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Old Mar 30, 2015, 01:03 PM
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My battery build

Attached is a diagram of my stock bat. and the pack I want to build. The 2 batteries in my drawing are identical 14500 1200mAh 3.7V. I took the plastic wrap off my stock pack, so my wiring diagram is identical to it. Its the huge increase mAh I am conserned about, I think it will double to 2400mAh. Will it fry the electronics and burn my copter to the ground or give me extra fly time? Many Thanks To All
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Old Mar 30, 2015, 01:10 PM
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I think you are putting the batteries in series, not parallel.
The result is not increased mAh, but increase in voltage, which will most likely fry whatever you are plugging it in.

And your diagram says your batteries are 3.7, but they are 2cells (7.4). I think you need to do a bit more research before you start blowing things up, or a little better explanation.
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Old Mar 30, 2015, 01:17 PM
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You are correct 2x 3.7 = 7.4v What will the huge increase in mAh do to my copter?
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Old Mar 30, 2015, 01:29 PM
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Be safe son - Fly low and slow
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So your stock battery is 7.4V.

The battery you want to build will also be 7.4V but 1200mAh instead of 650mAh.

The result will be longer flight time, not quite double.
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Last edited by Mad_Mike; Mar 30, 2015 at 01:50 PM.
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Old Mar 30, 2015, 01:41 PM
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The highest capacity 14500 cells top out around 800mAh or so, I strongly suspect your claimed 1200mAh cells are junk.
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Last edited by FiftySlicks; Mar 30, 2015 at 01:58 PM.
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Old Mar 30, 2015, 01:56 PM
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Be safe son - Fly low and slow
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He intends to use 1200mAh batteries in the new pack.
The diagram is untidy and causing confusion IMO.
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Old Mar 30, 2015, 02:41 PM
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Ok, I think I finally understand what's happening.

The more mAh the better, if that was the only thing changing you would just get longer flight times. It's like putting more fuel in the car. The only sad part is that more fuel means also more weight so there is a point where more mAh means so much weight that you actually fly for less, or fly like a pig. Finding the perfect balance is not easy!

Good luck!
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Old Mar 30, 2015, 03:24 PM
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Quote:
Originally Posted by russert122 View Post
You are correct 2x 3.7 = 7.4v What will the huge increase in mAh do to my copter?
May I suggest you read this: http://www.tjinguytech.com/charging-how-tos

But briefly:
Adding cells in series does not increase the mAh.
Adding cells in parallel does increase the mAh.

Adding cells in series does increase the voltage.
Adding cells in parallel does not increase the voltage.

Adding mAh does not force more current into the motor.
Adding voltage will increase the current in the motor.

Glen
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Old Mar 30, 2015, 10:39 PM
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Thanks a lot for all the info
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Old Mar 30, 2015, 10:55 PM
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Originally Posted by Pass1 View Post
The only sad part is that more fuel means also more weight so there is a point where more mAh means so much weight that you actually fly for less, or fly like a pig. Finding the perfect balance is not easy!

Good luck!
Or, not be able to fly at all. Before you start building a battery, I suggest you find out how much heavier the battery will be than the current battery, and attach that much weight to the model. Then you'll know how it will fly with the extra weight, if it flies.
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