AGM Batteries
Submitted: Wednesday, May 03, 2006 at 17:25
ThreadID:
33504
Views:
2135
Replies:
6
FollowUps:
9
This Thread has been Archived
Des Lexic
I've been doing some homework on a new battery and the AGM seems to get lots of positive
feedback. One dealer said that you should not run them in parallel with the cranking battery as the variable volts when charging them will stuff them up.
How do you guys charge your AGM when it's in the 2nd battery installation.
Reply By: Mad Dog (Australia) - Wednesday, May 03, 2006 at 17:33
Wednesday, May 03, 2006 at 17:33
Ignore him and wire it up the same as any other dual battery, It'll work just fine.
AnswerID:
170481
Reply By: Member - Peter R (QLD) - Wednesday, May 03, 2006 at 17:35
Wednesday, May 03, 2006 at 17:35
With a redarc unit.
check it out
Pedro
AnswerID:
170482
Reply By: Alloy c/t - Wednesday, May 03, 2006 at 18:01
Wednesday, May 03, 2006 at 18:01
Sed Exlic ,,as the mongrel god said above ignore the fallacy ,,AGMs by their very nature accept a wide variation in charging voltages,, any damn thing from a true 12v thru to 15v and from .75 milliamps upto how big is you alternator ???? tried an experiment where I ran a 1amp 12v fluro for 52hrs from an 80amp hr Fullriver AGM HGL , 40min connected to an 80amp Cristies gen set and batt was reading 14.25v and dropped back to 13.4v 24hrs later ,batt stays at that v for weeks/months when not used. That same batt is now 6+ years old and is used as the starter in the boat.
AnswerID:
170489
Reply By: Derek from Affordable Batteries & Radiators - Wednesday, May 03, 2006 at 18:21
Wednesday, May 03, 2006 at 18:21
Use an isolator and you will have no problems.
Redarc or ABR type is fine.
AnswerID:
170495
Reply By: Des Lexic - Wednesday, May 03, 2006 at 18:32
Wednesday, May 03, 2006 at 18:32
Thanks everyone, I have a 200 amp Redarc Isolator so looks like I have that covered.
Next step is to buy one.
AnswerID:
170497
Follow Up By: Mainey (WA) - Saturday, May 06, 2006 at 04:25
Saturday, May 06, 2006 at 04:25
First before you spend the cash, email Redarc and explain to them what it is you want to do, ask them the direct question is a Redarc solenoid actually "recomended" by them to be used with two different types of batteries, their reply will change your decision.
yes you can use it with two different batteries and you can also drive in the right lane of the freeway, but it's not recomended either!!!
FollowupID:
426506
Follow Up By: Mad Dog (Australia) - Saturday, May 06, 2006 at 11:58
Saturday, May 06, 2006 at 11:58
Who cares what the maunfacturer says the fact is it works just fine. If the manufacturers of products knew everything they'd never have to ask the consumer for
feedback would they. I work for a manufacturer and I'm damn sure the company doesn't know everything about our product. Theory is one thing, real life experience is the real
test.
FollowupID:
426569
Follow Up By: Mainey (WA) - Saturday, May 06, 2006 at 20:27
Saturday, May 06, 2006 at 20:27
Ray,
The facts are its not "recommended" by Redarc for a valid reason, hence I have posted "ask them for their reason"
To my knowledge, in no present advertising for the Redarc Smart Solenoid is there any reference at all to them being used and/or recommended with any other than two identical Cranking batteries, prior to my contact with the CEO of Redarc they did imply two different types of batteries could be used, that has since been negated.
Various Electronic Isolator manufacturers do recommend their Battery Isolator can be used with any combination of Cranking battery and AGM or Deep Cycle batteries.
FollowupID:
426651
Follow Up By: Mad Dog (Australia) - Saturday, May 06, 2006 at 20:38
Saturday, May 06, 2006 at 20:38
That's because Redarc's technical dept aren't up to play with the latest theory about dual batteries, not their fault because the myth that only identical batteries should be paralled is all over the web, even some battery manufactures aren't up with the play yet.
FollowupID:
426652
Reply By: Member - Norm C (QLD) - Wednesday, May 03, 2006 at 19:08
Wednesday, May 03, 2006 at 19:08
Yep, that's the go Des. I have a wet cell cranker, a wet cell DC and two AGM DCs. When driving, they are all in parrallel. When not driving, cranker is obviously isolated. Any other isolation depends on how I have things plugged in.
Had the set up for a year so far and all is fine. When the wet cell DC dies, I'll replace it with another AGM. I used a wet cell as it is in the engine bay and I was worried about the heat.
I reckon the AGMs are worth the premium you pay for them, so IMO, you have made the right choice.
AnswerID:
170508
Follow Up By: Member - Tony W (VIC) - Saturday, May 06, 2006 at 05:54
Saturday, May 06, 2006 at 05:54
norm ,
Excuse my ingnorance but when you say wet cell, do you mean normal acid type dc batts ? if so i always thought you couldn,t parrell different types of batteries.
because my conundrum is i have to 2 agm (extreme orbitol 55ah) one as my crank and one as my aux and also 65ah dc acid battery sitting in the shed doing squat , almost brand new.
it would be nice if i could put in my ct to run parrell with my aux, via anderson plug to charge up while driving along your thoughts most appreciated
thanks tony
FollowupID:
426507
Follow Up By: Member - Mike DID - Saturday, May 06, 2006 at 08:06
Saturday, May 06, 2006 at 08:06
"i always thought you couldn,t parrell different types of batteries."
- yet another "
well-known" battery myth.
Lead-Acid batteries (wet, agm, starting, deepcycle) can be charged with a constant voltage. It doesn't matter how many other batteries are connected to that same voltage. But keep in mind that some battery types need different voltages (e.g. calcium-calcium)
Mike
FollowupID:
426518
Follow Up By: Member - Norm C (QLD) - Saturday, May 06, 2006 at 11:44
Saturday, May 06, 2006 at 11:44
Tony, Correct. By Wet cell, I mean normal vented (not sealed) lead acid Deep cycle. As Mike has said, the 'theory' that you should not connect different battery types in parrallel has been dubunked for some time. Many people on this
forum have successfully mixed batteries. AGMs and normal vented batteries are no problem. The only potential problem I am aware of is that since an AGM can take large charging currents, it may 'rob' the charging current from the normal (vented) battery so that the normal battery does not fully charge. This is only likely to happen if you do lots of short trips and no extended running. I have never had the problem, and as far as I am concerned, it remains an unconfirmed theory (although the theory is sound).
FollowupID:
426564
Follow Up By: Mad Dog (Australia) - Saturday, May 06, 2006 at 12:07
Saturday, May 06, 2006 at 12:07
I've heard that theory also Norm but if using a good isolator that doesn't bring the second battery in until the main is charged that potential problem is overcome.
FollowupID:
426574
Follow Up By: Member - Mike DID - Saturday, May 06, 2006 at 17:32
Saturday, May 06, 2006 at 17:32
"since an AGM can take large charging currents, it may 'rob' the charging current from the normal (vented) battery so that the normal battery does not fully charge"
- if this happens then you just don't have enough charging capacity - to fix that you need to either increase your Alternator current capacity or reduce the amount of current you are drawing. Fiddling with batteries is just re-arranging the deckchairs on the Titanic.
Mike
FollowupID:
426624