Dual Batteries

[BrooklynBay]

I have a dual battery set up with an isolator in my 88.

 

[Donner]

Mpg?

Dual batteries with proper isolation, can be a real lifesaver. However, consider the extra weight involved.

On my boat, I have three batteries ( Optima ), one each for only cranking the motors and one for the electronics ( 2 VHF radios, color fathometer, radar, chart ploter, loud hailer ) and lights.

this affects the mpg? (it sounds like it should be an automatic mod if all of this additional electronic equip is being added) And it's okay to have two different batteries, like an Optima and a Die Hard?

I have a dual battery set up with an isolator in my 88.

You have pics to share? what are the benefits? Any issues with the set up?

 

[aldive]

this affects the mpg? (it sounds like it should be an automatic mod if all of this additional electronic equip is being added) And it's okay to have two different batteries, like an Optima and a Die Hard?

Are you referring to the boat or a truck?

 

[kert0307]

I've got dual batteries in my 2000 sport. Optima red top up front for starting and normal functions, and an off brand deep cycle in the back for the stereo, 3 130watt lights, and my inverter. The 2nd battery is strapped down in a plastic battery box in the cargo area hidden behind my sub box. I'll see if I can find pics or my thread somewhere...



edit here's the link to my setup...
http://www.explorerforum.com/forums/showthread.php?t=194271&highlight=dual+batteries+battery

 

[Donner]

Trick question

Are you referring to the boat or a truck?

The boat would be knots per gallon, no?

It seems like the boat would be affected more than a land vessel... but the car would notice that extra battery?

 

[Donner]

How's it fastened down?

I've got dual batteries in my 2000 sport. Optima red top up front for starting and normal functions, and an off brand deep cycle in the back for the stereo, 3 130watt lights, and my inverter. The 2nd battery is strapped down in a plastic battery box in the cargo area hidden behind my sub box. I'll see if I can find pics or my thread somewhere...



edit here's the link to my setup...
http://www.explorerforum.com/forums/showthread.php?t=194271&highlight=dual+batteries+battery

No problems with tipping or anything?

 

[kert0307]

No problems with tipping or anything?

I assume you mean the 2nd battery. It has a ratcheting tie down around it (it's in a plastic case) going to a tie down point in the floor of the cargo area. I've taken it off road at a park in Il, and haven't had any problems.

 

[aldive]

The boat would be knots per gallon, no?

No!. Knots is a measurement of speed, not distance; One knot equals one nautical mile per hour.

The mileage measurement would be nautical miles per gallon.

 

[Donner]

I thought I gotcha!

No!. Knots is a measurement of speed, not distance; One knot equals one nautical mile per hour.

The mileage measurement would be nautical miles per gallon.

Well, from all of this input, a second battery should be considered a part of any serious modifications up front. If all of you have a second battery, it would be great advice to follow.

 

[Stic-o]

And it's okay to have two different batteries, like an Optima and a Die Hard?

You can't run a old and new (or of different age) Optima, they will take each other out

 

[Donner]

Thanks!

I will get two new of the same brand... discussed this with fabricator, no problem. But for me, $$$, will wait, groceries first.

This is one vehicle they are working on now... they said race fans would know whose prerunner car this is...

 

[brianjwilson]

Yes, extra weight, blah blah.
I'm not concerned about dragging around extra weight, I already carry lots of tools and recovery junk with me all the time anyway. I'm not so concerned about mileage as long as it is reasonable.
It's bad to mix batteries if they are connected together. The new one will drop down to the voltage of the old battery. I don't believe this is the case, however, with an isolator. Feel free to correct me if I'm wrong, but it should be completely fine to run different types of batteries with an isolator.

 

[Exploderpilot]

yes, with the isolator you can use different batteries.

 

[Donner]

I will go on theory... at the cost of two new batteries.

Yes, extra weight, blah blah.
I'm not concerned about dragging around extra weight, I already carry lots of tools and recovery junk with me all the time anyway. I'm not so concerned about mileage as long as it is reasonable.
It's bad to mix batteries if they are connected together. The new one will drop down to the voltage of the old battery. I don't believe this is the case, however, with an isolator. Feel free to correct me if I'm wrong, but it should be completely fine to run different types of batteries with an isolator.

I would just say that if it's for safety and reliability, hook up two new batts that are the same kind... I see it as changing the batts in a flashlight, you change them all at the same time. This being a project, it would wise to do what the others have suggested - for me, anyways. The fabricator said an isolator would be involved, but for me, two new batteries.

MPG I don't watch, but it's good advice, good to know.

 

[foxy]

Guys , I have duel batts in my 9/99 with the 2nd batt in a box in the rear .I run a 40 liter Engel frige freezer when of road and also for shopping , A compressor, extra lighting when camping out and also for jump starting my girl if the main goes flat . Also added a 200 amp alternator because I run my subwoofer off the 2nd battery as well .My system is a Piranaha which will charge the main first then the 2nd one .it also comes with a guage telling you how well the batts are charged . My cabling is 5/8th's copper insulated with a master switch to turn on my batt to jump start with a surge arrestor as well in line .hope this can help certainly worth doing Cheers Barry

 

[foxy]

just a footnote the main battery is not standard but classed as a commercial one slightly taller and has more grunt also the 2nd one is bigger again and it can tolerate being flattened wheras the main if you flatten it to often you'll kill it .2nd one has if I remember right 720cca's (cold cranking amps) Cheers

 

[Donner]

Thank you Foxy... this will be a nice project.