One other thing to mention is the 1c charge rating ( how many amps ) will change if you change the capacity of the battery. So if you have a 4500mah battery 1c=4.5 amps as an example. The c rating on the battery (50c, 60c, etc) has to do with the discharge current of the pack. The bigger the c rating, the more punch the pack should have...but c ratings on packs are a whole different story.