What is battery life inaccurate?

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What is the phenomena called that gives inaccurate batter life
readings? For example, my battery goes almost to dead then I charge it
for 10 minutes. I put the battery back in my phone and it reads near
full. After a little while, the indicator starts adjusting and gives a
more accurate read.

I see this with every cell phone. Also with Windows Mobile devices
(Pocket PC). The phone and battery can be brand new and the same thing
will happen. Why does the battery life indicator have problems with
accuracy?

Thanks,
Brett

 

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Archived from groups: alt.cellular.sprintpcs (More info?)

brett wrote:
> What is the phenomena called that gives inaccurate batter life
> readings? For example, my battery goes almost to dead then I charge it
> for 10 minutes. I put the battery back in my phone and it reads near
> full. After a little while, the indicator starts adjusting and gives a
> more accurate read.
>
> I see this with every cell phone. Also with Windows Mobile devices
> (Pocket PC). The phone and battery can be brand new and the same thing
> will happen. Why does the battery life indicator have problems with
> accuracy?

Battery charging is basically causing a chemical reaction inside
the battery. Right after disconnecting the charger, the chemicals
are still in a state of agitation, and it takes a while before you can
get an accurate reading of the charge state.

--
John Richards

 

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Archived from groups: alt.cellular.sprintpcs (More info?)

In article <1123064022.805144.115360@g43g2000cwa.googlegroups.com>, "brett" <account@cygen.com> wrote:
>What is the phenomena called that gives inaccurate batter life
>readings? For example, my battery goes almost to dead then I charge it
>for 10 minutes. I put the battery back in my phone and it reads near
>full. After a little while, the indicator starts adjusting and gives a
>more accurate read.

Because at least most battery indicators are based on a linear
reading of voltage, but a battery's ability to deliver power is not
linearly related to voltage. Furthermore what you are observing are
changes in the battery's "internal resistance", and how it interacts
with the electrochemical cell voltages (half-cell potentials).