It seems to be very practical. The researchers made special effort to verify that, which is unusual. The silica nanoparticles are just fumed silica of a certain size, which costs <$1/lb. The final product can be added directly to the cathode slurry.

The growth process is the only remaining question, but it seems very tame. Methane is the carbon feedstock, and the furnace is only 1000 C. It doesnt have the pitfalls of normal graphene production because they arent concerned about monolayers etc- I would say their product has a lot more in common with expanded graphite than graphene. Because of that I expect its similar in cost to synthetic graphite, which is roughly equal to natural graphite.

So far there is no way to reliably mass produce graphene. There have been claims in the last year or so that we're getting closer, but nothing real yet.

instead of mass production let's have tiny production pods patent free so we can all make the graphene

So scotch tape and pencils?

Very low jab. There are other ways to generate graphene since, thank you.