Battery choice

[regis101]

Ya know, for as simple as it wants to seem, I'm having a hard time picking a battery(ies).

The more knowledge that I think I'm getting the more cornfused I get.

My present thought is , pound for pound - amp hour per amp hour, one should just step on over to twin GC's and call it good.

If I know that my daily load calc's out at ~30 Ah, having the ~200 Ah GC capacity allows about three days worth before thinking about charging back up? Yes, there are other factors but I'm trying to get a general rule of thumb here.

I use US Battery for reference since their site is easy to navigate. Why would I want two G24's for 85 Ah at ~50% when two GC's would give ~100Ah at 50% and the weight is pretty close between the two . Factor in the better hammering of the GC batteries vs the 12v DC's and it seems a no brainer?

Hopefully this makes some sense. I can't type as fast as I think, I think.

Just trying to get the gist of all things 12v

 

[highdesertranger]

there is no doubt the 2 flooded golf carts are the best bang for the buck. I would like to point out though going 3 days without charging is not good for any battery. it is best to recharge to 100% daily. this will give you the longest battery life. that is why solar is so good, because it charges every day. highdesertranger

 

[MrNoodly]

However, if you don't want to deal with venting and maintenance, go with sealed batteries.

 

[regis101]

Thanks for the replies. More food for thought.

My rig is/was woefully under powered. I've upgraded the wiring and have a 55 amp converter coming. I am confident of being on the right track with the added thought of future expansion., i.e. gen set, solar, number of appliances.

I have the ability to stay plugged into shore power here at the house. My wintertime camping is usually at full hook up sites just because. Warmer weather has us in non-utility sites a bit more.

We are basically weekend warriors. This is why I'm looking at a three day battery capacity. And if adding solar is the thing to do then so it shall be.

 

[SternWake]

This photo explains why one does not buy 2 group 24 12 volt batteries instead of two 6v GC-2's

Source and a very good read.  Also it has been updated, for those who have already seen it before.

http://www.pbase.com/mainecruising/deep_cycle_battery

 

[regis101]

That is indeed a good read. Thanks.

I've been reading up on the AGM. Kinda nice for this newbie. They seem a bit forgiving, not gassy and user friendly.

My battery location is under the bed/bench/couch area. No problem with FLA and associated maintenance if I build a batt box. No problem with the AGM in that location also.

What I notice is within the pages and pages of inter web info, there is always that one or two magical sentences.
Am I correct to recap that AGM's no not want the equalization stage? A three stage charger is just fine?

If so, then the 55 amp four stage charger due to arrive tomorrow may do more harm than good to the AGM's?

I learned a bit about the ~C/3 charge rate for FLA's and For the AGM, I saw C/20 as well as Cx4? Need to go back on that one.

I'm trying.

 

[regis101]

That is indeed a good read.  Thanks.

I've been reading up on the AGM.  Kinda nice for this newbie.  They seem a bit forgiving, not gassy and user friendly.

My battery location is under the bed/bench/couch area.  No problem with FLA and associated maintenance if I build a batt box.  No problem with the AGM in that location also.

What I notice is within the pages and pages of inter web info, there is always that one or two magical sentences.
Am I correct to recap that AGM's no not want the equalization stage?  A three stage charger is just fine?

If so, then the 55 amp four stage charger due to arrive tomorrow may do more harm than good to the AGM's?

I learned a bit about the ~C/3 charge rate for FLA's and For the AGM, I saw C/20 as well as Cx4?  Need to go back on that one.

I'm trying.

Just read a good thread on a boating forum and the IOTA DLS-55 with IQ4 came up a compatible with AGM's. It seems that their fourth stage isn't that high in voltage.

 

[SternWake]

AGMs are indeed good, however they really enjoy being 100% recharged and are not nearly as tolerant of partial state of charge cycling as true deep cycle flooded batteries. They are not forgiving of less than full recharges.

The price has people thinking they are a super battery, but in deep cycling service one really needs to ensure that they can actually get them to a true 100% state of charge every X number of cycles. I say X instead of a number as different AGMS respond differently to PSOC cycling.

My Northstar AGM seems to start protesting at 5 to 7 deep cycles without a 100% recharge and at 12 to 14 cycles of PSOC becomes downright petulant. At this point a full recharge requires a significant amount of time to occur, and this particular battery also demands a high amperage recharge rate from its most depleted state.

When the time held at absorption voltage is not attained, not only is the battery not fully charged, what is worse is the human having complete faith in their charger/converter can be blissfully unaware of it, and the battery will lose capacity faster.

I hope the 55 amp converter you ordered is Iota and not Wfco.

Really, Charging perfectly can be taken to ridiculous extremes. Researching what any specific battery desires is wise, but a few tenths of a volt or slightly higher or lower than the 'recommended' charge rate or absorption voltage, is not going to cause instant death of the battery. Just that fact that an owner is aware it is less than ideal will likely have the batteries last longer than the person with full faith in the marketing mumbo jumbo of any product.

When a converter advertises an Equalization stage, it is marketing BS.
An Equalization is a forced overcharge, bringing the battery to 15.5 to 16.2 volts for a period of time until all cells in the battery are brought to their maximum.

The converter marketers so loved the marketing potential of this word, they adopted it and bastardized it and should be strung up by their short and curlies and whipped until they accept they chant over and over again that "Destratification is NOT Equalization".



A 15 minute bump upto 14.X volts every 18 hours from the storage/float mode(13.2 volts) causes bubbling, which mixes up the electrolyte. Without this the denser heavier acid sinks to the bottom of the cells and eats the plates at a faster rate. This only occurs when the flooded battery is left on the converter, which is plugged in for long periods of time.

Note that AGMS do not require this Destratification, and it is unnecessary, unneeded, but it not going to kill them either. Especially since it is likely the converter dropped to float voltage prematurely anyway.

Simply put, do not stress the '4th stage', it is beneficial for flooded batteries, and will marginally practically immeasurably negatively affect AGM batteries, and only on those batteries that spend weeks or months on end plugged in without ever cycling the batteries.

Do note that flooded batteries should be vented to a space exterior that of the living quarters. Even AGM batteries will say to not put in a sealed container.
Offgassing of flooded batteries is a touchy subject with very strong very loudly typed opinions(always stated as incontrovertable facts) on either side, and always derails threads, so I'd recommend doing a search and not opening that can of worms in this thread.

As far as charge rates, C/3 would be capacity divided by 3. So 33.3 amps for a 100AH battery. Capacity should be stated as Amphours at the 20 hour rate as that is standard, but is not always.

I generally say 20% or 30% charge rate, meaning 20 amps or 30 amps per 100Ah of capacity.

AGMS should get no less than 20% when cycled to 50%.
Trojan recommends 10 to 13%, but that recommendation is for a golf cart, which gets 8 to 15 hours to plug in and will ensure a full charge before the next discharge cycle begins.

When Rv dwelling, a higher charge rate is beneficial if it means starting the next discharge cycle at or at least closer to 100% state of charge. In general do not fear a higher charge rate than the published 'recommended' charge rates, unless it is grossly higher, and the ambient temperatures are above 85 degrees.

When relying on batteries day in and day out, the higher charge rate for shorter generator run times will save money in both battery replacement, and gasoline to run the generator. Ideal charge rates for maximum life are almost meaningless when one is cycling the batteries every day.

At higher rates of charge the batteries do heat considerably, so confined in an enclosed space is not ideal, but again not instant death either.

 

[regis101]

* humbly bows * Thank you sir. Your knowledge and kind wording make for a learned experience.

IOTA DLS-55 w/IQ4 on its way, yes. It will suit (this) coach properly and with a bit of room for future expansion.

Regards,

 

[regis101]

Just adding that for the , just because, reason, I fired off and email to IOTA Tech Support asking if their DLS charger with the IQ4 can be used with AGM's. I have no problem with basic FLA 6v batteries if I build a vented box. That's easy.
My inquiry to them is to see what they say.
I'll chime in with their reply when they reply.
Thanks,

 

[IGBT]

I have been running Lifeline group 31 125AH 12V AGM batteries in our RV for over a year and have not noticed any real decline in capacity.   I have not even looked in on them in six months.   Our solar brings them up to full every day with about 30 amps of charging current to the 24V system.  It is exactly what I wanted, wire up correctly and then forget about them for a few years.

Until lithium gets more mainstream.   Tesla powerwall please!

 

[regis101]

This is a copy/paste from the email a had sent.

*Our DLS with IQ4 are used with AGMs every day. You will not have an issue with overcharging the batteries.*

 

[SternWake]

This is a copy/paste from the email a had sent.

*Our DLS with IQ4 are used with AGMs every day. You will not have an issue with overcharging the batteries.*

Broad statements have outliers

Lifeline AGM, made by Concorde, which are likely the best Deep cycle AGM battery, have a max recommended bulk/absorption voltage of 14.2 to 14.4v at 77f

But it is not as if 14.8v and the time the Iota with IQ4 will bring and hold the battery above 14.4v is going to instantly kill them, nor is it even likely to noticeably shave off any measurable lifespan, outside of a laboratory environment.

Lifeline's technical manual is a very good read for the battery newbie, on how to care for any lead acid battery.

Scroll to page 19 for charging:

 http://lifelinebatteries.com/wp-content/uploads/2015/12/manual.pdf

http://www.rollsbattery.com/wp-content/plugins/rollsbatteries/pdfs/Rolls_Battery_Manual.pdf

If members here were to read and understand both the above links, I would have little to write about on this forum

 

[regis101]

SW wrote:
*If members here were to read and understand both the above links, I would have little to write about on this forum*

Oh no no no. Your'e not getting outa here that easy.

 

[highdesertranger]

x2^^. highdesertranger

 

[Dirk Mitchell]

I am about to pull the remaining interior out of the back of my van to start building the rear bed platform. The electrical system will be under one side in front of the wheel well. I ordered a few things already to start getting it wired. I am very familiar with residential and commercial AC wiring but I am a novice when it comes to DC and solar systems. As I mentioned I have a few things on the way:

Stinger SGP32 200 AMP Battery Relay Isolator and Relay
Flexible 0 Guage Wire -- 25 feet to run back from the main battery 
Blue Sea Systems Fuse Block -- May be too many circuits but I need to stay organized for sure. 

I am not sure on batteries, I want to have them under the Van mounted to the frame rail eventually, However, since I am learning as I go on the setup I think I will set them up in the van in the beginning and then move them under later. Because of that I am leaning towards AGM. I had some bad experiences with Optima and someone on Sportsmobile Forum asked about these:
Exide Edge FP-AGM34 Flat Plate AGM Sealed Automotive Battery -- They look a lot like the Lifeline batteries. They have very good reviews and a full replacement 48 month warranty so that is a bonus as well. I am thinking I will get one of these to get set up and then maybe a second depending on how much I end up needing. 

I already picked up my inverter as well ([size=small]ENERGIZER 2000 Watt Power Inverter open box special on Amazon just over 100.00!) I am hoping to be able to run my saw and a few other tools (one at a time) when power is not available on a job. Due to the inverter size I may need another battery. The price on the Exide ones isnt to bad so I can probably get a second one fairly soon. [/size]
[size=small]I have a roof rack I am putting on tomorrow, after I measure the rails on it I am going to look into what solar panels will fit between the rails to be semi stealth and go from there. [/size]

 

[SternWake]

Ideally you would want to get your batteries at the same time. While it is hard to say the results of newer and older in parallel, in general the older drags down the newer one and capacity is not 2x of one battery but somewhere considerably less, and capacity will decrease faster.

I like that you got some thick cable for alternator recharging, but those Exides are one of the batteries that are not so happy with very high charging currents, which is one of the main benefits of AGMS.

http://www.exide.com/Media/files/Do...ery Charging & Storage Guidelines 5_9_13.pdf

This ^^says a 100Ah exide Edge plate plate AGM should NOT be charged at more than 50 amps, which is better than the 30 amps many other lesser$ AGMS list. BUT You might be bouncing off or above a pair of group34's upper limits at freeway speeds with 0AWG cabling. Exide is also saying a 14.1 to 14.4 max voltage and your vehicle might exceed that.
My opinion is an AGM battery intended for high loads should not have these lower charge rates and voltage restrictions placed upon them, that the restrictions indicate impure lead plates( higher self discharge), higher resistance( lower CCA figures) higher heating during charging, and require more of a percentage of energy returned to them to be considered fully charged.

The TPPL AGM batteries are much better at powering large inverter loads, their voltage will not sag as much, AND they have absolutely no issues accepting Huge recharging amperages.

While Lifeline AGM batteries have no real charge amperage limitations, they do not have the super high CCA of Northstar or Odyssey and LL voltage will sag more under high inverter loads, but the Lifeline will easily out cycle the TPPLs when properly recharged. Odyssey and Northstar will also recharge faster at the same applied voltage, all other factors being equal too, but not by any huge percentage.

TPPL is Odyssey, Northstar which is relabelled as X2Power by Batteries + and has the nationwide 4 year free replacement warranty. I'd say go for group 31's instead of group 34. 31s have 100Ah capacity, 34s are significantly less.

The Solar is pretty much a requirement for reaching 100% state of charge, and 100% state of charge is a requirement for getting ones money worth out of high $$ AGM batteries, so I recommend you really stuff as much solar as you can fit within your racks, and an MPPT controller should be able to squeeze out the most from that wattage, and likely allow user adjustable absorption voltage and float voltage setpoints which also allow one to extract more lifespan from a battery.


INverters need to be able to handle the start up surge of power tools, Often the lesser inverters surge ratings are of very short duration. Hard to say whether it will or will not be able to start your saw. If the saw is NOT a soft start one could throttle it down via a router speed controller on initial trigger pull then dial it upto full speed.

https://www.amazon.com/MLCS-9400-St...37516&sr=8-1&keywords=router+speed+controller

I've had good service from this one^^

At some point early in the battery's lives, You might also want to consider a high amperage plug in charging source for those times you have grid power.
The progressive dynamics PD9260 with charge wizard is pretty good.

There are a 14.4v and now a 14.8v absorption voltage model available. 14.8v is faster but does exceed, slightly, the max recommended voltages of both Odyssey and Northstar, but unless the batteries and or ambient temperatures are really hot, over 85F or so, there will be no issues with it, and argueably they could be better off for the higher voltage.
I would not treat the lesser$$ AGMS the same way, as these will definitely heat more at higher amperages.

http://www.bestconverter.com/9200-148-Volt-Deck-Mount_c_227.html
If you go with the lesser Exides get the regular PD9260 with its 14.4v max absorption voltage.

Do not forget to fuse close to the house battery bank, 0AWG should be fused for no more than 150 amps. Do run the wire from fuse holder to Alternator (+) stud, run it in some split loom, and make sure it cannot chafe or vibrate. The Alternator(+) stud will greatly increase charge amps compared to taking power from engine starting battery, and likely be a shorter circuit too. It could allow the vehicle's voltage regulator to hold a higher voltage for longer too

https://www.amazon.com/Bussmann-CB1...38472&sr=8-1&keywords=150+amp+circuit+breaker

https://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias=aps&field-keywords=anl+fuse+holder

The quality of your ring terminals and their crimps is vital. Hammer crimps at 150 amps is not acceptable. Minimizing voltage drop is important for effective alternator recharging and for powering a 2000 watt inverter at its limits.
http://www.genuinedealz.com/marine-...e-connectors/tinned-copper-cable-lugs?cat=195

http://www.pbase.com/mainecruising/battery_cables

Do it right the first time, or at best, you get to do it again the next time. At worst, the van goes all Fukushima/ Chernobyl on you.

If your saw does not run on the inverter, try starting the engine to raise the input voltage, and minimize draw on the batteries, but do not idle for more than 10 minutes maxing out the alternator. It will overheat.

Slide the sensor from this Ammeter over the 0 awg cable between ANL fuse and circuit breaker and house battery(+) terminal to see charging amps, or on inverter cable to house battery cable to see inverter load. You can run the wire to the fuse block through it too.

https://www.amazon.com/bayite-Digit...8&qid=1481439140&sr=8-3&keywords=bayite+meter

If you ground house batteries to vehicle frame, Add another ground cable, 0 awg, from frame nearby alternator to Alternator mounting bolt or engine nearby. Take steps to ensure a very solid long lasting frame ground. They become problematic all too easily and are overlooked.

The Stinger Solenoid, you might want to put an illuminated inline switch on its trigger circuit. Wet engine belts and depleted batteries could cause the alternator belt to slip squeal and glaze on startup in morning. Wait until engine warms up some then flip switch and it should prevent the squeal and reduce load on cold engine.

 

[Dirk Mitchell]

Man all kinds of good info. After all that I am thinking I may end up going with some 6v golf cart batteries to start out. I was trying to avoid maintenance and have them be sealed but in order to get over the 200AH and be around 300.00 I think the 6v pair may be the only way to go. Or Ill have to wait a bit and buy a couple AGMs together since it sounds like I don't want them to be different ages.

 

[SternWake]

6v gc-2 batteries are excellent deep cycle batteries, very tolerant of abuse.

However, for your intentions of occasionally loading the inverter with a 2000 watt load, they will not be able to support the load for nearly as long as AGM batteries before low voltage alarm starts screaming, or even 12v marine batteries of equal or even lesser capacity than the GC-2s.

Golf cart batteries are not rated for CCA, but I estimate they would only be about 900CCA or less in a 12v pair wired in series, where a pair of group31 flooded marine batteries in parallel would be 1300 to 1400CCA, and a pair of Northstar or Odyssey group 31s in parallel would be 2300CCA.



IF you are willing to run the engine when running the saw, or other huge inverter load, then this negates the advantage of the AGMs higher voltage retention, for a much lesser price.

Best of luck

 

[Woltz]

My biggest purchase regret was not buying something from Craigslist. Someone had 15 Deep Cycle Batteries for $25.00 each. Brand new. Those nice tall ones you never can afford.