Teach me about dual battery systems

[asteffes]

Which dual battery systems are you folks using? What have your experiences been? Are these systems reliable (I mean dead-on, Toyota-factory-quality reliable?)

Grazie.

 

[Pskhaat]

I use a complete KISS system and nothing fancy. What I have is my auxilliary battery is Group 24 Marine Deep Cycle. It is grounded with 0/1 guage at the frame and body; it has a 0/1 cable that runs between it's positive terminal and the starting battery's positive terminal running through a high-amp solenoid switch.

The solenoid switch is engaged from a 12v asserted signal from the ``alternator good'' teed off from the `ALT' fuse in the FJZ80's engine compartment. This means connect (and charge) the two batteries if the alterator produces power, else the two batteries stay disconnected.

All accessories are run off the auxilliary deep cycle battery. When truck is off, I can run stereo, lights, etc etc without draining the starting battery. I additionally run a secondary momentary dashboard switch that, like the alternator good signal, closes the solenoid switch and connects the two batteries: this allows me to a) charge my starter battery from the aux. and/or b) start from the aux.

This is the super simple way of doing it. Many people will use isolators (which introduce voltage drops), and add other manual overrides, switches, automation etc. The batteries ARE of two different kinds, but I've had my dual setup for ~7 years and have yet to have an issue, and in fact have benefited many times when my starter battery dies (seems to be every 2 years in AZ heat and WI cold, no matter which of my vehicles or brand of battery I buy).

 

[DaktariEd]

Good info here: Hellroaring Technologies
This is the system I am having installed...not in use yet.
Hope to have it soon...


Ed

 

[Pskhaat]

Is this your nephew doing this? (Is that right?) Where are you putting the second battery in the 40? We talked at the Rally about the whiz in your family who is so good at doing this stuff.

If so, where is he and does he want some side work? ;-)

 

[gjackson]

I've had the Hellroaring system in my 110 for 2 years. Runs a optima yellow for the house and a red for the truck. I got the Hellroaring selector switch so I can select which battery charge is going to.

Worked very well, with no problems. So reliable I never even thought about it on 30,000 African miles last year.

cheers

 

[DaktariEd]

Is this your nephew doing this? (Is that right?) Where are you putting the second battery in the 40? We talked at the Rally about the whiz in your family who is so good at doing this stuff.

If so, where is he and does he want some side work? ;-)

Yup...that's Jake (Tacominator on this forum) doing the work for me. I just talked to him tonight. Looks like he got it installed, the clutch repaired, swapped out a gauge for me, and even cleaned up the rat's nest of wiring in the engine compartment. :victory:

The second battery (Optima Yellow) plus the isolator and switch are in the passenger side back of the 40 in my drawer unit (I made a dedicated battery compartment in it).

Now, air conditioning repair and I'm ready to roll again!

Ed :elkgrin:

 

[flyingwil]

Now, air conditioning repair and I'm ready to roll again!

Ed :elkgrin:

A/C What for? You should be able to push that off for a couple of months now, Ed! If Jake doen't know how to do that I know a great place up here on the East side of PHX that does great work and are very reasonably priced.

Wil

 

[RAM5500 CAMPERTHING]

Here is my setup:

http://www.yankeetoys.org/mangler/dualbats.htm

I just got back from 4 days in Baja running 2 Norcold 45qt Fridges, one on fridge and one on freeze and it worked great!

We ran our lantern rechargers and such from the inverter with no problem.

I wanted to keep my dual bat setup as simple as possible to limit parts that can fail!

 

[asteffes]

I'm really liking the Hellroaring kit. The simple 1-2-both-off switch is a clean idea, but I don't want to have to ever cut power to the truck if possible. Radios lose settings, things reboot, lights go out, etc. I also would like automatic charging of both batteries.

I can envision using the Hellroaring kit with a pair of Optimas. However, having learned from previously prepping a track car, I'm going to plan twice, mod once with the truck, so I'm not rushing. This will definitely go on the to-do list. First item on that list is working a budget for truck outfitting. :Wow1:

 

[calamaridog]

I'm planning on using this:

http://www.perfectswitch.com/whypgate.htm

I will use the SR-250 amp isolator. The second battery will power the winch, lights, and accessory fuse block.

This product is small, produces little heat, and requires no switching on and off. This product is fairly new to the marketplace but I know several people using the product with no problems.

BTW, I'm using an Odyssey 1200MJT as the starting battery and will use either a 1200 or 1700 for the accessories.

 

[DaktariEd]

A/C What for? You should be able to push that off for a couple of months now, Ed! If Jake doen't know how to do that I know a great place up here on the East side of PHX that does great work and are very reasonably priced.

Wil

Hey, Wil,
Just figured since he has the 40 now might as well get it done all in one trip.

 

[Scenic WonderRunner]

Although I would like to have a dual battery set up.....I really don't think I have room for it in my 1988 Toyota 4Runner.

However........I did run across this battery. Looks like it's made for motorcycles. The CCA is high like an auto battery....and the dimensions look like it could work somehow.

So how about a main battery : Odyssey 1200MJT

Aux Battery: Odyssey PC680

Any thoughts?


PC 680 Specs:

680 cranking amps for 5 seconds
595 cranking amps for 10 seconds
525 cranking amps for 20 seconds
17 amp hours
Short circuit current over 1800A
25 minute reserve capacity with 25amp load
Female brass terminal w/M6 SS bolt
Length 7 1/16"
Width 2 15/16"
Height 6 9/16"
Weighs less than 14.5 lbs
Odyssey design:

2 year full warranty
Rugged Drycell sealed design
Military grade
Vibration resistant
60% more starting power
Deep discharge reserve power
2 year storage life
8-12 year design life
Can be mounted flat or upright

 

[asteffes]

Those are very good quality batteries, often used in racecars. They're known to survive harsh vibration, but I do not believe they handle deep discharge well. You'll want to be careful that you don't fully discharge as it won't handle that as well as, say, an Optima Yellow Top. I probably wouldn't use it to run a winch.

 

[Scenic WonderRunner]

The ODYSSEY® Drycell battery combines in one box the characteristics of two separate batteries. It can deep cycle as well as provide enormous cranking power.

These dry cell batteries are capable of providing engine cranking pulses in excess of 2150A for 5 seconds as well as 400 charge/discharge cycles to 100% depth of discharge (DOD). A typical starting, lighting and ignition (SLI) battery can do one or the other, but not both. Conventional batteries are either a sprinter or a long distance runner; An ODYSSEY® battery will do both — provide short duration high amperage pulse or low rate long duration drains.

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[asteffes]

Yeah, I've read that too, but in the experience of a few folks I know they don't quite live up to those numbers. Still, it's not a bad idea to give one a try. No battery should be abused.