Need help with a smell.

I boiled a battery a couple years ago. Nasty sulfur smell permeated everything in the camper. I also thought it was a black/gray water issue and I spent two days trying to solve the problem. I discovered the boiled out battery when attempted to raise camper with the jacks. No juice. The battery compartment was vented to the outside but there was no seal around the cables to the battery. I pulled the battery and scrubbed the compartment several times to stop any corrosion. The white cable had turned brown from the corrosive fumes. I sealed the hole around the battery cables but I decided to avoid a repeat by installing a deep-cycle AGM battery. No more issues. :)