Path: utzoo!attcan!uunet!wuarchive!usc!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!ark1!nems!dtoa3!goldberg
From: goldberg@dtoa3.dt.navy.mil (Goldberg)
Newsgroups: comp.sys.laptops
Subject: Re: Zenith supersport 286 battery
Message-ID: <2631@nems.dt.navy.mil>
Date: 18 Jul 90 13:00:46 GMT
References: <1990Jul17.131027.1976@vaxa.cc.uwa.oz.au>
Sender: news@nems.dt.navy.mil
Reply-To: goldberg@dtoa3.dt.navy.mil (Mark Goldberg)
Organization: David Taylor Research Center, Bethesda, MD
Lines: 29

In article <1990Jul17.131027.1976@vaxa.cc.uwa.oz.au> a_schwartz@vaxa.cc.uwa.oz.au writes:
>I am having difficulty in getting a full charge into the battery
>which comes with my Zenith Supersport 286(20 mb hard disc).  On
>three occasions in a row it has run out of juice after between 70
>and 80 minutes use as a dumb terminal hooked up to the Vax I am now
>on, which involves no hard disc use after initial connection.
>The 286 is one year old; the battery has been drained and recharged
>perhaps a dozen times. Previous to these incidents, it has lasted for
>more than three hours of word processing, with lots of disc activity.
>A program called "Battery Watch" version 1:00(C) has been installed on the
>hard disc. It has a "Deep Discharge" feature which they claim will
>"discharge the battery as deeply as possible"..."in order to remove
>a memory-effect problem in a NiCad battery."  I do not have the Battery
>Watch manual with me.  The 286 owner's manual does not tell you exactly
>how to recharge the battery.

I also have a Zenith laptop with the same battery, which is now dead.
I also took steps to discharge the battery and avoid memory effect.
(Memory effect is when the battery "thinks" it has less capacity due
to recharging when only partially discharged.)  So you could say my
battery now has amnesia!

Anyway, I suspect the problem I have weas probably due to overcharging,
which in turn was due to leaving the battery installed while unit was
plugged into AC.

Another possibility is lousy battery technology on the part of Zenith.
Anyway, if and when I replace the nicad cells, I'll try the measure
of disconnecting the battery when using AC.