Sodium is more abundant and more widely distributed than lithium, making sodium batteries a promising option for storing renewable energy. Their weak point is dendrites, needle-like structures that grow on the anode, shorten battery life and can compromise safety.
Researchers at the Center for Innovation on New Energies (CINE), created by FAPESP and Shell and based at USP, Unicamp and UFSCar, simulated how 22 chemical species interact with imperfect sodium surfaces. They found that the defects act as highly reactive hotspots.
Fluoride-releasing electrolytes form sodium fluoride at those spots, a layer that can seal vulnerable areas and block dendrites. The study, coordinated by Juarez Da Silva of IQSC-USP, recommends testing formulas on realistic rough surfaces rather than perfectly flat models.
