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Battery help

BulldogsCadillac

BulldogsCadillac

Just some guy
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Hi, I'm new to this forum and am just looking for a bit of help/opinions on what I should do for batteries. I ordered the dual battery setup from Bennington, and I am planning on putting in 3 sweet amps to run power to 2 REV8's, 6x xs-650's, and a 12" sub, possibly might add a couple more subs in the years to come. I have 3 amps, 2 Wet Sounds SYN4's, and a SYN1 for the sub. So I am looking at group 27 batteries because I would like to keep them nice like Gerry's setup, I'm ordering the same charger as it seems to be a winner, for batteries I see a lot if people like these Deka Intimidator batteries, I am looking at the 8a27m model, here is a special sheet

http://www.remybatte...?ProductId=2360

They are running $251 a piece here in Canada (I know they are a bit cheaper down south)

But I also saw these in my Canadian Tire flyer, their specs seem better, and I think they are the same as the Northstar battery, (I'm sure there aren't that many manufacturers of batteries so it probably is the same since the specs are identical. It is a Nautilus Pure Lead group 27 battery, here are the specs

http://www.canadiant...y.jsp?locale=en

They are running $299 right now. What are everyone's thoughts? Oh and I'm thinking AGM batteries just because my outboard only has a 50 amp alternator so the chance is greater that they will get discharged a little more than normal with the stereo going. Oh and before people complain about people being disrespectful with how loud their music is, I'm not that guy, but every once and a while, I like to let her buck!!! Thanks!
 
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Delphi, Exide and Johnson Controls Industries make pretty much all the batteries everyone supplies made to spec with their own name on it. Deka is made by East Penn and is also a great battery. I have one of their Group 31 AGM's in my boat lift and it weighs a ton!
 
There are tons of posts about batteries, please don't clutter up the forum with another battery question .... SEARCH is your friend ..... :D
 
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Sorry, I'm new to this. Oh, and the tons of posts about batteries, are almost all about hooking them up, NOT which batteries used, that's why I included spec links to the couple I am contemplating to get other people's opinion. I appreciate Tom's opinion, and the extra effort he knows he did. Too bad he doesn't have the tower and amps mounted or I would finally have some pictures of them. I don't know everything there is to know about wiring and electrical components, and I know some people on here do. So I'm hoping they take the time to look at the specs and give me their opinions as well. I think the idea of the AGM makes it the right choice, but it's a fair amount of money to dish out, so if people really think all I need are regular flooded Deep Cycle batteries, then I'm willing to listen. That's why I also included the amp models so they would know the kind of power draw. Thanks again Tom, anyone else have some opinions as well?
 
Wow, sounds like you took it personal ..... I WAS KIDDING !!!!
 
SEMPERFI8387 said:
Wow, sounds like you took it personal ..... I WAS KIDDING !!!!
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I know Dave, I was screwing with you. I just really hope people that know stuff about this take the time and chime in, as I really don't know what to do and need to get it figured out fairly quick. Plus I'll be honest, I'm a little disappointed that I've asked numerous people, numerous times if they could PLEASE do me the favor of snapping a few pics of speakers and amp placements and wiring on the tower units, and never gotten anywhere with it. Oh well. I know when you're asking a favor you can't EXPECT results, only hope for them. Sorry, guess I'm having a bad morning.
 
Ok, who kidnapped Derrick? And how much is the ransom?

We're gonna have to save him, the place just isn't the same without good ol Derrick!

Sorry for getting off topic there, i wish i had the answers for you Derrick, but i've only got the standard stereo.
 
His batteries will cost more than my whole stereo system :)
 
I have the wet sounds upgrade but not the tower model, if pic's of that will work I'd be happy to snap a few.
 
Wow, after the slap down the other day about people's posts this place has gotten rather boring. I for one would prefer to see everyone resume the normal fun...
 
Derrick,

Here are the pictures of my setup after all of the rewiring this morning. It's a little unique because of the Verado, but I now have automatic charging of both batteries without having to think about it. I changed from battery boxes to base frames with hold downs and squeezed both group 31's under there. I have the cuts on both of my hands to prove it. The "before" pictures are in my gallery for reference.

I'm still missing a couple of terminal boot covers that I need to run to the store for, but otherwise it's done.

Tom





 
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Derrick, why AGM batteries? I have been using combo starting/deep cycle marine wet cell flooded batteries for years, and as long as one does not run them all the way down, keeps them on a trickle charge off season and topped up with distilled water, in my experience they will last a long time (starting my 6th season and going strong in my bow rider). To my way of thinking AGM batteries are specialty 'purpose built' batteries, so what is the special need you are trying to fill with AGM batteries? As I understand AGM, the primary advantage is that they can be mounted in any orientation, and do not require topping off cells with distilled water. Charging voltages vary slightly from flooded batteries, and out-gassing of hydrogen may be less, but boat builder regs are not different between battery types from a minimum ventilation standpoint. I understand from go fast boater forums that AGM batteries rarely last three seasons (some speculate due to the pounding from the go fast boats, but there is great debate on this topic). From a pure performance perspective, there is little difference between AGM and wet cell batteries in applications appropriate to wet cell batteries, until you factor in cost that is. ;)
 
Hey Jim. My reasoning for the AGM pursuit is, I don't know any better. As I stated earlier, I have no idea about most of this, so I did what I do, read and research. From what I can understand, and everyone's thoughts, AGM is the way to go. The reasoning is simple, my alternator on my outboard puts of 50 amps, I believe the draw could be much higher. So with constantly draining faster than I'm charging I run the risk of dropping the batteries, or A battery, fairly low. I don't want to have to be constantly worried when out on the boat, so I figured AGM's are the way to go. The pure lead AGM also have a higher cold cranking amps, the regular deep cycle had 730 and the AGM was 1100 for group 27 batteries. I have also read quite a bit in audio forums where the people are getting between the 7-12 years out of them (most manufacturers state they should last between 8-12 years and even give 3-4 years full replacement warranty on them) keep in mind, from my limited knowledge, there seems to be 2 levels of AGM batteries, the ones I posted are 'Pure Lead'. There is quite a difference between regular dual purpose deep cycle flooded batteries and pure lead AGM, the specs show it. The major difference is how low they can be discharged without harming the battery. I unfortunately don't remember the link where I read it but I believe regular flooded deep cycle batteries are okay to discharge up to 50% whereas the pure lead AGM's can go as low as 80%. Plus they have a much faster recharge time, and can be cycled around double. I will be getting the same charger as Gerry, I have found a source in Canada, but as it sits now, this may all be a moot point. With all the extra costs and things I'll need to get, pretty sure I'll just have to take what my dealer puts in and hope for the best. I do have a booster pack, so I guess I'll just make sure it's charged and hopefully I can get through this season. Another nice thing is that pure lead AGM can hold a charge for 2 years with only 1-3% voltage drop. Not that it's a huge deal to hook up a trickle charger in the winter months, but it just shows their efficiency. Thanks for your response Jim, you were definitely one of the people I figured knew his stuff, and thanks Tom for the pics.
 
Derrick, glad to see you have been doing your research. It has been some time since I have looked at AGM/ flooded comparisons. I did a small bit of reading, and need to do more, but based on what I'm seeing, the 50A alternator and sizing of any shore power charging system is really the key here for your situation. And by your situation, I'm thinking of the monster stereo you have mentioned in other posts. What I'm getting is for given loads and sizes of the battery system, a small alternator / low usage rate (weekends opposed to all week) results in no advantage of AGM system costs over flooded technology. However, even moderately powerful charging systems and usage rates clearly benefit the cost effectiveness of AGM batteries. So, to your point an AGM battery can recharge considerably faster if you can feed it as many amps as it can accept, but a 10 - 20A charger may not realize this benefit. I do see where AGMs will provide more charge/discharge cycles, but for your specific concerns - relying on a house battery to supply an amp draw greater than the charging system can provide, for the money I'm thinking it's better to go bigger with one or more flooded deep cycle batteries in the house bank, than a smaller AGM battery even although AGMs are said to be able to discharge to 80% versus flooded 50%. Yes, recharge times will be longer, and space requirements larger, and perhaps costs similar, but time on the hook should be longer and lifetimes similar. The thing is that for all batteries, the greater the draw the less hours of capacity the battery can provide - it's not linear. A battery that can provide 200 minutes at 10A, may well only provide less than 20 minutes at 50A. For this reason, the rule of thumb is to figure out your typical draw and desired run time, then size the battery bank to provide four times that amount.

*edit - just read 4x for flooded, 3x for AGM.
 
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In terms of the longevity of AGM's, my experience with them in the last 4 boats I've had is they've lasted 6+ yrs, not 3, so it's a pretty good return on investment when you look at it that way. These were Optima Blue Tops, that were about $150-180 each at the time. I just put a strong charge on them at the end of the season with a proper multistep charger and in the spring they fire right up without a charge at all. My ski boats had dual battery setups and I never had a "fail to start" situation, even with my girls cranking the stereo. Of course YMMV.
 
TomS, yeah the slightly lower maintenance is attractive. Nice not having to top off cells with distilled water, and not having to trickle charge off-season due to the low self discharge rate (2 - 10% per month versus 8 - 40% per month for flooded). The optima blue tops are cool looking too.

Derrick, isn't your new boat coming with a brand new flooded battery? Wouldn't you only need to add a second bank of appropriate size rather than having to buy batteries for both banks if you stayed flooded? (It's not recommended to mix AGM and flooded).
 
Yes, definitely don't mix types. I just told my dealer I wanted mine with customer supplied batteries as the ones they use a not so good.
 
Mercury Marine recommends/require AGM batteries for the Verado. Don't know if that matters in terms of thus conversation but just FYI.

Tom, do you have details you can share on your auto charging system. I know my limits and all things electrical are definitely on my short list. Is this so something I can tackle or is it better left to my mechanic?
 
Manitowish1 said:
Mercury Marine recommends/require AGM batteries for the Verado. Don't know if that matters in terms of thus conversation but just FYI.

Tom, do you have details you can share on your auto charging system. I know my limits and all things electrical are definitely on my short list. Is this so something I can tackle or is it better left to my mechanic?
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It really depends on how they rigged your Verado as they're not all done the same. I ended up taking all the wiring out and re-doing it as I'm a perfectionist, but also a EE so it's in my comfort zone. Just adding a Blue Sea relay and switch (Add-A-Battery) is really easy though. Connect terminal A to the first battery, terminal B to the second battery with 4g battery cables and a small 16 gauge fused wire to ground, replace the old battery switch with the new one, and you're done. I'd say less than 2 hours for a good shop guy to make at all right, so figure $180-200 labor depending on their rates. I'd be glad to send a schematic of what I did via email.
 
Jim_R said:
TomS, yeah the slightly lower maintenance is attractive. Nice not having to top off cells with distilled water, and not having to trickle charge off-season due to the low self discharge rate (2 - 10% per month versus 8 - 40% per month for flooded). The optima blue tops are cool looking too.

Derrick, isn't your new boat coming with a brand new flooded battery? Wouldn't you only need to add a second bank of appropriate size rather than having to buy batteries for both banks if you stayed flooded? (It's not recommended to mix AGM and flooded).
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Actually the discharge must be less on pure lead versions than normal AGM if you read these fun facts on Northstar batteries

http://totalbattery.com/details.asp?id=898

As for what my dealer is supplying, I'm ultimately paying for it so I would just do like Tom and supply my own.
 
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