This is such a simple and basic idea that often goes overlooked.
Some time back I had a coach with an inverter and the new (maybe a couple of months old) battery had to be replaced. The post was melted!
As usual, the cause for heat was a weak connection.
The customer simply didn’t sufficiently tighten the terminals down. The inverter drew a lot of power and it was more than the weak connection could handle.
Last week I has a coach with wing nut terminals. I don’t like them because it gives the impression that finger tight is sufficient. It’s not. ALWAYS use pliers to add extra torque to wing nut battery posts.
Also, clean all terminals and replace as needed if badly corroded.
And lastly, always use a spray terminal protector. This will prevent corrosion.
Numerous problems are caused by simple negligence, and the prevention is quite easy.