[WikiReader] Battery Life

[Jeff]

I just burned through the 2nd set of batteries with my wikireader in a 
month and a half. I know I have averaged less than 15 minutes a day of 
on time, so I am getting no where near the 90 hours of battery life 
advertised. Don't know if I have a bad one, or if the code needs tweaking.

Anyone else notice the battery life has not been so good?

Jeff

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Re: [WikiReader] Battery Life

[Alex Teiche]

On Fri, Dec 11, 2009 at 4:08 PM, Jeff  wrote:

> I just burned through the 2nd set of batteries with my wikireader in a
> month and a half. I know I have averaged less than 15 minutes a day of
> on time, so I am getting no where near the 90 hours of battery life
> advertised. Don't know if I have a bad one, or if the code needs tweaking.
>
> Anyone else notice the battery life has not been so good?
>
> Jeff
>

I don't have a WikiReader, but are you using Alkaline or Lithium batteries?
The voltage of Alkali based batteries will decrease over time, so that often
they will not be able to power an electronic device even though they are not
fully discharged.  Lithium batteries are best for things like the WikiReader
because the voltage stays constant for the most part.
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Re: [WikiReader] Battery Life

[Jeff]

Alkaline, the original energizer batteries that came with the device. I 
may have some NiMH batteries lying around somewhere, but I don't have 
any AAA lithium polymer nor a suitable charger.

Alex Teiche wrote:
>
>
> On Fri, Dec 11, 2009 at 4:08 PM, Jeff  > wrote:
>
> I just burned through the 2nd set of batteries with my wikireader in a
> month and a half. I know I have averaged less than 15 minutes a day of
> on time, so I am getting no where near the 90 hours of battery life
> advertised. Don't know if I have a bad one, or if the code needs
> tweaking.
>
> Anyone else notice the battery life has not been so good?
>
> Jeff
>
>
> I don't have a WikiReader, but are you using Alkaline or Lithium 
> batteries?  The voltage of Alkali based batteries will decrease over 
> time, so that often they will not be able to power an electronic 
> device even though they are not fully discharged.  Lithium batteries 
> are best for things like the WikiReader because the voltage stays 
> constant for the most part.

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Re: [WikiReader] Battery Life

[David Garabana Barro]

O Sábado, 12 de Decembro de 2009, Jeff escribiu:
> Alkaline, the original energizer batteries that came with the device. I
> may have some NiMH batteries lying around somewhere, but I don't have
> any AAA lithium polymer nor a suitable charger.

NiMH will be even worse.
They autodischarge 5-10% on first day, and 1% every next day...

-- 
David Garabana Barro
jabber & google talk ID:da...@garabana.com
Clave pública PGP/GPG:  http://davide.garabana.com/pgp.html


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Re: [WikiReader] Battery Life

[Al Johnson]

On Saturday 12 December 2009, David Garabana Barro wrote:
> O Sábado, 12 de Decembro de 2009, Jeff escribiu:
> > Alkaline, the original energizer batteries that came with the device. I
> > may have some NiMH batteries lying around somewhere, but I don't have
> > any AAA lithium polymer nor a suitable charger.
> 
> NiMH will be even worse.
> They autodischarge 5-10% on first day, and 1% every next day...

That depends on the NiMH. Several manufacturers are now making them with very 
low self discharge (~5%/month). They work very well in applications where I 
previously stuck to alkalines, such as my Psion 5 which probably has a lot in 
common with the wikireader.

I would also suggest trying a different brand of alkalines. The discharge 
voltage characteristic varies significantly between brands, and some devices 
stop working with the battery at a relatively high voltage. The Psion often 
works well with alkalines that other devices claim are dead. Even when the 
Psion has finished with them, they can be recharged with a suitable charger.

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Re: [WikiReader] Battery Life

[Glenn]

At 17:50 + 13/12/09, Al Johnson wrote:
>On Saturday 12 December 2009, David Garabana Barro wrote:
>>  O Sábado, 12 de Decembro de 2009, Jeff escribiu:
>>  > Alkaline, the original energizer batteries that came with the device. I
>>  > may have some NiMH batteries lying around somewhere, but I don't have
>>  > any AAA lithium polymer nor a suitable charger.
>>
>>  NiMH will be even worse.
>>  They autodischarge 5-10% on first day, and 1% every next day...
>
>That depends on the NiMH. Several manufacturers are now making them with very
>low self discharge (~5%/month). They work very well in applications where I
>previously stuck to alkalines, such as my Psion 5 which probably has a lot in
>common with the wikireader.
>
>I would also suggest trying a different brand of alkalines. The discharge
>voltage characteristic varies significantly between brands, and some devices
>stop working with the battery at a relatively high voltage. The Psion often
>works well with alkalines that other devices claim are dead. Even when the
>Psion has finished with them, they can be recharged with a suitable charger.
...

Hey!

It is these batteries:
http://en.wikipedia.org/wiki/Low_self-discharge_NiMH_battery

Glenn

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Re: [WikiReader] Battery Life

[Glenn]

At 20:36 +0100 13/12/09, Glenn wrote:
>At 17:50 + 13/12/09, Al Johnson wrote:
>>On Saturday 12 December 2009, David Garabana Barro wrote:
>>>  O Sábado, 12 de Decembro de 2009, Jeff escribiu:
>>>  > Alkaline, the original energizer batteries that came with the device. I
>>>  > may have some NiMH batteries lying around somewhere, but I don't have
>>>  > any AAA lithium polymer nor a suitable charger.
>>>
>>>  NiMH will be even worse.
>>>  They autodischarge 5-10% on first day, and 1% every next day...
>>
>>That depends on the NiMH. Several manufacturers are now making them with very
>>low self discharge (~5%/month). They work very well in applications where I
>>previously stuck to alkalines, such as my Psion 5 which probably has a lot in
>>common with the wikireader.
>>
>>I would also suggest trying a different brand of alkalines. The discharge
>>voltage characteristic varies significantly between brands, and some devices
>>stop working with the battery at a relatively high voltage. The Psion often
>>works well with alkalines that other devices claim are dead. Even when the
>>Psion has finished with them, they can be recharged with a suitable charger.
>...
>
>Hey!
>
>It is these batteries:
>http://en.wikipedia.org/wiki/Low_self-discharge_NiMH_battery
>
>Glenn

Here you have an older version with a list of battery names:

http://en.wikipedia.org/w/index.php?title=Low_self-discharge_NiMH_battery&oldid=180982680

Glenn



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