Chemically Oxidized Precursor for Ni-Rich NCA Cathode Synthesis with Improved Performances

Abstract

The NCA, a promising Ni-rich layered lithiated transition metal-oxide cathodes in LIBs, significantly contributes to vehicle electrification to conquer the current global climatic crisis.1 Although Ni-rich cathodes possess high gravimetric energy density, such material experiences severe capacity fading, high impedance growth, and inter-granular crackings are limiting its complete utilization in practical.2 The electrochemically active Ni3+ is highly responsible for its high specific capacity, and it is not easy for the complete oxidation of Ni2+ by the thermal event.3 However, the chemical oxidation method helps to reduce inactive Ni concentration in the precursor. Such synthesized material displays improved half-cell and full-cell performances. In half-cell, the synthesized material initially delivered a specific capacity of 191 mAh g-1 and reached 153 mAh g-1 after 250 cycles at a specific current of C/2. Similarly, the full-cell displays moderate capacity fading from 166 to 139 mAh g-1 after 400 cycles at C/2. The lower capacity in the full-cell could be related to the initial lithium loss at the anode, where such loss compensated in half-cells. The capacity retention and electrode polarization are highly appreciable compared to the NCA obtained from the same precursor without any chemical treatment.