Use an acid neutralizer or you can use baking soda and water mix and spray the compartment down. If you have any electrical components (boards or such) avoid spraying them down. If you only have battery cables in there, then spray those down and the entire compartment. Let it set for a little bit and rinse with fresh tap water. just rinse with the hose. Just make sure that you have no electrical hooked up including any batteries. Let it all dry very well before you connect anything back up. The most important part is to not have any type of power anywhere when wet, & make sure it is completely dry before hooking up any power (i.e. batteries or shore).
2005 Damon Astoria 3679
300 Cummins ISB 5.9, Allison auto 5 speed
Life is to short not to have a good time and enjoy!!!