Battery choice

[buckland]

Wow Thanks for that (being a retired teacher I appreciate clear explanations) ... I follow what you are saying. It is definitely something I need to address before this trip. I will have the two batteries tested and see what they look like. Again thanks. I love learning up whenever I can get it through my thick head. As I type this it is snowing like crazy... a foot plus for a good ole Aprils joke on me. All I want to do is get into the camper and work but as they say ... Man plans ...God laughs.

 

[Casa Escarlata Robles Too]

My understanding for not mixing different batteries in parallel is if the older battery is 0.05 volts lower than the newer battery then the older battery will parasite the newer battery all the way to zero volts, a death spiral. Currant flows from high voltage to low, new battery to old. Batteries in series do not have this issue since the older lower 0.05 volts battery will just drop the combined batteries in series voltage by 0.05 volts. Even if the two batteries have the same voltage when the newer battery is first installed, the older battery voltage can still unexpectedly drop lower than the newer battery at some later date. Starting with two identical batteries reduces the chances of one battery parasiting the other battery but does not eliminate the chance of one battery voltage dropping below the other battery. Only series battery installation prevents parasiting. Batteries in series have the disadvantage of one battery cell failure in one battery killing the whole battery pack while batteries in parallel pack can be partially salvaged by using a volt meter to find the battery with the bad cell and switching to single battery operation until a new battery pack can be purchased.

I am not an expert, this is just my understanding.

Thanks for that lesson on batteries. Good to know stuff.
Frank

 

[iowahiker]

buckland, What did you teach? I spent one summer working as a carpenters assistant in southern Vermont near Emerald Lake SP. Exploring the Green Mountains was fun during my weekends.

We are planning to visit New England during the next few years, when is the best early season time to visit to avoid crowds, black flies, and bad weather?

 

[Vic Harder]

So, if you want to know what a "Stress test" is, this might help
"
After the batteries were conditioned, fully charged, and rested overnight at room temperature, we started the first round of our reserve capacity discharge test. The SAE J537 storage battery Reserve Capacity Test states in Sec 3.5, “Discharge the battery at 25A (+/- 0.1A). During the discharge, using any convenient method, maintain electrolyte temperature within the range of 75 F –90 F. End the discharge when the voltage across the battery terminals has fallen to the equivalent of 10.5V, noting the discharge duration in minutes.” When a VRLA battery’s voltage falls to 1.75V per cell (a 12V battery has six cells x 1.75V per cell = 10.5V) then its depth of discharge (DOD) is said to be 100 percent."

From http://www.practical-sailor.com/issues/32_3/features/Deep-Cycle-Battery-Test_5244-1.html

 

[buckland]

Iowahiker I taught Math and Science to middle and high school in Paraguay ( US Embassy), American School of London, Kobe Japan, (total 5 years) and then 21 years in Amherst Massachusetts, then was Apple tech school IT...got out after a year and went on to a masters in cabinetry... period furniture for the last 8 years... do now mostly antique furniture restoration and teach a bit in a woodworking school on math/geometry related things like volutes and furniture proportions.......So a hodge-podge of interesting low paid work!... I do love teaching ... but it is a hard job...not with the kids ... but the administration stuff...

 

[cwdtmmrs]

buckland..A masters in cabinetry,I'm impressed!

cwd

 

[adamxcl]

This made me stop and realize my current batteries are now 10 years old. They perform as good as ever though. The set of AGMs have been on solar year around, staying topped up. And they are used but I always seem to have more than enough power. Just finally replaced the engine battery at 9 years.

 

[Southpaw Surfer]

Having trouble locating the suggested battery replacement in this thread locally

VMAX MR127-100 Deep Cycle, High Performance AGM Battery
Hoping to take my Hawk out this weekend for her maiden voyage with her new family.

I located the model below and am curious if anyone here is familiar with this manufacturer and model. The battery store rep said it's the best on the market. Being that they had it in stock I'll take that with a grain of salt.

Lifeline GPL-27T
http://lifelinebatteries.com/wp-content/uploads/2015/12/GPL-27T.pdf
http://lifelinebatteries.com/products/marine-batteries/gpl-27t/

 

[ckent323]

Southpaw,

Contact them directly. They will ship to you for free as they did to me. They are in San Dimas, CA. I dealt with David Miller he was friendly and helpful.

Lifeline Batteries Inc.
292 E Arrow Highway
San Dimas, CA 91773
Mailing Address
PO Box 637
San Dimas, CA 91773
Phone: (909) 599-7816
Fax: (909) 599-0596
Hours of Operation:
Monday through Friday 7:30am to 4:00 pm Pacific Time

Craig

 

[Vic Harder]

The spec sheet on this battery confuses me... it lists CCA and deep discharge time. I didn't think that real deep discharge batteries cared about CCA?

 

[ckent323]

Vic,

It is curious that CCA is given but they say it is a deep cycle (vs a hybrid) and they provide the standard deep cycle battery rated capacity amp hours at 20 hr rate.

In small boat use batteries are often used as both starting and house batteries (as in my Dad's sailboat) so perhaps that is why CCA is listed.

From the e-marine site:

Lifeline GPL-27T AGM Deep Cycle Marine Battery is a high performance, high quality that has an Expected Cycle Life 1,000+ cycles to 50% DOD.

https://www.emarineinc.com/Lifeline-GPL-27T-AGM-Deep-Cycle-Battery-12V


That sure seems like a true deep cycle to me.

(I have two Lifeline GPL-4CT 6 V batteries in my camper)

They do have a good reputation.

 

[klahanie]

I located the model below and am curious if anyone here is familiar with this manufacturer and model. The battery store rep said it's the best on the market.

I have a pair of the next size up - 31 - have been using for ~ 8yrs. At the time I was looking I came to the conclusion that they were a premium battery.

Haven't re read all this thread so I'm unsure of the reference to "the suggested battery replacement". But fwiw. a few years later I bought a second set of much cheaper12V batteries, Kirkland Marine RV FLA type. These are used as my primary house bank with the Lifelines as an auxiliary bank.

Both sets work satisfactorily - as batteries.

 

[craig333]

For Vmax, look at amazon. https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=VMAX+MR127-100

 

[Vic Harder]

I think I would be misleading folks if I didn't say this: Marine batteries might be deep cycle, but they are NOT the ideal battery for your camper. Any battery that lists CCA is not ideal.

True solar batteries that are not designed for ANY high discharge (CCA) are what you want. Think golf cart batteries or batteries designed for slow steady daily full discharges.

I could be wrong though. Has to happen at least twice!

 

[Wallowa]

I think I would be misleading folks if I didn't say this: Marine batteries might be deep cycle, but they are NOT the ideal battery for your camper. Any battery that lists CCA is not ideal.

True solar batteries that are not designed for ANY high discharge (CCA) are what you want. Think golf cart batteries or batteries designed for slow steady daily full discharges.

I could be wrong though. Has to happen at least twice!

Vic et al,

Great discussion...but my electron challenged brain is a tad confused...what batteries do FWC use and why? And of course if there is a longer lived battery than what FWC uses that meets the solar/FWC needs I would love to have it singled out and described why it is superior...size/brand etc.

Thanks all for the input..

Phil

 

[Vic Harder]

Well, call me stupid.... before expounding more, I decided to do some more quick R&D. And I can't prove the statements I made above! What I did was look at the Rolls battery www site. They have a selector for marine, solar, motive, etc. I picked a 210 AH 6V battery from each and compared them:

Motive - http://www.rollsbattery.com/wp-content/uploads/batteries/6FS210.pdf
Solar - http://www.rollsbattery.com/wp-content/uploads/batteries/S-270.pdf
Marine - http://www.rollsbattery.com/wp-content/uploads/batteries/EHW210.pdf

And, guess what... they are identical.

What does this prove? I'm not sure. Looking to the other clever folks here jumping on an educating us all... and mostly me.

 

[PaulT]

Well, call me stupid.... before expounding more, I decided to do some more quick R&D. And I can't prove the statements I made above! What I did was look at the Rolls battery www site. They have a selector for marine, solar, motive, etc. I picked a 210 AH 6V battery from each and compared them:

--snip--

And, guess what... they are identical.

What does this prove? I'm not sure. Looking to the other clever folks here jumping on an educating us all... and mostly me.

The marine doesn't claim to be dual purpose. Perhaps a clue as motive & solar are quite similar. Marine, in this case, may mean house battery rather than dual purpose. Just a SWAG. ¯\_(ツ)_/¯

Paul

 

[ckent323]

Vic,

There are a couple of things in the construction of a deep cycle battery that for us are important.

First is plate thickness. It is my understanding that the Concord Lifeline GPL batteries have a 0.110 plate thickness (I have read third party claims about that but have not found the manufacturer data to verify that) which is the same thickness as the Rolls models you posted.

I found the following info: Automotive batteries typically have plates about .040" (4/100") thick, while forklift batteries may have plates more than 1/4" (.265" for example in larger Rolls-Surrette) thick - almost 7 times as thick as auto batteries. The typical golf cart will have plates that are around .07 to .11" thick. The Concorde AGM's are .115", The Rolls-Surrette L-16 type (CH460) is .150", and the US Battery and Trojan L-16 types are .090". The Crown L-16HC size has .22" thick plates. While plate thickness is not the only factor in how many deep cycles a battery can take before it dies, it is the most important one.

that was obtained from this site:
https://sites.google.com/site/etmbatterydivision/deep-cycle-batteries-faq/battery-plate-thickness

The second and most important is the number of deep cycles the battery can take fore it fails (which is related to the plate thickness).

The Lifeline GPL is rated at 1000 cycles at 50% depth of discharge which appears to be about the same number as the Rolls models you provided links to.

The lifeline manual is here:
http://lifelinebatteries.com/wp-content/uploads/2015/12/6-0101-Rev-E-Lifeline-Technical-Manual.pdf


Good discussion

Craig

 

[Vic Harder]

This is great info Craig! I was surprised that the different applications Rolls listed all had the same model battery in the backend. Your info requires the potential buyer to dig pretty deep to find info about their battery, info that may not be listed anywhere. I was hoping that a simple lable like "Marine" would easily dismiss them from our consideration.

No such luck!

I have previously said somewhere on this forum that a good battery will have a detailed spec sheet and charging details. I guess that is even more true now for me. Thanks for adding the info about plate thickness and the comparison data.

I laugh about the number of cycles and battery life. My 222AH bank has only seen 1 cycle in 42 camping nights. And that was because I purposely disconnected all charging sources to see how long it would take to drain the batteries. So, my batteries should last forever!

There has to be a "shelf" life or some other way of estimating how long these will last.

Thanks again for all this great data Craig.

 

[ckent323]

Vic,

It seems that a properly maintained battery (low DOD, kept at float etc) will lose as much as 2% to 4% capacity per year due to various aging mechanisms (gas permeation, temperature effects, etc). A lead acid battery is considered unusable once its capacity has dropped to 80%. Assuming 2% a year suggests 10 years and 4% a year suggest 5 years.

I have read estimates claiming 10 - 20 years for the very thick (0.220") plate fork lift batteries, a somewhat shorter time around 10 years or more for golf cart type (0.110" thick plate) deep cycle batteries (similar to what we are using in our campers) and around 5 years for thin plate starting (vehicle) batteries.

Here is one helpful link I found on a lifetime study:

http://www.power-thru.com/documents/The%20Truth%20About%20Batteries%20-%20POWERTHRU%20White%20Paper.pdf

I have added the links from my two most recent posts to this thread to the "Ultimate Battery Thread" here:

http://www.wanderthewest.com/forum/topic/15574-ultimate-battery-thread/

Craig