Advice please on used Centennial DC8D batteries

[sassypickins]

I am considering buying one of two used batteries to use as my first house battery to use and probably abuse until I feel ready to graduate to new, insanely expensive ones.

They are 12v Centennial DC8D's and though I could not find this particular one listed, with 1500 cca it is likely around 240 -250 Ah, I think.  Big, around 20 x 11 x 8.
[img=600x371]http://images.craigslist.org/00q0q_e8rZaNBtHHI_600x450.jpg[/img]

I asked the seller some questions, then called Centennial with the imprinted date codes.  One battery was manufactured Feb '13 and the other Mar '13.  The current seller purchased this spring from someone who pulled them from an RV he was converting to a food truck.  He never used either for his off-grid plans.  He said yes, they were low on water, but not alarmingly so, said levels were all about the same.  He filled with distilled water and charged.  He doesn't remember what the charge meter read.  He said he did not have them 'stress tested' or 'special cycled such as desulfinated'.  He expects they are discharged by now.

I called a battery place here and was told if I could bring them in he would put a load on each, do the hydrometer test for state of charge, and some other test with a gizmo I can't remember the name of now.

If I can get the guy to let me do that, or get him to do it, what should the tests show in order for me to pay $80 for one of these brutes? 

Did his letting them sit untended for 6 months ruin them and I should just forget it?

Sassy

 

[ahh_me2]

Here is a link from Trojan giving some important info on batteries, it could be a good read for you even if you don't understand a lot of it.

http://www.trojanbattery.com/tech-support/battery-maintenance/

I would definitely have them tested because if they have been left dis-charged and low on water for a while, it's not very good.
If the water was so low the plates were exposed, they could be oxidized which severely reduces their capacity.

 

[29chico]

I am considering buying one of two used batteries to use as my first house battery to use and probably abuse until I feel ready to graduate to new, insanely expensive ones.

They are 12v Centennial DC8D's and though I could not find this particular one listed, with 1500 cca it is likely around 240 -250 Ah, I think.  Big, around 20 x 11 x 8.
[img=600x371]http://images.craigslist.org/00q0q_e8rZaNBtHHI_600x450.jpg[/img]

I asked the seller some questions, then called Centennial with the imprinted date codes.  One battery was manufactured Feb '13 and the other Mar '13.  The current seller purchased this spring from someone who pulled them from an RV he was converting to a food truck.  He never used either for his off-grid plans.  He said yes, they were low on water, but not alarmingly so, said levels were all about the same.  He filled with distilled water and charged.  He doesn't remember what the charge meter read.  He said he did not have them 'stress tested' or 'special cycled such as desulfinated'.  He expects they are discharged by now.

I called a battery place here and was told if I could bring them in he would put a load on each, do the hydrometer test for state of charge, and some other test with a gizmo I can't remember the name of now.

If I can get the guy to let me do that, or get him to do it, what should the tests show in order for me to pay $80 for one of these brutes? 

Did his letting them sit untended for 6 months ruin them and I should just forget it?

Sassy

If the seller gave them to me I would recycle them at a place that pays $'s by the pound and put the cash towards the highest capacity true deep cycle flooded battery that I could afford.

Way too many unknown variables to consider forking out the hard earned.

 

[akrvbob]

The biggest thing to remember is they weigh 120 pounds each. How are you going to handle them? For that reason alone I'm not a fan of the 8d, even if they are brand new.

If it were me I'd get the biggest Walmart Marine battery in stock and learn on it for about $100. They have a very good warranty and it may end up being cheaper.
Bob

 

[WheelEstate USA]

X2 on Bob's suggestion. 
Been using Wally's big one for a year and it's as happy as a new one.

 

[highdesertranger]

x3 on Bob's 2 cents. highdesertranger

 

[SternWake]

A new Healthy 8d will have about 230 AH capacity

MaineSail made a claim somewhere that 8ds were all just starting batteries with  thin plates, not even the slightly thicker plates of a marine battery or the true thick plates of a deep cycle golf cart battery.

Even with an Impedence tester, and a carbon pile load tester, and good specific gravity measured by the hydrometer, one can only guess at its actual capacity.

A true 20 hour capacity test is the only real way to know the remaining capacity of a battery, but doing a real 20 hour test is a huge effort, and abusive to the battery.

While the tools above can definitively say a battery is weak, they cannot definitively say the battery still has 80% or more of its original capacity to give.

Used batteries are always a crapshoot, and more so when their previous care is unknown, and the previous owner was possibly  devoid of the knowledge about what a battery requires to maintain maximum capacity.

So one of these 8d's could certainly give you 80$ worth of cycles, or it might not.

 

[jimindenver]

He gave them to you? Time for some testing.

Get them charged up well. This could take days with your normal 2/12/50 charger. Once you have them charged up let them sit for a day and see what their voltage is. It should be 12.6 or higher.

Next if you have a hydrometer check the cells. You are looking for one that is lower than the rest. Even if on is low it may be ok still with equalization.

Last is a load test. I hooked up a volt meter and watched as I braked a 100a RC airplane starter to see if the voltage took a nose dive. You could possible do the same with jumper cables and your van.

Now honestly they have been sitting low on water and under charged, that's not good. I love 8-Ds for their ability to literally just puke up the power when you apply a huge load to them. Many are not deep cycle and you have to watch the deep cycling. Other wise they are a lot of power.

The last 8-D I recycled went for 20 cents a pound.

 

[sassypickins]

Ok, MANY thanks, guys. I've read battery 101 til my brain fried and forgot it all, but you have reminded me why I've not bought used batteries. I will feel better with a new battery and a warranty, and I have finally made a decision to get flooded and do the maintenance. They will be in a vented box right inside my side door, easy to get to. I will be a hydrometer guru. I will need a guru hat.

I knew it would indeed be a crapshoot to buy them used. I did not know how long a true test would take or how taxing, so thanks, SW and Jim. (Jim, these weren't given to me, they're up for sale @ $80 each.)

Jay, what did you buy? I'm finding only AGM's online at Wally's that have the Ah I want and they want like $230 or so. There are local sources here for T105's for about $150-160 including core fee since I don't have an exchange.

I want to ask for help about other components of this little house system. Should I start a new post and list what I think I know? Uh-oh, there's trouble already. I know it's been said and done a zillion times but I am having trouble recapturing it from elsewhere in a way that I can list for myself 1, 2, 3...

Sassy

 

[WheelEstate USA]

Sassy...The one I got is the DC29/122Ah. It has been working well with a 100W panel, but just put a second panel online the other day.
We have been able to watch DVDs nightly without dropping past 12.5V.
Its a good battery for the bucks.

 

[ahh_me2]

Hey, it can be hard to pick out what to buy for batteries, most people don't understand the technical aspects of it and become battery murderers, lol,
over time many will hopefully adapt and find something that does kinda work for them.

As much as this subject has been beaten to death, I think it is still a worthwhile topic to post on in a new thread as there are always people looking to have it explained a different way until they get it.

Not everyone learns the same way, and unless people are actively looking for a battery for their particular application, chances are they don't really read/understand the posts on the subject.

They say we learn through repetition, and so in my opinion, the more we can repeat knowledgeable threads on battery choices, the more people will learn and quicker too!

People are quick to say to say things like" search the forums", but that doesn't always work for an individual.

Like you say, you need it presented in such a way that you can finally figure out and understand the 1-2-3's

I'm sure many people would benefit from a new thread/discussion on the matter.

 

[SternWake]

If you need ~ 230 AH of capacity, 6v golf carts batts in series from Sam's or Costco will give much better service than a pair of group 27 or 29 or 31 marine batteries in parallel, and perhaps cost less too.

If you have the height available for using GC batteries, it will be worth the effort to get 6v GC's as they are actually made to be a deep cycle battery.

Group 27/29/31's are all dual purpose marine batteries with plate thickness half that of a GC battery/  GC's should last 2x the amount of cycles in the same discharge/charge regimen.

GC batteries are easier to fully recharge, and are much more likely to recover from abuse, such as a slow 100% discharge.

A single 12v  flooded marine battery is good, when one only needs 100 to 130 AH of capacity total, but step up to 230+AH and the 6v  GC battery is much better bang for the buck, initially, and long term.

The is no reason tha 6v GC batteries cannot be learner batteries, when one requires 230AH of capacity.

 

[sassypickins]

Yes, thanks, SW, if I'm going w/new I want 2-6v golf cart full-on deep cycle, for those reasons. Digging into the cash stash. My van plan included 12 3/4" height under bed #2 in case I didn't go w/AGM's that could be laid on their sides, so I should be good to go w/flooded.

I will start a new thread about what I need to satisfy my wants, but in any case, I will make the effort to treat my learner batteries like I want the relationship to flourish.

 

[Sabatical]

Sassypickins, are you going to make it to the RTR? That would be a great place to see many different setups and have face to face conversations with folks about the components. I find it much easier to learn when there is a visual component.

 

[jimindenver]

At $80 each and with known issue, I wouldn't touch them. As cores they are worth half that much.

Really you want something that's not fussy about being charged and can handle some abuse. A new pair of 6 volts would do well as long as you are not looking for the long term, heavy loads like a microwave. They also should not cost much more new than the 8-Ds did used.

I'd enjoy a battery thread but I am not much of a "this is good, that is bad" kind of person. Each has pros and cons that should be explored before balancing them against your needs and ability to take care of.

 

[sassypickins]

@Sabatical ~ Yes, I plan to be at RTR. I want to bring my supplies and get some help there. I am a hands-on learner, too.
@Jimindenver ~ I agree and did not buy the used battery. I am picking up two new T-105's. Tried and true and I'll have confidence in them.

Ok, I am going to start a new thread about my next steps and will greatly appreciate help. I can tell from your various threads and posts here you all know your stuff.

Thank you!

Sassy

 

[29chico]

If you can get some of the T105-RE's they are touted as being even harder to damage than the standard ones.
They weigh more, 5 pounds more each than the standard T105's, so they likely have more lead in them.

 

[sassypickins]

@29chico ~ Thanks! I did not even know about those. I called and revised my order. For some reason there was no core charge with these, so though the battery cost was more, the overall extra was only $6 each, but the warranty doubled!

Here's a blurb about them from the Trojan website:

"Premium batteries are optimized for Renewable Energy applications which are operate under challenging conditions such as fluctuating or extreme temperatures, remote locations and the intermittent nature of solar and wind power generation.

Designed with a 10-year battery life, Trojan Battery’s Premium line of flooded, deep-cycle batteries is specifically engineered to withstand the rigorous conditions of renewable energy applications. Our product strategy is focused on one simple objective – manufacture the highest quality battery available in the industry, which is why our Premium line is tested to IEC standards.

The Premium Line features:

Alpha Plus® Paste with T2 Technology™ which optimizes porosity development in the active material enabling the active material to be used more effectively. This results in sustained battery performance over a longer period of time.
DuraGrid™ Design provides a thick grid structure that resists corrosion, and when combined with the Alpha Plus Paste with T2 technology, increases overall battery life.
Maxguard® XL Separator is exclusively available in Trojan’s Premium and Industrial lines. It features a wide-channel design which increases acid flow for optimum battery performance, and provides even greater resistance to stratification, a typical mode of failure in batteries used in renewable energy systems.
The Polyon™ container is Trojan’s ultra-rugged case design which protects against damage caused by harsh environmental conditions, such as moisture and dirt buildup, and safeguards against potential acid leaks."

Thank you again, 29chico.

Sassy

 

[akrvbob]

If you can get some of the T105-RE's they are touted as being even harder to damage than the standard ones.
They weigh more, 5 pounds more each than the standard T105's, so they likely have more lead in them.

Trojan doesn't just claim they are better, they back it up with a longer warranty. The warranty alone is probably worth the extra money.
Bob