NiCd and charging problem...Was: Re: Zenith ?????

From: jpero_at_mail.cgo.wave.ca <(jpero_at_mail.cgo.wave.ca)>
Date: Wed Jul 30 13:35:31 1997

>
> On a side note, when I opened up the case and saw the battery, it was
> just starting to corrode and would have eventually ended up ruining the
> circuit board. So just a reminder to all that if you are going to store
> computers that have batteries in them, it would be a VERY good idea to
> remove the batteries. In this case, the battery was soldered onto the
> board and I just cut the wires and put the battery in a zip-lock bag to
> be kept with the unit. This way if I ever go to get the unit running
> again, I will know what the proper battery is. I probably wouldn't
> remove nicads though unless the unit was going to be stored for an
> unknown (long) period of time and I suspected the nicads were over about
> 5 years old.
Side note about my compaq LTE 386s/20 and seen the problems on old
motherboards that has them on board. Lithium seems to be better
luck...

I think these NiCd's hates to be in discharged state for long time,
my working LTE 386s/20's 3 yr old battery shorted in short order in 2
month storage after long active use periodically through 3 years.
Yeech. After rebuilding that battery with exact cells, worked in fast
charge just once, after that I can't get fast charge from it, now
requiring 3 days to fully charge the battery. The new battery unit
cost $160 cdn and I will not buy it unless I know the problem is with
that rebuilt battery pack's internal circuit board or the internal
power supply inside that notebook. The power supply brick is not it,
already tried another one.

This charging system is weird...the power brick is just that and has
one wire more like "hey!, powersupply crank up that current up!" for
fast charge mode. Internal power supply is just that: dc to dc
convertor with bit of hardware to sense current to battery while
charging. The charger is actually INSIDE the battery pack.

The intenal power supply uses one SCR, two switching regulators to
provide 5v with low current negative v on the side for notebook. The
Compaq is not very nice to users who needs bit of more info to assist
their repairs.. :(

Thanks!

Jason D.
Received on Wed Jul 30 1997 - 13:35:31 BST