Journal
ADVANCED ENERGY MATERIALS
Volume 7, Issue 17, Pages -Publisher
WILEY-V C H VERLAG GMBH
DOI: 10.1002/aenm.201700403
Keywords
anodes; hard carbon; mechanism; nanostructures; sodium-ion batteries
Categories
Funding
- U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering [KC020105-FWP12152]
- National Key Research Program of China [2016YFB0901501]
- National Science Foundation of China [21333007, 21373155, 21273090]
- DOE's Office of Biological and Environmental Research
Ask authors/readers for more resources
Hard carbon is one of the most promising anode materials for sodium-ion batteries, but the low Coulombic efficiency is still a key barrier. In this paper, a series of nanostructured hard carbon materials with controlled architectures is synthesized. Using a combination of in situ X-ray diffraction mapping, ex situ nuclear magnetic resonance (NMR), electron paramagnetic resonance, electrochemical techniques, and simulations, an adsorption-intercalation mechanism is established for Na ion storage. During the initial stages of Na insertion, Na ions adsorb on the defect sites of hard carbon with a wide adsorption energy distribution, producing a sloping voltage profile. In the second stage, Na ions intercalate into graphitic layers with suitable spacing to form NaCx compounds similar to the Li ion intercalation process in graphite, producing a flat low voltage plateau. The cation intercalation with a flat voltage plateau should be enhanced and the sloping region should be avoided. Guided by this knowledge, nonporous hard carbon material has been developed which has achieved high reversible capacity and Coulombic efficiency to fulfill practical application.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available