Electrochemical performance of n-type Cu2O anode material synthesized by electrodeposition method for rechargeable lithium- ion batteries

Abstract

Recently, Cu2O has received more attention for the anode application of the rechargeable Lithium-Ion Battery (LIB) than the other competing materials because of its high theoretical capacity (375 mAhg-1), good capacity retention, affordability, non-toxicity, and ease of storage. The electrochemical performance of Cu2O typically depends on its crystallinity and morphology, which significantly based on the synthesizing technique. However, a simple and convenient electrodeposition technique, which can improve crystallinity with favorable morphology for electrode materials, has not yet been studied for synthesizing Cu2O. Hence, this study aims for preparing n-type Cu2O anode materials by the electrodeposition method with enhanced crystallinity and morphology. The lithium-ion rechargeable coin cells were assembled in an argon-filled glove box with anodes fabricated with synthesized Cu2O, lithium as the reference electrode and counter electrodes together with the non-aqueous electrolyte of 1M LiPF6 in ethylene carbonate and dimethyl carbonate (1:1 wt%). The assembled coin cells subjected to galvanostatic charge-discharge testings revealed a significantly high initial specific discharge capacity of 623.9 mAhg-1 at a rate of 0.2C. That is even after it reported a higher irreversible capacity of 395.4 mAhg-1 at the first cycle. Moreover, it displayed a discharge capacity of 200.3 mAhg-1 and a noticeably lower irreversible capacity of 2.6 mAhg-1 even after 50 cycles. The improved electrochemical performance can mainly be ascribed for the enhanced contact surface area for Cu2O and electrolyte. It could have resulted due to the enhanced contact between Cu2O and electrolyte by decreasing diffusion lengths for lithium ions. Electrochemical impedance spectroscopy and cyclic voltammetry analyses also provided evidences for improved electrochemical performance. Altogether, this study reveals that n-type Cu2O synthesized by electrodeposition method processes very promising electrochemical performance for the anode application of LIB. Hence, this study reveals that Cu2O synthesized by simple, cost-effective, electrodeposition method has very promising electrochemical performance for the anode application of next-generation high-performance LIBs.