In-situ lithiation through an ‘injection’ strategy in the pouch type sulfur-graphite battery system

Here we report an ‘injection’ strategy to introduce transportable Li-ion in the metallic Li free sulfur-graphite (S-G) pouch type full cell, which could alleviate the safety issues from Li dendrites. A novel process with organolithium reagent is used to reduce S to Li₂S rapidly during assembling the pouch type full cell. The sublimation property of the side product enables the in-situ injection in the pouch type cell, which will not introduce impurities. In addition, this ‘injection’ strategy avoids the drawbacks from the instability of the Li₂S to moisture, which could largely reduce the production cost and improve the practical energy density of the cell. The injected Li₂S-G battery shows quite stable cyclability with a capacity of 640 mAh g⁻¹ at 0.1 C rate. This in-situ ‘injection’ method provides an effective and practical way to produce Li metal free sulfur Li-ion battery with alleviated safety issues.