A Rhombohedral Li2NaV2(PO4)3/C Nanoflake Cathode for Li-Ion Battery with High Rate Capability and Long Cycle Stability

Rhombohedral Li2NaV2(PO4)3 (LNVP) is an attractive cathode material for lithium-ion battery (LIB) application due to its single voltage plateau at 3.7 V that provides a constant output power. However, only view studies have reported rhombohedral (LNVP) cathode material because it requires a complex route to synthesize. Here, we propose a simple and low-cost pyro-synthesis strategy to develop a rhombohedral LNVP/C nanoflake electrode for useful LIB applications for the first time. When tested in lithium-ion cells, the rhombohedral LNVP/C demonstrated long cycle stability with 100% of the initial discharge capacity retained after 300 cycles. Under long-term cycling, the present cathode showed approximately 99% of Coulombic efficiency. Besides, the realization of specific capacities of 77 and 55 mAh g-1 at current densities as high as 6.4 and 12C, respectively, clearly demonstrates the decent rate capabilities of the prepared rhombohedral LNVP/C electrode. The present study proves to be useful for utilizing the pyro-synthesis process as a straightforward and cost-cutting approach not only to develop nanostructured rhombohedral LNVP/C but also other cathode materials for high performance LIB applications.