t5 lamp

My T5 lamp cord accidentally got cut in half. Am I able to reconnect it with wire caps or should i replace the whole power cord?

you can just reconnect it the regular way by rolling the cords together the right way and putting wire insulation to it. this will cause really insignificant power loss if any, probably undetectable difference

If it is the regular 2 conductor zip cord, I would use butt splices and some shrink tubing over it. I would stagger the slices to make the cord as streamlined as possible.