I got one with a used UL I bought, and eventually disassembled it in
frustration- It has 7 volts of cells, with circuitry to up the output to 12v,
and also (I assume) to manage charging current &c. I recently purchased two of
the battery packs for $19/ea from JEM, and have succeeded in getting it to
charge at about 150ma, using a current-limited 25v supply, but the charging is
cut off (I assume by the circuit inside the battery) in only a short while,
and the longest I've been able to run the laptop from battery is about 20
minutes.
I don't have an NEC factory AC power-supply/charger, so I don't really know
what the circuits are expecting...
So- please, if anyone knows how to charge these things, or has a factory power
supply that seems to be successfully charging them, please post a reply here?
joel jaycock@keck.hawaii.edu
Keck Observatory
Mauna Kea, Hawaii