Carbon coated lithium sulfide particles for lithium battery cathodes

In this paper, we investigated the properties of carbon coated lithium sulfide particles prepared following either a dry coating process or a wet coating process, using, respectively, sucrose or polyacrylonitrile (PAN) as carbon source. X-ray diffraction analysis revealed that the crystalline structure of the pristine Li2S was basically preserved upon both coating processes. The dry coating process (Li2S-C-sucrose) resulted in Li2S particles covered only partially by smaller carbon particles, whereas the wet coating method (Li2S-C-PAN) gave Li2S particles, homogenously decorated with thin carbon flakes. As a result, the cycling performance of Li2S-C based electrodes was significantly improved, particularly for Li2S-C-PAN, for which a coulombic efficiency of more than 99.5% was obtained. (C) 2013 Elsevier B.V. All rights reserved.