From: Stuart Tedford <stuart.tedford_at_piresearch.co.uk>
Date: Fri, 20 Aug 2004 10:09:30 +0100

> -----Original Message-----
> From: Linus Nielsen Feltzing [mailto:linus_at_haxx.se]
>
> I don't have the complete picture of the problem, but the charging
> algorithm has a few safety measures that prevents it from
> charging, to protect the batteries:
>
> 1) It doesn't charge for longer than 450 minutes for 1500mAh
> batteries,
> so a weak charger may not be able to charge them in time.
>
> 2) It doesn't trickle charge for longer than 12 hours
>
> 3) It doesn't restart an interrupted charging cycle until
> after a grace
> period of 60 minutes, to let the batteries cool off.
>

4) Doesn't it also not start charging until a minute or so has passed when
first powered up (I think it's waiting for a valid voltage reading from the
battery) indicated by the ??? for battery level?

I think this is the main problem because when batteries are really flat,
they can't run for the full minute and so the unit shuts down before
charging starts. I remember Linus, you said the new boot loader fixes this
but how do you know what version bootloader you have?

Anyway, I think it wouldn't do any real harm to immediately start charging,
then after a minute or so, stop charging and wait for a reading from the
batteries. Someone else on the list said that the batteries become obsolete
so quickly these days that it really doesn't make sense to be overly nice to
them. I have been through 4 sets myself in 3 years on my V1R: original
1500mAh, 1650mAh, 1850mAh, and now 2300mAh. I don't think charging for 1
minute regardless of vBat is going to destroy batteries anyway. It could
even be done only in the bootloader when powered on by charger insertion.
Meaning that it only happens when people are explicitly trying to charge the
battery.

Stu.
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Received on 2004-08-20