Surface modification of battery electrodes via electroless deposition with improved performance for Na-ion batteries

• Published in: Physical chemistry chemical physics : PCCP Vol. 18; no. 22; pp. 14782 - 14786
• Main Authors: Lahiri, Abhishek, Olschewski, Mark, Gustus, René, Borisenko, Natalia, Endres, Frank
• Format: Journal Article
• Language: English
• Published: England 01.06.2016
• Subjects: Devices; Electrodes; Electroless deposition; Energy storage; Formations; Ionic liquids; Rechargeable batteries; Strategy
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c6cp02364a

Sodium-ion batteries (SIBs) are emerging as potential stationary energy storage devices due to the abundance and low cost of sodium. A simple and energy efficient strategy to develop electrodes for SIBs with a high charge/discharge rate is highly desirable. Here we demonstrate that by surface modification of Ge, using electroless deposition in SbCl3/ionic liquids, the stability and performance of the anode can be improved. This is due to the formation of GexSb1-x at the surface leading to better diffusion of Na, and the formation of a stable twin organic and inorganic SEI which protects the electrode. By judicious control of the surface modification, an improvement in the capacity to between 50% and 300% has been achieved at high current densities (0.83-8.4 A g(-1)) in an ionic liquid electrolyte NaFSI-[Py1,4]FSI. The results clearly demonstrate that an electroless deposition based surface modification strategy in ionic liquids offers exciting opportunities in developing superior energy storage devices.