Graphene vs Lithium in the future, page-6

That article is from 2015 so it would be worth checking out more recent information. My view is that it's something to keep an eye on but the production cost and technology is no where near mass market ready. All the graphene batteries I've seen required the graphene to be in a suitable structure such as sheets with fairly low imperfection rates which is not something currently achieved on any significant scale. If you consider the time frame it would take to change over battery production and build supply it would likely take years and even if a viable production process is established it won't be ready for the initial wave of EV vehicles so I imagine there will be solid lithium battery demand until at least late this decade. Whether that translates to decent profits for miners and producers is yet to be seen.