I don't really know where to post this question but I have a helicopter that had 3.7 volt 1500 mah lith ion batterys that went bad so I replaced them with the same only with 3000 mah the problem is it won't lift off so my question is that is there a discharge rate difference between the 2 different mah batterys. Does the 1500 deliver more amps then the 3000. I know the 3000 mah would give more lasting time but the discharge rate I don't know.

Weight difference?

Weight difference?

Have to ask the same question, weight?

Well I understand that there are also high drain batterys that are for helocopters. The ratings seem to go by 1 c up to10 c for high drain so maybe my batterys are not rated to put out the highest amperage, high drain plus the weight possibly.

There is another forum on the web that can answer those kinds of questions better. RC Groups.
https://www.rcgroups.com/forums/index.php

There is another forum on the web that can answer those kinds of questions better. RC Groups.
https://www.rcgroups.com/forums/index.php

Specifically, their 'Batteries and Chargers' and 'Electric Helis' subforums would probably be the best bet.