Deep Cycle Batteries
 

I've got dual batteries in my boat right now (group 24 unknown brand) and I would like to know what batteries will last the longest for running the stereo. I upgraded to 2 Rockford Fosgate amps and I'd like to run the stereo for as long as possible on one battery and then use the other for starting the motor. I've heard that the Optima batteries are good, but they are $175.00 each. I could go up to group 27 batteries but then I would have to get new battery hold downs. Any ideas?

I run Optima red tops in my 272. I have a 400 watt Kenwood. So far so good,,, I got them locally for $105 a piece.

Exide makes a battery called the Orbital that uses spiral technology for vibration resistance. They work as well or better and cost less than an Optima. I can send you batteries for $91.10 each plus freight.

Optimas and other spiral cell batteries (using AGM technology) will "last" for more cycles and will tolerate rapid charging better than any other readily available affordable battery technology.

What they DONT do is they don't offer as much punch per pound as a good old "regular" deep cycle battery. They offer incredible charge/discharge amperage rates, which makes them great for starter batteries cause you can get immense CCA's out of a tiny battery, but they do not offer extended power capacity in relation to TIME, as you would want in a hotrod stereo application.

A regular deep cycle Group 24 is 80 amp-hrs. at 50 pounds.
A regular deep cycle Group 27 is 90 amp-hrs. at 62 pounds.
A regular deep cycle group 30/31 is 108 amp-hrs at 72 pounds.

Any of the Optima or other spiral cell battery is around 55 pounds and 75 amp-hrs (but they have kickin' CCA numbers..).

If you are concerned with overall weight, you can use a smallish starting battery and a larger deep-cycle or "house" battery.

You'll get lots of recommendations, and I will not try to argue which battery is the "most superior".

Here's my recommendation:
Go to AutoZone and get a "Gold" 3-yr free replacement Group 24 battery to use as your starter battery. Tell them it is for your custom truck (give them the year and model to activate the warranty). Get another "Gold" 3-yr free replacement Group 27 or 30 battery to use as your "house" battery. It, of course, is for your other custom truck.

These batteries have 3-yr FREE replacement and a zillion months of pro-rated warranty.

Will they last as long as an Optima? Who cares? If they last 4 years, it will cost you around $17 each to replace them...

I've actually used gel batteries in boats, and AGM batteries in jetskis. I've had mixed luck with esoteric high dollar batteries. AGM's and gels both require tweaking of your voltage regulators to charge them properly.

Right now, I own 13 Auto Zone Gold batteries. The newest is 2 yrs old. The oldest is 5. Good batteries. No failures yet. If all of my boat batteries end up tapped out this spring, I could care less - I'll just make a run to the Zone and get them replaced for next to nothing.

I've heard good things also on the Auto-Zone Gold batteries from previous threads, and I do need to replace my batteries this season and think I may try a pair of those......Fred

Thanks for the input. Is there a problem charging two different size batteries with the battery switch in the both position? I have heard that the batteries had to be the same sizes and type (deep cycle or starting) if you are charging them or using both.

You'd be far better served by using a battery isolator designed for a single alternator/double battery setup for charging, but in lieu of that, the BOTH switch will work fine for topping the batteries off.

Here's the catch: If one battery is nearly dead, and the other (starting batt) is hot and charged, then you need to start the boat on the hot battery and then switch to the low battery to let it charge. That way, the alternator will charge the battery at a normal rate (35 to 75 amps) instead of the battery being hit at 600 amps from the hot battery which is bad for both of them. This is the case regardless of whether the batteries are the same or different size and style.

Also, be sure to use a battery switch that goes OFF-A-BOTH-B so you never cross an open post while running the motor and swapping fro one batt to the other, else you can pop a diode (or triac) in the regulator.

mcollinstn - I thought regular car batteries were not made to take the bouncing that occurs in boats, I thought that was the whole purpose for a marine battery was that they can take the bouncing around. You say that you have had good luck using a car battery in a boat? They will last a whole season? I did not know that. You learn something new every day.

I do have a question for you, with dual batteries, hooked up, to a battery switch, I am wanting to place a trickle charge on each battery, I will do one battery overnight and then do the other battery the next night. Do I need to disconnect the batteries from the boat or can I just leave them hooked up with the switch turned to the off position? Dumb question, I know, but to me a dumb question is one that is never asked.

mcollinstn - one more question. Here is the way my battery switch is set up

2 off 1
both

I am using one cranking battery which is on switch 1 and one deep cycle battery on switch 2. If I start the boat with the cranking and then while the boat is running with the radio on can I safely switch to the deep cycle without damaging anything? Or can I start the boat on the both switch and switch to the deep cycle (switch 2) without damaging anything? Or vice-versa.

As long as you swing the switch thru the BOTH position when swapping batteries with the motor running, you are fine. The trouble is when you swing it thru the OFF position when swapping batteries with the motor running. Do you understand the difference?

I've only destroyed 2 batteries from pounding and vibration. They were both in a 16' long 95 mph outboard padvee. I broke the stringers out of that boat with the pounding and I don't know if any battery would have done any better. The two batteries I shook apart were both Sears Die Hard Marine Deep Cycle batteries. AGM/Optima style batteries are the MOST "shakeproof" out there but buying one for that reason alone in a pleasureboat is misguided.

You should turn your battery switch to OFF when you store your boat. I'd also recommend that you buy an automatic 10-amp charger since a trickle charger is best used for maintaining abattery, not charging it.

I ended up using the Optima Blue top Deep cycle batteries in my boat and I have the AutoZone Gold’s X 2 in my truck. The reason for my choices were simple, my plastic Gill battery hold-downs that the boat came with were JUNK. I had to change them and found the battery boxes made by Eddie Marine for the Optima’s. I could not believe how nice these boxes are they are perfect in every way including price (very reasonable for what they are). I see that they now have them for regular batteries.
My choice was strictly cosmetic and the fact there is zero maintenance till they die. I have run them 1 season and have seen no change over the regular batteries. The only logical difference I can think of is the regular battery will have some fluid (electrolyte) sloshing around and may (depending on plate support design) have some premature plate abuse. I would also add that some better marine batteries should have a deeper sediment chamber allowing for longer battery life.
With that said is it worth the extra money because you are going to have a battery last 1 or 2 years longer ?? I would have to say if you plan on saving money and want reliable power buy a load tester and as soon as you see them starting to get week replace them like mcollinstn told you. His thought on the gold top warranty is the best advise that I have read about battery questions. You can replace them every few years for very little money. And you now have a choice of cool battery boxes in both Optima style and regular group batteries.
I should never get in front of the keyboard while I'm doing my morning coffee :crazy:

Please excuse the wild splater paint it looks much better with motors installed:rolleyes:

mcollonstn - I just have a trickle charger and was thinking of moving into a 10 amp charger for the reason you just said. What is a good, economical brand to buy that does a good job without getting too pricey? I imagine battery chargers are like everything else, you get what you pay for. Thanks for your advice, you seem pretty knowledgable. Eric

mcollinstn - I looked at a charger after work at Sears, they have one that has a 5 amp setting to slow charge and a 15 amp setting to quick charge, there are also three settings for the type of battery you have, typical car battery - setting 1, deep cycle battery - setting 2 and deep cycle that has a green fish eye on top - setting 3. It also has a starting setting for starting a dead battery, its on sale for $75 bucks and it has an automatic shut off when the battery is fully charged, also a meter showing how much of the battery is charged. What do you think? I know you said 10 amp charger, will 15 amps be too much? I'm thinking about getting this one because you can use it on virtually any type of 12 volt battery, for my lawn equip, 4 wheeler, car and most important boat. What are your thoughts? Thanks in advance for your help. Eric

bigE

That's a good one. Keep it well-ventilated while it's being used, and keep it from getting rained on and it will last a long time.

While were on this topic, I was definaltly considering to OPTIMA blue top - strickly as power for my stereo - my question is does it outlast conventional deep cycle?? - it I can get an extra hour w/music than it's worth it to me - do they fit in regular battery box?? & whats a good price for the blue top optima??

My freinds, switch to 6 volts golf cart batteries :

NOTHING beats those. 2 x 6 volts in serial, shure a lot of pounds but a lot of SOUND and for LONNNNNNNNNNNNNNNG periods.

A friend runs 1 000 watts amp all day and starts is 454 like a peace of cake!

Ran-dom

Outlast?
What are you asking?
What are you comparing it against.

Can you run a 20 amp load longer on a blue-top Optima versus a std deep-cycle Group 24? They are close, but no, the std will run a little longer, and if you are comparing against a Group 27, the conventional will run longer still.

Can you charge/discharge/charge/discharge/charge/discharge a blue-top Optima more times than you can a conventional deep-cycle? Yes.

If you perform poor battery maintenance and let the battery sit in a discharged state often and do not keep it away from sub-freezing temeratures will take more months/years to go belly-up than a conventional deep-cycle? No. Poor maintenance can trash any battery prematurely, although the Optima will be more resistant to dry-plate accelerated sulfation.

JS232,

Power longevity is in direct relation to weight. Two 6v golf cart batteries at 66 pounds each result in 235 amp-hrs of battery power. One 8D 12v is 132 pounds and 224 amp-hrs.
Two Group 31 12v batteries yield 240 amp-hrs at 66 pounds each.

No magic here.

Now, in some areas, "remanufactured" golf cart batteries are very affordable. This could be a consideration.

Another point to remember is that properly-maintained batteries usually die "one cell at a time". A 12 v battery contains six 2 volt cells. One lame or shorted cell spells battery replacement. A 6 v battery contains three 2 volt cells. A lame cell means only replacing "half" of a 12 volt battery.

Regardless of one's theory on the issue, it is hard to compete money-for-money with a $65 AutoZone 3yr Free/84month prorated battery.

Unless you truly feel you need a high-tech sealed submersible mat-wrapped spaceship battery, your probably spending money simply for looks or prestige when going AGM/gel/Optima.

But, hey, there's nothing wrong with that either. Just make sure you know what any why you are choosing...

"Unless you truly feel you need a high-tech sealed submersible mat-wrapped spaceship battery, your probably spending money simply for looks or prestige when going AGM/gel/Optima."


Hey didn't I just say that :D :p


Good advise mcollinstn :)

I always run my switch in BOTH,, anyone see a problem with that?

I would run optima blue tops, watch ebae youll find them for 100-125 each

No problem with always running in BOTH. Some guys like to swap to one battery while rafting to avoid being dead in the water when the batts are too drained to start a motor.

Just don't swap to BOTH with one hot battery and one dead battery. It's hard on both of them and can, every now and then, result in blowing the top off the dead battery (never ever a pretty sight).