Copia batts for BB750?

I am looking at getting one of Mr. Bulk's PM6 BB750 5W Mods. Would the 3.7V 1400mah copia Li-ion batt be good to power this? How would brightness and runtime be affected vs. 2x123's? Wayne?

Here's a good way to calculate required voltage for regulation:

http://home.comcast.net/~theledguy/cpf_store/sandwiches/techical_data.htm

Now, let me practice a bit to see if I understand /ubbthreads/images/graemlins/smile.gif

So for this setup, assuming say 7V forward voltage and 750mA current draw the formula works out like so:

Vin = ((7V * .7) / .8) / 1.5A = 4.08V

So to keep the input current draw under 1.5A you would need to supply 4.08V to the converter board. (I think /ubbthreads/images/graemlins/grin.gif )

Meaning the Copia battery wouldn't allow the board to run in regulation.

Phaserburn:

McGizmo reported that his BB750 shut down after 1 minute when powered by a single Copia 68 mm cell. This appears to be related to the maximum input current rating on the BB750 of 1.5 A.

The L4 appears to be able to draw considerably more current from the Copia.