Installing a second battery

Has anyone ever attempted to install a second battery in their riviera? I would love to be able to run my stereo for more than 30 minutes without draining the battery enough to cause a no start issue.

Would the alternator be able to handle charging two batteries? How would I go about doing it? Would I connect them in series or in parallel? I'm thinking of keeping the current battery in the same location and mounting the other one in the trunk. I'd just like to get your opinions on this and how I should go about doing it. I've got a battery out of my old car that should work great for this, or I may get a yellowtop.

You must have a kickin system, or else a bad battery. I can run my system all day and still have enough juice to start it up.

Are you running a stock battery? Their CCA is very high compared to most. It's a big sucker with a lot of reserve and more than most IMO. How old is your battery? How many volts does it have with ignition off, how many with engine running, how many after listening to radio for 1/2 hour? How many amps does your system draw?

I would think your problem is either charging related, or it's just an old/weak battery...

deekster_caddy wrote:

You must have a kickin system, or else a bad battery. I can run my system all day and still have enough juice to start it up.

Are you running a stock battery? Their CCA is very high compared to most. It's a big sucker with a lot of reserve and more than most IMO. How old is your battery? How many volts does it have with ignition off, how many with engine running, how many after listening to radio for 1/2 hour? How many amps does your system draw?

I would think your problem is either charging related, or it's just an old/weak battery...

Not sure about the amperage draw from the system. I just replaced the stock battery with a Duralast Gold made by thompson controls about 5 months ago. The CCA is 850 and the reserve power I believe is 1000. I do not have a voltage gauge and I fried my meter. The audio system is designed to shut off when the voltage goes below 10.6 volts. Of course by then it's too low to start it anyway. Never had it go into shutdown mode though.

The wattage rating is 360RMS for the four channel amp, and 1200RMS for the sub amp. Not that big of a system IMHO.

I think what happened is I did drain it once and I never put it on a battery charger to fully charge it and I know the alternator will not fully charge a battery but just keep it topped off at the current level. I'd like to avoid this situation in the future by having two fully charged batteries that remain charged even after running the stereo for a long period of time or at least enough to have to crank.

I also have aftermarket fogs that draw 5 amps when on (enough to cause the lights to significantly dim when at idle). I run a radar detector and police scanner constantly too (shhh), along with my digital HUD that remains on. I know I have a lot of constant draw, which is another reason for wanting a second battery.

Optima Yellow Top is a good choice for your purpose. You will want to run the second battery in parallel, NOT series. Use quality, thick ga power wire and beefy connectors; I would use an inline fuse on each positive battery terminal.

There will be an extra load on the alternator if both batteries are drained low, it's just part of the laws of physics.

AA wrote:

Optima Yellow Top is a good choice for your purpose. You will want to run the second battery in parallel, NOT series. Use quality, thick ga power wire and beefy connectors; I would use an inline fuse on each positive battery terminal.

There will be an extra load on the alternator if both batteries are drained low, it's just part of the laws of physics.

Think the alternator can handle it? I'm going to use 0 gauge amp power cable from knukonceptz for the cable run.

I think the alternator can handle it, at least for a while. Like most things, of you put extra load on it, the lifespan shortens. It will depend on how much & how often you discharge the batteries. If you let both batteries go completely dead, I'd remove the + terminal from the extra battery until the original one is fully charged, then reconnect. This is not convenient, but it works. Or, just try it for a while and if the alternator fails, replace with high-output version.

Another thing you can do is use a plug in charger when the batts are very low on charge. This will not put as much strain on the alternator when you start up the car.

Probably the best solution is to build or purchase a battery isolator, such as this:

http://www.powerstream.com/battery-isolator.htm

Make sure you read up on how it works and the proper wiring for your situation. I think you would wire the stereo amps strictly off the Yellow Top, and keep the stock battery for starting the car and other vehicle accessories. Might be the best way to go.

AA wrote:

I think the alternator can handle it, at least for a while. Like most things, of you put extra load on it, the lifespan shortens. It will depend on how much & how often you discharge the batteries. If you let both batteries go completely dead, I'd remove the + terminal from the extra battery until the original one is fully charged, then reconnect. This is not convenient, but it works. Or, just try it for a while and if the alternator fails, replace with high-output version.

Another thing you can do is use a plug in charger when the batts are very low on charge. This will not put as much strain on the alternator when you start up the car.

Probably the best solution is to build or purchase a battery isolator, such as this:

http://www.powerstream.com/battery-isolator.htm

Make sure you read up on how it works and the proper wiring for your situation. I think you would wire the stereo amps strictly off the Yellow Top, and keep the stock battery for starting the car and other vehicle accessories. Might be the best way to go.

Wow that's perfect and exactly what I want and need. I'm gonna have to look into that farther. Thanks AA.

the altenator may handel it but it will not charge them bouth full also the altenators 'shoes'(not sure how they are actualy called in english, just transelated the word what whe use in est for it) will wear out much faster.

Snowdog wrote:

the altenators 'shoes'(not sure how they are actualy called in english, just transelated the word what whe use in est for it) will wear out much faster.

We call them 'brushes'.

I think the alternator would eventually charge them both full, but it will take longer, and with added wear to the alternator.

I had my factory battery in my Bonneville along with an Optima Yellowtop in the trunk. I just had the guy run a positive cable to the Optima from the factory, and ground it out in the trunk. Dont quote me on the exact way to do it, but it worked great!

GMFreak8 wrote:

Think the alternator can handle it? I'm going to use 0 gauge amp power cable from knukonceptz for the cable run.

Unless you enjoy spending too much money for cables, just get 0 gauge cable from a Tractor Supply store or something equivalent. You'll be doing the same thing for half the money.

Rickw wrote:

GMFreak8 wrote:

Think the alternator can handle it? I'm going to use 0 gauge amp power cable from knukonceptz for the cable run.

Unless you enjoy spending too much money for cables, just get 0 gauge cable from a Tractor Supply store or something equivalent. You'll be doing the same thing for half the money.

Never thought of going there. I wasn't even aware they carry cables like that.

The better quality power cables I've purchased in the stereo shops offer some advantages over cheaper ones:

• Finer strands, much more flexible for easier install
• Jackets last longer and will not crack
• Clear insulation allows easier inspection
• Looks much nicer for installation

For such a short run, I use the good stuff. But the cheap one will technically deliver 12V just the same.

GMFreak8 wrote:

Rickw wrote:

GMFreak8 wrote:

Think the alternator can handle it? I'm going to use 0 gauge amp power cable from knukonceptz for the cable run.

Unless you enjoy spending too much money for cables, just get 0 gauge cable from a Tractor Supply store or something equivalent. You'll be doing the same thing for half the money.

Never thought of going there. I wasn't even aware they carry cables like that.

Your making a Battery to Battery run, basically.
So why not use Battery cable. Yes the stuff made for Amplifier installs is prettier but unless your going for show, I'd use Battery cable.
I ran regular battery cable from my underhood mounted battery to the rear of the cab of an extended pick up for amplifier install and ran it outside along the frame and up into the cab, through a sealed grommet for easier install. Did not reduce the efficiency of the Amps at all and provided a much more durable cable for a lot less money for that particular installation.
If what your running is very visible in the trunk and you are concerned with looks then get the "Made for Stereo" stuff. The more wire strands per diameter of cable doesn't hold water for Battery to Amplifier hook ups.
If your talking speakers and the need to be sensitive to impedance then from what I've read the more strands per Mil makes a difference.
But that is in the Lab and not on our cars.
I do agree with putting in-line fuses to protect your equipment between the two. Be it the Alternator, Amps or Battery's themselves.
And the Solid State battery isolator unit that AA referred you to for running multiple Batteries should be just what you need along with the Yellow Top which if i remember correctly is made for more Deep Cycle use. Just what you are wanting to do.