Best Batteries for the boat

[ezmobee]

Re: Best Batteries for the boat

There need not be any further negative comments made towards any poster inquiring about installing audio components in his/her boat.

Quality amplified systems can sound MUCH better at lower volume than some jerk playing his tunes from a low end head unit hooked up to some junky wakeboard tower speakers.

 

[CaptainKickback]

Re: Best Batteries for the boat

Theres really only two batteries to consider for you application if you want the best. Rolls or Optima. I prefer the Rolls for the heavy demands and Optima for quick recovery. Bear in mind that you not only need to consider RCA ratings but also time to recover. I'll use a trolling motor as an example. If you have the RCA's to run for 6 hours but it takes you 12 hours to recharge that doesn't leave you much time to get the boat on the charger and ready for the next day. Just something to think about.

Good point. Recharge time needs to be considered. OP , you have not said too much about how you wlll usr the boat. At anchor for how many hours? Use it successive days? Etc.

I had a cruiser with a Group 27 battery. It would only run the fridge, and part time stereo (no amps) for half to 2/3 of a day before I had to run the genny fir an hour or so.

I was recently partnered on a 35' Sea Ray where the house battery would run the same load all day. I was only in that partnership for about 5 weeks, so I never got around to noticing the battery size, but I assume it was a bigger battery.

It was nice to be able to go all day without running the generator. My recommendation is to get the biggest battery you can afford.

 

[bruceb58]

Re: Best Batteries for the boat

An Optima battery does not have near the capacity of a Trojan battery set up. A T105 Trojan battery setup will have 225 AH with a 20@ draw using 2 105s in series. Please let me know what group of Optimas will meet that spec. Recharge time is determined by the amount of current drawn from the battery. The actual brand of battery doesn't matter. If you have a big enough charger, it will be ready for the next day. Trust me, golf carts charge just fine overnight and they use mainly trojan batteries.

Trojans are easy to find and relatively reasonably priced since they are used for golf carts and RV industry. Not sure about the Rolls although they are good batteries.

 

[kylejb2663]

Re: Best Batteries for the boat

Thanks to everyone to has responded on this thread and for the feed back!!!

Yes, I do want a solid quality audio system, not so much to play loud but a sound system that sounds good at lower volumes and if I want to turn it up a little bit, I can. I don't think when I am moored out in the middle of the river that anyone would be able to hear me to begin with. I am very respectful of other boaters and would never turn it to MAX volume while around other people or even by myself lol!

I am planning on using the boat as a cruiser- I would like to anchor out with my friends, swim a little, maybe have some sandwiches, listen to music. My Fiance is all about the sun pads that we are designing for the boat so she can lay out on the bow deck and relax. If we want to spend a night, I would like to be able too, probably not more then one night out though. I may be purchasing a 9,000 BTU A/C unit from a friend, he is replacing it because the heat does not work but the A/C works perfect. So he said if I threw him 150 bucks for it I could have it. This would be nice because the boat can get warm in the summer down there so for sleeping it would be awesome. It certainly beats spending 1200-1400 dollars for an A/C Unit, However, this opens a whole new territory on whether or not I can run the A/C while moored without a generator. I certainly don't want to spend the 5,000 for one, I would rather sell this boat and go buy another that has A/C and a Genset already.

I did see the A/C unit that Captainkick is talking about and that's what gave me the idea of running it on a battery. But, I think 9,000 BTU it a lot to run off the battery.

The battery charger I have is old so it needs to be replaced, I was thinking of a Xantrex or Promariner charger. For batteries, it seems to be Trojans everyone has had good luck with.

What do you guys think I should do?

 

[kylejb2663]

Re: Best Batteries for the boat

Also I should add that I always thought that Optima's were the way to go- But from what it seems in spec wise they are not coming close to Trojan's... Interesting?

Also, how are the rolls batteries?

 

[kahuna123]

Re: Best Batteries for the boat

Agreed, there is no gen involved so that's a mute point. Some how some way golf carts charge all night and run all day, amazing.

Dang, all that college for nothing. I would just run number 18 to those speakers. They will be fine.

Dang, another wasted semester. So lets back WAY UP. It takes current through the coils of a speaker to MOVE the magnet to push the cone to push air to make sound. The current only forces the speaker cone one way. SO what happens when the cone tries to return to where it was. MAGIC, the magnet moves past coils and creates current. IF there is resistance to the return current it will slow the return down. So the next cycle the cone has not had a chance to return to "neutral". Therefore NOT being able to push as much air.

 

[bruceb58]

Re: Best Batteries for the boat

Hate to tell you this but speaker cones move in both directions. If they didn't, you wouldn't have true sound and have massive harmonic distortion. Not sure who your college professors were that taught electronics but maybe they should give you a refund

I haven't heard so much mis information since I was at an auto stereo store talking to one of the sales/install guys.

Bottom line, his stereo system basically has no impact on what batteries he needs so not sure why its even in the discussion to be honest. Its not his heavy hitter.

 

[bruceb58]

Re: Best Batteries for the boat

Also, how are the rolls batteries?

They are in the same class as the Trojans. If you take a look at solar sites, Rolls and Trojans are mentioned in the same breath. Trojans will be easier to find in my opinion.

 

[fishrdan]

Re: Best Batteries for the boat

Dang, another wasted semester. So lets back WAY UP. It takes current through the coils of a speaker to MOVE the magnet to push the cone to push air to make sound. The current only forces the speaker cone one way. SO what happens when the cone tries to return to where it was. MAGIC, the magnet moves past coils and creates current. IF there is resistance to the return current it will slow the return down. So the next cycle the cone has not had a chance to return to "neutral". Therefore NOT being able to push as much air.

Whaaat???

A speaker runs off of AC (alternating current). Half of the AC wave pushes the cone out and the other half of the AC wave pulls the cone back in. If the speaker cone's movement wasn't controlled both in and out, the sound would be horrid, if it produced any sound at all. The cone would most likely just be floating on top of the half waves, if the cone was only forced in one direction.

 

[kylejb2663]

Re: Best Batteries for the boat

They are in the same class as the Trojans. If you take a look at solar sites, Rolls and Trojans are mentioned in the same breath. Trojans will be easier to find in my opinion.

Got ya- I'll start looking into Trojans and see what I can fit. Any models that you would recommend? At this point I think running the air may not be feasible unless I got that model that runs on only 4 amps and ran a battery dedicated to that and only that...

 

[bruceb58]

Re: Best Batteries for the boat

Start with the T105 and go from there. They are the most common. Depends on what your draw is going to be. Also, size it so you never draw a battery down below its 50% capacity point if you want them to last a long time. Occasional draw below 50% is ok. If you draw down more than that consistently, it will lower the capacity of the battery.

 

[kylejb2663]

Re: Best Batteries for the boat

Start with the T105 and go from there. They are the most common. Depends on what your draw is going to be. Also, size it so you never draw a battery down below its 50% capacity point if you want them to last a long time. Occasional draw below 50% is ok. If you draw down more than that consistently, it will lower the capacity of the battery.

\\

Bruce, this may sound a little novice of me but how exactly do I calculate the AMP ratings and what load I should be going with. For example if a battery has a reserve time of 120 minutes at 75 amps what exactly does that mean... Does that mean that if you have 75 amps coming out of the battery it would last 120 minutes?? Sorry I'm new to this battery stuff!!

 

[bruceb58]

Re: Best Batteries for the boat

Yes. Just be sure when you compare specs that you compare apples to apples. Many specs are written with a 20A discharge. The AH capacity will be more with a 20A vs 75A discharge spec. Do a google search on Peukert Constant.

 

[fucawi]

Re: Best Batteries for the boat

I am supprised Bubba has not recomended his famous lead acid batteries with the solid lead plates ..if you can find any buy buy buy these are very very very rare ..comparible to rocking horse shonet...

 

[oops!]

Re: Best Batteries for the boat

hi all.....im not really a electronics guy....but i am learning.

i just went thru this.....(the thread and the problem !)

i would seriously consider the suggestion of going to multiple 6v and hooking them up in series..

here is why.......you are overnighting.....

that means stereo day.....ac all day..(btw,,,,the ac is 110v with a 12v pump)...fridge..... and the ships systems.....im thinking fresh water at least. this will all run all night.
now.... in the morning we will have coffee ! that means coffee maker and the music gets turned back up,,,,with the fridge and ac still running....

count the amps !!!!!!!

4 6v in series and inverter or your dead in the water by midnight on 2 12 v

 

[kylejb2663]

Re: Best Batteries for the boat

The Trojan T105s are 6 volts correct? Are those the types I would want to use and how would I hook these up to a battery charger? Do I need a specific battery charger for 6 volt batteries?


Thanks guys!!!!

 

[bruceb58]

Re: Best Batteries for the boat

Yes, like Ooops posted, you hook them up in series. Then you just get a 12V charger that connects from the negative of the lower to the positive of the upper. I would get a 20A charger at the minimum. You can get a Dual 10A charger like the Guest 2620A and parallel its outputs to form 20A. I would also highly recommend getting an ACR(Automatic charge relay) installed between this bank and the engine battery so you can charge while the engine is running.

 

[kylejb2663]

Re: Best Batteries for the boat

Sorry guys! I'm going to sit down later tonight and calculate the amps!! Wedding plans have been taking away from the boat a little bit.... LOL

I have a plan not sure if it would work or if it's overkill but I'll put it together tonight and see what you guys think.

 

[sschefer]

Re: Best Batteries for the boat

Regarding the Optima's yes, that is correct, the Optimas don't have any where near the stamina of the Rolls or Trojans but they recover very quickly. They're not bad but ask any hot rodder with a killer stereo if he's running Optima's and the answer will likely be NO. If you're running an onboard charger like the ProMariner you might be better off with the Optimas because running a set of Rolls or Trojan's down to 60% and then trying to recover them on a 20 amp ProMariner charger would be about a 10-12 hour charge. That's just a rough estimate from my experience with a ProMariner tripple battery charger.

I guess the point I'm trying to make is that there comes a point where too much is not as good as good enough.

Often heard scenario --- "Hey joe turn up the radio"... "Can't man, forgot to plug the charger in last night"..

Just food for thought, I'm sure you've got good advice about the choice you should make and you'll make the right one.

 

[bruceb58]

Re: Best Batteries for the boat

Another reason you don't want" Optimas is that you then have to put a bunch of them in parallel since they are 12V. If one cell goes bad, it brings down a good battery that is in parallel with it. The statement about bringing the Trojans down to 60% is true of course since they are larger capacity batteries. The Optimas have a lower capacity so of course they will take less to bring up.