Re: z50 battery oddity

Pavel Machek <[email protected]> Tue, 1 Apr 2008 21:34:10 +0200
Newsgroups gmane.os.netbsd.ports.hpcmips
Message-ID <[email protected]>
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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