Gel batteries

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.

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.

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.

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.

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.

Vintage465 wrote:
Yes, they are sealed lead acid as I noted in a reply to my post above.

AGM and gel are both sealed lead acid. They differ in the way that the acid is held in suspension.

SoundGuy wrote:

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

So what you have are AGM Batteries, not GEL.

Yes, they are sealed lead acid as I noted in a reply to my post above.

Vintage465 wrote:
Well, I'm finding out more about the batteries. They are Tellecom batteries, and are Sealed Lead Acid. I will load some photos of them in a bit. They are 116 pounds a piece!

Looks like AGM, not gel to me.

Sound advice, LY

The rest voltage decay is by far the most important value that cannot be mismatched. But the decay should be measured after 10-days rest after being fully charged.

There are significant differences between a UPS model and automotive style AGM battery. Thicker mats, a significant percentage of calcium in both the positive and negative plates, and intercell connectors that are much less massive.

How does a person reconcile the charge needs between AGM and 2-3/4ths % antimony? They don't. And holding an AGM above 14.4 volts temp compensated for hours on end repeatedly is not feasible.

The batteries are going to constantly feud. Hatfields & McCoys.

Best choice is to rid the flooded batteries and pair automotive AGM with the Telecomms.

Not good sense to damage batteries needlessly. Flooded will draw the Telecomm batteries down almost immediately after cessation of charge and I believe forum members remember what happens to AGM batteries that never get fully recharged. This is one example where reality trumps E=MC2. I've done it and have seen the effects. If someone tried to give me a battery bank half flooded and half AGM I would not parallel them on a bet. The degradation is neither slow not subtle.

Not a surprise, 9 times out of 10 a 'gel' battery turns out to be an AGM instead.

I'd bring both upto 14.5v until amps tapered ot about 0.8a each, then let them rest and observe voltage as it settles.

If they are close in resting voltage, I'd have less fear of running them in parallel, but I doubt i'd parallel them with flooded gc-2's during discharge, and would want to top charge them separately.

When fully charged and rested I'd put a relatively high load on each separately, and time and measure voltage held during that load. If one is maintaining 12.53 where the other is 12.34v after the same load for same duration, I'd not use them in parallel for any long term duration.

But the worst that happens is they simply do not last very long. Just don't expect their full capacity when everything is paralleled, discharged then charged together.

Start by fully charging them, letting them rest, and then observing OCV.