it could be however if the blade is initialized and even starts, then the board is driving it. I would rather test with first a lower number of pixels and / or with lower channel values / single color. While the white is a serious current draw, a single color should be fine with any cell, I've even used crappy / cheap ultra fire (red/black series) and they do power 220+ pixels (but the sound is bad due to voltage ripple).
If you get a power shortage, there a huge chance your power supply path gets broken. Recharge port or battery PCB, imho.