Tablet battery: reported full charge capacity more than design capacity, poor battery life

alipmcg

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Apr 16, 2014
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Hi, I have a Teclast X98 Air 3G tablet (it's a Chinese brand that I decided to take a chance on), I've had it since August last year, and since October last year the battery life has been pretty poor. Battery life was very good for the first two months, then something seemed to happen and the battery life dropped from about 8 hours to about 3-4.

The battery will charge to 100% and take a couple of hours to deplete to around 65%, then it drops very quickly to about 15%, after which it will generally last a couple more hours, usually lingering for a long time around the 10% mark.

HW Monitor reports the designed capacity as 14440mWh, and the full charge capacity as 31160mWh. Does anyone know why this could be, or what I could do about it?

I think the battery pack in this model is actually made up of 2 batteries, which I suspect may be playing a part in this. Any advice greatly appreciated, thanks in advance
 
Solution
As far as know all these battery % readers just monitor the battery voltage to guess a percentage left but lithium batteries have a very consistent voltage through the whole discharge and then a very rapid fall at the end. This makes these % readings completely guess work based on a perfect battery.

What you describe about reduced life in a short space of time sounds like a typical cheap battery. Higher quality ones have a far greater life. There is no way the battery is 31160 mha, it would be bigger than any laptop battery so no idea what it's reading to get that. Even 14440mha sounds a little on the high side.
As far as know all these battery % readers just monitor the battery voltage to guess a percentage left but lithium batteries have a very consistent voltage through the whole discharge and then a very rapid fall at the end. This makes these % readings completely guess work based on a perfect battery.

What you describe about reduced life in a short space of time sounds like a typical cheap battery. Higher quality ones have a far greater life. There is no way the battery is 31160 mha, it would be bigger than any laptop battery so no idea what it's reading to get that. Even 14440mha sounds a little on the high side.
 
Solution