Please excuse me if my terminology is not accurate, or if I'm not asking the right question. I will explain my goal first.

I am building a circuit/device to drain a battery to a specific voltage. I am monitoring the voltage with an arduino and that is opening/closing a relay depending on the voltage.

I need to select a resistor to drain a 3.2v cell and draw 500 milliamps.

Please excuse me if my terminology is not accurate, or if I'm not asking the right question. I will explain my goal first.

I am building a circuit/device to drain a battery to a specific voltage. I am monitoring the voltage with an arduino and that is opening/closing a relay depending on the voltage.

I need to select a resistor to drain a 3.2v cell and draw 500 milliamps.

EDIT:

I am aware that my cells are 3.2v NOMINAL (LifePo4 26650 cells)

Also aware of safety concerns, etc. I'm draining very slowly and under supervision, and in a safe environment.