JPH06215791A - Thermoelectrochemical apparatus and method - Google Patents

Abstract

PURPOSE: To simply, safely enhance efficiency of a device by forming a battery with an ion permeable barrier in common, an anode section and a cathode section each has the required solution, and treating the reaction product from each section with a heat exchanger, a flushing stripper, and a condenser. CONSTITUTION: An electrochemical battery 10 is formed with an ion permeable barrier 20 in common, an anode section 16, and a cathode section 18 having an anode 22 and a cathode 24 respectively. An anode solution which consists of a concentrated solution of strong Brϕn sted acid, consumes hydrogen ions during generation of current, and generates hydrogen gas and a first cell reaction product is supplied to the anode section, and a cathode solution which is a molten salt solution, reduces hydrogen gas concentration in the anode section 16, and produces a second cell reaction product is supplied to the cathode section 18. These reaction products are treated with a heat exchanger 30, a flushing stripper 12, and a condenser 14, and supplied to the battery 10. By the simple constitution and use of environmentally safety electrolyte, the efficiency of a device is simply, safely enhanced.

Description

FIELD OF THE INVENTION The present invention relates generally to heat regenerative electrochemical devices and methods. Specifically, the present invention relates to improved thermoelectrochemical devices and methods that use phosphoric acid and ammonium phosphate as the working fluids of acid concentrating batteries.

(Prior Art) Thermoelectrochemical devices or regenerated electrochemical devices have been extensively studied since the 1950s. In these devices, the working substances produced in electrochemical cells (fuel cells, cells, galvanic cells, EMF cells, etc.) are regenerated by the introduction of thermal energy. In many respects, these devices are similar to secondary batteries, except that the electrochemically active electrode reactants are often produced thermally rather than electrically.

 Typical of thermally regenerated electrochemical devices are: 1) Krumpelt et al., U.S. Pat. No. 4,292,378, Sept. 29, 1981; 2) Loutfy et al., U.S., Oct. 18, 1983. No. 4,410,606 and U.S. Pat. No. 3,536,530 issued by Anthes et al. On October 27, 1970. The Athens et al. Device includes a tellurium chloride electrochemical cell and a regenerator that thermally regenerates the electrode reactants at temperatures of about 550 ° C. using complexing agents such as gallium chloride and aluminum chloride. ing.

Krumpelt et al. Describe a thermoelectrochemical concentrator battery using an aluminum metal electrode and an electrolyte consisting of ethylpyridinium chloride solvent and aluminum chloride. An electric current is generated between the electrodes by maintaining the concentration gradient such that the concentration of aluminum ions at the anode is low and the concentration of aluminum ions at the cathode is high. The concentration gradient in the system of Krumpelt et al. Is that the electrolytic solution is constantly circulated in the distiller to distill low-boiling aluminum chloride and distillate with high aluminum ion concentration and lower fraction with low aluminum ion concentration. Is maintained by gaining. The distillate rich in aluminum ions is sent to the cathode to replenish the scattered aluminum ions at the cathode, and the lower fraction depleted in aluminum ions is diluted to dilute the aluminum ions generated during the generation of the electric current, and is the anode. Returned to. Krumprlt et al. Further mention the use of iron, antimony and silicon electrodes in combination with various alkali metals, indium, salts of ammonia and ionic solvents such as POH ₃ and SOH ₃ (H is a halide). ing.

 Loutfy et al. Have published a thermoelectrochemical system based on the special properties of copper in aqueous solution. In uncomplexed media such as sulfuric acid, the redox potentials of the CU (II) / CU (I) and CU (I) / CU (0) couples are higher in the cuprous ion than in the cupric ion. Show the order of anxiety. In some complexing media such as acetonitril in sulfuric acid, the potential of the copper electrode is reversed because the cupric complex is more stable than the cuprous ion. Loutfy et al. Proposed an electrochemical cell that takes advantage of this property of copper in an aqueous solution to generate an electric potential using electrolytes with various concentrations of complexing agents. In order to maintain the concentration of complexing agent in the desired range, the electrolyte is constantly removed from the cell and at least thermally treated to remove the complexing agent from the solvent.

(Problems to be Solved by the Invention) Although the above device is suitable for their purposes, it maximizes the efficiency of thermal regeneration of the reactants and the generation of products at high power densities and their own efficiency. In addition, additional thermoelectrochemical equipment must still be provided to maximize overall system efficiency. Many of the known devices include complex pumping equipment, plumbing, and decoupling equipment, which increases equipment cost and efficiency. In addition, currently used electrolytes contain complexing agents and complex reactants that require tight control of reactant concentrations. Therefore, it is necessary to have a thermoelectrochemical device that has a constantly simplified electrolyte composition and a simplified thermal regenerator, and that has appropriate device efficiency. It would also be desirable to have a thermoelectrochemical device that could be easily and cheaply obtained and that could use common electrolyte materials without causing serious environmental problems.

 (Problems to be Solved by the Invention) According to the present invention, there is provided an apparatus and a method in which reactants in an electrochemical cell are simply and efficiently thermally regenerated. The device is based on the principle that an electric current is generated between a cathode immersed in concentrated acid and an anode immersed in a molten salt solution. Acids and salts consumed by the generation of electric current are regenerated thermally.

 The thermoelectrochemical device according to the present invention basically comprises an electrochemical cell having a cathode compartment and an anode compartment. Both compartments have a common ion-permeable partition. The negative electrode and the positive electrode are in their respective compartments, and can be connected from outside the device to generate voltage and current between both electrodes.

 A catholyte solution consisting of a concentrated aqueous solution of a selected strong Bronsted acid is placed in contact with the cathode in the cathode compartment. During operation of the device, hydrogen gas and first cell reaction products are generated at the cathode and hydrogen ions are consumed. The device is also provided with an anolyte solution of the selected molten salt in contact with the cathode in the anode compartment. Hydrogen gas is consumed during operation of the unit, producing a second cell reaction product.

 A thermochemical regenerator is provided for thermally converting the first cell reaction product formed in the cathode compartment to the acid and intermediate regeneration product selected above. Means are also provided for delivering the catholyte solution from the cathode compartment to the thermal regenerator. Cathode regeneration means are also provided to send the acid formed in the thermal regenerator back to the cathode compartment to replenish the acid consumed during the generation of the current.

 Means for regenerating the molten salt for combining the intermediate regeneration product formed in the thermal regenerator with the second cell reaction product formed in the anode compartment to form a molten salt is also provided. Means for removing heat resulting from this binding reaction are also provided. The salt formed in the binding means is regenerated and returned to the anode compartment to replace the salt consumed during the generation of the electric current.

 If it is desired to operate the thermochemical cell during periods of no heat input to the thermal regenerator, a storage tank may be provided to hold the regenerated electrolyte.

A storage tank may also be provided for accumulating the spent electrolyte until the thermochemical cell is restarted.

 Thermal conversion of the first battery reaction product to the selected acid and intermediate regeneration product, and subsequent formation of the selected salt by combining the intermediate regeneration product and the second cell reaction product. Is a simple, energy-efficient and simple way to constantly replenish the reactants consumed during battery operation, which makes continuous-operation thermoelectrochemical equipment particularly well suited for terrestrial and space applications. Is. The device has no moving parts other than a few small pumps, and thus is expected to operate for a long period of time with little maintenance. The equipment is well suited for use in lowest power cycling cycles and solar combined cycle equipment.

 The features described above and many others, and the attendant advantages of the invention, will become apparent as the invention is better understood upon reading the following examples in conjunction with the accompanying drawings.

EXAMPLES For ease of understanding, the description of the present invention begins with a specific example using phosphoric acid and ammonium phosphate as the working fluid, and then describes more general conditions.

A model of the device according to the invention is shown diagrammatically in FIG. Basically included in the apparatus is an electrolyte battery, generally indicated at 10, a flash stripper 12 and a capacitor 14 for replenishing the reactants consumed in the battery 10 and removing heat. . The electrochemical cell 10 is a conventional electrochemical cell having a cathode compartment 16 and an anode compartment 18. The two compartments are separated by a common ion permeation barrier 20. The partition wall 20 can be an ordinary porous material or a semipermeable membrane that is not attacked by sulfuric acid at 150 ° C. Microporous stoma film without selectivity for wettable porous teflon for any anions and cations are suitable for this purpose, using the cation permeable membrane such as NAFION ^R DuPont is dealing Uno is desirable.

 The electrochemical cell 10 includes a cathode 22 and an anode 24. The cathode and anode must be inert, such as platinum or non-porous palladium-silver alloy electrodes or porous graphite-Teflon platinized fuel cell electrodes, i.e., unaltered or attacked by the electrode reaction. In the latter case, the typical structure contains about 0.25 grams of platinum per parallel foot of electrode and is equipped with a graphite backing plate to allow current collection.

Alternatively, a tantalum net screen for current collection may be provided and lined with a porous Teflon plate. It should be noted that the palladium alloy electrode is also preferable as the electrode for the fuel cell anode because ammonia does not pass through the electrode.

Based on the performance of these various electrodes in known phosphoric acid fuel cells under almost the same operating conditions as those used in the process of the present invention, there is no catalyst poison, so these electrodes require approximately 100,000 hours of maintenance. Expected service life. Electrodes 22 and 24 can be connected to external circuitry (not shown) to generate current and voltage. The external circuit includes a motor and other devices that use the electric energy generated by the battery 10.

Phosphoric acid and its salts are well suited as electrolytes and working fluids for the practice of the present invention because their oxidation state is very stable. Furthermore, they systematically dehydrate to form a series of ortho-, pyro- and metaphosphates. As a mixture of ortho and ammonium pyrophosphate, these form molten salts with low melting points. As the tribasic acid, the three acid dissociation constants of orthophosphoric acid span a wide range of 10 ^-2 to 10 ^-13 at 25 ° C, which is the preferred form for acid concentrating batteries. Since the vapor pressure of ammonia generated from the salt is fairly high, but the vapor pressure of P ₂ O ₅ from the phosphate is quite low, the addition of hydrogen ions to the phosphate groups due to the vaporization of ammonia from the salt is a convenient intermediate. It can be done relatively easily at temperature.

The electrolyte in the cathode compartment 16 shown in FIG. 1 is preferably a molten acid-salt admixture or an aqueous solution of ammonium hydrogen phosphate and phosphoric acid, preferably orthophosphoric acid (H ₃ P O ₄ ), pyrophosphoric acid (H ₄ P ₂ O ₇ ), metaphosphoric acid (HPO ₃ ) _n , and ortho and ammonium hydrogen pyrophosphate represented by NH ₄ H ₂ PO ₄ and NH ₄ H ₂ PO _7. You can

The electrolyte in the anode compartment 18 _{(NH 4) 3 PO 4,} (NH 4) 4 P 2 O 7, (NH 4) 2 HPO 4及beauty ortho- and ammonium pyrophosphate by _{(NH 4) 3 P 2 O} 7 , And a mixture of ortho and ammonium hydrogen pyrophosphate is preferred. The combination of these salts forms a molten salt with a melting point of about 160 ° C. If the cell is used at high discharge rates, ammonium phosphate will form some dihydric salt which is not fully reactive. Orthophosphoric acid, metaphosphoric acid and pyrophosphoric acid and their salts are dehydrated to varying degrees. The ratio of ortho, meta, and pyro can be controlled by adjusting the amount of water in the equipment, which adversely affects the operating performance of the equipment.

One of the key factors in determining the amount of water to be added to the device is based on the transport of water and ammonium ion through the cation exchange membrane used as the cell diaphragm membrane. It is desirable to maintain the mole ratio of water and ammonium ion (H ₂ O / NH ⁺ ₄ ) transfer rate at about 1: 1. This ratio can be achieved if the molten salt in the anode compartment contains at least a 1: 1 molar ratio of water and ammonia ions (H ₂ O / NH ⁺ ₄ ) in the solution.

 As used herein, the term "molten salt solution" refers to a solution consisting of molten salt and a small amount of water. As used herein, "concentrated aqueous solution" refers to a concentrated solution such as concentrated phosphoric acid containing a minimum amount of water.

The amount of water in the equipment should be sufficient to help transfer cell and regenerated products and maintain the fluidity of the equipment. However, the water content should not be so high that evaporation of solvent water in the stripper is reduced and the efficiency of the device is reduced. This aspect of the invention is described in detail below.

 The working fluid in the closed loop system according to the process of the present invention is fully defined by first determining the amount of ammonia, phosphoric acid and water added to the system. Concentrations of these components in each part of the equipment are not specified because these concentrations are automatically determined during operation of the equipment and depend on the design and operating conditions of the equipment. However, in the cathode compartment, the composition of the incoming reactant solution is expected to be more phosphoric acid than ammonium hydrogenphosphate and vice versa for the effluent. In the anode compartment, the influent should be rich in ammonia and ammonium ions and have a low concentration of ammonium monohydrogen phosphate, and the effluent should be the opposite. However, because the anode compartment can operate over a wide range of limits, the effluent can be completely converted to some ammonium hydrogen phosphate. The preferred composition initially added to the device is described below.

 The resistance of the electrical pathways from the electrode 24 through the cell to the electrolyte 18 and from the membrane 20 through the electrolyte 16 to the electrode 22 minimizes internal losses in the device to increase efficiency and maximize current density. It is desirable to keep it small. The following methods are used to minimize resistance. The thickness of the electrolyte compartments 18 and 16 should be minimized, the thickness of the membrane 20 should be minimized, the specific resistance of the electrolyte should be minimized by adjusting the composition, and the appropriate membrane selection and membrane pretreatment process should That is the minimization of the specific resistance. For example, a porous tephron membrane is made permeable by metallic sodium dispersion treatment. Perfluorosulphonate polymer cation exchange membranes are also prepared by well known standard methods for exchange processes depending on the type of electrolyte in which they are used. In the thermodynamic cycle of the present invention, the amount of water used as solvent must be kept fairly low in the cathode loop, otherwise the energy conversion efficiency for water evaporation and condensation over the closed cycle will be significantly higher. Hurt. However, in this device, the ratio of ortho to pyrophosphate of both the acid and its salt by the typical reaction shown in the formula (1) is established in both the anode and cathode compartments for the reasons described above. It requires a small amount of water to help.

Since the anode loop is a condensation loop and is not heated to a high temperature, it seems that the anode loop has more water than the cathode loop. In order to reduce the melting point of the salt mixture and the viscosity of the acid, it is necessary that both ortho and pyrophosphates be present, or both phosphates and water be present together. Water is also required because it catalyzes the collapse of polyphosphate polymer chains and maintains high fluidity. Appropriate amounts of water, phosphoric acid and ammonia can be added to the equipment in the following manner. When adding first working fluid prior to sealing the device, about 1 part (from an aqueous solution of a heavy weight percentage of about 20-100% of _{H 3 PO 4) H 3 PO} 4, about 1-4 parts There is (NH ₄ ) ₂ HPO ₄ , and about 1 part NH ₄ H ₂ PO ₄ . This part is specified on a molar basis. The parts are mixed first and then added to both the anode and cathode compartments. The mixed parts can be preheated before being added to the equipment, taking care that there is no loss of water or ammonia due to heating. Supercooling occurs by heating to about 200-230 ° C before cooling to the device and then cooling to about 150 ° C, which improves fluidity and facilitates filling into the device. 20-100% of H ₃ PO ₄ is a role to supply the required water, the same can have formed Nitsu of water during the heating of orthophosphate later Re this. The exact ratios of salt, salt-to-acid, water-to-salt to acid are determined by the design of the equipment, the desired upper and lower temperature limits, the efficiency of the equipment and the weight of the equipment, the efficiency of the equipment and the volumetric power density of the equipment. And the efficiency of the device and the gravimetric power density of the device. Depending on whether matter what these variables in the design and performance requirements of the device, the overall set configuration of the working fluid, the 0.1-6 parts _{(NH 4) 2HPO 4, NH} 4 H 2 PO 4 of 0.1-2 parts , 0.1-2 parts of 100% H ₃ PO ₄ and 0.1-50 parts of water. The salts, (NH ₄ ) ₂ HPO ₄ and NH ₄ H ₂ PO ₄ , cannot both be 0. The parts mentioned here are on a molar basis. Also, some is supplemented by the conversion of ortho to pyrophosphate, but some water is always needed.

 Typical reactions that take place at the cathode and anode of the device described above are shown in equations (2) and (3) below.

In the cathode, H ₃ PO ₄ + e ⁻ → 1 / 2H ₂ + H ₂ PO ₄ ⁻ (2) In the anode, (NH ₄ ) ₃ PO ₄ + 1 / 2H ₂ → (NH ₄ ) ₂ HPO ₄ + NH ₄ ⁺ + e ⁻ ( 3) Some dibasic salts are also generated when the (NH ₄ ) ₃ PO ₄ is completely reacted. Assuming that a cation-exchange membrane is used to transfer NH ₄ ⁺ from the anode to the cathode, the above two reactions produce a typical net cell reaction shown by the following equation (4). Be done.

(NH ₄ ) ₃ PO ₄ + H ₃ PO ₄ → (NH ₄ ) ₂ H ₂ PO ₄ + (NH ₄ ) ₂ HPO ₄ (4) Similar reactions occur with pyrophosphates, and the net reaction is (5) It is shown by the formula.

_{H 4 P 2 O 7 + (} NH 4) 4 P 2 O 7 → NH 4 H 3 P 2 O 7 + (NH 4) 3 HP 2 O 7 (5) electrochemical cell shown in Figure 1 10 is basically an acid-enriched battery in which the lean side of the battery (ie, the anode compartment) is buffered to minimize mass transfer polarization, which allows it to operate at high power densities. . As can be seen from the reaction on the cathode side in the above formula (2), phosphoric acid in the cathode electrolyte is continuously consumed, and hydrogen gas and ammonium dihydrogen phosphate are constantly generated. In order to maintain the desired phosphoric acid concentration in the catholyte, it is necessary to continually remove the catholyte solution and electrolyte from the cathodic compartment and regenerate the phosphoric acid.

 At the anode, ammonium phosphate and hydrogen gas are constantly consumed, and ammonium monohydrogen phosphate is constantly generated, as shown in the reaction of the above formula (3). To maintain the desired concentrations of ammonium phosphate and ammonium monohydrogen phosphate, constantly remove the anolyte solution and electrolyte from the anodic compartment to reduce the amount of ammonium monohydrogen phosphate in the solution and increase the concentration of ammonium phosphate. Must be processed.

Also, hydrogen gas must be constantly introduced into the anode compartment 18 and in contact with the anode 24. The hydrogen gas generated at the cathode 22 is preferably removed from the cathode compartment 16 and introduced to the anode compartment 18 as indicated by line 26 in FIG. 1 to supply the hydrogen gas required for the cathode half-cell reaction.

 Several of the above cells can be connected in series to generate the desired voltage. If the reverse diffusion of ammonia can be prevented, hydrogen gas from one cell can be directly supplied to the next cell. This can be accomplished by using a pump and manifold system or electrodes that are impermeable to ammonia but permeable to hydrogen, such as silver-palladium alloy electrodes. For example, a practical high power density design using bipolar series stacks can be constructed. One side of the palladium alloy electrode faces the cathode compartment and hydrogen gas is passed through the electrode to the other side facing the anode compartment. The palladium electrode continues to pass ammonia from the cathode compartment to the cathode compartment.

 Two fuel cell electrodes, back-to-back and electrically shorted, likewise carry hydrogen gas in a bipolar stack.

Some ammonia will pass in the opposite direction of the flow. When using cells in a series stack, care must be taken to prevent leakage of electrolyte flow through the solution manifold. For this purpose, a non-conductive electrolyte solution manifold that is long and has the smallest cross-sectional area can be used, or the leakage route can be blocked by an electrolyte dropping supply method. Another way to prevent electrolyte leakage is to run each battery in a batch process so that each cell is filled in sequence. Isolate the cell from the manifold with a non-conductive valve at all times except when filling.

 To regenerate the phosphoric acid contained in the cathode solution, the cathode and cathode solutions are constantly removed from the cathode compartment 16 and anode compartment 18 and the ammonium cations of the phosphate are thermally decomposed to produce liquid phosphoric acid and gaseous ammonia. Heat treatment to form Ammonia gas is separated from the liquid. There are several ways to do this separation, and it is decided taking into consideration the convenience, efficiency and power output. Here are three methods. In the first method shown in FIG. 1, the catholyte solution is preferably sent through line 28 to a heater such as heat exchanger 30, where the solution is mixed with phosphoric acid introduced into the heat exchanger through line 38. It is desirable to exchange heat and heat to a temperature of about 495 ° C. The heated solution is then conditioned by valve 34 and sent to flash stripper 12. The flash stripper is of conventional design and is equipped with heat input means to maintain the flash stripper temperature in the range of 300 ° C to 650 ° C, at which temperature most of the phosphate Sufficient to convert ammonium hydrogen to phosphoric acid and ammonia according to formula (6) below.

NH ₄ H ₂ PO ₄ → H ₃ PO ₄ + NH ₃ (6) Some water vapor must also evaporate with the ammonia gas, and likewise coagulates with ammonia during the reaction of equation (7) below. Must. Ammonia and water are then gravity separated due to the difference in density. In the weightless state like space, centrifugal force and capillary beds are used for separation.

 The heat input 36 is performed by directly collecting solar energy, using a fossil fuel burner, or by secondary heat transfer by a liquid such as liquid sodium or high-pressure steam. It is advantageous to use a direct heat source because all secondary heat transfer methods have inherent losses.

 The phosphoric acid formed in the flash stripper 12 is removed from the flash stripper and reaches the heat exchanger 30 via line 38 where it is cooled below 200 ° C to above about 100 ° C.

The heat removed from the phosphoric acid is transferred into the catholyte solution in the heat exchanger 30 introduced via the line 28 and to a part of the cathode solution in the heat exchanger 30 introduced via the line 42. To be The electrolyte containing the regenerated phosphoric acid is returned from the heat exchanger 30 via line 40 to the cathode compartment 16. Both the catholyte and anolyte solutions should be kept above about 100 ° C so that the viscosity of the solution can be maintained at a sufficient rate to cause the desired electrochemical reaction at the cathode and anode. The temperature of the solution in the cathode compartment is preferably between about 105 ° C and 160 ° C, but may rise to near 200 ° C. The specified temperature of the electrolytic solution may be any value as long as it can maintain satisfactory liquid characteristics in the device.

 Desirably, all migration in the cell is through the ammonium cation and water semipermeable membrane 20. However, if not all of the migration in the cell can be accommodated by the ammonium cations, then it may be necessary to send some of the anolyte solution flow to the flash stripper 12 via lines 42 and 44. Additional phosphoric acid from this substream, which is directed to the flash stripper via lines 42 and 44, is used to replenish the phosphoric acid transferred to anode compartment 16 via lines 38 and 40. If all migration in the cell is solely due to migration of the ammodium cations through the separator wall 20, then valve 46 is closed.

 Ammonia and water formed in flash stripper 12 are directed to condenser 14 via line 48. In the condenser 14, ammonia and water react with the anolyte solution and are discharged from the anodic compartment via line 50. Valves 52 and 54 are provided to moderate the flow of the reaction stream into the condenser 14.

The capacitor 14 acts as a coupling means, in which ammonia reacts with ammonium dihydrogen phosphate to form ammonium phosphate by the reaction represented by the formula (7).

NH ₃ + (NH ₄ ) ₂ HPO ₄ → (NH ₄ ) ₃ PO ₄ (7) Ammonium phosphate formed in the condenser 14 is suitable for the radiator and the heat exchanger indicated by the arrow 56 in FIG. It is cooled to about 100-130 ℃ by the method. The combination of reactants and heat exchangers just described can be realized in a simple way, such as by condenser 14, or the coupling means and heat exchange means can be provided separately. In the latter case, some of the cooled solution must be returned to the coupling means to prevent an abnormal temperature rise inside. The anolyte solution containing the regenerated ammonium phosphate is led through the condenser 14 via line 58 to the anode compartment 18 to supplement the ammonium phosphate consumed during the operation of the system.

 The apparatus is provided with pumps 55 and 57 for pressurizing the apparatus and circulating various solutions. Pressures of 5-400 psia (34-2760 kPa) can be used.

In the device described here, the vapor pressure is higher on the anode side of the cell than on the cathode side. Passage of ammonia from the anode to the cathode side should be avoided except for the electrochemical transfer of ammonium ions.

Therefore, the two ammonia connections shown at 26 and 20 in Figure 1 must be blocked. Since hydrogen flows in the direction opposite to that of ammonia in the line 26 which is a connection path for hydrogen gas, a pump or turbine may be provided in the line 26 to block all the flow of ammonia. Regarding the blockage of the separation membrane 20 which is the secondary connection, this separation plate can be a perfluorinated sulfonic acid membrane which is extremely impermeable to gas. On the other hand, the pressure created by pumps 55 and 57 must be kept just below the temperature of the stripper and high enough to suppress boiling of ammonia in heat exchanger 30. At 100-200 ° C, the pressure is high enough to dissolve ammonia as NH ₄ ⁺ ions in the electrolyte, so simple microcavity membranes such as wettable porous Teflon cannot be used. If a porous fuel cell electrode is used, the pressure of hydrogen gas in line 26 should be such that lines 38, 42, and 50 of the hydrogen gas line should be such that the electrolyte boundary is within the wetted side of the porous fuel cell electrode. It must be maintained at the same pressure as in. For this reason, it is preferred to use the previously mentioned porous Teflon-lined fuel cell electrodes.

 400 psia (2760 kPa) in lines 50, 28, 32, 42, 26 and 44 in the cell and in heat exchanger 30 to prevent boiling in equipment where boiling is not preferred. High pressure is maintained. The efficiency of the device can also be maximized thanks to the absorption of all heat at the upper temperature limit.

The specified pressure used depends on the pressure of the ammonia and water vapor, which depends on the composition of the working fluid initially charged to the equipment, and the upper and lower temperature limits of the equipment. The vapor phase of the device according to the invention comprises ammonia, water vapor, a small amount of phosphoric oxide, optionally with nitrogen optionally added. Low pressure hydrogen is present in line 48 and stripper 12 and capacitor 14. The partial pressures of ammonia and water vapor can each be varied in the range of about 1 to 300 psia (7-2068 kPa), while the partial pressure of nitrogen can only be varied in the range of about 0 to 150 psia (1034 kPa). A conventional controller can be provided to control the pumps and valves to obtain the desired differential pressure across the membrane 20. This differential pressure must be close to zero to maintain forced heat transfer through the membrane 20 within desired limits.

 FIG. 2 shows a second method for thermal regeneration of cell reactants by multistage ammonia separation using flow in opposite directions. Although more complicated, this method can separate more of the ammonia from phosphoric acid, which can generate higher voltage and increase efficiency. For convenience, when the same elements as in FIG. 1 are also shown in FIG. 2, they are designated by the same numbers as in FIG.

 In this multi-stage system, shown in FIG. 2, the fluid from the anode compartment is heated to about 500 ° C. before being sent to the flash stripper 60. The high-pressure ammonia produced by the high-pressure stripper is led via line 62 to a condenser 64, where the largest amount of ammonium monohydrogen phosphate is converted to ammonium phosphate. A mixture of partially converted phosphoric acid and ammonium dihydrogen phosphate in stripper 60 enters stripper 70 via line 66 via valve 68 where it is conducted from the cathode compartment via line 32 and valve 72. Combines with the preheated stream that has been burned. At a lower pressure than stripper 60, further ammonia is expelled here. This ammonia is led via line 74 to capacitor 76, where an intermediate amount of ammonium monohydrogen phosphate is converted to ammonium phosphate. The liquid from stripper 70 is then directed to capacitor 84 via line 78 and valve 52. Since the pressure of the ammonia in the condenser 84 is relatively low, ammonia is further extracted from the liquid in the stripper 82 via the line 86. As a result, the liquid exiting stripper 82 through line 38 is substantially free of ammonia.

 Heat is supplied to the three strippers 60, 70 and 82 through coils 88, 90 and 92 to maintain high temperatures. The pressure is controlled by the setting of valves 46, 68, 72, 80 and 52. Pumps 94 and 96 are used to increase the pressure and circulate fluid through capacitors 76 and 64. Water and other fluids are circulated through the capacitors 84, 76 and 64 to remove heat and maintain their temperature at about 130 ° C. Other methods can be used to remove heat.

It is noted that the number of strippers used can be more or less than three depending on the degree of separation desired and the limitations of complexity. Also, if all transfer is by ammonium ions (NH ₄ ⁺ ), stripper 60 and capacitor 64 are not needed and valve 46 is closed.

 Figure 3 shows a third method of thermal regeneration by removing ammonia in multiple stages using a cross flow. In this device, two concentrations of ammonium phosphate are formed, which would require separate manifolds to enter the multi-stage battery. The voltage will be slightly different for the two streams, but the usual way is to change the output voltage by varying the number of cells using each stream.

 In the description of FIG. 3, the same components as in FIG. 2 are designated by the same numbers as in FIG. In FIG. 3, the fluid from the anode compartment is heated to high temperature by the heat exchanger 30 and fed to the flash stripper 60 via valve 46. The high-pressure ammonia produced by this stripper is sent via line 62 to a condenser 64 where it is converted into as much ammonium monohydrogen phosphate and ammonium phosphate as possible. The partially converted phosphoric acid and ammonium dihydrogen phosphate in stripper 60 are then sent via line 66 to stripper 70 via valve 68 where they are preheated from the cathode compartment via line 32 and valve 72. Combine with the flow. Since the pressure is lower than that in the stripper 60, further ammonia is discharged.

Ammonia passes via line 74 to capacitor 76 where a smaller amount of ammonium monohydrogen phosphate is converted to ammonium phosphate. The fluid from stripper 70 is then discharged through line 38, which is substantially free of ammonia. On the other hand, spent fluid from the anode is directed through line 31 and split into streams 1 and 2.

Stream 1 is led via valve 52 to condenser 64 where as much ammonium monohydrogen phosphate as possible is converted to ammonium phosphate. Fluid is pumped from capacitor 64 by pump 94 via line 95 toward the anode compartment of the cell. The regenerated fluid from this capacitor 64 produces a relatively high voltage in the cell in which it is used. The spent fluid in the anode compartment from line 31 is transferred via valve 53 to condenser 76 at a lower pressure than condenser 64. In the capacitor 76, ammonium monohydrogen phosphate forms less ammonium phosphate than was formed in the previous capacitor 64, and the conversion product is then pumped by the pump 96 toward the anode compartment of the cell. The regenerative fluid from this capacitor 76 produces a lower voltage than that from the capacitor 64 in each cell in which it is used.

 Heat is supplied to strippers 60 and 70 from coils 88 and 90 to maintain temperatures in the range of about 300-650 ° C. The pressure is adjusted by setting valves 46, 68, 72, 52 and 53. Pumps 94 and 96 are used to boost and circulate fluid through capacitors 64 and 76. Water or other fluid is circulated through capacitor 64 to remove heat and maintain the temperature at about 130 ° C. Other methods of heat removal can also be used.

It should be noted that the valve 46 can be closed if all transfer in the cell is done by ammonium ions (NH ₄ ⁺ ).

In this case, some of the fluid from line 32 is sent to stripper 60 via valve 43.

 It should also be noted that for ammonia some ammonia can be lost at the anode. Hydrogen is selectively oxidized to ammonia, but very small streams can also occur, indicating a slow oxidation of ammonia to nitrogen. Extremely slow ammonia oxidization is expected.It is not possible to automatically inject a small amount of replacement ammonia from a small liquid ammonia storage tank if it is harmful before the end of the device's life. It's easy. Nitrogen generated by the oxidation of ammonia may be left as it is or discharged. When using a silver-palladium alloy electrode, nitrogen may collect in the condenser part of the device and be automatically discharged. If fuel cell electrodes were used, nitrogen would collect in the hydrogen supply line to the anode, which would be more difficult to vent.

 Energy storage of the above-mentioned device can be considered because the electrochemical cell can be operated during periods when there is no heat input to the thermal regenerator. To do this, insert regenerated electrolyte storage tanks 100 and 102 into lines 58 and 40 of the device, as shown in FIG. 4, which is a systematic diagram of a portion of the device shown in FIG. Good. The electrolyte stored in these tanks can then be fed into the cell while the thermal regenerator is not working. Furthermore, when the thermal regenerator is not operating, spent electrolyte from the cell is placed in tanks 104 and 106, which are located in lines leading to 50, 42, and 28 as shown in FIG. Can be stored in When the thermal regenerator starts operating again, the spent electrolyte is regenerated and stored again in the original regenerated electrolyte tank. With proper selection of tank, cell and thermal regenerator sizes, the cell can maintain continuous operation even if the regenerator operates intermittently. This type of device is suitable for use when there are changes in the load of light, such as changes in sunlight at night, changes in the degree of being blocked by clouds, and so on.

 The valves 34, 46 and 52 shown in Figures 1-3 can be replaced by turbines to extract energy at these points where the fluid experiences a significant pressure drop. This amount of energy is very small compared to the energy of the device and is approximately equal to the energy used for the two pumps 55 and 57.

 Regarding the material of the structure shown in Fig. 1, it should be noted that phosphoric acid is extremely corrosive above 350 ° C, and many materials such as ceramics and graphite are attacked by phosphoric acid above 350 ° C. I have to. In our corrosion test, graphite and gold are not attacked by ammonified 100% phosphoric acid at 500 ° C, but phosphoric acid resistant superalloys (ie alloys with high nickel content) are attacked to some extent. Other metals such as copper or silver, alloys of copper or silver, and some other alloys are also known to be extremely resistant to phosphoric acid. Therefore, an efficient heat exchanger can be constructed using this type of corrosion resistant metal.

However, some metals are catalysts that decompose ammonia into water and hydrogen, so care must be taken.

However, in the case of molybdenum, this decomposition is extremely slow, and it may take 5-10 years to decompose 10% of the ammonia in the equipment, based on many published data. Therefore, molybdenum and molybdenum (TZM) containing a small amount of zirconium and titanium are good metals as structural materials for heat exchangers and strippers as shown in FIG. Various materials, including various metals, graphite, ceramics, and various polymers, are suitable for constructing the parts of the equipment used below 200 ° C shown in Fig. 1.

 An extremely simple closed cycle was constructed to ensure that there are no dissipative side reactions in the steady state operation of the entire closed system of the present invention. The device is not designed to measure efficiency or operate at high current densities, but simply in steady state to ensure that the reactants needed to operate an electrochemical cell are thermally regenerated. All you have to do is drive. The equipment used is shown in FIG. No attempt was made to retain the ammonia from the cathode side, except that the liquid surface boundary area was reduced to absorb ammonia. To do this, a simple method was to make the differential pressure on both sides of the fritted glass separator zero. The generated voltage decreased because the ammonia from the cathode could not be blocked.

In the following description of FIG. 5, components corresponding to those shown in FIG. 1 are numbered the same as in FIG. As shown in FIG. 5, the cell 10 includes a platinum plate cathode 22 and a platinum wire mesh anode 24. Electrodes 22 and 24 were connected to an external load, not shown. The electrolyte in the cathode compartment 16 was a mixture of ammonium dihydrogen phosphate and ammonium phosphate. The electrolyte mixture in the anode compartment 18 was initially the same as in the cathode compartment. When the device is operated, ammonia and water from stripper anode mixture _{(NH 4)} 2 HPO ₄ were diluted enriched _H 3 PO _4. The frit glass disk served as the separator 20.

 The spent electrolyte from cell 10 was sent by pump 57 through line 28 to stripper 12. Around the stripper 12, a heating mantle 36 provided heat for the stripping reaction.

Ammonia was formed when the spent electrolyte contacted the hot stripper wall. Ammonia generated by the stripping reaction was sent via line 48 directly to the anode compartment 18, where ammonia was absorbed in the solution. The phosphoric acid, which was also generated in the stripping reaction, was returned to the cathode compartment 16 via line 40 by pump 57. Hydrogen generated at the cathode 22 bubbled up and reached the anode compartment 18 via line 26 where it was consumed. The flow from the cathode compartment 16 and the anode compartment 18 was determined by setting valves 34 and 46. A pressure gauge 49 was used to monitor the pressure inside the device. The device was filled with hydrogen using valve 51 and then closed. Prior to filling the device with hydrogen, valve 53 was operated to expel air. The voltage and current were measured by applying a load with the lead wires attached to the anode 24 and the cathode 22.

 The following simplifications were made in order to facilitate the closed loop system demonstration experiment using the device in Fig. 5.

 a. The heat exchanger was omitted.

 b. Due to the small size of the device, it was not necessary to remove heat during the ammonia condensation stage. Therefore, the gas generated in the stripper was directly guided to the anode compartment of the cell, eliminating the need for a separate capacitor. In fact, external heat had to be applied to keep the device at working temperature.

 c. The molybdenum stripper was fitted with a cooling coil at either end for overheat protection.

 d. The platinum wire network used as the anode electrode was an extremely low current density electrode. Pure platinum was used to ensure that no secondary reactions occur.

 e. The flow rate of the pump was kept large in order to minimize the time to reach steady state.

When a 2.2 ml / min flow rate was combined with a device volume of about 150 ml, the residence time was about 68 minutes.

 The parameters investigated were the regenerator upper temperature limit, the total equipment pressure, and the hydrogen to ammonia ratio in the gas phase. The measured values were cell temperature, stripper temperature, output current and IR (current x resistance) correction voltage. By performing IR correction, it was possible to avoid the effects of the positioning of the electrodes and the resistance of the porous frit separator. A typical experimental procedure was performed as follows.

 1. The device was evacuated to about 1 mm Hg.

 2. The working fluid mixture, for example as follows, was added to the device:

100% _H 3 _PO 4 -95 mol% _{(NH 4) H 2 PO 4} -5 mole percent 3. The pump was started to stabilize the liquid level in all parts of the device.

 4. The regenerator was heated and the auxiliary heating device was started. The refrigerant pump was started.

 5. Ammonia and water were added to the desired working pressure.

 6. The cell was adjusted to obtain the desired output. The voltage was monitored and stabilized.

 7. The operating parameters (eg stripper temperature, flow rate, pressure, current, etc.) were changed to stabilize the device under new conditions.

 Experimental output data for various operating conditions are shown in Table I. In Table I, "OCV" indicates the release voltage, "Voltage" indicates the voltage obtained at the specified current load, and "Time" indicates the length of time the device has been running.

As you can see from this data, the maximum power output is The cell temperature was 154 ℃ and the stripper temperature was 265 ℃. Working fluid in operation 1 and 3, of 95 mol% _H 3 PO ₄ and 5 mole% of _NH 4 _H 2 - was a mixture of PO _4. For a mixture of 95 mol% at the operating 2 _H 3 PO ₄ and 5 mole% _{NH 4 H} 2 PO 4, significant amounts of ammonia gas were added.

 Different amounts of water were incorporated by employing different phosphoric acid concentrations as shown in Table II.

Hydrogen was added so that the total pressure was 1 atm (0 psig) in Runs 1 and 3, and 3 psig or 21 kPa gauge in Run 3. The pressure of ammonia and water vapor was estimated to be 300 mmHg in operation numbers 1 and 3.

 For run numbers 1 and 3, the equipment circulation time was taken to be well above 68 minutes to ensure steady state operation. It seems that the operation was in the steady state in the operation number 2, but the two input flows were mixed after 20 minutes due to the pressure fluctuation of the device.

 It should be noted that the description of the experiments presented here is merely intended to demonstrate closed-loop operation and does not represent optimum operating conditions.

In addition to the above-mentioned experimental demonstration of the thermo-electrochemical device of the present invention, further experimental tests were carried out to support the effectiveness and practicality of the device of the present invention. A device with a cathode compartment in one breaker and an anode compartment in the other breaker, with a connecting salt bridge with a Teflon valve that opens slightly during measurement, at 0.510 at 155 ° C. The release voltage of the bolt was obtained. A solid platinum electrode and a 100% strength phosphoric acid negative electrode solution and an (NH ₄ ) ₃ PO ₄ anolyte solution in (NH ₄ ) ₃ HPO ₄ were used. The hydrogen gas pressure was maintained at 1 atm in the cathode compartment and about 0.5 atm in the anode compartment. Therefore, this data represents an undesired experimental condition in which migration is not limited to ammonium cations only. Had a cation exchange membrane been used, the migration would have been guaranteed to be primarily due to ammonium cations. As a result of measuring the release voltage with respect to temperature, the heat of regeneration (enthalpy) by the Gibbs-Helmholtz equation was experimentally obtained. The experimental value of heat energy input was 23.7 kcal / equivalent. From the measured OCV, the calculated electrical energy output was 11.8 kilocalories / equal. Using the following formula, the calculated efficiency (η) is 50%.

 η = Electrical electrical energy / Input thermal energy Experimental data also show the effectiveness of the heat exchange process necessary for practicing the invention. Using the data in the literature investigating the relationship between temperature and the vapor pressure of ammonia from ammonium dihydrogen phosphate, integrating the Claujueus-Claveilon equation using this data, between 150 ° C and about 550 The specific heat of ammonium dihydrogen phosphate is equal to that of ammonia plus phosphoric acid between 150 ° C and about 550 ° C. Therefore, in the practical application of the present invention, excellent heat exchange is performed between ammonium dihydrogen phosphate heated to about 550 ° C. and phosphoric acid and ammonia cooled to about 150 ° C. You will be able to break. Moreover, as a result of further heat transfer calculations, even with all actual losses taken into account, a high efficiency of 40% at a power density of 300 w / kg or 80% at the Carnot cycle can be achieved. Although the total weight of the heat engine equipment shown in Fig. 1 is taken into consideration, the weight of the receiver and radiator is not taken into consideration.

Finally, experimental data indicate that the kinetics are favorable for the desired reactions to occur in the practice of the invention. Since the polarization values of fuel cell electrodes in phosphoric acid at 150-200 ° C are almost the same for both the cathode and the anode, the cathode polarization loss in a platinum plate is 100% phosphoric acid at 150 ° C for 100% phosphoric acid and 100% ammonium dihydrogen phosphate. Compared. At an overpotential of 112 mV, a current of 784 ma / cm ² was obtained with 100% phosphoric acid, compared with 204 ma / cm ² with 100% diammonium hydrogen phosphate. The results show that the kinetics of ammonium phosphate is almost as fast as the kinetics of the phosphoric acid fuel cell power plant hydrogen electrode (capable of operating 1 A / cm ² with only 50 mV loss). There is. In particular, this result suggests that the data for Pd-Ag, where ammonia absorption cannot occur on the gas side, is very similar to that for phosphoric acid compared to the ammonium phosphate electrode.

 The equipment described above has the capacity to operate at a high Carnot rate of 77% between 100 ° C and 500 ° C. The operating temperature range makes the device useful as a bottoming cycle in a single cycle heat engine or a combined cycle converter. The device can be combined with topping cycles such as air Brayton, thermionic anergy conversion, and sodium heat engine. Also, because the device is safe and environmentally sound, solar heat conversion, energy conversion in the electric power industry, space energy conversion, geothermal energy conversion, nuclear energy conversion, remote energy conversion, silence energy conversion, and other It can be used for a wide range of applications, including numerous applications.

 Looking at the above embodiments of the invention in a more general sense, the following features of the invention are noted.

a) The working fluid in the cathode compartment consists of concentrated phosphoric acid. During the reaction of the cell, hydrogen ions from phosphoric acid are consumed and hydrogen and H ₂ PO ₄ ⁻ are generated.

NH ₄ ⁺ ions also mix into the cathode compartment through the cation permeable membrane.

 b) The working fluid in the anode compartment consists of the ammonium phosphate salt in molten form with some water content.

During the reaction of the cell, phosphate ions from the salt reduces the concentration of hydrogen ions in the anode compartment occurs hydrogen and HPO ₄ ^-2 reacts with hydrogen ions. Therefore, the phosphate ion keeps the hydrogen ion concentration low on the side of the cell where the concentration is low (that is, the anode compartment).

 c) To continue the operation of the cell, the reaction products of the cell must be removed from the cell and placed in process conditions where the starting materials for the anode and cathode compartments are regenerated.

d) Phosphoric acid for the cathode compartment is regenerated by direct thermal decomposition of the (NH ₄ ) ₂ HPO ₄ reaction product formed in the cathode compartment.

e) The (NH ₄ ) ₂ HPO ₄ reaction product of section “d” above also produces ammonia and water. The ammonia and water react with the (NH ₄ ) ₂ HPO ₄ reaction product formed in the cathode compartment to form (NH ₄ ) ₃ PO ₄ , the starting material for the positive compartment.

 Although a more detailed description has been given of more preferred embodiments of the invention where the working fluid is phosphoric acid and molten ammonium phosphate salt, the invention is not limited to these particular working fluids. In view of the general description just given above, a working fluid suitable for use in the present invention can be characterized as follows. The catholyte solution is an aqueous solution consisting of a minimum amount of water and concentrated strong Bronsted acid (pKa, 3 or less), which can provide the hydrogen ion concentration for generating a required voltage. Also, during the cell reaction, the anion portion of the acid must be able to combine with the cell reaction product from the anode to form an intermediate decomposition product. This intermediate decomposition product must then be able to combine with the cell reaction product from the anode to form the starting material for the anodic reaction. The anolyte solution consists of a relatively low melting point (ie 20-200 ° C) molten salt containing a small amount of water. The negative ion portion of the salt must be capable of undergoing reactions that reduce the hydrogen ion concentration in the anode compartment. The cation portion of the salt can move from the anode compartment through the membrane to the anion compartment and combine with the anion product formed in the cathode compartment to thermally decompose the acid, resulting in It must be able to form a product.

 This completes the description of the exemplary embodiments of the present invention, but those skilled in the art will understand that the announcements made in the exemplary embodiments are merely examples, and that various other alternatives, applications, and variations are not possible. It must be noted that it is within the scope of the invention. Therefore, the invention is not limited to the specific embodiments described herein.

[Brief description of drawings]

 FIG. 1 is a systematic diagram showing a preferred exemplary embodiment according to the present invention. FIG. 2 is a systematic diagram of a second alternative method for ammonia regeneration according to a preferred exemplary embodiment of the present invention. FIG. 3 is a systematic diagram of a third alternative method for ammonia regeneration according to a preferred exemplary embodiment of the present invention. FIG. 4 is a systematic diagram showing a part of the method of FIG. 1 in which a storage tank for used electrolyte and regenerated electrolyte is used. FIG. 5 is a systematic diagram showing the set-up of an experiment for conducting a closed-loop test according to a preferred exemplary embodiment of the present invention. 10 ... Electrochemical cell, 12 ... Flash stripper, 14 ... Condenser, 16 ... Cathode compartment, 18 ... Anode compartment, 22 ... Cathode, 24 ... Anode, 30 ... Heat exchanger, 100, 102 ... Storage tank

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[Procedure amendment]

[Submission date] Hei 1.10.19 (1) Amend the claims as shown in the attached sheet. (2) "(Problems to be solved by the invention)" on page 14, line 8 of the description is corrected to "(Means for solving the problem)". (3) “The reaction product is formed.” On page 15, line 9, of the specification.
Is corrected to "the reaction product occurs at the anode." (4) In the description, page 30, line 3 to line 4, "cathode or anode solution" is corrected as "cathode solution or cathode solution and anode solution". (5) Replace Figures 2 and 3 with the accompanying Figures 2 and 3.

[Claims]

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Claims (19)

[Claims] 1. A thermoelectrochemical device for generating an electric current, comprising: a) an electrochemical cell having a cathode compartment and an anode compartment and having a partition common to both compartments; and b) in each compartment. An anode and an anode that allow external connection of the battery to generate an electric current; and c) a selected strong Bronstead acid present in contact with the cathode in the cathode compartment. A catholyte solution consisting of a concentrated aqueous solution, in which hydrogen ions are consumed during the generation of an electric current to generate hydrogen gas and first cell reaction products; and d) present in the anode compartment in contact with the anode. It consists of a selected relatively low melting point molten salt solution, and the anion of the salt reacts with hydrogen gas to reduce the hydrogen ion concentration in the anode compartment to form a second cell reaction product. In addition, the cations of the salt are decomposed by heat. And a thermochemical regenerator for thermally converting the first cell reaction product to the selected acid and intermediate regeneration product, and f). Means for transferring the catholyte solution containing the first cell reaction product from the cathodic compartment to the thermochemical regenerator; and g) removing the selected acid formed in the thermochemical regenerator. Negative electrode regeneration means for replenishing the selected acid that is transported to the cathode compartment and consumed during the generation of the current; h) the second cell reaction product from the anode compartment and the The means for forming the molten salt by combining with the intermediate regeneration product from the chemical regenerator, i) means for removing heat generated as a result of the combining in the step h, and j) the heat. Transfer the intermediate regeneration product generated in the chemical regenerator to the coupling means K) means for transferring the anolyte solution containing the second cell reaction product to the binding means, and l) transferring the molten salt produced in the binding means to the anode compartment. A thermoelectrochemical device comprising an anode regeneration means for replenishing the molten salt consumed during the generation of an electric current. 2. The thermoelectrochemical apparatus according to claim 1, further comprising means for sending hydrogen gas generated in the cathode compartment to the cathode compartment for consumption at the anode during the generation of electric current. 3. The acid is sent to the cathode compartment and the molten salt is sent to the anode compartment between the selected acid in the thermochemical regenerator and the molten salt generated in the coupling means. The thermoelectrochemical device according to claim 1, further comprising a storage tank for separately storing before being stored. 4. A cathode solution containing the first cell reaction product and an anolyte solution containing the second cell reaction product, wherein the cathode solution is supplied to the thermochemical regenerator means. The thermoelectrochemical device of claim 1 including a storage tank for separating and storing the solution before it is sent to the coupling means. 5. A thermoelectrochemical device according to claim 1, wherein the means for removing heat is associated with the coupling means. 6. The thermoelectrochemical device according to claim 1, wherein the anode and the cathode are inert electrodes. 7. The thermoelectrochemical device according to claim 1, wherein a plurality of the electrochemical cells are connected in series. 8. A thermoelectrochemical device for generating an electric current, comprising: a) an electrochemical cell having a cathode compartment and an anode compartment, both compartments having a common ion-permeable partition; and b) each said compartment. A cathode and an anode, which are placed inside and allow an external connection of the battery for the generation of an electric current, and c) consisted of a concentrated aqueous solution of phosphoric acid in contact with the cathode in the cathode compartment during the generation of an electric current. And a cathode solution in which hydrogen gas and ammonium dihydrogen phosphate are generated at the cathode to consume phosphoric acid, and d) a molten salt solution of ammonium phosphate and / or ammonium monohydrogen phosphate in contact with the anode in the anode compartment. And an anode solution in which ammonium phosphate and hydrogen gas are consumed in the anode during the generation of an electric current to generate ammonium monohydrogen phosphate or monohydrogen phosphate and ammonium dihydrogen. E) a thermochemical regenerator that thermally converts the ammonium dihydrogen phosphate generated in the cathode compartment into phosphoric acid and ammonia; and f) a cathode solution containing the ammonium dihydrogen phosphate from the cathode compartment. Means for transferring to said thermochemical regenerator, g) sending phosphoric acid formed in said thermochemical regenerator to said cathode compartment, cathodic regeneration for replenishing phosphoric acid consumed during the generation of current Means for removing heat from the phosphoric acid formed in the thermochemical regenerator and transferring this heat to the transferred catholyte solution; and i) combining ammonia with ammonium monohydrogen phosphate. An ammonium phosphate regenerator that produces ammonium phosphate and condenses water vapor; j) the ammonium and hydrogen phosphate generated for binding and reaction of ammonium and water generated in the thermochemical regenerator with ammonium monohydrogen phosphate. And (k) means for transferring an anolyte solution containing ammonium monohydrogen phosphate to the ammonium phosphate regenerator for binding and reaction with ammonia to form the ammonium phosphate, l). A thermoelectrochemical device comprising: an anode regeneration means for transferring ammonium phosphate formed in the regenerator to the anode compartment and replenishing ammonium phosphate consumed during generation of an electric current. 9. The thermochemical regenerator means heats the catholyte solution to a temperature of about 300 to 650 ° C. to thermally convert ammonium dihydrogen phosphate into phosphoric acid and ammonia, and ammonia to phosphoric acid. The thermoelectrochemical device according to claim 7, comprising means for separating from ammonium dihydrogen. 10. A working fluid comprising 0.1 to 6 parts ammonium monohydrogen phosphate, 0.1 to 2 parts ammonium dihydrogen phosphate, 0.1 to 2 parts phosphoric acid, and 0.1 to 50 parts water on a molar basis. The thermoelectrochemical device according to claim 8, which is provided. 11. The thermoelectrochemical device according to claim 8, wherein the anode and the cathode are made of a material selected from platinum, palladium, a palladium-silver alloy, and a porous graphite-Teflon platinum-plated fuel cell electrode. . 12. The pressure in the system is about 5 to 400 psi (34 to 2 psi).
The thermoelectrochemical device according to claim 8, which is 760 kPa). 13. A thermoelectrochemical device according to claim 8, wherein the means for removing heat is combined with the ammonium phosphate regenerator means. 14. A method for generating an electric current between an anode and a cathode, comprising: a) contacting the cathode with a catholyte solution consisting of concentrated phosphoric acid aqueous solution, said cathode and catholyte solution being placed in a cathodic compartment; The cathode compartment has an ion-permeable partition in common with the anode compartment, b) contacting the anode with an anolyte solution in said anodic compartment, said anolyte solution from a molten salt solution of ammonium phosphate and / or ammonium monohydrogen phosphate The anode and cathode can be connected because they generate a current between both electrodes, and hydrogen gas and ammonium dihydrogen phosphate are generated at the cathode during current generation, phosphoric acid is consumed, and during the generation of current, the anode Ammonium phosphate and hydrogen gas are consumed to generate ammonium monohydrogen phosphate or monohydrogen phosphate and ammonium dihydrogen, c) hydrogen gas is introduced into the anode compartment, and d) dihydrogen phosphate. Removing the catholyte solution containing ammonium from the cathodic compartment; e) thermally converting the ammonium dihydrogen phosphate in the removed catholyte solution into phosphoric acid, ammonia, and water; Heat from the phosphoric acid is transferred to the removed catholyte solution containing ammonium dihydrogen phosphate, and g) the thermally formed phosphoric acid is transferred to the catholyte solution to replenish the phosphoric acid consumed during the generation of current. H) removing the anolyte solution containing ammonium monohydrogen phosphate from the anodic compartment, and i) reacting the ammonium monohydrogen phosphate in the removed anolyte solution with ammonia to thermally convert ammonium dihydrogen phosphate to phosphoric acid. The water produced during the conversion is condensed to form ammonium phosphate, and j) the ammonium phosphate produced by the reaction of ammonium monohydrogen phosphate with ammonia is transferred to the anodic compartment. Method of generating a current between the anode and cathode which comprises replenishing the phosphate ammonium um consumed during generation of the flow. 15. The ammonium dihydrogen phosphate is thermally converted in the removed catholyte solution by heating the ammonium dihydrogen phosphate to at least about 300 ° C., wherein the ammonium dihydrogen phosphate is converted to phosphoric acid and ammonia. 15. The method of claim 14, which is transformed. 16. The method according to claim 14, wherein the hydrogen gas generated at the cathode is removed from the cathode compartment and introduced into the anode compartment for reaction at the anode. 17. The method of claim 14, wherein the anode and cathode are inert electrodes. 18. The method of claim 14, wherein the temperature of the anolyte solution and the catholyte solution is maintained at least 100 ° C. or higher. 19. An operation of the apparatus comprising on a molar basis 0.1 to 6 parts ammonium monohydrogen phosphate, 0.1 to 2 parts ammonium dihydrogen phosphate, 0.1 to 2 parts phosphoric acid, and 0.1 to 50 parts water. The method according to claim 14, wherein a fluid is used.