Dual Battery Setup (2 Viewers)

[Cruiserdrew]

Not exactly true... If you run a single battery, I believe deep cycle batteries are better than starter batteries if you are going to run an SUV with power draining accessories (winch, fridge, lots of lights, ridiculous sound system, etc). The starter battery is not what you want to rely on in a situation where you are having to put a huge load on the battery between cycles. Winching is an ideal example. If I switch to a dual setup, the starter/deep cycle makes the most sense. Since I have power draining accessories and a single battery, deep cycle is my preference. I love these debates.

Just to correct one thing here, it is generally better to connect a winch to a starting type battery because of the high instantaneous current draws. A starting battery is better at that. No batteries can run a winch all that long. If you can combine batteries when winching, that's even better. Not necessary, but better. Warn lists the recommended capacity of the battery for each winch on their website.

A deep cycle battery is way better at a significant total discharge like a fridge running flat out all night, or a CPAP machine which was the example here. Starting batteries don't really appreciate a 50% discharge, where as a deep cycle is built to take a 50% discharge.

@weejub looks like good choices in the battery department given your size issues. Ha-size issues, sorry man.

 

[weejub]

. . .

@weejub looks like good choices in the battery department given your size issues. Ha-size issues, sorry man.

Pearl the Tundra is "female" - otherwise I am worried we would be having a "tiny hands" discussion!

I had to talk to her nicely and buy her a lot of other things before putting two batteries in a spot only made for one.

 

[weejub]

Size your fuse to your wire. . .

Size the wire to the load, then size the fuze to the wire.

I have been looking at a LOT of stuff and forgot this advice and bought 80 Amp ANL fuses. Given I am using 2 gauge wire and my alternator is ~ 85 Amps output and I think the length of the wiring will be <2 feet, I probably should bump this to 100 Amp ANLs?

 

[Cruiserdrew]

I'd do 150A with 2 ga, but anything smaller will be safe. I doubt you'll pop an 80. Even it can take 150 amps for 5 seconds-see the delay curve here:

ANL Fuse - 80 Amp - Blue Sea Systems

 

[GLTHFJ60]

As long as your fuse is at, or below, rated amperage load of the wire, then you're safe.

 

[weejub]

Thank-you @GLTHFJ60 and @Cruiserdrew

 

[weejub]

Ok here is more info on the dual battery set up.

I am drawing things out. I like this set up so that I would have only my alternator and winch and starter on the starter battery and the rest of the fuse box on the house battery.

 

[weejub]

I need to research / figure out how the starter ties in, as I see the "big" wire and then the fuse box wire on the current battery.

New batteries sitting how they will go in:

Will likely put the Winch Switch (on/off), the Relay Switch (on/off/combine) and the Relay on the firewall above the brake master etc:

 

[Cruiserdrew]

Here is a better wiring sceme that I think @concretejungle used:

 

[weejub]

Anyone use these type terminals?

Amazon.com: 2pcs Battery Terminal 2x4ga+2x8ga Positive Negative Auto Car Audio Modification: Automotive

 

[Cruiserdrew]

Those are junk audio type terminals.

Mo bettah...

Amazon.com: Pico 0810PT Military Style Top Post Battery Terminal 1 Set Positive and Negative per Package: Automotive

 

[GLTHFJ60]

+1 for what Drew linked. I used terminals very similar to that.

 

[weejub]

Glad I asked . . Thx.

 

[jamesurq]

Anyone use these type terminals?

Amazon.com: 2pcs Battery Terminal 2x4ga+2x8ga Positive Negative Auto Car Audio Modification: Automotive

I disagree with the "junk audio" comment. I just put a set of these on the 60 and they're built quite nicely. Apart from the lack of a ring terminal connection, they're nice.

 

[concretejungle]

The wiring diagram that Andrew posted above is what i used.

 

[GarnerFJ40]

I've got a similar setup, but I have my secondary fuse block (in the passenger side rear panel) wired directly to my second batery. I didn't see the need to use my Blue Sea switch to turn it on and off, just to combine the batteries. My winch is also on the starting battery, for reasons already mentioned. Fridge, rack lights, and auxillary charging plugs are the second battery. Also using the Bue Sea ACR. But my second battery is grounded seperately, and not to the first battery.

I've also used these with good results. I like the multiple connections for the winch connections and to the switch and ACR.

Amazon.com: XScorpion Silver Finish Ring Terminal Connection Style Battery Terminal: Automotive

 

[concretejungle]

The reason i like my fuse panel on the switch is so that for any reason there is a problem, i want to work on it, or just simply turn everything off for storage or any other reason, i can with the flip of the switch.

That's why mine is on the switch.

 

[Cruiserdrew]

The reason i like my fuse panel on the switch is so that for any reason there is a problem, i want to work on it, or just simply turn everything off for storage or any other reason, i can with the flip of the switch.

That's why mine is on the switch.

My logic too. Wired like the diagram, you turn the switch to off, not only does the #2 battery go off line, and your interior go dead, but you also return the truck to "normal" pre-mod operation. Turn it to "on" and the ACR is live to combine and charge the batteries and the interior fuse panel is powered. Turn it to "combine" and you have double the winching power or a self jump with no cables. Pretty slick.

 

[concretejungle]

Like cruiserdrew said above and had to explain to me, keep in mind if you are parked and do not have solar to "recharge" from, when the switch is on and your accessories are pulling power from the "house" battery, it will disconnect the starter battery so that it stays charged.

I confirmed that this past weekend on a camping trip.

 

[weejub]

New diagram with the changes Andrew showed me Also the other stuff . .

Also found out the hard way that Anderson Powerpoles only work like-for-like color with each other Anyone want to trade a grey 2 AWG or a red for the other? j/k