Battery technology differences

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Gary RV_Wizard

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I came across this article, "Automotive Battery 101", on the East Penn Canada web site. East Penn is one of North America's largest battery manufacturers and this is their Canadian operation's web site.  It gives readily understandable descriptions of the difference between flooded, AGM and Gel as well as starting vs deep cycle (cycling) batteries. Also included are battery terminology, reasons for battery failure, reasons for power loss, etc. Check it out.

http://eastpenn-powerbattery.com/batteries_automotive.php
 
I thought I had detected an error in the article text where it was stated that the positive plate paste was transformed to "Lead Dioxide" by the forming process.  I had always understood it to be "Lead peroxide".  Consulting the MSDS shows them to be the same thing. :eek:

I knew I should have stayed awake in Chemistry. :-[ 
 
Gee Gary don't you know there is no difference between starting and deep cycle?  I mean just any of the deluded folks on the other forums we visit that are always telling me that.

(OH, you believe them like I believe them.. Not at all)  Of course there's a difference.

Good article, Picked up a couple of points,  Thanks.
 
John From Detroit said:
Gee Gary don't you know there is no difference between starting and deep cycle?  I mean just any of the deluded folks on the other forums we visit that are always telling me that.
(OH, you believe them like I believe them.. Not at all)  Of course there's a difference.
Good article, Picked up a couple of points,  Thanks.

Hmmm, I don't recall anyone on the most popular RV forums claiming there was no difference between starting and deep cycle batteries.  In fact, there is a contingent of battery bigots on RV.*** that will talk battery nuance for hours at the very mention of the subject.
 
Well hardly a week goes by someone does not start another battery thread... It may be I've been there longer than you but I know a couple of years ago I got hammered all the time for saying there was a difference.  And a good number of folks (myself included) posted links to pages that said there is.  Your link, by a battery manufacturer, Well they should know, shouldn't they?

It can be fun,  I mean to me, having grown up with flooded wet cells, and both six and 12 volt types. all this battery stuff is kind of basic.. I'm sure you are in the same class when it comes to batteries.

But you see some of these kids who flunked basic chemistry and .. Well....

(My college degree is in the sciences, and my trade cert is electronics).

(For this I got to tell cops where to go for 25 years (Dispatcher))
 
A few good point from reading it  Gary. Thanks again


Proper Application and Installation

Is the battery being used in the application for which it was designed? A standard automotive battery used in a recreation vehicle designed for a deep cycle battery is an obvious misapplication.

AGM batteries have lower internal resistance than similar flooded batteries, which means they will provide both faster high performance starts and faster recharge times.

The ?acid-starved? condition of AGM batteries protects the plates during deep discharges. AGM batteries typically last significantly longer than flooded starting batteries and excel for high current, high power applications and in extremely cold environments. They self-discharge at a lower rate than conventional batteries, making them ideal for seasonal applications where the battery is stored for part of the year.
 
Well. This whole battery thing is one of the things that has me really PO'ed at my local RV shop. There has certainly been quite a few discrepancies between the advise that they have been giving me, and the general consensus of you fine folk, here. When I needed a new house battery, they pushed me towards an interstate group 24 marine battery as the best choice. They never even suggested two golf cart batteries in series, which has almost 3 times the Ah capacity... When I asked specifically, after finding out about them here, they quickly dismissed it, saying something like - "well, with a parallel 12v bank, if one battery goes bad, at least you'll still have 12v... If one of the GC batteries goes bad, you'll only have 6v." Well, now I'm stuck with it for the short (2yr?) term.

I mean, I understand the convenience that having a local shop affords, but lets just say that I will only be using them for their convenience, and not their advise so much...


Mylo
 
Their advice about a failure is correct but not of any real significance. As long as the failed battery is still wired in, it is causing a problem whether it is 6v or 12v. No matter how you do it, once multiple batteries are wired together, they function as one big battery. So yes, if you have 12v batteries you can remove a weak or failing one and continue on, but that is a very slight advantage. That slight advantage is far outweighed by the greater capacity and superior reliability/longevity of the 6v GC batteries.

A pair of 6V GC batteries is about 32% great amp-hours than a pair of group 24 12v.  225 AH vs 170 AH.
 
If I were on the road and my 12 volt house band completly failed.. I'd jumper the emergency start solenoid (Very easy to do on my rig) and head for the nearest battery store.  On the road, the only 12 volt house systems in use are.. The fridge (normally) and power for the inverter (optional).

At a campground.. Though I am using the 12 volt system I have dual converters that between them can provide 225 percent of max house load.
 
Price/ performance usually is a trade off for deep cycle batteries. While a true deep cycle  6 or 12 volt will give you 40-60% more capacity it cost up to double as well. For those of us who boondock the higher capacity batteries are a must but if your normal use is to run out to a camp ground and plug in then the marine/RV batteries that most RV dealers use for cost reasons will probably suffice.
 
Jeff said:
Price/ performance usually is a trade off for deep cycle batteries. While a true deep cycle  6 or 12 volt will give you 40-60% more capacity it cost up to double as well. For those of us who boondock the higher capacity batteries are a must but if your normal use is to run out to a camp ground and plug in then the marine/RV batteries that most RV dealers use for cost reasons will probably suffice.

I do agree with you Jeff. I learned my lesson on this. Now with me boondocking most of the time i found out that my batteries would not hold up so I took a big jump to the AGM's. I did get a great price because of a friend. Thank God
 
I know that many, if not all hybrid cars use them. So I guess you could. but the cost would be a ton for sure. ou can look here for some for RV's  http://www.lithiumion-batteries.com/lithium-rv-deep-cycle.php. The cost for a 12V 150AH LITHIUM ION BATTERY is $1,699.99.
 
rvcalifornia said:
Is it possible to use lithium batteries instead, has anyone tried it

Yes but the comma the price tag discourages ...

There are, in fact Lithium batteries made specifically to replace common automotive sizes like Group 24, 27,29 and 31,, Someone linked to them up thread I think.

http://www.lithionicsbattery.com/rv.html

In case it was somewhere else.
 
I'm gonna hijack this thread for a question, since it seems like you battery guys are all here - my 5er is boondocked all summer in a partly shaded area near Lake Tahoe. I have a 45w solar panel setup from Harbor Freight to charge the batteries. I currently have 2 6v trojan golf cart batteries hooked up as a big 12v battery (batteries are about 3 years old). This keeps my lights working and heater working when I'm there on the weekends, but my propane fridge will often quit during the week.  When I check the battery power, it usually reads 12 to 12.5v when I arrive Saturday, and 11.5v when I get up Sunday morning after running the heater in 30 degree temps, before the sun starts shining on the solar panels.

A local RV shop suggested I replace the 2 6v batts with one 12v deep cycle battery, saying that the 12v will get a fuller charge from my small solar panels. The batteries start out the summer with a full charge, then the 5er doesn't get plugged in for 5 or 6 months, relying solely on the solar panels. The shop said it's likely that the 6v batteries never get a full charge, and the low charge could fluctuate enough to shut off my fridge.

What say you, my battery expert friends?
 
IMHO I would stay with the 6 volt battery bank because you have a larger amp hour rating. Maybe you should have the batteries check to make sure they are good. If they are, I would increase your solar charger to at least two panels minimum. To be honest, 45 watts isn't that much. I have 900 on my coach so I can stay ahead of power demand in the fall and spring months when the sun isn't at its highest. Even with the 900 watts, I will never see that. The most I have seen so far was 780.

And as you might know, there are some people on this Forum that are real smart and will most likely share a better idea or ideas with you than me. ;D
 
I'm not one of the smart ones that Terry was referring to, but I think it's a good bet that your small solar panel has deteriorated over the years, as much or more, than your batteries have.  The advice that you were given, to change to a single 12v battery, makes no sense to me.  You might see a small improvement simply because the 12v battery would be new, and the 6v's are three years old, but I doubt it.  Simply an opinion....

As suggested, more solar power would be my first consideration.  I'm actually quite surprised that you are getting the performance, from your set-up, that you are.  Congratulations. 
 
Simply put, the shop is full of crap. You DO have a 12v battery - it just happens to be in two pieces instead of one.  There is no difference in chargability between the two.

45 watts is not a lot of charging (about 3 amps) and you get that only in full sun, and even a tiny shadow across part of it, e.g. one small tree limb,  can reduce that to near zero.
 
So a big 12v (made up of 2 6v batteries) doesn't take any more to charge it then a regular 12v deep cycle battery?

I just got an 80w solar panel with a used camper I bought, so I'll be using that along with the 45w Harbor Freight setup next summer, and see if that helps.

Thanks for the advice.
 
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