Silicon anode design for Li ion batteries: Synergic effects of Ag nanoparticles and ionic liquid electrolytes

Abstract

The infinite volume expansion and subsequent stability issues of Si and other alloy-based anodes have relentlessly hindered their application in Li-ion batteries. Moreover, the highly inflammable conventional organic electrolytes have always raised serious safety concerns for Li secondary batteries. In the present study, a novel electrode design based on porous Si nanostructures is demonstrated for application in stable Li-ion batteries to enhance the performance. Silver nanoparticles are embedded within the silicon aerogel-based structures in a viable approach and used in combination with room temperature ionic liquid (RTIL) electrolytes. The mechanical, as well as electrochemical properties of Si anode, were found to be significantly improved with high rate performance as well as cyclic stability. A discharge capacity as high as 2712 mA h g−1 was obtained, maintains a value of 1899 mA h g−1 at the end of 100 cycles at 100 mA g−1.

Keywords

• Li-ion battery
• Silicon anode
• Silver nanoparticle
• Ionic liquid electrolyte
• Aerogel