Lithium sulfur battery has become a hot research field due to its high theoretical energy density, low cost and environmental friendliness. However, most of the high capacity and long cycle lithium sulfur batteries have been reported, which can not meet the needs of practical applications. In order to solve the above problems, Fang et al prepared a graphene lithium sulfur battery cathode, with porosity of porous graphene 3.51cm3g-1 (HPG) load active substance sulfur, calcium carbide and high conductivity of graphene (HCG) as collector, graphene oxide (POG) as part of the multi sulfur adsorption layer, load up to 80%, the surface density of 5mgcm-2.
Preparation of HPG: preparation of HPG by thermal exfoliation of graphite oxide. Firstly, the graphite oxide was oxidized by the improved Hummer method. Then the graphite oxide in the air, 300 degrees heat stripped for about 5 minutes, and then in the Ar atmosphere at a temperature of 2 C /min to heat up to the temperature of 1000 degrees, to maintain the, that is, HPG. The mixture of HPG and S was mixed with 1:4 for 30 minutes, and then moved into the hot water kettle for a period of 15 hours, and the S/HPG composite was obtained for 155 hours.
Preparation of POG adsorption layer: GO suspension freeze drying to obtain GO powder, GO powder with the heating rate at 2 for /min to 1000 DEG C for 2 hours, POG, then dispersed in ethanol, ultrasonic for 20 minutes, to the commercial vacuum diaphragm, in the air, dry 24 hours dry under 60 DEG C.
The obtained graphene anode, because HCG is lighter, so improving the energy density of the whole battery, POG and polysulfide by chemical bond, inhibit the shuttle effect polysulfides, even after 400 cycles, the battery still has stable cycle performance, provides a solution for a lithium sulfur battery reliable, which cal also be applied for lithium ion for solar,lithium ion batteries for off grid solar,lithium battery systems,lithium ion battery for inverter,lithium ion battery cells,lithium ion charging circuit,lithium ion deep cycle battery,lithium ion battery for cars,lithium ion battery storage systems,lithium ion 12v battery