Olin Lathrop wrote:
>
> > Thanks for the info Olin, but I want to question
> > something in Panasonic's literature; even at 0.05C
> > the battery won't charge fully in 20 hours.
> > Averaging their current and time figures you get
> > 0.0415C for 15 hours. This is only 0.62C and allowing
> > for normal losses the battery is not even HALF charged!
> > You normally need to allow 30% to 40% overhead with
> > any rechargable battery...
>
> That's because I snipped that quote from a description of a complete
> charging algorithm which included charging at much higher rates for part of
> the time.


Fair enough. If you charge it at high C rates first
then permanent trickle charging afterward becomes
a different issue.

One more point, most of the "problem" they mention
with overcharging seems to be related to the
"excessive temperature rise" causing destructive
chemical changes in the battery.

At 0.1C and 1.4v at full charge you only have about
60mA into a AAA size battery, only 84mW will be
dissipated into a metal object of that mass will only
rise 2 or 3 degrees celcius. I can't believe that
will have any effect on the battery, and our real
world experience backs that up.
-Roman

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