2nd Battery Replacement - Advise Needed!

Alex

I have two batteries in my 80 series just connected with a solenoid. This has worked fine for many years. On the advice of an auto electrician I keep the two batteries the same size (capacity) and have had no problems with battery life. I replaced both at the same time. Current ones been there for three years now.

I run a fridge plus lights off the second batery.

Alex,

Does the Dual Battery setup have a control unit (Isolator?)
This is the most important part of any dual battery system
Firstly, it allows the primary (starting) battery to be charged first, then swaps over to enable charging of the auxiliary battery.
Secondly, a good quality Isolator will keep the two batteries separate from each other.
In this way, if one battery becomes flat, it will not drain the other battery.

A cheap, but easy way of maintaining a watch of one or the other batteries is to use a volt meter mounted in the cab. Such a volt meter is available from Jaycar (Cat no. XC0116) and sells for just under $40. This has a cigarette plug already on it. In my setup, I have an additional ciggy socket mounted under the dash, which is connected to the auxiliary battery to power low current devices such as the laptop, camera charger, etc.
To check one or the other batteries I simply plug the voltmeter into either the original ciggy socket to monitor the primary battery, or the additional socket to monitor the auxiliary battery. Simple, but it works. I attach the voltmeter to the dash via Velcro.

The Fullriver battery you mention is a good choice for your stated needs, including the fridge. Just make sure the physical footprint (length and height) will allow the battery to fit into the existing cradle. This may or may not be a problem.
The batteries do not need to be the same type, brand, or capacity unless you are using a “dumb” isolating device.

Finally, a low voltage cut-out device will protect your battery from severe discharge.
The Waeco fridge has this built-in, but a separate Projecta brand unit can be bought from Kmart or Repco for around $30. This will isolate the fridge from the battery once the voltage has dropped to 11.6 (about 70% discharged).

Good luck with your choices.

Alex i run about the amount of gear as you with a fridge and have a Fullriver 60AH AGM sealed battery, works fine for me and have had no reason to change, i also run a Traxide Tronics dual battery controller to keep it all in check, at $110 i can't complain.

Baz.

Years ago my battery died on the way home from a solo Simpson crossing...about 1983 I think. My rule now is if the batteries are over 18 months old, I replace both of them before doing a major trip. That way I'm fairly sure that whatever other hassles I may have, batteries aren't one of them.

Alex,
if you require a Deep Cycle Storage battery then you have not done your research well enuff L0L,
you stated.... "I've been doing my research and reckon the Fullriver 12 volt 80Ah AGM Technology HGL Series battery would do the job. Any opinions"

Not just an opinion but a real fact - the "HGL" is NOT a Deep Cycle Storage battery..... :-(
check out the Fullriver web site for more technical information.

You want a Fullriver Deep Cycle battery get a "Deep Cycle" battery!!!

Yes, they are sold and labelled as the "DC" battery range, common sence really.

The battery you have chosen will fit straight in to the cradle and do the job easy , even the 90 Fullriver hgl will fit ,