# Do 4 x 1.2V/1800mAh batteries in series = 1 x 4.8V/1800mAh battery?

**URL:** <https://boards.straightdope.com/t/do-4-x-1-2v-1800mah-batteries-in-series-1-x-4-8v-1800mah-battery/398002>\
**Category:** Factual Questions\
**Created:** [March 29, 2007, 5:12pm UTC](https://boards.straightdope.com/t/do-4-x-1-2v-1800mah-batteries-in-series-1-x-4-8v-1800mah-battery/398002 "2007-03-29T17:12:52Z")\
**Posts on this page:** 3\
**Page:** 2

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**Author:** ![Jeff\_Lichtman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jeff_lichtman/32/1531_2.png) [@Jeff\_Lichtman](https://boards.straightdope.com/u/Jeff_Lichtman)\
**Post date:** [March 30, 2007, 1:56am UTC](https://boards.straightdope.com/t/do-4-x-1-2v-1800mah-batteries-in-series-1-x-4-8v-1800mah-battery/398002/21 "2007-03-30T01:56:28Z")

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[QUOTE=groman]  
How do you figure?  
[/QUOTE]

Oops - my mistake. I was thinking of mWh, which is a unit of energy. The total stored energy is the same regardless of how the batteries are hooked together, but that’s not true for mAh.

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**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\
**Post date:** [March 30, 2007, 8:51am UTC](https://boards.straightdope.com/t/do-4-x-1-2v-1800mah-batteries-in-series-1-x-4-8v-1800mah-battery/398002/22 "2007-03-30T08:51:43Z")

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From experience with small electric model aircraft, I’d say NiMHs will have no difficulty putting out the current to run a laptop. A plane can run a set of NiMHs flat in under ten minutes without killing them (tho’ they may get good and hot at multi-amp current draw). And if you want to search around a bit, you should be able to get higher capacity AAs if you happen to want higher capacity - there are some about the place that are well into the 2200-2300 mAh range.

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**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\
**Post date:** [March 30, 2007, 11:41am UTC](https://boards.straightdope.com/t/do-4-x-1-2v-1800mah-batteries-in-series-1-x-4-8v-1800mah-battery/398002/23 "2007-03-30T11:41:20Z")

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[QUOTE=treis]  
Excuse me, mAh is stored current, not energy. Still, big difference between the two.  
[/QUOTE]  
And if you multiply the stored current by the voltage, you get [stored energy](http://boards.straightdope.com/sdmb/showpost.php?p=8381630&postcount=40).

Let’s say you had a battery with a stored current of 1 amp-second at 1 volt. 1 A·s = 1 J/s·V x 1 s = 1 J/V; 1 J/V x 1 V = 1 J. Therefore, it stores 1 joule of energy.

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