CN-122025711-A - Fuel cell system

Abstract

The invention belongs to the technical field of electrochemistry, and discloses a fuel cell system which comprises a formaldehyde fuel cell unit and a hydrogen fuel cell unit, wherein hydrogen generated by the formaldehyde fuel cell unit is conveyed to the hydrogen fuel cell unit, the formaldehyde fuel cell unit comprises a cathode chamber and an anode chamber which are separated by a proton exchange membrane, a catholyte in the cathode chamber is sulfuric acid solution, an anolyte in the anode chamber is aqueous solution containing potassium hydroxide and formaldehyde, a cathode electrode in the cathode chamber is an electrode capable of catalyzing hydrogen evolution reaction, and an anode electrode in the anode chamber is an electrode capable of catalyzing formaldehyde to oxidize to generate hydrogen. The hydrogen generated by the formaldehyde fuel cell unit is conveyed to the hydrogen fuel cell unit through a pipeline, so that low-cost in-situ hydrogen production, hydrogen supply and power supply are realized. The anode electrode material for catalyzing formaldehyde oxidation hydrogen evolution specifically is adopted, so that the hydrogen production efficiency of formaldehyde oxidation is improved. By the concentration setting of the electrolyte in the cathode chamber and the anode chamber and the selection of the anode electrode, a higher open circuit voltage is achieved.

Inventors

• SHE GUANGWEI
• HAO XUE
• YU YU
• WANG HAOJING
• SHI WENSHENG

Assignees

• 中国科学院理化技术研究所

Dates

Publication Date

20260512

Application Date

20251226

Claims (10)

1. 1. A fuel cell system, characterized by comprising: the formaldehyde fuel cell unit and the hydrogen fuel cell unit are connected with each other in a way that hydrogen generated by the formaldehyde fuel cell unit is conveyed to the hydrogen fuel cell unit; the formaldehyde fuel cell unit comprises a cathode chamber and an anode chamber which are separated by a proton exchange membrane; the cathode electrolyte in the cathode chamber is sulfuric acid solution; the anode electrolyte in the anode chamber is an aqueous solution containing potassium hydroxide and formaldehyde; The cathode chamber also comprises a cathode electrode; the anode chamber also includes an anode electrode.
2. 2. The fuel cell system according to claim 1, wherein, The anode electrode is an electrode based on at least one of copper, gold and silver; Or alternatively, the first and second heat exchangers may be, The anode electrode is any one of copper foam loaded with a Cu catalyst, copper foam loaded with an Ag catalyst, copper foam loaded with an Au catalyst and copper foam loaded with a CuMo catalyst.
3. 3. The fuel cell system according to claim 1, wherein, The anode electrode is formed by supporting a copper-based catalyst by a conductive substrate, the copper-based electrocatalyst is an alloy consisting of nickel and copper, the nickel atom accounts for 6% of the molar ratio, the copper atom accounts for 94% of the molar ratio, and the copper-based electrocatalyst is a Cu 0.94 Ni 0.06 electrocatalyst.
4. 4. The fuel cell system according to claim 3, wherein, The anode electrode is composed of a copper foam supported Cu 0.94 Ni 0.06 electrocatalyst.
5. 5. The fuel cell system according to claim 3, wherein, The Cu 0.94 Ni 0.06 electrocatalyst has a dendritic morphology with a length of 6-8 microns.
6. 6. The fuel cell system according to claim 1, wherein, The concentration of sulfuric acid in the catholyte is 0.5 mol/L-2.5 mol/L; the concentration of potassium hydroxide in the anolyte is 1 mol/L-5 mol/L; wherein the concentration ratio of the sulfuric acid to the potassium hydroxide is 1:2.
7. 7. The fuel cell system according to claim 1, wherein, The concentration of sulfuric acid in the catholyte is 0.5mol/L; the concentration of potassium hydroxide in the anolyte is 1mol/L; the concentration of formaldehyde in the anolyte is 0.6mol/L.
8. 8. The fuel cell system according to claim 1, wherein, The concentration of formaldehyde in the anolyte is 0.6 mol/L-1.4 mol/L.
9. 9. The fuel cell system according to claim 1, wherein, The cathode electrode is any one of a platinum carbon electrode, a Pt electrode, a Re electrode, a Rh electrode, a Pd electrode and a Ru electrode.
10. 10. The fuel cell system according to any one of claims 1 to 9, wherein, And stirring devices are arranged in the anode chamber and the cathode chamber, and the stirring speed is 100-600 rpm.

Description

Fuel cell system Technical Field The invention belongs to the technical field of electrochemistry. More particularly, the present invention relates to a fuel cell system. Background A fuel cell is a device that directly converts chemical energy of fuel and oxidant into electric energy through an electrochemical reaction. Unlike traditional internal combustion engine or combustion power generation technology, the fuel cell does not depend on combustion process, has the advantages of high energy conversion efficiency, low emission, low noise and the like, has wide application prospect in the fields of new energy automobiles, distributed power generation, aerospace and the like, and is considered as an important development direction of clean energy technology in the future. Conventional structures of fuel cells include an anode, a cathode, an electrolyte, and an external circuit. The fuel of the anode is oxidized to release electrons, the electrons are transmitted to the cathode through an external circuit, the oxidant of the cathode is reduced to receive the electrons, and protons or ions are transmitted between the anode and the cathode through the electrolyte to form a circuit loop. Fuel cells have different characteristics due to the use of different electrolytes, fuels, oxidants, and electrocatalysts. Fuel cells have been developed from the original pure hydrogen to ammonia, hydrazine, ethylene glycol, methanol, and natural gas in various forms. For example, hydrogen fuel cells produce electrical energy and water using hydrogen as a fuel, oxygen as an oxidant, and aqueous potassium hydroxide as an electrolyte. The direct methanol fuel cell uses aqueous methanol as fuel. The fuel cell for producing hydrogen by reforming methanol takes hydrogen obtained by reforming methanol as fuel. Natural gas fuel cells use hydrocarbons such as methane as fuel. Hydrogen fuel cells are one of the most commercially viable technical routes due to their high power density, rapid start-up, and non-pollution of combustion products. The hydrogen source of the hydrogen fuel cell forms a restriction on the popularization and application thereof. For example, relying on fossil fuel reforming to produce hydrogen or electrolysis of water to produce hydrogen can result in emissions pollution or high costs. By utilizing green electricity such as wind power, photovoltaic and the like to decompose water, zero carbon emission but high energy consumption is realized, and the hydrogen production efficiency by electrolysis still has room for improvement. The nuclear energy hydrogen production can continuously and stably provide a large amount of clean energy without being influenced by factors such as weather, but the problems of nuclear energy safety, nuclear waste disposal and the like still remain the main challenges facing the development of the problems. In addition, the storage and transportation of hydrogen are also problematic, the weight density and the volume density of the hydrogen storage technology need to be further improved due to high-pressure compression or low-temperature liquefaction storage of hydrogen, the existing storage and transportation mode consumes higher cost, and potential safety hazards such as high-pressure leakage and hydrogen embrittlement exist. Compared with other raw materials, formaldehyde is used as a hydrogen carrier and has the characteristics of safe transportation, high hydrogen content and easy conversion, and in recent years, the hydrogen production from formaldehyde is paid attention to the scientific community. However, the hydrogen production from formaldehyde has higher requirements on the specificity of the catalyst, and no efficient catalyst for improving the hydrogen production rate of formaldehyde oxidation is available at present, so that the hydrogen production path is obstructed. In view of the foregoing, there is a need for an efficient, safe, low cost in situ hydrogen production and supply scheme to enhance the practicality and economy of hydrogen fuel cells. Disclosure of Invention In order to solve at least one or more of the technical problems mentioned above, the present invention provides a fuel cell system including a formaldehyde fuel cell unit and a hydrogen fuel cell unit, hydrogen generated by the formaldehyde fuel cell unit being supplied to the hydrogen fuel cell unit as fuel thereof, the hydrogen fuel cell unit converting hydrogen energy into electric energy. Hydrogen fuel cells can be used as commercially available hydrogen fuel cells of well-established technology, formaldehyde fuel cells comprising a cathode compartment and an anode compartment separated by a proton exchange membrane. The electrolyte of the anode chamber is alkaline aqueous solution containing formaldehyde, the electrolyte of the cathode chamber is acidic aqueous solution, and the output voltage of the battery can be regulated by regulating the concentration of the electrolyte in the cathode chamber