Graphite‐Based Composite Anodes with C−O−Nb Heterointerfaces Enable Fast Lithium Storage

Abstract

To better satisfy the increasing demands for electric vehicles, it is crucial to develop fast-charging lithium-ion batteries (LIBs). However, the fast-charging capability of commercial graphite anodes is limited by the sluggish Li + insertion kinetics. Herein, we report a synergistic engineering of uniform nano-sized T-Nb 2 O 5 particles on graphite (Gr@Nb 2 O 5 ) with CÀ OÀ Nb heterointerfaces, which prevents the growth and aggregation of T-Nb 2 O 5 nanoparticles. Through detailed theoretical calculations and pair distribution function analysis, the stable existence of the heterointerfaces is proved, which can accelerate the electron/ion transport. These heterointerfaces endow Gr@Nb 2 O 5 anodes with high ionic conductivity and excellent structural stability. Consequently, Gr@10-Nb 2 O 5 anode, where the mass ratio of T-Nb 2 O 5 /graphite = 10/100, exhibits excellent cyclic stability and incredible rate capabilities, with 100.5 mAh g À 1 after 10000 stable cycles at an ultrahigh rate of 20 C. In addition, the synergistic Li + storage mechanism is revealed by systematic electrochemical characterizations and in situ X-ray diffraction. This work offers new insights to the reasonable design of fastcharging graphite-based anodes for the next generation of LIBs.

Constructing a Stable Integrated Silicon Electrode with Efficient Lithium Storage Performance through Multidimensional Structural Design

“…In eq , a is a constant, and the value of b can be ascertained through the plotting of log( v ) versus log( i ) curves. A b value of 0.5 indicates a diffusion-dominated process, while b = 1.0 suggests a pseudocapacitance-controlled process . The values of b (Figure S12) for I1 (0.91) are higher than I2 (0.87) and I3 (0.85), implying a combined electrochemical kinetic mechanism. , Additionally, the contribution of both the pseudocapacitive and diffusion parts can be quantified using eq : i ( v ) = k 1 v + k 2 v 1 / 2 …”

Accelerating High-Rate Li-Ion Storage in Graphite via a Thin-Layer Coating of Atomic Mo–NC

“…Many strategies have been developed to address the above problems, including structural engineering and porosity management for a shortened Li + transport pathway, , electrolyte regulation for optimal Li + –solvent interaction, − interface engineering for stable SEI formation, lowered desolvation barriers, , and fast charge transfer. , Among them, the interface constructed by graphite/SEI/solvent is of utter importance because it involves several key steps during Li insertion and extraction processes, including Li + desolvation, , Li + migration through SEI, charge transfer at Gr edges, Li + diffusion into Gr, etc. Therefore, it is essential to devote more attention to this specific area and also vital to construct optimal interface modifications of Gr to achieve fast and stable charging of LIBs.…”