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what makes a RC LiPo discharge rate (C) is different ? Answered

Exmple : 7.2v 800mAh 15C, 11.1 2200mAh 20C

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AndyGadget

8 years ago

 
The difference in 'C' rating is due to tweaks to the chemistry and construction of the cell and is the maximum continuous current you can pull from the cell and not have bad things happen.  Manufacturers are obviously trying to aim for higher 'C' and as always, the highest spec cells cost more, but depending on your application a lower 'C' value may be perfectly adequate.

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RendydevaraAndyGadget

Answer 8 years ago

thanks for your reply.

is there any way to increase the discharge rate ?

i have test a current of short circuit of my single cell LiPo (800mAh) is about 11A.
and 2P (two cell paralel (800mAh and 1100mAh)) is more than 12A.

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AndyGadgetRendydevara

Answer 8 years ago

 
Short circuiting LIPOs is a VERY bad idea and can result in explosion and burnout, like in the video I linked.  LIPOs do not like to be mistreated.
If you got 11A from one cell of the 3S1P you mention above then that's about right : 800mA * 15 = 12A.   (The resistance of the wire and the 'health' of the cell will be significant in the maximum you can pull from it.) 

Is this for an RC plane, as you mention in the tags?  If so, which motor are you planning to use with it?  Do you actually need 12A from the battery. 
If you draw 12A from that then you'll drain the 800mAH batt in less than 4 minutes!  If you're planning pulling a continuous high cureent then LIPOs may not be the ideal choice.

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AndyGadgetRendydevara

Answer 8 years ago

 
You'd be fine with that battery and motor combo unless you're running at WOT all the time although I'd be tempted to use a larger battery to increase the flight time, but as always with building a plane it's a tradeoff between power, weight, handling and time in the air.  There's a fairly low KV on that motor - Is it for a slow aerobatic model?

I've just received the depron to make a small version of one of THESE using the leftovers from a PZ Sukhoi I recently trashed - Never could get to grips with those ailerons.  I built a nutball a while ago and also have a very tame PZ cub.

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RendydevaraAndyGadget

Answer 8 years ago

maybe yes, but it can handle 10x4.7 prop.
is there any tricky to make an RC Plane ?

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AndyGadgetRendydevara

Answer 8 years ago

 
If you've not made one before, a nutball is a great one to start with - It was my first build - And great fun to fly.  You could use that prop / motor combo for thhat.  See the link above for the build thread.  Look for the YouTube videos, but search for 'rc nutball' otherwise you find videos of people throwing heavy objects at each others testicles.

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steveastroukAndyGadget

Answer 8 years ago

What the OP seems to be showing is a HIGHER discharge rate has a HIGHER capacity. I haven't seen that before.

Steve

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steveastroukAndyGadget

Answer 8 years ago

Ah ! So he's comparing two DIFFERENT batteries !

That makes more sense !

Thanks

Steve

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steveastrouk

8 years ago

What figures are your quoting there ?

Capacity is a complex phenomenon of the chemistry and construction of the battery, and is affected by the discharge rate and charge rate, really, because unless you want to under stand a lot, it just is.

Steve