The charging circuitry in the phone should protect the battery from over discharge. It also protects the phone from overcharging. However, just like a spring, it's the constant charge/discharge that damages a battery. I would not run it down every...
Please actually read what I've posted...the directions may seem the same as what you've tried before but there are slight differences in some of them that may make them work for you.
1) Pull the battery, sim card, and sd card.