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Old 03-23-2009, 11:02 PM   #1
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Default Lipo question

I cant seem to dig up the info im looking for. Maybe someone can clarify this for me. I have 2- 11.1volt 3s1p 15c batteries that I have hooked up in series. Now I have output of 22volts but does this mean my 15c discharge rate has increased to 30c now? I would think it would but wanted to see what others have to say.
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Old 03-23-2009, 11:25 PM   #2
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Originally Posted by EMAXX ab USER View Post
I cant seem to dig up the info im looking for. Maybe someone can clarify this for me. I have 2- 11.1volt 3s1p 15c batteries that I have hooked up in series. Now I have output of 22volts but does this mean my 15c discharge rate has increased to 30c now? I would think it would but wanted to see what others have to say.
No, your C rating has not increased and neither has your the maximum discharge rate. If you were to wire the two packs in parallel, the maximum discharge rate would double (assuming both packs are of the same capacity). Here is the formula for discharge rate.

Max Discharge Rate = C rating * Capacity (mah)/1000

Changing the voltage of a pack will not change the C rating.
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Old 03-23-2009, 11:57 PM   #3
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I agree w/ Richard. Your lipo cut off setting may have been too low. you don't want to drain any lipo lower than 80% of your total capacitance or roughly 3.2v per cell. I typically look at the discharge rate and capacity / volume of lipo as a good guage or measurement of the quality of the battery.

For example: if two battery has the same dimensional size and weight (density), but one has higher capacity and discharge rate, it's obvious which is better quality battery.

Lower the quality of the battery, the higher the lipo cut off setting should be.

Ideal cycle for Lipo is to cycle by the capacitance, not by voltage of the battery, but since the voltage is easier to measure it's typically cycled 4.2v to 3.7v or .5v per cell, this way you maximize the performance and the life cycle of the battery.

For better quality batteries, you can drain them much lower (e.g. 2.0v per cell for Kong Power) and not damage or shorten it's life.
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Old 03-24-2009, 05:39 AM   #4
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i agree with pilot, but many companies over rate their lipos. if your not sure stick to what you know.
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Old 03-24-2009, 09:35 PM   #5
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Thanks for the clarification. I knew that parallel would increase your mah and not voltage but for some reason it made sense that if you hook two 11.1v batts in series to get 22v, it should also increase the discharge capability. Now I understand that the discharge capability is only increased when the batteries are hooked in parallel. Cool.
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