AGM <span class="highlight">Battery</span> Questions

You should have no problem in mixing battery types Bushie.

Surepower claim on their website that the Surepower Isolator "isolates each battery circuit and allows each battery to discharge and charge according to its own needs".

This is the function of all "smart" isolators and the Surepower should be no different in that regards.

As far as the brand of AGM battery, the only comment I can make is that it probably gets down to the price you can buy one for, rather than the actual brand name.

Just compare the stats on the different ones you mention and check the physical "footprint" size, (length, width, height) for the capacity size you are considering, to ensure it will fit in your cradle.
AGM batteries (for a given A/h capacity) are generally physically bigger than a "wet cell" equivalent.

Challenge Batteries in Osborne Park are worth talking to, I have found them to probably be the most customer orientated business I've dealt with and I'm yet to see anyone beat there prices. Their back up service is second to none. Its a family run business, Graham and Chris (father & son).
I have never met them, do not know them, not related to them just a more than satisfied customer.
Joe.

Hi Old Bushie

First of all ARB use a solenoid they have not got into advanced battery isolation yet.

You will have one of these fitted.



It is a voltage sensing solenoid. Just like a redarc. The contacts are rated at 85amps. We have done a fair bit of testing on isolators and give these only a 4 star rating not 5 star like others, mainly because of the voltage drop and the fact that it is not microprocessor controlled. (I have started rating products on my site.)

Your AGM will charge under the solenoid system but as it is being charged via the main battery it will take longer and not get the full 14+ volts required for 100% charging. I would use a 240V mains charger after every trip to keep it from building up sulfation.

100 a/h AGM will fit in to space as I have done this a few times already. You will need a longer J bolt and fit a spacer under the bracket at the front as the 100 a/h is 12mm higher than a standard N70.

If you look at my picture below you will see the 100 a/h sits a bit higher than normal.



Regards

Derek.

all simple voltage sensing isolators are pretty much the same and DO NOT take the battery type into consideration .. Most alternators deliver past 14V (Landcruiser 100 V8 does 13.6 and is better ) and will cook AGM's when they are full ...

www.yandina.com/c150Info.htm

above is the only "simple" Isolator combiner which takes that into account ..
the pin HiVolt is meant to be connected to the AGM plus and disconnects when full ...

there are other solutions but this is the easiest .. I have two of these in my boat
there is a smaller version which is probably sufficient for a jap 4by ...

have fun
gmd

Gday again

Thanks to you all for the informative replies. Your experience is appreciated along with all the info I have since found via the forum search (head spins!!!!).

I have used Challenge Batteries in the past and endorse your comments.

Mainey, could you provide contact details for the southern suburbs supplier you mentioned?

Derek, I do have the Shurepower Isolator you pictured. Re your advice quote:
"Your AGM will charge under the solenoid system but as it is being charged via the main battery it will take longer and not get the full 14+ volts required for 100% charging."

Am I correct in assuming this statement is also true of my current conventional battery and I would still gain the "relative" decrease in charging time that an AGM battery provides or will I only get a decrease in charging time by upgrading my Isolator?

Re brands available, after 35 years of remote outback travel, I have learned the hard way cheapest ain't always best. I am very happy to pay for quality and reliability. FullRiver seems to get mentioned a lot without adverse comment. I am interested in other brands, if from users experience, they are considered superior. eg Absorbed Power that I believe are used in some better quality boats. Does anyone know what brand Bushtracker caravans use?

A comment in post 25021 by Collyn R seems very relevant to my questions and maybe useful to others who haven't seen it quote:

Since then however, Redarc and other similar voltage sensing relays have gained wide acceptance. As long as one of these delays paralleling until the starter battery reaches about 13.6 or so volts, there seem no major problems in parallel charging and thousands of people now do so.

There is next to no risk of charging an AGM at too high a rate - they will withstand substantial input currents."

Again, thanks for the replies.
Regards

Thanks Mainey

Apologies for the delay in replying. I too have not been very far north of Geraldton fishing for the last 10 days.

I will follow up your link.

Many thanks to all of you for the informative replies.

Regards