Fuel cell system based on solid hydrogen pool and hydrogen-electricity conversion efficiency determination method

Abstract

The invention relates to the technical field of energy power, in particular to a fuel cell system based on a solid hydrogen pool and a hydrogen-electricity conversion efficiency determination method. The fuel cell system comprises a solid hydrogen pool module, a fuel cell module and a coupling module which are integrally assembled, the solid hydrogen pool module comprises a hydrolysis hydrogen releasing pool and a solid hydrogen storage component, the fuel cell module comprises an electrolytic tank and a proton exchange membrane, and the coupling module comprises a hydrogen conveying unit and a water circulation unit. The hydrogen conveying unit is used for conveying hydrogen released by the solid hydrogen storage component into the electrolytic tank for electrochemical reaction, and the water circulation unit is used for extracting an aqueous solution containing unelectrolyzed hydrogen in the electrolytic tank into the hydrolysis hydrogen release tank for hydrolysis hydrogen release reaction. The hydrogen element in the aqueous solution can be recycled for the second time in the hydrolysis hydrogen release tank and the electrolytic tank, so that the double hydrogen production effect is achieved, and the energy storage and hydrogen-electricity conversion efficiency is greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of energy and power technology, and in particular to a fuel cell system based on a solid hydrogen pool and a method for determining hydrogen-to-electricity conversion efficiency. Background Art

[0002] Hydrogen energy is a renewable secondary energy source. Due to its large reserves in the universe, it is considered an important resource for solving the future energy crisis. With the continuous reduction of fossil energy and the continuous increase in pollution, hydrogen energy is known as a clean and good carrier that can replace traditional energy. Its products in the energy conversion process are pollution-free, highly environmentally friendly, and have high energy conversion efficiency. Especially in the fields of transportation and power generation and energy storage, as an alternative to traditional fossil energy, it provides a steady stream of electricity and heat energy for the transportation and thermal power fields, making hydrogen energy play a key social role. However, due to many influencing factors such as the low density of hydrogen at room temperature and pressure, the high energy consumption of pressurized storage of hydrogen, and the high cost of long-distance transportation, the technological development of hydrogen energy has been seriously affected.

[0003] Hydrogen is used as an energy source, mainly converted into electrical energy through fuel cells. The methods for improving the hydrogen-to-electricity conversion efficiency of traditional fuel cell systems mainly include improving catalyst performance, increasing membrane electrode efficiency, and reducing fuel cell accessory power consumption. However, due to the polarization internal resistance of electrochemistry, especially in the rated power and high current density area, the hydrogen-to-electricity conversion efficiency of traditional fuel cell systems is generally between 40% and 60%, and the limit cannot be higher than 60%. In other words, it is difficult to improve the hydrogen-to-electricity conversion efficiency of traditional fuel cell systems, and in the transportation of hydrogen, the transportation efficiency of high-pressure hydrogen is low. Summary of the invention

[0004] The technical problem to be solved by the embodiments of the present invention is to provide a fuel cell system based on a solid-state hydrogen pool and a method for determining the hydrogen-to-electricity conversion efficiency, so as to solve the problems in the prior art that the hydrogen-to-electricity conversion efficiency of the fuel cell system is difficult to improve and the high-pressure hydrogen transportation efficiency is low.

[0005] The present invention discloses a fuel cell system based on a solid-state hydrogen cell, comprising an integrated solid-state hydrogen cell module, a fuel cell module and a coupling module, wherein the solid-state hydrogen cell module comprises a water-extracting hydrogen cell and a solid-state hydrogen storage component arranged in the water-extracting hydrogen cell, the fuel cell module comprises an electrolytic cell and a proton exchange membrane arranged in the electrolytic cell, the proton exchange membrane separates the electrolytic cell into an anode chamber and a cathode chamber, and the coupling module comprises a hydrogen transmission unit and a water circulation unit; The hydrogen transport unit is connected to the hydrolysis hydrogenation cell and the anode chamber, and is used for transporting the released hydrogen to the anode chamber for electrochemical reaction after the solid hydrogen storage component undergoes hydrolysis hydrogenation reaction. The water circulation unit is connected to the anode chamber and the hydrolysis hydrogenation cell, and is used for extracting an aqueous solution containing un-electrolyzed hydrogen to the hydrolysis hydrogenation cell for hydrolysis hydrogenation reaction after the hydrogen in the anode chamber is electrolyzed.

[0006] Optionally, the proton exchange membrane is located on the side of the anode chamber, and a catalytic layer is provided on the side of the cathode chamber, and the proton exchange membrane allows hydrogen protons in the anode chamber to pass through and enter the cathode chamber, and the fuel cell module also includes an air intake and exhaust unit connected to the cathode chamber.

[0007] Optionally, the hydrolysis hydrogenation pool is provided with an independent hydrolysis chamber and a hydrogen storage chamber, the hydrolysis chamber is a plate-type structure, a plurality of solid hydrogen storage components are provided, and the plurality of solid hydrogen storage components are arranged side by side in the hydrolysis chamber, a gap for spraying aqueous solution is formed between two adjacent solid hydrogen storage components, and the outermost solid hydrogen storage component is attached to the inner plate surface of the hydrolysis chamber; The hydrogen storage chamber is located at the top of the hydrolysis chamber, and the hydrogen storage chamber is communicated with the hydrolysis chamber. A hydrogen inlet is provided on the anode chamber, and the hydrogen transmission unit is communicated with the anode chamber through the hydrogen inlet.

[0008] Optionally, the hydrogen transport unit includes a pressure-stabilizing buffer tank, which connects the hydrogen storage chamber and the hydrogen inlet, a one-way valve is arranged on the connecting pipeline between the hydrogen storage chamber and the pressure-stabilizing buffer tank, a safety valve and a shut-off valve are arranged in sequence on the connecting pipeline between the pressure-stabilizing buffer tank and the hydrogen inlet, and a pressure sensor is arranged on the gas outlet side of the pressure-stabilizing buffer tank.

[0009] Optionally, a hydrogen outlet is provided on the anode chamber, and the water circulation unit is connected to the anode chamber through the hydrogen outlet. The water circulation unit includes a first steam-water separator, which is connected to the hydrogen outlet, and a separation liquid outlet of the first steam-water separator is connected to the hydrolysis chamber.

[0010] Optionally, the water circulation unit further includes a first water pump and a water sprayer, and the separation liquid outlet of the first steam-water separator, the first water pump, the water sprayer and the hydrolysis chamber are connected in sequence.

[0011] Optionally, a first air inlet and a tail exhaust port are provided on the cathode chamber, the air intake and exhaust unit includes an air filter, an air compressor and an intercooler connected in sequence, the intercooler is connected to the air inlet, a second air inlet is provided on the air filter, and a flow meter is provided on the air intake side of the air compressor, and the fuel cell module also includes a tail exhaust unit connected to the tail exhaust port.

[0012] Optionally, the tail discharge unit includes a second steam-water separator, the second steam-water separator is connected to the tail discharge port, and a separation liquid outlet of the second steam-water separator is in communication with the hydrolysis hydrogenation tank.

[0013] Optionally, independent cooling chambers are respectively provided on the outer plate surfaces on both sides of the hydrolysis chamber, and the cooling chambers are respectively provided with a first medium inlet and a first medium outlet; The solid-state hydrogen pool module further includes a heat exchange unit, which includes a second water pump, a radiator, and a medium filter, wherein the first medium outlet, the second water pump, the radiator, the medium filter, and the first medium inlet are connected in sequence; A preheating chamber is disposed at the periphery of the electrolytic cell, and a second medium inlet and a second medium outlet are respectively disposed on the preheating chamber, a medium delivery pipeline is connected between the second medium inlet and the first medium outlet, and a medium circulation pipeline is connected between the second medium outlet and the first medium inlet.

[0014] The present invention also discloses a method for determining hydrogen-to-electricity conversion efficiency. Using the above-mentioned fuel cell system, the method for determining hydrogen-to-electricity conversion efficiency comprises: Obtaining a hydrogen source, and selecting a solid-state hydrogen storage material, filling the hydrogen source on the solid-state hydrogen storage material to form the solid-state hydrogen storage component, and recording the loss degree of the hydrogen source during the filling process, and obtaining the hydrogen utilization rate of the hydrogen source by calculation; The solid-state hydrogen storage component and the prepared water hydrogenation cell are modularly packaged and transported to a target location to be connected to the fuel cell module; Starting the solid-state hydrogen pool module and the fuel cell module, recording the degree of consumption of the solid-state hydrogen storage component during the water dehydrogenation reaction, and obtaining the material utilization rate of the solid-state hydrogen storage component by calculation; The hydrogen atom content of the solid hydrogen storage component in the water dehydrogenation reaction and the hydrogen atom content of the hydrogen produced after the water dehydrogenation reaction are recorded, and the hydrogen gain factor is calculated based on the recorded hydrogen atom content. The functional relationship of the hydrogen gain factor is:

[0015]

[0016] In the formula, Indicates the material category of solid-state hydrogen storage materials, Indicates that the solid hydrogen storage component contains hydrogen atoms, represents water molecules, represents the stoichiometric number of water molecules involved in the hydrolysis reaction, represents the hydroxide ion group, represents the number of hydroxide ion groups, It indicates the hydrogen produced by the reaction of water with hydrogen. represents the stoichiometric number of hydrogen produced, and n represents the hydrogen gain factor; The power generation efficiency of the fuel cell module is obtained by calculation according to the extent to which hydrogen protons in the anode chamber enter the cathode chamber for electrochemical reaction; According to the hydrogen utilization rate, the material utilization rate, the hydrogen gain factor and the power generation efficiency, the hydrogen-to-electricity conversion efficiency is obtained by calculation. The functional relationship of the hydrogen-to-electricity conversion efficiency is:

[0017] In the formula, represents the hydrogen-to-electricity conversion efficiency, represents the hydrogen utilization rate, Indicates the material utilization rate, represents the hydrogen gain factor, Indicates the efficiency of electricity generation.

[0018] Compared with the prior art, the fuel cell system based on the solid hydrogen pool and the method for determining the hydrogen-to-electricity conversion efficiency provided by the embodiments of the present invention have the following beneficial effects: By setting up an integrated solid-state hydrogen cell module and a fuel cell module, the hydrogen transport unit is used to transport the released hydrogen to the anode chamber after the solid-state hydrogen storage component undergoes hydrolysis and hydrogenation reaction, and the hydrogen protons after electrolysis in the anode chamber enter the cathode chamber through the proton exchange membrane and undergo electrochemical reaction with the air introduced into the cathode chamber, thereby generating electrical energy to achieve the hydrogen-to-electric conversion of the entire process. After the hydrogen in the anode chamber is electrolyzed by the water circulation unit, the aqueous solution containing the un-electrolyzed hydrogen is extracted to the hydrolysis and hydrogenation cell for hydrolysis and hydrogenation reaction, so that the hydrogen elements in the aqueous solution can be recycled in the hydrolysis and hydrogenation cell and the electrolysis cell for a second time, that is, the solid-state hydrogen storage component can achieve double hydrogen production effect during the hydrolysis process, so that more hydrogen atoms can be transported to the electrolysis cell to participate in the electrochemical reaction, greatly improving the energy storage and hydrogen-to-electric conversion efficiency. In addition, the solid-state hydrogen storage method is used to ensure that the hydrogen pressure of the entire system is maintained at a low level, avoiding energy consumption caused by pressure increase and pressure reduction during the transportation of hydrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, in which: Figure 1 A schematic diagram of the overall structure of a fuel cell system provided by an embodiment of the present invention; Figure 2 A schematic block diagram of the structure of the coupling between the solid-state hydrogen pool module and the fuel cell module provided in an embodiment of the present invention; Figure 3 A histogram of hydrogen pressure at different stages of hydrogen-to-electricity conversion efficiency of a fuel cell system provided by an embodiment of the present invention; Figure 4 This is a bar chart of the hydrogen pressure at different stages of hydrogen-to-electricity conversion efficiency in a traditional gas-hydrogen fuel cell system.

[0020] The symbols in the accompanying drawings are as follows: 1. Hydrolysis hydrogenation cell; 11. Hydrolysis chamber; 12. Hydrogen storage chamber; 13. Cooling chamber; 131. First medium inlet; 132. First medium outlet; 2. Solid-state hydrogen storage component; 3. Electrolytic cell; 31. Anode chamber; 311. Hydrogen inlet; 312. Hydrogen outlet; 32. Cathode chamber; 321. First air inlet; 322. Tail outlet; 4. Proton exchange membrane; 41. Catalytic layer; 5. Hydrogen transport unit; 51. Pressure stabilizing buffer tank; 52. One-way valve; 53. Safety valve; 54. Stop valve; 55. Pressure sensor; 6. Water circulation unit; 61. First steam-water separator; 62. First water pump; 63. Water sprayer; 7. Air intake and exhaust unit; 71. Air filter; 72. Air compression; 73. Intercooler; 74. Flow meter; 8. Second steam-water separator; 9. Heat exchange unit; 91. Second water pump; 92. Radiator; 93. Medium filter; 94. Medium delivery pipeline; 95. Medium circulation pipeline. DETAILED DESCRIPTION

[0021] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, a preferred embodiment of the present invention is described in detail.

[0022] The present invention discloses a fuel cell system based on a solid hydrogen pool, such as Figure 1 and Figure 2As shown, it includes an integrated assembled solid-state hydrogen cell module, a fuel cell module and a coupling module. The solid-state hydrogen cell module includes a hydrolysis hydrogen cell 1, and a solid-state hydrogen storage component 2 arranged in the hydrolysis hydrogen cell 1. The fuel cell module includes an electrolytic cell 3, and a proton exchange membrane 4 arranged in the electrolytic cell 3, and the proton exchange membrane 4 separates the electrolytic cell 3 into an anode chamber 31 and a cathode chamber 32. The coupling module includes a hydrogen transmission unit 5 and a water circulation unit 6. The hydrogen transmission unit 5 connects the hydrolysis hydrogen cell 1 and the anode chamber 31, and is used for transporting the released hydrogen to the anode chamber 31 for electrochemical reaction after the solid-state hydrogen storage component 2 undergoes hydrolysis hydrogenation reaction, and the water circulation unit 6 connects the anode chamber 31 and the hydrolysis hydrogen cell 1, and is used for extracting an aqueous solution containing un-electrolyzed hydrogen to the hydrolysis hydrogen cell 1 for hydrolysis hydrogenation reaction after the hydrogen in the anode chamber 31 is electrolyzed.

[0023] Through the implementation of the above fuel cell system embodiment, using the integrated assembled solid hydrogen cell module and fuel cell module, after the solid hydrogen storage component 2 undergoes hydrolysis and hydrogenation reaction, the released hydrogen is transported to the anode chamber 31 through the hydrogen transport unit 5, and the hydrogen protons after electrolysis in the anode chamber 31 enter the cathode chamber 32 through the proton exchange membrane 4, and react electrochemically with the air introduced into the cathode chamber 32, thereby generating electrical energy to achieve the hydrogen-to-electric conversion of the entire process. After the hydrogen in the anode chamber 31 is electrolyzed by the water circulation unit 6, the aqueous solution containing the un-electrolyzed hydrogen is extracted to the hydrolysis and hydrogenation cell 1 for hydrolysis and hydrogenation reaction, so that the hydrogen elements in the aqueous solution can be recycled in the hydrolysis and hydrogenation cell 1 and the electrolytic cell 3 through secondary recycling, that is, the solid hydrogen storage component 2 can achieve double hydrogen production effect during the hydrolysis process, so that more hydrogen atoms can be transported to the electrolytic cell 3 to participate in the electrochemical reaction, greatly improving the energy storage and hydrogen-to-electric conversion efficiency. In addition, by adopting the solid-state hydrogen storage method, the traditional high-pressure hydrogen storage method is eliminated to ensure that the hydrogen pressure of the entire system is maintained at a relatively low level. Therefore, in the transportation link of the entire solid-state hydrogen pool module, the solid-state hydrogen storage material can be pressurized by about 3MPa in the hydrogen source to realize the hydrogen-containing solid-state hydrogen storage component 2, whose hydrogen storage density is more than 20%, and can be stored at room temperature and pressure. In the transportation link, high hydrogen storage density transportation at room temperature can also be achieved, which greatly improves the efficiency of hydrogen transportation, which is more than 10 times higher than that of conventional long-tube trailer transportation, avoiding the energy consumption caused by increasing and decreasing the pressure of hydrogen during transportation.

[0024] Furthermore, the proton exchange membrane 4 is located on the side of the anode chamber 31, and the catalyst layer 41 is provided on the side of the cathode chamber 32, and the proton exchange membrane 4 allows the hydrogen protons in the anode chamber 31 to pass through and enter the cathode chamber 32. The fuel cell module also includes an air intake and exhaust unit 7 connected to the cathode chamber 32.

[0025] Through the implementation of the above fuel cell system embodiment, the proton exchange membrane 4 is located between the anode chamber 31 and the cathode chamber 32, which can effectively transfer hydrogen protons from the anode chamber 31 to the cathode chamber 32, reducing the possibility of electrons directly passing through the proton exchange membrane 4, thereby improving the energy conversion efficiency of the fuel cell module. The air intake and exhaust unit 7 is connected to the cathode chamber 32, ensuring that the cathode chamber 32 has sufficient oxygen supply, so that hydrogen protons and oxygen form an electrochemical reaction through electrochemical catalysis in the cathode chamber 32, and release electrical energy, ensuring that the fuel cell module can efficiently convert hydrogen energy into electrical energy. At the same time, the by-products discharged are mainly water vapor, which is extremely environmentally friendly, so as to meet the mass transfer conditions of the fuel cell module operation and realize stable external output power supply.

[0026] As described above, the catalyst layer 41 on both sides of the proton exchange membrane 4 is used to accelerate the oxidation reaction of hydrogen in the anode chamber 31. At the anode, hydrogen is decomposed into hydrogen atoms, and then each hydrogen atom loses an electron to form hydrogen protons, and the hydrogen protons migrate to the cathode chamber 32 through the proton exchange membrane 4. The catalyst layer 41 on this side is preferably platinum or a platinum alloy as a catalyst, which has high catalytic activity and durability. The catalyst layer 41 located in the cathode chamber 32 is used to accelerate the reduction reaction of oxygen. At the cathode, oxygen combines with the hydrogen protons that migrated through the proton exchange membrane 4 and generates water. At the same time, this process releases energy for generating electric current. The catalyst layer 41 on this side is also preferably platinum or a platinum alloy as a catalyst.

[0027] Furthermore, an independent hydrolysis chamber 11 and a hydrogen storage chamber 12 are provided in the hydrolysis hydrogenation pool 1. The hydrolysis chamber 11 is a plate-type structure, and a plurality of solid hydrogen storage components 2 are provided, and the plurality of solid hydrogen storage components 2 are arranged side by side in the hydrolysis chamber 11. A gap for spraying aqueous solution is formed between two adjacent solid hydrogen storage components 2, and the outermost solid hydrogen storage component 2 is attached to the inner plate surface of the hydrolysis chamber 11. The hydrogen storage chamber 12 is located at the top of the hydrolysis chamber 11, and the hydrogen storage chamber 12 is communicated with the hydrolysis chamber 11. A hydrogen inlet 311 is provided on the anode chamber 31, and the hydrogen transmission unit 5 is communicated with the anode chamber 31 through the hydrogen inlet 311.

[0028] Through the implementation of the above-mentioned fuel cell system embodiment, the hydrolysis chamber 11 is the place where the solid-state hydrogen storage component 2 reacts with the aqueous solution to hydrolyze hydrogen. The hydrogen released by the hydrolysis is collected in the hydrogen storage chamber 12 on the upper side, and is transported to the anode chamber 31 through the hydrogen transport unit 5 for electrochemical reaction. The solid-state hydrogen storage component 2 is preferably composed of a high hydrogen storage density hydrogen storage material injected with hydrogen. The high hydrogen storage density hydrogen storage material includes metal hydrogen storage materials and non-metallic hydrogen storage materials, mainly high hydrogen storage density hydrogen storage materials that can release hydrogen by adding water. For example, metal materials such as magnesium (Mg), calcium (Ca), aluminum (Al), hydrogen storage alloys, inorganic ionic compound hydrogen storage materials, carbonaceous hydrogen storage materials, metal organic skeleton compound hydrogen storage materials, etc. Hydrogen storage alloys include binary systems, ternary systems and multi-component systems, such as lithium hydride (LiH), sodium hydride (NaH), potassium hydride (KH), magnesium dihydride ( )、Calcium dihydride( )、Aluminum hydride( ) etc.; Inorganic ionic compound hydrogen storage materials mainly include coordinated hydrides and amino compounds, such as sodium aluminum tetrahydride ( )、lithium borohydride( ) and ammonia borane are both hydrogen storage materials with relatively high hydrogen storage density. In the solid-state hydrogen pool module, a single or multiple hydrogen storage materials with relatively high hydrogen storage density can be selected. Reversible hydrogen storage is not required, only high hydrogen storage density is required. In addition, by using multiple solid-state hydrogen storage components 2, the hydrogen storage density of the solid-state hydrogen pool module can be improved, and by using the aqueous solution formed between two adjacent solid-state hydrogen storage components 2 to spray into the gap, the contact area between the hydrogen storage material and the reaction water can be effectively increased, and the controllability of the contact area between the solid-state hydrogen storage component 2 and the reaction water can be achieved, thereby achieving the control of the hydrogen release rate and magnitude, and forming an integrated structure with high energy density for the entire solid-state hydrogen pool module.

[0029] Furthermore, the hydrogen transport unit 5 includes a pressure stabilizing buffer tank 51, which is connected to the hydrogen storage chamber 12 and the hydrogen inlet 311. A one-way valve 52 is provided on the connecting pipeline between the hydrogen storage chamber 12 and the pressure stabilizing buffer tank 51, a safety valve 53 and a stop valve 54 are provided in sequence on the connecting pipeline between the pressure stabilizing buffer tank 51 and the hydrogen inlet 311, and a pressure sensor 55 is provided on the gas outlet side of the pressure stabilizing buffer tank 51.

[0030] Through the implementation of the above-mentioned fuel cell system embodiment, the setting of the pressure stabilizing buffer tank 51 is used to make the hydrogen released by hydrolysis enter the pressure stabilizing buffer tank 51 for buffer storage, so that the hydrogen released by the solid hydrogen storage component 2 is quantitatively stored by the pressure stabilizing buffer tank 51, and a stable hydrogen storage amount can be formed in the pressure stabilizing buffer tank 51 to ensure that the application of the fuel cell module can be maintained when the solid hydrogen storage component 2 does not release hydrogen, and the pressure change impact caused by the hydrogen release reaction of the solid hydrogen storage component 2 is weakened. Combined with the pressure sensor 55, the pressure of the hydrogen supply can be monitored in real time, and the reaction rate can be adjusted at any time through the adjustment of the one-way valve 52 to ensure that the hydrogen provided to the fuel cell module can be in a relatively stable pressure range, so that the hydrogen release rate and hydrogen release pressure can be dynamically adjusted according to the demand for hydrogen by the fuel cell module. In addition, the safety valve 53 sets a certain pressure jump upper limit to protect the entire system device and ensure that the pressure can be released in time under overpressure. The stop valve 54 is used to cut off the entire set of hydrogen inlet routes.

[0031] Furthermore, a hydrogen outlet 312 is provided on the anode chamber 31, and the water circulation unit 6 is connected to the anode chamber 31 through the hydrogen outlet 312. The water circulation unit 6 includes a first steam-water separator 61, which is connected to the hydrogen outlet 312, and a separation liquid outlet of the first steam-water separator 61 is connected to the hydrolysis chamber 11.

[0032] Through the implementation of the above fuel cell system embodiment, in the electrolytic cell 3, the anode chamber 31 is where hydrogen enters, and the hydrogen protons after being electrolyzed enter the cathode chamber 32 through the proton exchange membrane 4, and generate current by electrochemical reaction with oxygen. However, during the electrolysis process in the anode chamber 31, it cannot be guaranteed that all hydrogen is completely electrolyzed, so that there will still be some electrolysis products in the anode chamber 31, mainly including unreacted hydrogen and a small amount of water vapor. Therefore, the first steam-water separator 61 is used to lead out the unreacted hydrogen and a small amount of water vapor in the anode chamber 31, and gas-water separation is performed to obtain an aqueous solution containing unreacted hydrogen and oxygen, and the aqueous solution containing unreacted hydrogen is transported to the hydrolysis hydrogenation tank 1 for hydrolysis hydrogenation reaction of the solid hydrogen storage component 2, so as to realize the recycling of hydrogen elements in the aqueous solution between the hydrolysis hydrogenation tank 1 and the electrolytic cell 3, so that the solid hydrogen storage component 2 can achieve double hydrogen production effect during the hydrolysis process.

[0033] Furthermore, the water circulation unit 6 further comprises a first water pump 62 and a water sprayer 63, and the separated liquid outlet of the first steam-water separator 61, the first water pump 62, the water sprayer 63 and the hydrolysis chamber 11 are connected in sequence.

[0034] Through the implementation of the above-mentioned fuel cell system embodiment, the first water pump 62 is responsible for pumping the separated water from the first steam-water separator 61 to the water sprayer 63, and by adjusting the opening of the water sprayer 63, the required reaction water can be sprayed into the hydrolysis chamber 11 according to the required amount of water, and sprayed on the solid hydrogen storage component 2 accordingly, so as to control the rate of the hydrogen release reaction.

[0035] Further, the cathode chamber 32 is provided with a first air inlet 321 and a tail outlet 322. The air inlet and outlet unit 7 includes an air filter 71, an air compressor 72 and an intercooler 73 connected in sequence. The intercooler 73 is connected to the air inlet, the air filter 71 is provided with a second air inlet, and a flow meter 74 is provided on the air intake side of the air compressor 72. The fuel cell module also includes a tail outlet unit connected to the tail outlet 322.

[0036] Through the implementation of the above-mentioned fuel cell system embodiment, the air filter 71 is the first line of defense of the air intake and exhaust unit 7, which is used to filter out dust, impurities and particles in the air to ensure that the air entering the subsequent components and the cathode chamber 32 remains clean. The air compressor 72 is responsible for compressing the filtered air 72 to a certain pressure to provide compressed air for the subsequent cooling process. The intercooler 73 is used to cool the compressed air and allow the cooled air to enter the cathode chamber 32 to increase the efficiency of the electrochemical reaction of the air and hydrogen protons in the cathode chamber 32 by lowering the temperature of the air. At the same time, the flow meter 74 can be used to accurately measure the air flow through the air compressor 72, which helps to better manage the power generation efficiency of the fuel cell module by understanding the air consumption. In addition, the tail exhaust unit can be used to discharge the products of the electrochemical reaction in the cathode chamber 32, such as water vapor.

[0037] Furthermore, the tail discharge unit includes a second steam-water separator 8 , which is connected to the tail discharge port 322 , and a separated liquid outlet of the second steam-water separator 8 is in communication with the hydrohydrogenation pool 1 .

[0038] Through the implementation of the above-mentioned fuel cell system embodiment, the second gas-water separator 8 is used to draw out the reaction products in the cathode chamber 32 and perform gas-water separation to obtain an aqueous solution and oxygen, and the aqueous solution is transported to the hydrohydrogenation pool 1 for the hydrohydrogenation reaction of the solid-state hydrogen storage component 2, so as to make full use of the water resources in the entire system and ensure that sufficient reaction water is introduced into the hydrohydrogenation pool 1 for the hydrohydrogenation reaction of the solid-state hydrogen storage component 2.

[0039] Furthermore, independent cooling chambers 13 are respectively provided on the outer panels on both sides of the hydrolysis chamber 11, and the cooling chambers 13 are respectively provided with a first medium inlet 131 and a first medium outlet 132. The solid-state hydrogen pool module also includes a heat exchange unit 9, and the heat exchange unit 9 includes a second water pump 91, a radiator 92 and a medium filter 93. The first medium outlet 132, the second water pump 91, the radiator 92, the medium filter 93 and the first medium inlet 131 are connected in sequence. A preheating chamber is provided on the periphery of the electrolytic cell 3, and a second medium inlet and a second medium outlet are respectively provided on the preheating chamber, and a medium delivery pipeline 94 is connected between the second medium inlet and the first medium outlet 132. A medium circulation pipeline 95 is connected between the second medium outlet and the first medium inlet 131.

[0040] Through the implementation of the above fuel cell system embodiment, the cooling chamber 13 is mainly used for cooling and circulating heat dissipation in the hydrolysis hydrogen pool 1, by filling cooling water or commercial antifreeze in the cooling chamber 13, and is independent of the hydrolysis chamber 11 and the hydrogen storage chamber 12. In order to stabilize the hydrogen release rate on the solid hydrogen storage component 2, independent cooling chambers 13 are arranged on the outer panels on both sides of the hydrolysis chamber 11, respectively, for stabilizing the balance of hydrogen release and heat release in the hydrolysis chamber 11. The second water pump 91 is a key component, which is responsible for extracting the heat exchange medium in the cooling chamber 13, and after cooling by the radiator 92, the impurities in the cooling medium are filtered out by the medium filter 93. The filtered cooling medium enters the cooling chamber 13 again, and heat is exchanged for the heat generated by the release of hydrogen in the hydrolysis chamber 11, so that the temperature of the hydrogen produced by the solid hydrogen pool module can meet the hydrogen temperature required by the fuel cell module. And by controlling the speed of the second water pump 91, the stable control of the exchange heat is achieved, thereby realizing the heat control during the hydrogen release process.

[0041] In addition, by arranging a preheating chamber on the periphery of the electrolytic cell 3 and connecting the preheating chamber with the cooling chamber 13 for heat exchange, the high-temperature medium at the outlet of the cooling chamber 13 is introduced into the cooling chamber 13, so as to perform low-temperature preheating on the inside of the electrolytic cell 3 in a winter environment, so as to ensure that the entire electrochemical reaction in the electrolytic cell 3 will not freeze at low temperatures, thereby directly converting the heat of hydrolysis of hydrogen by the solid-state hydrogen pool module to the fuel cell module for reuse at the whole machine level, so as to increase the overall energy utilization rate.

[0042] The present invention also discloses a method for determining hydrogen-to-electricity conversion efficiency. Using the above-mentioned fuel cell system, the method for determining hydrogen-to-electricity conversion efficiency includes: Obtain a hydrogen source, select a solid hydrogen storage material, add the hydrogen source to the solid hydrogen storage material to form a solid hydrogen storage component 2, and record the loss of the hydrogen source during the filling process, and obtain the hydrogen utilization rate of the hydrogen source by calculation; The solid-state hydrogen storage component 2 and the prepared water hydrogenation cell 1 are modularly packaged and transported to the target location to be connected with the fuel cell module; Start the solid-state hydrogen pool module and the fuel cell module, record the consumption degree of the solid-state hydrogen storage component 2 during the water dehydrogenation reaction, and obtain the material utilization rate of the solid-state hydrogen storage component 2 by calculation; The hydrogen atom content of the solid hydrogen storage component 2 in the water dehydrogenation reaction and the hydrogen atom content of the hydrogen produced after the water dehydrogenation reaction are recorded, and the hydrogen gain factor is calculated based on the recorded hydrogen atom content. The functional relationship of the hydrogen gain factor is:

[0043]

[0044] In the formula, Indicates the material category of solid-state hydrogen storage materials, Indicates that the solid hydrogen storage component contains hydrogen atoms, represents water molecules, represents the stoichiometric number of water molecules involved in the hydrolysis reaction, represents the hydroxide ion group, represents the number of hydroxide ion groups, It indicates the hydrogen produced by the reaction of water with hydrogen. represents the stoichiometric number of hydrogen produced, and n represents the hydrogen gain factor; The power generation efficiency of the fuel cell module is calculated based on the extent to which the hydrogen protons in the anode chamber 31 enter the cathode chamber 32 for electrochemical reaction; According to the hydrogen utilization rate, material utilization rate, hydrogen gain factor, and power generation efficiency, the hydrogen-to-electricity conversion efficiency is calculated. The functional relationship of the hydrogen-to-electricity conversion efficiency is:

[0045] In the formula, represents the hydrogen-to-electricity conversion efficiency, represents the hydrogen utilization rate, Indicates the material utilization rate, represents the hydrogen gain factor, Indicates the efficiency of electricity generation.

[0046] By implementing the above-mentioned method for determining hydrogen-to-electricity conversion efficiency, the hydrogen-to-electricity conversion calculation is performed from the flow process of the original hydrogen source, including the loss of hydrogen source during the filling process of the solid hydrogen storage material. The hydrogen source utilization rate is ; The solid hydrogen storage component 2 cannot fully participate in the reaction during the water hydrogenation process, and the material utilization rate is ; During the hydrolysis process, the hydrogen atoms contained in the reaction water also participate in the production of hydrogen, so there is a hydrogen gain factor compared to the hydrogen atoms added to the solid hydrogen storage material by the hydrogen source Here, the hydrolysis and hydrogenation reaction of the solid hydrogen storage component 2 is illustrated by examples for different solid hydrogen storage materials: When lithium is used as the solid hydrogen storage material, the solid hydrogen storage component 2 is lithium hydride (LiH), and the hydrolysis hydrogenation reaction is: ; When aluminum is used as the solid hydrogen storage material, the solid hydrogen storage component 2 is aluminum hydride ( ), the water hydrogenation reaction is: ; When magnesium is used as the solid hydrogen storage material, the solid hydrogen storage component 2 is magnesium dihydride ( ), the water hydrogenation reaction is: ; When the solid hydrogen storage material is a boron and sodium compound, the solid hydrogen storage component 2 is sodium borohydride ( ), the water hydrogenation reaction is: .

[0047] As can be seen from the reaction equation of the hydrolysis hydrogenation reaction of the solid-state hydrogen storage component 2 made of different solid-state hydrogen storage materials mentioned above, the ratio of the hydrogen atom content of the hydrogen produced after the hydrolysis hydrogenation reaction to the hydrogen atom content of the solid-state hydrogen storage component 2 (hydrogen gain factor) is 2. Therefore, the hydrogen gain factor n after various materials are mixed with each other can also be maintained at a ratio of 2.

[0048] The determination of the entire hydrogen-to-electricity conversion efficiency is to obtain hydrogen source from the hydrogen source production plant. There is a partial loss of hydrogen source in the reaction process with the solid hydrogen storage material, and there is a loss in the hydrogen storage unit during the hydrolysis and release process. Generally, the hydrogen storage material hydrolyzes to bring out hydrogen atoms in the water to achieve hydrogen gain. In terms of storage, the solid hydrogen storage component 2 uses a high hydrogen storage density material as a medium for hydrogen storage. It can store and transport hydrogen at room temperature and pressure, and it is not easy to leak. Therefore, it can be regarded as no hydrogen loss during transportation. Among them, the values ​​of hydrogen utilization rate, material utilization rate, hydrogen gain factor, power generation efficiency and hydrogen-to-electricity conversion efficiency estimation are shown in the hydrogen-to-electricity conversion table: Hydrogen-to-electricity conversion table

[0049] As shown in the hydrogen-to-electricity conversion table, the hydrogen-to-electricity conversion efficiency under this scheme is determined to be ≥80%, achieving a significant improvement in the hydrogen-to-electricity conversion efficiency. The heat dissipation efficiency of the solid-state hydrogen pool module and the fuel cell module is not included in the hydrogen-to-electricity conversion efficiency.

[0050] As mentioned above, hydrogen storage and use energy consumption. Hydrogen has the characteristics of low density and easy diffusion, and is very difficult to store and transport. Usually, in the storage and transportation of hydrogen, hydrogen needs to be pressurized and transported first, and then decompressed to low pressure for application. The compression process of hydrogen consumes a lot of energy. The method for determining the hydrogen-to-electricity conversion efficiency of the present invention cancels the high-pressure hydrogen storage method, adopts a solid-state hydrogen storage method to supply hydrogen to the fuel cell module, and realizes the terminal normal pressure hydrogen use scheme: in the entire hydrogen circulation link, obtain a normal pressure hydrogen source from the factory, and form a solid-state hydrogen storage component 2 by filling the hydrogen source under a pressure of about 3MPa on the solid-state hydrogen storage material. The hydrogen storage density of the solid-state hydrogen storage component 2 is greater than 20%, and the solid-state hydrogen storage component 2 can be stored at room temperature and pressure. In the transportation link, it also realizes normal pressure high hydrogen storage density transportation, which greatly improves the efficiency of hydrogen transportation, which is more than 10 times higher than the conventional long tube trailer transportation. In the water hydrogenation pool 1, the pressure of hydrogenation is controlled below 16bara by water hydrogenation to meet the demand for the use of hydrogen by the fuel cell module. That is, the entire method for determining the hydrogen-to-electricity conversion efficiency includes hydrogen source, material hydrogenation, solid hydrogen storage components 2, hydrogen transportation, water interpretation of hydrogen, and hydrogen use in fuel cell modules. The pressure requirement at the hydrogen end in the entire process is relatively low, <16 bara, which greatly reduces the energy consumption of hydrogen compression. Figure 3 and Figure 4 As shown, compared with the use of gaseous hydrogen, the fuel cell system of the present invention adopts solid-state hydrogen storage and hydrogen supply, and the pressure of hydrogen is maintained at a relatively low level in the entire process, thereby avoiding energy consumption caused by pressure increase and decrease of hydrogen during transportation.

[0051] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A fuel cell system based on a solid hydrogen pool, characterized in that: The fuel cell system comprises an integrated solid-state hydrogen cell module, a fuel cell module and a coupling module, wherein the solid-state hydrogen cell module comprises a water-extracted hydrogen cell and a solid-state hydrogen storage component arranged in the water-extracted hydrogen cell, the fuel cell module comprises an electrolytic cell and a proton exchange membrane arranged in the electrolytic cell, the proton exchange membrane separates the electrolytic cell into an anode chamber and a cathode chamber, and the coupling module comprises a hydrogen transport unit and a water circulation unit; The hydrogen transport unit is connected to the hydrolysis hydrogenation cell and the anode chamber, and is used for transporting the released hydrogen to the anode chamber for electrochemical reaction after the solid hydrogen storage component undergoes hydrolysis hydrogenation reaction. The water circulation unit is connected to the anode chamber and the hydrolysis hydrogenation cell, and is used for extracting an aqueous solution containing un-electrolyzed hydrogen to the hydrolysis hydrogenation cell for hydrolysis hydrogenation reaction after the hydrogen in the anode chamber is electrolyzed.

2. The fuel cell system according to claim 1, characterized in that: The proton exchange membrane is located on the side of the anode chamber, and a catalytic layer is provided on the side of the cathode chamber. The proton exchange membrane allows hydrogen protons in the anode chamber to pass through and enter the cathode chamber. The fuel cell module also includes an air intake and exhaust unit connected to the cathode chamber.

3. The fuel cell system according to claim 2, characterized in that: The hydrolysis hydrogenation pool is provided with an independent hydrolysis chamber and a hydrogen storage chamber, the hydrolysis chamber is a plate-type structure, a plurality of solid hydrogen storage components are provided, and the plurality of solid hydrogen storage components are arranged side by side in the hydrolysis chamber, a gap for spraying aqueous solution is formed between two adjacent solid hydrogen storage components, and the outermost solid hydrogen storage component is attached to the inner plate surface of the hydrolysis chamber; The hydrogen storage chamber is located at the top of the hydrolysis chamber, and the hydrogen storage chamber is communicated with the hydrolysis chamber. A hydrogen inlet is provided on the anode chamber, and the hydrogen transmission unit is communicated with the anode chamber through the hydrogen inlet.

4. The fuel cell system according to claim 3, characterized in that: The hydrogen transport unit includes a pressure-stabilizing buffer tank, which is connected to the hydrogen storage chamber and the hydrogen inlet. A one-way valve is arranged on the connecting pipeline between the hydrogen storage chamber and the pressure-stabilizing buffer tank. A safety valve and a shut-off valve are arranged in sequence on the connecting pipeline between the pressure-stabilizing buffer tank and the hydrogen inlet, and a pressure sensor is arranged on the gas outlet side of the pressure-stabilizing buffer tank.

5. The fuel cell system according to claim 3, characterized in that: The anode chamber is provided with a hydrogen outlet, the water circulation unit is communicated with the anode chamber via the hydrogen outlet, the water circulation unit comprises a first steam-water separator, the first steam-water separator is connected with the hydrogen outlet, and a separation liquid outlet of the first steam-water separator is communicated with the hydrolysis chamber.

6. The fuel cell system according to claim 5, characterized in that: The water circulation unit further comprises a first water pump and a water sprayer, and the separated liquid outlet of the first steam-water separator, the first water pump, the water sprayer and the hydrolysis chamber are connected in sequence.

7. The fuel cell system according to claim 2, characterized in that: The cathode chamber is provided with a first air inlet and a tail exhaust port, the air intake and exhaust unit includes an air filter, an air compressor and an intercooler connected in sequence, the intercooler is connected to the air inlet, the air filter is provided with a second air inlet, and a flow meter is provided on the air intake side of the air compressor, and the fuel cell module also includes a tail exhaust unit connected to the tail exhaust port.

8. The fuel cell system according to claim 7, characterized in that: The tail discharge unit comprises a second steam-water separator, the second steam-water separator is connected to the tail discharge port, and the separation liquid outlet of the second steam-water separator is communicated with the water dehydrogenation pool.

9. The fuel cell system according to claim 3, characterized in that: Independent cooling chambers are respectively arranged on the outer plate surfaces on both sides of the hydrolysis chamber, and the cooling chambers are respectively provided with a first medium inlet and a first medium outlet; The solid-state hydrogen pool module further includes a heat exchange unit, which includes a second water pump, a radiator, and a medium filter, wherein the first medium outlet, the second water pump, the radiator, the medium filter, and the first medium inlet are connected in sequence; A preheating chamber is disposed at the periphery of the electrolytic cell, and a second medium inlet and a second medium outlet are respectively disposed on the preheating chamber, a medium delivery pipeline is connected between the second medium inlet and the first medium outlet, and a medium circulation pipeline is connected between the second medium outlet and the first medium inlet.

10. A method for determining hydrogen-to-electricity conversion efficiency, characterized in that: Using the fuel cell system according to any one of claims 1 to 9, the method for determining the hydrogen-to-electricity conversion efficiency comprises: Obtaining a hydrogen source, and selecting a solid-state hydrogen storage material, filling the hydrogen source on the solid-state hydrogen storage material to form the solid-state hydrogen storage component, and recording the loss degree of the hydrogen source during the filling process, and obtaining the hydrogen utilization rate of the hydrogen source by calculation; The solid-state hydrogen storage component and the prepared water dehydrogenation cell are modularly packaged and transported to a target location to be connected to the fuel cell module; Starting the solid-state hydrogen pool module and the fuel cell module, recording the degree of consumption of the solid-state hydrogen storage component during the water dehydrogenation reaction, and obtaining the material utilization rate of the solid-state hydrogen storage component by calculation; The hydrogen atom content of the solid hydrogen storage component in the water dehydrogenation reaction and the hydrogen atom content of the hydrogen produced after the water dehydrogenation reaction are recorded, and the hydrogen gain factor is calculated based on the recorded hydrogen atom content. The functional relationship of the hydrogen gain factor is: In the formula, Indicates the material category of solid-state hydrogen storage materials, Indicates that the solid hydrogen storage component contains hydrogen atoms, represents water molecules, represents the stoichiometric number of water molecules involved in the hydrolysis reaction, represents the hydroxide ion group, represents the number of hydroxide ion groups, It indicates the hydrogen produced by the reaction of water with hydrogen. represents the stoichiometric number of hydrogen produced, and n represents the hydrogen gain factor; The power generation efficiency of the fuel cell module is obtained by calculation according to the extent to which hydrogen protons in the anode chamber enter the cathode chamber for electrochemical reaction; According to the hydrogen utilization rate, the material utilization rate, the hydrogen gain factor and the power generation efficiency, the hydrogen-to-electricity conversion efficiency is obtained by calculation. The functional relationship of the hydrogen-to-electricity conversion efficiency is: In the formula, represents the hydrogen-to-electricity conversion efficiency, represents the hydrogen utilization rate, Indicates the material utilization rate, represents the hydrogen gain factor, Indicates the efficiency of electricity generation.

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