Author Topic: Additional Battery  (Read 2260 times)

Offline jonnypolish

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Additional Battery
« on: 01 September 2010, 21:37 »
Haven't covered this before in all my time, Have seen them here and there in other cars but am at a bit of a loss when it comes to sorting one out for myself!
I am looking into this avenue of installing an additional battery in the boot to power my sound system so there is less clutter going through the car and the engine then has its own dedicated power supply!
I'm running 6k+ Watts on the subs and a variation through the components that the lights dim GREATLY at night, so i have resorted to leaving the stereo off at night!

My Questions is:
1) Do i need another alternator? or can i use the existing one to run both batteries?

I look forward to your replies,
Many thanks, Jon
 MK2 VR y0!

Offline Ben Lessani

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Re: Additional Battery
« Reply #1 on: 01 September 2010, 21:42 »
You'll need a split charging system.

Better off buying a bigger alternator and KISS.

Offline Ben Lessani

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Offline jonnypolish

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Re: Additional Battery
« Reply #3 on: 02 September 2010, 19:51 »
That EASY! Cheers mate!
May Look into the Larger alternator route,
I take it that both batteries will be receiving the same charge? or a slightly lower one going to each?
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Offline emery1990

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Re: Additional Battery
« Reply #4 on: 03 September 2010, 17:52 »
Looks like its just running the battery in parallel  so would receive the same voltage

Offline Ben Lessani

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Re: Additional Battery
« Reply #5 on: 03 September 2010, 18:00 »
Looks like its just running the battery in parallel  so would receive the same voltage

It is, but it regulates charge level independently.

Offline jonnypolish

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Re: Additional Battery
« Reply #6 on: 03 September 2010, 18:42 »
Cheers lads! The info is much appreciated!
 MK2 VR y0!

Offline Diamond Hell

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Re: Additional Battery
« Reply #7 on: 03 September 2010, 21:05 »
Buy a marine split charge system - much better quality.
Just because you're offended doesn't make you right.

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Offline jonnypolish

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Re: Additional Battery
« Reply #8 on: 04 September 2010, 08:25 »
Cheers DH, Will get onto it today!
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Offline Sazbard

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Re: Additional Battery
« Reply #9 on: 04 September 2010, 09:29 »
Haven't covered this before in all my time, Have seen them here and there in other cars but am at a bit of a loss when it comes to sorting one out for myself!
I am looking into this avenue of installing an additional battery in the boot to power my sound system so there is less clutter going through the car and the engine then has its own dedicated power supply!
I'm running 6k+ Watts on the subs and a variation through the components that the lights dim GREATLY at night, so i have resorted to leaving the stereo off at night!

My Questions is:
1) Do i need another alternator? or can i use the existing one to run both batteries?

I look forward to your replies,
Many thanks, Jon


Firstly, is this 6k rms power? or MAX power? If it is a geniuine 6k then you should be looking at an upgraded alt and battery in the boot.
You don't really need a split charge system, this is more for if you play the car with the engine off, it splits the batterys so you only drain the rear battery and can start the car again without worry about flattening the front one.

What amp, or amps are you running??

I presume you have run 0 guage from the front to the back and used a fused distro block with 4 guage coming out?

Dimming lights usually mean you haven't done:

1. Battery to ground (In your case  use 0 guage for this)
2. Alt to battery (you should be ok with 4guage for this)
3. Check that alt ground is all cleaned up.

Make sure your earth point in the boot for the amps is all cleaned up nicely.