A long-life, high-rate lithium sulfur (Li/S) cell with high specific energy uniquely combines cetyltrimethyl ammonium bromide (CTAB)-modified sulfur-graphene oxide (S-GO) nanocomposites with an elastomeric styrene butadiene rubber (SBR)/carboxy methyl cellulose (CMC) binder and an ionic liquid-based novel electrolyte with the LiNO.sub.3 additive. A Li/S cell employing a CTAB-modified S-GO nanocomposite cathode can be discharged at rates as high as 6C (1C=1.675 A/g of sulfur) and charged at rates as high as 3C while still maintaining high specific capacity (.about.800 mAh/g of sulfur at 6C), with a long cycle life exceeding 1500 cycles, the longest cycle life with extremely low decay rate (0.039% per cycle) demonstrated so far for a Li/S cell.
STATEMENT OF GOVERNMENTAL SUPPORT
 The invention described and claimed herein was made in part utilizing funds supplied by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The government has certain rights in this invention.