On board Battery Charger

Wanted to get some opinions…I did a search but couldn’t find exactly what I am looking for.

I need to get an onboard battery charger. I need to be able to run of the shore power of my dock during the night. So I was thinking of mounting a changer next the batteries and just running a plug out of the cover and plugging in after a day of sitting on the water. Currently, I have two batteries separated by a Perko, with thoughts of adding a third in parallel to one of the 2 to be the “stereo” side of the switch.

I was thinking of this:

http://www.boatersworld.com/product/196901359.htm?bct=t13037503%3Bcielectrical-plumbing%3Bcibattery-systems%3Bcibattery-chargers

Or this:

http://www.boatersworld.com/product/196830426msk.htm?bct=t13037503%3Bcielectrical-plumbing%3Bcibattery-systems%3Bcibattery-chargers

I'm leaning towards the first one. I assume 20 amps will get me back at full overnight for 2-3 batteries? Does anyone have an experience with either or recommend something else? Thanks!

hey billthom
the last two years i have used a float charger called the battery tender. i can't remember the model #, but can check when i get home. it has a float on it so it will not over charge and it will charge 2+ batteries with a trickle charge. it is very small (maybe 4" x 5" 3"high) so pretty much unnoticeable when mounted and then you can just pull the cord out to the exterior to charge. worked real well for me and was easy... i want to say it was right aroung $100

I have the ProSport 20amp on my boat with 5 batteries. It works great.

second battery tender. you can buy one for each battery if charge time becomes an issue for the 2 stereo batts. or use one if you're not draining them that much. if they're regular 12 volt, one should charge them both overnite.

Look at BassPro Shop. Mine is the 5/5/5 Battery Tender. It's a float type. I have two of them charging 6 batteries for my system all seperated with a perko switch. They are made for charging deep cycle trolling motor bats but, when the green light comes on and says "Go Fish" your ready to crank the tunes. Cost $139 charges fully in about 2hrs.

Bass pro has the same style tender, available to charge 1, 2, or 3 batteries at the same time. Save yourself 100 bucks buy another battery spend the rest on Beer!!

Thanks, I'll check out the Battery Tender. I may need two as I don't know if 1.25 amps will be enough to take 2-3 batteries from emtpy to full overnight....

Often times in the summer we'll go out and sit for 7 hours draining both batteries and get up the next day and do it all over again.

do you have to worry about how your batteries are set up in order to charge them with a dual charger like the batter tender? isolator versus perko switch / series versus parallel?

or will it charge either way as long as you hook up both batteries to the charger correctly?

Hey tktige, you have a total of 6 batteries (1 starter and 5 stereo) off a Perko switch? Do you have an isolator? I want to do something similar without an isolator and was wondering how the stereo batteries gets wired: +to+ then -to- from one to the next? Do you also have an upgraded alternator? How many watts are your amps pushing? Finally how are the 2 chrgers wired into the 6 batteries? Thanks for the help. Sorry for all the questions

I'm using this...same as battery tender but a little bigger amperage. I've had mine for almost two years...worked great so far.

http://www.autopn.com/store/pc/viewPrd.asp?idcategory=212&idproduct=22358

Wakecat,

That's correct 6 bats, 1 to start the boat and 5 to run the stereo. No isolator. I use a 3 position Perko switch to seperate them. For the starting battery I just use the stock Alternator to charge it. For the other 5. I use two battery tenders to charge them. One has the capacity to charge 3 batteries at one time, the other charges the remaining two at the same time. I have 4amps rated at 3200 watts total, using wet deep cycle batteries. Wallyworlds best.
The 5/5/5 tender comes with 3+ and 3neg terminals all seperated with an inline fuse. The other tender is a 5/5 and has 2+ and 2 neg terminals. It's straight forward on the connections. When I bring the boat back to the dock, I just plug both into the 110 outlet and both banks are charged by morning. Easy to set up, you just need to check the water level in the batteries once in a while.



For the stereo bank you just connect + to + and neg to neg.

The battery tender is really not a charger, it is a charge maintainer. It won't fully charge ONE battery overnight. I have a Promariner 20 amp two bank charger on my boat, works like a champ and I'm ready to go the next day.

The one I have from Bass Pro is a Float Charger with the tender function built in. It fully charges all 3 batteries hooked up to it with no issues, stereo is kicking every time out. I have seen the small tenders about 3"x 2".

Thanks for the reply tktige. Thats what I needed to find out.