battery

say i wanted to add another battery to my car and put it in my trunk to run my sound system. how would i do this. what would i need to buy. how much would this cost and can i get something like this done at a car shop. give me info...

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2005 Ford 500 SEL. 3 Kicker CVR 15"s. 2000 watt Quantum Audio AMP.

Your going to need a Battery Isolater , this allows the alternator to charge both batteries but only lets the one original battery to start the car. You dont want 24v going to the starter. You may want to look into upgrading your alternator , depending on what you have or what you will be running from the 2nd battery. (How many amps you'll be pulling) Of coarse you'll need the cables to reach and a decent battery box wouldnt hurt.

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99 F-one fitty
Pioneer Premier H/U
Alpine EQ
Kicker 1200 amp
4 Kicker comp 10s
6 kicker SS65.2 components

curious here..i have 2 batteries in my truck and no isolator between them. i was told by multiple people that i didnt need them as long as i drove my truck often and didnt use the stereo with the truck off. with just a power wire between them, and each grounded to the truck, im only getting 12 volts in the system right? multimeter only shows 14.5 with the truck running..what is the popular opinion on this?

As you can see in this past thread, there are differing opinions on what is the best way to use multiple batteries.  Besides that thread, you can do a search through the forum archived threads and make your decision based on the arguments for each way.

Your statement "as long as i drove my truck often and didnt use the stereo with the truck off" is the drawback to keeping an isolator out of the picture.  And yes, your voltage is correct.  The truck wouldn't run and the audio system wouldn't work if it were wrong.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

you will not get 24 volts with 2 batts. I run 2 batts with no isolator. I have no trobles at all. I play my system for a long time without the truck running. Big trucks don't use isolators. my buddy's UD tow truck has 2 batts no isolator, and my other buddy's 18 wheeler has 6 batts with no isolator.

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Big Dave

u dudes are really helpful thank you all. i got a few questions though hope i dont confuse anyone.

 Now stevdart i read that past thread. Now would u agree with the dude that said use the same exact battery. if so the battery i have is brand new but its not a yellow top or nothin. how would i mount the second battery in my trunk, do i need to construct a  box to install it in.

also when wiring the batteries in parallel, what guage wire do i run. parallel wiring would be red-power wire to red side of battery and black-ground wire to black side of battery.  i dont ground the black wire to metal on the4 car right?

as i read in the past thread, the someone stated that when installin two batteries have a fusebox close to the first battery  and another close to the second battery is this true and needed?

can i run these two batteries off the factory alternator. i dont know the specs of the alt. i cant look right now cuz my car is currently at the paint shop.

i think thats all my questions...help me out, as u dudes do so well.. are there any diagrams to help me get a visual...

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2005 Ford 500 SEL. 3 Kicker CVR 15"s. 2000 watt Quantum Audio AMP.

thanks barqer all info is helpful. around how much do the yellow top batteries cost. the one in the bed how is it installed. is it jus braced to the bed or is it installed in a custom box..whats the difference between yellow top batteries and reg. car batteries..

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2005 Ford 500 SEL. 3 Kicker CVR 15"s. 2000 watt Quantum Audio AMP.

You do not need yellow top battery, (personal feelings speaking, the red-tops are better spec-wise for car stereo anyway, but I don't really want to go into that right now...) or any other specialty type of battery. Just remember, if you add another battery, just make certain it is the SAME as the front one. As far as the cable size between the two, it only has to be big enough to support the current capacity of your alternator. If you have a 150 amp alternator, use a number 4; 200 amps need a number 2... and on and on. Make certain you fuse BOTH ends of this cable for safety, also!

As far as an "enclosure"? Not really necessary, except for appearance. As long as it is strapped down, so it can't fly around in the event of an accident, (or grow legs) you should be good to go.

The Optima (yellow, red, Rockford...) batteries are very different from standard car batteries in the way they are constructed. A standard battery uses flat plates that are separated by paper, with a liquid electrolyte (the acid) surrounding the whole mess. These are adequate for most applications, but are VERY unhappy when discharged more than 20% (somewhere around 10.4 volts). Once this happens, the life of the battery is reduced by as much as 50%, and it will NEVER provide full output current again. They also do not like heat - the kind of heat under your hood... (Hmmm. I wonder why they don't use different battery technology for cars, yet?)

Oh, wait! This is where the Optima "Spiral Cell" technology comes into play. (Don't I sound like a commercial? LOL) The way the Optima batteries are built, is they take the lead plates, and roll 'em up with a paper separator, but then they saturate the paper with the same acid, but leave none free inside the battery. This is why you can use them in any position. Because of the rolled technology, the plates will not warp or crack (as easily) with abuse, such as (semi)deep discharging, or high temperature environments.

On to the differences between standard (red-top) and deep cycle (yellow-top) batteries. NOTHING. They are the same, save the THICKNESS of the plates they are built with - deep cycle being up to 25 percent thicker. Because the current a battery can produce comes from a chemical reaction, the number of plates (or total surface area of the plates - 25% thicker means 25% fewer plates, means 25% less peak current...) will DIRECTLY affect the amount of peak current it can produce, because you have fewer plates, right? If you have a battery case of X volume, and you place battery plates within it, it will make X current, right? If you have the same battery case, but you place thicker plates in it, you will be able to get LESS peak current, right? Now, red and yellow top batteries are the same size case... the deep cycle version, (yellow top) has FEWER plates, right? Which one is better for CURRENT? The red top, right? What does a car amp need to produce power? Current, that's right. Now which one will you choose? Me? I'm saving the cash, and getting a better battery for my application, and gonna buy the red top.

Now, before somebody argues with me, I will also add that the rolled cells prevent the warping caused by deep discharging, WITHOUT the plates needing to be any thicker - so I don't NEED to buy a deep cycle battery... Optima already gave me the deep(er) cycling capacity when they rolled the plates. Also, I never run my batteries to that deep a discharge cycle anyway.

No, I am NOT a salesman for Optima, I am a network administrator in the health care field. BUT, I have 16 years of formal electronics experience and training, and I take everything the salesman tells me with a grain of salt... I'm their WORST nightmare - I used to BE in sales.   BWAHAHAHAHAH!

Happy Halloween!

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

im need help understanding this. i read up above its not about the wattage, its about amperage. so the amperage is what tells you how powerful an amp is. i have two 1000 watt amps with two 40 amp fuses a piece. i have one more 400 watt amp wit a 30 amp fuse. i currently disconnected my system becus i put my car in the paint shop but when i had my system hooked up for a couple of hours jus to see how it sounded, my lights did dim. one of my homeboys told me i need a cap, like 3.5 farad. ive been reading its not about the cap though its the alternator.  what should i do before i hook my system back up. what size fuse do i need in my 4 guage wire kit. do i need another alt. if so what amperage. do i need another battery. help me wit some info..

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2005 Ford 500 SEL. 3 Kicker CVR 15"s. 2000 watt Quantum Audio AMP.

wattage EQUALS voltage TIMES amperage - It's Ohm's Law again!

40 amp fuse + 40 amp fuse = 80 Amps
80 amps times 14.4 volts = 1152 watts

I have a real tough time believing that your amplifiers are 87 percent efficient. Are they digital? If not, they are lying to you, they are NOT a 1000 watt amplifier. Fill us in on the brand name of them, and we will let you know...

A cap WILL NOT FIX YOUR PROBLEM!!! Let me restate that A CAP WILL NOT FIX YOUR PROBLEM!!! You must start with your alternator. Then multiple batteries, THEN add a cap, if you feel so inclined. And yes, a 3.5F will probably do what you "need" it to do, but only after addressing the power SUPPLY first.

A #4 cable is safe, fused at 150 amps. As far as the larger alternator, get the biggest thing you can afford that will go in your car. You won't be sorry.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."