marine battery

[gert]

My 12v wet deep cycle battery is currently being stored in my shop; I occasionaly trickle charge it. It "sweats" around the + terminal and grows moist corosion on the terminal. It's water level seems fine.

What is going on?

[Michael D. Storey]

There is a salt present, which is hydroscopic, which is why that bag of white rocks in your trunk turns hard, then mucky then falls through the hole it rusts in the floor. Suggest you clean off sed terminal with a wet rag, etc. Do not use same to blow nose. Discard reverently.

[waynec]

There is a salt present, which is hydroscopic, which is why that bag of white rocks in your trunk turns hard, then mucky then falls through the hole it rusts in the floor. Suggest you clean off said terminal with a wet rag, etc. Do not use same to blow nose. Discard reverently.
During your trickle charging a fine mist of acid is escaping the vents ..., and then it's attracted to the positive terminal. Clean, then grease both terminals to seal them from the surrounding atmosphere. Axle grease or even Vaseline will do the trick. Any auto parts store will carry special battery terminal anti-corrosive pads (red & green rings - you've seen them on car batteries), if you want to take it to the next level.

Do a little research on the battery maker's web pages for other tips on storing a battery.