I started hanging mine in my hull so they don't end up in the skanky water in there.  It also occurred to me to wrap a plastic bag around them and rubber band it - with a little dessicant packet inside, but that was too much work!

Good luck~   

Not exactly sure where your corrosion is. I attach waterproof connectors (link below) to my battery so I can easily remove and charge it. To connect them to the battery I attach them to the slide on connectors that slide onto the battery terminals. I then cover the battery terminals with silicone caulking to keep water out. I also put some dielectric grease on the plug connectors. In my yak I keep the connectors off the bottom so they never sit in water.


https://smile.amazon.com/YETOR-Waterproof-Connectors-Connector-Extension/dp/B07WDBLFDN?ref_=ast_sto_dp&th=1&psc=1

I'm using SAE connectors (sidewall port and extension cables).  The ends have caps that I close when the kayak is off the water, I've squirted dielectic grease into that space, and I use a can of air on the ends to clear out water before I store the kayak. 

It took a bit of splicing, but 14 gauge wire is fat and easy to work with.

There's still some corrosion (a bit of green on the side port), but the system is performing well after at least 12 months.