Nb2O5 Coating to Improve the Cyclic Stability and Voltage Decay of Li-Rich Cathode Material for Lithium-Ion Battery

Abstract

The commercialization of lithium manganese oxide (LMO) is seriously hindered by several drawbacks, such as low initial Coulombic efficiency, the degradation of the voltage and capacity during cycling, and the poor rating performance. Developing a simple and scalable synthesis for engineering with surface coating layers is significant and challenging for the commercial prospects of LMO oxides. Herein, we have proposed an efficient engineering strategy with a Nb2O5 coating layer. We dissolved niobate (V) ammonium oxalate hydrate and stoichiometric rich LMO (RLM) in deionized water and stirred constantly. Then, the target product was calcined at high temperature. The discharge capacity of the Nb2O5 coating RLM is increased from 195 mAh·g−1 (the RLM without Nb2O5) to 215 mAh·g−1 at a coating volume ratio of 0.010. The average voltage decay was 4.38 mV/cycle, which was far lower than the 7.50 mV/cycle for the pure LMO. The electrochemical kinetics results indicated that the performance was superior with the buffer engineering by the Nb2O5 coating of RLM, which provided an excellent lithium-ion conduction channel, and improved diffusion kinetics, capacity fading, and voltage decay. This reveals the strong potential of the Nb2O5 coating in the field of cathode materials for lithium-ion batteries.

The role of niobium in layered oxide cathodes for conventional lithium-ion and solid-state batteries

“…dev., n = 3) for LIBs and SSBs, respectively. 42,56,58,74,76,77,79,81,87,97 Despite being a point parroted in introductions as critical to improving LIBs, thermal stability, i.e., onset temperature of exothermic decomposition of a charged CAM, is a factor examined by only two studies, where Nb-based coatings did increase thermal stability by a modest ∼4-5%. 35,56 While small in magnitude, it is a self-described "critical" metric that should be examined when modifications are made to NCMs.…”

Heterointerface Engineered Core-Shell Fe2O3@TiO2 for High-Performance Lithium-Ion Storage

“…By identifying suitable anode materials to enhance capacity and kinetics, LIBs could offer superior energy/power density and broader application prospects. Transition metal oxides (TMOs), especially Fe 2 O 3 with its high theoretical capacity (1007 mAh g −1 ) [12], abundance, strong chemical stability, and eco-friendliness, have attracted considerable interest [13][14][15][16][17][18]. However, the high lithiation potential, significant volume expansion, and side reaction tendencies diminish the feasibility of Fe 2 O 3 as an LIB anode [19].…”