The LiPo Paradox
This term was coined in airplane circles when it was discovered that a 1000mAh lipo pack would actually give longer flight times than a 1000mAh NiMH pack. You would think a mAh is a mAh, and that the battery chemistry doesn't matter, but it actually does! The reason why is two-fold. Speed controls work by sending very short pulses of full power to the motor. When one battery has a lower internal resistance than another, it maintains a higher voltage during the speed control’s pulses, and the actual throttle level required to maintain the same speed is lower. In addition, LiPos have a much higher surface charge due to their different chemistry, and can regenerate that charge faster than NiMH cells after each pulse. So again, the observed effect is a lower throttle level to achieve the same speed/power with a NiMH pack, which allows the LiPo pack to run significantly longer than its rated capacity would suggest. It's strange but true!
原來相同mAh, LiPO都耐力D. |
