Abstract
Transition metal oxides are important conversion-type anodes in lithium ion batteries because of their low cost and high specific capacity. However, the poor conversion-reaction reversibility leads to low coulombic efficiency, sluggish reaction kinetics and unsatisfactory long-term cycling stability, thus severely hindering their practical applications. In this research, we propose a facile strategy to achieve highly reversible lithium storage in a ZnCo2O4 anode by coating ultrafine NiCl2-xFx hydrate on porous ZnCo2O4 microspheres. The intimate and well-distributed contact between two components significantly enhances the activity of the reversible conversion reaction. The NiCl2-xFx hydrate also promotes the reversible decomposition of organic components in the as-formed solid electrolyte interface, evidenced from several microstructural analyses. Moreover, the ultrafine hydrated NiCl2-xFx effectively pins ZnCo2O4 to inhibit the detrimental grain coarsening process during cycling. As a result, the hybrid anode shows significantly increased initial coulombic efficiency from 69.1% to 83%, and the round-trip energy efficiency from 50% to 58.7%. It also demonstrates excellent rate capability and superior cycling stability.
Original language | English |
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Pages (from-to) | 2356-2363 |
Number of pages | 8 |
Journal | Journal of Materials Chemistry A |
Volume | 8 |
Issue number | 5 |
DOIs | |
Publication status | Published - Jan 2020 |
Externally published | Yes |
ASJC Scopus subject areas
- General Chemistry
- Renewable Energy, Sustainability and the Environment
- General Materials Science