naturerecordists
[Top] [All Lists]

Re: Re: Ruined rechrageable? - RFI

Subject: Re: Re: Ruined rechrageable? - RFI
From: Syd Curtis <>
Date: Sat, 11 Oct 2003 22:46:25 +1000
My grateful thanks to Naturerecordists for the advice on actions I might try
to charge my over-flattened Tascam Nicad.  I am intrigued by Rich Peet's
suggestion -

> 
> Put a charge in reverse polarity.  If it explodes or goes to melt
> down you held it too long.  If it does not get very hot it is not
> enough.  

Tempting though it is to find out what happens, I'll observe his
instruction:

> This is a last ditch approach.  Do what anyone else
> recommends first.
> 

The Maha Energy instrument recommended by Rob Danielson sounds great, and I
shall make inquiries about obtaining it first -

> More of an investment, but Maha Energy makes a $90 smart analyzer
> charger reconditioner that I've been using for such restorations and
> fast charging custom nimh battery packs with a wide range of
> voltages, and single, odd nimh batteries I find for cheap that I
> don't have the right connectors for,.. Handles nicad tooi. Runs on on
> ac or 12volt in the field. The model I have is #MH-C777Plus-II. Rob D.
> -- 
>

I wonder if there is a model that runs on 240 V ac?  Anyway I can always use
the 12 V dc.

If I'm unable to find a supplier, then I'll be back to my proposal of trying
a burst from my 12 v car battery with Walter's excellent suggested
modification of reducing the current and voltage:

> 
> You should be able to get enough charge into it so the Tascam charger
> will recognize it. Some chargers refuse to deal with a full flat
> battery, but unless one of the cells was damaged in the full discharge
> it should charge.
> 
> I'd try and get closer to normal voltage for the battery to start the
> charge. You could use the discharge lamp in series with the battery pac
> to cut down the current and voltage from a car battery. Give it a few
> minutes and then try the Tascam charger again. Unless the pac has
> something in it that's dead it should pick up if fed long enough.
> 

Thanks again.

Syd Curtis in Brisbane, Australia.

________________________________________________

My original posting:

I fear I have just killed a Nicad rechargeable for a Tascam DA-P1 DAT
Recorder.  Put it on a discharge lamp prior to recharging for a field trip,
and forgot about it.  Completely flattened it, and the Tascam charger can't
charge it.

Before I consider pulling it apart for possible replacement of the cells,
does anyone know of any way that it might be shocked back into charging?

Its a 7.2 V battery.  What is likely to happen if I connected it to a 12 V
car battery for say one second?

Any advice gratefully received by this elderly incompetent.





________________________________________________________________________
________________________________________________________________________

<Prev in Thread] Current Thread [Next in Thread>
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the naturerecordists mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU