Another option always on the table is to use the same Handwavium™ that runs the STUN suits, if you don't want to deal with the constraints of modern day technology.
Battery and energy storage is the main problem in tech besides, y'know, getting the concept to work. Scientists have figured out how to create gems from nuclear waste ( !!!!) which themselves emit energy. Can create wearable computers and other tech with it and its gonna be neat
Until I played one of the Carmen games from 1995 with Lynn Thigpen, and I found a note left behind from one of her agents, I didn't realize that Carmen pays her people too Lol