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CanoMod . A Main Hobbies . Boca Bearings

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Thunder Tiger Raptors 30-90 - Imperio > Electric Raptor @ Sandown
 
 
lozza6
Veteran
Location: Sydney, Australia

yeah, unfortunately 1KG for a battery is probably too much isnt it?

how much do 10S lipos weigh? I'm sure its not that much...

I hope they can make a lighter one... i think they should enter the hobby market, give hte lipos a run for their money, 500 for a battery is too much, and it why i'm still running nitro... would love to run this electric raptor though!

is the bird based on the titan? ie, not the now older V2.... for boom length canopy mount etc etc?

i love the V2, just lacking the longer boom adn metal head.
05-22-2006 Over year old.
 
 
Ben-T-Spindle
Elite Veteran
Location: Central Illinois

Everyone with the Raptor conversions run 10s1p, 11s1p, or 12s1p eMoli battery pack. A 10s2p eMoli pack as way too big and you really don’t need it anyway. The new CC Phoenix ESC’s go to 12s and that’s what most are using.

Hopefully there will be other low cost power tool cells out soon that have other capacities for more flexibility.

.

... BTS
05-22-2006 Over year old.
 
 
FlightPower
Veteran
Location: Herts UK

Top end lipos optimised for electric flight are running at 2900 Wh/Kg vs 1500 Wh/Kg for the lithium ion can cells optimised for the power tools. 1500 Wh/Kg will certainly get something up and flying but it's not the same thing that has been driving the excitement in electric flight. Don't forget that NiMH can cells have been at 20C -30C for ages. I just weighed a modern 6Cell 3800mAh NiMH pack (for a 10th scale RC Car) I have here (432g without wires). At the 20C spec this would give it 1231.48 Wh/Kg (assuming 7V under load) and 1847.22 Wh/Kg at 30C (assuming 7V under load).

At 1500 Wh/Kg, the lithium can cells at 15C are somewhere in the middle of these NiMH specs with respect to power:weight. Not sure it's worth the effort of dismantling a lithium powertool pack to end up with little or no advantage over older and even cheaper battery technologies.

Julian
05-22-2006 Over year old.
 
 
w.pasman
Elite Veteran
Location: Netherlands

Quote 
Energy Density 285Wh/l
Power Density 1500W/kg at 20 seconds


Wow that's a high energy density, are you sure that's right?
My LiPo pack is 38x34x54mm or 0.07l which is pretty small for a 2800pack at 8V, which it gives me 10.7Wh. That is about 150Wh per liter. This pack claims twice that??

But power density seems a bit useless. It says you need a pack of 1kg to get 1500W for 20 seconds. That means kilo battery to lift up a 60 size heli? And then you have to land after 20 seconds?

For all details on my pack see here
lipo pack
05-22-2006 Over year old.
HOMEPAGE  
 
 
w.pasman
Elite Veteran
Location: Netherlands

Quote 
Top end lipos optimised for electric flight are running at 2900 Wh/Kg vs 1500 Wh/Kg for the lithium ion can cells optimised for the power tools.


I doubt this even more. The pack I just mentioned weighs 119.2grams. That makes 89.8Wh/kg. 2900Wh/kg that is 32 times better. I may not have the latest greatest but this seems BS.
05-22-2006 Over year old.
HOMEPAGE  
 
 
w.pasman
Elite Veteran
Location: Netherlands

Quote 
At 1500 Wh/Kg, the lithium can cells at 15C are somewhere in the middle of these NiMH specs with respect to power:weight


Sorry but Wh/kg refers to capacity:weight, not to power:weight.
05-22-2006 Over year old.
HOMEPAGE  
 
 
FlightPower
Veteran
Location: Herts UK

You may wish to edit that to save red face later.

Julian
05-22-2006 Over year old.
 
 
GScott
Key Veteran
Location: Lewis Center, OH

No offense but since you work for a lipo manufacturer I will tend more to believe those that are actually using these cells and posting videos with realtime data overlayed.
05-22-2006 Over year old.
 
 
lozza6
Veteran
Location: Sydney, Australia

Thanks for that FlightPower,

I understand he works for a battery company, but what he says does make sense,

the capacity of lipos per gram is much better than the emoli cells...

people are sacrificing weight for money...

personally i fly nitros and i simply cant move across to electric yet, not with the prices of lipos, especially 10-12s packs.....

I'm hoping there will be more technological developments soon, to get the prices down,

emolis are definately a step in the right direction, higer amp draw ions... next we need them to drop the weight!!

Anyawy cant wait till i go electric, its all governed on the prices...

Loz
05-23-2006 Over year old.
 
 
w.pasman
Elite Veteran
Location: Netherlands

FlightPower,

Quote 
You may wish to edit that to save red face later.


LOL I thought it were you who should have a red face by now.
Check for instance this website for a definition of watt-hour (Wh)




Wh definition

Quote 
The watt-hour (symbolized Wh) is a unit of energy equivalent to one watt (1 W) of power expended for one hour (1 h) of time. The watt-hour is not a standard unit in any formal system, but it is commonly used in electrical applications.

An energy expenditure of 1 Wh represents 3600 joules (3.600 x 103 J).


Joules is an amount of energy. That is, capacity. Power is in Joules per second, also called Watts or "W" (notice the missing "h" ).
05-23-2006 Over year old.
HOMEPAGE  
 
 
ozace
Key Veteran
Location: melbourne, australia

I have a raptor 50 and a E titan. I choose to run V28 cells knowing full well they dont have the power or light weight of the latest greatest lipos. I also choose to run a TT 50 with 15% fuel. I dont need the blistering performance that is possible. Its all down to personal preferance and skill. I cant take advantage of a hyper on 30% so i dont run one. I do however use FP packs in some smaller helis and they have been and are still the best i have come across.

we can never have too many, can we ?
05-23-2006 Over year old.
 
 
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Modefo's RC Helicopters . XHELI.COM . Autography FlightPower

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Thunder Tiger Raptors 30-90 - Imperio > Electric Raptor @ Sandown
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