Best battery to run LED's off while parked
 

I currently have my boat set up where i have two Interstate 24m-xhd batteries on a Perko with 1,2 and all postion. I run all my stereo off the the Kinetik 2400's which have their own On/Off switch. The LED's are tied into the Interstates.

Issue: When parked for about 1:30 to 2 hours I will kill battery 1 with all the LED's on...the lights are obviously still on but I am not able to crank. For those who havent seen my boat i have a whole ton. This hasnt been much of an issue b/c when im ready to leave i switch over to battery 2 and it cranks right up. The LED's will also dim a little bit once the voltage drops down.

What I have tried: I slapped in a brand new Optima blue top D34M in the battery 1 postion today. Once installed I left the LED's on for 4:30 hours and it would still have just enough juice to turn over. After just over 5+ hours the boat wouldnt turn over. The Optima only had around 12.3 volts in it when i started this. This is a huge improvement and i can live with this.

To me it looks like the Interstate has crapped out on me. The difference in Ah cant be that far apart in both of those batteries...i believe the Optima is either55 or 75Ah, not sure on the Interstate.

Solution: What batteries would be the right choice for leaving LOTS of LED's on for a long time without dimming and still be able to crank up just in case of emergency?

Since the Interstate is one of your starting batteries, how is it getting recharged after being depleted by the LEDs? How old is the battery?

The D34M will do a better job then the Interstate cranking with continuous loads such as the LEDs, but does not have near the Ah's as the Interstate Marine Deep-cycle. A deep cycle will be the best choice and will work fine as a backup starting battery. I would run a primary starting on one side of the switch and then a deep-cycle for the LEDs on the other side of the switch. If you dont already, I would implement a means of recharging the LED battery when the boat is not in use, and not rely on the alternator to replenish it after a deep discharge.

The solution is any deep cycle battery that has the most amp/hours. There is nothing unique about the draw of LEDs. The Optima group 34 deep cycle Blue Top has 55 amp/hour capacity. A Deka SeaMate group 24 AGM (same basic footprint as a 34 but taller and heavier) will cost about the same and provide 44 percent more capacity at 79 amp/hours. A basic Interstate wet deep cycle group 29 will have as much reserve time as the Deka at 2/3 of the cost and fits in a group 27 case, so not too much larger.
Even a deep cycle battery has less tolerance for a really deep discharge. The number of cycles you get before noticable degradation will be significantly reduced as compared to a far higher quantity of shallower cycles. So additional capacity will result in shallower cycles and much longer battery life.
But then you need to have a good AC shore charger as you really can't depend on your alternator (even with an upgrade) for restoration...given the size of stereo and other loads that are competing for current.

David
Earmark Marine

What are you charging your kinetics with?

If it were me, I'd add an additional battery. You could charge the 2 kinetics in paralell and the optima blue top off of 1 Prosport 20 charger, and then your starting and back up battery off another prosport 20 charger.

I'm assuming you already have 1 on board charger? Otherwise you would probably want to get a 4 bank charger.

I would have thought with your stereo, fogger, leds, etc you would have had more batteries than what you do.

With several Kinetik 2400s plus the other batteries I would definitely step up to a much larger triple bank charger than a ProSport 20. We sell alot of the 20s and I like them but the charger investment needs to be more in line with the rest of the system. If you don't already have one look into a large Dual Pro, Intelli-Power, Xantrex or ProMariner ProTech series.

David
Earmark Marine

For the record im running three Kinetik 2400's and two Interestate 24m-xhd with a ProSport 20 Plus. Ive contemplated throwing another charger in it but honestly I've haven not gone out two days in a row where I kill all the batteries. I usually hang out and plug into shore power within a few hours. Now with the noise ordinance in place of Lake Austin the only time I will really get use the stereo and other accessories to its potential will on Lake Travis once in a while.

David - from what your telling me it sounds like a Deka SeaMate group 24 AGM and Interstate wet deep cycle group 29 are pretty much the same across the board expect for the price?

Do you recomend me doing the Interstate?

The interstate group 29 (srm-29) has a lot more ah capacity than the deka mentioned. It's more like 115 ah.

Should I swap both of the 24m-xhd's out for the SRM-29? I noticed the group 29 has quite a less cranking amps.

Brian,
Sorry, but I have to make a correction in what I wrote above. An Interstate wet deep cycle group 29 (virtually the same size as a 31) will actually have a similar reserve capacity as a group 31 AGM like the Deka at about half the price. So if you are looking purely for the most amp/hour capacity for the buck, its generally hard to beat a wet battery. There are numerous other advantages to an AGM which is why you invested more in the Kinetiks. So I'm not really recommending one over the other. I like to use AGMs unless I get a sense that the boat owner isn't going to be very disciplined about charger-related battery care and then I steer towards a wet battery. AGMs really could use good quality shore charging beyond the alternator in deep cycle applications to maximize their performance and longevity plus if someone isn't caring for the batteries an AGM initial cost and replacement cost will add up fast.

David
Earmark Marine

With a small block in warm conditions we see many boat dealers loading new boats with nothing but deep cycle batteries rather than cranking batteries. Battery functions like "cranking" aren't linear so I couldn't tell you if a battery with a higher cranking capacity still has an advantage in a partially depleted state. If you are using the battery in a dual purpose role like running LEDs and starting also then you might ask more of a battery expert like Brett. But I would guess that with a larger group size you would be fine with a deep cycle. Also, if you have daul batteries and a switch on the non-stereo side, I like two identical and large deep cycles so that you can alternate their usage every other weekend and extend the life of both.

David
Earmark Marine

the dual interstates have a perko on them and the kinetiks have their own switch which are completely independent from the interstates. I may try the Inter Group 29's out. Can anyone explain the adv/disadvantages over wet vs. agm for this application.

Brian why don't you swap the 24's for the 29's and throw a prosport 20 dual bank on them. You said you get them cheap seems like money well spent to me.

BTW the 29's will be about 2-1/2" longer than the 24's, something to keep in mind.

I don't think an agm has an advantage in this situation as long as you have the space to mount them upright. If you look at the investment you will have to make the 29's are the clear winner. Changing out to those are like putting 4 optimas in there.

awesome - will it looks im headed to go pick up the SRM-29's.

The 29's are $170 at the local dealer - not to bad. When i spoke with ProMariner they recommended me getting a ProSport 8. Thanks for the heads up on the size, I will make sure and test fit them.

One more thing - How do wet batteries hold up in high vibration enviroments. The battery tray is right up against a Wetsounds XS-XXX.

Whoa lead prices must have shot up, I was getting those for way less last year. Marine batteries are built for high vibration environments, not that they are designed to be pounded on by a sub but I'm sure they will be ok. If not they have a pretty good warranty on them. Make sure you put them in group 27 battery boxes and not the group 31 boxes, that will save you another 3" on length.

Higher resistance to vibration is one of several advantages of an AGM.
If I had two batteries with a collective amp/hour capacity of over 200 I would go with a dedicated ProSport 20. I often get a service rep on the phone and can't get quality information. I usually press to get through to an actual engineer, which isn't an easy task, who can provide good info and the reasoning behind it.

David
Earmark Marine

So i just took a look and there is no way two group 29's will fit with out major modification to my pretty battery tray. My replacements need to be the same size as the 24m-xhd.. Whats the next option? Deka SeaMate group 24 AGM?

Hey Brian, I go to Lake Travis too...I head they put in the noise ordinace there as well.

David - You said "The solution is any deep cycle battery that has the most amp/hours." So can you tell me why the D34M lasted so much long than the 24M-XHD? The D34M has 55Ah, I assume the 24M-XHD has more than that - not sure how calculate it?

http://www.interstatebatteries.com/c...o/marine_f.asp

Thats a little bit different... The city of Jonestown placed a noise ordinance on a portion of Devils Cove as their county line runs through it. Lake Travis is so big that I dont see a problem with this. Someone correct me if im wrong here. Its another story on Lake Austin - but understandable b/c its such a small lake with residences all along the shore. Especially with the amount of stereo that folks are running these days...

Brian part of the problem might be that you are using cranking batteries as deep cycle batteries big no no and thus battery is probably toast by now. Swap those with the srm-24's. These are a deep cycle/starting battery and better suited for your needs. This will probably solve your issue. I didn't notice you had cranking batteries in there before. The srm-24's will have no issue starting the boat.

Yeah Im running to cranking batteries as now. So deep cycle are more well suited for LED apllications - i got that. But will the srm-24 have enough reserve capacity to power the LED's for a long time?

Brian,
The Interstate that you referenced isn't going to hold as well because its a cranking battery rather than a deep cycle battery. Deep cycling a starting battery will lead to an early demise where as a Blue Top is intended for that purpose.
An Interstate SRM-24 group 24 Wet deep cycle has 140 minutes reserve capacity while the Deka 8A24M group 24 AGM deep cycle has 135 minutes reserve capacity. Not withstanding a more liberal or conservative approach to the specs the capcity would seem to be the same. The Deka should run about 65 to 70 percent more for the benefits of an AGM.

David
Earmark Marine

You should be able to go as long or longer than the optimas you put in there. Not as long as a bigger battery discussed but you have space limitations. Can you fit the 27 in your box. Ah is going to be king in this situation.

The Optima group 34 (smaller than a 24) is rated at 110 minutes reserve capacity (keeping all things equal) so either of the larger group 24s should be an improvement in amp/hours. As stated before the Deka AGM is a 44 percent increase in amp/hours over the Optima. Either way you're going forward.

David
Earmark Marine

I think i could pull off one 27 and one 24 but not two 27's.

ok great so i guess i will either go with the SRM-24 or Deka AGM 24.

I found a Deka 24 for $159.99 and SRM-24 for about $90

Isn't one of those sealed and the other isn't.

The Deka is sealed IIRC, probably why it will cost more. They are both great batteries

Edit - I just went back and read that you guys already talked about wet vs. AGM.

I just picked up the SRM-24's and had a thought on the way back. I could just leave the 24m-xhd's where they are at but run in them parallel - lets say to battery 1. Then run the Deep Cycles in parallel to battery 2 and run the wiring to the back locker. That would actually allow to run ANY group size. That would make two cranking batteries on switch 1 and two deep cycles on switch 2. Does anyone see a problem in this? Obviously i would install another charger.

So would you have two cranking batteries that would be on their own switch with the ability to use either cranking battery one or cranking battery two....and then combine to have one big cranking battery.

I would think this way would work b/c you could run the boat and LED's, Fog Machine on cranking battery 1 all day. Worst case scenario - you kill cranking battery one and you can turn the switch and have a fresh cranking battery 2 ready to go.

I think you misunderstood....

Battery 1 - two cranking batteries in parallel

Battery 2 - two deep cycles batteries in parallel

When the Perko is on the Batt 1 position it would be running on both cranking b/c they are ran in parallel.

When the Perko is on the Batt 2 postion it would be running on both deep cycles b/c the are ran in parallel - this is what I would run the LED's off of while parked.

The power inverter and fog machine run off of the bank of Kinetiks so thats out of the picture....

Got it now. That should work.

Damn - that is a lot of batteries.

I think you are the first guy I have ever heard of to kill a battery due to LED's

this will do it!

http://farm5.static.flickr.com/4015/...c88f1e96_z.jpg

http://farm5.static.flickr.com/4064/...b35212e6_z.jpg

http://farm5.static.flickr.com/4065/...992ce79a_z.jpg

http://farm5.static.flickr.com/4067/...40bbcafa_z.jpg

Brian that would work but I think the dual starting batteries isn't necessary. It's your reserve starting battery that doesn't get tapped for anything unless your boat dies, then you flip the switch over to that battery and start the boat. It's just taking up more room with the dual cranking batteries IMO. If you're going to move some to the back I'd go big on the deep cycle batteries.

You could even do one cranking and one deep cycle in your current battery box up front, then run a big srm-29 in the back with some 2 awg running up to the srm-24. Just a thought, possibilities are pretty endless since you're not against adding batteries in the back.

Brian,
If you are continuing to use the old cranking batteries that have been repeatedly deep cycled, then you may want to have these batteries load tested or at least measure how well they maintain their voltage after being fully charged. It places an inordinate and unhealthy load on your alternator to use batteries past their time.

David
Earmark Marine

I will get the definitely get the original cranking batteries load tested before I do anything. It's seems like a waste to toss these batterie to the side if there are perfectly fine. I will at least run one cranking and then two deep cycles for the lights. It's ok to run smr24 and a smr29 in parallel? Will the Promariner maintain them properly? I have always tried to match batteries doing stuff like this.

Brian,
Its certainly acceptable to run different size batteries on opposite sides of the battery switch but if you are paralleling two batteries on the same side of the switch then they should be the same size, type and age since they are always being discharged and charged as a single unit. This promotes longer battery life.

David
Earmark Marine

Thanks David. I really wish i could fit two 29's up front but the way the box was designed it just wont happen. I will try two smr24's up front and see how it does. If that doesnt solve the problem I'll run one cranking 24 and one deep cycle 24 up front and run the other deep cycle 24 to the back locker. Or perhaps throw one huge starting up front and a huge deep cycle in the back...

I would replace the interstates with 2 golf cart batteries and change the way you use your perko. Running both golf carts all of the time should more than double your capacity to run the boat stuff. In the event you kill the golf carts you may be able to "jump" them with your stereo batteries. This is essentially the way I have my boat setup but my batteries are significantly different. Not much downside going to golf cart batts since you are already running lead acid batteries in those locations. You might need to get taller battery boxes but they will require no more maintenance than the interstates they replace. There will be some rewiring involved but you can handle it considering all of the other mods you have done.

I saw these batteries for sale in San Antonio. I wish I would have seen these before I bought the 6v Trojans I have. Not sure if they would fit. You could probably offer him $300 for 2. Even if he didn't come down, paying his asking price of $350 for 450ah is nearly impossible to beat. If you're interested in those I could probably go test them for you before you drove down.

benjamin, thanks for the link, maybe brian and I will take all 3.... How far away from you is that guy?

I have no idea where in San Antonio he's at. I don't have anything going on this weekend so it wouldn't be a problem.

looks like i'm gonna have to run down to San Antonio to pick those trojans up

Can't say that I blame ya....it's a lot of power for not a lot of money, and 128lbs each. I was thinking about getting them, but I just bought the Trojan 6v's so I decided to see how well these do first. Let me know if you want me to check them out before you drive down

im gonna make the guy meet me in kyle or something lol.... I talked to him on the phone, real nice guy, they are only a month old. The hospital he works for required him to swap them out for some AGM cells.

Wow...looks like you're getting a killer deal then. Just to be sure, I'd check the date stamps on the terminals.

How do you read the date codes on the batteries?
Positive Terminal- Manufacturing Date. This code indicates the actual date when mechanical assembly of the battery was completed. At this point, electrolyte has not been added to the battery and formation charging has not taken place. LETTER stands for the month and could be anything from A to L (A=January, B=February, C=March, and so on),; NUMBER stands for the date.
Negative Terminal- Shipping Date. This code indicates the month and year when the battery was shipped out of our factory. LETTER stands for the month (see below); NUMBER is the last digit of the year.

Example: A battery with "I26" stamped on the positive terminal and "J2" on the negative. "I26" means that the battery was assembled, without electrolyte, on September 26th. "J2" means that it was shipped from our factory around October of 2002.

Those look like some killer batteries so long as they are in good condition as he says.

Thanks benjamin, appreciate the info.

No problem...and if you ever want to give me a pull sometime or need a 3rd let me know! lol (I don't have a wakeboard boat)

we're in austin. If you want to head up here and ride some time during the week, bring it on. Wake boarding here on the weekends is a waste of time.

I'd love to! I'll hit you up sometime. I've only gotten an oppurtunity to ride behind a wakeboard boat twice, but I've been riding cable for quite a few years....

Hahahahaha Ben you crack me up, that's awesome. You're a funny dude, I'm sure you were serious but it was funny. Sometimes the quickest way to an answer is not around the bush but directly through the bush :D.

Unvisible now you're talking on those batteries, nice score. Now the questions is where will you put them? I don't care what anyone tells you about the efficiency of your amps, the more battery the better. Just make sure you can take care of them with your charging routine.

haha! yeah, I guess I'm that guy, but don't want to be that guy, and kind of in a denial about it.

No worries you are in good company...

my wetsounds amps are already here.

Gonna install each one in the back locker on my 210.... and take up 4 of my optimas :D

Yeah I can see this presenting a problem if you have the wedge tanks in back and knowing you have a sub in your observers compartment. Where there is a will there is a way. I wrestled with where to put my 8D's but it all worked out. However, I still need to dress them out.

How necessary is a battery box? I was planning on fabricating my own, but if they're strapped down and secure is a battery box still essential?

I had mine in all season without one, nor do I intend to get them but rather fabricating something to hide them.

i have the wedge tanks, but i'll still figure it out.

get some boyyyyyyyy

http://a4.sphotos.ak.fbcdn.net/hphot..._3938246_n.jpg

no reason for coilovers - trojans on all four corners

I bet you needed that gatorade after having to lift and carry that thing!

120lb each, aint no thang

Yeah those ore gonna have to be upright too. I say ditch the wedges put those as far back as possible (one on each side) and replumb some smaller sacks and you'll be ahead of the wedge weight. Then you got yoself some play time!

I got to admit, I'm kind of jealous! lol. I would have bought those if I didn't get the Trojan 6v's a week prior to finding those. I like how there's 2 posts on the +/-. The 6v's only have one. So did you get all 3?

Yeah, I picked up all 3. Probably just gonna use 2 though..

they fit :D

http://i55.tinypic.com/2ho8bpj.jpg

I'm building 1/8th steel bases for them so they obviously wont be sitting on the tanks... Should be about 2" of room to connect the terminals... I'll have one trojan on each side of my boat. Gonna be real nice to never have to worry about running out of juice :D

Don't jerry rig it, put them in some sort of battery box even if you have to make it yourself.

they will have a containment tray, but I wont be building a full box for them... I dont think i'll need it.

http://i54.tinypic.com/25jwdh2.jpg

first design we're trying.. we'll see how it works before we build 2..

That's a lot of battery! Good luck!