will i need a combiner box or can panels safely be paralleled without one?

[SunEagle]

the only other option i can think of is to buy several inverters capable of running at different voltages, one for the 3 batteries in series at 36v, one for 24v for in case 1 battery fails, and 1 for 12v for if 2 batteries fail. If i am using 1/0 cable between the batteries that seems like it would allow the system to function properly, but then again i am new to the world of solar.

You may find a 36v inverter but those are usually hard to come by. Most available are rated 12v, 24v & 48volt.

If you are building a large battery system it is always better to make it out of low voltage (2v, 4v or 6v) high Ah batteries wired in series to create a single system at 12v, 24v or 48v.

But as your concern, if you lose one of those you lose the entire string. Based on history if one of those go the rest will go anyway but that is always a gamble.