Have you considered how the cells will hold up to 2 years of charge / discharge cycling? 30Q’s will likely be better performers for half that stated lifetime than any 3500mAh cells will. The 3400/3500mAh cells degrade from cycle count faster than good old 30Q’s…

What you should do is get contracted now to provide replacement cells in a years time.

Also, whenever I would provide li battery powered lights to a police dept / agency I would always include a laminated “cheat sheet” on safely handling li batteries to be kept with the charger and I would also try to give a few different guys (on different shifts) a short in-person safety brief so atleast someone had some first hand instruction.

Do they know the basics like don’t leave cells sitting in the charger after the charge is complete and not to force the light to run after its tried to shut itself down cause of LVP kicking in (many many people not well-informed do this, not just cops, hell I’m constantly yelling at guys on my job sites to take 90 sec to swap batteries instead of trying to continously bump the output back up after a LVP step-down, and they know better).