You have to know how to get into Recovery mode. You can do this with Quickboot when the phone is on, or the powered off phone method:
1. Power off phone or pull battery and replace.
2. Hold all three of these buttons down: Vol-Down, Camera button (lower left as you look at the phone) and Power on button).
3. You will see a small graphical menu come up. Most of us are using Clockwork, so I will focus on that - it will be a green menu.
For the battery wipe, Go to Advanced, navigate the menu with the vol up/down keys, and select using the camera button.
There are three ways so far:
The Drain Way:
1. Drain it down until fully dead.
2. Charge normally to full.
3. Reboot to Clockwork recovery and wipe battery stats (under advanced, on second page), reboot phone.
4. Turn everything on, flashlight, Bluetooth, Wi-Fi, Pandora, the whole nine, to quickly drain it completely dead.
5. Charge normally to full.
The Powered Off Charge way:
1. Charge your phone 100% while itís on
2. Unplug it from the charger, power off, then charge it up to 100% with it in a powered off state.
3. Unplug charger from phone. Power it on, and then charge it to 100% while the phone is on.
4. Unplug the charger and then reboot into Clockwork, go to advanced and clear the battery stats.
5. Power on, charge to full, and then enjoy.
Third option (thanks squshy 7), I paraphrased it and wrote it out a bit for ease.
Maybe we can call it the Mr. Miagi Charge way....aka Power On, Power Off, Charge On, Charge Off way lol
(the parentheses are the state of the phone)
1. Start with the phone powered on.
2. (Phone on) Charge battery until the LED turns blue
3. (Phone on) Unplug the phone from the charger, wait until the LED turns off
4. Power off the phone.
5. (Phone off) Plug the adapter into the phone, charge it up until the LED turns blue
6. (Phone off) Unplug, wait until the LED turns off
7. Power the phone on.
8. Wait until the phone is booted back up all the way, and then power it off again
9. (Phone off) Plug the adapter into the phone, charge it up until the LED turns blue.
10. Boot the phone into recovery mode
11. Go to Advanced, and then choose Wipe Battery Stats.
12. Power the phone on and use normally.