5054 Blue LED strip question

I have been looking for a way to make a crazy bright saber and wondered about the 5054 Led strips I see around. There is one that is 120leds per meter, which is similar to neopixel density
They are unfortunately 12V
The Crystal focus says it will take 11V
Can it take 11.1V (3x 3.7 li-ion) safely? Or will I have to step it down some how?
I imagine I will have to use a power extender to drive the two strips (like the old Full Powah setup on the 10W LEDEngin)
Sounds like the Power Extender can handle the 11.1V

So combining two Blue LED 5054 LED strips 120leds/meter with a photon blade should make for a bright saber. Any thoughts?

Specifically I want something I can get a good outdoor photo with, assuming overcast skies.

The LEDs will probably light well below 12. They will be parallel strips of 3 in series, so you are looking at something like 1.7 amps for a meter x2 @12v.

The real question is will it light up with 7.4 volts. I don't see a lot of viable battery configuration options. 11.1 li-ion is the easiest to swing, with one of those round AA holders I could get 3 14500 inside a 1.25 inner diameter just fine, and plenty of room in the saber to spare. I saw some high drain LiPo batteries that I think will work. They are used in airsoft and drone flying I think.