.png){kind=icon}
.png){kind=icon}
Return
Predominant Proton Insertion during Electrochemical Cycling of ε-VOPO4 in a Nonaqueous Ca-Ion Electrolyte
.png){kind=icon}
OA
AI
J
H
L
B
A
O
G
N
H
DOI：10.1021/acsenergylett.6c01163.png)
.png){kind=icon}
Original request for help.png){kind=icon}
Share.png){kind=icon}
Save
Abstract
En 中文
Calcium-ion batteries (CIBs) are promising for next-generation energy storage systems. However, many reported Ca-ion storage mechanisms lack direct structural evidence, raising concerns that the observed electrochemistry may instead originate from proton insertion. Herein, we investigate the electrochemical cycling of a VOPO4 electrode in an aprotic Ca electrolyte with trace water to clarify the charge storage mechanism. While electrochemistry, elemental analysis, and X-ray absorption spectroscopy seem to support Ca-ion intercalation in the VOPO4 electrode, X-ray diffraction and electron microscopy unequivocally show proton insertion as the predominant charge storage mechanism. The apparent variation of Ca content in the electrode with the state of charge is attributed to the formation and dissolution of Ca-containing precipitates on the surface of VOPO4 particles. Our work demonstrates the propensity of proton participation in the intercalation reaction in Ca-ion batteries and the necessity of structural evidence in understanding reactions in multivalent electrochemical systems.
Keywords:
Batteries
Calcium
Electrodes
Intercalation
Journal
IF:
18.2
Papers:
5.2K
Citations:
6.6W
Organization
Cited Papers