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Subject: Re: FM Recorder battery?
From: Maik Bühnemann (M.a.i.k_at_gmx.de)
Date: 2003-02-08


Hi!
This ist a part of an interesting article about how to manage li-ion
batteries:

    "Lithium ion batteries reach power densities of 230 Wh/l. As
electrolytes organic connections or salt melts serve. A combination of
lithium with aqueous electrolytes is not possible due to the reactivity of
the lithium. During the loading and discharge process ` ' the lithium
ions between the metallic oxide cathode and the anode on carbon basis
swing in electrolytes back and forth, why this system also lithium Swing is
called. The cell rated voltage of the system amounts to
depending upon structure 3.6 or 3.7 V and cannot replace usual designs
therefore so easily. Numerous recall actions shifted the call
of lithium systems early a heavy impact. Thus Notebooks burned out
proper, and Japanese Mobiltelefon Akkus got rid of with a flame impact of
its positive pressure. Improved cell structure and
sophisticated protection electronics led however in the meantime to a high
security of this system. This necessary protective circuit is also
the reason, why ` naked ' left ion cells for the final consumer are not
available.

    The optimal charge of the left-ion-Akkus is complicated and special Akku
Controllern reserved,

    which work usually in several phases: If the cell tension dropped under
2,5 V, they load one hour with 0,1 C over 2,5 V with constant
voltage and a maximum river by 1 C are loaded. The charging current drops
then within 1,5 to two hours slowly. If the charging current does not
sink any longer considerably, a timer starts. After one hour the
cell received then its full capacity. Which the offerers of devices with
lithium Akkus conceal gladly, the limited life span of left ion
chemistry is independent, of the done cycle number. A meaningful use of
left-ion-Akkus is limited because of the inevitable loss of capacity to
zirka three years."

My Question: ist the charging done by archos hardware or does the firmware
control this?

MAik

----- Original Message -----
From: "SeeSchloss" <SeeSchloss_at_zmail.pt>
To: <rockbox_at_cool.haxx.se>
Sent: Friday, February 07, 2003 9:51 PM
Subject: RE : FM Recorder battery?

> Hi,
>
> Hmm I dont think that the battery they put in the FM Recorder
> is very bad... Most of the time I have to recharge my unit
> after having used it for 12H...
> But if your charged your FM Recorder with Rockbox I think
> it may be damaged since Rockbox doesn't know how to manage a
> LiIon battery...
>
>
> SeeSchloß
>
>
>
> > So, when I first got my FM recorder, it got about 5
> > hours of continuous play off the battery before it
> > died. Now it only gets about 2-3 hours before it dies
> > (after a full charge from the charger it came with).
> >
> > The only thing is, I did install a daily build of
> > rockbox fm on jan 23 & jan 27 2003, but I have since
> > removed the ajbrec.ajz file (but not the .rockbox
> > dir). Is there any way that the rockbox could've
> > damaged my battery/unit? Or is this just a really
> > shoddy battery they put in it. It is now totally
> > useless for any long flights or day trips away from my
> > charger.
> >
> > The only other thing I will say is that I did buy a
> > Radio Shack 6-volt/1000 miliAmp car charger (which
> > works fine), but my battery problems started well
> > before I started using the car charger.
> >
> > Any comments on the subject at all will be
> > appreciated!!! Should I send my unit back to Archos?
> > Thanks a lot!!!
> >
> > Andrew
>
>



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