Graphene-enhanced supercapacitor cells from Skeleton far outperformed the other cells tested. They use curved graphene to increase the efficiency of the cells by reducing the amount of energy that is lost as heat.
“A study led by John Heinzel from the US Naval Surface Warfare Center in Philadelphia, along with researchers at the University of Texas at Arlington, has compared the performance of supercapacitors from four different manufacturers: Maxwell, Ioxus, JM Energy, and Skeleton.
The team studied cells from the four different manufacturers under high pulsed load conditions to measure their power density into low-impedance loads. The researchers found that the Skeleton cell far outperformed the other cells tested, and graphene was mentioned as the probable cause for this efficiency.
The researchers commented: “Its [the Skeleton cell] ESR was less than half of any of the other cells tested, and its power density is more than 10-kW/kg higher than the others.
Skeleton’s superior results are likely due to their use of curved graphene instead of the activated carbon that the other manufacturers use.
This advancement in the energy storage technology will allow for the construction of energy systems that can supply more power to transient loads and allow for the reduction in the size of existing systems.
It also allows for more efficient energy storage systems due to the cell’s low ESR. Future testing will include repetitive pulsing that will be used to compare the amount of energy lost as heat for each cell due to their ESR”.
“At the heart of our ultracapacitors’ performance advantage is Skeleton’s nanotechnology research into patented curved graphene. Curved graphene differs significantly from regular activated carbons, which are used by other ultracapacitor manufacturers. All competitors use organic pre-cursor materials, mostly carbon made from coconut, Skeleton is the only company to use an inorganic pre-cursor and has patented the synthesis process for the proprietary material. The use of curved graphene is one of the key factors in achieving the superior energy density of our ultracapacitors.
Skeleton Technologies has also achieved one of the lowest ESR (equivalent series resistance) levels on the market. This factor is crucial as it greatly increases the efficiency of the cells by reducing the amount of energy that is lost as heat. This is also an advantage because cooling systems can be downsized or removed altogether.”
Read more about ultracapacitor technology over here.
Source: Graphene Info