Yeah, the batteries in each of the 3 sets attach to Lex's mech on the arms and battle axe. http://kastorskorner.com/wp/lego-reveals-2018-dc-superheroes-sets/hyperfocal-0-5/
I'm a bit late to the party, so I'll keep this brief.
The builds look pretty good IMO, excluding the ice car, definitely some of the better ones in this line.
Figures look good, nothing great though. The hair piece choices on Cheetah and Frost look odd to say the least, but those can be easily swapped for better ones. Liking the prints (especially Frost, on whom I seem to be the minority. Never been a big fan on Reverse Flash so I may just brinklink her). I am disappointed that not a single figure this wave has leg printing yet alone molded boots. I understand they want to keep the costs down seeing as these are smaller sets, but still.