Well as with any other hw hack, the crucial part is background

check what voltage it's supposed to have, what capacity (Ah or mAh)
find cells that fit and are of same capacity

then gently open the pack, take GREAT care in soldering the stuff loose
normally there is a temp fuse in there, you'll need to lead off the heat
with a metal clamp or something

do make notes and draw pictures of how it looks and is connected internally

stick with industrial cells WITH solder ears, soldering on a Ni-Mh or Ni-Cd
cell just ain't worth the effort, it can be done, just..ummm take my word
for it, it's easier with soldering ears

nimh has 1.2 volts per cell, so an industrial "cell pair" has 2.4 volts
2 pairs serial connected makes 4.8 volts (what my omnibook needs)
so 2 pairs, 4.8 volts, how about capacity(ampere)? well standard cells (original batterypack)
states 1600 mAh, the cells i have give 1800 mAh giving me a lil more time

when soldering the components together:

i won't take responsibility for your mistakes or clumsiness
i've done it, i know it can be done, but i won't be responsible
you do it all on your risk

anyway...
to close up the cells i'd stay away from glue or heat glue
use heatshrink tube for battery packs (model shops sometimes have these for
racing model (radio controlled battery packs))

make sure you don't shrink it "too fast" and let it cool
the reason to use tube instead of glue?
well battery pack might need another restoring in a year or so?
imagine using superglue...you'll spend hours prying it open if you can get it
open at all!!!
now..heat shrink (make sure you don't cover ventilation and assembly holes)
a sharp scalpel and 2 minutes and it's open
do make sure it's the heatshrink without glue in it (some heat shrink tubes
have heat glue on inside)

DO be clever and make sure you shrink the heatshrink tube carefully
remember that tube usually shrinks at right about the same temperature that is
unhealthy for the cells and battery pack.

wlofie
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