Principle of hydrogen fuel cell new energy vehicle

Unlike rockets, hydrogen fuel cells generate kinetic energy through the violent reaction of hydrogen and oxygen combustion, but release Gibbs free energy in hydrogen through catalytic devices. For example, graphite and diamond are both carbon. But forming diamond requires high temperature and high pressure. Therefore, this form transformation represents different Gibbs free energy.

Gibbs free energy is an electrochemical energy involving entropy and enthalpy. Do you think it is very profound and difficult to understand? Let's watch the animation directly.

↑ Working principle of hydrogen fuel cell

The working principle of hydrogen fuel cell is that hydrogen is decomposed into electrons and hydrogen ions (protons) through the catalyst (platinum) in the positive pole of the fuel cell. The protons reach the negative electrode through the Proton Exchange Membrane and react with oxygen to become water and heat. The corresponding electrons flow from the positive pole to the negative pole through the external circuit to generate electric energy.

Speaking of hydrogen fuel cell vehicles, proton exchange membrane fuel cell (PEMFC) technology is currently the mainstream. The system is usually composed of fuel cell stack, hydrogen storage tank, power cell, fuel cell DC boost converter, power control unit and power motor. At present, the power density of the leading fuel cell stack can reach 3.1kW/L, and the maximum output power can reach 114kW. Since the output voltage of each fuel cell is only 0.6~0.7V, it needs to be used with DC boost converter and power battery. So that the voltage can adapt to 650V high voltage to drive the power motor. At the same time, similar to the power battery, the battery management system BMS is needed, and the fuel cell also needs the precise monitoring and management system FCMS to quickly adjust the relevant parameters of the reaction through the discharge state. In order to store hydrogen, 70MPa high-pressure liquid hydrogen storage tank is generally used.