Plane-controlled growth strategy improves electrochemical performance of cobalt-free LiNi0.9Mn0.1O2 cathode

Abstract

The ultra-high nickel-layered cathodes (Ni ​≥ ​90 ​%) has garnered significant attention due to its high specific capacity. However, the widespread application of ultra-high nickel-layered cathodes still suffers limitation by structural instability and poor rate performance. Herein, a crystal-face-induced strategy is proposed to enhance rate and cycling performances of the electrode by constructing rapid Li⁺ diffusion channel and reducing internal grain boundaries of secondary particles. The crystal-face-induced strategy facilitates the growth of {010} lattice plane. Highly exposed {010} planes provide wide-open and unobstructed channels for Li⁺ deintercalation/intercalation, enhances the electrode diffusion kinetics, and thus improves the electrode rate performance. In addition, this strategy promotes the primary particle growth, reduces the grain boundaries of secondary particles and mitigates the electrode/electrolyte interface side reactions, enhancing the structural stability and cycling life of the electrode. Accordingly, the modified sample achieved a reversible specific capacity of 198.3 ​mAh g⁻¹ at 1 ​C (1 ​C ​= ​180 ​mA ​g⁻¹) and maintained a capacity retention rate of 88.5 % after 100 cycles, higher than that of the original sample (73.6 %, 146 ​mAh g⁻¹). At the high rate of 5 ​C, it can maintain a high specific capacity of 178 ​mAh g⁻¹ (capacity retention rate of 99 %) after 150 cycles. This work is a leap in ultra-high nickel-layered cathodes development and provides insights into the design of electrode materials for other batteries.