Can this deep cycle battery be charged by an alternator?

[dwh]

Must depend on the battery... One time I had mine (Delco Voyager flooded) discharged somewhere down around 9-10 volts (yea I know that's bad, it was unintentional). When I first connected a 10-amp charger to it (older manual-style charger), it pulled so much current it caused the charger to go into overload and shut off (it's meter immediately pegged with a *clink* sound for about 15 seconds before the internal breaker cut out). I had to charge it through a headlamp bulb (used as a resistor) put in series with the charger's lead for about an hour before the battery had enough surface voltage to not kick the charger off when connected straight to it.

Just an observation I made with mine.

I do that all the time.

My truck has an antique Shauer 10a charger hardwired into the aux 12v bus and connected to shore power. I buy cheap batteries and abuse the crap out of them.

And yea, when I run the battery way down and then fire up the generator the charger will overload and kick the internal breaker. But after a while the breaker resets and it tries again. This will happen a dozen times or so (trickling a bit of power into the battery each time) and then it'll finally turn on and stay on.

But I don't think it's overloading from a huge current draw. I think it's overloading from a huge resistance. Once the battery finally gets a bit of a charge in it and the breaker stays on, the amp draw usually reads an amp or less on the meter. After a couple hours it'll generally climb up to 6 or 8 amps and then after 12 hours or so it will have tapered back off to around an amp.

 

[4x4junkie]

Funny, mine's a Shauer too (wonder if we have the same one lol)

I never observed mine taper off and go back up again though. After i reconnected the charger directly, the meter still was close to pegged (meaning lots of current draw), and after a moment it then drifted down to around 6-7A, and stayed there for the better part of a day. Finally it started dropping down to around 2A and I removed the charger at that point.

 

[dwh]

Funny, mine's a Shauer too (wonder if we have the same one lol)

I never observed mine taper off and go back up again though. After i reconnected the charger directly, the meter still was close to pegged (meaning lots of current draw), and after a moment it then drifted down to around 6-7A, and stayed there for the better part of a day. Finally it started dropping down to around 2A and I removed the charger at that point.

Yea, not surprising. Like I said - it depends.

It could just be different batteries, but most likely is that I'm draining my battery further. There've been times I've run the battery dead, but it still has enough juice to run the LED lights. Then, I've dozed off with the lights still on (oops). Next morning, the battery was so low it could barely light up the LEDs. That's happened more often than I would care to admit.

At times, I've seen the battery as low as 9v or even a little less. I regularly hit below 10v.