Best deep cycle ?

RJsfishin wrote:
Prove it !! AGMs don't last longer, and they cost double. Simple math if ya ask me !

I don't know what "Prove it" means, exactly, in a non-scientific context, but I will say this: I have a couple of 7 year old AGMs still going strong in our RV that are being almost entirely taken care by only the stock Parallax ~13.8 fixed voltage converter in the RV.

Does anyone here have 7 old liquid acid RV batteries that have been, the whole time, taken care of almost entirely by a good old stock fixed voltage converter? If they do, please speak up so as to simultaneously debunk my "proof" while at the same time show that multi-stage chargers are in fact not absolutely required to get superb life out of LA RV batteries.

mena661 wrote:
Why would you need a car jar battery when tent camping?

Well ... that depends upon whether or not you wanted to be comfortable on cold nights in your tent without being all gussied up in a sleeping bag.

Using a 100 AH "car jar battery" one could easily have one of these inside the tent to safely and quietly keep the chill out all night long (assuming the liquid acid car jar battery was left outside the tent):

http://dealspl.us/sharper_image_worlds_smallest_big_heater_81097

We have two of these little wonders. They'll run off a small inverter and are two speed - 150 watts (12 amps at 12 volts) on HIGH, and about 75 watts (a little over 6 amps at 12 volts) on LOW. They're very efficient at conversion of electricity into heat, too - as their case does not warm up at all when they're heating. All of their heat comes directly and only right out of their little adjustable front grill.

P.S. Of course when I sleep in the cab of our 4X4 truck when out and about, I power one of these with a special (no longer available) 90 AH yellow-top Optima AGM battery so the battery can safely be used right in the truck's cab to keep the battery warm for maximum battery life. In a tent, one would want to power the heater with an AGM battery, too, so that the battery could be right in the tent with you keeping itself warm.

Why would you need a car jar battery when tent camping?

Some background info, tplife is a tent camper with a single AGM battery which is used to operate some lights and music. He is convinced that AGM is the only battery worth having and regularly debates the topic on this and another forum I frequent.

His opinion is certainly valid as to what works best for him and makes him happy. I agree that for his use an AGM is best. His battery isn't mounted, is handled frequently and cannot spill.

However you will never convince him that AGM technology is not best for every person and in every situation. He seems to have blinders on, quotes erroneous experts, and is absolutely convinced of his opinion.

tplife wrote:
RJsfishin, I paid $120.00 for my Optima vs. $80.00 for the Costco marine flooded battery, an extra investiment of $40.00 more for my example...and the AGM has far exceeded what I expected for a power source. AGMS are rated to last 2 to 3X longer than flooded batteries, at least according to a lot of their customers. There are too many advantages to list here, but like pre-'75 cars, folks cling to what they know and love rather than what they buy and try!

Lets say you needed 100Ah usable capacity from your batteries, and your main charging system was from the vehicles alternator. Now with conventional deep cycle batteries because you would only have 25% of your battery bank usable you would need 400Ah of battery bank, now there are a few ways you could do this, but the least expensive way would be four x 225Ah 6 volt Trojan batteries at a cost of $1,120. Now with AGM batteries you could have just two x 100Ah giving you 200Ah total, so there is your 100 Ah with heaps in reserve and an easy life for the batteries, so only 2 batteries, at a cost of $710 all up, or better still you could use a single 200Ah battery for a cost of $695.00. - See more at: http://www.fridge-and-solar.net/agm.htm#sthash.lE3bx5yy.dpuf

Your assumptions about use and price is definitely flawed. The comparison is not accurate. I choose not to explain it, I'm pretty sure everyone knows.

RJsfishin, I paid $120.00 for my Optima vs. $80.00 for the Costco marine flooded battery, an extra investiment of $40.00 more for my example...and the AGM has far exceeded what I expected for a power source. AGMS are rated to last 2 to 3X longer than flooded batteries, at least according to a lot of their customers. There are too many advantages to list here, but like pre-'75 cars, folks cling to what they know and love rather than what they buy and try!

Lets say you needed 100Ah usable capacity from your batteries, and your main charging system was from the vehicles alternator. Now with conventional deep cycle batteries because you would only have 25% of your battery bank usable you would need 400Ah of battery bank, now there are a few ways you could do this, but the least expensive way would be four x 225Ah 6 volt Trojan batteries at a cost of $1,120. Now with AGM batteries you could have just two x 100Ah giving you 200Ah total, so there is your 100 Ah with heaps in reserve and an easy life for the batteries, so only 2 batteries, at a cost of $710 all up, or better still you could use a single 200Ah battery for a cost of $695.00. - See more at: http://www.fridge-and-solar.net/agm.htm#sthash.lE3bx5yy.dpuf

Probably will replace those Neverstarts about every year and a half. They are actually modified starting batteries. Best true deep cycle in my opinion is the Trojan T 105 (for RVing use) I average over 8 years per set ad they're used HARD.

I think the OP is satisfied.

Quote:
.manufacturers) offers AGM options that are far superior to flooded batteries
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Far superior ?????

Prove it !! AGMs don't last longer, and they cost double. Simple math if ya ask me !

DryCamper11 wrote:

My personal opinion is still that FLAs, such as Sam's Club 6v's are the best bank for the buck. Some of us are willing to pay more for less hassle - no water checks. Some need the reduced gas venting of AGMs or the ability to mount them on their side, etc., and some can use the faster recharge rates if they have a small battery bank and a big charger. However, for me, the bang for buck is the prime concern and FLAs can't be beat.

Great post! I even learned some things which is always good. I was about to pull the trigger on AGMs when I was in the planning stages of my battery bank. My original budget was $2500 for batteries. There were a few things about AGMs I liked (these were for Lifeline AGMs):

1. Can be taken down below 50% SOC repeatedly - 500 cycles doing this, not sure this can be done in reality
2. Fast charging - I planned on 200A worth of charging
3. Less maintenance - I know people say no maintenance but I disagree
4. Can be placed on their sides, etc - I planned to put them on end
5. Don't necessarily need to be floated, at least not in the short term. - You will get more life if you float them

I ended up getting L16 FLAs instead because they were cheaper ($1100), can be taken down to 70% SOC repeatedly. Can be charged with 200A worth of chargers also (saved a few thousand here cause I can use converters instead of the inverter/charger and separate charger I planned to get). They were tall and skinny so no need to put them on their sides. They do require floating and more maintenance but the maintenance ended up being easier and not as often as I suspected.