Materials Science & Engineering (MS&E) graduate student Chen Liu, along with former MS&E graduate student Dr. Zehao Cui, and their supervisor, Dr. Arumugam Manthiram, has published a paper that digs into the gasses released during Sodium-Ion Battery (SIB) use. Exploring a variety of possible causes and solutions, the researchers studied when and why gas forms inside SIBs.
They found that SIBs release more gas than traditional lithium-ion batteries because of differences in the chemical bonding in the oxide cathode materials used in them. Adding different elements to the sodium oxide cathode, such as manganese and magnesium, helped to both make the chemical bonding stronger and reduce gas formation. The morphology of the cathode also mattered, as some morphologies with small surface areas led to less gas formation. Interestingly, among the different cathode dopants they tested, lithium was the most effective at reducing gas, making the SIBs behave more like lithium-ion batteries.
The researchers found that the gas mainly came from the breakdown of the liquid electrolyte, which created a thick coating layer on the cathode surface, blocking the intercalation of sodium ions. Using common salt in the electrolyte made the problem even worse by causing extra reactions. These insights can help manufacturers design safer and longer-lasting SIBs.
For more about Liu's research, read "Decoding Gas Evolution Pathways and Interfacial Chemistry in Layered Oxide Cathodes for Safer Sodium-Ion Batteries" in Advanced Energy Materials.
