Fitting a second battery?

[Ry' N Jen]

What is the general consensus when it comes to installing a
second battery?
We already have an Optima Red Top, but I would like to add
an additional Optima Blue Top to run camp accessories like
our two portable 12 volt coolers as well as electrical lighting,
TV/DVD player, blender, etc.
I would use a 120 amp battery isolator that I already have.

 

[loves_off_roading]

don't know anything about installing a battery but I recomend you get something other than a Mopar like a Diehard. Thats if you haven't gotten a Mopar yet.

 

[Powerslave]

I have HOW TO here on adding a second battery. You need an ISOLATOR, so only one battery at a time is being charged. They are VERY simple to use and install. The Isolator keeps them separate, and both charged at intervals as needed.

 

[Ry' N Jen]

I have HOW TO here on adding a second battery. You need an ISOLATOR, so only one battery at a time is being charged. They are VERY simple to use and install. The Isolator keeps them separate, and both charged at intervals as needed.

Thank you Powerslave.

Installing and wiring both batteries isn't the question.
I already have a 120 amp battery isolator. (Several actually! I run a Optima Red Top and Optima Blue Top in my '76 Mini.)

I just wanted to get feed back from "The others" regarding doing this!

More or less curious what people have to say about stuffing another batery
into/onto a KJ!

 

[LibertyTC]

That would be sweet to have 2 and an inverter.
I guess the safest place is under the hood for the second, and unless you remove the stock air box, where else could you mount it?

 

[Ry' N Jen]

That would be sweet to have 2 and an inverter.
I guess the safest place is under the hood for the second, and unless you remove the stock air box, where else could you mount it?

That's exactly where the second battery is going Tim!
Considering that the stock air box is the size of a battery anyway,
I am removing the factory air box so an extra battery can be placed
there.
I am currently fabricating an air box that works with the Snorkel
I am building.
It will fit snug. On the inner fender (Close to the fire wall on the
passengers side.)

 

[HoosierJeeper]

Does sound like a real tight fit...

Ryan, since I think you're the first one to do this, maybe you could do a How To with pics?

 

[Ry' N Jen]

Somebody in the family let it slip out that I was getting a Yellow Top for Christmas!
I guess I'll just have to wait and see...
If I do get one, I'll give a how to a try!

 

[kb0nly]

I thought about putting a second battery in the back in a box, you can get a box with a vent tube, run the vent tube and the battery cables down through the large floor grommet where the trailer wiring goes down.

The only thing i don't like about the isolators... You get a forward voltage drop from the diodes used. Usually at least a half a volt, but sometimes as much as a volt, the problem here is you never bring the batteries up to full voltage with one of those diode isolators and you need to increase your alternator output to compensate. I would guess the KJ, since its a computer controlled charging system, would sense the battery voltage is lower and compensate by increasing the output, but then your alternator is just working harder.

I prefer to use a continuous duty high current relay made for this application. No voltage drop and the overall function is better. With the diode isolator all your doing is splitting your alternator output between the two batteries. With the relay you connect the positive of each battery to each side of the relay and the relay coil gets connected to an ignition switched source. Now when you turn on the key both batteries are connected, so when the engine is running both get charged, but when you shut the key off the second battery is disconnected and you can run all your accessories off of it.

There is another added benefit here... I used to have this setup in my S10, i had all my ham radio gear on the second battery to avoid draining the main battery when sitting and talking with the engine off. Lets say your main battery goes dead for whatever reason, you can give yourself a jump start. Turn the key on, if the main battery has enough power to at least actuate the relay then the second battery will be connected and it will start transferring to the main battery, which will keep the relay switched and now you can just sit and wait a few minutes and then start.

If the main battery doesn't have enough power to actuate the relay all it takes is a short jumper of wire from the secondary battery terminal to the relay coil positive, turn the key on, then use the jumper wire to actuate the relay for a few minutes.

Now whether you use the relay or the diode isolator its best to also add some circuit protection. I used a 60 amp circuit breaker with manual trip at the second battery, this way if there was any short in the run from the battery forward it would protect it, also if the second battery became a dead short it would protect the main battery and alternator from feeding a dead short.

To be really safe its also nice to put a breaker between the main battery and the relay. This way you have it protected from both ends and you can hit the manual trip on the breakers and shut off everything in the event the relay has a problem. Its also important to have that underhood breaker as a second battery disconnect in case of an emergency.

So why 60a breakers? Well in my case i used an shunt and ammeter and found that with the engine running and all accessories turned on, on my S10 at the time, i had roughly a 50 amp draw. So i designed the system so the second battery could at least feed everything if it was needed to with a slight overhead for safety.

 

[LibertyTC]

It will be the only "Tripple How TO"
Make your own Snorkel to Create More Room For The Second Battery, Then Install Inverter, to Power The Entire Campsite!!
I know who's KJ I want to borrow, when I go camping...nana.gif

 

[CRD Joe]

I would like to see that installation.

 

[Powerslave]

If you use a SEALED battery inside, you won't need a VENT tube. Gel Cells are completely sealed, and they are great, and are designed for loads at longer intervals. I also though the Energizer ones were sealed as well?

 

[tjkj2002]

If you use a SEALED battery inside, you won't need a VENT tube. Gel Cells are completely sealed, and they are great, and are designed for loads at longer intervals. I also though the Energizer ones were sealed as well?

No automotive battery is 100% sealed,even a Optima has vents still.

 

[kb0nly]

No automotive battery is 100% sealed,even a Optima has vents still.

Exactly...

A Gel Cell is actually rated as a low gas battery, but it does still gas off a bit when charging, just not as much as a typical wet cell battery.

 

[Powerslave]

The GEL cells are 100% sealed, that I know for sure. The places that LOOK like you add chemicals are glued shut, and sealed around them, and on top of them, They are used in the handicapped power chair and other power use devices. The batteries are charged IN HOUSE, not outside. These (the big ones) work well as auto batteries too. My uncle used to work for a place that services the devices, and they throw the batteries out every six months, no where NEAR the end of their life-span (regulation thing). HE put one in his Buick SUV, worked fine, and sold it with that in it. They are designed to run with a steady load. With one of these Gel Cells, you could crank the motor till the started burned out, that's how good they are, AND expensive. They are 100% sealed, and there are 100% sealed lead acid batteries too.

There are AGM (Absorbent Glass Matt) batteries that are also 100% sealed.

Optima says their batteries are completely sealed: Optima batteries are true "Zero Maintenance" - All Optima Batteries are completely sealed, absorbed electrolyte design means OPTIMA Batteries won't spill, leak, or corrode - it's the safest, cleanest battery on the market. They can be mounted in any position - sideways, or even upside down. It can't have VENTS if you can mount it in ANY position, then it would leak out the vents if you turned it upside down. No, these are 100% sealed batteries, you can call them yourself and ask. I know THREE people who have them inside their cars, they produce no fumes when charging.

 

[OneOneNiner]

Here's my setup in Fulltimer's lost thread.Only difference is that I replaced the red with a yellow.Works great.This is my third setup like this(jeep,56&85 ford picups) with all sorts of battery configurations.
http://www.lostkjs.com/forum/phpBB2/viewtopic.php?t=32018&start=20

Sorry Bird.

 

[Ry' N Jen]

The GEL cells are 100% sealed, that I know for sure. The places that LOOK like you add chemicals are glued shut, and sealed around them, and on top of them, They are used in the handicapped power chair and other power use devices. The batteries are charged IN HOUSE, not outside. These (the big ones) work well as auto batteries too. My uncle used to work for a place that services the devices, and they throw the batteries out every six months, no where NEAR the end of their life-span (regulation thing). HE put one in his Buick SUV, worked fine, and sold it with that in it. They are designed to run with a steady load. With one of these Gel Cells, you could crank the motor till the started burned out, that's how good they are, AND expensive. They are 100% sealed, and there are 100% sealed lead acid batteries too.

There are AGM (Absorbent Glass Matt) batteries that are also 100% sealed.

Optima says their batteries are completely sealed: Optima batteries are true "Zero Maintenance" - All Optima Batteries are completely sealed, absorbed electrolyte design means OPTIMA Batteries won't spill, leak, or corrode - it's the safest, cleanest battery on the market. They can be mounted in any position - sideways, or even upside down. It can't have VENTS if you can mount it in ANY position, then it would leak out the vents if you turned it upside down. No, these are 100% sealed batteries, you can call them yourself and ask. I know THREE people who have them inside their cars, they produce no fumes when charging.

Optima Batteries do have vents.

Does an OPTIMA battery ever gas?
When used with a properly regulated constant voltage charging system (such as an alternator) the OPTIMA will usually not emit hydrogen gas. However, gassing can occur when charging at higher voltage levels or in extreme high temperature conditions. In automotive applications this typically will not happen if the alternator/regulator stay below 15 volts.


Unfortunately, OPTIMA does not offer an exact-fit replacement battery for every application. You can measure the dimensions of your existing stock battery to see if there’s an OPTIMA that will work for your vehicle. Below is a link to the product specification page where you can find exact dimensions for all OPTIMA batteries:

View our products spec pages to find the exact dimensions.

YellowTop
http://www.optimabatteries.com/optima_products/yellowtop/specs.php

BlueTop
http://www.optimabatteries.com/optima_products/bluetop/specs.php

RedTop
http://www.optimabatteries.com/optima_products/redtop/specs.php

Alternately, you can check the Internet enthusiast forums for your vehicle to see how others have done custom applications with OPTIMA batteries.

If you are using an OPTIMA battery in a custom application, it is important to consider the following:

1.Hood Clearance – There should be at least ¾” clearance between the top of the battery terminals and the underside of the hood.

2.Trunk/Interior Mounting – If your battery is mounted inside the passenger compartment or trunk (common in many European makes), the battery must be vented to the outside of the vehicle. OPTIMA group 27, 51, 78, 34C, and 31 batteries all have ports for connecting a vent hose.

3.Side Terminals – OPTIMA 34/78, D34/78, 75/25 and D75/25 batteries have both top and side terminals. If you are using one of these batteries in a vehicle that uses the top terminals, it is important to ensure that the side terminals can not come into contact with anything metallic (for example, the firewall or fender well), thereby causing a short. We suggest keeping the post protectors on the terminals you are not using. Do not connect a winch to the side terminals.

4.Battery Modifications – Cutting, drilling, trimming or otherwise modifying your OPTIMA battery may present a safety hazard and will void the warranty.

5.Mounting – Your Optima battery must be securely mounted. The terminals are not intended to be used to secure the battery. Using the terminals in this way will damage the battery and void your warranty.


The above by the way comes right from the Optima Battery website!

 

[Powerslave]

They are not vents, they are valves (technicality? I'll take it). It says overcharging CAN CAUSE the valves to open. SO, if you install one upside down, or sideways; and a valve happens to open? What else is coming out?

They will not overcharge in a dual battery setup in a car, with an isolator. Once it is charged, the isolator (or similar setup) switches back to the primary battery. You're quite safe with these inside a vehicle, unless YOU did something wrong.

When placed on a manual charger, where there is no protection for overcharging, well, there ya go. The optima batteries are the safest ones out there, along with the Gel Cells.

 

[kb0nly]

They are not vents, they are valves (technicality? I'll take it). It says overcharging CAN CAUSE the valves to open. SO, if you install one upside down, or sideways; and a valve happens to open? What else is coming out?

They will not overcharge in a dual battery setup in a car, with an isolator. Once it is charged, the isolator (or similar setup) switches back to the primary battery. You're quite safe with these inside a vehicle, unless YOU did something wrong.

When placed on a manual charger, where there is no protection for overcharging, well, there ya go. The optima batteries are the safest ones out there, along with the Gel Cells.

Yes, the Optima batteries have pressure vents on them, they are like a spring loaded safety valve that will blow to release the pressure if it builds. But nothing but gas will leak out, or so i am told by the factory rep i know, the paste density in these batteries won't flow or leak out.

As for Gel Cell batteries, NONE of them are 100% sealed. They cannot be 100% sealed. Ask any manufacturer of large gel cell batteries. The sales rep that services the electric wheelchair demand here at the hospital gave me a long lecture when i suggested they were totally sealed. They have to be allowed to breath for differences in temperature and altitude, they basically have pressure equalizing valves in them. Yes they look 100% glued shut but they aren't. He pointed out on the batteries where the very small hole was around the places they were glued shut.

If you took any battery and sealed it 100% what do you have?? A bomb... Even NiCad and NiMH rechargeable cells down to the AAA size have vents on them. About the only battery that doesn't have venting on them is your regular old Alkaline battery, but only because they are not rechargeable. Want to see a battery explode? Put a Alkaline battery in a NiCad charger, its not just the current being forced into it, its the buildup of pressure from gas that makes it pop. You can take a rechargeable battery and seal the vent off and they will blow up to.. I know i've done it before.. LOL

 

[Ry' N Jen]

They are not vents, they are valves (technicality? I'll take it). It says overcharging CAN CAUSE the valves to open. SO, if you install one upside down, or sideways; and a valve happens to open? What else is coming out?

They will not overcharge in a dual battery setup in a car, with an isolator. Once it is charged, the isolator (or similar setup) switches back to the primary battery. You're quite safe with these inside a vehicle, unless YOU did something wrong.

When placed on a manual charger, where there is no protection for overcharging, well, there ya go. The optima batteries are the safest ones out there, along with the Gel Cells.

Look at the round six sided dashed circle with the grey sintered medium.
That is the vent to the left of the label. There is also one by the other
battery terminal.

VENTS not "Valves"!