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Let´s say I have a 2 AA 1,5V 1000mAh Alkaline battery cells in series.

The circuit it´s connected to consumes 500mA, works at 3V and it´s powered on always, and taking into account other electrical specs as ideal, the time it would take to last would be:

1000mAh / 500mA = 2h

Is this correct?

I´ve checked this question and it confuses me.

LazyTurtle
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    Calculate the watt-hours (Wh). – Jeroen3 May 12 '20 at 12:28
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    Are you likely to get both in AA sizes? – Andy aka May 12 '20 at 12:35
  • Add the datasheet of the specific batteries concerned. As Andy is hinting, one is probably lying about its spec. To address the question : if both are honest about their capacity, and used according to their ratings, the answer would be No. –  May 12 '20 at 12:46
  • Two AA 1,5V 1000mAh Alkaline batteries connected in series Making that a 1,5 V + 1,5 V = 3 V battery. Connecting in series doesn't affect the current so it remains 1000 mAh. So basically you're asking if 1 liter of fuel lasts as long as two times halve a litre of the same fuel. – Bimpelrekkie May 12 '20 at 12:49
  • Thank you all for the comments. This is a theoretical question, not based in any datasheet. – LazyTurtle May 12 '20 at 12:50
  • @Bimpelrekkie You are right. I'm going to edit the question so that you can understand what I'm asking for – LazyTurtle May 12 '20 at 12:54
  • @Bimpelrekkie I´ve changed the question, hope it makes sense now. Thank you – LazyTurtle May 12 '20 at 13:14
  • 1000mAh / 500mA = 2h Ideally yes, however the voltage will change (rapidly) as the battery capacity decreases, making current consumption go up (if there is a regulator there demanding 3V). Even if you don't have a regulator, you won't be able to drain the battery all the way to 0, your actual runtime will be closer to 1 hour. Check this other question for details. – Ron Beyer May 12 '20 at 13:49
  • "mA-h" has units of charge. "Capacity" here is like "this amount of electrons are stored in this little cylindrical container". When you connect a path from its terminals, that many electrons flow before the voltage goes to zero. So the same # of electrons flow even if you have 2 cells in series. So the mA-h or A-h does not change no matter how many cells are in series. (What changes is the voltage those electrons "come out at, from the entire series", so to speak.) – Atomique May 12 '20 at 22:18

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