Refrigerating method of all-vanadium liquid flow energy storage refrigerating system

Abstract

The invention relates to the technical field of energy storage and refrigeration, in particular to a refrigeration method of an all-vanadium redox flow energy storage refrigeration system.The all-vanadium redox flow energy storage refrigeration system comprises an all-vanadium redox flow energy storage unit used for achieving storage and release of electric energy, and a heat management system of the all-vanadium redox flow energy storage refrigeration system can collect heat generated by an electric pile; a heat dissipation and heating device is arranged to ensure that the electric pile runs at a proper temperature; the refrigerating unit is an absorption type refrigerating unit and is used for refrigerating by using the heat collected by the all-vanadium liquid flow energy storage unit through the heat management system and the industrial waste heat as heat sources; the system further comprises an energy coupling and integrating device. The control system is connected with the monitoring unit, and the auxiliary device is connected with the safety system. Through a heat management system of the all-vanadium redox flow energy storage system, heat generated by the electric pile is reasonably collected and utilized, meanwhile, industrial waste heat is utilized for heating the electric pile at the low temperature, extra energy consumption is reduced, the heat management system is combined with waste heat of a steel mill to drive an absorption type refrigeration unit, and efficient recycling of the waste heat is achieved.

Description

Technical Field

[0001] This invention relates to the field of energy storage and refrigeration technology, and in particular to a refrigeration method for a full vanadium redox flow energy storage and refrigeration system. Background Art

[0002] In current industrial production, many scenarios have a continuous demand for cooling, such as control rooms in steel plants, cooling of electrical equipment, and compressed air pretreatment. Traditional cooling methods mostly rely on electricity, resulting in high energy consumption and underutilization of waste heat resources generated in industrial production. Furthermore, power grid supply varies between peak and off-peak hours, with high costs for industrial electricity during peak periods and power supply stability affected by grid fluctuations. Absorption refrigeration units can utilize low-grade waste heat for stable operation, but they are highly sensitive to heat source temperatures, and their efficiency drops significantly when the heat source temperature is insufficient. Industrial sites such as steel plants are rich in waste heat resources, such as blast furnace / converter gas, flue gas, and steam, with temperatures ranging from 50-300℃. While self-owned power plants can provide stable electricity (although there are peak and off-peak fluctuations), the waste heat quality is dispersed (mixed high and low temperatures, making recovery difficult), and the power load fluctuates greatly (affecting the stability of the cooling system). Moreover, traditional cooling equipment has low energy efficiency (e.g., cooling towers are energy-intensive and affected by ambient temperature). Therefore, how to construct a system that combines industrial waste heat with energy storage technology to achieve efficient cooling has become an urgent problem to be solved. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a full vanadium redox flow energy storage and refrigeration system and refrigeration method to address the above-mentioned technical deficiencies, thereby solving the problem of how to construct a system that can combine industrial waste heat and energy storage technology to achieve efficient refrigeration.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a full vanadium redox flow energy storage and refrigeration system, comprising: a full vanadium redox flow energy storage unit for storing and releasing electrical energy, wherein its thermal management system can collect the heat generated by the fuel cell stack, and is equipped with heat dissipation and heating devices to ensure that the fuel cell stack operates at a suitable temperature. The refrigeration unit is an absorption refrigeration unit, which uses the heat collected by the vanadium redox flow storage unit through the thermal management system and industrial waste heat as a heat source for refrigeration. The energy coupling and integration device includes an electric coupling component and a thermal coupling component, which respectively realize the electric and thermal interaction between the vanadium redox flow storage unit and the refrigeration unit. The thermal coupling component can introduce industrial waste heat into the thermal management system for stack heating. The control and monitoring unit is used to coordinate the operation of the vanadium redox flow storage unit and the refrigeration unit, and to monitor the parameters of each system. Auxiliary equipment and safety systems are used to ensure the stable and safe operation of the system.

[0005] This technical solution has been further optimized, and the all-vanadium redox flow storage unit includes a stack system, an electrolyte circulation system, and a thermal management system; The fuel cell stack system uses porous material electrode components, ion exchange membranes, and flow field plates to achieve the conversion of electrical energy into chemical energy; The electrolyte circulation system maintains electrolyte circulation through positive and negative electrolyte storage tanks, circulation pumps, and pipeline valves; The thermal management system uses an electric stack heat exchanger, temperature sensors, heat collection and dissipation devices, and a heating path connected to industrial waste heat to control the electrolyte temperature.

[0006] To further optimize this technical solution, when the thermal management system is operating normally and needs to collect heat, it will transfer the heat to the heat storage tank through the set heat exchanger network; when there is excess heat or the fuel cell stack temperature is too high, the cooling fan / cooling tower will be activated to dissipate heat; when starting at low temperature or when the ambient temperature is too low, industrial waste heat will be introduced through the heat exchanger network to heat the fuel cell stack. To further optimize this technical solution, the refrigeration unit uses lithium bromide-water as the working fluid pair and consists of a generator, condenser, throttling device, evaporator and absorber. The generator receives the mixed heat source and drives the refrigeration cycle. The mixed heat source is formed by mixing the heat collected by the vanadium redox flow storage unit with industrial waste heat and then heating it up. The temperature range is 60-80℃.

[0007] To further optimize this technical solution, the power coupling component in the energy coupling and integration device achieves power interaction with the controller through the converter and distribution box, and the converter has bidirectional conversion function; The thermal coupling component uses a heat exchanger network and a heat storage tank to mix the heat collected by the energy storage stack with industrial waste heat, and then raises the temperature through an industrial waste heat recovery device, which uses an organic Rankine cycle preheater.

[0008] To further optimize this technical solution, the control system and monitoring unit includes a central controller and sensors and monitoring equipment. The central controller coordinates the operation of the energy storage and cooling system, controls the charging and discharging and cooling power according to the electricity price, load and cooling demand, and controls the transfer of industrial waste heat to the stack at low temperatures. The sensors and monitoring equipment monitor parameters such as power, cooling capacity and temperature.

[0009] To further optimize this technical solution, the auxiliary equipment and safety system include a liquid replenishment device, a filtration system, a gas detector, a fire extinguishing device, and a pressure relief valve; the liquid replenishment device is used to replenish the electrolyte and refrigerant, the filtration system is used to purify the electrolyte, and the gas detector, fire extinguishing device, and pressure relief valve are used to ensure system safety.

[0010] The present invention also provides a cooling method for a vanadium redox flow energy storage cooling system, comprising the following steps: controlling the vanadium redox flow energy storage unit to charge and discharge, its thermal management system collecting the heat generated by the stack to the heat storage tank according to the stack temperature, or starting heat dissipation when the temperature is too high, and introducing industrial waste heat to heat the stack when starting at low temperature or when the ambient temperature is too low, so as to ensure the normal operation of the stack. Collect industrial waste heat, mix the heat collected by the vanadium redox flow storage unit with the industrial waste heat and raise the temperature, and use it as a heat source for the absorption refrigeration unit. The absorption refrigeration unit is activated to utilize the heat source for cooling, thereby meeting the cooling load requirements. The control system monitors the parameters of each system in real time and adjusts the operating status according to the set strategy to ensure the stable and safe operation of the system.

[0011] To further optimize this technical solution, the vanadium redox flow storage unit is charged during off-peak hours and discharged during peak hours or when cooling load demand increases, thus providing power support for the refrigeration system.

[0012] To further optimize this technical solution, the working mode of the thermal management system of the vanadium redox flow storage unit is dynamically adjusted according to seasonal and ambient temperature changes, optimizing the switching timing of heat collection, heat dissipation and industrial waste heat heating, thereby improving energy utilization efficiency.

[0013] Compared with existing technologies, this invention has the following advantages: 1. Through the thermal management system of the vanadium redox flow storage system, the heat generated by the fuel cell stack is rationally collected and utilized. At the same time, industrial waste heat is used to heat the fuel cell stack at low temperatures, reducing additional energy consumption. Combined with the waste heat from the steel plant to drive the absorption refrigeration unit, efficient recovery and utilization of waste heat is achieved, increasing the overall energy utilization efficiency from 30% (waste heat waste + high energy consumption of electric refrigeration) in the traditional mode to over 65%; 2. In terms of electricity costs, the peak-valley arbitrage function of the energy storage system is utilized, and no electric heater is required, saving approximately RMB 120,000-220,000 per MWh of energy storage capacity per year. In terms of refrigeration costs, absorption refrigeration saves 70% more electricity than electric refrigeration. Combined with waste heat utilization, the cost of cooling capacity is reduced to below RMB 0.14 per kWh; 3. The thermal management system of the vanadium redox flow storage system ensures the stable operation of the fuel cell stack by coordinating heat collection, heat dissipation and industrial waste heat heating. The energy storage system smooths out the power load fluctuations of the steel plant and provides stable power to the refrigeration system. The refrigeration system's heat source has been changed from a single waste heat source to a dual guarantee of waste heat + energy storage and heat collection, reducing the failure rate by 50% and improving the overall operational stability of the system. At the same time, the multi-scenario utilization of industrial waste heat has also improved the system's energy adaptability. Attached Figure Description

[0014] Figure 1 A schematic diagram of a vanadium redox flow energy storage and refrigeration system; Figure 2 This is a schematic diagram of the external structure of the fuel cell stack.

[0015] 1. Fuel cell stack; 11. Electrolyte piping; 2. Fuel cell heat exchanger; 20. Heat dissipation fins; 21. Coolant connection port. DETAILED DESCRIPTION

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0017] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains. Terms such as “up,” “down,” “left,” and “right” are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0018] Example 1

[0019] Combination Figure 1 As shown, a vanadium redox flow energy storage and refrigeration system includes: a vanadium redox flow energy storage unit, a refrigeration unit, an energy coupling and integration device, a control system and monitoring unit, and auxiliary equipment and a safety system.

[0020] The vanadium redox flow storage unit includes a stack system, an electrolyte circulation system, and a thermal management system.

[0021] In the fuel cell stack system, porous electrode components made of porous materials such as carbon felt and graphite felt are used to provide a site for electrochemical reactions. Ion exchange membranes separate the positive and negative electrode electrolytes, preventing ion mixing while allowing hydrogen ions to pass through to maintain charge balance. Flow field plates guide the electrolyte to flow uniformly across the electrode surface, ensuring reaction efficiency. Thus, the conversion of electrical energy into chemical energy is achieved through the ion exchange membrane and flow field plates.

[0022] The electrolyte circulation system includes a positive electrolyte storage tank and a negative electrolyte storage tank, which store electrolytes containing V, respectively. 3 + / V 4+ (Positive electrode) and V 2+ / V 3+The electrolyte solution (negative electrode) is a sulfuric acid solution. A circulation pump drives the electrolyte circulation within fuel cell stack 1. This circulation pump can be a magnetic pump or a centrifugal pump to prevent electrolyte leakage. The electrolyte flow rate and direction can be controlled using pipes and valves, including check valves and shut-off valves. The electrolyte circulation system maintains electrolyte circulation through positive and negative electrode electrolyte storage tanks, the circulation pump, pipes, and valves. The electrolyte circulation system provides electrolyte to the fuel cell stack system.

[0023] The thermal management system is equipped with a heat exchange network and a heat dissipation and heating device. The heat exchange network is equipped with an electric stack heat exchanger 2, and the heat exchange network is connected to the electric stack system for heat exchange through the electric stack heat exchanger 2.

[0024] Combination Figure 2 As shown, each fuel cell stack 1 has a set of fuel cell heat exchangers 2 on both sides. The interior of the fuel cell heat exchanger 2 is a hollow structure, and the outer side is equipped with heat dissipation fins 20. The cavity of the fuel cell heat exchanger 2 is filled with coolant. Multiple sets of electrolyte pipes 11 are spirally threaded inside the fuel cell heat exchanger 2. The electrolyte entering and leaving the fuel cell stack 1 first passes through the corresponding electrolyte pipes 11 and then connects to the electrolyte storage tank. The electrolyte pipes 11 are made of thermally conductive insulating material. The internal cavity of the fuel cell heat exchanger 2 is equipped with a coolant connection port 21. The coolant inside the fuel cell heat exchanger 2 is connected to the heat exchange network through the coolant connection port 21, and finally the heat generated by the operation of the fuel cell stack is transferred to the heat storage tank for heat storage. At the same time, the operating temperature of the corresponding fuel cell stack 1 can also be adjusted by adjusting the circulation flow rate and temperature of the coolant to ensure that the fuel cell stack 1 operates within a suitable temperature range.

[0025] Specifically, the heat exchanger 2 of the fuel cell stack utilizes a coolant (such as water or ethylene glycol solution) to exchange heat with the electrolyte. During normal operation and when heat collection is required, the heat is transferred to the heat storage tank through the heat exchanger network to collect heat in the fuel cell stack system. When there is excess heat or the temperature of the fuel cell stack 1 is too high, the cooling fan / cooling tower in the heat dissipation and heating device is activated. The cooling fan / cooling tower, as a supplementary heat dissipation device for the fuel cell stack 1, can promptly cool the system and prevent the heat storage tank from becoming saturated or the system temperature from becoming too high during maintenance. When starting at low temperatures or when the ambient temperature is too low, industrial waste heat is introduced through the heating device in the heat dissipation and heating device to heat the fuel cell stack 1 through heat exchange, ensuring that the fuel cell stack 1 operates within a suitable temperature range. Temperature sensors are arranged in the heat exchanger 2 to indirectly monitor changes in electrolyte temperature. The temperature signals provided by the temperature sensors can be used to control the opening or closing of the aforementioned heat dissipation and heating devices. The thermal management system uses the fuel cell stack heat exchanger 2, temperature sensors, heat storage tank, and heat dissipation and heating devices in the heat exchange network to control the electrolyte temperature. The heat exchange network is also connected to industrial waste heat through a heating path.

[0026] The aforementioned vanadium redox flow storage unit is used to store and release electrical energy. Its thermal management system can collect the heat generated by the fuel cell stack 1 and is equipped with heat dissipation and heating devices to ensure that the fuel cell stack 1 operates at a suitable temperature. When the thermal management system is operating normally and needs to collect heat, it transfers the heat to the heat storage tank through a heat exchanger network. When there is excess heat or the temperature of the fuel cell stack 1 is too high, the cooling fan / cooling tower is activated to dissipate heat. When starting at low temperature or when the ambient temperature is too low, industrial waste heat is introduced through the heat exchanger network to heat the fuel cell stack 1.

[0027] The refrigeration unit uses lithium bromide-water as the working fluid pair, with water as the refrigerant. The unit consists of a generator, condenser, throttling device, evaporator, and absorber. The refrigeration principle here is similar to that of existing absorption refrigeration units.

[0028] The generator receives a mixed heat source and drives a refrigeration cycle. Specifically, the generator utilizes heat collected and stored in a storage tank by a vanadium redox flow storage unit via a thermal management system, along with waste heat from the steel plant, as a heat source. This heat source causes water in the lithium bromide solution to evaporate, forming high-temperature, high-pressure water vapor. The condenser cools and liquefies the water vapor, releasing heat to form relatively high-pressure liquid refrigerant water. A throttling device reduces the pressure of the refrigerant water within the refrigeration unit through an expansion valve, transforming it into relatively low-temperature, low-pressure liquid water. In the evaporator, the low-temperature refrigerant liquid evaporates and absorbs heat, providing cooling for end-user industrial processes, such as cooling air or water.

[0029] Finally, the refrigerant reforms into water vapor, which is then sent to the absorber for reabsorption. The absorber contains a concentrated lithium bromide solution, which is returned from the generator after concentration. The diluted lithium bromide solution is then sent back to the generator for the next cycle. This absorption refrigeration unit utilizes heat collected by the vanadium redox flow storage unit via a thermal management system and industrial waste heat as a heat source for refrigeration.

[0030] The energy coupling and integration device in the system includes a power coupling component and a thermal coupling component, which respectively realize the power interaction and heat interaction between the vanadium redox flow storage unit and the cooling unit. Details of the power interaction are described below. The thermal coupling component can introduce industrial waste heat into the thermal management system for heating the fuel cell stack system. The power coupling component achieves power interaction with the central controller through a converter and a distribution box. The converter converts the DC power from the vanadium redox flow storage unit into AC power, and the converter has bidirectional conversion capabilities to drive the cooling unit and other power-requiring equipment within the overall system. The distribution box and the central controller manage power distribution and coordinate the charging and discharging of the vanadium redox flow storage unit and the start / stop of the cooling unit. Based on grid electricity prices and load demand, the central controller controls the vanadium redox flow storage unit to charge during off-peak hours and discharge during peak hours to power the cooling unit, reducing electricity costs. In the overall system, the heat exchanger network uses thermal coupling components to mix the heat stored in the heat storage tank with industrial waste heat, raising the temperature of the mixed heat source supplied to the refrigeration unit. Due to the inherent characteristics of industrial waste heat, such as insufficient temperature and poor stability, the temperature and flow rate fluctuate with production conditions. The industrial waste heat recovery device employs an organic Rankine cycle preheater. This preheater, through the phase change cycle of a low-boiling-point organic working fluid, can stably raise the mixed heat source (50-65℃) to 60-80℃. For example, mixed waste heat at 55℃ enters the preheater, and through the working fluid's heat absorption-expansion-release process, outputs a heat source at 70℃, precisely meeting the temperature requirements of the lithium bromide generator. The heat collected by the vanadium redox flow stack 1 is generally at a temperature of 40-60℃, while waste heat from steel plants, such as blast furnace cooling water, has a temperature of 50-90℃. The industrial waste heat recovery device raises the mixed heat source temperature to 60-80℃, meeting the hot-end temperature requirements of the generator in the absorption refrigeration unit. Setting up thermal storage tanks can also temporarily store excess heat and balance the time difference between supply and demand. At the same time, when the ambient temperature is too low, some industrial waste heat can be introduced into the thermal management system through the heat exchanger network for heating the fuel cell stack 1 of the vanadium redox flow storage unit.

[0031] The control system and monitoring unit includes a central controller and sensors and monitoring equipment. The central controller coordinates the operation of the vanadium redox flow storage unit and the refrigeration unit, controlling the charging, discharging, and cooling power according to electricity prices, load, and cooling demand.

[0032] This system coordinates the operation of the vanadium redox flow storage unit (VDR) and the refrigeration unit. At low temperatures, it controls the transfer of industrial waste heat to fuel cell stack 1 to ensure its normal operating temperature. It also controls the charging and discharging periods of the VDR based on electricity prices and load demand, for example, charging during off-peak hours at night and discharging during peak hours in the daytime. The power of the refrigeration unit is adjusted according to cooling load demand, such as by regulating the heat source flow rate of the absorption refrigeration unit to control cooling output. The system status is monitored in real time, and early warnings are issued for faults such as electrolyte leakage and system anomalies.

[0033] Sensors and monitoring equipment are used to monitor parameters such as power, cooling capacity, and temperature. They coordinate the operation of the vanadium redox flow storage unit (VDR) and the refrigeration unit, and monitor the parameters of each system. Power sensors are installed to monitor the voltage, current, and SOC (state of charge) of the VDR, allowing for real-time monitoring of its power status. Cooling capacity sensors are placed at the evaporator's refrigerant output end to measure the evaporation temperature, condensation pressure, and cooling capacity output of the refrigeration unit, enabling precise control of the cooling effect. Environmental sensors are used to monitor temperature and humidity, optimizing operating strategies, such as adjusting the operating parameters of the refrigeration system and the working mode of the thermal management system based on ambient temperature, and determining whether industrial waste heat needs to be introduced to heat the fuel cell stack.

[0034] Auxiliary equipment and safety systems include a liquid replenishment device, a filtration system, gas detectors, a fire extinguishing device, and a pressure relief valve. The liquid replenishment device replenishes the electrolyte and refrigerant to maintain a stable system liquid level. The filtration system purifies the electrolyte to prevent impurities from clogging the fuel cell stack 1 or refrigerant piping, thus affecting system performance. Gas detectors are installed in areas with leakage risks in the refrigerant system, such as to detect lithium bromide solution leaks. A fire extinguishing device is configured to address the potential overheating risk of the energy storage fuel cell stack 1. A pressure relief valve is installed to prevent excessive pressure in the electrolyte or refrigerant circuit. Gas detectors, fire extinguishing devices, and pressure relief valves ensure system safety and stable, safe operation.

[0035] Example 2

[0036] The present invention also provides a refrigeration method for a vanadium redox flow storage refrigeration system, comprising the following steps: The vanadium redox flow storage unit is controlled to charge and discharge. Its thermal management system collects the heat generated by the stack to the heat storage tank when the temperature is too high, or simultaneously activates the heat dissipation device. When the temperature is too low, industrial waste heat is introduced through the heat exchange network and the heating device heats the stack to ensure normal operation of the stack. Collect industrial waste heat, mix the heat collected by the vanadium redox flow storage unit with the industrial waste heat and raise the temperature, and use it as a heat source for the absorption refrigeration unit. The absorption refrigeration unit is activated to utilize the heat source for cooling, thereby meeting the cooling load requirements. The control system monitors system parameters in real time and adjusts operating status according to set strategies to ensure stable and safe system operation. It controls the charging of the vanadium redox flow storage unit during off-peak electricity hours and controls its discharge during peak electricity demand or when cooling load demand increases, providing power support for the refrigeration system. Based on seasonal and ambient temperature changes, it dynamically adjusts the operating mode of the vanadium redox flow storage unit's thermal management system, optimizing the switching timing between heat collection, heat dissipation, and industrial waste heat heating to improve energy utilization efficiency.

[0037] For example, in a summer control room air conditioning scenario (cooling load 500kW): During off-peak electricity hours at night (electricity price 0.3 yuan / kWh), the vanadium redox flow battery begins charging, generating heat. The thermal management system monitors the battery temperature and, when it is within a suitable range, transfers the heat to the storage tank via a heat exchanger network. During the day, as production begins and the electricity load increases, the battery discharges to meet the power needs of some equipment. Simultaneously, the heat dissipation generated by the vanadium redox flow battery in the storage tank (temperature approximately 50°C) mixes with the waste heat from the blast furnace cooling water (temperature approximately 65°C) through the heat exchanger network. The heat is then raised through the energy grade enhancement function of the organic Rankine cycle preheater, reaching a temperature of approximately 70°C, which is then fed into the generator of the absorption refrigeration unit. The absorption refrigeration unit produces 7°C chilled water, which is piped to the control room air conditioning system to cool the control room. If the battery temperature becomes too high during this process, the thermal management system activates the cooling fans / cooling tower for heat dissipation. This air conditioning system operates throughout the day without the need for externally purchased electricity, effectively reducing electricity costs.

[0038] Winter electrical equipment cooling scenario (300kW cooling load, requiring 24-hour constant temperature): When the ambient temperature is low, the thermal management system detects that the fuel cell stack temperature is too low during startup of the vanadium redox flow storage system. It introduces some waste heat from the steel plant (such as blast furnace flue gas waste heat, cooled to 50-60℃) through the heat exchanger network to heat the fuel cell stack. Heating stops once the temperature reaches a suitable range, and normal charging and discharging begins. The heat generated during operation is collected by the thermal management system and stored in the heat storage tank. In extreme low temperatures, the vanadium redox flow storage system continues to operate. The collected heat mixes with the waste heat from the steel plant and is then heated to 70℃ by an industrial waste heat recovery device, continuously supplying the absorption refrigeration unit as a heat source. If there is a temporary shortage of waste heat from the steel plant due to blast furnace maintenance, the energy storage battery discharges to drive an auxiliary heat pump, raising the heat source temperature from 50℃ to 70℃ to ensure the normal operation of the absorption refrigeration unit. This ensures uninterrupted cooling of the electrical equipment, maintaining a constant temperature environment of 20-25℃ and guaranteeing stable equipment operation.

[0039] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A full vanadium redox flow storage and refrigeration system, characterized in that, include: The vanadium redox flow storage unit is used to store and release electrical energy. Its thermal management system can collect the heat generated by the stack (1) and is equipped with heat dissipation and heating devices to ensure that the stack operates at a suitable temperature. The refrigeration unit is an absorption refrigeration unit used to use the heat collected by the thermal management system of the vanadium redox flow storage unit and industrial waste heat as heat sources for refrigeration. The energy coupling and integration device includes an electric coupling component and a thermal coupling component, which respectively realize the electric and thermal interaction between the vanadium redox flow energy storage unit and the refrigeration unit, and the thermal coupling component can introduce industrial waste heat into the thermal management system for heating the fuel cell stack (1). The control system and monitoring unit are used to coordinate the operation of the vanadium redox flow storage unit and the refrigeration unit, and to monitor the parameters of each system. Auxiliary equipment and safety systems are used to ensure the stable and safe operation of the system.

2. The all-vanadium redox flow storage and refrigeration system according to claim 1, characterized in that, The vanadium redox flow storage unit includes a fuel cell stack system, an electrolyte circulation system, and a thermal management system. The fuel cell system employs porous material electrode components, ion exchange membranes, and flow field plates to achieve the conversion of electrical energy into chemical energy. The electrolyte circulation system maintains electrolyte circulation through positive and negative electrolyte storage tanks, circulation pumps, and pipeline valves; The thermal management system uses an electric stack heat exchanger, temperature sensors, heat collection and dissipation devices, and a heating path connected to industrial waste heat to control the electrolyte temperature.

3. The all-vanadium redox flow storage and refrigeration system according to claim 2, characterized in that, When the thermal management system is operating normally and needs to collect heat, it transfers heat to the heat storage tank through a network of heat exchangers. When there is excess heat or the fuel cell stack temperature is too high, it activates the cooling fan / cooling tower to dissipate heat. When starting at low temperatures or when the ambient temperature is too low, it introduces industrial waste heat through the heat exchanger network to heat the fuel cell stack.

4. The all-vanadium redox flow storage and refrigeration system according to claim 1, characterized in that, The refrigeration unit uses lithium bromide-water as the working fluid pair and consists of a generator, a condenser, a throttling device, an evaporator, and an absorber. The generator receives a mixed heat source and drives the refrigeration cycle. The mixed heat source is formed by mixing the heat collected by the vanadium redox flow storage unit with industrial waste heat and then heating it up. The temperature range is 60-80℃.

5. The all-vanadium redox flow storage and refrigeration system according to claim 1, characterized in that, The power coupling component in the energy coupling and integration device achieves power interaction with the controller through a converter and a distribution box, and the converter has a bidirectional power conversion function. The thermal coupling component uses a heat exchanger network and a heat storage tank to mix the heat collected by the energy storage stack with industrial waste heat, and raises the temperature through industrial waste heat recovery. The industrial waste heat recovery device adopts an organic Rankine cycle preheater.

6. The all-vanadium redox flow storage and refrigeration system according to claim 1, characterized in that, The control system and monitoring unit includes a central controller and sensors and monitoring equipment. The central controller coordinates the operation of the energy storage and cooling system, controls the charging and discharging and cooling power according to the electricity price, load and cooling demand, and controls the transfer of industrial waste heat to the fuel cell stack at low temperatures. The sensors and monitoring equipment monitor parameters such as power, cooling capacity and temperature.

7. The all-vanadium redox flow storage and refrigeration system according to claim 1, characterized in that, The auxiliary equipment and safety system include a liquid replenishment device, a filtration system, a gas detector, a fire extinguishing device, and a pressure relief valve; the liquid replenishment device is used to replenish electrolyte and refrigerant, the filtration system is used to purify the electrolyte, and the gas detector, fire extinguishing device, and pressure relief valve are used to ensure system safety.

8. A refrigeration method based on the all-vanadium redox flow storage refrigeration system according to any one of claims 1-7, characterized in that, The following steps are involved: The vanadium redox flow storage unit is controlled to charge and discharge. Its thermal management system collects the heat generated by the stack to the heat storage tank according to the stack temperature, or starts heat dissipation when the temperature is too high. When starting at low temperature or when the ambient temperature is too low, industrial waste heat is introduced to heat the stack to ensure normal operation of the stack. Industrial waste heat is collected, and the heat collected by the vanadium redox flow storage unit is mixed with industrial waste heat and the temperature is increased to serve as the heat source for the absorption refrigeration unit. The absorption refrigeration unit is activated to utilize the heat source for cooling, thereby meeting the cooling load requirements. The control system monitors the parameters of each system in real time and adjusts the operating status according to the set strategy to ensure the stable and safe operation of the system.

9. The refrigeration method according to claim 8, characterized in that, The vanadium redox flow storage unit is charged during off-peak hours and discharged during peak hours or when cooling load demand increases, providing power support for the refrigeration system.

10. The refrigeration method according to claim 8, characterized in that, Based on seasonal and ambient temperature changes, the operating mode of the thermal management system of the vanadium redox flow storage unit is dynamically adjusted to optimize the switching timing of heat collection, heat dissipation and industrial waste heat heating, thereby improving energy utilization efficiency.

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