Developing advanced high-rate electrode materials has been a crucial aspect for next-generation lithium ion batteries (LIBs). A conventional nanoarchitec-turing strategy is suggested to improve the rate performance of materials but inevitably brings about compromise in volumetric energy density, cost, safety, and so on. Here, micro-size Nb14W3O44 is synthesized as a durable high-rate anode material based on a facile and scalable solution combustion method. Aberration-corrected scanning transmission electron microscopy reveals the existence of open and interconnected tunnels in the highly crystalline Nb14W3O44, which ensures facile Li+ diffusion even within micro-size particles. In situ high-energy synchrotron XRD and XANES combined with Raman spec-troscopy and computational simulations clearly reveal a single-phase solid-solution reaction with reversible cationic redox process occurring in the NWO framework due to the low-barrier Li+ intercalation. Therefore, the micro-size Nb14W3O44 exhibits durable and ultrahigh rate capability, i.e., ≈130 mAh g−1at 10 C, after 4000 cycles. Most importantly, the micro-size Nb14W3O44 anode proves its highest practical applicability by the fabrication of a full cell incor-porating with a high-safety LiFePO4 cathode. Such a battery shows a long calendar life of over 1000 cycles and an enhanced thermal stability, which is superior than the current commercial anodes such as Li4Ti5O12.
Read more at Advanced Materials:
https://onlinelibrary.wiley.com/doi/full/10.1002/adma.201905295
19 Feb 2020