dual battery questions

[Bigcheck1]

i did some looking around here but havent found out exatly what i'd like to know. my question to you guys is how do i wire up 2 batteries? i want to leave the optima under the hood and add a second one in the trunk. can i wire them up through an isolator? should i then put all of my extra things, winch, system, lights on that 2nd battery? or could i just leave them where they are, wire the 2 batteries together through the isolator and then have 2 fully charged batteries at my disposal? what would i gain from having dual batteries anyway? the only reason i might do this is because i have an extra brand new optima sitting in my garage.

thanks guys.

 

[Alec]

You'd gain being able to start off the second battery if the first one is drained; you could wire them up series/parallel to get 24v to a welder or winch; more shock absorbtion in the electrical system; more constant power.

Basically you'd add the second on with an isolator and switch to the second one if your first one is drained. If you want 24v you'd need to get a series/parallel isolator that can run the batteries in either hookup mode.

Depending on the isolator, you may need to change your accessory wiring. Some isolators you wire up all accessories to the isolator so they're always powered, some you leave it on the primary battery (but then they may not be powered sometimes), some you wire them up downstream of the battery/isolator system.

 

[Alec]

One more thing:
If you're seldom worried about draining your battery but still have the spare; since it's a sealed Optima throw it in with your trail equipment as a spare part. Keep it on a trickle charger in your garage.

 

[Arnie897]

It all depends on what you're looking to do with your second battery. Right now I have a second one in the "trunk" running off of a relay I bought of eBay. I'm running my amps and a mini-fridge off my second battery so that when I'm camping I can have cold b**r and some tunes without having to worry about not starting up the next morning.

 

[Bigcheck1]

One more thing:
If you're seldom worried about draining your battery but still have the spare; since it's a sealed Optima throw it in with your trail equipment as a spare part. Keep it on a trickle charger in your garage.

thats a good point. i think the majority of the time, i'm not concerned with draining the battery so much, but the idea of having more cushion for the elect. system is appealing. withmy lights on and my system hitting, my lights still dim some. i have a cap and a 130 amp alternator currently. since this truck will be getting completley redone soon, SAS, and 37's are real close now, i will be using it only on the trail, so i have be thinking about my winch too. thats where i'd like to be able to swithc between batteries and possibly have 24 volts at my disposl. think i should just buy an isolator and a switch? not too sure how to wire everything up yet? any suggestions. i'm more of a motor and suspension guy as compared to electronics.

 

[Arnie897]

I'd get a big ol 200 amp relay for $30 bucks...it will do the same thing as a more expensive isolator.

 

[Alec]

for a 12v system the batteries need to be in parallel. for 24v they're in series. that's why you'd need a series parallel switch. These are commonly found on big rigs.

 

[cdsl227]

Jeffe has a thread with diagrams for a dual battery tray for the front. I used his tray design and an isolator. Optima Red to run the truck, Optima Yellow to run the winch, amps, aux lighting...I'd put the second batt up front, no sense knocking your head against the wall running all that wire.

It's been working out well for me. Left my lights (headlights) on once and just used a booster cable to start. I haven't gotten around to wiring via a relay for boosting myself. I also threw in a 200 amp alternator, my only problem is I need to get the smaller pulley to put out more at idle.

http://www.hellroaring.com/rv.htm

They have the best isolators I've seen...I plan on getting one of the switched ones, but for now the isolator I have is ok.

 

[Crankcase]

If the truck is a 1992 .....the second battery can be placed on the driver side with a second battery tray.....

It is how mine is set up....

 

[general x]

good ol 92 ay cranky I figure if you get some kind of snorkle you could prolly mount a batt where the stock airbox used to be (I just looked and guessed so i have no idea if it would work)

 

[Crankcase]

To mount it on the driver side, you turn the washer resivoir 90 degrees.....

 

[Bigcheck1]

To mount it on the driver side, you turn the washer resivoir 90 degrees.....

crankcase, have any pictures of how yours is set up or wired? i'd be very interested in how you wired yours up and how you fit it all under there. i would love to get them both under the hood if possible.