What are the current mainstream directions of fuel cell research? Do carbonate fuel cells have a future? -Lithium - Ion Battery Equipment
Fuel power cells directly convert chemical energy (fuel) into electrical energy. They have the advantages of high efficiency and low pollution. In recent years, they have received great attention from all aspects. Molten carbonate fuel cells (MCFC) operate at high temperatures (about 650C) and can use exhaust waste heat and gas turbines to generate electricity. Therefore, they have higher efficiency and are one of the mainstreams of current fuel cell research.
Many achievements have been made in MCFC fuel power cell research in the past, including Proect's 2.85MW MCFC demonstration project, the 15kW MCFC successfully researched by Shanghai Jiao Tong University, and the 100kW MCFC currently being studied. Despite this, as a new generation of energy system, there are many aspects of the working mechanism of fuel power cells, whether it is the electrochemical reaction process, the heat mass transfer process, the flow process of oxidant and fuel inside the battery, or the steady state of the fuel power cell. and dynamic characteristics need to be further studied. Only on the basis of mastering the rules can these processes be organized well, so that fuel power cells can truly become an efficient and clean energy system.(Lithium - Ion Battery Equipment)
The focus of this article is to study the dynamic characteristics of MCFC batteries. The exploration of dynamic characteristics is not only necessary to reveal the temperature distribution, flow state, and performance change rules of the fuel power cell itself, but also provides essential basic data for the hybrid system formed by combining the fuel power cell and the gas turbine. Many physical parameters of the MCFC model studied in this article were obtained from the 15kW molten carbonate fuel power cell of the Fuel Power Cell Research Institute of Shanghai Jiao Tong University.
Internal characteristics of MCFC Monomeric molten carbonate fuel power cells are generally flat-plate type, consisting of electrodes-electrolytes, fuel flow channels, oxidant flow channels and upper and lower separators, see.
The working process of the fuel power cell is: H2 in the fuel flow undergoes an oxidation reaction in the anode, and uses C3- ions in the electrolyte to generate H2O and C2, releasing electrons: +2e, O2 in the oxidant flow in the cathode (Cathode) And CO2 uses and captures electrons to generate CO3- into the electrolyte: (1/2) O2+CO2+2eCO3-, then CO32- diffuses freely to the Anode of the fuel flow, replenishing the consumed CO3' Anode's germinating electrons pass through the external circuit junction ICathode, thus forming a complete loop including electron transport and ion movement. The intensity of the electrochemical reaction can be expressed by the number of moles of substances participating in the electrochemical reaction per unit area on the electrode plate-electrolyte per unit time, that is, the electrochemical reaction rate. It can be seen that the electrochemical reaction process is accompanied by a strong mass transfer process. The above The working process has explained the flow direction of O2, CO2, CO3-, and H2O. For every 2g of substances (Ma) consumed in the fuel flow, 60g (1/2O2 and CO2) of substances enter the electrode from the oxidant side to form CO3-, pass through the electrolyte, and enter the fuel flow to become CO2 and H2O. This strong transmission The impact of mass processes on the internal thermodynamic properties of fuel power cells is significant. The mass transfer intensity can be expressed by the mass transfer rate. The combination of heat generation and transfer processes in the fuel power cell can be decomposed as follows. The heat generated inside the battery includes the heat generated by the electrochemical reaction and the resistance heat generated by the current. The heat of electrochemical reaction is mainly the heat of formation of water, and the heat of electrochemical reaction per unit area is /mol; DS is the entropy change of generated water, /(mol.K); 7; is the uniform temperature of the electrode plate-electrolyte, K. Unit The resistance heat generated by the area current is not only the electrochemical reaction heat and resistance heat, but also the heat brought into and taken out of the fuel power cell by the fuel flow and oxidant flow. The next section will establish heat and mass balance equations to form a mathematical model of the dynamic process of the fuel power cell.
Single MCFC micro-element mass transfer and heat transfer schematic diagram of MCFC dynamic process mathematical model 3.1 Overview The ways of heat energy transfer inside the fuel power cell are: heat transfer caused by mass transfer fuel and oxidant flow counter electrode-electrolyte and separator interaction Convection heat transfer electrode-radiation heat transfer between electrolyte and separator, etc.
Many achievements have been made in MCFC fuel power cell research in the past, including Proect's 2.85MW MCFC demonstration project, the 15kW MCFC successfully researched by Shanghai Jiao Tong University, and the 100kW MCFC currently being studied. Despite this, as a new generation of energy system, there are many aspects of the working mechanism of fuel power cells, whether it is the electrochemical reaction process, the heat mass transfer process, the flow process of oxidant and fuel inside the battery, or the steady state of the fuel power cell. and dynamic characteristics need to be further studied. Only on the basis of mastering the rules can these processes be organized well, so that fuel power cells can truly become an efficient and clean energy system.(Lithium - Ion Battery Equipment)
The focus of this article is to study the dynamic characteristics of MCFC batteries. The exploration of dynamic characteristics is not only necessary to reveal the temperature distribution, flow state, and performance change rules of the fuel power cell itself, but also provides essential basic data for the hybrid system formed by combining the fuel power cell and the gas turbine. Many physical parameters of the MCFC model studied in this article were obtained from the 15kW molten carbonate fuel power cell of the Fuel Power Cell Research Institute of Shanghai Jiao Tong University.
Internal characteristics of MCFC Monomeric molten carbonate fuel power cells are generally flat-plate type, consisting of electrodes-electrolytes, fuel flow channels, oxidant flow channels and upper and lower separators, see.
The working process of the fuel power cell is: H2 in the fuel flow undergoes an oxidation reaction in the anode, and uses C3- ions in the electrolyte to generate H2O and C2, releasing electrons: +2e, O2 in the oxidant flow in the cathode (Cathode) And CO2 uses and captures electrons to generate CO3- into the electrolyte: (1/2) O2+CO2+2eCO3-, then CO32- diffuses freely to the Anode of the fuel flow, replenishing the consumed CO3' Anode's germinating electrons pass through the external circuit junction ICathode, thus forming a complete loop including electron transport and ion movement. The intensity of the electrochemical reaction can be expressed by the number of moles of substances participating in the electrochemical reaction per unit area on the electrode plate-electrolyte per unit time, that is, the electrochemical reaction rate. It can be seen that the electrochemical reaction process is accompanied by a strong mass transfer process. The above The working process has explained the flow direction of O2, CO2, CO3-, and H2O. For every 2g of substances (Ma) consumed in the fuel flow, 60g (1/2O2 and CO2) of substances enter the electrode from the oxidant side to form CO3-, pass through the electrolyte, and enter the fuel flow to become CO2 and H2O. This strong transmission The impact of mass processes on the internal thermodynamic properties of fuel power cells is significant. The mass transfer intensity can be expressed by the mass transfer rate. The combination of heat generation and transfer processes in the fuel power cell can be decomposed as follows. The heat generated inside the battery includes the heat generated by the electrochemical reaction and the resistance heat generated by the current. The heat of electrochemical reaction is mainly the heat of formation of water, and the heat of electrochemical reaction per unit area is /mol; DS is the entropy change of generated water, /(mol.K); 7; is the uniform temperature of the electrode plate-electrolyte, K. Unit The resistance heat generated by the area current is not only the electrochemical reaction heat and resistance heat, but also the heat brought into and taken out of the fuel power cell by the fuel flow and oxidant flow. The next section will establish heat and mass balance equations to form a mathematical model of the dynamic process of the fuel power cell.
Single MCFC micro-element mass transfer and heat transfer schematic diagram of MCFC dynamic process mathematical model 3.1 Overview The ways of heat energy transfer inside the fuel power cell are: heat transfer caused by mass transfer fuel and oxidant flow counter electrode-electrolyte and separator interaction Convection heat transfer electrode-radiation heat transfer between electrolyte and separator, etc.
