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Because of the disadvantages of commercial graphite anodes for high-power lithium-ion batteries, a kind of spinel nanolithium titanate (Li4Ti5O12)/graphene microsphere composite [denoted as LTO/reduced graphene oxide (rGO)] is successfully synthesized. The as-prepared composite is made up of curled graphene sheets which are anchored with nano-Li4Ti5O12particles. These nano-Li4Ti5O12particles are uniformly decorated on the conductive graphene framework and their sizes range from just 15 to 20 nm. In the as-prepared composite, the curled graphene sheets form a unique mesopore-oriented structure which provides plenty of three-dimensional channels for ion transportation. These structure characters greatly improve both the electron conductivity and Li+diffusion ability. The ratio of pseudocapacitive capacity dramatically increases in the obtained LTO/rGO composite and generates excellent ultrahigh rate performances. The as-prepared LTO/rGO composite delivers a reversible capacity of 70.3 mA h g–1at 200 C and a capacity retention of 84.7% after 1000 cycles at 50 C. As the current density varies from 30 to 100 C, the special capacity remains unchanged (about 112 mA h g–1). These results show that the graphene framework-supported nano-Li4Ti5O12composite has potential application in high-power lithium-ion batteries.

A lithium–sulfur (Li–S) battery is a promising candidate for an electrochemical energy-storage system. However, for a long time, it suffered from the “shuttle effect” of the intermediate products of soluble polysulfides and safety issues concerning the combustible liquid electrolyte and lithium anode. In this work, sulfide polyacrylonitrile (SPAN) is employed as a solid cycled cathode to resolve the “shuttle effect” fundamentally, a gel polymer electrolyte (GPE) based on poly(ethylene glycol) diacrylate (PEGDA) is matched to the SPAN cathode to minimize the safety concerns, and finally, a quasi-solid-state Li-SPAN battery is combined by an in situ thermal polymerization strategy to improve its adaptability to the existing battery assembly processes. The PEGDA-based GPE achieved at 60 °C for 40 min ensures little damage to the in situ battery, a good electrode–electrolyte interface, a high ionic conductivity of 6.87 × 10–3S cm–1at 30 °C, and a wide electrochemical window of 4.53 V. Ultimately, the as-prepared SPAN composite exerts a specific capacity of 1217.3 mAh g–1after 250 cycles at 0.2 C with a high capacity retention rate of 89.9%. The combination of the SPAN cathode and in situ thermally polymerized PEGDA-based GPE provides a new inspiration for the design of Li-SPAN batteries with both high specific energy and high safety.