Syma S107G Battery Mod 350mAh 15 minutes flight time

Syma S107 Battery Mod 15 minutes of flight time using 350mAh Li-Poly battery. The charge time was 90 minutes using supplied USB cable and Logic3 dual USB charger. I also have another charger as a leftover after my knackered Salvation 1 helicopter which was charging this battery in 45 minutes. Didn’t test with Syma S107 yet. The actual model of this RC helicopter is Syma S107G. Information on the box states 3,5 channel helicopter. If only someone could tell me what that magical half of channe