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Unread 19-01-2015, 16:42
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Re: 2015 Beta Testing - The Components are Here.

Quote:
Originally Posted by Ether View Post

Using a simple model of the battery as a fixed internal resistance of 0.011 ohms in series with a constant 12.7v voltage source, it's straightforward to compare the energy wasted across the internal resistance for the same ampere-hours at different currents.

But it's even worse than that. A close look at the battery discharge curves suggests that the internal resistance is not constant, but rather increases substantially with current.
This is not at all surprising. Most resistors increase in resistance as the temperature goes up, like when they have a lot of current running through them. In addition to the reduction in the battery's reduced capability as reflected on the discharge curves, you are also losing more energy to heat in the wiring and the motors at high draw.
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