The Stovebolt Site Forums The Shop Area The Electrical Bay I charged a 6v battery at 12v

I charged a 6v battery at 12v by accident overnight. Nothing happened, the battery didn't explode or crack. It felt a little warm to the touch but not hot. So far so good, the battery has plenty of power.

I did it many times when I was young and didn’t know any better. We would take the caps off and watch the electrolyte bubble. When it bubbled for a minute or so, we would disconnect the leads let it cool a minute or two and start over. Never did an overnight unsupervised charge. I’m surprised it didn’t boil dry or explode on you.

My brother blew up a battery by connecting it backwards. He was a teenager then so It was 50+ years ago. I think modern battery chargers have a lot of safety features built in to avoid accidents.

I've jumped a 6v battery with a 12v car, but not overnight!

you can jump a 6 volt battery with a 12 volt car? I didn't think that would work without frying the rest of the 6 volt electrical system.

If your lights/radio/etc are off, you can jumpstart a 6v vehicle with a 12v battery.

As soon as it starts, disconnect the a 12v lead.

My preference is not to do this - but, I have done it.

I'm not going to say I ever did this, nor will I say I've seen anybody do this. But, sometimes, just sometimes, you need to kick over that modern diesel, with its multiple computers, electronics and sensors, at 24v. 'Cause sometimes 12v just won't do it. Just sayin'!

This might explain it, the charger is only a couple years old and it wasn't cheap.

I don't really like boosting at 12 v either, but it doesn't seem to bother my dad at all. He seems to think it's no problem. Just like Tim, I pull the lead off as soon as possible.

It almost could have been another Chernobyl! I hope you're not planning on anymore kids!

To reinforce what Martin said. Check your electrolyte. Make sure you didn't boil the battery dry.

Justhorsenround, you make me laugh.........Isn't it amazing we are alive with no major scares and missing limbs. My in series double six volt system is only attached to my 45 amp 6 v generator and 6 volt starter. Due to me being a timing and 100% fine tune up, my old 54 starts immediately on 12 volt. It has been that way for 8 years and no problem but if it doesn't start right away I don't keep on. I attribute this to a manual choke. Ahh, to be young again and stupid, now I'm old and stupid, some things never change. Ed

Apparently industry standard these days has circuit sensing appurtenance that will determine battery voltage in the charger itself. It eliminates human error,lol.

This is the one I'm running these days, best one I've ever owned even has a 85amp starter assist. 6V/12V



https://www.oreillyauto.com/detail/...pickup-rwd?q=battery+chargers&pos=10

With a good battery, either 6 or 12 volt, the charging system is supposed to work hard for a few minutes right after startup, then cut back to a smaller current flow to maintain the charge. What most people who don't make a living doing auto electrical work don't realize is that the charging system powers the ignition, lights, wipers, heater/AC fan, and other accessories first, and then uses its remaining amperage capacity to recharge the drain on the battery from getting started. If you've got 50 amps' worth of constant demand, with a HEI ignition, a big thumpin' sound system, dual electric cooling fans, a big air conditioner blower, power windows, and an automatic electric buttwipe, the alternator must be matched to the constant demand, plus about 25% amperage over that number to keep the battery charged.
Jerry