Join Date: May 2007
Thanked 13 Times in 13 Posts
Rep Power: 9
Re: House Batterys
Free is a good price.
short story: my 31 footer's on her sixth season and the batteries were due for replacement. Manufacturer supplied her with a "dual purpose" (starter/deep cycle) group 27 12v starter battery and a 4d 12v deep cycle for the house. I was ready to simply replace with identical until I started studying on this site. There is much to be learned relatively easily by searching here...pay particularly close to anything Maine Sail has to say about batteries.
Knowledge gained here led me to a group 24 marine starting battery (NOT deep cycle and NOT maintenance free...just a basic lead acid battery). The group 24 is slightly smaller than the group 27 I had and is plenty for a battery that will only be there for starting and will be kept charged up at all times.
For the house bank, instead of the big 4D battery, in the same footprint you can fit two 6v golf cart batteries, and have the benefit of more amp hours than the 4D provides. They're also more "deep cycle" capable than 4D batteries that claim to be deep cycle. Just cable them together for 12 volts. Cables available at genuinedealz.com. I'll use the cart batteries to run the house (lights, anchor light, fridge). Will also use them for starting...the group 24 will really just be for emergency starting.
I got my batteries as Sam's Club....Duracell brand made by Eastern Penn...good batteries. $60 for the group 24 and $72 each for the cart batteries.
Your search will alert you to the fact that AGM and gel batteries have some requirements that make them impractical for many boaters, and very good for some....based on their chargers and alternator output, etc. With conventional lead acid batteries, the charging requirements are simpler and more forgiving.
If you don't care to do the golf cart batteries, and your needs are low...no fridge?....then you could get by fine with a 12volt Group 27 deep cycle lead acid battery for the house. Don't get a "no maintenance".
I'm just parroting what I've learned from others on this site, and while I don't know a lot about batteries, a month ago I knew NOTHING. Info on this site resulted in a battery setup that kicks butt for not a lot of money. The addition of the Victron battery monitor was icing on the cake, but that's another story. So my humble point is, if you're not real battery savvy right now, this site will get you there in a hurry.
If you want to get the job done and worry about getting further informed down the road, then you can't go wrong with what I've described, and any fine tuning or ?s you might have will get handled by the folks on Sailnet.