I have my batteries and now solar panel. Will be doing a four night test with the Intellipap backup (waiting on the batteries to hit about 6-8 weeks from charge to simulate a more realistic real-world charge condition) Also want to do the recharge via the solar panel. Have panel in hand but have not yet built the angle-adjustable frame yet (have figured an different angle at my latitude for each season - not perfect, but still better than a single, fixed angle frame. Want to use neighbor's drill press rather than free-handing a drill on the pvc I intend to make the frame from. Neighbor left on vacation early this week so will have to wait on him to return to get this put together.
Should safely get almost 4 nights from the battery and a charge current of 8 amps from the panel (at ideal conditions - which will never happen) I figure at least 8 hours under good conditions (since there are occasional clouds and I will not have an active tracking mechanism so the angle will be pretty good, but still always sub-prime), probably will get full recharge in most cases over two days.
Will report back when all is accomplished.
I never used a inverter with a cpap machine but have used an inverter to power a lot of other things. My inverter is only 300 watt and is several years old. It works fine and is reliable.