Lithium–sulphur batteries – binder free carbon nanotubes electrode examined with various electrolytes

• Published in: Journal of power sources 2012-09, Vol.213, p.239-248
• Main Authors: Hagen, M., Dörfler, S., Althues, H., Tübke, J., Hoffmann, M.J., Kaskel, S., Pinkwart, K.
• Format: Article
• Language: English
• Subjects: Applied sciences; Battery; Binder free; CNT; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Ionic liquid; Lithium–sulphur; Solid electrolyte
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2012.04.004

A new type of electrode for lithium–sulphur batteries is introduced based on vertical-aligned carbon nanotubes (CNTs) grown on a nickel foil without any binder. The electrodes are synthesized by employing a catalyst layer and a CVD process. The CNTs directly synthesized on the Ni current collector are sulphur infiltrated using different approaches and the results are examined by SEM. Furthermore, cycle tests (1.0–3.0 V) with various electrolytes (liquid organic, ionic liquid and solid) are performed. The binder free CNT cathodes contain the highest so far published total ratio of sulphur (90%) in the electrode. Additionally the sulphur mass per cm² electrode can be more than three times as high as in regular slurry-based sulphur electrodes, thus doubling the volumetric energy density. ► Binder free sulphur cathodes based on CNT for Li–S batteries. ► Sulphur fraction in the electrode of 90%. ► Volumetric energy density doubled in comparison to regular S electrodes. ► Different sulphur infiltration methods of the CNT electrodes were examined. ► Sulphur infiltrated electrodes were examined vs. lithium with various electrolytes.