8.4 or 9.6 li-po
02-19-2004, 01:40 PM
#1
Member
Thread Starter
Join Date: Nov 2002
Location: beirut,
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
8.4 or 9.6 li-po
hi,
well if i have a brushless motor that works on 8.4 or 9.6 volts,can i find lithium polymers for it?
cauz all i can find 7.4 v or 11.1 volts
any ideas?
thanks,
well if i have a brushless motor that works on 8.4 or 9.6 volts,can i find lithium polymers for it?
cauz all i can find 7.4 v or 11.1 volts
any ideas?
thanks,
02-19-2004, 03:04 PM
#2
My Feedback: (21)
Join Date: Jul 2002
Location: Spencerport, NY
Posts: 7,350
Likes: 0
Received 0 Likes
on
0 Posts
RE: 8.4 or 9.6 li-po
Lithium cells are 3.7 Volts per cell. Sorry, no way to get exactly 8.4 or 9.6 Volts. Not that it matters.
In reality, a 7.4 Volt Lithium pack is equivalent to an 8.4 Volt NiMH pack. All packs suffer from "voltage depression" under load, where the voltage is lowered by the load put on the battery. Properly sized, a 7.4V LiPoly pack won't suffer nearly as much voltage depression as an 8.4 Volt NiMH pack. Under load, an 8.4V NiMH pack will read around 7 Volts. Under load, a 7.4V LiPoly pack will also read about 7 Volts.
You can also go to an 11.1V LiPoly, and run a smaller prop or a higher gear ratio to keep the Amps down. In most cases, it's the excessive Amps that kill the motor.
In reality, a 7.4 Volt Lithium pack is equivalent to an 8.4 Volt NiMH pack. All packs suffer from "voltage depression" under load, where the voltage is lowered by the load put on the battery. Properly sized, a 7.4V LiPoly pack won't suffer nearly as much voltage depression as an 8.4 Volt NiMH pack. Under load, an 8.4V NiMH pack will read around 7 Volts. Under load, a 7.4V LiPoly pack will also read about 7 Volts.
You can also go to an 11.1V LiPoly, and run a smaller prop or a higher gear ratio to keep the Amps down. In most cases, it's the excessive Amps that kill the motor.
