I've done a bit of rebuilding myself. What I've done is to make sure that I
solder to the tab left over after I've cut it free from the bad cell. This
keeps the heat down on the cell itself. I also use a good hot iron and work
quickly, first tinning the tab and then letting the battery get back to
normal before soldering the two batteries together.

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Why isn't there an Ozone Hole at the NORTH Pole?