Dual batteries and optima weight stuff.

Does anyone know the weight of the optima batteries compared to the factory battery?

Reason I ask is because I found a potentially good place to put a second battery, but most people wouldn't want to do it if it adds too much weight. Basically, I was under the front of my X and realized that there is tons of room behind the ARB on the passenger side. I don't have a winch, but I don't think that would affect the end section. Anyway, I was thinking a tray could be built up in there to hold a second battery and it would be close to the other one. If the Optimas are lighter, then a reduction of weight in the regular spot would help to balance out the extra weight in the corner of the bumper, I think.

has anyone else thought of this or am I the only one coming up with silly ideas?

Chuck,

There are a number of people looking for alternatives for mounting dual batteries. I was forced to locate mine in the rear over the rear wheels (a good place to mount them for weight distribution) so I could make room for my air compressor. The only negative side to mounting it in the bumper is if an accident occurs. It puts the battery in harms way and creates a potential fire hazard if it should short in an accident. I wish Nissan gave us more room under the hood. Making stuff fit can be quite a trick.

But I ditched the idea because I'm always dropping my ARB into water holes (edge of streams and the like), and I don't want to submerse the battery.

Good luck if you end up trying it though!

Im not much of a 4wd expert, but isnt being worried about the extra couple of kilos a battery will add a bit unnessacry? You guys seem pretty into your off road work, (why else would you need the extra battery) so your going to be carrying lots of extra gear anyway, things like spare wheels, chains, ropes, etc, not to mention really heavy things like passangers. I really dont think you could ever feel any diffrence from adding an extra battery.
And if your worried about dunking it, then try one of the new Sealed gel types, they can be mounted anywhere, in any position, and are deemed less of a fire hazard. They can be hard to find, but because of thier upside down mouting ablity, and very steady current supply are often used by Car Audio guys. So if you cant find one at the usual spots, try a car Audio supplier.

I have been looking for a place for a second battery for some time.

I are with War I wish that they had made some more room under the hood.

I would not want the battery under the ARB I don't think that this is the best place for it. I would like it to be a little more protected from the elements (Water, Mud, Snow, etc...).

I still think that once I get a new bumper and more the spare either to the back or the top I will look at getting a box made for the rear portion of the truck. This will be where I will put the battery and possibly other stuff.

re:silly ideas

My last resort will be to mount a big hood scoop and hide the battery in there :)

I will call it my "Power Bulge"
:D

I still wonder if you couldn't use a battery box like War has in his truck, and put the 2nd Optima in the rear right behind the center console? Seems like there would be lots of bolting options, and it wouldn't effect your passengers since they could use both doors to get in. They would just have problems sliding across.

That could be an idea.
You keep the space in the back and lose the space that you never use anyways. Just need to check if the seats still fold down (I think that there is enough room).

So when are you going to add this so that the rest of us can copy it :)

I think that I will wait until the summer ends before I tackle the dual battery. I'm always busy going away on weekends to devote the time this project needs.

Originally posted by ChuckH

has anyone else thought of this or am I the only one coming up with silly ideas?


Ahh...glad to see I'm not the only silly-minded fool out there: see this link! (http://www.automotiveforums.com/vbulletin/showthread.php?threadid=3694&pagenumber=2) & read the third post down:D:D:D.

Originally posted by xterrabull

Ahh...glad to see I'm not the only silly-minded fool out there: see this link! (http://www.automotiveforums.com/vbulletin/showthread.php?threadid=3694&pagenumber=2) & read the third post down:D:D:D.


Ha...guess I missed that post or didn't read it carefully! Others are right about the water factor and such, but I still think it could possibly work if properly sealed for the folks that dump their bumper. With an Optima I wouldn't think an accident would be much of an issue. Infact, the factory battery is probably more of an issue in the current spot due to the acid. Anyway, I'm not really thinking of putting a second battery in at this point...just thinking for others! :D

Moppie,

Weight in general is not much of an issue. What I was concerned about is placement of the weight. Almost all the folks who would want a second battery have winches up front already. Adding the bumpers and the winches alone puts huge amounts of extra stress on the front torsion bars and shocks. Adding a battery up there puts even more weight out in front of the front axle and the spot I'm talking about would also put the weight off to the right. So, as you could imagine, the right front of the truck could become more bouncy than the left side and maybe even upgraded torsion bars would not like the extra lbs. Just have to cover all the bases! :)

There is a "how to" article in the September 2001 issue of 4 Wheel Drive & Sport Utility on setting up dual batteries. For saving space they have an idea I haven't seen anyone mention. The article says that for your second battery you can use two Optima 6 volt batteries. I haven't investigated the situation, but maybe you could fit two 6 volt batteries under the hood easier than an extra 12 volt battery.

Originally posted by ScottG
The article says that for your second battery you can use two Optima 6 volt batteries. I haven't investigated the situation, but maybe you could fit two 6 volt batteries under the hood easier than an extra 12 volt battery.


Goth looked into that and then (IIRC) decided against it.

I did look into it pretty extensively, and was ready to place my order for the isolator, wiring, and batteries to do it, but when I realized the 6 volt cells cost as much each as the 12 volt ones, and you do reduce your reserve capacity a bit by running the two 6 volt batteries in series (as compared to one 12v battery), I lost interest. I still think it's the easiest way to get a dual battery setup into the engine compartment but since the prime mounting location ended up being where I mounted my QuickAir2 air compressor, the project is on hold indefinitely for me.

Maybe one of these days...but I'm certainly willing to let someone else try this mod first if they feel like it. If you have any questions about it though feel free to ask...as MT mentioned I did scope this option out pretty well. Warmonger also knows quite a bit about the whole dual battery setup as well...

As I have said to several people in regard to my dual battery setup, you better have the time to devote to it. It is not a project for the non-mechanically minded! I don't regret doing mine at all. But be prepared to do a lot of research and planning to make it work on an Xterra. They make bolt-ons for a Jeep, but us Nissan folks are on our own.

Originally posted by warmonger
As I have said to several people in regard to my dual battery setup, you better have the time to devote to it. It is not a project for the non-mechanically minded! I don't regret doing mine at all. But be prepared to do a lot of research and planning to make it work on an Xterra. They make bolt-ons for a Jeep, but us Nissan folks are on our own.

what is the difference between the bolt on kits for a jeep and what needs to happen for the X? i remember us talking a little when we were on the plant tour, but because of my lack of electrical knowledge i still didn't get it enough to say i understand the issues.

my questions would be, If i were to buy the kit from PNW power that is for the TJ, why couldn't I modify the cable lengths a bit and put it on the X? If I were to put the battery in the arb or in a waterproof tray up under my skid plates wouldn't that work? If i recall correctly from our conversation before the added cable lengths posed a problem for you, but you were going all the way to cargo area with yours, which i am not going to do.

The problem is where to mount the batteries. Space under the hood is at a premium on an Xterra and Frontier. They just didn't leave enough room to mount a spare battery. The TJ kit mounts under the hood by replacing the factory battery box. The Nissan box is welded in place. If you have an XE, you are better off than those of us with SEs, but not a whole lot. I had to relocate mine to the position they are in because of the size of the compressor I planned on using. Others may not have to worry about that, but they will be breaking new ground. Hopefully they post some info about it on the Internet. Mine was so complex, I just didn't feel like patching the whole 2 month process together. Not to mention the fact that due to the complexities of my creation, I wasn't comfortable saying others could emulate it. You would have to have an above average mechanical and electrical ability as well as a service manual and the patience of Job.

http://www.beatdriven.com/xterra/4x4lo_mirror/dual_battery/overall_1.jpg

http://www.beatdriven.com/xterra/4x4lo_mirror/dual_battery/yellow_top.jpg

About two full days of installation work...mainly figuring stuff out. Cutting the cables and crimping & soldering the ends took a good while as well.

Not that they'll ever see it, but the folks at WranglerNW, and especially the friendly guys at the local Batteries Plus helped me out a good bit. My favorite part was the little "positive" and "negative" labeled heatshrinks Stan @ WranglerNW added to my order. :)

If I can't come up w/ a better securing method than zipties soon, I'll make the hike up to one of those friendly folks who live north of me who own lots of tools and have a knack for fabrication...I have an idea for a replacement tray that could be fabricated in case anyone else ever does this mod.

I think that getting some fab'ed up would be the best bet in the long run.
This is something that will have to last a long time and take a bit of abuse (I have seen the pics :) )

I just cannot wait for the write up so I can add this to my X
:)

Inspired by these pictures, I got a second battery jammed into my
Xterra this weekend. I had to re-locate the coolant overflow tank, rotate the existing battery 90 degrees, and lift some some sheet metal so it could slide as far into the corner as possible. Then the Optima Yellowtop slid in pretty easily, albeit vertically. I'd already wired for a 500W power inverter which is located under the passenger seat. I even put a standard wall outlet in on the back of the center console. Now that I've got the 2nd battery, I'll have to order a Hellroaring battery isolater -- turning out to be a fairly expensive project!

Sounds like quite the project. Got any pics? I know lots of people that want to figure out how to do this but just can't find room.

Here's a picture -- looks very similar to the previous one! I've since installed a Hellroaring isolator. So far, so good! If anyone has questions, send me a note.

Nice. I'll have to look in my engine compartment for a before view.

Have you considered joining PNWX?

im not sure if anyone has suggested this before but couldnt you replace the glove compartment with a second battery?

probly a stupid idea, but being 16 im new to this stuff...

by the way- what is a second battery for?

Originally posted by killer4605
im not sure if anyone has suggested this before but couldnt you replace the glove compartment with a second battery?

probly a stupid idea, but being 16 im new to this stuff...

by the way- what is a second battery for?

Uhhh open the glove box! Then look what is behind it!:bloated:

I got one of these really cool DVM's from Datel, about $30. It monitors the voltage on the second battery I installed. The really cool thing is I found it's an exact fit for that empty switch next to the rear wiper button!!!! Part Number DMS-20LCD-0-DCM

I like this for my voltage and oil pressure, easier to see at a glance. The lower one is voltage.
http://www.pnwx.net/gallerytest/Gauge-pods/gaugepods3.sized.jpg

Dual Battery Woes


I've got two batteries in my car, connected together with a Hellroaring battery isolator. One battery is a standard car battery. The other, isolated battery is an Optima Yellowtop. While the car is running, the alternator,both batteries and all the loads are all tied together. When the car is off, the isolator seperates the deep cycle battery and the loads connected to it from the car's starting battery.

Connected to this second battery is a computer which draw about 3 amps at 12 V. My 'carputer' is in standby mode most of the time, except while driving, and perhaps 20 minutes each day when it's running off of the isolated battery.

My problem: After about 4-5 months of operation, the Yellowtop has a dramatically reduced capacity, and drops below 11 volts after just a short time (20 minutes) of use with the car off.

Any ideas on my problem? I've actually had this problem occur twice now. The first time I thought it was just a bad battery.

Someone posted this on another forum.....

The Optima Yellow top battery is a Deep Cycle battery. These batteries are designed to be charged then discharged. These batteries use a thinker plate and thinner Active Paste layer than your standard automotive Optima. Each time you charge the battery, you consume some of the paste.

Now, in a situation like a camper or other system where the battery is fully charged than used as a power reservoir, you consume a small amount of this paste during your charge cycle and a little during your discharge. Usually this is done "not so often" so this paste lasts a decent amount of time.

In a car, your battery is in charge mode whenever your car is running. I know there are regulators and what not, but trust me, your car is constantly charging your batteries. During this charge cycle, you are consuming this paste layer. And since this paste layer is much thinner (with thicker plates) than the standard automotive Optima, you have a much shorter life cycle with your battery.

Sure, the capacity is attractive, but you will suffer with a shorter life. I have always ran standard automotive optimas and never had a problem. If you do want some extra capacity, use the Blue Top Optima. It is designed better for continous charging.

3 amps is an excesive draw in the automotive industry and no battery will hold up to that type of constant draw usually, especially after the engine is turned off (20 minutes????). I have dual batteries in mine (a Red and Yellow top) that have seen constant use for almost 3 years with only an isolator failure to lay claim to. The secondary battery runs my winch, my on-board air system and aux lights. You might want to take a close look at your electrical system and if that 3 amp draw is all that is causing your problem, set a shut-off for it after the engine is turned off. A blue top will last longer, but is going to also suffer from shorter life courtesy of your excessive draw.

Blue tops and Yellow tops have exactly the same performance. The only difference is the post style. Oh and one is Blue and the other is Yellow. :D