I'm making a Quadrotor with following parts:
EMAX 4in1 ESC's (25A)
MWC Multiwii se V2.5
BLDC 980Kv motors.
FS-TH9X tx and 8ch RX.
For now i'm using a 9V general purpose battery. N I'm buying a 11.1V, 20C, 2200mAh LiPo
Now the problem that i'm getting is that when I use this battery, ESC's get calibrated but just to test the motors when I go up on the throttle, the motors do some rotations and then they stop responding at all.
The same goes for the FC, when I make the connections as per the conditions the FC keeps rebooting again and again. I tried to set my E.POINTS and SubTrims but then after a while the FC doesn't responds at all.
I made the quad of aluminium bars.
Can anybody suggest me a solution to this ?

these motors will not run without enough ampere so general purpose batteries will not work

if you are planning to buy lipo consider buying a 25C or greater with 2200, or buy 2800mAh or greater with 20C for your configuration.

Okay, I'll try and buy a Lipo 2800mAh 20C or better. I let ya know bout the progress.
Thanks for assisting

Quote from: akhilzid on January 29, 2015, 01:19:39 AM
these motors will not run without enough ampere so general purpose batteries will not work

if you are planning to buy lipo consider buying a 25C or greater with 2200, or buy 2800mAh or greater with 20C for your configuration.

OKay, so I searched a bit and I found this one: http://www.ebay.in/itm/Turnigy-3300mAh-3S-30C-Lipo-Pack-/191437166101?pt=IN_Toys_Games_School_Stuff&hash=item2c928b5615
Turnigy 11.1V, 3300mAh 30C (max 40C). So is it compatible with my configuration ?
My motors are 980Kv and 25A ESC's

Try Hobbysea.in you can get cheap deals on zippy batteries.
Also you can contact store owner of robu.in for cheap deals on Hobbyking batteries.

For your configuration you can safely use a 2200mAh 3S 30C or higher. But if you need more flight time, you can go for higher capacity batteries

Okay so i've been working my brains off, but still I find the concept of having a suitable battery along with the ESC combination n getting i right.
Can you jz brief me bout the C concept and how to choose battery for max. flight time ?
Also I intend to add FPV to that setup.
The config remains same.
Like I've finally built the quad. but due to lack of battery haven't seen it in action ...
I'm desperate to do it but not at the cost of harming it or compromising with the flight time.
Thank you.

While buying a battery(LiPo) you should consider these factors  ,

C rating :Peak continuous discharge capacity

mAh rating : Battery capacity (how much energy the battery can store)

Battery voltage : This depends upon cell configuration you can chose from single cell (4.2V) , 2S(8.4V) , 3S(12.6V) 4S(16.8V)....

Cell configuration : This is how the cells are arranged inside a battery pack a 3S pack means, 3 cells are connected in series , a 4S1P means 4 cells in series and one cell in parallel to this.

While selecting a battery for any purpose, you should mainly take care that, the battery is of required voltage, the battery can supply sufficient current .

In a multirotor, the total current draw is mainly by 4 rotors (Current draw by other electronics is negligible) . for your quadcopter , your motors runs at 3S and assume each motor's max. current draw is 15A (at full throttle) , so total current draw by motors can be up to 60A . So the battery you select for this quad should be able to contiguously supply more than 60A.

In a LiPo Peak discharge current = C rating x mAh rating  (Discharge rating x Battery capacity)

So for a 3S 2200mAh 30C LiPo, Max discharge current = 30C x 2200mAh = 66A - which is little above your requirement, and you can safely use this battery pack.

Key points to note, while purchasing LiPo :

1) Required battery voltage (For your quad, a 3S (12.6V) battery will do)
2) Max. discharge current should be higher than max. current draw by your setup (Quad)
3) Battery capacity (mAh) - this value determines storage capacity of battery higher the value higher the battery capacity, higher the flight time .
4) Weight of battery pack : to say easily battery should be as lite as possible for a most efficient multirotor . Even though high capacity battery provides more flight time, you cant use very high capacity batteries because more the capacity, more the weight of the battery. So you should chose an optimum capacity battery whose weight does not go higher than pulling capacity (Thrust) of your motors (Now calculation of thrust for a multirotor is little different it is not simply add up sum of all the motor's thrust  ).

I think i have explained in the min. words possible - so if you don't understand anything, feel free to ask .

Please visit these links :
http://blog.oscarliang.net/how-to-choose-battery-for-quadcopter-multicopter/
http://blog.oscarliang.net/build-a-quadcopter-beginners-tutorial-1/
http://blog.oscarliang.net/multicopter-tutorial-list/
http://blog.oscarliang.net/how-to-choose-motor-and-propeller-for-quadcopter/

thanks, but 25A ESC means the ESC's can supply a max. of 25A ?
And how do i knw how much my 980Kv motors are going to draw how much of current ? Cz Watt rating is not given nowhere !
So that means I can comfortably use a 4000mAh 30C 3S LiPo battery ?

I asked the vendor, n they told bout the motors,
Current at full load: 12.2A
Watt: 150W
RPM: 8500
for 11.1V 3S Lipo on 1045 props.
So now, total current required would be, 12.2*4=48.8 A so can I go with a 4000mAh 25C/30C LiPo ?
cz i want to have more flight time.

Yes you can.

Awesome !
A 4000mAh 11.1V 25/30C should I go with.
Thanks a lot who all helped me out with this.
I'd post my experience.