Solution cooling system for flow battery

Abstract

The utility model belongs to the technical field of flow batteries, and particularly relates to a solution cooling system for a flow battery. The utility model provides a solution cooling system used on a flow battery. A four-way reversing valve, an energy tower, a one-way valve for refrigeration, a parallel refrigerant pump unit and an expansion valve for refrigeration are arranged on a heat exchanger; a parallel compressor unit is arranged on a circulating pipeline of the four-way reversing valve; the refrigeration one-way valve is connected with a heat expansion valve unit in parallel; the mode that the refrigerant pump unit and the expansion valve for refrigeration are connected in parallel and the one-way valve for heating are integrally connected in parallel is adopted, so that 1, the solution cooling system has sufficient and appropriate refrigeration and heating effects; and 2, the structural composition in the solution cooling system is a commercially available product which is relatively easy to obtain, the practicability is high, and the use is simple and convenient.

Description

Technical Field

[0001] The utility model belongs to the technical field of liquid flow batteries, and in particular relates to a solution cooling system used in liquid flow batteries. Background Art

[0002] The structure of a flow battery mainly includes: 1 battery stack, 2 electrolyte tanks, and 2 electrolyte circulation pumps. The battery stack structure can be further divided into an ion membrane and an electrode. The above two electrolytes circulate independently on both sides of the ion membrane, and finally output electrical energy on the electrode.

[0003] Compared with the existing common lithium batteries, the advantages of flow batteries mainly include: large capacity, high safety, long cycle life, and easy capacity adjustment. On the other hand, its disadvantages are also prominent, mainly: large size and heavy weight. Therefore, flow batteries are generally not carried and used. They are mainly applicable to large places such as power stations, enterprises, hospitals, and shopping malls.

[0004] In addition, the normal use of flow batteries also depends on the appropriate electrolyte temperature. If the electrolyte temperature is too high, the electrolyte will be easy to crystallize, and finally reduce the battery performance. If the electrolyte temperature is too low, the electrolyte will solidify, thus affecting its capacity and performance.

[0005] Therefore, existing common liquid flow batteries are generally equipped with an electrolyte temperature control system, namely the above-mentioned solution cooling system. This system is mainly used to cool the electrolyte of the liquid flow battery, and secondly to heat the electrolyte.

[0006] For example, a Chinese utility model patent with authorization announcement number CN216213600U and authorization announcement date 2022.04.05 discloses a heat exchange structure for an all-vanadium liquid flow battery, including: a heat exchanger, which is arranged outside the electrolyte storage tank of the all-vanadium liquid flow battery and connected to the electrolyte storage tank of the all-vanadium liquid flow battery; a first branch pipeline of the power plant's circulating water, which is connected to the heat exchanger and exchanges heat with the electrolyte of the all-vanadium liquid flow battery.

[0007] The heat exchange structure in this utility model patent has the following general structural principles and advantages: utilizing the existing equipment in the power plant, giving full play to the potential of waste heat recovery devices, cooling towers, and water supply systems, reducing the investment and use of new equipment, and eliminating the need to build additional sites and equipment for refrigeration, heat dissipation, circulating pumps, etc.

[0008] However, in actual use, the heat exchange structure still has at least the following two shortcomings, which are also the technical problems to be solved by the present utility model, namely:

[0009] First, there is a lack of sufficient heating effect in the structure;

[0010] Second, the cooling function in this structure depends on the cooling tower equipment in the power plant, so it is relatively restrictive and not very practical.

[0011] Therefore, in summary, there is an urgent need for a new temperature control system with sufficient heating effect and simple and practical cooling effect, so as to perform cooling and heating operations on the electrolyte of the flow battery on demand. Utility Model Content

[0012] The utility model provides a solution cooling system for a liquid flow battery, which can be achieved by arranging a four-way reversing valve, an energy tower, a refrigeration one-way valve, a parallel refrigerant pump unit and a refrigeration expansion valve on a heat exchanger; arranging a parallel compressor unit on a circulation pipeline of the four-way reversing valve; connecting a heat expansion valve unit in parallel to the refrigeration one-way valve; and connecting a heating one-way valve in parallel to the parallel refrigerant pump unit and the refrigeration expansion valve as a whole, so that: 1. the solution cooling system has sufficient and appropriate refrigeration and heating effects; 2. the structural components in the solution cooling system are all relatively easy-to-obtain commercial products, which are highly practical and simple and convenient to use.

[0013] The technical solution adopted by the utility model to solve the above-mentioned problem is: a solution cooling system for a liquid flow battery, the structure of which includes a heat exchanger, a four-way reversing valve, an energy tower, a refrigeration check valve, a parallel refrigerant pump unit and a refrigeration expansion valve which are connected in sequence to form a circulation pipeline, and also includes a parallel compressor unit arranged on the circulation pipeline of the four-way reversing valve, a heating expansion valve unit connected in parallel with the refrigeration check valve, and a heating check valve connected in parallel with the parallel refrigerant pump unit and the refrigeration expansion valve.

[0014] A further preferred technical solution is that the circulation pipeline is connected to the tube side of the heat exchanger, and the electrolyte tank is connected to the shell side of the heat exchanger.

[0015] A further preferred technical solution is that the parallel refrigerant pump unit includes a refrigerant pump and a one-way valve on the pump.

[0016] A further preferred technical solution is that the parallel compressor unit includes a compressor and an on-board one-way valve.

[0017] A further preferred technical solution is that the parallel compressor unit also includes a gas-liquid separator connected in parallel with the on-board one-way valve and located at the air inlet end of the compressor.

[0018] A further preferred technical solution is that the heating expansion valve unit comprises a throttling one-way valve whose forward direction is opposite to that of the cooling one-way valve, and a heating expansion valve.

[0019] A further preferred technical solution is that a liquid storage tank is further provided between the refrigeration one-way valve and the parallel refrigerant pump unit.

[0020] A further preferred technical solution is that insulating flanges are provided between the heat exchanger and the four-way reversing valve, and between the refrigeration expansion valve and the heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the utility model.

[0022] Figure 2 It is a schematic diagram of the connection method of the heat exchanger in the utility model.

[0023] Figure 3 It is a schematic diagram of the position structure of the parallel compressor units in the utility model.

[0024] Figure 4 It is a schematic diagram of the position structure of the parallel refrigerant pump unit in the utility model.

[0025] Figure 5 This is a schematic diagram of the position structure of the heating expansion valve unit in the utility model.

[0026] In the figure, the meanings of the symbols are as follows:

[0027] Electrolyte tank a, battery stack b, electrolyte pump c;

[0028] Heat exchanger 1, four-way reversing valve 2, energy tower 3, refrigeration check valve 4, parallel refrigerant pump unit 5, refrigeration expansion valve 6, parallel compressor unit 7, heating expansion valve unit 8, heating check valve 9, liquid storage tank 10, insulation flange 11;

[0029] Refrigerant pump 501, pump check valve 502, compressor 701, machine check valve 702, gas-liquid separator 703, throttling check valve 801, heating expansion valve 802. DETAILED DESCRIPTION

[0030] The following description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention.

[0031] As attached Figure 1-5 As shown, a solution cooling system for a liquid flow battery comprises a heat exchanger 1, a four-way reversing valve 2, an energy tower 3, a refrigeration check valve 4, a parallel refrigerant pump unit 5 and a refrigeration expansion valve 6 which are sequentially connected to form a circulation pipeline, and also comprises a parallel compressor unit 7 arranged on the circulation pipeline of the four-way reversing valve 2, a heating expansion valve unit 8 connected in parallel with the refrigeration check valve 4, and a heating check valve 9 connected in parallel with the parallel refrigerant pump unit 5 and the refrigeration expansion valve 6.

[0032] In this embodiment, the heat exchanger 1, the four-way reversing valve 2, the energy tower 3, the refrigeration check valve 4, the parallel refrigerant pump unit 5, the refrigeration expansion valve 6, the parallel compressor unit 7, the heating expansion valve unit 8, and the heating check valve 9 are all commercially available products, and the respective methods of use are carried out according to the existing technology.

[0033] Specifically, when the solution cooling system is used to cool the electrolyte, the refrigerant flows in the opposite direction: heat exchanger 1, four-way reversing valve 2, parallel compressor unit 7, back to four-way reversing valve 2, energy tower 3, refrigeration check valve 4, parallel refrigerant pump unit 5, and refrigeration expansion valve 6, and finally back to heat exchanger 1.

[0034] When the solution cooling system is used to heat the electrolyte, the flow direction of the refrigerant is: heat exchanger 1, heating check valve 9, heating expansion valve unit 8, energy tower 3, four-way reversing valve 2, parallel compressor unit 7, then back to the four-way reversing valve 2, and finally back to the heat exchanger 1.

[0035] In addition, if attached Figure 3 As shown, the pipeline between the left valve port and the right vertical center valve port of the four-way reversing valve 2 is the circulation pipeline, and the left valve port must be "in" and the right vertical center valve port must be "out". When the solution cooling system is cooling, the right vertical lower valve port is "in" and the right vertical upper valve port is "out", and the opposite is true when heating.

[0036] In addition, one of the functions of the energy tower 3 is that the solution cooling system cools the refrigerant pipeline with water when cooling. Compared with the traditional air cooling method, the above water cooling method has the advantages that the pipeline is not easy to frost, and no energy is consumed to defrost, so the cooling operation is more efficient.

[0037] The second function of the energy tower 3 is that when the solution cooling system is heating, it can efficiently extract low-grade thermal energy in a low-temperature environment, and realize the transfer of low-grade thermal energy to high-grade thermal energy by inputting a small amount of high-grade energy into the energy tower heat pump unit, thereby heating the refrigerant pipeline. This method consumes energy only when a small amount of high-grade energy is input, and the overall energy consumption is much lower than the traditional electric heating wire heating method.

[0038] On the other hand, the parallel compressor unit 7, the energy tower 3, the refrigeration expansion valve 6, and the heat exchanger 1 correspond to the four most core and indispensable basic steps in the complete refrigeration system, ensuring that the refrigeration effect can be effectively carried out.

[0039] The use of the four-way reversing valve 2 is a necessary condition for the solution cooling system to have both cooling and heating effects.

[0040] Finally, the cooling check valve 4 and the heating expansion valve unit 8 are selectively opened and connected, and the refrigerant flows in opposite directions. The parallel refrigerant pump unit 5 and the cooling expansion valve 6 as a whole are also selectively opened and connected with the heating check valve 9, and the refrigerant flows in opposite directions. Finally, it is ensured that the cooling and heating functions can be selectively and effectively performed.

[0041] The circulation pipeline is connected to the tube side of the heat exchanger 1, and the electrolyte tank a is connected to the shell side of the heat exchanger 1.

[0042] In this embodiment, the structure style of the heat exchanger 1 is: single tube type. The reasons why the electrolyte of the flow battery is connected to the shell side are: first, the shell side volume of the heat exchanger 1 can be used as a supplement to the volume of the electrolyte tank a, thereby improving the capacity and performance of the flow battery; second, refrigerant leakage is more serious than electrolyte leakage, so the former is set in the tube side; third, the relatively small amount of refrigerant in the relatively small volume of the tube side has a sufficient cooling effect at this time.

[0043] Among them, the two material pipes of the heat exchanger 1 are connected to the electrolyte tank a and the battery stack b respectively.

[0044] The parallel refrigerant pump unit 5 includes a refrigerant pump 501 and a one-way valve 502 on the pump.

[0045] In this embodiment, the refrigerant pump 501 and the one-way valve 502 on the pump are selected to be used. When the refrigerant pump 501 is not turned on, the refrigerant all flows through the one-way valve 502 on the pump, and when the refrigerant pump 501 is turned on, the refrigerant all flows through it.

[0046] The parallel compressor unit 7 includes a compressor 701 and an onboard non-return valve 702 .

[0047] In this embodiment, the compressor 701 and the onboard one-way valve 702 are also used selectively.

[0048] Specifically, the combination of the compressor 701 and the refrigerant pump 501 is used as follows:

[0049] When the ambient temperature is greater than 20°C, the compressor 701 is turned on and the refrigerant pump 501 is turned off, and a relatively high-intensity compression refrigeration operation is directly performed;

[0050] When the ambient temperature is between 10°C and 20°C, the compressor 701 and the refrigerant pump 501 are both turned on, and the compressor 701 is of variable frequency type with a wide frequency range, which can adapt to the wide variation of heat load during the electrolyte charging and discharging process;

[0051] When the ambient temperature is less than 10°C, the refrigerant pump 501 is turned on and the compressor 701 is turned off. The refrigeration intensity at this time is relatively low, but it is completely sufficient. More importantly, the power of the refrigerant pump 501 is only about 15% of the power of the compressor 701. Therefore, the energy-saving effect is outstanding in this mode.

[0052] Finally, the solution cooling system uses the above-mentioned "three-speed" modes with different intensities to make the entire refrigeration operation sufficient and appropriate, with outstanding energy-saving advantages.

[0053] The parallel compressor unit 7 further includes a gas-liquid separator 703 which is connected in parallel with the onboard one-way valve 702 and is located at the air inlet end of the compressor 701 .

[0054] In this embodiment, the gas-liquid separator 703 is a commercially available product, and its principle is: to process gas containing a small amount of condensate, to achieve condensate recovery and gas phase purification, to avoid harmful liquid hammer phenomenon in the compressor 701, and it is opened or closed together with the compressor 701.

[0055] The heating expansion valve unit 8 includes a throttling check valve 801 whose forward direction is opposite to that of the cooling check valve 4 , and a heating expansion valve 802 .

[0056] In this embodiment, when the solution cooling system is heating, the specific flow direction of the refrigerant is: heat exchanger 1, heating check valve 9, throttling check valve 801, heating expansion valve 802, energy tower 3, four-way reversing valve 2, on-machine check valve 702, then back to the four-way reversing valve 2, and finally back to the heat exchanger 1.

[0057] At this time, the refrigeration check valve 4, the parallel refrigerant pump unit 5, the refrigeration expansion valve 6, the compressor 701, and the gas-liquid separator 703 are all closed and not used.

[0058] The refrigeration expansion valve 6 is only used in refrigeration, and its function is to expand and evaporate the medium-temperature and high-pressure liquid refrigerant when it passes through, thereby reducing its pressure and temperature and turning it into low-temperature and low-pressure wet steam. The heating expansion valve 802 is only used in heating, and its function is to adjust the flow rate of the refrigerant. The above two have the same structure, and the above two functions are also the basic functions of the expansion valve.

[0059] A liquid storage tank 10 is further provided between the refrigeration check valve 4 and the parallel refrigerant pump unit 5 .

[0060] In this embodiment, the refrigerant used in the solution cooling system may be Freon, and the main refrigerant amount in the entire pipeline is stored in the liquid storage tank 10 and released for use as needed.

[0061] An insulating flange 11 is provided between the heat exchanger 1 and the four-way reversing valve 2 , and between the refrigeration expansion valve 6 and the heat exchanger 1 .

[0062] In this embodiment, the insulating flange 11 is a commercially available product, and its function is: even if the heat exchanger 1 leaks liquid and then accidentally leaks electricity, it will not cause electricity on the pipeline, thereby protecting the on-site operators. Among them, the above-mentioned Freon refrigerant itself is also non-conductive.

[0063] The above is a detailed description of the implementation of the utility model in conjunction with the accompanying drawings, but the utility model is not limited to the above implementation. Various modifications can be made within the knowledge of ordinary technicians in the technical field without departing from the purpose of the utility model. These are all non-creative modifications and are protected by patent law as long as they are within the scope of the claims of the utility model.

Claims

1. A solution cooling system for a flow battery, characterized in that: The structure comprises a heat exchanger (1), a four-way reversing valve (2), an energy tower (3), a refrigeration check valve (4), a parallel refrigerant pump unit (5) and a refrigeration expansion valve (6) which are sequentially connected to form a circulation pipeline, and also comprises a parallel compressor unit (7) arranged on the circulation pipeline of the four-way reversing valve (2), a heating expansion valve unit (8) connected in parallel with the refrigeration check valve (4), and a heating check valve (9) connected in parallel with the parallel refrigerant pump unit (5) and the refrigeration expansion valve (6).

2. A solution cooling system for a liquid flow battery according to claim 1, characterized in that: The circulation pipeline is connected to the tube side of the heat exchanger (1), and the electrolyte tank (a) is connected to the shell side of the heat exchanger (1).

3. A solution cooling system for a liquid flow battery according to claim 1, characterized in that: The parallel refrigerant pump unit (5) comprises a refrigerant pump (501) and a one-way valve (502) on the pump.

4. A solution cooling system for a liquid flow battery according to claim 1, characterized in that: The parallel compressor unit (7) comprises a compressor (701) and an onboard one-way valve (702).

5. A solution cooling system for a liquid flow battery according to claim 4, characterized in that: The parallel compressor unit (7) further comprises a gas-liquid separator (703) connected in parallel with the onboard one-way valve (702) and located at the air inlet end of the compressor (701).

6. A solution cooling system for a liquid flow battery according to claim 1, characterized in that: The heating expansion valve unit (8) comprises a throttling one-way valve (801) having a forward direction opposite to that of the cooling one-way valve (4), and a heating expansion valve (802).

7. A solution cooling system for a liquid flow battery according to claim 1, characterized in that: A liquid storage tank (10) is also provided between the refrigeration one-way valve (4) and the parallel refrigerant pump unit (5).

8. A solution cooling system for a liquid flow battery according to claim 1, characterized in that: Insulating flanges (11) are provided between the heat exchanger (1) and the four-way reversing valve (2), and between the refrigeration expansion valve (6) and the heat exchanger (1).

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