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Subject: Re: [JB6000] Charging Bigger Battery than before
From: Michael O'Quinn (michael_at_oquinn.info)
Date: 2003-10-04


I think I see what you are getting at. I'll answer each point, where it
makes sens to to so.

On Sat, 4 Oct 2003, Sir Pandolphe - IncrediMail wrote:

> Hello,
>
> Thank you for your answer.
>
> I have already read all of yours FAQ.
>
> Your Battery FAQ says that :
> Does Rockbox charge the batteries more/less/worse/better than the Archos
> firmware?
> ------------------------------------
> Player: Rockbox doesn't affect the charging on Players, it is all done by
> hardware logic out of software control.
>
> Ok, I Have understand this.
>
>
> I Will try to speak step by step.
> If you don't understand, you can say what you dont understand.
>
> 1*> ) Normally, they are 1500 mah NIMH Battery on the Player.
> 2*> ) The Archos Player 6000 charge the Original 1500 mah Battery with ONE
> cycle of charging. I Connect to 220V my archos and i'm waiting for the
> Battery Charged" message. Is it Ok ?

Yes.

>
>
> 3*> ) Now, I have put IN my Archos Jukebox 2300mAh NIMH Battery. Before,
> they are 1500 mAh Battery, now 2300 mAh battery on my Archos. Is it OK ?

Yes

> 4*> ) When I Connect to 220V my archos, it will display "Battery Charging...
> , and after, it will display "Battery Charged". But, I Have NOW 2300 mAh
> Battery on my player 6000 !

Yes. Nothing is wrong.

>
> 5*> ) I Think really that the archos don't charge fully (full) the 2300mAh
> Battery with ONE cycle of charging.

The batteries should be fully charged.

The player charges the battery until the voltage starts to drop. That
voltage drop means the battery is starting to get hot, even hotter than it
gets during normal charging. The reason it starts to heat up is that the
batteries are "full", and are not accepting any more charge.

So, (a) Battery is full, (b) as a result, it's temperature rises, (c)
because of that it's internal resistance rises, (d) which makes the
voltage drop slightly, (e) which is sensed by the charging control chip in
the player, (f) which shuts off the charging.

Some people claim that it takes several discharge/charge cycles for NEW
batteries to get up to full capacity. So it might be a good to just use
them for a week or so before trying to do any timing tests to check their
capacity.

> 6*> ) Before I have plugged on my Archos The 2300 mAh Battery, I have
> charged the 2300 mAh Battery with a specific charger.

That is fine. I lost my wall-wart (the external transformer, 110 volt in
my case) and always have to charge my batteries externally. I just have 2
sets and rotate them between the charger and my player.

>
> 7*> ) The archos has work during a very long time, but now, when i charge
> with my Player 6000 (battery on my archos) the autonomy (duration of
> playing) is more little than when i have used my 2300 mAh Battery charged
> with a specific charger...

Are you actually timing it? Or are you using the Battery Time Remaining
indicator on the screen?

Remember, you have to go to Menu -> General Settings -> System -. Battery
Capacity and change the number from 1500 to 2300. The will make the
display more accurate. Note that this setting does NOT affect the
charging cycle, it ONLY affects the "time remaining" display.

If you are using a clock to actually time how long the player plays using
various combinations of batteries and chargers, remember that the bitrate
and encoding method (VBR vs. CBR) of your mp3s can have a radical effect
on the battery play time. The higher the bitrate, the more often the hard
drive has to spin up to re-fill the memory buffer, and that results in
shorter play times before the batteries are exhausted. So, be sure to use
the same music each time for your comparisons.

It may be possible that an external charger charges the batteries a little
better or a little worse than the charging circuit built into the Player.
Only controlled testing with your specific hardware will tell for sure.
But I wouldn't expect more than about a 10 or 15 percent difference, if
you are using a decent charger.

>
>
> I Hope that you have understand me, i typped this email during 1h00 !
> I'm sorry for busy you.

I think I understood fine! Your English is a whole not better than my
French. I have a year of French from High School, but I'm afraid I would
be totally lost if I had to really rely on it...

I hope this helps. Good luck!

Michael



Page was last modified "Jan 10 2012" The Rockbox Crew
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