Hodge's Dual Battery System

[Hodge]

OK time for me to expand this cars travelling luxuries. I need to organize and get a dual battery system fitted. So I need to know if this is the right path to go.
I don't need anything extravagant. I'll only be running a fridge and a few lights at the back for now anyway.
This is what I've come up with.
Already have a battery tray under the hood so this is already done.

- Redarc BCDC 25A unit with MPPT for future solar provisions if I ever go down that path.
http://www.ebay.com.au/itm/REDARC-BC...fe02e03&_uhb=1

- At the back I'd like one of these units. I'll be running an ARB fridge so, this has an engle socket ready to go, as well as a few other bits. And fits nicely in the corner at the back.
http://www.ebay.com.au/itm/BAINTECH-...170c6d4&_uhb=1

- Battery? Now this is my biggest puzzle. Recommendations are most welcome. As above, I'll running a fridge, few lights, charge a few phones etc... Nothing special. Something around 100Ah perhaps ???

Shoot me with opinions please.

[Family4x4]

Another option for the back.

http://www.ebay.com.au/itm/400581545...84.m1438.l2649

[Hodge]

Thanks mate. Definitely an option with more features, and I'm 50/50 between that one and the one I listed. Although the one I listed replaces that rear corner pocket as its designed to fit in perfectly and looks neat.

[graeme1969]

Gday,

This battery that mitch.mccabe purchased on here a couple of days ago seemed to receive favourable comments.

http://www.nissanpatrol.com.au/forum...e-single/page4

[sooty_10]

Hodge although the redarc is a decent unit just be aware that a simple dual sensing solenoid utilising the alternator will bulk charge a battery under the bonnet a lot quicker. If your running long lengths of cable a DCDC charger becomes beneficial due do voltage drop. The redarc will still work damn good and probably get that last ~10% charge more efficiently. However a simple smart solenoid setup will be a fair bit cheaper. There is quite a bit of info on the site and no doubt you've already read it, just thought I'd add it here.

[the evil twin]

What he said ^^^^

The three biggest reasons IMHO...
I am not a fan of putting those complex units where they are constantly subjected to high temps under the bonnet.
Considering the cable run is probably 2 metres or less there is not much point because, as Sooty mentions, you get bugger all voltage drop
They won't connect back to the Cranker for Jump starts like a "smart solenoid"

[Hodge]

Much thanks for the replies. Evil and Sooty, I can see your point. Till now I haven't even thought or considered a simple option like that.
I'll be doing some homework on this, over the next week. Battery is decided.
This battery seems like a winner though. Thanks Graeme. Purchased from that shop many times, always good service.
http://www.ebay.com.au/itm/130AH-AMP...d=618662801959

[Hodge]

Alright, I need to step this up a level. BCDC1225 25A unit is decided, as I scored one for peanuts. I will be running 8 gauge wire to the back, through a fusable link block, and then onto relevant loads, which will just be a fridge, rear light and some LED light strips around the doors etc...

Running the wire to the back... Need opinions, did you run it through firewall, and then under the trims between doors and seats, or did you run underneath the car and popped back up at the rear?
The other thing is, AGM batteries not so good under the bonnet? I didn't know this until someone mentioned to me today. So more confusion. :S

[mudski]

Just get a deep cycle for under the bonnet mate. you can run them almost flat and recharge them. Decent deep cycles are designed to discharge down to around 20% of its capacity, the cheaper units maybe around 40%.
A Redarc SBI12 would be more than enough for under the hood too. And still cheaper than the DC-DC.

[deanfurley]

Just get a deep cycle for under the bonnet mate. you can run them almost flat and recharge them. Decent deep cycles are designed to discharge down to around 20% of its capacity, the cheaper units maybe around 40%.
A Redarc SBI12 would be more than enough for under the hood too. And I'll still cheaper than the DC-DC.

I thought like 80% was the minimum? I thought 12.7 volts was the danger level.

Choppa seems to be the man to talk to about this stuff, from what I have read.