charging a large batt bank with little alt

[MrSkippyJ]

I know, but the thread says charging a bank...I didn't think we were talking about using a charger to keep them charged until he said that later on.

[Miguels]

Keeping batteries maintained, but if you constantly have a bank of dead batteries that the alt is the sole source of charging watch how long the alt lasts.

So what happens if you turn on your accessories, like headlights, ignition, AC, heat, amplifiers that draw +100A?

Where do those amps come from?

It will eventually kill the alternator. I keep telling people herelocally to upgrade alts. No one listens and they end up with dead alternator. If the alternator is big enough to maintain 13+ volts it will last longer. If it's constantly seeing below battery resting voltage it won't last long because it's getting overworked

[kirill007]

it still won't be a constant draw. The accessories might be but it won't be that much. The amps aren't likely drawing full current the whole time either. Amplifier draw is very dynamic which is much different than the static load that a bank of dead batteries would put on an alternator.

It wouldn't be smart to get the batteries dead in the first place. A battery draws less then 8A to charge it up if no load is attached. And that's with a really dead battery (below 9.5V).

10*8A=80A

Those 4 amps draw at least 1000A at full tilt.

Skippy is right

Skippy, you also have to see it this way. Nobody has the alt power to sustain the amount of amperage needed. Even with dynamic music. Dead batteries do kill an alternator quick but same happens if you play full tilt all day and don't have the alternator power to sustain 13.8v. You will always see people dip into the low 12's and keep it th at way. That puts strain on the alternator and kills batteries as it does and eventually kill the alternator. That's why charging batteries constantly is a must.

The alternator will keep on working as long as you don't overwork it, charging batteries is a relatively easy task compared to the amplifiers used.

[MrSkippyJ]

my assumption is that the batteries would be dead, but this was made before he clarified he would be using a charger on the batteries.

and besides, if a battery only uses 8 amps when charging, how do quick chargers work?

[Miguels]

I think they take up more amperage than 8a. That's why you see some batteries swell.

[kirill007]

my assumption is that the batteries would be dead, but this was made before he clarified he would be using a charger on the batteries.

and besides, if a battery only uses 8 amps when charging, how do quick chargers work?

Higher voltage charging= more current flowing through the battery.

That's why it's impossible to fully charge a battery at 12.8V, no potential difference=no charge.

Look at the A-meter on these battery chargers, you'll see it won't be very high. (although these batteries aren't "dead")

last 20s of this video, the rest is garbage. :https://www.youtube.com/watch?v=nXqIjjozzsM

last 20s of this video: https://www.youtube.com/watch?v=TdjHPUtUD9I

from 2.30 to 2.40: higher voltage= more current :https://www.youtube.com/watch?v=M8fcYVjCvQE

[MrSkippyJ]

So what keeps an alternator from doing the same as a quick charger? Won't a dead battery try to pull as much amperage as is available? Anyway, I'm only passing information that Mechman says to be honest. I may have twisted what he said a bit since it has been a while since I read it.

[im45pl]

Yeah sorry for the initial confusion, they will be charged after shows and maintained. Im just trying to get some thoughts on a good and preferably not so expensive option to keep decent voltage at shows

[poorfish88]

my assumption is that the batteries would be dead, but this was made before he clarified he would be using a charger on the batteries.

and besides, if a battery only uses 8 amps when charging, how do quick chargers work?

Higher voltage charging= more current flowing through the battery.

That's why it's impossible to fully charge a battery at 12.8V, no potential difference=no charge.

Look at the A-meter on these battery chargers, you'll see it won't be very high. (although these batteries aren't "dead")

last 20s of this video, the rest is garbage. :https://www.youtube.com/watch?v=nXqIjjozzsM

last 20s of this video: https://www.youtube.com/watch?v=TdjHPUtUD9I

from 2.30 to 2.40: higher voltage= more current :https://www.youtube.com/watch?v=M8fcYVjCvQE

That's great you watched a bunch of shit videos on how a battery charger charges a battery.

Now go watch videos on how a alt charges dead batteies. You'll notice it's output is a hell of

alot more than 8 amps.

[MrSkippyJ]

my assumption is that the batteries would be dead, but this was made before he clarified he would be using a charger on the batteries.

and besides, if a battery only uses 8 amps when charging, how do quick chargers work?

Higher voltage charging= more current flowing through the battery.

That's why it's impossible to fully charge a battery at 12.8V, no potential difference=no charge.

Look at the A-meter on these battery chargers, you'll see it won't be very high. (although these batteries aren't "dead")

last 20s of this video, the rest is garbage. :https://www.youtube.com/watch?v=nXqIjjozzsM

last 20s of this video: https://www.youtube.com/watch?v=TdjHPUtUD9I

from 2.30 to 2.40: higher voltage= more current :https://www.youtube.com/watch?v=M8fcYVjCvQE

I want to figure this out. I just assumed because of who it was coming from that it was true but I could have misunderstood. Now that I am really thinking about it, I think it might have been said that the batteries suffer the most when charging with an alternator when they are dead. Because it takes so long to charge them that they likely won't get a full charge on just alt alone...time to learn!!