Enhanced Performance of “Flower‐like” Li 4 Ti 5 O 12 Motifs as Anode Materials for High‐Rate Lithium‐Ion Batteries
2015; Wiley; Volume: 8; Issue: 19 Linguagem: Inglês
10.1002/cssc.201500639
ISSN1864-564X
AutoresLei Wang, Yiman Zhang, Megan E. Scofield, Shiyu Yue, Coray McBean, Amy C. Marschilok, Kenneth J. Takeuchi, Esther S. Takeuchi, Stanislaus S. Wong,
Tópico(s)Supercapacitor Materials and Fabrication
ResumoAbstract “Flower‐like” motifs of Li 4 Ti 5 O 12 were synthesized by using a facile and large‐scale hydrothermal process involving unique Ti foil precursors followed by a short, relatively low‐temperature calcination in air. Moreover, a detailed time‐dependent growth mechanism and a reasonable reaction scheme were proposed to clearly illustrate and highlight the structural evolution and subsequent formation of this material. Specifically, the resulting “flower‐like” Li 4 Ti 5 O 12 microspheres consisting of thin nanosheets provide for an enhanced surface area and a reduced lithium‐ion diffusion distance. The high surface areas of the exposed roughened, thin petal‐like component nanosheets are beneficial for the interaction of the electrolyte with Li 4 Ti 5 O 12 , which thereby ultimately provides for improved high‐rate performance and favorable charge/discharge dynamics. Electrochemical studies of the as‐prepared nanostructured Li 4 Ti 5 O 12 clearly revealed their promising potential as an enhanced anode material for lithium‐ion batteries, as they present both excellent rate capabilities (delivering 148, 141, 137, 123, and 60 mAh g −1 under discharge rates of 0.2, 10, 20, 50, and 100 C, at cycles of 50, 55, 60, 65, and 70, respectively) and stable cycling performance (exhibiting a capacity retention of ≈97 % from cycles 10–100, under a discharge rate of 0.2 C, and an impressive capacity retention of ≈87 % by using a more rigorous discharge rate of 20 C from cycles 101–300).
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