Molten salt fuel cell

Abstract

The utility model relates to a fused salt fuel cell which comprises a cell device, fused salt electrolyte, positive fuel and negative fuel, the negative fuel comprises carbon, the positive fuel comprises oxygen-containing gas, the cell device comprises a reaction tank and a feeding device located above the reaction tank, a containing cavity is formed in the reaction tank and used for containing the fused salt electrolyte, and the oxygen-containing gas is contained in the containing cavity. The feeding device comprises a flow guide pipe, and a positive electrode fuel feeding part and a negative electrode fuel feeding part which are respectively connected with the flow guide pipe, and the flow guide pipe extends into the accommodating cavity of the reaction tank. The gas product of the molten salt fuel cell is single and is CO2, the CO2 can be conveniently collected through the gas outlet pipe in the flow guide pipe of the device, the collected CO2 is very pure, later-stage utilization of the CO2 or direct treatment of the CO2 is facilitated, and the emission reduction cost of carbon dioxide treatment is reduced. The reaction of the positive electrode fuel does not need a catalyst, so that the electrolyte and the electrode cannot be corroded.

Description

Technical Field

[0001] The utility model relates to a molten salt fuel cell, belonging to the technical field of fuel cells. Background Art

[0002] Currently, fuel cells used for civilian power generation usually use molten carbonate fuel cells. The molten carbonate fuel cell uses carbonate in a molten state at high temperature as the electrolyte and liquefied natural gas as the fuel. The power generation efficiency can reach 50% - 55%, the working temperature is 600 - 700°C, and it can reach 55% - 60% when combined with steam power generation. It can not only directly utilize waste heat for heating, but also the discharged high-temperature gas can be used to drive a steam turbine for secondary power generation.

[0003] However, the molten carbonate fuel cell uses hydrogen or reformed gas to react at the anode under the catalysis of a catalyst such as nickel, and uses a ceramic diaphragm made by soaking molten carbonate with lithium metaaluminate powder as the electrolyte. This electrolyte must well isolate the reaction gases at the cathode and anode, otherwise it is very easy to explode. Sulfur cannot exist in the anode reactor, otherwise it is easy to corrode the electrolyte and electrodes.

[0004] Therefore, there is an urgent need to develop a battery whose anode does not require a catalyst, can solve the problems of electrode and electrolyte corrosion, and at the same time solve the problem that the electrolyte has high gas isolation requirements, otherwise it is easy to explode. Summary of the Utility Model

[0005] In order to solve the problems of electrode and electrolyte corrosion caused by the need for a catalyst in the anode of the existing battery, and at the same time solve the defect of the battery with high gas isolation requirements for the electrolyte, otherwise it is easy to explode, this application provides a molten salt fuel cell, which includes a battery device, a molten salt electrolyte, a positive electrode fuel, and a negative electrode fuel. The negative electrode fuel includes carbon, the positive electrode fuel includes an oxygen-containing gas, the battery device includes a reaction tank and a feeding device located above the reaction tank. The reaction tank has an accommodation cavity therein for containing the molten salt electrolyte. The feeding device includes a diversion pipe, a positive electrode fuel feeding part and a negative electrode fuel feeding part respectively connected to the diversion pipe. The diversion pipe extends into the accommodation cavity of the reaction tank, and the diversion pipe is used to guide the negative electrode fuel and the positive electrode fuel to enter the electrolyte for reaction.

[0006] Further, a liquid inlet pipe is connected to one side wall of the reaction tank, and a liquid outlet pipe is on the other side.

[0007] Further, the molten salt electrolyte includes a mixed solution of one or more of Na3AlF6 molten salt, K3AlF6 molten salt, and Li3AlF6 molten salt.

[0008] Further, an air outlet pipe is sleeved inside the diversion pipe, and the air outlet pipe is fixed inside the diversion pipe.

[0009] Further, the operating temperature of the molten salt electrolyte is between 800 and 900 °C.

[0010] Further, the oxygen concentration in the oxygen-containing gas is 21%-70%.

[0011] Further, the negative electrode fuel carbon includes solid carbon, and the solid carbon includes at least one of activated carbon or carbon black.

[0012] Further, the negative electrode fuel carbon further includes a carbon-containing gas, and the carbon-containing gas includes any one or a mixture of multiple of acetylene, ethylene, methane, ethanol, methanol, and isopropanol.

[0013] In summary, the present application has the following beneficial effects:

[0014] First, in the present application, fuel carbon is used as the negative electrode material of the battery material. Electrical energy is converted from electrons in the negative electrode viewing area by the fuel carbon, and the product is a carbon oxide. Moreover, through the coupling and recycling of the carbon oxide, the fuel carbon and the oxygen-containing gas are consumed, thereby realizing continuous power generation. The implementation method of the overall molten salt fuel cell is simple and has a high energy conversion rate;

[0015] Second, compared with traditional electrolyte materials, the cryolite molten salt selected in the present application has a lower melting point and can be melted at 800-900 °C. This enables cryolite to effectively reduce the temperature of the electrolyte and reduce energy consumption. Secondly, the cryolite molten salt used in the present application as the electrolyte has good electrical conductivity, which is conducive to the transfer of current and the progress of the electrolysis process. At the same time, the cryolite molten salt is not easily decomposed during the electrolysis process, thus ensuring the stability of the electrolysis process and the purity of the product, meeting the requirements for it to be used as the electrolyte material of the molten salt fuel cell;

[0016] Third, the gas product of the molten salt fuel cell in the present application is single, which is CO2. CO2 can be conveniently collected through the gas outlet pipe in the diversion pipe of this device, and the collected CO2 is very pure, which is also convenient for the subsequent utilization of CO2 or the direct treatment of CO2, reducing the emission reduction cost of treating carbon dioxide;

[0017] Fourth, the molten salt fuel cell of the present utility model has a high electro-conversion efficiency, and its reaction entropy change is less than 3 J / kmol;

[0018] Fifth, the positive electrode fuel and the negative electrode fuel of the molten salt fuel cell of the present utility model are rich in reserves and widely distributed on the earth. Their resource prices are cheap, and only a small amount and cheap fuel are needed to obtain the same electric power resources, with high economic benefits;

[0019] Sixth, the reaction of the positive electrode fuel does not require a catalyst and will not corrode the electrolyte and the electrode. Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of the molten salt fuel cell device of the present utility model;

[0021] Wherein: 1. Battery device; 2. Reaction tank; 3. Feeding device; 31. Diversion pipe; 32. Positive electrode fuel feeding part; 33. Negative electrode fuel feeding part; 34. Air outlet pipe. Detailed Embodiments

[0022] In order to further understand the present utility model, the preferred implementation schemes of the present utility model will be described below in conjunction with embodiments. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present utility model, rather than limiting the claims of the utility model.

[0023] For all raw materials of the present utility model, there is no particular limitation on their sources, and they can be purchased on the market or prepared by conventional methods well-known to those skilled in the art.

[0024] For all raw materials of the present utility model, there is no particular limitation on their purity. The present utility model preferably adopts analytical pure or the conventional purity requirements in the field of polypropylene material preparation.

[0025] For all raw materials of the present utility model, their trade names and abbreviations are all conventional trade names and abbreviations in the field. Each trade name and abbreviation is clear and definite in the field of its related uses. Those skilled in the art can purchase or prepare them by conventional methods according to the trade name, abbreviation and corresponding uses.

[0026] Such as Figure 1 The molten salt fuel cell described above includes a battery device 1, a molten salt electrolyte, a positive electrode fuel and a negative electrode fuel. The molten salt electrolyte includes a mixed solution of one or more of Na3AlF6 molten salt, K3AlF6 molten salt and Li3AlF6 molten salt. The molten salt electrolyte is a cryolite molten salt electrolyte at 800 - 900 °C. The negative electrode fuel is carbon powder, and the positive electrode fuel is an oxygen-containing gas. The oxygen concentration in the oxygen-containing gas is 21% - 70%. In this embodiment, the negative electrode fuel is carbon powder. In other embodiments, the negative electrode fuel can be not only solid carbon but also carbon-containing gas. The carbon-containing gas includes any one or a mixture of acetylene, ethylene, methane, ethanol, methanol, isopropanol. The fuel carbon includes solid carbon, and the solid carbon includes at least one of activated carbon or carbon black.

[0027] The battery device 1 includes a reaction tank 2 and a feeding device 3. The reaction tank 2 is located below the feeding device 3. The reaction tank 2 has an accommodation cavity therein for accommodating a molten salt electrolyte. A liquid inlet pipe is connected to one side wall of the reaction tank 2, and a liquid outlet pipe is on the other side, which is convenient for replacing the molten salt electrolyte and also convenient for cleaning the reaction tank 2. The feeding device 3 includes a positive electrode fuel feeding part 32, a negative electrode fuel feeding part 33, and a diversion pipe 31. The positive electrode fuel feeding part 32 and the negative electrode fuel feeding part 33 are respectively connected to the diversion pipe 31 for guiding the negative electrode fuel and the positive electrode fuel to enter the molten salt electrolyte for reaction. The diversion pipe 31 extends into the accommodation cavity of the reaction tank 2.

[0028] An air outlet pipe 34 is sleeved inside the diversion pipe 31, and the air outlet pipe 34 is fixed inside the diversion pipe 31.

[0029] When using the battery device 1, first open the valve, add the molten salt electrolyte into the reaction tank 2 until the molten salt electrolyte reaches the preset liquid level, and make the pipe of the feeding device 3 extend into the molten salt electrolyte; then continuously feed the positive electrode fuel oxygen-containing gas into the positive electrode fuel feeding part 32 and continuously feed the negative electrode fuel carbon into the negative electrode fuel feeding part 33.

[0030] The positive electrode fuel and the negative electrode fuel fall into the molten salt electrolyte. The O2 molecules contained in the positive electrode fuel are adsorbed onto the negative electrode material fuel carbon, gain electrons to generate oxygen ions, and the oxygen ions are then transferred to the positive electrode by the molten salt electrolyte to undergo an electrochemical oxidation reaction with CO to generate CO2 and electrons. The reaction formula is as follows:

[0031] O 2- +CO = CO2 + 2e - Formula (1)

[0032] The generated CO2 diffuses to the surface of the fuel carbon to undergo a carbon dissolution loss reaction, generating more CO. The reaction formula is as follows:

[0033] C + CO2 = 2CO Formula (2)

[0034] Among them, the generated CO repeatedly diffuses to the positive electrode of the molten salt fuel cell and undergoes the electrochemical oxidation reaction as shown in Formula (1) again. Through the coupling and circulation of Formula (1) and Formula (2), the fuel carbon and the oxygen-containing gas are consumed, thereby generating electric energy and realizing the continuous generation of electric energy by the molten salt fuel cell. CO2 is discharged upward from the air outlet pipe of this device, which is convenient to collect CO2, and the collected CO2 is very pure, which is also convenient for the subsequent utilization of CO2 or the direct treatment of CO2, reducing the emission reduction cost of treating carbon dioxide.

[0035] This specific embodiment is only an interpretation of the present application and does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A molten salt fuel cell, characterized in that: The invention comprises a battery device (1), a molten salt electrolyte, a positive electrode fuel and a negative electrode fuel, wherein the negative electrode fuel comprises carbon and the positive electrode fuel comprises an oxygen-containing gas. The battery device (1) comprises a reaction tank (2) and a feeding device (3) located above the reaction tank (2); the reaction tank (2) has a containing cavity therein for containing a molten salt electrolyte. The feeding device (3) comprises a flow guide tube (31), a positive electrode fuel feeding part (32) and a negative electrode fuel feeding part (33) respectively connected to the flow guide tube (31); the flow guide tube (31) extends into the accommodating cavity of the reaction tank (2); the flow guide tube (31) is used to guide the negative electrode fuel and the positive electrode fuel to enter the electrolyte for reaction.

2. The molten salt fuel cell according to claim 1, characterized in that: One side wall of the reaction tank (2) is connected to a liquid inlet pipe, and the other side is provided with a liquid outlet pipe.

3. The molten salt fuel cell according to claim 1, characterized in that: The molten salt electrolyte includes a mixed solution of one or more of Na3AlF6 molten salt, K3AlF6 molten salt and Li3AlF6 molten salt.

4. The molten salt fuel cell according to claim 1, characterized in that: An air outlet pipe (34) is sleeved inside the flow guide pipe (31), and the air outlet pipe (34) is fixed inside the flow guide pipe (31).

5. The molten salt fuel cell according to claim 3, characterized in that: The operating temperature of the molten salt electrolyte is between 800-900°C.

6. The molten salt fuel cell according to claim 1, characterized in that: The oxygen concentration in the oxygen-containing gas is 21%-70%.

7. The molten salt fuel cell according to claim 1, characterized in that: The negative electrode fuel carbon includes solid carbon, and the solid carbon includes at least one of activated carbon or carbon black.

8. The molten salt fuel cell according to claim 1, characterized in that: The negative electrode fuel carbon also includes carbon-containing gas, and the carbon-containing gas includes a mixture of any one or more of acetylene, ethylene, methane, ethanol, methanol, and isopropanol.

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