Electrochemical properties of cobalt hydroxychloride microspheres as a new anode material for Li-ion batteries

Abstract

The use of cobalt hydroxychloride [Co2(OH)3Cl] as an anode material for lithium ion batteries (LIBs) is investigated using spherical shape and ultrafine nanocrystals directly formed by spray pyrolysis from spray solution of cobalt chloride salt. Dot-mapping images of the resulting powders reveal a uniform distribution of Co, O, and Cl throughout the powder. The Co2(OH)3Cl powder prepared directly by spray pyrolysis exhibits a high thermal stability at temperatures below 220°C, as well as having superior electrochemical properties compared with those of the CoCl2(H2O)2 and CoO powders prepared by the same process. The initial discharge capacities of the Co2(OH)3Cl and CoO powders at a constant current density of 1000 mA g−1 are found to be 1570 and 1142 mA h g−1, respectively, and their initial Coulombic efficiencies are 72 and 70%. The discharge capacities of the Co2(OH)3Cl and CoO powders after 100 cycles are 955 and 632 mA h g−1, respectively. The Co2(OH)3Cl powders have a high discharge capacity of 609 mA h g−1 even after 1000 cycles at a high current density of 5000 mA g−1.

Superior electrochemical properties of spherical-like Co2(OH)3Cl-reduced graphene oxide composite powders with ultrafine nanocrystals

“…Compositionally, Co 2 (OH) 3 Cl is a solid solution of Co(OH) 2 and CoCl 2 [38,48]. Therefore, the reduction peaks correspond to the conversion of Co(OH) 2 and CoCl 2 into Co nanocrystals, LiOH and LiCl, respectively [38,49,50]. The new reduction peaks observed at around 1.78 V during the second discharge originated from the conversion of amorphous Co(OH) 2 and CoCl 2 formed during the initial cycles [38,49,50].…”

“…The main reduction peaks in the Co 2 (OH) 3 Cl/RGO and CoCl 2 AE6H 2 O/RGO composite powders upon initial discharge were observed at 0.92 and 0.97 V, respectively. Compositionally, Co 2 (OH) 3 Cl is a solid solution of Co(OH) 2 and CoCl 2 [38,48]. Therefore, the reduction peaks correspond to the conversion of Co(OH) 2 and CoCl 2 into Co nanocrystals, LiOH and LiCl, respectively [38,49,50].…”

“…Therefore, the reduction peaks correspond to the conversion of Co(OH) 2 and CoCl 2 into Co nanocrystals, LiOH and LiCl, respectively [38,49,50]. The new reduction peaks observed at around 1.78 V during the second discharge originated from the conversion of amorphous Co(OH) 2 and CoCl 2 formed during the initial cycles [38,49,50]. The voltammograms of the pure-Co 3 O 4 powder electrodes had a distinct reduction peak at 0.84 V during the initial discharge due to the formation of Co nanoclusters and amorphous Li 2 O [51].…”

“…11.039 0008-6223/Ó 2014 Elsevier Ltd. All rights reserved. materials [37,38]. Kim et al showed that copper hydroxychloride (Cu 2 (OH) 3 Cl) is a promising electrode material [37].…”

“…Kim et al showed that copper hydroxychloride (Cu 2 (OH) 3 Cl) is a promising electrode material [37]. Cobalt hydroxychloride (Co 2 (OH) 3 Cl) powders prepared by spray pyrolysis also possess electrochemical properties beneficial for anodes [38]. Bare Co 2 (OH) 3 Cl powders containing CoCl 2 (H 2 O) 2 and CoO impurity phases possess a high capacity of 955 mA h g À1 at a current density of 1000 mA g À1 , but bare Co 2 (OH) 3 Cl powders prepared using a one-pot spray pyrolysis process contained some impurities.…”