What Is a Fuel Cell Anode?

A fuel cell is a type of cell that generates power by taking a fuel such as hydrogen or natural gas, combining it with an oxidant such as air or oxygen, and converting it into chemical energy. A fuel cell anode is an essential part of the fuel cell that controls the fuel portion of the fuel cell. The fuel cell anode is a positively charged node where hydrogen enters and is then stripped of its electrons. Materials used to make anodes are metals such as platinum, magnesium and titanium.

The process starts with pressurized hydrogen being pumped into the fuel cell anode. The anode, which is positively charged, strips the electrons away from the hydrogen. After the electrons are removed, the hydrogen is considered ionized, meaning it has a positive charge instead of a negative charge.

The electrons pass through an electrolyte layer, either solid or liquid, in the middle of the fuel cell. This layer takes the electrons and passes them on to the cathode. The cathode, which is a negatively charged node, uses oxygen and reacts with the hydrogen electrons to produce electricity. With ionized hydrogen and oxygen together at the cathode, water is created. This water is drained from the fuel cell to complete the process.

As an essential part of the fuel cell, a fuel cell anode has a direct impact on the performance of the entire cell. The most important part of the anode is the surface area, because this is where the hydrogen or fuel reacts with the anode. A fuel cell anode can still be used if the surface area becomes tarnished or needs repairs, but the fuel cell will begin to produce less electricity and heat and, in time, will be unable to produce any energy.

A fuel cell anode is designed with channels and notches etched into it. After the hydrogen is ionized, it has to escape from the fuel cell anode to continue to the rest of the fuel cell process. With these channels, it allows the ionized hydrogen to disperse equally from the anode into the electrolyte layer.

The metal used to make a fuel cell anode varies and produces different results. Some of the common materials used are platinum, titanium and magnesium. Platinum is the most popular because it moves the fastest and has high durability. Titanium is close to platinum but it is cheaper and slightly less durable. Magnesium anodes are known as sacrificial anodes because the magnesium wears away quickly, but this wearing away allows the magnesium to penetrate others parts of the fuel cell to provide protection for those parts.