Adding a second battery

Printed From: the12volt.com
Forum Name: General Discussion
Forum Discription: General Mobile Electronics Questions and Answers
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=26728
Printed Date: May 04, 2024 at 10:14 PM

Topic: Adding a second battery

Posted By: madeinarg
Subject: Adding a second battery
Date Posted: February 18, 2004 at 1:57 PM

I Have a 91 Honda Civic in which I am installing one nice, powerful sound system. The stock battery is verry small so I decided to install a secondary battery in the back near the amp so that I will have more Amps to run the system. Does anyone have any ideas on whether this will work of not, and how I can keep the second battery charged?

Replies:

Posted By: devilsquid
Date Posted: February 18, 2004 at 2:49 PM

the battery will be charged just by being connected to the primary battery. you will need a bigger alternator to keep up, and if you dont want the system draining both batterys, then you will need an isolator. (recommended)

you also need to install the battery in a manner that it is sealed to the interior of the car, but vented to the outside as batteries produce toxic fumes.

hope this helps!

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Posted By: forbidden
Date Posted: February 18, 2004 at 4:08 PM

Unless he has a gel cell battery like an Optima yellow top, there is no need to vent it to the exterior like a normal battery and no danger to the occupants as there is no acid to spill.

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Top Secret, I can tell you but then my wife will kill me.

Posted By: nunogtp
Date Posted: February 20, 2004 at 8:18 AM

madeinarg wrote:

I Have a 91 Honda Civic in which I am installing one nice, powerful sound system. The stock battery is verry small so I decided to install a secondary battery in the back near the amp so that I will have more Amps to run the system. Does anyone have any ideas on whether this will work of not, and how I can keep the second battery charged?

the best thing to do is to add a second battery. i ran three optimas in my yukon denali. i suggest you take out the front battery and replace it with a optima red top. upgrade the 8gauge wire from the alternator to a 4or 2 gauge, add the extra battery in the truck preferably a yellow top, you will want to install a battery isolator. Don't get a battery relay because that will allow the car to use both batterys to run the electrical and the system. the isolator will seperate the batterys so that they both charge at the same time but only the rear battery runs the stereo. this is a gaurenteed way to not have your lights dim and completely seperate the stereo from the car

Posted By: madeinarg
Date Posted: February 20, 2004 at 1:10 PM

thanks for the responses, they do really help. i have been working on my system for a little while now, making sure that every little thing is in its right spot. i even made my own crossovers with the perfect calculations to obtain maximum power, the sad thing is, last night someone broke in my car and took my stereo. so now a stereo is the next thing in my shopping list! again, thanks for the responses!