12V Battery Identification

[Oonrahnjay]

    I have been offered 10 of these batteries at ~$18 each.   They are from a cell tower - rated 8 years, in service for approx. 2 years.  I don't know how long they've been stored but I'm charging them and will check that they take/hold a charge before I buy them.   Each one weighs about 57 pounds and they're rated at 77AH - Deep Discharge.
   On the battery is the legend "Non-Spillable Battery", the charge rate is shown as "Float Charge - 13.5V - 13.8V".

   Are these sealed wet batteries, or AGMs???



   Thanks!!!   BH

[Geom]

This might help,

http://www.interstatebatteries.com/powercare/stationary/pdf/HighmaxrateUPS.pdf

[mung]

What is your plan for them? 

[Geom]

These look like datacenter ups batteries. Those are usually pretty solid batteries with a good long shelf-life; assuming they're kept charged. I'm not sure how well they would do constantly discharged/recharged as would be the the case in an RV setup, since they usually just sit there at full charge until the datacenter experiences a power outage.

I can't imagine why they wouldn't work great though, they're just AGM batteries with deep-discharge capability.

[mung]

For house batteries they might not be the best.  UPS batteries are designed to stay charged, take a deep discharge, then a slow recharge.  Where as your typical deep cycle battery is meant to be run down to different levels and fairly rapidly recharged over and over again.  Also the weight to power ratio seems very high.  Two 6v golf cart batteries is going to give you around 245 ah at around 62lbs each, or 124lbs total, to get the close to the same run time you are looking at 3 of those at 171lbs total. 

The price is right, but the application might not be. 

[Oonrahnjay]

For house batteries they might not be the best.  UPS batteries are designed to stay charged, take a deep discharge, then a slow recharge.  Where as your typical deep cycle battery is meant to be run down to different levels and fairly rapidly recharged over and over again.  Also the weight to power ratio seems very high.  Two 6v golf cart batteries is going to give you around 245 ah at around 62lbs each, or 124lbs total, to get the close to the same run time you are looking at 3 of those at 171lbs total. 

The price is right, but the application might not be. 

     Thanks, I was hoping for a good deal.  Gotta think about this one. 

     First, I've put about half of them on the charger - they're pretty "hot" already, couldn't have been stored too long and they take a charge very well.  They all seem to charge in about the same time. 

     I am a bit concerned about your reply, Vern.  If they're not really going to stand up to RV use well, then that's a concern.  But I can get them for scrap value, if they last me 6 months and I scrap them, I have 6 months free.

      But I'm in a special case here.  I installed my generator and inverter about three years ago; at that time, I wasn't sure exactly what batteries I wanted but a friend of mine had two 8-D's from his boat that he was going to recycle.  They're marine, so halfway between "starter" and "deep cycle" and they were a little old and he was going to change them out just to be safe.  He didn't need them for cores and he told me "oh, you can have them if you'll take them out of my way in the shop".  They didn't seem to be the best-batteries-in-the-world but they did OK and they allowed me to get a feel for the setup of my inverter/charger and they worked OK.   Then about a year ago, a maintenance man at the storage yard decided to unplug my shore cord so that he could mow the grass in my storage area.  I was away for vacation and before I got home, I got a call from a friend in Quebec inviting me to come visit and see their new house ("new" - built in 1680) and then I got a call offering a couple of days work, it took longer than planned to get home.  Of course, the guy didn't plug my shore cord back in so it sat there with the fridge running and other parasitic draws for about a month.   I did everything I could but those batteries were fried - and I mean fried.  They're just OK for ballast as my bus is plugged in but otherwise there's almost no power in them.  So, I'm looking for another "temp" set of batts to replace them until I can.
      I don't think I want more 8-Ds as house batteries so I can scrap these (almost $0.50 a pound here) and run these for a while.  Then, when the stock market recovers and I'm further away from some home repair and medical expenses, I can go to "golf cart batteries".  Oh, and I don't think I mentioned that these UPS batteries are just about a perfect fit for my battery box (the 8-Ds, not so much).

     So, unless someone tells me that there's something about these UPS batteries that will damage my system, I think I'm going to go with them.  They may not be great and may be low-power-for-weight, but they're almost free.

     With all this in mind, should I go for them?

[bevans6]

Batteries get optimized for a certain type of usage, be that UPS, deep cycle or starting, but that doesn't mean they can't do anything else.  A deep cycle battery and a UPS battery share an awful lot in common, and I personally wouldn't hesitate to grab those batteries at $18 a pop.  That's about 20% of what the equivalent wet cell battery would cost at walco, and the batteries will probably perform a lot better anyway.  Just try to make sure you can charge them and maintain them per their specification sheet.

As you say that is virtually the trade in price, so when you get rid of them you may well get all your money back anyway.

Brian

[Oonrahnjay]

Batteries get optimized for a certain type of usage, be that UPS, deep cycle or starting, but that doesn't mean they can't do anything else.  A deep cycle battery and a UPS battery share an awful lot in common, and I personally wouldn't hesitate to grab those batteries at $18 a pop.  That's about 20% of what the equivalent wet cell battery would cost at walco, and the batteries will probably perform a lot better anyway.  Just try to make sure you can charge them and maintain them per their specification sheet.

As you say that is virtually the trade in price, so when you get rid of them you may well get all your money back anyway.

Brian 

      Thanks, Brian.  That's pretty much what I was hoping for!   Best,   BH

[Geom]

I've run ups batteries for continued deep discharge cycles and they performed well enough. They were not as large as these, but same principal. I also didn't discharge them to empty. That's not good for any lead based battery (or any battery for that matter) anyway.

I agree with Brian, they may not be "ideal" as a house battery, but for basically scrap they should be quite sufficient. It is true that they are not designed for continued discharge, but they are deep-cycle capable batts that should be sufficient and would be more appropriate than say a start battery would be. And as long as you've got a good charger/maintainer on them they should be fine.  

If you were buying with "new" money I'd look elsewhere, but at the price these seem to be offered at, I'd snag them up without hesitation.
They should behave and perform like any other battery, as far as any potential for damage, keeping voltage parallel/series connectivity the same.

[mung]

Yes at that price if they only last a year it isn't that big of a deal.  Now, just make sure you have the right type of charger.  That will kill them faster than anything else.  Not just how they are charged, but how they are maintained.  Charge them at the wrong rate and they will be toast, if the maintenance or trickle charge rate isn't right, they will be toast. 

Honestly, the best "charger" for them would be a UPS.

[bevans6]

FWIW, and I know everyone doesn't have one, but the charger in my Magnum 4024 can be dialed in to suit about any battery ever made.  Computers are definitely good for something!

Brian

[Geom]

FWIW, and I know everyone doesn't have one, but the charger in my Magnum 4024 can be dialed in to suit about any battery ever made.  Computers are definitely good for something!

Brian

Same here for the Victron I'm using. I think just about any good quality inverter/charger should be able to provide the needed float level/charge; although you might need to play with your specific charger to tune in the right battery type. Mine lets me choose from wet, AGM, etc as presets, or I can customize the set-points manually (for lithium for example).

[Oonrahnjay]

Same here for the Victron I'm using.

    And same for my Outback. 

[eagle19952]

We might do well to review this thread:
http://www.busconversions.com/bbs/index.php?topic=24105.msg264652#msg264652