Makita made some of the best very small cordless drills, very handy, very compact. Don't throw those drills away for the want of a battery or plug in transformer type charger, they are great for small jobs around the house. The solder in & the two lead wire 7.2V battery types are up for bids on eBay I also have the harder to find 4.8V batteries in both types & the chargers for the same models.
Split the case, and buy some new batteries, and make a new pack. Cheaper. Easy. Put it back together with J B Weld.
The models I'm referring to have the batteries installed in the handles of the drills & require none of those drastic tactics......for less than $20 it wouldn't be worth the time or effort doing what you say even if it was possible.
Jon~
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