Binder-and Carbon-free Porous Thick Tin Foil Electrode via a Spontaneous Electrochemical and Chemical Process

In this work, a porous Sn foil electrode that is free of binder and conducting agent is prepared for use in lithium ion batteries via a spontaneous method that consists of electrochemical lithiation followed by a chemical de-lithiation process. In lithium ion battery, conventional Sn foil cannot electrochemically accommodate lithium ions despite the low current density of 50 mA/g used for cycling because of the high kinetic hindrances resulting from the poor diffusion of lithium between the electrolyte and the electrode. In this work, the surface morphology of Sn foil is modified to be porous to ensure the lithium diffusion pathway from the electrolyte to the electrode using a facile method that does not require special electrochemical equipment. The obtained porous Sn foil exhibits a voltage plateau that corresponds to Li/Sn alloying and a reversible specific capacity that exceeds 300 mAh/g. The crystal structures, surface morphologies, and electrochemical characteristics of the prepared samples are investigated using X-ray diffraction, scanning electron microscopy, and electrochemical analyses.