A recent study at Kyushu University in Japan has solved a major challenge in the fuel cell field, developing a solid oxide fuel cell that can operate efficiently at 300 degrees Celsius.
Hydrogen energy holds great promise as a climate-friendly energy source, but the technology behind it has often been limited by its high cost and complexity. The challenge lies in the high operating temperatures: to convert hydrogen into electricity and water, these cells typically need to operate between 700 and 800 degrees Celsius. This drives up material costs and hinders their widespread adoption in everyday applications.
Now, a research team at Kyushu University in Japan has achieved a breakthrough that may overcome this obstacle. They have developed a solid oxide fuel cell (SOFC) that can operate efficiently at 300 degrees Celsius. The lead researcher claims that at 300 degrees Celsius, the material costs of the battery will be significantly reduced.
The key to this success lies in a redesigned electrolyte layer. This ceramic layer is capable of conducting positively charged hydrogen ions (protons) through the crystal lattice, allowing them to participate in the power generation process. Normally, this process requires high temperatures to enable the protons to move. However, through the targeted use of chemical additives (i.e., dopants) combined with compatible oxide crystals, the research team successfully achieved proton conduction at lower temperatures.
After extensive testing, the researchers focused on two materials: barium stannat and barium titanate. Both materials are doped with scandium. The study found that scandium atoms form a "broad, vibrationally gentle molecular highway" with oxygen atoms, allowing protons to migrate with extremely low energy barriers. Furthermore, these two materials are softer than traditional electrolytes and more readily absorb dopants.
Although 300°C is still high compared to room temperature, this research is considered a significant advance. It not only reduces operating costs but also potentially paves the way for the wider application of solid oxide fuel cells, from industrial applications to future home appliances.
