Introduction to fuel cell

Fuel cell is a chemical device that converts the chemical energy of fuel directly into electrical energy. It is also known as electrochemical generator, which is the fourth power generation technology after hydropower, thermal power generation and atomic power generation. Because the fuel cell converts the Gibbs free energy part of the chemical energy of the fuel into electrical energy through electrochemical reaction. It is not limited by the Carnot cycle effect, so the efficiency is high. In addition, the fuel cell uses fuel and oxygen as raw materials. And there is no mechanical transmission component. So the emission of harmful gases is very little and the service life is long. Thus, from the perspective of saving energy and protecting the ecological environment, fuel cells are the most promising power generation technology

Fuel cell type

Hydrogen fuel cell

Hydrogen fuel cells are power generation devices that directly convert the chemical energy of hydrogen and oxygen into electrical energy. The basic principle is the reverse reaction of electrolyzing water, which supplies hydrogen and oxygen to the anode and cathode respectively. Hydrogen diffuses outward through the anode and reacts with the electrolyte, releasing electrons to reach the cathode through an external load.

DMFC

Proton exchange membrane fuel cells that directly use methanol as fuel are often called direct methanol fuel cells (DMFC). The membrane electrode is mainly composed of methanol anode, oxygen cathode and proton exchange membrane (PEM). The anode and cathode are respectively composed of stainless steel plate, plastic film, copper current collecting plate, graphite, gas diffusion layer and catalytic layer with porous structure. The gas diffusion layer supports the catalytic layer, collects current and conducts reactants. And is composed of carbon paper or carbon cloth with conductive function. The catalytic layer is the site of electrochemical reaction. And the commonly used anode and cathode electrode catalysts are PtRu/C and Pt/C respectively.
Direct methanol fuel cell does not need intermediate conversion device. So the system structure is simple, high volume energy density. But also has the advantages of short starting time, good load response characteristics, high operational reliability. It can work normally in a large temperature range, convenient fuel supplement and so on. The application field is very wide, mainly divided into: (1) portable mobile power supply in field operation or military field. (2) 50 ~ 1 000kW fixed power generation equipment; (3) Future electric vehicle power source; (4) Power supply for mobile communication equipment.