Dual Battery How To??

[cobbcfi]

My 99' Yukon has the empty battery tray on the driver side and I want to put my "deep cycle" boat battery over there to keep it charged and conditioned.

Will putting a deep cycle battery in the second tray hurt anything?

What do I do to set it up correctly?
Do I just get another set of wires and run positive to positive and neg to neg from the original battery?

Will the alternator also keep the second battery charged?
That's what I am really after here.

 

[_Dylan_]

Yes run it in parallel for 12v.

The alternator will keep them charged. Some people say it is bad to have two different batteries, so maybe save up and buy two new batteries?

I would also suggest installing a dual battery switch from a boat. There are many diagrams on google for this.

 

[SunlitComet]

if you are patching them together like you say both will have to be regular or deep cycle battery but not a mix of both. if you use a battery isolator you can use both and your boat battery will stay fresh until you need it. Or you could just by a deep cycle maintainer that plugs in to household electricity.

 

[domin8]

I don't think you need to run the negative cable from the second battery to the first. A simple ground should suffice. I did this. The negative is ground to the engine block and the positive runs to the jumper block on the first battery.

 

[bsamoul]

When I did mine, I bought this: http://www.sonicelectronix.com/item_16886_Stinger-SGP32.html

I also did the big 3 and got a big alternator. 14.5 v to both batteries always.

 

[sparg93]

+1 on sunlit's comments.

do NOT run them in parallel...

Definitely pick up a battery isolator. There are a ton on the market (from cheap "dumb" relays for $50, to $300+ National Lunas). The higher end ones allow momentary connecting for when you're pulling a high load (i.e. winching), monitoring and some other gizmos. This will also allow you to run accessories (lights, stereos) with the truck off and not have to worry about the starting (primary) battery dying.

I can't remember the name of the one I bought, but it was a marine isolator with remote and manual switching...i think i paid $135 for it and it was highly rated amongst the 4x4 guys with mult batteries.

 

[cobbcfi]

I put both deep cycle batteries in my truck instead of 2 different types.. One wired as it was and the second I ran the positive cable from the battery to the fuse junction that fuses power from the alternator to the original battery wires and used the extra connection point to run the second battery. Basically the second battery is not providing any power to the vehicle, it is only getting a charge. The negative is wired to the engine.

I frequently check the batteries and wires for abnormally hot wires, terminals and swelling of the battery and it all seems to be working fine.

Q - What risk am I running with a battery that is only getting charged?

My trips are almost always less than 30 minutes each way..

Thanks for any warnings or conformation that what I have is OK..

 

[SunlitComet]

you are now running them in parallel. and the second battery is also providing power to vehicle unless you have it diode isolated. Not really the ideal way to wire it really but you are essentially doubling the storage capacity o f the battery system if the batts are the same size in terms of capacity.

 

[retorq]

Link to factory dual battery isolators/diodes??