Enhanced Lithium Ion Transport by Superionic Pathways Formed on the Surface of Two-dimensional Structured Li0.85Na0.15V3O8 for High-Performance Lithium Ion Batteries

• Li0.85Na0.15V3O8 nanosheet with superionic conductive layer was constructed.
• LixV2O5 surface layer provides facile pathways for lithium migration.
• LixV2O5-Li0.85Na0.15V3O8 composite displays good high rate capability.

Poor ion transport and rate capability are the main challenges for LiV3O8 as cathode material for lithium ion batteries. Here we report a novel strategy for enhancing lithium ion transport by building superionic pathways on the surface of Li0.85Na0.15V3O8 nanosheet. The two-dimensional Li0.85Na0.15V3O8 nanoparticle with an ion conductive layer of LixV2O5 on its surface is constructed by a modified sol–gel strategy with carefully controlled sodium incorporation and elements stoichiometry. Ultrathin LixV2O5 surface layer not only provides facile pathways for lithium migration, but also increases the structure stability during cycling. The LixV2O5-Li0.85Na0.15V3O8 composite displays good high rate capability of 172.3 mAh g−1 at 5C and excellent cycling stability of 98.9% over fifty cycles. This superior electrochemical property is attributed to the occupation of lithium site by Na+ in LiV3O8 host crystals and the surface superionic pathways of LixV2O5 phase. Therefore, the advantages of both high ion transport and the structure stabilization in present study put forward a new strategy for achieving high-performance LiV3O8 electrode material with tailored nanoarchitecture.