There are several companies that make sealed battery chargers to avoid corrosion issues. Coat all exposed connectors with CorrosionX. Here is my 24 volt thruster with seal batteries and sealed charger. Would work just as easily with a windlass. My charger runs happily off the modified sine wave inverter, so charging isn't dependent on shore power or generator.
Ted
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Blog:
mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by
The Pointer Sisters