Binder-free ultrathin SnS2 with superior reversibility of conversion reaction for high-rate lithium ion batteries

Abstract

To enhance the utilization of active materials and transform the traditional electrode preparation technology, a binder-free ultrathin SnS2 anode for lithium ion batteries is fabricated through a simple magnetron sputtering method. In comparison with the electrode synthesized by solvothermal method and coating process, the binder-free SnS2 electrode presents superior reversibility of conversion reaction due to the shorter ions and electrons transport path and the close contact of the active material with the electrolyte, suggesting a restraining effect on the tin agglomeration, then stabilize the electrode structure, it retains the superior capacity retention of 80% after 200 cycles at 0.5 A g−1 and the high rate capability of 788 mAh g−1 at 5.0 A g−1. The ultratiny SnS2 nanoparticles uniformly arrayed on the substrate and occurred dominant pseudocapacitive effect, guaranteeing its high-rate performance with 967 mAh g−1 at 1.0 A g−1 after 200 cycles. The stable electrode morphology after cycling demonstrates its prospect for lithium ion batteries anode.