Opinions on these AGM batteries

oldmansax · April 10, 2010, 06:54:38 PM

Anybody know anything about these batteries?

http://greensboro.craigslist.org/boa/1681013463.html

I know they are UPS batteries and that using them for house batteries is not the best use but my bank is almost 15 years old and I need to do something. I have room for six of these if I get them. I have a Heart Freedom 20 12V inverter/charger.

Opinions? Comments? Insults?

TOM

belfert · April 10, 2010, 09:02:53 PM

I believe these are the same batteries I have in my bus. They seem to work pretty well, but I have had mine in only for one season.

One issue I had was they didn't like it when my inverter/charger was set to flooded. I talked to the manufacturer and they recommended using the gel setting on my charger. If your inverter/charger is new enough to have an AGM setting use that of course.

Lin · April 10, 2010, 11:26:56 PM

I have the same ones. They also were used on Craigslist. I have not put them to any serious test yet though. The manufacturer can give you the proper charge settings. I think the specs are on their website. If your charger is not adjustable, the gel setting may be okay, but you could find out what those settings are and see if the two are compatible. These batteries are designed for UPS system, power backup, and are therefore different than ones designed for our use, but given the price, they are worth the compromise with perfection.

oldmansax · April 11, 2010, 04:52:54 AM

I do have a gel setting on my charger and it is adjustable. The only thing I don't have is the temperature probe option that is available. Should I look into buy the probe?

TOM

RichardEntrekin · April 11, 2010, 08:00:23 AM

I don't know anything about those batteries. However. Gel batteries and AGM batteries are not the same technology. AGM batteries will not tolerate charger abuse like a standard battery.

If you are going to the expense of putting in AGM batteries, PLEASE have a charger that is designed for or has a setting for AGM batteries.

Or you will soon have junk for batteries. I can hook you up with someone who fried 6 8D AGM batteries at the tune of 600 each if you would like corroborating evidence.

TomC · April 11, 2010, 09:50:50 AM

Richard- I believe you have the charge abuse reversed-the Gel Cell is very sensitive to over charge abuse. With the AGM, as long as you don't over volt it, you can recharge them with just about as much amperage as you have available. I know when I had 2-8D standard flooded batteries, I could only charge them at 80 amps total. Now with the two 8D AGM batteries, I can charge them at the full 130 amp rating of the inverter. Good Luck, TomC

Zeroclearance · April 11, 2010, 11:57:19 AM

Brian, how many batteries are you running? Have you checked your resting voltages? Do you think that you have 136 amp hours per battery?

luvrbus · April 11, 2010, 12:31:05 PM

All the AGM batteries will accept the same charge rate as a regular flooded lead cell no special charger required and just like a flooded cell overcharging will destroy one, LifeLine does not warranty their batteries from over charging and I would recommend a probe plus AGM batteries don't like the AZ heat.lol

good luck

Lin · April 11, 2010, 01:39:58 PM

As mentioned, I have the same batteries. The Dynasty website has a down-loadable file for them. It says the charge voltage should be 14.4-14.8. The float voltage should be 13.5-13.8. I remember I did call the company and verified the figures. I have it written down on the inverter\charger, but don't remember them. There may be a limit on total charge amperage too. You can verify that. AGM are the best way to go. Aside from getting the charging right, they take care of themselves. The price offered is good.

belfert · April 11, 2010, 04:45:42 PM

Quote from: Zeroclearance on April 11, 2010, 11:57:19 AM
Brian, how many batteries are you running? Have you checked your resting voltages? Do you think that you have 136 amp hours per battery?

I am running 6 batteries in series and parallel. When fully charged the batteries will sit at 13.8 volts. I have no idea if I am getting the full amp hours or not.

scanzel · April 12, 2010, 04:03:31 AM

If you are going to pick up these batteries your self I would ask if it is ok if you bring a digital meter and meter each one before you by it. AGM batteries will usually keep their voltage up above 12 volts for long periods. If any are way below 12 v I would not accept them. I have 8 of them that I will be using and presently just chage them up occasionally to keep them up.

RichardEntrekin · April 12, 2010, 07:34:20 AM

Sorry for the late reply.

Yes I agree AGM batteries do allow for a big amperage charge just like flooded cell. Gel cells will not tolerate that. So AGM's will charge up more quickly resulting in less generator time.

The AGM's require a slightly lower maintenance voltage to prevent damage than a flooded cell. The need for a specific charge algorithm for AGMs is driven by the maintenance charging and not the initial charge.