The trouble with reports based on new experimental technologies is their tendency to omit any drawbacks and problems being faced, before they can be put into mass production.  And it can take efforts to read a bunch of sources to find some balanced versions.  Yet its possible.

Here's some comments from a more critical analysis of the graphene batteries for EVs.      Click Here   

<<  "A graphene battery uses a material called graphene in its electrodes. To step back further, graphene is a form of carbon. Graphene is a sheet of carbon that is only one atom thick. When stacked up, these sheets of graphene form graphite, which most people recognize as the stuff in pencils." 

<<  "Graphene Is Hard To Make And Work With:
Right now, graphene is extremely expensive and difficult to refine. While graphite is relatively easy to obtain on an industrial scale, it is hard to extract graphene from it. Laboratories have lifted layers of graphene off of graphite using adhesive tape, but that obviously wouldn’t work for cranking out enough of it to power the entire EV industry."  

<<  "A few other graphene-making processes have been developed, but none are ready for use in a factory. Furthermore, graphite is very delicate when spread thinly. (Imagine writing something in pencil and then trying to lift the lettering off of the page intact.) Graphene is literally as thin as graphite gets (since it’s one atom thick)."  

<<  "If Graphene Batteries Become Available, It Will Take A Long Time
Like solid-state batteries, graphene batteries sound perfect and almost miraculous on paper but are fiendishly hard to bring into reality. For one thing, physics always makes things harder when dealing with the brutal conditions outside the testing lab. For another, devising battery technology and mass-producing it are two completely different problems."

<<  "While scientists may successfully make one or two prototype batteries, one can’t simply scale up their method in the same way one would double the ingredients in a cookie recipe."   

<<  "At present, graphene shows a lot of promise. Whether it lives up to its own hype remains to be seen."     

And lets consider the common sense of evaluating drawbacks.   Recall how critics of adopting EV power for military tanks have pointed out the common sense argument that recharging of tanks on the battle field is virtually impossible.   

Seems there's a long road ahead before the drawbacks of graphene battery technology will be resolved, and become viable for its mass production.  Success is not assured.