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Old 10-25-2018, 03:40 PM   #44 (permalink)
All Darc
Join Date: Feb 2018
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Good question... But I bet it have smaller area, since graphene it's in atomic scale, as it starts as a 1 carbon atom of tichness for each sheet. But many production of grahene today made pieces of grahene, small pieces, and they junk it combined with other things.

Another good would be the limit of energy density growing along cycles. Any limity? In one web article John Goodenough said that in one case a battery got 30x the energy density of good Lithium-ion cells. This 30x it's where I get skeptical too... Maybe it's a battery model with a huge percentage of electrolyte and they didn't count it, but counted only the cathode and anode amounts (compared to amounts of industrial LI-ion cells on market), when calculating the energy density comparisom.
That was a speculation of one skeptic scientist, as he said the lab batteries use to have much electrolyte and very small amounts of reactive material (cathode & anode) to allow fast studies about charge and discharge.

The Graphene supercapasitos I saw in a news about a research would be about 20x the energy density of industrial Li-Ion batteries.

Maria Helena Braga said that are both, a battery and super capacitor, but the super capacitor start to get very relevant after 50 or so cycles, if we look at the graphic :

One funy thing about graphene capacitor it's the way the TV news explains, making people get it wrong. They explaining turn people to undestand that just a single layer of graphene (since graphene starts as 1 layer of carbon atoms in hexagon formation) would be more energy denser than any other battery. They even talked about a grahene car shell being a supercapacitor, and I bet some people understood the shell would have just 1 layer of atoms.

Originally Posted by redpoint5 View Post
Current supercaps are made with graphene, and they have crazy surface area for their size, but can hold about 1.85v max charge.

How does the surface area of this compare with graphene based supercaps?

I'm still not understanding if this is a chemical battery, or a static charge (capacitor)? Granted, I haven't read through the links yet.

Last edited by All Darc; 11-02-2018 at 06:01 PM..
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