A resistive curve would be helpful to a point. Remember that resistance will change with temperature, so take a temperature reading when you create your curve. In fact I would suggest that you do two curves, one at 70 F and another at 110 F. (21 C and 43 C respectively)
That way you will be able to calculate what your current draw will be at start and after the cell warms up.
Of course if you are using a PWM then the second is not as important.
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Some days I get the sinking feeling that Orwell was an optimist!