AGM Batteries Which one

Sand Man you say Remco have you any idea what no Batt just remembering it is to run 2 fridge's and is 80 amp enough.cheer's GREENDOG

Now we are comparing two different ends of the spectrum of battery specs and technology here.

Get the Remco :-))

Mainey . . .

Greendog,

The 80Ah is "enough" to run two fridges. More importantly though is how long you expect to run the fridges on the battery before it will need charged.

Depending on the combined current draw of the fridges, you will probably need to charge the battery each day by some method or other.

I run one 40 litre fridge which has a maximum current draw of 2.7 amps, but this is not constant. I currently use one 40 watt solar panel connected to my 75Ah Thumper battery system. From my current experience, the solar panel puts back in daylight hours approximately what is taken out by the fridge over a 24 hour period, but I also have a 30 amp in-car charger to fall back on, plus the 80Ah auxiliary battery as well.

Greendog,
I've been running a 100AH Remco in the rear of the vehicle for almost 2 years mainly for a 40L fridge and fluro. It replaced an Optima 55AH which didn't cycle long enough without recharging. The Remco was a bit cheaper than the Full River. No dramas with it.

If I'm not mistaken Remco is a gel battery. Different from an AGM. I had a remco 100ah that only lasted me 10 months and 3 uses in that time. It wouldn't hold a charge after that, even though I kept charging it with my dual battery isolator.

Maybe the remco isn't a dud like i thought. Maybe I was doing something wrong?

Manufacturer : REMCO
Model - Type : VRLA Lead Acid RM12-00 (AGM Deep Cycle) Battery is SULFURIC ACID (not gel)

Mainey . . .

I have the Remco RM12-80 and it's definitely and AGM.

I have had it for two years but haven't used it a lot so I can't comment too much on its performance, but I'm certainly happy that it performs as specified.

It sure has gone up in price, 2 years ago I paid $230, now it's $320 due to the price of lead going up so much.

Richard,

I'm not convinced that an AGM cannot be placed in the engine bay.

I used to run an Orbital in the auxiliary tray in the engine bay, until I irreversibly damaged it by draining it too low, too often. (maybe 3 times). It appeared to handle the heat OK and did not distort like I have heard some batteries apparently doing.

I currently have a Supercharge wet cell battery in this location, but this is also a "sealed" battery. There is no method of topping the electrolyte up, so if it gets too hot and the contents evaporate as you say, then it also will bne cactus.

I am of the opinion that providing the battery is kept away from high heat sources, such as a turbo, they should survive OK.

When the Supercharge requires replacement, the Remco will certainly be put in its place.

An Orbital AGM battery is fundamenatlly different to a standard AGM battery.

Cyclindrical-cell AGMs have the plates in direct contacte with the case allowing any heat from from overcharge to be dissipated out of the battery. Wetcell and Gels similarly have the electrolyte in direct conatct with the case allow overcharge heat to be conducted out.

Rectangular-cell AGMs have an air-space between plate/electrolyte and case making it much harder to get rid of overcharge heat.

We have a AGM in the engine bay and one mounted under the body in the rear.

The one in the engine bay does not hold charge aswell as the other one, we have tried two of them with the same result.

It's not to do with heat effecting the structure but heat effecting the inside and seperating the chemicals and not regenerating correctly.

You have to remember most AGM's are not designed for vehicle engine bay heat....most are in a temp stable enviroment.

Have a look at the specs and see if you can get a temp versus output graph.

Alot of these types of batterys have a maxium charge and discharge temp of about 50 Deg.C, in a engine bay you get anything from 70 to 100 Deg.C.

>It shows no sign of problems.

How do you know?

That's what I call a light bulb question - why isn't it working today, it was working yesterday - answer, because it wasn't blown yesterday and it is blown today. The next question is invariably "why did it blow?"

In the case of my battery, the sides are not bulging, there are no seam leaks, the car starts every time, I can turn on every electrical accessory and the headlights and the starter runs at the normal speed and the lights don't dim.

Short of taking it in to a battery place for a load test, all of the above tells me it shows no sign of problems. Doesn't mean it won't chit itself tomorrow, but if it does, I'm happy with the $80 it cost me and the use I've already had.

As it happens I'm currently involved in some testing of AGM batteries to AS4029 and the designing of electronic systems to comply with NATA requirements for same and as far as I am aware the only way one can assess the health of an AGM battery is by performing a full discharge test (ideally a number of them) in a temperature controlled (25C) environment which is why I believe motherhood statements of the ilk "It shows no sign of problems" are meaningless. Actually AS4029 also calls for a 90 "charge retention test".

$80! You were over charged (maybe your battery wasn't? :) the last ex. UPS AGM I bought (95Ah) I paid $50 - actually I bought two of them, one is still going strong (NOT under the bonnet) but the other died after about 3 months of very light use - luck of the draw.

Mike Harding

Great, I'll accept my motherhood battery for now, thanks, since it is doing all my car battery needs to do. If you say it's stuffed because you know better and it makes you feel better, go for it.

In the meantime, I'm happy to pay $80 for my battery which is still going under the bonnet - it seems you were ripped off not me, since you paid $100 for yours. (in case you can't follow my motherhood logic here, it's like this - buy 2, one no good, means you only effectively bought one)

And I'd be a mug to subject my battery to repeated full discharge tests, to prove it's OK, especially since the very act of doing repeated tests will stuff it for sure. That way you'd be right and I'd have to buy a new battery.

But thanks for proving my perfectly performing motherhood battery is really not doing what I think it is. I'll go out tomorrow and buy a new one, if I can start the car.

Gerhardp1,
I would recommend a 'deep discharge test' to ANYONE who believes he could have a problem with a "storage" battery or is worried that the "storage" battery may die on their holiday.

The way they (the test) works does NOT damage the battery !!!
I get both my AGM's and also my Cranker (Delkor Deep Cycle battery) tested EVERY year before going away to make sure it is in a realistic condition and should not give me problems *IF* I look after them when I'm away.
( fortunately my Solar system does that for me lol )

Mainey . . .

Settle down Gerhardp1:

you're arguing with Australian Standard 4029 not with me.

>If you say it's stuffed because you know better and it makes you
>feel better, go for it.

I have no idea of the condition of your battery - nor do you.

If you are going to make definitive technical assertions (as opposed to opinions) on the internet you had better be prepared to support them with technical fact and not an emotional outburst.

Mike Harding

Mike, I'm well settled, thank you for caring.

For what it's worth, I'm also totally ambivalent about AS2049 and I could care less what NATA requires.

I'm also well satisfied with my battery, it's performing well under the bonnet, and I don't care if you say it's stuffed, since it starts my car every day I know it's not.

I'm not sure where I made a definitive technical assertion, it seems you are the one paranoid about that.

Since you are the self-nominated standard keeper of the internet, you should yourself keep your emotion out of it - just because you say an AGM won't work under the bonnet, doesn't make it true - in fact it's false, since I have had mine there for 21months or so. That is a fact, not an emotion, and your opinion won't change it.

In my many years of owning various cars over the last 40 years, my battery problem diagnosis has been 100% reliable - every time one has been no good, I've picked it - the car will no longer start, has low voltage in one of the cells, the post has fallen off, the acid level is below the plates, or whatever, and never a technical fact has been able to restore the dud.

So, I'll repeat my previous comment, my battery shows no signs of problems, but it could chit itself tomorrow. If it does, my 100% record of diagnosing a stuffed battery will remain intact, and I'll get a new one, like every other time. And I'll get another AGM, and put it under the bonnet.

If your battery will start your car, it only proves it can supply 2% of its original capacity.

Mike,

""it only proves it can supply 2% of its original capacity""

not ruly truly tru is it lol

Mainey . . .