Welcome to BLF.
The Sanyo NCR18650GA http://www.illumn.com/batteries-chargers-and-powerpax-carriers/18650-sanyo-ncr18650ga-3500mah-high-discharge-flat-top.html, is the same battery that’s inside the Keeppower in you link, It’s not protected like the Keeppower, but the flashlight have build in protection.
I don’t know about you knowledge with Lithium-ion battery safety but here is a great tread to get some info Lithium-ion battery safety 101