Synthesis of a High-Capacity α-Fe<sub>2</sub>O<sub>3</sub>@C Conversion Anode and a High-Voltage LiNi<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub> Spinel Cathode and Their Combination in a Li-Ion Battery
Shuangying Wei, Daniele Di Lecce, Riccardo Messini D’Agostini, Jusef Hassoun
Abstract
High Resolution Image Download MS PowerPoint Slide A Li-conversion α-Fe 2 O 3 @C nanocomposite anode and a high-voltage LiNi 0.5 Mn 1.5 O 4 cathode are synthesized in parallel, characterized, and combined in a Li-ion battery. α-Fe 2 O 3 @C is prepared via annealing of maghemite iron oxide and sucrose under an argon atmosphere and subsequent oxidation in air. The nanocomposite exhibits a satisfactory electrochemical response in a lithium half-cell, delivering almost 900 mA h g –1, as well as a significantly longer cycle life and higher rate capability compared to the bare iron oxide precursor. The LiNi 0.5 Mn 1.5 O 4 cathode, achieved using a modified co-precipitation approach, reveals a well-defined spinel structure without impurities, a sub-micrometrical morphology, and a reversible capacity of ca. 120 mA h g –1 in a lithium half-cell with an operating voltage of 4.8 V. Hence, a lithium-ion battery is assembled by coupling the α-Fe 2 O 3 @C anode with the LiNi 0.5 Mn 1.5 O 4 cathode. This cell operates at about 3.2 V, delivering a stable capacity of 110 mA h g –1 (referred to the cathode mass) with a Coulombic efficiency exceeding 97%. Therefore, this cell is suggested as a promising energy storage system with expected low economic and environmental impacts.