Manipulating Li3V2(PO4)3 cathode grains and conductivity with halloysite nanotubes and carbon layer toward durable lithium ion batteries

Abstract

AbstractAs an olivine‐based cathode with high discharge platform and theoretical capacity, Li3V2(PO4)3's (LVP's) low conductivity and excessive grain size are the important factors hindering its development in the battery field. Halloysite nanotubes (HNTs) is a natural and cheap nanotube‐like material with large specific surface area and abundant surface nucleation sites, which can cooperate with conductive carbon layer to solve the deficiency of LVP. In this paper, we design a cathode material for in‐situ growth of LVP on HNTs (LVP@HNTs) and demonstrate that it has the appropriate particle size and the excellent specific surface area in the mass ratio of LVP to HNTs is 2:1. The capacity retention rate of LVP@HNTs‐2 reached almost 100% (97.0 mAh g−1) after 100 cycles at a low rate of 0.5 C. Moreover, its specific discharge capacity is 89.3 mAh g−1 at a high rate of 20 C and its capacity retention rate is as high as 90.1% (80.5 mAh g−1) after 5,000 cycles, showing that the LVP@HNTs‐2 has marvelous rate capability and cycle stability. This study provides an innovative strategy for the development of the high‐performance cathode materials with low‐cost, excellent rate capability, and cycle stability of lithium ion batteries.