Details

Autor(en) / Beteiligte

• Wang, Hui
• Jiang, Yang
• Manthiram, Arumugam

Titel

Long Cycle Life, Low Self‐Discharge Sodium–Selenium Batteries with High Selenium Loading and Suppressed Polyselenide Shuttling

Ist Teil von

• Advanced energy materials, 2018-03, Vol.8 (7), p.n/a

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2018

Quelle

Wiley Online Library

Beschreibungen/Notizen

• The use of selenium as a cathode in rechargeable sodium–selenium batteries is hampered by low Se loading, inferior electrode kinetics, and polyselenide shuttling between the cathode and anode. Here a high‐performance sodium–selenium cell is presented by coupling a binder‐free, self‐interwoven carbon nanofiber–selenium cathode with a light‐weight carbon‐coated bifunctional separator. With this strategy, electrodes with a high Se mass loading (4.4 mg cm−2) render high reversible capacities of 599 mA h g−1 at 0.1C rate and 382 mA h g−1 at 5C rate. In addition, this novel cell offers good shelf‐life with a low self‐discharge, retaining 93.4% of its initial capacity even after resting for six months. As evidenced by experimental and density functional theory analysis, the remarkable dynamic (cycle life) and static (shelf‐life) stabilities originate from the high electrical conductivity, improved Na‐ion accessibility through the 3D interconnected open channels, and highly restrained polyselenide shuttle. The results demonstrate the viability of high‐performance sodium–selenium batteries with high selenium loading. A novel Na Se cell, assembled by coupling self‐interwoven carbon nanofiber/Se with a carbon‐coated separator displays excellent cycling life stability with a high selenium loading of 4.4 mg cm−2. The cell also retains 93.4% of its initial capacity even after resting for six months, making the NaSe cells competitive for energy storage.