An Advanced Lithium‐Ion Sulfur Battery for High Energy Storage

A lithium‐ion battery is reported using a sulfur–carbon composite cathode, a graphite anode, and a dimethoxyethane‐dioxolane‐lithium bis‐(trifluoromethanesulfonyl)imide (DOL‐DME‐LiTFSI) electrolyte advantageously added by lithium nitrate (LiNO 3 ) and a selected polysulfide (Li 2 S 8 ). The suppressed sulfur dissolution, due to the Li 2 S 8 buffer action, as well as reduced shuttle reactions by the film‐forming properties of the LiNO 3 positively affect the lithium‐ion cell behavior in terms of delivered capacity, coulombic efficiency, and cycle life. The lithium–sulfur cell shows a stable capacity of 750 mAh g −1 for over 200 cycles with an enhanced cycling efficiency. Furthermore, the full lithium‐ion sulfur battery using a graphite‐based anode shows a working voltage of about 2 V and delivers a stable capacity of 500 mAh g −1 . The full cell has enhanced safety content, due to the replacement of the lithium metal anode by suitable intercalation electrode, and shows a theoretical energy density as high as 1000 Wh kg −1 at high current rate of 1 C. The remarkable safety level, low materials cost, and high practical energy density, expected to exceed 300 Wh kg −1 , suggest the battery reported is a suitable energy storage system for future applications.