Gel batteries

[Vintage465]

Hi.
I have acquired two used 135ah 12v gel batteries. They are 5”x18”. They were back batteries that were changed out after a years service. I think they really have no usage. My question is how will they work along side my existing 6v set up? Is there any specific charging instructions for this type batteries? If I can get them squeezed in somewhere on my rig should I hve their charging and usage separate from the 6v setup?

Thanks

[Vintage465]

landyacht318 wrote:
Which charger did you use on the 2 amp setting?

My friend has a 2/10 amp schumacher that on the 2 amp setting will not go above 13.7v, and was at less than 0.62 amps on a battery I knew was nowhere near fully charged.

Irritated, I put my meanwell power supply on this battery set it at 14.7v and the battery was taking over 16 amps less than a minute after taking it off the 2/10 amp schumacher, and the ~100Ah battery wound up accepting 33 more AH, according to the attmeter on my Meanwell output, before amps tapered to a low enough level where they could be considered fully charged.

Voltage fresh off the charger is basically meaningless, unless it instantly drops to 12v or below, indicating a shorted cell.

Do not trust any charger to do what it says it will do. Verify. With an Ammeter in addition to a voltmeter.

Put somethng like this inbetween charger and battery. DO NOT trust any charger to do what it says it will do without verifying.

inline wattmeter

Most people with absolute faith in their whizz bang smart charger purchase will be extremely let down if they actually knew and understood what was NOT going on, which should.

The charger I have is also a 10/2 amp charger. On the 10A setting it has an automatic shut down when the battery is fully charged......or when the charger thinks the battery is fully charged. Seems like on the 2a setting you can trickle it up to a higher voltage. I suppose if I had a charger that you could force feed a battery it would probably help "clean" these up. I'm kind of curious to see how they settle out. Then I have to see if I can find a place to put these guys!

[landyacht318]

Which charger did you use on the 2 amp setting?

My friend has a 2/10 amp schumacher that on the 2 amp setting will not go above 13.7v, and was at less than 0.62 amps on a battery I knew was nowhere near fully charged.

Irritated, I put my meanwell power supply on this battery set it at 14.7v and the battery was taking over 16 amps less than a minute after taking it off the 2/10 amp schumacher, and the ~100Ah battery wound up accepting 33 more AH, according to the attmeter on my Meanwell output, before amps tapered to a low enough level where they could be considered fully charged.

Voltage fresh off the charger is basically meaningless, unless it instantly drops to 12v or below, indicating a shorted cell.

Do not trust any charger to do what it says it will do. Verify. With an Ammeter in addition to a voltmeter.

Put somethng like this inbetween charger and battery. DO NOT trust any charger to do what it says it will do without verifying.

inline wattmeter

Most people with absolute faith in their whizz bang smart charger purchase will be extremely let down if they actually knew and understood what was NOT going on, which should.

[Vintage465]

So I've charged one of them up full for two days @ 2amps. It was 13.72 volts after I unhooked it and move the charger over to the other one. I'll what it settles too.

[2oldman]

Ya, nobody would mount them upside down, not even telecoms.

[landyacht318]

Yes, we've all seen how most AGMS say they can be mounted in any position but for upside down. This no doubt makes their marketers have a wet dream.

BUt the tellycom jars are much thinner, taller, and longer, and likely would never have any reason to be mounted in any orientation but right side up, and stacked side to side for the shortest possible interconnects.

This thin tall wide plate orientation might not enjoy being bounced around on their sides, if they were ever installed in such a manner.

So anybody ever see any tellycom battery documentation say that they can indeed be mounted in any orientation but for upside down?

[BFL13]

2oldman wrote:

landyacht318 wrote:
I wonder about tellycomm AGM's, and whether they are actually OK to orient on their sides.

AGMs can run in any position.

Mine say any position except upside down.

[Vintage465]

Yesterday I put one of them on a charger to see what the actual condition of the battery is. It would seem that they are nearly fully charged as the 10a charger started to cycle on and off. I backed it down to the the 2a setting to let it fully charge. Then I'll do the next one, unhook them and see what they settle at.

[2oldman]

landyacht318 wrote:
I wonder about tellycomm AGM's, and whether they are actually OK to orient on their sides.

AGMs can run in any position.

[Vintage465]

landyacht318 wrote:
I wonder about tellycomm AGM's, and whether they are actually OK to orient on their sides.

Seem like in dedicated telecom usage, there would be absolutely no reason to ever use them on their sides, and perhaps they are not designed to be tolerant of long term being on their sides, subject to road and engine vibrations.

I'm not sure what you mean by orienting them on their sides? Are you speaking of laying them over "flat"? I only intend on them being in the upright position.

[westend]

A guy could do some further research on the characteristics of those Marathon batteries but they sure seem like a good battery. Free batteries can't be beat.
Since they are AGM batteries, you can locate them inside, close to furnace or near to the axles.

FWIW, I have two banks of different batteries, 2 X 6V GC2 and three AGM telecom batteries. I am able to switch either bank to either 12V distribution and the converter, to the inverter, or from the solar charge controller. The AGM batteries I have will take the same higher solar charge voltages that the 6V's need. I've had the two banks parallelled for a number of years. All of the batteries are inside my trailer, the 6V's in a vented box and the AGM's on the other side of the trailer, both near the axles.

[landyacht318]

I wonder about tellycomm AGM's, and whether they are actually OK to orient on their sides.

Seem like in dedicated telecom usage, there would be absolutely no reason to ever use them on their sides, and perhaps they are not designed to be tolerant of long term being on their sides, subject to road and engine vibrations.

[Vintage465]

BFL13 wrote:
Depends on the individual RV's layout/floor-plan for being able to do this, but I have a mix of AGMs and Floodeds. Key is that the AGMs can be inside the rig, but not the Floodeds. I split the batteries into two different banks.

The AGMs in a bank just do the big inverter, which does "whole house" for all 120v items I run (not the air conditioner, fridge, and WH of course) so that takes care of a big bunch of 12v.

The "normal" RV 12v stuff (furnace, lights, fans, etc ) are run from the Flooded bank as a separate event.

I keep track of how far down each bank is getting and recharge as necessary using the charging specs for the AGMs on them, and the charging specs on the Floodeds for them. I have an adjustable voltage charger so that is no problem. (PowerMax ADJ type)

In addition I have two separate solar arrays on the roof, and each has its own controller, which has the right charging specs for each type of bank.

At home, I keep each bank at its own Float voltage with two different chargers for that.

What I really like about all that, is the regular 12v Flooded batts can be run down farther so I don't have to care about getting too close to where the inverter will alarm off when I run the microwave or whatever. The inverter having its own battery bank means freedom compared with before when I had it on the same bank with everything else 12v.

That's pretty much what I've been considering doing, but with one solar charging set-up that I can select which bank to charge. I would like to be able to run my 12v/propane forced air unit off a dedicated bank so if the voltage gets low for one reason or another the rest of the trailer is not affected. I like the water pump and C-paps to work steadily even if the furnace is struggling. These 155ah batteries could make that happen sooner than later.............one reason is the cost......Zero $'s. And since they're sealed, they can really go anywhere. All in the thinking stages now.

[Boon_Docker]

beemerphile1 wrote:

Vintage465 wrote:
This is a pic of the data on the battery.

Just pointing out, deep cycle batteries in RV use generally the ah rating is at 20 hours. The rating on the label is at 8 hours. Apples and oranges.

Apples and Apples

The rate stated (155 AH @ 8 hours) is equivalent to approx 220 AH @ the 20 hour rate.

[BFL13]

Depends on the individual RV's layout/floor-plan for being able to do this, but I have a mix of AGMs and Floodeds. Key is that the AGMs can be inside the rig, but not the Floodeds. I split the batteries into two different banks.

The AGMs in a bank just do the big inverter, which does "whole house" for all 120v items I run (not the air conditioner, fridge, and WH of course) so that takes care of a big bunch of 12v.

The "normal" RV 12v stuff (furnace, lights, fans, etc ) are run from the Flooded bank as a separate event.

I keep track of how far down each bank is getting and recharge as necessary using the charging specs for the AGMs on them, and the charging specs on the Floodeds for them. I have an adjustable voltage charger so that is no problem. (PowerMax ADJ type)

In addition I have two separate solar arrays on the roof, and each has its own controller, which has the right charging specs for each type of bank.

At home, I keep each bank at its own Float voltage with two different chargers for that.

What I really like about all that, is the regular 12v Flooded batts can be run down farther so I don't have to care about getting too close to where the inverter will alarm off when I run the microwave or whatever. The inverter having its own battery bank means freedom compared with before when I had it on the same bank with everything else 12v.