Laptop battery mah/mwh

fiigaro

Distinguished
Oct 26, 2010
2
0
18,510
So i just bought new laptop battery from
http://www.ebay.com/itm/7800mah-Batterie-Pour-ASUS-A72-A72D-A72J-K72-K72D-K72F-K72J-K72Q-A32-K72-A32-N71-/191218654883?pt=LH_DefaultDomain_71&hash=item2c85851ea3

It arrived few days ago. On battery it says 7800 mah
On ebay title it says 7800 mAh, on describtion 7200 mah.
After a few calibrations
Viso_ekrano_u_fiksavimas_2015_08_31_120218.jpg


Which means
https://milliamps-watts.appspot.com
* 10.8 v

6560277.777777777 mAh

Question. Did i get fooled or i just dont know how to calculate mah to mwh?
 

sizzling

Distinguished
Your problem is the 10.8v assumption. 10.8v is the voltage when near flat, it will be higher through most of its discharge cycle

That software is also making assumptions, the only way to accurately measure mha is to fully charge and then discharge the battery in a controlled manner.
 

fiigaro

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Oct 26, 2010
2
0
18,510
I did that once. Fully charged then left for 2 hours. Then used laptop until it went to hibernation. (pc do that then theres only 5% left in battery). Then after ~2 and a half hour i charged it for about 3-4 hours.