Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 13, 2020
Previous Article Next Article

A freestanding hierarchically structured cathode enables high sulfur loading and energy density of flexible Li–S batteries

Author affiliations

Abstract

Due to sulfur agglomeration and drastic volume expansion during charging, a significant challenge for lithium–sulfur battery applications is to achieve favorable energy densities while realizing substantial sulfur loading. The rational design of cathode materials is therefore essential. Here we show a new type of low-cost sulfur/silica/carbon hybrid cathode by integrating carbon-coated and sulfur-encapsulated mesoporous SiO2 nanospheres with a carbon fiber cross-linked graphene framework (denoted as 3D-GCSS). The porous morphology of SiO2 ensures electrolyte accessibility, while the mechanical robustness of graphene and the carbon fiber contributes to structural sturdiness and flexibility. The synergistic effect exerted by polar SiO2 together with conductive graphene and the carbon fiber helps to confine sulfur and intermediate polysulfides as well as providing abundant charge transfer paths. Benefiting from these merits, a coin cell fabricated based on the freestanding 3D-GCSS with an 8 mg cm−2 sulfur content displayed a high capacity of 1462 mA h g−1 at 0.5C, satisfactory rate performance and cycling stability. More importantly, a type of ultra-flexible soft-packaged cell was assembled utilizing the 3D-GCSS electrode. At a considerable sulfur loading of 20 mg cm−2, the battery delivered an outstanding capacity of 2.15 A h, a gravimetric energy density of 371 W h kg−1 (1055 W h kg−1 based on the cathode) and a volumetric energy density of 582 W h l−1.

Graphical abstract: A freestanding hierarchically structured cathode enables high sulfur loading and energy density of flexible Li–S batteries

Back to tab navigation

Supplementary files

Article information


Submitted
31 Dec 2019
Accepted
27 Feb 2020
First published
28 Feb 2020

J. Mater. Chem. A, 2020,8, 6303-6310
Article type
Paper

A freestanding hierarchically structured cathode enables high sulfur loading and energy density of flexible Li–S batteries

J. Liu, Z. Li, B. Jia, J. Zhu, W. Zhu, J. Li, H. Pan, B. Zheng, L. Chen, G. Pezzotti and J. Zhu, J. Mater. Chem. A, 2020, 8, 6303
DOI: 10.1039/C9TA14240A

Social activity

Search articles by author

Spotlight

Advertisements