I've watched Baron talk about TSLA on CNBC. He's pretty much a shill for the company, IMO. That isn't to say TSLA's battery business won't grow, but it is to say that I don't think Baron sees TSLA objectively. He has a lot at stake with the company so naturally he's going to talk it up.
Right now TSLA uses a loophole in accounting standards, specifically ASC 280: Segment Reporting, to avoid showing how that segment of TSLA's business is doing. I wrote an article on this, two actually, on Seeking Alpha. Look for "Bryce in TX" and look at the profile there if you are interested in researching this. If TSLA were actually making money in this segment they'd be reporting operating income by segment, listing assets by segment, and reporting other expenses by segment. The fact they aren't tells you they are losing money on this segment. That may change over time, but that's where they are at present.
I think TSLA has reached critical mass and will continue to survive but they face some serious challenges in the short term. The acquisition of SCTY is one of those challenges.