Battery smokin' hot

[Protagonist]

Originally Posted by Wazbro

Well someone in the campground I am at now had 1 battery go bad (reading 8 volts) and the other battery (still read 12.3 volts) got extremely hot and boiled out.

That's usually how it works when only one battery goes bad in a two-battery parallel setup. Because of the bad battery not taking a charge, the voltage regulator/charge controller never does shut off, and it overcharges the good battery until it cooks. Then you''ll have two bad batteries. And depending on how much acid leaked out and how much damage the acid did, maybe a battery box that needs replacing as well.

[Lumatic]

Originally Posted by Wazbro

Well someone in the campground I am at now had 1 battery go bad (reading 8 volts) and the other battery (still read 12.3 volts) got extremely hot and boiled out.

Also when boondocking if someone leaves the lights or something on and runs 1 battery down you would still have the other one.

Yeah, the first scenario is a possibility, but unlikely if batteries are installed in pairs.

If you will indulge my proclivity to play devils advocate with scenario #2. Running a battery way down reduces it's life. You are less likely to do so with both batteries on the circuit.

But this is really just bull. The real reason is I am a lazy an forgetful SOB who does not want to deal with remembering to flip a switch. Now if there was a gizmo that would think for you...............

[Protagonist]

Originally Posted by Lumatic

Now if there was a gizmo that would think for you...............

There is. It's called "Yes, dear!"

[ROBERT CROSS]

Two new batteries and get rid of the P-Lax battery burner.

A multi-stage converter works much better, especially if your plugged for long stretches.

Bob

[Jackcat2]

Thanks for the info, everyone. I' m going to wait till I get back to AZ to replace the batteries, can get them at cost. My remaining one is still good. Learned a lot. If my controller is bad I can get it replaced on my seen ice plan and will check into what's been suggested. Really dumb of me not to routinely check the water level, I know better but just put it off... and off. NO more, feel fortunate that I caught it in time. Phoenix: we will be in a resort near Phoenix next week for three months, interested in your solution.

[Drathaar]

Originally Posted by Jackcat2

Thanks for the info, everyone. I' m going to wait till I get back to AZ to replace the batteries, can get them at cost... stuff clipped...

Please ensure that you've disconnected ground from the battery that was smoked.

I just (today) bought batteries for my trailer. I originally was going to put Group 27s in, and bought them at Costco ($191 for the pair, including $18 core fee). When I got the old batteries out, there was a nice little tray in the bottom of the box that kept the Group 24s from moving around, so I went back and exchanged the Group 27s for the smaller Group 24s. The price for pair of Group 24s was $160 something.

I don't know what your cost is, but to me, the difference in price would be worth the peace of mind by picking up two new batteries and not worrying about the trip home. BTW, I am world class at worrying...

[Phoenix]

Lumatic,

The Airstream battery charging days are on a recurring schedule that pop up on my PC every month as a reminder:

* First Friday of the month = Turn switch from OFF to battery #1.

* Saturday = Change switch to battery #2.

* Sunday = Turn switch to OFF.

This schedule automatically repeats every month, and each battery gets charged for about 24 hours.

I change switch positions when I retrieve our mail from the mailbox, so this requires very little extra effort.

[LFC]

Originally Posted by Lumatic

I am trying but can't really think of an advantage to charging and using dual batteries one at a time opposed to 2 at a time. 1+1 still equals 2, and 100 amp hours and 100 amp hours still = 200. What am I missing?

There is no advantage that I can think of when using it in a trailer.

[ROBERT CROSS]

Originally Posted by LFC

There is no advantage that I can think of when using it in a trailer.

Well...you can isolate both batteries while plugged into SP, to avoid battery burning. As long as you have a converter that will provide power without batteries in the loop.

Bob