While I love the ingenuity of this system, I have some trouble seeing it used as an economically viable energy storage option. According to the article, they would need about 45 m3 to store 10 kwh. At a concrete price of 200-300 $/m3, that would come to 9-13.5k USD just for the concrete. That's omitting any costs for the carbon black electrolyte, material processing, electrolyte separators and other things, so a very optimistic estimate.
Meanwhile, battery prices have fallen so much that you can buy 10 kwh of Li-Ion batteries for about $1500 ($150/kwh 2021 prices). The saving grace might be to have it do double duty as a structural element in the building, but many other posters have pointed out that there are many safety and construction problems that would have to be solved for that first.
It might also turn out that lime for the concrete will become a rate limiting material. Not to mention the energy cost involved in mining both it and creating the carbon nanopowder.
But, a material with similar hydration properties to concrete, a biopolymer for instance, might exist and be made with less cost...
We actually have to start thinking about replacing concrete with something else to be more energy efficient and sustainable.
Raw concrete price in USA is closer to 150$/m3, often less.
One thing we don’t know is life expectancy vs Li-ion, whose 10-year charge is ~60%.
I haven’t read the paper; one thing that’ll also be interesting is operating temperatures. This could be a massive upside to concrete supercaps in certain parts of the globe.
Meanwhile, battery prices have fallen so much that you can buy 10 kwh of Li-Ion batteries for about $1500 ($150/kwh 2021 prices). The saving grace might be to have it do double duty as a structural element in the building, but many other posters have pointed out that there are many safety and construction problems that would have to be solved for that first.