>Energy-wise, we’re talking about 1.36 milliwatt-hours per cm3, about twice the density of activated carbon, and comparable to a high-power lithium-ion battery.
That's not really comparable to any "high-power lithium-ion battery" at all - Wikipedia quotes 250–730 Wh per litre for Li-ion (so 250-730 mWh/cm^3), and a quick calculation with a laptop battery I have on hand agrees - 84 Wh stated in 27x4x2cm = 388 mWh/cm^3.
That's not really comparable to any "high-power lithium-ion battery" at all - Wikipedia quotes 250–730 Wh per litre for Li-ion (so 250-730 mWh/cm^3), and a quick calculation with a laptop battery I have on hand agrees - 84 Wh stated in 27x4x2cm = 388 mWh/cm^3.