Enhancement of Irreversible Capacity By Pre-Formed Lithium Silicates and Lithium Oxide in Sio Anode for Lithium Ion Battery

This study focuses on effect of improved irreversible capacity in SiO anode. Irreversible phases such as Li₄SiO₄, Li₂SiO_3, Li₂O were synthesized by a solid state reaction using a mixture composed of 70 wt% SiO powder and 10 wt% Li-powder. The mixture was mixed by homogenizer and was heated at 600 °C for 2 h in an argon atmosphere. The irreversible phases were observed by XRD, XPS and TEM. Irreversible phases-formed SiO/lithium metal coin cells (2032) were assembled in a dry room. The discharge-charge cycling was performed with cut-off voltage of 0-1.5V. The electrochemical characteristics of the irreversible phases-formed SiO anode were rationalized through impedance analysis, cycle data and voltage profile. The irreversible phases-formed SiO anode’s capacities were 1265.36 mAh g^-1 (lithiation) and 1052.03 mAh g^-1 (delithiation) after first cycle. The reversible capacity of irreversible phases-formed SiO /lithium metal cells was estimated 83.14% in 1^st cycle. It’s larger than pristine SiO/lithium metal which has 60.08%.