6 Volt batteries

[Skyman]

My Roadtrek came with two brand new 6 volt batteries and I was wondering about the difference between these and the 12 volt batteries. Any advice or knowledge would be appreciated.
Also some guidance on Class B storage and odds and ends you learned folks take with you. We love our dog and have a new puppy on the way. We discovered our 200 pound Irishwolf can’t turn himself around in the B. He has to back out to the door to turn around so we are devising a way to fill in by the side door to give him more space. The new pup is a Cane Corso, not as large but not small either.
Thanks all!

[rowiebowie]

Little difference between 2 - 6 volts wired in Series or 2 - 12 volts wired in Parallel. It all comes down to what fits and getting the most useable amp hours. Some have reported being able to get a bit more amp hours from 2 - 6 volts, but probably only 5-10% more.

The most important questions should be the choice between: Wet-cell deep cycle (cheapest and most maintenance intensive), AGM sealed batteries (a bit more expensive but don't off-gas or require water replenishment), and Lithium Iron Phosphate (way more expensive, will require replacement of other components with lithium-compatable ones and subject to extreme cold limitations, but will nearly double your available amp hours at half the weight).

[avanti]

Agree that the differences between 6v and 12v are small. One advantage of 12V is that if one battery fails, you can disconnect it and still have the other one work.

[themexicandoctor]

Originally Posted by avanti

Agree that the differences between 6v and 12v are small. One advantage of 12V is that if one battery fails, you can disconnect it and still have the other one work.

How often does this scenario happen if you are dealing with high quality, tier one* AGMs like Lifeline?

Because if there is a failure, its a smart point but then again, the offending battery would be replaced in 48 hours or less.

*price point again, $385 versus say $125 for a Dekka or Trojan Battery - I went onto the Penn websites & studied everything including their 5 year warranty - they are the most cost effective units out there.

[GeorgeRa]

Originally Posted by themexicandoctor

How often does this scenario happen if you are dealing with high quality, tier one* AGMs like Lifeline?

Because if there is a failure, its a smart point but then again, the offending battery would be replaced in 48 hours or less.

*price point again, $385 versus say $125 for a Dekka or Trojan Battery - I went onto the Penn websites & studied everything including their 5 year warranty - they are the most cost effective units out there.

Apples to apple comparison between 2 x 115Ah @ 12V = 230Ah @ 12V and 2 x 224Ah @ 6V = 224Ah @ 12V normalized to 224Ah is $8.84 from https://www.wholesalesolar.com/brand...?orderby=price

I see no reason to go to 6V in the world of AGM, from my perspective going to Trojan lead acid flooded batteries is a good option, but in the 21 Century of AGM it is not.
I have not yet seen a good engineering reason why 6V AGM batteries are better then 12V.

[avanti]

Originally Posted by GeorgeRa

Apples to apple comparison between 2 x 115Ah @ 12V = 230Ah @ 12V and 2 x 224Ah @ 6V = 224Ah @ 12V normalized to 224Ah is $8.84 from https://www.wholesalesolar.com/brand...?orderby=price

$8.84 sounds just about exactly what the extra redundancy of the 12V batteries is worth. Free markets are amazing things.

[themexicandoctor]

Originally Posted by GeorgeRa

Apples to apple comparison between 2 x 115Ah @ 12V = 230Ah @ 12V and 2 x 224Ah @ 6V = 224Ah @ 12V normalized to 224Ah is $8.84 from https://www.wholesalesolar.com/brand...?orderby=price

I see no reason to go to 6V in the world of AGM, from my perspective going to Trojan lead acid flooded batteries is a good option, but in the 21 Century of AGM it is not.
I have not yet seen a good engineering reason why 6V AGM batteries are better then 12V.

I hear you George & Avanti,

You are two of the Technology Giants amongst us I refer to.

I am choosing to go with the 6 volts simply because of the Size Considerations, the 6 volt units are 1/2 inch taller than the 12 volts but they are 3 inches less in width.

Under the bed is 12 inches height to work with.

As I mentioned on another couple of posts, the original Roadtrek came with one 12 volt battery located on a tray behind the rear tire but on top of the exhaust (highest temp ever recorded by me was 46 degrees but the other day, it exceeded 52 degrees F).

Then I added another 12 volt, in the optional space in front of the rear tire with about 3 feet in difference (6 feet in cabling), which both my Electrical Guru & Booster pointed out, leads to an imbalance immediately that over time, cumulatively causes either undercrhing or overcharging issues. Unless one does the work around.

Which was going to cost money plus the exhaust issue.

I could get the 12 volts in the resize wise but felt the extra run time of the 6 volts was a win win situation.

By doing this I am also eliminating the extra distance in running the Solar coming off the drivers side & then running into the shunt & electrical which is placed up front of the bed, next to the rear wall of the kitchen - as well as shortening the battery to shunt run lengths.

Here are a couple of photos of where the new install is going to happen.

[avanti]

Originally Posted by themexicandoctor

I am choosing to go with the 6 volts simply because of the Size Considerations, the 6 volt units are 1/2 inch taller than the 12 volts but they are 3 inches less in width.

Seems like as good a way to decide as any.

[themexicandoctor]

Originally Posted by avanti

Seems like as good a way to decide as any.

I think you were being sarcastic & that's ok.

The primary reasons are;

1. I trust Lifeline with my Life.

2. I don't believe one unit or either will fail.

3. I could go ahead with the almodt 2 year old 12 volts but they most definitely require being placed at the rear of the under bed area because of the extra size.

By the way, the 12 volts passed all the tests with flying colors, just a small difference between the two batteries.

4. No-one has answered the question yet, but by placing the batteries either 6 volt or 12 volt, closest to the electrical box, I presumed there would be less chance of voltage loss with the shorter run.

If it were you & you had the opportunity to either leave the Inverter where it is, outside of the original box but directly behind it OR you could place the batteries up against the box (with space for cooling), & move the inverter back, what would you choose?

I am not doing the work, my RV Guy is. The cost of the shuffle is unimportant compared to the increased efficiency.

[avanti]

Originally Posted by themexicandoctor

I think you were being sarcastic & that's ok.

No, I wasn't being sarcastic. The point is that there are only tiny differences between 6V and 12V. If one fits better, that really is as good a reason as any.

1. I trust Lifeline with my Life.

Now, THAT I don't resonate to. Lots of people pay lots of money for a three-pointed star, or the fancy bottle around their filtered water. In any market, there are brands that can afford to charge a premium because they have managed to gather an aura around a trademark. If that's your thing, fine. I can't get into it. This is not to say that Lifeline isn't a fine product. But all interesting questions are questions of cost-effectiveness. Color me skeptical.

I am even more skeptical about "gurus" who have vested interests in the advice they give. I pay extra for a financial advisor who doesn't make commissions on what I buy. I bet it saves me money.

3. I could go ahead with the almodt 2 year old 12 volts but they most definitely require being placed at the rear of the under bed area because of the extra size.

By the way, the 12 volts passed all the tests with flying colors, just a small difference between the two batteries.

No right or wrong here. If reclaiming the space is worth the money to you, carry on. Please don't send those perfectly serviceable batteries to the recycler, though. I bet somebody would be glad to have them.

4. No-one has answered the question yet, but by placing the batteries either 6 volt or 12 volt, closest to the electrical box, I presumed there would be less chance of voltage loss with the shorter run.

Voltage loss is not a matter of chance. It is physics. Longer runs are fine, they just need bigger wires for a given voltage drop, so it is a matter of cost, weight and space. Yet another cost-effectiveness question.

[themexicandoctor]

Thank you Avanti,

You answered my questions.

As for the price point, I in the past have always felt my Battey Naivete, required more Wiggle Room.

I have a sense I am on top of those issues now and I have a loyalty to Lifeline & their AGM technology.

And its not Apples & Oranges however there are many users amongst us, that dot mind walking into Peo Boys, Kragen or Walmart, etc & demanding they replace the 6 month old unit they purchased.

I do have an Odyssey Extreme as my truck starting battery - about $375, money well spent in my eyes.

[mkguitar]

Given a choice between 2x6's or 2x12's I'd always go for 12's- I could run off one battery in event of a failure

Originally Posted by themexicandoctor

I do have an Odyssey Extreme as my truck starting battery

I had an odyssey short internally and burn up

that one had replaced another odyssey under "warranty" which went open internally

and was when I stopped sperimentin'

I hope you have better luck than I !

Mike

[eric1514]

If I have easy access to the batteries, I will go the 6v route as GC batteries are cheap, truly deep cycle and easily available at any Costco. They're less than $100/each, so <$200 for 210Ah, <$400 for over 400Ah all available at over 700 locations in NA from a retailer with a generous return policy.

[Bud]

Originally Posted by eric1514

If I have easy access to the batteries, I will go the 6v route as GC batteries are cheap, truly deep cycle and easily available at any Costco. They're less than $100/each, so <$200 for 210Ah, <$400 for over 400Ah all available at over 700 locations in NA from a retailer with a generous return policy.

AMPS per DOLLAR

Is there a better deal out there than what your have described?

[eric1514]

Originally Posted by Bud

AMPS per DOLLAR

Is there a better deal out there than what your have described?

Except that my math is wrong. 2 105 ah 6v GC batteries = 105 ah at 12v. So 105Ah = $200. My bad. Still, a good deal, but not the great deal I posted previously.

[Bud]

Originally Posted by eric1514

Except that my math is wrong. 2 105 ah 6v GC batteries = 105 ah at 12v. So 105Ah = $200. My bad. Still, a good deal, but not the great deal I posted previously.

"AMPS per DOLLAR

Is there a better deal out there than what your have described?"


Ok, 2 group 31 are about the same deal. Still, Amps per Dollar is about as good as it gets, it seems.

Bud

[booster]

Originally Posted by Bud

"AMPS per DOLLAR

Is there a better deal out there than what your have described?"


Ok, 2 group 31 are about the same deal. Still, Amps per Dollar is about as good as it gets, it seems.

Bud

It all depends on if you are looking for cold starting AMPS, or deep cycle AMP HOURS.

[Bud]

Originally Posted by booster

It all depends on if you are looking for cold starting AMPS, or deep cycle AMP HOURS.

Thanks booster, but I don't understood.

A Costco 6 volt gc costs $99 times 2 = $198 total amps at 20hr rate is 210 12v amps

A Costco 12 deep cycle gc battery costs $239 dollars total amps at 20hr rate is 150 amps

Are there less expensive 12 volt amp hours than 2 6v gc batteries?

[booster]

Originally Posted by Bud

Thanks booster, but I don't understood.

A Costco 6 volt gc costs $99 times 2 = $198 total amps at 20hr rate is 210 12v amps

A Costco 12 deep cycle gc battery costs $239 dollars total amps at 20hr rate is 150 amps

Are there less expensive 12 volt amp hours than 2 6v gc batteries?

The problem is that you appear to be measuring battery storage capacity, the important part for camping, in AMPs, which is not possible. Especially the the gp31 will have a rating in AMPs, but it will cold cranking amps for starting. It might even be reserve amps, but then will have a time for those amps being used. It may or may not also have a rating in AMP HOURS, which would be the 20 hr rate you just now referred to and is the capacity.


Amps and amp hours are not the same thing as on measures instantaneous power and the other is how much power can be stored and used later.



The manufacturers started to use the terms interchangeably a few years ago, mostly to confuse people into not being able to accurately compare batteries, and of course to make theirs look better than they were. Roadtrek was a leader in this deception (previous owners, not current ones).


Obviously, that confusion has worked well, as we see this kind of confusion all the time now.

[mkguitar]

it's like tires


load range


load index


c'mon fellas!