Nice post on refurbishing your battery. I have looked into this issue extensively and decided it was too risky for me so hats off to you. As it is, Li-Ion batteries must be protected from being punctured and exposed to air. They run the risk of exploding. Also, Li-Ion his a finite # of recharge cycles before it becomes slightly unstable and risk of explosion while charging increases. The manufactures have to put in the chip as a matter of safety; granted there is a large margin of safety to protect the consumer and Li-Ion batteries are safe to use. However, I am sure some if not most of you have hard of cell phone batteries becoming excessively hot and in rare instances exploding. These shorting batteries are what needs to be prevented by the chips. The switch kills the charge function after about 400 charge-discharge cycles. That is complete 100-0% battery discharge. It keeps track of partial discharge as well so you don't just get 400 times changing the battery since you might only use 20-50% between charges. So bottom line, this is a safety function and not a stick-it-to-the-consumer trick. Some people have tried burning out the logic chip on the circuit board that controls the charging and have reported varied success. If you venture down your own experimental road and open these batteries, be very careful. The last thing you wand is a Li-Ion battery blowing up in your face.
By the way, I here 4 extended butteries that have gone belly up on me. If anyone is interested in experimenting, just PM me. You pay shipping and the batteries are yours.
Current: TX2525nr, iPad (yes, even the iPad).
Former: Motion Computing LE1700, 1400 and 1300, TC1100, P1510