Don't know. I have no hands-on experience with that brand and just looking at the specs - the wattage just doesn't make sense. No 12V LED that I'm familiar with draws anything near 12W. Mine draw 0.75W each.

The idea works OK and I'm running an automotive system myself because its more robust than bicycle lighting systems and still so light the additional few grams is irrelevant - and the additional durability pays off. But you'll have to watch your batteries. Without a BMS you can accidentally run individual lithium batteries down below 2.6V which pretty much trashes them.

There are similar LED lights on the market already set up for off-road motorcycle use that have built-in voltage regulators and 5.6Ah battery packs that'll run them for 9 hours if disconnected from an automotive electrical system. PM me and I'll point you to a few places.