charging an 8 volt battery

Is it possible to charge an 8 volt battery with a 12 volt battery charger

Yes it is. I set my charger on 2 amps. Charge them slow. RB

I have a variable transformer and an old school manual battery charge. By varying input voltage to charger I vary the charging voltage and changing rate.

George

I always used a 6 volt charger on them,, 12 volts will boil them

(quoted from post at 16:35:17 12/31/19) Is it possible to charge an 8 volt battery with a 12 volt battery charger

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9.2V for full charge and 9.5V for an equalizer charge or use in freezing weather .

I had one in my old chevy grain truck for 35 years,, I only put two 8 volts in it in all those years,, must have worked,, but what do i know lol

I just use the 6 volt setting, been working for 30 years or so. Long slow charge is best. joe

The charger I have now does not have settings for 6 or 12 volts. You just hook it up and it knows. I emailed the company and asked if it would charge an 8 volt battery. They replied and said it would not.

I would not use the 12v setting.

Bring it up as far as the 6v setting will take it, then let the generator bring it up to full charge...

Provided the regulator has been set up for 8v. Otherwise it will simply operate as a partially charged 8v.

With a older non-smart charger, put 2 12 volt headlights in parallel with each other and feed the charging current through them into the battery. they will draw voltage and make nice with the 8volt. If it seems to be charging Ok put it on a timer so you can check it every hour or so. When disconnected it should be about 8.3 or 8.4 volts when charged. Jim

b & d,

At 2.1 volts per cell wouldn't an 8 volt battery (4 cells) have 8.4 volts at full charge?

Obviously YES a 12 Volt charger "can charge" an 8 volt battery. I've done it successfully over years as a farmer and used tractor dealer on a ton of tractors and never had a problem. Of course, if the charger has like low medium and high settings USE THE LOW !!!!!!!!!!!!!

If you only have 6 Volt charger use it on the Medium to High setting. If its a high current high capacity 12 volt charger you have to use it sparingly not very long.

WARNING HOWEVER subject to its design and limitations and rating a 12 Volt Charger COULD OVERCHARGE an 8 Volt battery !!!!

You should NOT just turn it on and let it run continuous. You have to monitor and watch for excessive outgassing and boil over and use it for a limited time.

In the past if I used a 6/12 charger I started with the 6 volt ON HIGH charging and if needed and there want excess outgassing and over boiling I could if needed use the 12 on LOW to top it off.

Using a Hydrometer and Voltmeter can help insure proper charging and avoidance of overcharging.

BOTTOM LINE while YES a 12 Volt charger can charge an 8 volt battery USE CAUTION and on lower settings and don't overcharge...

If you use a 6 Volt Charger try it on the medium to high settings and monitor the battery (hydrometer and Volt Meter once at rest and stabilized) and subject to battery condition it can provide a degree of charge BUT IT MAY NEVER ACHIEVE A DEEP FULL CHARGE like a more accurate more expensive smarter charger could that was specifically designed to charge 8 volt batteries

If you use a 12 BE CAREFUL and lower settings and monitor water levels and outgassing.

John T