Effect of Lithium Nitrate (LiNO3) on Lithium Metal Secondary Batteries As a Lithium Metal Stabilizing Electrolyte Additive

Abstract

To realize the successful implementation of the electric vehicles (EVs), the development of advanced lithium secondary batteries having excellent cycle life, high energy density and high power density with low price is prerequisite. To achieve this goal, the conventional active materials such as LiCoO2 and graphite based on the intercalation chemistry, which are used in the commercialized lithium-ion batteries, should be replaced. Although lithium metal has been a promising anode material over four decades, it could not fully used in commercialized secondary battery system due to poor cycle life ascribed to the dendrite formation during repeated operation. To solve this problem, we introduced a novel lithium metal stabilizing electrolyte additive, lithium nitrate (LiNiO3). The effect of LiNiO3 was characterized by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), and X-ray photoelectron spectroscopy (XPS). The cycle performance of coin cells containing 0.3wt% of LiNiO3 revealed an improved cycle performance even at high voltage (3.0~4.5V vs. Li/Li+, C/2) and the rate capability at high current density. We believe this is attributable to the formation of stable solid electrolyte interphase (SEI) layer on the surface of lithium metal during precycling, resulting smaller resistance. Acknowledgements This work was supported by the international Collaborative Energy Technology R&D Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea. (No. 20158510050020). References H. S. Kim. et al. Ionics (2013) 19:1795 – 1802Jing Guo et al. Electrochemistry Communications 51 (2015) 59–63