Hi, I finally found and bought a battery charger which fits my needs. It is for double A batteries only along with some smaller types, but it is small, fitting in a briefcase and has a plug which folds into the unit when not in use. It can be taken along with the book port and other devices which use double A batteries. Hoping that someone who uses rechargeable batteries can tell me about their experiences, and what type of battery to buy, and maybe where. Radio shack is the first place that comes to mind, but wonder if there are online stores which might sell them. Also hoping someone could tell me how long the battery life is, assuming a full charge and using the batteries on the book port. Thanks in advance. Otto