Advances on Defect Engineering of Niobium Pentoxide for Electrochemical Energy Storage

Small, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 22, 2025

Abstract The reasonable design of advanced anode materials for electrochemical energy storage (EES) devices is crucial in expediting the progress renewable technologies. Nb 2 O 5 has attracted increasing research attention as an candidate. Defect engineering regarded a feasible approach to modulate local atomic configurations within . Therefore, introducing defects into considered be promising way enhance performance. However, there no systematic review on defect process. This systematically analyzes first crystal structures and mechanisms Subsequently, systematical summary latest advances EES presented, mainly focusing vacancy modulation, ion doping, planar defects, porosity, amorphization. Of particular note effects : improving electronic conductivity, accelerating diffusion, maintaining structural stability, active sites. further summarizes diverse methodologies inducing commonly used techniques characterization In conclusion, article proposes current challenges outlines future development prospects achieve high‐performance with both high power densities.

Language: Английский

Improving Cyclability and Structural Stability of Co‐Free Layered Cathode by Controlling Porosity and Cracks in Secondary Particles for Low‐Cost and High‐Energy LIBs

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 13, 2025

Abstract The Co‐free Li[Ni 0.75 Mn 0.25 ]O 2 (NM7525) cathode offers the significant advantage of low production costs. However, it requires a high‐voltage charging process (≥4.5 V vs Li/Li⁺) to achieve energy density level high‐Ni x Co y z ( ≥ 0.8) cathodes, which leads severe structural and morphological degradation in secondary particles during prolonged cycling. Herein, is demonstrated that formation stable homogeneous cathode‐electrolyte interface (CEI) can effectively suppress large porosity crack propagation NM7525 cathode, as well undesirable changes microstrain crystal structure, with high cut‐off voltage 4.45 an elevated temperature 45 °C full‐cell system. For stabilization CEI layer at operation, optimized electrolyte system applied, containing additive highest occupied molecular orbital (HOMO) energy. This controlled enhances electrochemical performances NM7525‐based full cell. In case cyclability, CEI‐stabilized delivers high‐capacity retention 90% after 100 cycles under harsh operation conditions temperature, whereas as‐prepared shows just 78%.

Language: Английский

Revealing Irradiation-Induced Dynamic Structural Failure in LiCoO₂ Cathodes via Electron-Temperature-Dependent Deep Potential Molecular Dynamics

The Journal of Physical Chemistry Letters, Journal Year: 2025, Volume and Issue: unknown, P. 4155 - 4161

Published: April 18, 2025

In lithium-ion batteries (LIBs) used for deep-space exploration, LiCoO2 cathode materials face significant challenges in high-radiation environments, including structural degradation and ion migration. This study investigates the dynamic evolution of under irradiation using electron-temperature-dependent deep potential (ETD-DP) model. Compared with traditional ab initio molecular dynamics (AIMD) simulations, ETD-DP method extends both spatial temporal scales by several orders magnitude. The results reveal that LiCoO2's response to occurs on nanosecond time scale, divided into three stages: traversal, intense local adjustment, structure relaxation. During adjustment stage, induces migration transition metal ions toward lithium layers. relaxation cobalt displaced from their equilibrium positions form a dumbbell adjacent Co ions. simulation were validated through high-energy electron beam experiments aberration-corrected microscopy. provides valuable insights improving tolerance LIB offers new perspectives application particle-beam-based fine characterization techniques advanced battery applications.

Language: Английский