Re: z50 battery oddity

[Pavel Machek <pavel%ucw.cz@localhost>]

Hi!

> > What I don't know, however, is whether the charge control circuit is in the 
> > battery itself or if >it's in the z50. In any case, the long and the short 
> > of it is that yes, you can replace the Li-ion >cells, but the cells aren't 
> > readily available to consumers (I have seen them online and in >surplus 
> > stores), and you run the risk of causing a toxic metal fire if you screw 
> > things up :P
> 
> Each battery module has to keep track of its own cells' degradation
> over time (if you treat old cells like new ones, you'll severely
> overcharge them, which would be *bad* for Li-ion), so there's some
> intelligence built into the pack.

That's not how it works... most of the time anyway.

li-ion is constant current, then constant voltage (4.2V). You can't
overcharge, unless you provide wrong voltage (if you do, they explode;
both new and old).

Confused smart battery controller is bad, but if z50 has only 'high,
low, critical' battery states (does it?), it is probably not smart
battery.
                                                        Pavel
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