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Old 01-17-2007, 04:30 AM
  #161  
Mosc_007
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Join Date: Jan 2007
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Originally Posted by kimbalion7
The IB cells have handled 10c and over discharge rates with no problems. Now 10C equates to 42 amp hr per a cell. So 6 IB4200 cells wired in series would equal what? Thats right 252 amp hr at constant discharge and would have to do that to meets safety standards constantly. Simon

Sorry, But you are confusing Parrallel with series and how to calculate the current.

In Series you Add the voltage but the current is the same. In Parrallel you Add the current but the voltage is the same.


If the cells are in series, No matter how many cells. Its still 42 Amps in each cell.

If the cells are in parrallel then with 6 cells it would be 252 Amps. IE, 42 Amps in each cell.

Like I said before. Do the maths with an average Internal resistance for a cell at 252 amps. The terminal voltage would be around 0.2 Volts.


Another way to look at it. If you have 6 4200 mAh cells in Series you still have a 4200 mAh Pack but at 7.2 Volts.

If you have 6 4200 mAh cells in Parrallel then you have a 25200 mAh Pack but at 1.2 volts.

Notice that the mAh rating multiplied by the terminal voltage is constant For the same number of cells. Weather connected in Series or Parrallel.


Charles

Last edited by Mosc_007; 01-17-2007 at 05:02 AM.
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