Hi Matt

We started to the field with two sets of batteries charged one set of 5000's and one set of 6400's. After the first flight the 5000's came out of the model at no more than 105F. We put the 5000's on the charger and started them while we flew the second packs this time 6400 were in the plane. We flew the 6400 for about 4 to 4 and half minutes landed and took them out they were also around the same temps. The first packs took about 30 minutes to charge and put back about 2200 to 2500 mah. After the first recharge on the 6400 they took about the same. The longest charge time we had was after the fourth flight started flying the batteries a little harder and took about 40 minutes to charge and put back about 3400 mah.