Electrochemical Analysis of the Effect of Cr Coating the LiV3O8 Cathode in a Lithium Ion Battery with a Lithium Powder Anode

摘要

Rechargeable 2032-coin-type cells were produced with Li-powder anodes (i.e., Li-powder electrodes, LPEs) and either Cr-coated lithium trivanadate (Li_(1+x)V3O8, LVO) cathodes or uncoated LVO cathodes. The initial discharge capacity of a cell with an LPE and a Cr-coated LVO cathode (Cell_(coated)) was 252 mAh g~(-1) at a 0,2 C-rate and that of a cell with an LPE and an uncoated LVO cathode (Cell_(bare)) was 223 mAh g~(-1). After the 50th cycle, Cell_(coated) exhibited higher capacity retention (about 89%) than Cell_(bare) (about 78%). Changes in the surface morphology of the Cr-coated LVO cathode were observed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The change in the electrical conductivity of the cell was measured using the impedance analysis. The electrochemical properties of the cells were also evaluated based on the differential capacity curve, voltage profiles, and capacity versus number of cycles.