It is right around the corner along with fusion and room temperature superconduction. 

It's probably ahead of those but you get my point. 

grayruby

I agree (as does the video creator). This has been a major technological bottleneck at least since I was in school and there have been numerous promising approaches that end up going nowhere.

Undisciplined

I have a friend whose expertise is battery technology and he agrees 

Bell_curve

tech

Why Solid State Batteries are Finally Here

I would be cautious with battery breakthroughs. I know little but I have a friend that works in the battery minerals industry and he likened it to the gold mining industry which he has also worked in. Everyone has a breakthrough, everyone just needs a bit more capital to hit pay dirt, almost everyone is full of crap. 

Not saying there is nothing here but I am cautious with all these "breakthroughs" people say we are close to until I see them in action. 