In-situ transmission electron microscopy observation of conversion reaction in $SnO_2$ nanoparticles using graphene liquid cells

Abstract

Lithium-ion battery is a rechargeable battery where Li ions move forward and backward as battery under-goes charge/discharge. For large capacity and faster recharging for high energy storage and power such as battery in electronic vehicles, development for advanced batteries is necessary and $SnO_2$ nanoparticles has been studied for a promising substitute anode. For such development, precise understanding mechanisms of reactions in lithium-on battery is necessary through in-situ studies. For observation of lithiation in $SnO_2$ nanoparticles, graphene liquid cell transmission electron microscopy (GLC-TEM) was used and the overall lithi-ation process of $SnO_2$ nanoparticles was observed in liquid electrolyte. During lithiation, $SnO_2$ underwent formation of an amorphous shell and phase transition to Sn by dynamic nucleation and growth of Sn along with coalescence. And with ex-situ experiment, in-situ results were supported as their consistency of results. This study is thought to contribute in future design of advanced lithium-ion batteries using $SnO_2$ anodes.