I need help with the numbers (Voltage, Power, Current, Jigawatts, etc.)

I am trying to determine what type of battery pack I need to drive my Tri-Lux. I will be using a Fatman driver with UWOK LuxIII's.

Here are my calculations from the Fatman tech page:

Power Output = 3 (LED) * 3.51 (low Vf for UWOK) * 1000 (max current)
Power Output = 3 (LED) * 3.75 (high Vf for UWOK) * 1000 (max current)
Power Output Range = 10530 - 11250

Power Input = Power Output / Efficiency
Assume 90% efficiency
Power Input Range = 11700 - 12500

Current Input = Power Input / Battery Voltage
With a 7.2V battery pack
Current Input Range = 1625-1736mAh
With a 8.4V battery pack
Current Input Range = 1392-1488mAh
Assume 11.1V battery pack
Current Input Range = 1054 - 1126mAh


Here are my questions:
Are my numbers correct?
What runtime can I expect?
What battery pack value will increase runtime (voltage or current)?
Why is this so confusing ?

1. Your numbers look correct.

2. Runtime (in hours) = Power_consumption / Power_capacity
eg.
Power capacity of 8.4V pack (low) = 8.4V * 1392 mAh = 11.6928 Wh
Power consumption (low) = 11.700 Watts
Runtime = 11.700 / 11.6928 = 1 hour

3. Average power capacity.
7.2V pack = 12.099 Wh
8.4V pack = 14.1162 Wh
11.1V pack = 12.099 Wh

So the 8.4V pack got the most capacity therefore the longest runtime.
Note the assumption is that under load it will be 1.2V which really does changes depending on battery type/load/capacity/temp/condition.

4. This is not that confusing if you stick around CPF a bit longer

mostly good.. unless you are talking about LIPO pack.. use 10.8V.. 11.1 is not realistic.. also.. use real curves for the MAH of batteries don't assume the 'mAH rating' is accuarte.. example.. the cpb 1650 is a 1.45AH battery and typical consumer '2500' AA cells are good for maybe 2100mAH at moderate draw.

Very good to 'go to watts' to figure things out like this like modamag shows.

-awr

Something must be wrong...

The battery packs I am using for my examples above come from batteryspace.com
7.2V 4800mAh
8.4V 2000mAh
8.4V 4000mAh
11.1V 4000mAh

LED Power Average =
If my LED requirement is 10.9 Watts at 1A, then my power supplied must be 12.1 Watts (@ 90% efficiency).

Although the batteries above probably don't paint a realistic picture:
7.2V * 4800mAh = 34.56 Wh
8.4V * 2000mAh = 16.8 Wh
8.4V * 4000mAh = 33.6 Wh
11.1V * 4000mAh = 44.4 Wh

Am I correct in assuming
Runtime = 44.4 Wh / 12.1 Watts
Runtime = 3.7 hours???

I was thrown off by the original spec "Current Input Range = 1392-1488mAh".
I thought it was your capacity. It should have been "Current Input Range = 1392-1488 mA"

Runtime calculation is correct.

One note though, I recommend the 4800mAh unit (regardless of total voltage) because they use LG18650 (2400mAh) in them.