Influence of the fluoroethylene carbonate on the electrochemical behavior of Bi3Ge4O12 as Lithium-ion anode
Por:
Rodriguez J.R., Belman-Rodriguez C., Aguirre S.B., Aguila S.A., Pol V.G.
Publicada:
1 ene 2022
Resumen:
Systematic ex-situ X-ray diffraction (XRD) characterization and electrochemical study revealed the key roles that the cut-off voltage and fluoroethylene carbonate (FEC) additive play on improving electrochemical performance of the Bi3Ge4O12-based (BGO) electrode. The ex-situ XRD analysis revealed that BGO particles suffer multiphase transitions during the (dis)charge reactions, being observed some phases as Bi2O2.33, BiLi3, Li2O, Ge4Li15, Ge2Li7, Ge3Li7, Ge5Li22, Ge4Li9, Bi2O3 and GeO2. The electrochemical evaluation exhibited that the addition of 5 v/v% of FEC in 1.0 M lithium hexafluorophosphate (LiPF6) in ethylene carbonate and diethyl carbonate (EC: DEC) at an applied cut-off voltage (1.5 V vs Li/Li+) improves the specific capacity (29%, delivering 479 mAh g-1), capacity retention (12%) and rate capability (369 mAh g-1 at 1000 mA g-1) of the BGO-based electrode. Also, FEC promotes the formation of a stable solid-electrolyte interface (SEI) layer on the anode at a cut-off voltage of 1.5 V vs Li/Li+. It displays the lowest values of SEI and charge transfer (CT) resistances, and electrode polarization, improving the reversibility of the alloying reactions related to Ge-Li and Bi-Li and maintaining their redox activity after 100 cycles, according to dQ dV-1 data. © 2022
Filiaciones:
Rodriguez J.R.:
Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, United States
Centro de Investigación Científica y de Educación Superior de Ensenada, BC, Ensenada, 22860, Mexico
Belman-Rodriguez C.:
Centro de Investigación Científica y de Educación Superior de Ensenada, BC, Ensenada, 22860, Mexico
Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, BC, Ensenada, 22860, Mexico
Aguirre S.B.:
Universidad Autónoma de Baja California, Unidad Ensenada, BC, Ensenada, 22860, Mexico
Aguila S.A.:
Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, BC, Ensenada, 22860, Mexico
Pol V.G.:
Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, United States
|