LED Light Panel battery ( NP-F750 / NP-F970 )

I purchased a panel LED light for my projects and while it can be powered by 12v barrel jack it can also take a battery ( NP-F750 / NP-F970 ). However these are quite expensive so i thought i'd design my own. I had started from scratch then a friend pointed me in the direction of the battery adaptor from adafruit so i used that a base and then modified it to my needs. The lid is a friction fit but could easily be glued if required.

The case is designed to fit four 18650 batteries running in a 2s2p configuration so batteries shall be 8.4v when fully charged. I've reused cells from dead laptop batteries paired with a 2s BMS. For the terminals i used a strip of nickel which i bent into a triangle and then placed it through the holes in the bottom of the case. When soldering it all up take care to note the correct polarity, shorting 18650's is very dangerous.

http://s.click.aliexpress.com/e/bKNFZqys

The battery adaptor is here https://www.thingiverse.com/thing:1181132