![\"Graphene](\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2013\/12\/graphenecork-1.jpg\")
<\/a>Graphene cork made last year by Monash University – lighter than air, able to support over 50,000 times its own weight, and a good conductor of electricity – because of its enormous internal surface area<\/p><\/div>\n
Electrodes made this way and saturated in EBIMF 1 M electrolyte have a specific capacitance of 150 Farads per gram, an energy density of 64 Watt-hours per kilogram and a current density of 5 Amps per gram.<\/p>\n
MIT\u2019s Technology Review<\/a> says, \u201cThat\u2019s almost comparable with lithium-ion batteries, which have an energy density of between 100 and 200 watt-hours per kilogram.\u201d\u00a0 To this editor, that seems more like one-third of current best performers in the lithium battery market, although wildly more energy dense than most supercapacitors.<\/p>\n Of greater interest may be their longevity, with 10,000 charging\/discharge repetitions \u201cwithout a significant reduction in capacitance\u2026 the highest so far reported in the literature,\u201d according to Gwangiu researchers.\u00a0 Their supercapacitor pack also charges in a mere 16 seconds, beating the need to go shopping for long hours while one\u2019s EV refreshes itself.<\/p>\n Kannappan and his team think that, \u201csupercapacitor energy storage devices \u2026 can be scaled up for manufacturing in the near future for electric vehicle applications.\u201d<\/p>\n Their research can be seen in greater depth in their paper<\/a>, \u201cGraphene based Supercapacitors with Improved Specific Capacitance and Fast Charging Time at High Current Density.\u201d<\/p>\n Capillary-like action pulls electrolyte into compressed graphene paper in Monash University process<\/p><\/div>\n The manufacturing side of commercializing these breakthroughs may find a home at Monash University in Australia.\u00a0 There, materials engineers make similar performance claims for their supercapacitor materials that are rolled out in a fashion like that of traditional paper making<\/a>.<\/p>\n Dan Li, head researcher for this effort, says his team\u2019s says his team\u2019s supercapacitors are about 10 times more energy dense than commercial devices, noting energy densities similar to lead-acid batteries.\u00a0 They even use a similar starting point, mixing graphite oxide that\u2019s been reduced to low-grade graphene flakes in a solution of hydrazine and ammonia.\u00a0 \u201cAs the mixture dries, the volatile solvent evaporates, causing capillary action to suck the graphene flakes together, with the electrolyte wedged between each of the flakes. Eventually the engineers are left with something that resembles a black sheet of paper \u2014 millions of layers of graphene, with oodles of charge-carrying electrolyte locked in.\u201d<\/p>\n<\/a>