LAUSR

Perovskite-type oxides are widely used for energy conversion and storage, but the rate-inhibiting phase transition and large volume change hinder the applications of most perovskite-type oxides for high-rate electrochemical energy storage. Here, we show that a cation-deficient perovskite CeNb3 O9 (CNO) can store a sufficient amount of lithium at a high charge/discharge rate, even when the sizes of the synthesized particles are on the order of micrometers. At 60 C (15 A g-1 ), corresponding to a one-minute charge, the CNO anode delivered over 52.8 percent of its capacity. In addition, the CNO anode material exhibited 96.6% capacity retention after 2000 charge-discharge cycles at 50 C (12.5 A g-1 ), indicating exceptional long-term cycling stability at high rates. The excellent cycling performance is attributed to the formation of atomic short-range order which significantly prevents local and long-range structural rearrangements, stabilizing the host structure and being responsible for the small volume evolution. Moreover, the extremely high rate capacity can be explained by the intrinsically large interstitial sites in multiple directions, intercalation pseudocapacitance, atomic short-range order and cation vacancy-enhanced three-dimensional-conduction networks for lithium ions. These structural characteristics and mechanisms can be used to design advanced perovskite electrode materials for fast-charging and long-life lithium-ion batteries. This article is protected by copyright. All rights reserved.