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# 12V in a 24V Battery?

#1
04-07-04, 08:53 AM
endoment
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12V in a 24V Battery?

Will a 12V battery charger charge a 24V battery? Will it hurt it? Is 6amps too much for a 1.2amp requirment?

Charger = 12V & 6amps

24V Battery = 24V & 1.2 amps

#2
04-07-04, 09:09 AM
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Location: Central New York State
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Why would you even think of trying something like this?

Don't do it.

#3
04-07-04, 09:18 AM
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Why Not?

I didn't think it would hurt it putting less voltage in it.

#4
04-07-04, 10:24 AM
DANSKOTA
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If you compare electricity to water, voltage is like water pressure, and amperage is like water volume. To fill a swimming pool in an hour you can use a very large pipe under low pressure (low volt, high amp) or a smaller pipe under very high pressure (high volt, low amp), much like a KV transmission lines used by the power company.

In your example, the 24v battery has the equivalent of twice the water pressure-even at a low charge level. Your chager will most likey overload, burn, smell bad, and maybe even fire! The battery, if fully charged may explode from the rapid discharge-just like of you short out the terminals. This is the way I understand it.

You should buy a 24volt charger. A quick search found http://www.batterystuff.com/battery/24volt.htm

The amperage indicates the rate of charge. You asked if a 6 amp would be enough. This depends on the size of the battery (amp/hr). If it is a big battery, like a marine battery for your boat or RV, a 6 amp charger would take many days to completely charge the battery. If it is a small battery, such as what you'd find in a kids remote controlled toy, then 6amps would be too much. It just depends on what your charging.

Hope this helps!

One more thing. You typical 12 volt charger actually has more like 15volts output. This is to keep the "water" flowing in the right direction.

#5
04-07-04, 10:58 AM
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Location: welland ontario
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A 12 volt charger will not charge a 24 volt battery even if left on for a year.
A 12 volt battery is actually 13.5 volts. A 24 volt battery would be near 26 volts. In order to charge a battery you reverse the current flow though it. That requires a voltage higher than the voltage of the battery. The higher the voltage the more amps flowing and the quicker the charge. To much charge current and the battery will boil dry and be damaged.

Last edited by joed; 04-07-04 at 11:55 AM.
#6
04-07-04, 11:36 AM
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Join Date: Oct 2003
Location: Davenport, Iowa
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I don't think you would hurt your 12 volt charger by hooking it to a 24 volt battery (because of the diodes in the circuit) but you certainly won't charge the battery either. Better find a 24 volt battery charger if you wish to recharge a 24 volt battery.

#7
04-07-04, 02:28 PM
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NEW INFO... I opened it and there two battery's ! I think there both 12V... Just needs a 24V Power Supply to charge both I guess

#8
04-08-04, 01:25 PM
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Connecting 2 12V batteries in series will give you a 24V battery. Assuming that their ESR and leakage are identical (or close) you can place a 24V charger across them and they will each charge equaly. They will also discharge equaly. Think of all of the radios that take batteries and also allow you to connect a DC power supply. Most of them will take 4 batteries, but will require a 6 Vdc power supply. 4x1.5V/battery = 6V.

#9
04-08-04, 07:43 PM
scrapiron
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What type of batteries are we talking about here and what do they power?

#10
04-09-04, 06:46 AM
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If you have two 12 volt batteries, then just charge them individually before connecting them.
If you have one 24 volt battery that has a decent charge on it, then even if it doesn't ruin your 12 volt charger, the charger will not be able to over come the higher voltage of the battery and nothing will be accomplished anyway (except running the risk of overheating the charger from reverse flow).
If the 24 volt battery is completely discharged and you put the 12 volt charger across it, it will only charge to 12 volts anyway and still be useless.

#11
04-11-04, 10:24 AM
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How Should I wire this up? Each battery is a 12V...

#12
04-11-04, 11:32 AM
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Wire this up?? I must not understand because I see nothing to "wire up". Just connect your battery charger to one battery until it is charged, then connect it to the other.

#13
04-11-04, 12:51 PM
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Sorry I forgot to add... It needs a fuse and kill switch... For you woundering it for a scooter, the controller went dead. So I'm wanting to wire it so it runs all the time with out the speed controller.

Also the battery's are wanting to take a charge from what I can tell.

#14
04-14-04, 07:51 AM
scrapiron
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If you want to charge both 12v batteries at the same time with a 12v charger you must connect them parallel, that is all positive terminals together and all negative terminals together. To get your 24 volts for motor operation then you must change the batteries back to a series connection. It would probably be easier as suggested to just charge one at a time. I don't know anything about scooters but riding one without a speed control sounds like a real hoot.