Auxiliary (Dual) Battery Setup Question

[Parentnoia]

TL;DR
Seems like all you folks are over thinking this. Having lots of auxiliary lights and such is the equivalent of a huge stereo setup.
You need to worry about only two things. Alternator output while running, and the batteries' amp hours while it's off.
For alternators, look into DC Power and Mechman. They make high quality aftermarket alternators with decent idle output.
For batteries, look into XS Power. Great quality.
Both options are pricey, i will warn you of that. But the prices are worth. One XS Power battery as your main will do you just fine until you can get another.
As for hooking them up, just run one run of (preferably) 1/0 from positive to positive and one run of (preferably) 1/0 from negative to negative (or negative on the auxiliary battery to ground, the choice is yours). This is called parallel. Yes connecting them that way will drain them both at the same time, but doing it that way essentially doubles their amp hours. Therefore two batteries with 500 amp hours will produce essentially 1000 amp hours.
Imagine it this way, if you have a set of lights that draw 10 amps, no matter which battery you have them connected to, as long as the two (or more) batteries are connected in parallel, they will each only see 5 amps (or less, just divide the load by how many batteries you've got).
No need for fancy set ups and such.
Now, if you're truly worried about draining your batteries through parasitic draw, just set up a nice sized solenoid connected to a switch. It'll separate the auxiliary batteries from the main until you need them. I'll explain how to wire that if anyone's interested.

 

[df2x4]

This guy speaks the truth regarding performance alternators, I'm currently in the process of setting some money aside for a 300A DC Power INC alt. $600 is a lot for an alternator but they're pretty unbeatable for amperage at idle. Regarding XS power though, I'd urge everyone to look into Odyssey batteries instead. I've never liked the idea of using what was engineered as a dedicated car audio battery as a primary starter. XS has awful terminals, every single spec is worse than the Odysseys, they have a worse warranty than the Odysseys, and to top it all off they're more expensive than the Odysseys.

 

[DeathByNissan55]

TL;DR

You obviously read it in order to answer so shut it lol

Seems like all you folks are over thinking this. Having lots of auxiliary lights and such is the equivalent of a huge stereo setup.
You need to worry about only two things. Alternator output while running, and the batteries' amp hours while it's off.

Basically what I said sir, I wrote all that stuff so I wouldn't have to waste post space on answering those questions later.

As for hooking them up, just run one run of (preferably) 1/0 from positive to positive and one run of (preferably) 1/0 from negative to negative (or negative on the auxiliary battery to ground, the choice is yours). This is called parallel. Yes connecting them that way will drain them both at the same time, but doing it that way essentially doubles their amp hours. Therefore two batteries with 500 amp hours will produce essentially 1000 amp hours.

I think there will be many that disagree with you on here if you're saying stock cables for alt to batt, bat to block, and block to frame or body, are fine - as most of those corrode and are undersized from factory to reduce costs. So technically you could leave them, but I'd rather be safe than sorry. I also stated I'd be setting myself up for the future, and chevy pickup grounds are the number 1 electrical failure.

Now, if you're truly worried about draining your batteries through parasitic draw, just set up a nice sized solenoid connected to a switch. It'll separate the auxiliary batteries from the main until you need them. I'll explain how to wire that if anyone's interested.

I imagine it'd work much like a relay powered off a lower current control circuit like a 12V toggle switch mounted in cab or something, with the relay sized for whatever current the alternator puts out I believe. The relay would act as a solenoid disconnect that intercepts the aux batt pos lead going to the main batt pos, along with whatever other equipment you have going to the aux batt pos terminal, right?
Please post your explanation Parentnoia, when you get a chance, much appreciated Sir.

 

[Parentnoia]

I think there will be many that disagree with you on here if you're saying stock cables for alt to batt, bat to block, and block to frame or body, are fine - as most of those corrode and are undersized from factory to reduce costs. So technically you could leave them, but I'd rather be safe than sorry. I also stated I'd be setting myself up for the future, and chevy pickup grounds are the number 1 electrical failure.

The question was not about replacing stock wiring, the question regarded adding a battery setup. Yes, replacing stock positive to alt, negative to ground, and block to ground is good.

I imagine it'd work much like a relay powered off a lower current control circuit like a 12V toggle switch mounted in cab or something, with the relay sized for whatever current the alternator puts out I believe. The relay would act as a solenoid disconnect that intercepts the aux batt pos lead going to the main batt pos, along with whatever other equipment you have going to the aux batt pos terminal, right?
Please post your explanation Parentnoia, when you get a chance, much appreciated Sir.

You've actually got it pretty well explained yourself. But it'd be a better idea to set the turn on circuit of the isolator to activate by a wire that's hot at ignition, that way you'll never forget to flip that switch and connect the two.

This guy speaks the truth regarding performance alternators, I'm currently in the process of setting some money aside for a 300A DC Power INC alt. $600 is a lot for an alternator but they're pretty unbeatable for amperage at idle. Regarding XS power though, I'd urge everyone to look into Odyssey batteries instead. I've never liked the idea of using what was engineered as a dedicated car audio battery as a primary starter. XS has awful terminals, every single spec is worse than the Odysseys, they have a worse warranty than the Odysseys, and to top it all off they're more expensive than the Odysseys.

XS Power sells starter batteries and dedicated car audio (auxiliary) batteries. And they can be had for under $300.
As for Odyssey Batteries, they look identical to XS, save for a few of the slimmer models. And they look to cost about the same as an XS. Also, it looks like they are not AGM. I'd rather an AGM battery, especially for off-road applications, since there is a lower likelihood for losing some of the battery's contents in large bumps and potential rollovers (in rock crawling applications).

EDIT: Further research and cross-referencing has shown that Odyssey has two different definitions for their own batteries. One page refers to them as "dry cell" which is defined as "using a paste electrolyte, with only enough moisture to allow current to flow." But another page on their same site states "No, the ODYSSEY battery is NOT a gel cell. It is an absorbed electrolyte type battery, meaning that there is no free acid inside the battery; all of the acid is kept absorbed in the glass mat separators. These separators serve to keep the positive and negative plates apart. The key difference between the gel cell and the absorbed glass mat (AGM) cell lies in the fact that in the AGM cell all of the electrolyte is in the separator, whereas in the gel cell the acid is within the cells in a gel form. In fact, if the ODYSSEY battery were to split open, there would be no acid spillage." Absorbed Glass Mat (AGM) is defined as "differing from flooded lead acid batteries in that the electrolyte is held in the glass mats, as opposed to freely flooding the plates. Very thin glass fibers are woven into a mat to increase surface area enough to hold sufficient electrolyte on the cells for their lifetime. The fibers that compose the fine glass mat do not absorb nor are they affected by the acidic electrolyte."

So their own literature is confusing. XS Power is straight forward with what they offer.

 

[RyanMerrick]

I can't speak for XS, but I can say that Odyssey batteries (and the DieHard Platinum line which are manufactured by Odyssey) are the best batteries I've ever owned.

I won't buy any other battery for any of my vehicles from now on.

 

[RyanMerrick]

The question was not about replacing stock wiring, the question regarded adding a battery setup. Yes, replacing stock positive to alt, negative to ground, and block to ground is good.


You've actually got it pretty well explained yourself. But it'd be a better idea to set the turn on circuit of the isolator to activate by a wire that's hot at ignition, that way you'll never forget to flip that switch and connect the two.


XS Power sells starter batteries and dedicated car audio (auxiliary) batteries. And they can be had for under $300.
As for Odyssey Batteries, they look identical to XS, save for a few of the slimmer models. And they look to cost about the same as an XS. Also, it looks like they are not AGM. I'd rather an AGM battery, especially for off-road applications, since there is a lower likelihood for losing some of the battery's contents in large bumps and potential rollovers (in rock crawling applications).

EDIT: Further research and cross-referencing has shown that Odyssey has two different definitions for their own batteries. One page refers to them as "dry cell" which is defined as "using a paste electrolyte, with only enough moisture to allow current to flow." But another page on their same site states "No, the ODYSSEY battery is NOT a gel cell. It is an absorbed electrolyte type battery, meaning that there is no free acid inside the battery; all of the acid is kept absorbed in the glass mat separators. These separators serve to keep the positive and negative plates apart. The key difference between the gel cell and the absorbed glass mat (AGM) cell lies in the fact that in the AGM cell all of the electrolyte is in the separator, whereas in the gel cell the acid is within the cells in a gel form. In fact, if the ODYSSEY battery were to split open, there would be no acid spillage." Absorbed Glass Mat (AGM) is defined as "differing from flooded lead acid batteries in that the electrolyte is held in the glass mats, as opposed to freely flooding the plates. Very thin glass fibers are woven into a mat to increase surface area enough to hold sufficient electrolyte on the cells for their lifetime. The fibers that compose the fine glass mat do not absorb nor are they affected by the acidic electrolyte."

So their own literature is confusing. XS Power is straight forward with what they offer.

http://www.odysseybattery.com/design_advantages.aspx

Pretty dang straightforward, not sure why you're confused.

 

[Parentnoia]

http://www.odysseybattery.com/design_advantages.aspx

Pretty dang straightforward, not sure why you're confused.

That page is the one I referred to as claiming their batteries are "drycell". Now click yourself over to the FAQs (here) and read it. On their same site, they claim their batteries are AGM batteries. Can they not make up their mind, or do they not know what type of battery they make?

Let's look at side by side specs of a group 34 battery.

• Odyssey
  • Cold Crank Amps (starting): 850A
  • Amp hours @ 20A/hr: 68min
  • Amp hours @ 10A/hr: 62min
  • Reserve Capacity (25A @ 80 degrees F): 135min
• XS Power
  • Cold Crank: 1000A
  • Amp hours @ 10A/hr: 65min
  • Reserve: 135min

Stats seem a bit even.

Either way, this thread is getting derailed. Agree to disagree.
Moral of the story, adding a battery is easy. It only gets complicated in highly specialized applications. I dont think your everyday application is specialized enough to require specialty equipment.

 

[df2x4]

That page is the one I referred to as claiming their batteries are "drycell". Now click yourself over to the FAQs (here) and read it. On their same site, they claim their batteries are AGM batteries. Can they not make up their mind, or do they not know what type of battery they make?

Let's look at side by side specs of a group 34 battery.

• Odyssey
  • Cold Crank Amps (starting): 850A
  • Amp hours @ 20A/hr: 68min
  • Amp hours @ 10A/hr: 62min
  • Reserve Capacity (25A @ 80 degrees F): 135min
• XS Power
  • Cold Crank: 1000A
  • Amp hours @ 10A/hr: 65min
  • Reserve: 135min

Stats seem a bit even.

Either way, this thread is getting derailed. Agree to disagree.
Moral of the story, adding a battery is easy. It only gets complicated in highly specialized applications. I dont think your everyday application is specialized enough to require specialty equipment.

I'm sorry but I'm not sure where you're getting any of that information.

XS 34/78:
http://4xspower.com/bci_group/78/

Odyssey 34/78:
http://shop.odysseybattery.com/p/34-78-pc1500dt-a?pp=12&sort_selection=price_high_low

Like I said... XS has worse terminal options, worse specs (although I admit they are close, but XS doesn't even list cold cracking amps like you stated, just standard), and are way more expensive. If none of that matters to you then hey, whatever. Also the Odysseys are most certainly AGM. I have confirmed this with a local dealer.

 

[Parentnoia]

I'm sorry but I'm not sure where you're getting any of that information.

XS 34/78:
http://4xspower.com/bci_group/78/

Odyssey 34/78:
http://shop.odysseybattery.com/p/34-78-pc1500dt-a?pp=12&sort_selection=price_high_low

Like I said... XS has worse terminal options, worse specs (although I admit they are close, but XS doesn't even list cold cracking amps like you stated, just standard), and are way more expensive. If none of that matters to you then hey, whatever. Also the Odysseys are most certainly AGM. I have confirmed this with a local dealer.

CA = Cold crank
They sell side terminal adapters.
$259.99 vs $311.82

I'm sorry if my preference is with the company where I can talk to the guy making them, rather than joe blow selling them.

 

[df2x4]

CA = Cold crank

No, not really.

I'm sorry if my preference is with the company where I can talk to the guy making them, rather than joe blow selling them.

The Odysseys are made in my home state by Enersys, the factory is less than three hours away from my house. As far as I can tell XS has no claim as to even country of origin on their products. Also, I wouldn't call an authorized Odyssey dealer who's been in business since 1980 "joe blow selling them," but like you said, agree to disagree.

EDIT - Upon further research it appears that XS manufactures their stuff in TN somewhere so there's that at least. I still stand by my statements. The XS may be marginally cheaper than the Odysseys depending on where you buy them, but I'd say the extra year of warranty (minimum, depending on which XS product line you purchase from) more than makes up for that. I'm also not sure about the details on the XS warranty policy, the Odyssey warranty is four years free replacement, no questions asked. Add my other points of interest (like the terminals) and it's a no-brainer as far as I'm concerned.

But hey, in the long run it's your truck and your money. Buy what makes you happy. I will derail this thread no further.

You must be registered for see images