Hard Carbon Anodes for Na‐Ion Batteries: Toward a Practical Use. Issue 12 (6th October 2015)

• Record Type: Journal Article
• Authors: Hasegawa, George; Kanamori, Kazuyoshi; Kannari, Naokatsu; Ozaki, Jun‐ichi; Nakanishi, Kazuki; Abe, Takeshi
• Is Part Of: ChemElectroChem. Volume 2:Issue 12(2015)
• Page Start: 1917
• Page End: 1920
• Publication Date: 2015-10-06
• Subjects: carbon -- coulombic efficiency -- porous electrodes -- sodium -- sol-gel processes; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.201500412
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: Hard carbons have immense potential as anode materials for Na‐ion batteries, because the expanded graphene interlayers and nanovoids between randomly stacked aromatic fragments can accommodate a substantial amount of sodium. However, the large irreversible capacity in the first cycle still remains as a significant issue in terms of a practicable battery technology. Here, we show that hard carbon electrodes derived from a common phenol resin deliver a high reversible capacity within the narrow potential range of 0.1–0.005 V (vs. Na + /Na) and an excellent initial coulombic efficiency up to 95 %. The former allows the sustainable high voltage, whereas the latter minimizes the amount of unavailable Na + in a closed cell. The findings in this work put forward a guideline for manufacturing hard carbon electrodes, which goes against the current trend of nanostructuring and downsizing. Abstract : It's got potential : Carbon electrodes derived from a phenol resin for Na‐ion batteries show potential profiles just like those of Li‐ion intercalation/extraction into/from graphite. The high reversible capacity and the excellent initial coulombic efficiency well above 90 % have great potential for a practical use.