As for no battery, it's a good thing as it would be even larger and much more heavy.   As an owner of one, it already weighs 71 pounds and adding a battery to run that thing would triple it.   I rather have the base and get a separate battery pack which I already own.  My family loves it and we can't wait to get warm enough to have movie nights in the backyard.   To me not having its own battery is a plus as it make it larger if you still want the base and with or without the base it will be much more heavier.