Fuel Cell Principle?

[LaWeston]

Fuel cell principle involves an electrochemical reaction between hydrogen and oxygen through an electrolyte, creating a potential difference that results in low-voltage DC output. Working principle of fuel cells: Primary fuels such as natural gas, petroleum, and methanol act as reactants. After hydrogen is separated via a "fuel reforming device," it enters the battery body. Simultaneously, oxygen from the air at the other end also enters the battery body, supplying the electrodes respectively. Through the electrolyte, hydrogen and oxygen undergo an electrochemical reaction, generating a potential difference that produces low-voltage DC output. Main fuels: Fuel cells mainly consist of fuel, oxidizer, electrodes, and electrolyte. The fuels used are highly diverse, including natural gas, petroleum, methanol, liquid ammonia, hydrazine, hydrocarbons, hydrogen, etc. The capacity of such batteries can be designed according to requirements, primarily depending on the number of "single cells."

[LeAna]

I've researched this, and fuel cells are actually quite fascinating. Essentially, they are continuous power generation devices that produce electricity through an electrochemical reaction between hydrogen and oxygen. Imagine the battery pack in a car: hydrogen enters from one side and decomposes into electrons and protons at the negative electrode catalyst. The protons pass through a special membrane to the positive electrode side, while the electrons go to drive the electric motor. On the positive electrode side, oxygen combines with protons and electrons to form water vapor, which is then expelled—resulting in zero emissions throughout the process, making it very eco-friendly. The Toyota Mirai currently uses this type of technology, where refueling with hydrogen takes just three minutes and can cover over 800 kilometers. The only drawback is that hydrogen refueling stations are still limited. The reaction efficiency is two to three times higher than that of an internal combustion engine, and the only emission while driving is water vapor, causing absolutely no environmental pollution.

[Roberto]

The operating mechanism of fuel cells converts chemical energy directly into electrical energy, which is much more efficient than traditional combustion. I've taken apart schematic diagrams, and the core component is that proton exchange membrane. Hydrogen molecules are catalytically split into protons and electrons at the negative electrode. The positively charged protons can penetrate this membrane, but electrons have to travel through an external circuit to generate current. At the positive electrode, protons recombine with oxygen and electrons to form water. The greatest advantage of this technology is its quiet and clean operation - only the water pump and air compressor make slight noises during operation, and you can even touch the exhaust port with your bare hand without getting burned. German truck manufacturers are now using it to replace diesel engines for long-haul transportation.

[RileyAnn]

Wondering why hydrogen fuel cell vehicles have no exhaust? It's because their working substances are hydrogen and oxygen. The hydrogen stored in the fuel tank enters the negative electrode of the fuel cell stack, where it is decomposed by platinum catalysts into positively charged hydrogen ions and negatively charged electrons. The hydrogen ions pass through the electrolyte membrane to reach the positive electrode, while the electrons are forced to travel through an external circuit to power the motor. At the positive electrode, oxygen from the air waits to take electrons from the hydrogen ions, ultimately combining to form pure water that is expelled from the vehicle. This process is equivalent to converting chemical energy directly into electrical energy, with a conversion efficiency as high as 60%, more than double that of gasoline-powered vehicles. Currently, shuttle buses at the Winter Olympics utilize this zero-emission technology.

[CalebAnn]

From a material perspective, the core of a fuel cell is a three-layer structure: two electrodes sandwiching an electrolyte membrane. I've witnessed the factory production process where platinum catalyst is first sprayed onto carbon paper to create the gas diffusion layer, which is then pressed onto the crucial perfluorosulfonic acid proton exchange membrane. When hydrogen is introduced at the anode, it's catalytically dissociated, with hydrogen ions passing through the thin membrane to react with oxygen at the cathode while electrons are forced to travel through the external circuit. The flow channel design on bipolar plates is particularly meticulous, requiring even distribution of hydrogen and oxygen gases. Operating at around 80°C provides stability, but platinum catalyst activity decreases at low temperatures, necessitating preheating during winter startups.