Is a battery Isolator really needed?

[APitBullT 10+ year member]

I wanted to know if a battery isolator is really needed?

Well i have 2 batteries, one of them is under the hood and that one is an optima red top, and the second one i was planning to put it in the back and that one is an optima yellow top. The yellow top is not hooked up yet. ive been trying to get help on this problem but no one likes to talk about or help on this subject. Just give me your opinion if a battery isolator is really needed.

everything is in my signature if thats needed at all...

Click to read more...

 

[johnecon2001 5,000+ posts]

you should get one, most multiple battery setups have one.. those who don't.. not really sure why they dont.

 

[Logikalliquid 10+ year member]

You don't *need* one for it to work. The purpose of the isolator is so that you don't drain your starter battery while your playing your stereo with the car off. All the power comes from your 2nd battery.

 

[Randy Savage 5,000+ posts]

I've *NEVER* used one...and I've had at least one extra battery in my truck for 2 years now.

 

[APitBullT 10+ year member]

ok say if i dont have a isolator and i have both batts and my car is off and my music is playing, is it still going to drain my main battery even with the second bat?

 

[millerscents 10+ year member]

yep it will

 

[APitBullT 10+ year member]

then if you dont have an isolator, why the second bat?

 

[RCwhat 10+ year member]

more juice

 

[ngsm13 5,000+ posts]

I've *NEVER* used one...and I've had at least one extra battery in my truck for 2 years now.

Same story hear!

It's a waste of money...period.

NG

 

[btnhfan 5,000+ posts]

No isolator here. I have 2 batteries in the back, soon to be 4

 

[Logikalliquid 10+ year member]

Wow, I thought it was a rule to have an isolator with a multi battery setup(at least in any daily driver setup).

 

[jsloan10 10+ year member]

As I understand it when running more than 1 battery without an isolator the 2 or more batterys must be Identical in every way. If using different types and sizes of batterys an isolator is required.

Heres a snippet of info from an FAQ-

2.10 When should I upgrade my battery or add a second battery? [iDB]

======================================================================

The battery is most important when the engine is turned off, because it

supplies all of power to the audio system. The stock battery in your

car may not be up to the task of running a stereo with multiple (or

large) amplifiers if it can't supply enough current to the amplifiers.

Upgrading your current battery to a larger model may help solve the

problem because batteries like the Optima 800 offer a larger number of

cold cranking amps.

Generally, adding a second battery is great if you want to listen to

your stereo with the car turned off (and be able to start the car again

later!). This is accomplished using a dual-battery isolator: a device

which allows the second battery to be charged by the alternator, but

prevents the amplifiers that are connected to the second battery from

drawing any power from the main battery. Installing a second battery

may be done instead of upgrading the main battery.

 

[ntense702 10+ year member]

been using an exta battery for the last couple of months without an isolator and never had any problems, keeps plenty of juice flowing as is...

 

[Logikalliquid 10+ year member]

Sorry to threadjack, but its on topic:

Is everyone using the same batteries in there multi-battery setups?

Do you guys run the wire to the 2nd battery from the 1st battery or from the alternator? Does it matter?(I'm going to guess it doesn't)

 

[APitBullT 10+ year member]

Sorry to threadjack, but its on topic: Do you guys run the wire to the 2nd battery from the 1st battery or from the alternator? Does it matter?(I'm going to guess it doesn't)

yeah i also want to know this. How would you wire the batteries?

is there any pictures that give you and example (like the engine bay, the second battery all wired up)?