier plates (9) on the front side being symmetrically arranged in an eight-shaped shape, and the two rectifier plates (9) on the rear side being symmetrically arranged in an eight-shaped shape, and the rectifier plates (9) are provided with a plurality of holes (91).

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