A new ultrafast superionic Li-conductor: ion dynamics in Li11Si2PS12and comparison with other tetragonal LGPS-type electrolytes

Alexander Kuhn, Oliver Gerbig, Changbao Zhu, Frank Falkenberg, Joachim Maier, Bettina V. Lotsch
2014 Physical Chemistry, Chemical Physics - PCCP  
We report on a new ultrafast solid electrolyte of the composition Li 11 Si 2 PS 12 , which exhibits a higher roomtemperature Li ion diffusivity than the present record holder Li 10 GeP 2 S 12 . We discuss the high-pressure synthesis and ion dynamics of tetragonal Li 11 Si 2 PS 12 , and comparison is made with our investigations of related members of the LMePS family, i.e. electrolytes of the general formula Li 11Àx Me 2Àx P 1+x S 12 with Me = Ge, Sn : Li 10 GeP 2 S 12 , Li 7 GePS 8 , Li 10 SnP
more » ... S 12 . The structure and dynamics were studied with multiple complementary techniques and the macroscopic diffusion could be traced back to fast Li ion hopping in the crystalline lattice. A clear correlation between the diffusivity and the unit cell volume of the LGPS-type electrolytes was observed. † Electronic supplementary information (ESI) available: Experimental, Rietveld refinement results, supplementary tables, NMR relaxometry details, impedance spectroscopy details, determination of electronic transference number, SEM-EDX, electrochemical stability. See
doi:10.1039/c4cp02046d pmid:24916653 fatcat:mnobapmzuzhnjoqzo6tl32uhue