Batteries

[zam70]

I didn't really know if it was a gel or not...just kinda took it for granted. My basic opinion of those (and other deep cycles) have to do with their ability to deliver current. They are very limited on the amout of current they can supply on immediate demand (how many total amps they can deliver instantly, like on a transient or starting a car) Site is down right now so I can't verify but, as I recall the optimas were between 70-80 amps. A regular old chepy lead acid can deliver 125 amps and Ive seen them as high as 225 amps.

If they're working for you, that's proof in its own, but in the systems I (used) to build, they couldn't keep up. SO, that's where I've developed my opinion...every day typical use they are probably just fine. I just don't trust them.

Never tried them in my regal, never gave it the chance...pulled that sucker ouy as soon as I got it home.

 

[87gnblackdemon]

BTW, you never sent me the basket area volume of your CV sub for me to calculate that box for you. As soon as you find out, let me know.



I thought I did, sorry about that. Well, I found a box already custom built for my subs. It was on ebay and no one put a bid on it, so I e-mailed the seller and got it for pretty cheap. It's better for me anyhow, I didn't and don't really have the time to build one myself. Anyhow, thanks for the help.

 

[GNandTTA]

Optima Yellow top batteries kick ass!!!!!! Best battery I ever bought. Being mounted in the lower front fender on the TTA it dosen't even get the benefit of the warmth of the motor to increase charging ability. But has always performed perfect.

First dual battery setup I had was using a Sears marine battery. At the time (late 80's) that was the thing to do. Between that and the isolator I had more problems than I care to mention. Next in the early 90's was a Streetwires Gelcel battery. Total piece of crap!! Didn't last more than a year. By this time I had it done the right way using a solenoid. Got the Yellow top in 96' and still have the same battery. Am still able to go to the woods and crank it up for a good 1 1/2 hours (or untill the tree cops come) and still start the car.

 

[zam70]

hmmmmmmm...maybe I should give the ole yellow top a chance.

 

[GNandTTA]

Zamm, don't worry about the discharge ability. Optima's are one of the lowest internal resistance batteries around. Lower internal resistance means ability to discharge and charge. Temperature and age also come into play here. The warmer the battery is the faster it will charge or discharge. The yellow top is designed to be run down to practically nothing and still take a full re-charge. I can attest to it's ability. I've run the thing down to under 10 volts. The HiFonics amps are usually steaming by then - but still putting out full wattage.

 

[PRSRIZD_V6]

If that's the case I need some advice...

Here's a question then. Do you really need the solenoid setup, what are the drawbacks to running 2 batteries in parallel? (other than the alternator working harder? If the solnoid connects the batteries with the ingnition on then they are going to burden the alt anyhow, right? I don't plan on sitting in my car very often without it running, but is that the only convenience that the solenoid gives you?

I was thinking of just moving my Yellow top to the trunk and putting a red top underhood. It was just going to be the yellow top in the trunk until I realized that I would need a buncha extra wiring to pass tech inspection AND i would need an external kill switch.

 

[zam70]

Re: If that's the case I need some advice...

Originally posted by PRSRIZD_V6
Do you really need the solenoid setup, what are the drawbacks to running 2 batteries in parallel? (other than the alternator working harder? If the solnoid connects the batteries with the ingnition on then they are going to burden the alt anyhow, right? I don't plan on sitting in my car very often without it running, but is that the only convenience that the solenoid gives you?

I was thinking of just moving my Yellow top to the trunk and putting a red top underhood. It was just going to be the yellow top in the trunk until I realized that I would need a buncha extra wiring to pass tech inspection AND i would need an external kill switch.

You don't need the solenoid setup UNLESS you want to be able to isolate them from one another when the engine is off

If you run 2 batteries, they need to be the same type, age and size. THIS IS VERY IMPORTANT.

Why do you want 2 batteries...basically, if the rest of the electrical system is up to the task, 2 batteries are useless.

 

[PRSRIZD_V6]

I guess I would want to isolate certain aspects of the system I guess. I could cut off the fuel pumps with yet another switch. Which is nice. Originally I wanted just one battery in the trunk, but I'm not putting an ugly battery switch on the outside of my car to pass tech at a race track. So I thought it would be an easy out to just run 2 batteries.

Why do the batteries need to be the same?

Shouldn't 2 voltage sources in parallel be the average of the two? It's been a while since I had circuits, but it doesn't seem that important to me. Same internal resistance I guess I can see, but anything more seems kinda iffy. Maybe there's something I'm missing

Just wondering.

 

[zam70]

You want the batteries to have the same characteristics...internal resistance, charge/discharge rate, capacity etc...

 

[PRSRIZD_V6]

Got that, but is that just to say they are?? I mean yes performance will be better, but is it really that big of a deal?

 

[zam70]

The main problem is the rate of charge/discharge....lets say ther is a demand for power, if one battery is in good condition and one not, one battery will take the brunt of the work...same thing on charging...if one battery will take/hold a charge better the "bad" battery will have a tendency to draw off the good one. Personally, I'd just stick with one battery.

 

[PRSRIZD_V6]

Yeah, I can see that. It's kinda the path of least resistance theory since one battery more adaquetly supplies the 'juice'. Thanks for the clarification.

 

[GNandTTA]

The main problem is the rate of charge/discharge....lets say ther is a demand for power, if one battery is in good condition and one not, one battery will take the brunt of the work...same thing on charging...if one battery will take/hold a charge better the "bad" battery will have a tendency to draw off the good one.

This is generally only true if the batteries are connected together with the engine off. With the engine running the alternator raises the voltage level above the batteries so basically the alternator is dumping most or all of it's energy into the depleated battery.

I would only do the dual battery setup if you want to play the system with the car not running. There is no advantage aside from that.