It could work with 4s, but that would probably shorten the life span of the light also that light is already bright as shit lol.
Yeah. It wasn’t his intent to do that
where did you get this? Also i have never used a BMS how does it work?
I got the laptop batteries free from a friend. Then to wire I just googled 3s BMS and one of the images shows you how it goes.
The BMS prevents over charging and over discharging. Also balance charges the cells
like this but just in series? 
That is series. That is 3s1p. Mine is 3s3p so same picture but three batteries in parallel instead of one.
I am sorry i meant to say parallel, it is almost 6:00 am here lol. what did you use to connect in between batteries that connects to BMS
if i wanted to permanently mount this into my enclosure would i just need xt90 y connector at the battery so one goes to light other mounted into enclosure for charging?
Yes they were spot welded. I just changed the shape of the pack. The BMS that’s attached to the laptop pack has to come off. Then the basic one can be wired in its place
awesome yah i found a video on youtube showing you how to disassemble it. looks really easy.
Yes. Or unplug the light and use that lead. You can use a smaller connector if you want. The light draws like 2a
ok awesome what connector would you use?
I used a xt60 because I have them. For you I would just use whatever is compatible with your board and charger.
so basically i would have to buy connectors the imax B6 came with a xt60 to bullet connector. so i guess i should just buy xt60 for ease of use.
I use lots of xt60s because that’s what my chargers use.
I don’t see why not. It should work just fine. I’ve never used one.