Three‐Dimensional Holey Graphene Enwrapped Li<sub>3</sub>V<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub>/N‐Doped Carbon Cathode for High‐Rate and Long‐Life Li‐Ion Batteries
Xiaopeng Li, Xing-Yu Du, Yulin Xu, Jianming Li, Yujue Wang, Yan Meng, Dan Xiao
Abstract
Abstract Monoclinic Li 3 V 2 (PO 4 ) 3 is a promising cathode material for high‐power Li‐ion batteries. Herein, a three‐dimensional holey graphene enwrapped Li 3 V 2 (PO 4 ) 3 /N‐doped carbon (LVPNCHG) nanocomposite has been successfully synthesized. The holes could be in‐situ and directly introduced in graphene through H 2 O 2 chemical etching in the synthesis process, which could remarkably enhance the ion and electron transport and greatly improve the electrochemical performance of the LVPNCHG electrode: 78 mAh g −1 at 150 C, 86.1 % capacity retention over 2000 cycles at 10 C, and 96 % capacity retention over 500 cycles at 1 C under −20 °C. Moreover, in‐situ distribution of relaxation time analysis was used to study LVPNCHG cathode during charge/discharge at 3.0–4.8 V, combined with in‐situ X‐ray diffraction measurement, and the results showed that a two‐phase reaction mechanism was involved during the insertion of Li + in the discharge process. Further demonstration of graphite//LVPNCHG full cell indicated great potential of the as‐synthesized materials for practical application.