Originally Posted by jrophoff
This is what I have. Unlike a float charger it is capable of bulk charging too. Since it charges at a slower rate, the battery stays cool, ultimately prolonging my batteries life:
Battery Tender® Junior 12V @ 0.75A - Batterytender.com
It does a good job, and since the only thing that I run off the battery is my depth finder and running lights (cabin lights are LED and use their own batteries), I don't use too much battery. Especially since all my sailing is done in the day time. After a long day of sailing I am down to 90-95%. Now that I have a new motor that charges the battery as well I should be in good standing.
I am adding a stereo this year. That may push me into purchasing a larger battery charger.
A three stage battery charger is the best way to charge your batteries. Also dont forget if you have wet cells to equalize every month or so to desulfate the lead plates.