There isn't much extra information about the actual test, as UL won't release it to the public. The only thing that is certain is that Batteroo had some test done at UL, under their supervision, with a genuine reference number.
The BatteRoohparvar brothers claim they spun their own DC to DC converter, but there is no evidence to back that up yet. They also did claim to have had to shrink components to make them fit on small AA/AAA PCBs, but again, tiny DC to DC converters and inductors have been available for some time, so that's probably all baloney.