Is it safe to use 2200 amh 11.1 watt battery with 18 amp Esc?

That depends on the motor you are using. If your motor draws more than 18 amps then it will fry your esc..also check if your esc can handle 11.1 volts. If your motor draws less than 18 amps the i guess its ok.

It would be better if you mention your complete power system and rtf weight of the model. Then people can answer your questions more appropriately.

Regards

I have emax 2822 motor and 18 amp esc and weight of plane is about 600 gram

If you have a bulb and it doesn't matters if you connect it to a 500 Watt UPS or a power from 5000 Mega Watt Nuclear  Plant!! Thats was for you Lipo ! Just kidding.

EMAX CF-2822 and its clones have a rating of 2S-3S Lipos and can take between 8-18AMP, depending on actual Cellcount, size of the Prop and max Throttle set(EPA). 

The rule of thumb is that you use ESC which is 1.5 times current rating of the motor. So you would be safe to use 30AMP or, at least a 25AMP ESC to live on the bleeding edge.

Surprisingly your 1st statement is wrong!! Usually people ignore it, and 90% time it doesnt matter but you need to see the C rating of the battery. It gives the maximum current you can draw from the battery by the formula (C rating)*(Ah rating).

Not mentioning what motor/Prop one gonna use , the question gives the feeling that the question is if battery would be over kill for an 18 AMP ESC, thus my analogy.

Excuse me ujjwaana as I am new in this field, this was in my mind  (i calculate only battery watt*c rating/1000 that 2200*25/1000 = 55 that is too much for 18 amp) and that is why I asked the question and as a new bee it is my right to ask such foolish question, and you senior are path maker for us thanks for your help. Ok means battery amp is not big issue for esc , it depends on motor how much watt it eats from Esc (my english is not so good, so forgive me if you are unable to understand, I will try to get you understood in other words) ok I have Emax 2822 motor and 9050 gws prop. motor specification says it will take maximum 16 to 18 amp and I have got the motor as combo pack from RCD I intend to fly 600 gram plane with this stuff

Hi all ,
I have often got  queries on the other side as well  so I will explain  how we decide on a power system:

1) The Motor : Max amp  is the deciding factor
2) The ESC rating should be higher than the  Motors ability to draw
3) The battery  should be capable of  delivering  at least 50 % more than the motor can draw at MAX 

Eg  today I got a customer  insisting on  using  11.1V 850 mah 20 c battery  to power a 2212/06 motor  using a 30 amp ESC .

As per us this is a clear NO NO NO. 

Because   his weakest link in the Power system is the battery  at Best it can deliver only 17 amps  while the motor can draw  upto 25 amp .

The ESC  rating is OK , but should for some reason the auto  low voltage cut off not work on the ESC  the battery would fail in the best case and burn in the worst case  leading to loss of control on the plane .

ASTA's   query is the opposite of  this case :
Asta  : Your battery is capable of delivering 55 AMPS as rightly  calculated by you  but the system will only draw what it needs , it will not draw excess  just because the excess happens to be available .

So you can safely use  the battery with an 18 amp ESC if the 18 amp ESC is  what is sufficient for your motor.

Sai

2200 maH/20c= 2200ma for 1 hour
ie: 2.2 amps for 1 hour
4.4 amps for 0.5 hours
8.8 amps for 0.25 hours
22amps for 1 min.
 20C indicates 20X2.2 amps, which  it can give instantaneous on demand, with considerable low drop out voltage due to the low internal resistance.

I did not understand the no 55.

From my practical experience, i do not load a 2200 mah/20C battery more than 25 Amps.
ashta

Thanks Sai and others friends for your help, it is clear for me and for others begginer

Wats the difference between ESC,BEC & UBEC?

ESC= Electronic speed controller.
BEC= Battery Eliminator circuit
UBEC= Ultimate battery eliminator circuit.

1. ESC is two types Brushed and Brushless and is used to control the speed of the motors as the name suggests.

2. BEC is used to connect the receiver to the Lipo/ Nicad battery. The Lipo/Nicad battery can be from 7V to 22 Volts depending on the no of batteries used. Since the receivers can take a max of 5V, we need a eliminator circuit to derive this voltage from Battery voltage of 7-22V. this is the BEC. Normally this is a Linear regulator.

3. UBEC is same as Sl no2, but with Switching regulator.
ashta

Thanks ashta ji..