I have the Bionic with the standard battery and an extended battery. What are my options for charging the batteries outside of the phone? I want to charge one while using the other. Specifically, is there a charger that will charge the extended battery when it is not in the phone? I saw that there is a "battery dock" that will charge the phone itself and another battery at the same time, but I didn't know if that would work with the extended battery outside of the phone? Any other options?