OK, Timbo, the posibilitys there, but isnt it true that lipo manufactures always insist on useing there own charger?, as a newbie i'm thinking that these batterys are put together diferent,not like a car battery ,all you need to know is it 12v or 6v , the only info, I, as a customer get is what it sayes on the package, I maybe mistaken on thinking that a charger thats made to charge a 800mAh cannot fully charge a 900mAh battery . of coarse to back up your point the 900mAh batterys shows charged in a shorter time than the 800mAh???,in the end all I wanted to do was to have longer flight times to learn to control this choper and this is supposed to be the easy one thanks Harry