A Low Strain A‐Site Deficient Perovskite Lithium Lanthanum Niobate Anode for Superior Li⁺ Storage

Abstract

The oxide perovskite family holds great promise for diverse applications on account of their unique chemical and physical properties. However, owing to the inadequate Li + -storage sites, the insertion-type perovskite anodes for lithium-ion batteries (LIBs) are limited. A-site deficient perovskites with rich intrinsic vacancies and ion transport channels are believed to be the desirable hosts of superior Li + storage. Herein, the perovskite Li 0.1 La 0.3 NbO 3 (LLNO) is designed and demonstrated as the remarkable anode for LIBs with a high specific capacity, a safe operating voltage, an excellent rate performance, and a long cycling life. More importantly, the outstanding cycling stability of LLNO is originated from its low strain characteristic with a maximum volume change of only 1.17%. The exceptional rate performance can be explained by the unconventional Li + transport pathways with external → grain boundaries → lattice deficiencies. These results not only reveal that A-site deficient perovskite LLNO is a promising anode for LIBs but also provide fundamental insights into the Li + ions transport mechanism, facilitating the development of high-performance perovskite anodes.

Layered Perovskite Lithium Yttrium Titanate as a Low‐Potential and Ultrahigh‐Rate Anode for Lithium‐Ion Batteries

“…It is obvious that the rate capacity of LYTO anode significantly surpasses that of the listed titanium‐based anode materials, including the well‐constructed Li 4 Ti 5 O 12 , [ 37 ] graphene functionalized Li 2 TiSiO 5 , [ 38 ] Li 0.5 La 0.5 TiO 3 , [ 39 ] 1D TiNb 2 O 7 nanorods, [ 40 ] and porous nanosized Ti 2 Nb 10 O 29 . [ 41 ] Even compared to several high‐rate niobium‐based anode materials, such as T‐Nb 2 O 5 , [ 23 ] Li 0.1 La 0.3 NbO 3 , [ 42 ] Nb 14 W 3 O 44 , [ 43 ] and Nb 18 W 16 O 93 , [ 20 ] LYTO anode exhibits the comparable rate performance, demonstrating the ultrahigh‐rate properties. Given its irregular submicrometer scale morphology without coating or nanosized treatment, the outstanding rate performance may be attributed to the inherent rapid Li + migration kinetic and low diffusion energy barrier, which will be discussed through several characterizations and simulated calculation.…”

Atomic Short‐Range Order in a Cation‐Deficient Perovskite Anode for Fast‐Charging and Long‐Life Lithium‐Ion Batteries

“…The first four‐cycle cyclic voltammetry (CV) curves of CNO at 0.1 mV s −1 are shown in Figure a, where the anodic/cathodic peak pair at 1.43/1.18 V is attributed to Nb 3+ /Nb 4+ redox couple, and the anodic/cathodic peak pair at 1.81/1.72 V is attributed to Nb 4+ /Nb 5+ couple. [ 20 ] The excellent overlap of the first four‐cycle CV curves indicates the superior cycling stability of CNO. Ex situ XPS characterizations of Nb 3d (Figure S4, Supporting Information) during discharge/charge further confirmed the Nb 5+ /Nb 4+ and Nb 4+ /Nb 3+ redox couples in CNO.…”

“…[1][2][3][4][5][6][7] Among the various options, perovskite-type oxides have attracted wide attention owing to abundant insertion sites for Li + storage/ migration and the capacity to accommodate a wide range of cation sizes and oxidation states inside the framework. [15][16][17][18][19][20] Generally, the representative perovskite-type structure is composed of an MO 6 (M = Ti, [19] Nb, [20] W, [17] and Te [17] ) octahedral framework stabilized by rare-earth atoms (A-site). Originating from the structural features, high ionic conductivity, which is a prerequisite for the application of fast-charging lithium-ion batteries, can be obtained by variations in the concentration of A-site cation vacancies.…”

“…The in situ solid-state battery was fabricated with a well-designed and optimized focused ion beam (FIB) to enable the electrochemical activity of the battery. [20,26,41] Figure 4a displays the SEM image of an in situ solid-state battery composed of a CNO anode, Li 6.4 La 3 Zr 1.4 Ta 6 O 12 (LLZO) solid-state electrolyte, and a LiFePO 4 cathode. The morphology features of the CNO anode can be determined from the low-magnification TEM image, where the image contrast is crystalline diffraction contrast, suggesting the great electrochemical activity of CNO after FIB.…”

“…Owing to the merits of considerable capacity, high safety, sufficient lithium diffusion channel, and excellent cycling stability, niobium‐based oxides with perovskite structures are believed to be remarkably promising anode materials for high‐rate lithium‐ion batteries. [ 20 ] In this work, we report cation‐defective CeNb 3 O 9 (CNO) microsized particles that possess a two‐electron transfer per niobium and a typical perovskite structure containing a NbO 6 octahedral framework stabilized by Ce atoms at the A‐site. The synthesized material without nanoscaling shows excellent rate performance (≈103 mAh g −1 at 60 C) and superior long‐term cyclability (99.6% capacity retention after 2000 charge–discharge cycles at the high current rate of 50 C).…”