Pyrite-based cathodes for lithium batteries: a systematic study about the effect of the active material?s concentration

M. V. BRACAMONTE; D. BARRACO; G. LENER; P. BERCOFF; E. PRIMO; G. LUQUE

Bologna

Congreso; 69th Annual ISE Meeting; 2018

Pyrite (FeS2) is natural, abundant and non-toxic mineral which is a promising candidate for cathode materials in lithium batteries. Eventhoughtthe pyrite?s theoretical capacity is 894 mAh g−1, FeSsuffers poor cycling stability due to the volume fluctuations, formation of soluble lithiumpolysulfides and poor ionic/electrical conductivity of lithiation products [1,2]. This conversion type cathode with several solution-phasereactions has been poorly analyzed in terms of the effect of amount and source of active material in the electrochemical mechanism.In this work, we report the synthesis of pyrite (FeS22) by high-energy mechanical ball milling of a powder mixture of Fe and S powders in a 1:2ratio. The formation of the FeSphase requires 72 h milling time. After that, a thermal treatment at 350 ºC in vacuum was performed topromote the complete formation of pyrite.2