An electrochemical and osmotic energy synergistic high-efficiency power generation system driven by low-grade heat energy

Abstract

The present application relates to low-grade heat recovery and conversion technical field, specifically to a kind of low-grade heat driven electrochemical and permeation energy synergistic efficient power generation system, solve the existing low-grade heat for power generation, cannot realize the conversion and synergistic effect of electrochemical and permeation energy, and further lead to the inefficient use of low-grade heat Problem, including electrochemical cell unit, permeation energy capture unit, electrolyte heat regeneration unit and system control unit: the electrochemical cell unit is the core carrier of energy conversion and provides electrochemical work site and osmotic pressure generation environment using the non-equilibrium concentration gradient constructed by heat regeneration.The present application uses low-grade heat as the core driving source of system circulation, while maintaining the closed-loop operation of electrolyte using heat regeneration, creatively establishes a composite conversion mechanism that can simultaneously capture electrochemical discharge energy and permeation energy, significantly improves the energy comprehensive utilization efficiency and applicability of the system.

Description

Technical Field

[0001] This invention relates to the field of low-grade heat energy recovery and conversion technology, specifically to a high-efficiency power generation system driven by low-grade heat energy and synergistic electrochemical and osmotic energy. Background Technology

[0002] As the global energy structure shifts towards cleaner and more efficient energy sources, the efficient recovery and utilization of low-grade heat energy, such as industrial waste heat, geothermal energy, solar thermal energy, and data center waste heat, has become a key issue in the field of energy science. Due to the characteristics of these heat sources, such as small temperature differences, wide distribution, and relatively low energy density, developing new thermoelectric conversion technologies that can effectively adapt to their thermodynamic characteristics and are different from traditional heat engines has important scientific significance and application value for enriching the means of resource utilization of low-grade heat energy and improving the level of energy utilization.

[0003] In the exploration of novel thermoelectric conversion pathways, utilizing thermal energy to drive the regeneration of the electrochemical liquid working fluid to construct a concentration gradient within the system has proven to be a feasible energy conversion path. From a thermodynamic perspective, the non-equilibrium electrolyte concentration difference constructed by thermal energy is essentially a high chemical potential energy state. During the evolution from this non-equilibrium state to an equilibrium state, the system objectively contains two types of work potential that can be utilized: one is the electrochemical potential energy based on the redox reaction of active ions at the electrode interface, and the other is the transmembrane permeation potential energy based on the directional migration of solvent molecules at the membrane interface.

[0004] Existing methods for generating electricity using low-grade thermal energy cannot achieve the conversion and synergistic effect of electrochemical and osmotic energy, resulting in inefficient utilization of low-grade thermal energy. Therefore, this does not meet current requirements. To address this, we propose a high-efficiency power generation system driven by low-grade thermal energy that combines electrochemical and osmotic energy. Summary of the Invention

[0005] The purpose of this invention is to provide a high-efficiency power generation system driven by low-grade thermal energy, which combines electrochemical and osmotic energy to solve the problem mentioned in the background art that existing power generation systems using low-grade thermal energy cannot achieve the conversion and synergistic effect of electrochemical and osmotic energy, thus leading to inefficient utilization of low-grade thermal energy.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy, comprising an electrochemical battery unit, an osmotic energy capture unit, an electrolyte thermal regeneration unit, and a system control unit: The electrochemical battery unit is the core carrier of energy conversion and uses the non-equilibrium concentration gradient constructed by thermal regeneration to provide a place for electrochemical work and an environment for generating osmotic pressure. The electrochemical battery unit consists of a positive electrode reaction chamber and a negative electrode reaction chamber. The positive electrode reaction chamber and the negative electrode reaction chamber are respectively filled with electrolytes of different initial concentrations and used as circulating working fluids. The permeation energy capture unit uses the osmotic pressure generated by the thermally induced concentration gradient to drive solvent molecules to migrate across the membrane from the low concentration side to the negative electrode reaction chamber, resulting in a drop in the liquid level on the low concentration side and a rise in the liquid level in the negative electrode reaction chamber, thus forming a stable liquid level difference. The permeation energy capture unit includes a liquid flow channel and a mechanical power generation device. The electrolyte thermal regeneration unit utilizes low-grade heat energy to reverse the concentration dissipation caused by spontaneous permeation and restore the system to its initial high potential energy state, thereby completing a working cycle starting with heat energy. The electrolyte thermal regeneration unit consists of an evaporation separation module and a condensation recovery module.

[0007] Preferably, both the positive electrode reaction chamber and the negative electrode reaction chamber are made of one of transparent and translucent materials, and the inner walls of both the positive electrode reaction chamber and the negative electrode reaction chamber are equipped with liquid level sensors, which are used to monitor the liquid level of the electrolyte in real time.

[0008] Preferably, the positive electrode reaction chamber and the negative electrode reaction chamber are separated by an ion exchange membrane. The ion exchange membrane is a selective ion exchange membrane with high water molecule permeability and prevents cross-contamination of redox pairs in the positive and negative electrode reaction chambers. The redox pairs include, but are not limited to, zinc, iron and copper salts and their complexes.

[0009] Preferably, the liquid flow channel is connected to the negative electrode reaction chamber, and a flow control valve is provided at one end of the liquid flow channel near the negative electrode reaction chamber. The flow control valve is used to guide the liquid in the negative electrode reaction chamber to flow to the mechanical power generation device under the action of gravity during the electrochemical discharge stage.

[0010] Preferably, the mechanical power generation device is one of a micro turbine generator, a hydro generator, and an energy harvester based on the piezoelectric effect. The mechanical power generation device is used to convert the gravitational potential energy of the electrolyte into electrical energy to realize the cascade energy recovery after the electrochemical conversion unit discharges.

[0011] Preferably, the electrolyte thermal regeneration unit uses externally input low-grade thermal energy as the driving energy source, the evaporation separation module is used to heat the spent electrolyte after working by driving the low-grade heat source, and to evaporate part of the solvent water and return the concentrate to the negative electrode reaction chamber, and the condensation recovery module is used to condense the water vapor generated by evaporation into liquid water and return it to the positive electrode reaction chamber.

[0012] Preferably, the low-grade heat source includes, but is not limited to, solar energy, geothermal energy, and industrial waste heat; the evaporation separation module is one of a multi-effect evaporator, a membrane distillation assembly, and a vacuum evaporator; the condensation recovery module inputs water vapor through a pipeline; the condensation recovery module delivers the concentrate to the negative electrode reaction chamber through a pipeline; the condensation recovery module is cooled by air; and the water outlet of the condensation recovery module is connected to the positive electrode reaction chamber through a pipeline.

[0013] Preferably, the system control unit is signal-connected to the electrical components in the electrochemical battery unit, the osmotic energy capture unit, and the electrolyte thermal regeneration unit. The system control unit is used to coordinate the cyclical operation of the electrochemical and osmotic energy synergistic high-efficiency power generation system according to a preset program. The execution sequence of the electrochemical and osmotic energy synergistic high-efficiency power generation system includes the following steps: S1: Charging and Osmotic Energy Construction Stage. After initialization and thermal regeneration of the electrochemical and osmotic energy synergistic high-efficiency power generation system, a high concentration gradient is maintained between the electrolytes in the positive and negative electrode reaction chambers of the electrochemical battery unit, which is actively constructed by low-grade thermal energy. The high concentration gradient refers to the ratio of high-concentration electrolyte to low-concentration electrolyte, and the ratio is at least 2:1. The system control unit closes the charging circuit of the electrochemical battery unit and keeps the liquid circuit valve of the osmotic energy harvesting unit closed. Then, an external power source is connected to drive the electrochemical battery unit to carry out electrochemical reactions, converting electrical energy into chemical energy for storage. At the same time, the huge osmotic pressure generated by the high concentration gradient is used as a driving force to force solvent molecules to spontaneously migrate from the low concentration side to the high concentration side, causing the liquid level in the positive electrode reaction chamber to drop and the liquid level in the negative electrode reaction chamber to rise until the osmotic equilibrium of the positive and negative electrode electrolytes is reached. S2: Electrochemical discharge stage. When the system reaches osmotic equilibrium, the system control unit first switches the electrochemical battery unit to the discharge circuit. At this time, although the electrolyte concentration changes due to osmosis, the system still maintains a significant concentration gradient. The electrochemical battery unit is connected to an external load and utilizes the highly active electrode after charging and the Nernst potential provided by the remaining concentration gradient to efficiently output high-grade electrochemical electrical energy. S3: In the mechanical power generation stage of permeation energy, after the electrochemical discharge is completed, the system opens the flow control valve of the permeation energy capture unit. Utilizing the high liquid level difference established by the permeation effect during the charging and permeation energy construction stages, the electrolyte is driven to flow to the mechanical power generation device, converting the stored gravitational potential energy into electrical energy output, realizing the cascade recovery of energy and capturing the permeation energy dissipated in the traditional system. S4: Electrolyte thermal regeneration and reset stage. After the mechanical power generation of the permeation energy is completed, the system control unit controls the pipeline valves to transport the spent electrolyte after the work is done to the electrolyte thermal regeneration unit. Then, the evaporation separation module is started, using the externally input low-grade thermal energy as the driving source to heat and evaporate the spent electrolyte. The separated solvent vapor is introduced into the condensation recovery module to condense into liquid solvent. Then, the system control unit pressurizes the regenerated concentrated electrolyte and sends it back to the negative electrode reaction chamber of the electrochemical battery unit through the solution pump. The condensed and recovered liquid solvent is pressurized and sent back to the positive electrode reaction chamber through the solution pump, so that the concentration gradient and liquid level of the working fluid in the system are restored to the initial high potential energy state. Finally, all control valves are reset, and the system is in a ready state. It can restart the next working cycle starting from the charging and permeation energy construction stage according to the preset instructions.

[0014] Compared with the prior art, the beneficial effects of the present invention are: This invention deeply couples a permeation energy capture mechanism into an electrochemical conversion system driven by low-grade thermal energy. Based on electrochemical discharge using thermally induced concentration gradients, it further utilizes the spontaneous permeation effect during electrolyte operation to drive mechanical power generation. The invention organically integrates the above-mentioned dual work process with a thermally driven closed-loop regeneration mechanism of the electrolyte, thereby achieving synergistic output of electrochemical energy and permeation mechanical energy and sustainable and efficient thermoelectric conversion of the system, significantly improving the utilization efficiency of low-grade thermal energy. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the initial state of the electrochemical and osmotic energy synergistic high-efficiency power generation system of the present invention; Figure 2 This is a schematic diagram illustrating the working principle of the charging and permeation energy construction stage of the present invention; Figure 3 This is a schematic diagram illustrating the principle of the electrochemical discharge stage of the present invention; Figure 4 This is a schematic diagram illustrating the principle of the mechanical power generation stage of the permeable energy method in this invention. Figure 5 This is a schematic diagram illustrating the principle of the electrolyte thermal regeneration and reset stage of the present invention; Figure 6 This is a schematic diagram of the working cycle operation of the present invention based on thermal regeneration electrochemical cycle; Figure 7 This is a schematic diagram of the working cycle operation of the present invention based on a conventional electrochemical system.

[0016] In the diagram: 11. Positive electrode reaction chamber; 12. Negative electrode reaction chamber; 13. Ion exchange membrane; 21. Liquid flow channel; 22. Mechanical power generation device; 23. Flow control valve; 31. Evaporation separation module; 32. Condensation recovery module; 33. Solution pump. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0018] Please see Figure 1 The present invention provides an embodiment of a low-grade thermal energy driven electrochemical and osmotic energy synergistic high-efficiency power generation system, comprising an electrochemical battery unit, an osmotic energy capture unit, an electrolyte thermal regeneration unit, and a system control unit. The electrochemical battery unit is the core carrier of energy conversion and utilizes the non-equilibrium concentration gradient constructed by thermal regeneration to provide an electrochemical work site and an environment for generating osmotic pressure. The electrochemical battery unit consists of a positive electrode reaction chamber 11 and a negative electrode reaction chamber 12. The positive electrode reaction chamber 11 and the negative electrode reaction chamber 12 are respectively filled with electrolytes of different initial concentrations and used as circulating working fluids. Both the positive electrode reaction chamber 11 and the negative electrode reaction chamber 12 are made of either transparent or semi-transparent materials. The inner walls of both the positive electrode reaction chamber 11 and the negative electrode reaction chamber 12 are equipped with liquid level sensors, which are used to monitor the liquid level of the electrolyte in real time. The positive electrode reaction chamber 11 and the negative electrode reaction chamber 12 are separated by an ion exchange membrane 13. The ion exchange membrane 13 is a selective ion exchange membrane 13. The ion exchange membrane 13 has high water molecule permeability and blocks cross-contamination of redox pairs in the positive electrode reaction chamber 11 and the negative electrode reaction chamber 12. The redox pairs include, but are not limited to, zinc, iron and copper salts and their complexes.

[0019] Furthermore, the permeation energy capture unit utilizes the osmotic pressure generated by the thermally induced concentration gradient to drive solvent molecules to migrate across the membrane from the low concentration side to the negative electrode reaction chamber 12, resulting in a drop in the liquid level on the low concentration side and a rise in the liquid level on the negative electrode reaction chamber 12, thus forming a stable liquid level difference. The permeation energy capture unit includes a liquid flow channel 21 and a mechanical power generation device 22. The liquid flow channel 21 is connected to the negative electrode reaction chamber 12, and a flow control valve 23 is provided at one end of the liquid flow channel 21 near the negative electrode reaction chamber 12. The flow control valve 23 is used to guide the liquid in the negative electrode reaction chamber 12 to flow to the mechanical power generation device 22 under the action of gravity during the electrochemical discharge stage. The mechanical power generation device 22 is one of three: a micro turbine generator, a water turbine generator, and an energy harvester based on the piezoelectric effect. The mechanical power generation device 22 is used to convert the gravitational potential energy of the electrolyte into electrical energy to realize the cascade energy recovery after the electrochemical conversion unit is discharged.

[0020] Among them, the electrolyte thermal regeneration unit uses low-grade heat energy to reverse the concentration dissipation caused by spontaneous permeation and restore the initial high potential energy state of the system, thereby completing the working cycle starting from heat energy. The electrolyte thermal regeneration unit consists of an evaporation separation module 31 and a condensation recovery module 32. The electrolyte thermal regeneration unit uses externally input low-grade heat energy as the driving energy. The evaporation separation module 31 is used to heat the spent electrolyte after working through the low-grade heat source, and to evaporate part of the solvent water and return the concentrate to the negative electrode reaction chamber 12. The condensation recovery module 32 is used to condense the water vapor generated by evaporation into liquid water and return it to the positive electrode reaction chamber 11. Low-grade heat sources include, but are not limited to, solar energy, geothermal energy, and industrial waste heat. The evaporation separation module 31 is one of the three: multi-effect evaporator, membrane distillation component, and vacuum evaporator. The condensation recovery module 32 inputs water vapor through pipelines and transports the concentrate to the negative electrode reaction chamber 12 through pipelines. The condensation recovery module 32 is cooled by air, and the water outlet of the condensation recovery module 32 is connected to the positive electrode reaction chamber 11 through pipelines.

[0021] Furthermore, the system control unit is connected to the electrical components in the electrochemical battery unit, the permeation energy capture unit, and the electrolyte thermal regeneration unit. The system control unit is used to coordinate the electrochemical and permeation energy synergistic high-efficiency power generation system to operate cyclically according to a preset program.

[0022] Please see Figures 2 to 7 The execution sequence of the electrochemical and osmotic energy synergistic high-efficiency power generation system includes the following steps: S1: Charging and Osmotic Energy Construction Stage. After initialization and thermal regeneration of the electrochemical and osmotic energy synergistic high-efficiency power generation system, a high concentration gradient is maintained between the electrolytes in the positive electrode reaction chamber 11 and the negative electrode reaction chamber 12 of the electrochemical battery unit, which is actively constructed by low-grade thermal energy. The high concentration gradient refers to the ratio of high-concentration electrolyte to low-concentration electrolyte, and the ratio is at least 2:1. The system control unit closes the charging circuit of the electrochemical battery unit and keeps the liquid circuit valve of the osmotic energy harvesting unit closed. Then, an external power source is connected to drive the electrochemical battery unit to carry out electrochemical reactions, converting electrical energy into chemical energy for storage. At the same time, the huge osmotic pressure generated by the high concentration gradient is used as a driving force to force solvent molecules to spontaneously migrate from the low concentration side to the high concentration side, causing the liquid level in the positive electrode reaction chamber 11 to drop and the liquid level in the negative electrode reaction chamber 12 to rise until the osmotic equilibrium of the positive electrode electrolyte and the negative electrode electrolyte is reached. S2: Electrochemical discharge stage. When the system reaches osmotic equilibrium, the system control unit first switches the electrochemical battery unit to the discharge circuit. At this time, although the electrolyte concentration changes due to osmosis, the system still maintains a significant concentration gradient. The electrochemical battery unit is connected to an external load and utilizes the highly active electrode after charging and the Nernst potential provided by the remaining concentration gradient to efficiently output high-grade electrochemical electrical energy. S3: In the mechanical power generation stage of permeation energy, after the electrochemical discharge is completed, the system opens the flow control valve 23 of the permeation energy capture unit. Utilizing the high liquid level difference established by the permeation effect during the charging and permeation energy construction stages, the electrolyte is driven to flow to the mechanical power generation device 22, converting the stored gravitational potential energy into electrical energy output, realizing the cascade recovery of energy and capturing the permeation energy dissipated in the traditional system. S4: Electrolyte thermal regeneration and reset stage. After the mechanical power generation of the permeation energy is completed, the system control unit controls the pipeline valves to transport the spent electrolyte after the work is done to the electrolyte thermal regeneration unit. Then, the evaporation separation module 31 is started, using the externally input low-grade thermal energy as the driving source to heat and evaporate the spent electrolyte. The separated solvent vapor is introduced into the condensation recovery module 32 to condense into liquid solvent. Then, the system control unit pressurizes the regenerated concentrated electrolyte through the solution pump 33 and sends it back to the negative electrode reaction chamber 12 of the electrochemical battery unit. The condensed and recovered liquid solvent is pressurized through the solution pump 33 and sent back to the positive electrode reaction chamber 11, so that the concentration gradient and liquid level of the working fluid in the system are restored to the initial high potential energy state. Finally, all control valves are reset, and the system is in a ready state. It can restart the next working cycle starting from the charging and permeation energy construction stage according to the preset instructions.

[0023] Please see Figure 6 Example 1: Dual-effect synergistic optimization example Within the framework of thermal regeneration electrochemical cycle, this is an efficient implementation method that deeply and synergistically utilizes the thermoelectric effect and the concentration electrochemical effect driven by the permeation process. Thermal regeneration electrochemical cycle is a type of technology that utilizes the temperature dependence of electrode potential and improves energy conversion efficiency through periodic temperature changes.

[0024] The positive electrode of the aqueous electrochemical cell unit uses a potassium ferrocyanide / potassium ferrocyanide couple ( Its standard electrode potential has a negative temperature coefficient, and experimental measurements show that... Approximately -1.4mV / K, the negative electrode uses a copper / copper nitrate couple ( It has a positive temperature coefficient. With a temperature coefficient of approximately +0.4 mV / K, the combination of the two electrode pairs enables the battery to achieve a large overall temperature coefficient, laying the foundation for efficient cycling driven by temperature changes. More importantly, in the coupling system of this invention, the osmosis phenomenon accompanying the charging and discharging process actively changes the concentration of the electrolyte in both chambers, thereby significantly changing the electrode potential according to the Nernst equation. This osmosis-driven "concentration electrochemical effect" combined with the aforementioned "thermoelectrochemical effect" constitutes the dual theoretical basis for achieving synergistic energy conversion and amplification in this embodiment.

[0025] The specific configuration is as follows: the positive electrode reaction chamber 11 is filled with 0.1M of... Solution (containing 1M) As the supporting electrolyte, the electrodes are made of carbon cloth; the negative electrode reaction chamber 12 is filled with 3.0M of... The solution and electrodes are made of copper foil. The electrolyte levels in the two chambers are level, forming an initial concentration gradient of up to 30 times. The ion exchange membrane 13 is an anion exchange membrane (e.g., Astom AXP-D type), with an ion exchange capacity of about 1.2 meq / g and a thickness of about 0.12 mm, which ensures ion selectivity while having a suitable water molecule permeation flux.

[0026] After system initialization or thermal regeneration is completed, the charging and permeation energy construction phase begins. First, an external heat source uniformly heats electrochemical cell unit 1 to 60°C. At this high temperature, the battery's open-circuit voltage decreases compared to the 25°C reference voltage, and the decrease is... It can be estimated by the following formula: Subsequently, electrochemical cell unit 1 was charged at a constant current of 2 mA at 60°C. The charging process simultaneously triggered two closely coupled physicochemical processes: one was an electrochemical reaction and ion migration driven by an applied electric field; the other was the significant spontaneous permeation of water molecules from the positive electrode chamber (low concentration side) to the negative electrode chamber (high concentration side) through the ion exchange membrane, driven by an initial concentration gradient of up to 30 times. To fully demonstrate the synergistic effect of this invention, under the system parameters set in this embodiment (such as membrane characteristics, initial concentration difference, charging current, and duration), and based on the principles of osmotic equilibrium and mass conservation, the estimated volume that can be achieved during charging is... The net migration of water occurs. This migration process leads to a corresponding decrease in the volume of the positive electrode chamber, and a significant increase in the electrolyte concentration from the initial 0.1 mol / L to approximately 0.4 mol / L; simultaneously, the volume of the negative electrode chamber increases due to the reception of the migrated water, and the electrolyte concentration is correspondingly diluted from 3.0 mol / L to approximately 1.7 mol / L. This significant concentration change is determined according to the Nernst equation. It will directly and strongly change the electrode potential. This is relevant to the positive electrode charging reaction. Its potential change is (Positive electrode potential decreases). Regarding the negative electrode charging reaction... Its potential change is (Positive electrode potential rises). Therefore, the decrease in charging voltage of aqueous electrochemical cell unit 1 caused solely by the osmotic concentration gradient effect is: Thermoelectric effect ( ) and significantly enhanced osmotic concentration gradient effect ( This achieves a powerful synergistic increase, resulting in a maximum reduction in total charging voltage compared to the baseline condition with no penetration at 25°C. At a reference charging voltage of 240m, this optimized synergistic effect reduces charging energy consumption by nearly 46.7%, fully demonstrating the design advantages of enhancing system performance by regulating the amount of infiltrated water. The directional migration of water synchronously causes the liquid level in the positive electrode chamber to drop and the liquid level in the negative electrode chamber to rise, creating a significant liquid level difference. The increase in the amount of migrating water causes a difference in liquid level. The maximum depth can reach 1.2m (under experimental conditions). This liquid level difference stores gravitational potential energy. (Pick After charging is complete, the system undergoes a cooling process to restore it to 25°C. The battery open-circuit voltage subsequently rises.

[0027] The system then executes an electrochemical discharge process. The system control unit switches the cooled electrochemical cell to the discharge circuit, outputting high-grade electrical energy at a constant current of 2mA. During this process, the system deliberately keeps the flow control valve 23 of the permeation energy capture unit closed. The purpose of this strategy is to temporarily "lock" the high liquid level difference (gravitational potential energy) and the remaining concentration gradient (chemical potential energy) established in stage S1 within the reaction chamber. Thanks to the closed liquid path, the electrochemical discharge is maintained under high hydrostatic pressure and concentration potential energy conditions throughout, avoiding the decay of Nernst potential caused by premature loss of the working fluid, thereby ensuring the electrochemical discharge voltage. At its optimal level. The electrical energy output from electrochemical work can be expressed by the formula... Calculated.

[0028] After the electrochemical discharge ends, the system immediately opens the flow control valve 23 on the liquid flow channel, entering the permeation energy mechanical power generation stage. At this time, the working fluid stored in the high concentration side reaction chamber establishes a high liquid level difference in stage S1. The mechanical power generation device 22 is driven to operate. The total mechanical energy recovered during the liquid level difference power generation process can be expressed by the formula... The estimation is based on the overall efficiency of the micro turbine generator. =0.65, and the liquid level difference drops from 1.2m to 0m during the discharge process. Calculations show that the mechanical energy contributed by the permeation energy harvesting unit is equivalent to increasing the energy conversion efficiency by approximately 25% per cycle on the basis of an equivalent electrochemical system. This pure incremental energy comes entirely from the efficient recovery of the permeation energy discarded in the traditional system, and is achieved through the coordinated operation of the mechanical power generation device 22 and the flow control valve V1, which is the key efficiency-enhancing path of this invention.

[0029] After the discharge ends, the system immediately enters the electrolyte thermal regeneration and reset stage. This stage, driven by low-grade heat energy through an evaporation-condensation process, achieves precise reset and circulation of the working medium, which is the core guarantee for the sustainable operation of this system. Specifically, the system transports all the high-concentration electrolyte flowing out of the micro-turbine generator after the liquid level difference power generation has been completed to the evaporation separation module 31. Driven by a low-grade heat source above 100°C, water molecules in the solution evaporate and are efficiently separated from the solute; the resulting condensation recovery module 32 completely condenses and recovers it into high-purity water. The evaporated and concentrated solution is returned to the high-concentration negative electrode chamber through the solution pump 33, while the recovered pure water enters the low-concentration positive electrode chamber. This process not only precisely restores the electrolyte concentration in both chambers to the initial concentration gradient (3.0M for negative electrode electrolyte and 0.1M for positive electrode electrolyte), but also resets the liquid levels on both sides to the initial level state.

[0030] To quantify the performance of the system of this invention as a high-efficiency thermoelectric conversion device, the total conversion efficiency of the system is defined as the net electrical energy output per cycle (…). ) and input thermal energy ( The ratio of ) is calculated using the following formula: .in: It outputs energy for electrochemical discharge; Energy is consumed to charge electrochemical processes; The mechanical power generation energy is generated by the infiltration energy harvesting unit; The total thermal energy consumed by the thermal regeneration unit (including the sensible heat of heating the spent electrolyte to the evaporation temperature) and the latent heat required for solvent evaporation ).

[0031] Under the operating conditions of this embodiment, comprehensive calculations show that, with the same thermal energy input ( Under these conditions, the overall thermoelectric conversion efficiency of this embodiment is... Compared to traditional thermal regenerative battery systems without integrated permeation capture mechanisms, this represents an improvement of approximately 35%-50% (depending on the specific temperature difference and working fluid concentration). This data strongly supports the technological advantages of this system as a novel, highly efficient thermoelectric conversion device.

[0032] Please see Figure 7 Example 2: Core principle example, applicable to conventional electrochemical batteries This embodiment aims to illustrate the most basic and universal application of the invention, demonstrating the system's effectiveness in electrochemical systems with conventional electrode potential characteristics without an active thermal management unit. It establishes a highly efficient energy recovery paradigm driven solely by thermally induced concentration gradients. Through unique system coupling, it pioneeringly captures and converts the solvent transmembrane permeation energy, which is inherently present in electrolyte circulation but is usually considered a dissipative term, into effective electrical energy output. The non-TREC conventional path operates at a constant temperature (e.g., room temperature).

[0033] In this embodiment, the electrochemical battery unit uses an aqueous zinc-iodine battery system. Specifically, the positive electrode reaction chamber 11 is charged with 1M... The aqueous solution and the electrode are iodine electrodes supported on porous carbon materials (the active material is...). (Electrical pair); the negative electrode reaction chamber 12 is filled with 10M (potentially charged with a specific chemical process). An aqueous solution is used, with zinc foil as the electrode (the active material being the Zn²⁺ / Zn redox couple), forming a 10-fold initial concentration gradient. Ion exchange membrane 13 is an anion exchange membrane (as described above), which effectively blocks polyiodide ions. It has cross-linking and a suitable water molecule permeation flux to ensure battery cycle stability and permeation efficiency.

[0034] The system directly enters the charging and osmotic energy construction stage at room temperature. During constant current charging, water molecules permeate from the positive electrode chamber to the negative electrode chamber driven by the concentration gradient. Based on the principles of osmotic equilibrium and mass conservation, the volume that can be achieved during charging is estimated to be [volume value missing]. The net migration of 0.3L of water creates a level difference of approximately 0.75m. This process leads to an increase in the electrolyte concentration in the positive electrode chamber and a decrease in the electrolyte concentration in the negative electrode chamber.

[0035] Subsequently, the system enters a dual-channel cascaded power generation mode. The first step is the electrochemical discharge process. The system control unit switches the zinc-iodine electrochemical battery unit to the discharge circuit, utilizing the high electrode activity and remaining concentration gradient after charging to output electrical energy. During this period, the flow control valve 23 is deliberately kept closed to maintain the hydrostatic pressure and electrolyte concentration in the reaction chamber, ensuring the electrochemical work process proceeds under optimal thermodynamic conditions. After the electrochemical work is completed, the osmotic energy mechanical power generation process is executed. The system opens the flow control valve 23, utilizing the high liquid level difference established by the osmotic effect in stage S1. (Approximately 0.75m) Drives the mechanical power generation device 22. This process releases the stored fluid potential energy and converts it into electrical energy until the liquid level returns to equilibrium.

[0036] Finally, the system enters the electrolyte thermal regeneration and reset stage. An external low-grade heat source drives the evaporation separation module to separate and concentrate the spent electrolyte. The concentrate and condensate are precisely pumped back to the negative and positive electrode chambers, respectively, completely resetting the concentration gradient and liquid level of the working fluid. This step, as an energy injection source, converts thermal energy back into the high chemical potential energy of the working fluid, providing the necessary thermodynamic basis for driving the S1 stage of the next cycle, thus achieving closed-loop continuous operation of the system.

[0037] Under the operating conditions of this embodiment, comprehensive calculations show that, with the same thermal energy input ( Under these conditions, the overall thermoelectric conversion efficiency of this embodiment is... Compared to traditional thermal regenerative battery systems without integrated permeation capture mechanisms, this represents an improvement of approximately 18%-30% (depending on the specific temperature difference and working fluid concentration). This embodiment demonstrates that even without introducing complex thermal management, the present invention still exhibits highly efficient utilization of low-grade thermal energy.

[0038] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the 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 the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy generation, characterized in that, It includes an electrochemical cell unit, a permeation energy capture unit, an electrolyte thermal regeneration unit, and a system control unit: The electrochemical battery unit is the core carrier of energy conversion and provides an electrochemical work site and osmotic pressure generation environment by utilizing the non-equilibrium concentration gradient constructed by thermal regeneration. The electrochemical battery unit consists of a positive electrode reaction chamber (11) and a negative electrode reaction chamber (12). The positive electrode reaction chamber (11) and the negative electrode reaction chamber (12) are respectively filled with electrolytes of different initial concentrations and used as circulating working fluids. The permeation energy capture unit uses the osmotic pressure generated by the thermally induced concentration gradient to drive solvent molecules to migrate across the membrane from the low concentration side to the negative electrode reaction chamber (12), resulting in a drop in the liquid level on the low concentration side and a rise in the liquid level on the negative electrode reaction chamber (12), forming a stable liquid level difference. The permeation energy capture unit includes a liquid flow channel (21) and a mechanical power generation device (22). The electrolyte thermal regeneration unit uses low-grade heat energy to reverse the concentration dissipation caused by spontaneous permeation and restore the initial high potential energy state of the system, thereby completing the working cycle starting from heat energy. The electrolyte thermal regeneration unit consists of an evaporation separation module (31) and a condensation recovery module (32).

2. The high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy according to claim 1, characterized in that: The positive electrode reaction chamber (11) and the negative electrode reaction chamber (12) are both made of one of the transparent and semi-transparent materials. The inner walls of the positive electrode reaction chamber (11) and the negative electrode reaction chamber (12) are equipped with liquid level sensors, which are used to monitor the liquid level of the electrolyte in real time.

3. The high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy according to claim 2, characterized in that: The positive electrode reaction chamber (11) and the negative electrode reaction chamber (12) are separated by an ion exchange membrane (13). The ion exchange membrane (13) is a selective ion exchange membrane (13). The ion exchange membrane (13) has high water molecule permeability and blocks cross-contamination of redox pairs in the positive electrode reaction chamber (11) and the negative electrode reaction chamber (12). The redox pairs include, but are not limited to, zinc, iron and copper salts and their complexes.

4. The high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy according to claim 3, characterized in that: The liquid flow channel (21) is connected to the negative electrode reaction chamber (12). A flow control valve (23) is provided at one end of the liquid flow channel (21) near the negative electrode reaction chamber (12). The flow control valve (23) is used to guide the liquid in the negative electrode reaction chamber (12) to flow to the mechanical power generation device (22) under the action of gravity during the electrochemical discharge stage.

5. The high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy according to claim 4, characterized in that: The mechanical power generation device (22) is one of three: a micro turbine generator, a water turbine generator, and an energy harvester based on the piezoelectric effect. The mechanical power generation device (22) is used to convert the gravitational potential energy of the electrolyte into electrical energy to realize the cascade energy recovery after the electrochemical conversion unit is discharged.

6. The high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy according to claim 5, characterized in that: The electrolyte thermal regeneration unit uses externally input low-grade thermal energy as the driving energy source. The evaporation separation module (31) is used to heat the spent electrolyte after work by driving the low-grade heat source, and to evaporate part of the solvent water and return the concentrate to the negative electrode reaction chamber (12). The condensation recovery module (32) is used to condense the water vapor generated by evaporation into liquid water and return it to the positive electrode reaction chamber (11).

7. The high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy according to claim 6, characterized in that: The low-grade heat source includes, but is not limited to, solar energy, geothermal energy and industrial waste heat. The evaporation separation module (31) is one of the three: multi-effect evaporator, membrane distillation component and vacuum evaporator. The condensation recovery module (32) inputs water vapor through a pipeline. The condensation recovery module (32) transports the concentrate to the negative electrode reaction chamber (12) through a pipeline. The condensation recovery module (32) is cooled by air. The water outlet of the condensation recovery module (32) is connected to the positive electrode reaction chamber (11) through a pipeline.

8. The high-efficiency power generation system driven by low-grade thermal energy and synergistic electrochemical and osmotic energy according to claim 7, characterized in that: The system control unit is connected to the electrical components in the electrochemical battery unit, the osmotic energy capture unit, and the electrolyte thermal regeneration unit. The system control unit is used to coordinate the cyclical operation of the electrochemical and osmotic energy synergistic high-efficiency power generation system according to a preset program. The execution sequence of the electrochemical and osmotic energy synergistic high-efficiency power generation system includes the following steps: S1: Charging and osmotic energy construction stage. After the initialization and thermal regeneration of the electrochemical and osmotic energy synergistic high-efficiency power generation system, a high concentration gradient is maintained between the electrolyte in the positive electrode reaction chamber (11) and negative electrode reaction chamber (12) of the electrochemical battery unit, which is actively constructed by low-grade thermal energy. The high concentration gradient refers to the ratio of high-concentration electrolyte to low-concentration electrolyte, and the ratio is at least 2:

1. The system control unit closes the charging circuit of the electrochemical battery unit and keeps the liquid circuit valve of the osmotic energy harvesting unit closed. Then, an external power source is connected to drive the electrochemical battery unit to carry out electrochemical reaction, converting electrical energy into chemical energy for storage. At the same time, the huge osmotic pressure generated by the high concentration gradient is used as the driving force to force the solvent molecules to spontaneously migrate from the low concentration side to the high concentration side, resulting in the liquid level of the positive electrode reaction chamber (11) decreasing and the liquid level of the negative electrode reaction chamber (12) increasing until the osmotic balance of the positive electrode electrolyte and the negative electrode electrolyte is reached. S2: Electrochemical discharge stage. When the system reaches osmotic equilibrium, the system control unit first switches the electrochemical battery unit to the discharge circuit. At this time, although the electrolyte concentration changes due to osmosis, the system still maintains a significant concentration gradient. The electrochemical battery unit is connected to an external load and utilizes the highly active electrode after charging and the Nernst potential provided by the remaining concentration gradient to efficiently output high-grade electrochemical electrical energy. S3: In the mechanical power generation stage of permeation energy, after the electrochemical discharge is completed, the system opens the flow control valve (23) of the permeation energy capture unit. Utilizing the high liquid level difference established by the permeation effect during the charging and permeation energy construction stages, the electrolyte is driven to flow to the mechanical power generation device (22), converting the stored gravitational potential energy into electrical energy output, realizing the cascade recovery of energy, and capturing the permeation energy dissipated in the traditional system. S4: Electrolyte thermal regeneration and reset stage. After the mechanical power generation of the permeation energy is completed, the system control unit controls the pipeline valves to transport the spent electrolyte after the work is done to the electrolyte thermal regeneration unit. Then, the evaporation separation module (31) is started. Using the low-grade heat energy input from the outside as the driving source, the spent electrolyte is heated and evaporated and separated. The separated solvent vapor is introduced into the condensation recovery module (32) and condensed into liquid solvent. Then, the system control unit pressurizes the regenerated concentrated electrolyte through the solution pump (33) and transports it back to the negative electrode reaction chamber (12) of the electrochemical battery unit. The condensed and recovered liquid solvent is pressurized through the solution pump (33) and transported back to the positive electrode reaction chamber (11). This restores the concentration gradient and liquid level of the working fluid in the system to the initial high potential energy state. Finally, all control valves are reset and the system is in a ready state. The next working cycle starting from the charging and permeation energy construction stage can be restarted according to the preset instructions.

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