I am going to order batteries for my V911.
While hunting for them, I came across this:
http://www.hobbyking.com/hobbyking/store/__19419__Turnigy_nano_tech_160mah_1S_25_40C_Lipo_Pack_Fits_Align_Trex_100_.html

The stock batteries are 120 or 130 mah.
So I want to ensure whether or not the 160 mah one would work well and wouldn't damage the heli.

And how can I know if it fits in my heli?

Thanks!

The best you can do is make a thermacol piece as per the 160mah battery size from HK site and try to see of fixes into your heli.....  also note the battery weight of 160mah add that much more to the existing 130mah battery and try flying your heli... if all goes well then go ahead and buy 160mah with 100% surety of success.

all the best !!!

Thanks for the nice ideas!
I saw in the comments that it worked in the FP100 helicopters, and FP100 is the same as V911.
So now I am going to buy it.

btw I am absolutely new to international shopping.
Can someone be so kind to buy it for me and send it to me?
(Ofcourse I'll pay him the amount, its just the "online buying" thing...)

Even I use v911 and thought of increasing the battery but the cg of this heli will change
So you need to think in that respect also.

This means a slight imbalance and could lead to compromise on this beauty

Just checked... The weight of both (stock and Turnigy Nano-tech) batteries is 4g.

Which one will be better:

Turnigy 160mAh 1S 30C
http://www.hobbyking.com/hobbyking/store/__10980__Turnigy_160mAh_1S_30C_Eflite_Minium_compatible_.html

Turnigy nano-tech 160mah 1S 25~40C
http://www.hobbyking.com/hobbyking/store/__11893__Turnigy_nano_tech_160mah_1S_25_40C_Lipo_Pack_Kyosho_E_flite_Nano_CP_X_Parkzone_Etc_.html

nano tech .....