Enhanced electrochemical performance of FeS coated by Ag as anode for lithium-ion batteries

Highlights: ► The FeS and FeS/Ag composite are successfully prepared with a facile electroless deposition method. ► The improved cycling stability is ascribed to the suppression of the volume expansion after Ag coating. ► The improved rate ability is ascribed to the enhanced electronic conductivity of Li2S after Ag coating. - Abstract: The Ag coated FeS composite is synthesized via a facile electroless deposition method. The as-prepared FeS/Ag composite shows an initial reversible specific capacity of 533.4 mAh/g and its capacity retention is 79.1% after 55 cycles at different current densities (from 0.1 C to 2 C). In contrast, the initial reversible and capacity retention of pristine FeS tested at the same conditions are 425.8 mAh/g and 29.1%, respectively. The improved reversible capacity and cyclic performance are ascribed to the coated Ag improving the electronic conductivity of the Li2S during its charge process and the suppression of the volume change of FeS anode during its discharge process, respectively.