How much current can be drawn from a 1.5V AA alkaline battery? How much current can be drawn from a 1.2V AA NiMH battery?
2007-12-15 10:40:59 · 8 answers · asked by electric 3 in Science & Mathematics ➔ Engineering
In addition to voltage, batteries have another rating that represents their capacity -- milliAmp-hour or mAh.
A brand name alkaline AA battery has between 1700 and 3000 mAh.
Read the link below for more details.
There are some limits on the current draw due to the internal resistance of the battery.
2007-12-15 15:20:21 · answer #1 · answered by Thomas C 6 · 2⤊ 4⤋
All of the answers are correct, but you have to look at the size of the load on the battery and time you need it to operate.
If looking strictly at how much power you can draw, even if just for a short amount of time... a Thevenin equivilant circuit is your best bet to measure the output available. In Thevein you match your load to your source, then measure your load to determine the source's capability.
Connect the battery to a variable load (resistance) like a large potentiometer or decade box of resistors. Put your volt meter across the load and increase the load until the voltage reads one half of the battery voltage. Disconnect the circuit. Measure the resistance of the load, and apply ohms law. Since half the voltage is in the load/half in the source you have the same impedence, and as such, the same power.
Volts divided by Ohms = Current. That will give you the theoretical best output you can ever get from that battery. How long it will last depends on the size of the battery (and can only be found using a stop watch).
2007-12-15 11:58:03 · answer #2 · answered by Ken Mc 3 · 2⤊ 0⤋
1.5V AA alkaline: about 0.5A, any more than that and you get serious voltage slump.
1.2V NiMH: You can suck a lot of current out of these (see mag85), but I wouldn't go over 2 amps.
2007-12-15 14:24:15 · answer #3 · answered by quicksilv3rflash 3 · 5⤊ 0⤋
It does of course all depend upon the discharge rate, but nominal ratings for AA Alkaline batteries list capacity at 2850 mAmp-Hours. AA NiMH battery ratings are about 1700 - 1800 mAmp-Hours, perhaps.
For high discharge currents, the capacity would be less.
Astrobuf
2007-12-15 10:53:01 · answer #4 · answered by astrobuf 7 · 0⤊ 3⤋
enable R ohms be the resistance of each bulb while warm (chilly state resistance may be decrease) and enable V volts be the emf of the battery. Then blended resistance of the three bulbs is R/3. So V/(R/3) = 6 or 3V/R = 6 or V/R = 2 while one bulb is fused (open, not closed) the blended resistance is R/2. So modern = V/(R/2) = 2V/R = 4. modern drawn would be 4 A.
2016-12-11 05:58:07 · answer #5 · answered by ? 4 · 0⤊ 1⤋
"Ask the machine" - it never lies. If you want to know how long a battery can output under a heavy load, load it and time it. You may find that you can draw over an amp from a AA for over an hour, or even 10 amps for a few minutes. The best way to find out is to ask the machine.
Besides, your question is too vague - for how long a time? If it's a load that drains it gradually over perhaps 100 hours, you'll probably get close to the amp-hr rating. You'll get somewhat proportionally less for heavier loads.
2007-12-15 11:39:52 · answer #6 · answered by Gary H 6 · 0⤊ 3⤋
Normal design current specs for non-rechargeable batteries are about 0.1 amp from AAA, 0.25 amp from AA, 0.5 amp from C or D. A 9-volt battery is good for about 0.05 amps. NiMH can probably supply more, but for a shorter period of time.
2007-12-15 10:52:40 · answer #7 · answered by Anonymous · 6⤊ 1⤋
To answer this question you need to be more specific. Are you asking for the miliamp-hour or how many amps you can safely continuously pull without voltage drop or battery overheating.
2014-07-12 15:52:48 · answer #8 · answered by Anonymous · 0⤊ 1⤋