Towards a reliable Li-metal-free LiNO_3-free Li-ion polysulphide full cell via parallel interface engineering

摘要

There has been intensive concentration and effort on addressing the notorious challenges of Li-S batteries with respect to polysulphide utilization and lithium dendrite inhibition. However, the search for and optimisation of a Li-metal-free full cell design remain relatively premature in terms of the generic synchronous approach to improve the anode/cathode stability while balancing the anode/cathode capacity. We hereby report a parallel interface engineering (PIE) strategy to enhance the full-cell performance of the Li-ion polysulphide battery. Very importantly, this PIE strategy allows the use of a Li-metal-free anode and a LiNO3-free electrolyte. The cell-level improvement is attributable to more efficient and uniform lithium sulphide deposition on the chemically uniform surfaces of the carbon cathode and suppressed growth of dendritic species on the Li-Al alloy anode with an implantable solid-electrolyte interphase. Quantitative electrochemical alloying for anode fabrication allows increased lithium utilization relative to the total anode capacity. The PIE strategy represents a facile approach to address the troublesome issues of Li-S batteries at the full cell level.