I have been flying with 7.4V 2000mA Lithium Polymer from Kokam. They are as good as NiCad with only 1/3rd the weight. I can get easy 6 flights per charge and will continue to test up to 8-10 flights. I believe that FMA is selling these batteries in the USA. If you don't know where to get them, email us and we can supply.

Lithium Polymer is good for our J600 if you need to save the weight. Note that Li Polymer is not the same as Li-Ion.

B777