SIMPLE Dual Battery Question

[ChrisR750]

Hi All,

I'm sorry, this is going to be extremely redundant, but you guys are all way over my head. I want to run a second battery simply to extend the amount of time I can run my stereo, interior lights, etc. without needing a jump. I understand an isolator only plus the battery is really the only things I need, and then wire them together through the isolator, and be done with it. Is this accurate? I don't want to have to re-wire my amp, stereo, etc. Will what I am proposing give me what I'm looking for? I have an '87 pretty much stock. Thanks in advance for tolerating my pedestrian understanding level!!

 

[BUDDY]

You could do that & it'll probably work fine for a long time.

However, there are other simpler & more robust ways to do the same thing.

Search google for "blue seas acr"

Or

"Billavista dual battery"

Post back up here if you have any other questions.

Later,
Buddy

 

[4X4HIGH]

Actually, running a dual battery isolator or ACR as Ryoken will suggest (either will work) would be the way to go BUT you would want to wire your stereo power (and any related items such as AMPs) to the Aux battery. If you don't wire the power supply to the Aux battery then what will happen is you will eventually kill the main battery (starting battery) and then you will have to run jumper cables from your main battery to your Aux battery in order to start the vehicle. If you run the batteries in parallel then you will increase the amount of "run time" before both batteries go dead but this will leave you without a "start" battery. Basically a dual battery system is good as long as you wire all of your accessories to the Aux battery so that you never drain your main start battery.

 

[badmix]

There are different ways to handle it. The above posts are pretty simple. How I have mine is like this. Im using a HELLROARING isolater. You can get the isolater to either use 2nd battery as an AUX or strictly as backup, which is what im doing.

How my system works, Im using Optimum batteries, all my stuff is hooked thru factory fuse panel and off my main battery, The 2nd battery is there for strictly backup. If i kill my main, I flip a switch and the 2nd one comes online. I have a switch that came with the kit that controls the 2nd battery

Position up combines the 2 batteries for winching and if my main is dead, both batteries receive charge from alternator

Position middle - both batteries are charged but 2nd battery is not effected by any accessories

Position down - 2nd battery completely out of the system and will not be charged.

My theory is this, I want a good battery incase my main goes dead. If you have dual batteries and you have a parasitic draw, itll kill BOTH batteries, in my system it wont do that, the 2nd battery is immune from that.

Wiring was pretty simple, Just ran pos. wire off starter to isolator and then wire off isolator to BUSS fuze and then onto Aux Battery and just ran Neg wire off battery to the frame.

 

[ryoken]

Hi All,

I'm sorry, this is going to be extremely redundant, but you guys are all way over my head. I want to run a second battery simply to extend the amount of time I can run my stereo, interior lights, etc. without needing a jump. I understand an isolator only plus the battery is really the only things I need, and then wire them together through the isolator, and be done with it. Is this accurate? I don't want to have to re-wire my amp, stereo, etc. Will what I am proposing give me what I'm looking for? I have an '87 pretty much stock. Thanks in advance for tolerating my pedestrian understanding level!!

apparently my reputation proceeds me....

my suggestion? spend a weeks worth of time searching and reading on "dual batteries" it's best if you REALLY understand what a DC system is comprised of, and how you want/can make it work for you... there are a couple "epic" threads on this, gone into serious detail if need be...

pro's and con's to all systems, from a simple paralleled battery to my ACR setup.. and yes, there are quite a few ways to go about this..

cheaper diode isolators can be had for as little as $25......

 

[dhcomp]

If you are worried about hooking it up wrong, i highly suggest you use a kit.

http://12voltguy.com/web/index.php?...ategory_id=10&option=com_virtuemart&Itemid=43

This is the kit i have, and am very happy with it. With this one, your AUX battery basically becomes your emergency start battery. That way, no accessories (lights, stereo, etc), have to be rewired....they all stay on the primary battery.

It allows you to automatically combine the batteries when teh key is on, or leave them isolated, or Emergency jump start yourself. Good luck!