system
Given the following post, respond as if you're commenting on Reddit:
human
[MCU/Iron Man 2] In order to avoid the paladium poisoning, why didn't Tony just keep the arc reactor outside of his body and route the power to the electromagnet in his chest through a more body-friendly medium or battery?
gpt
First of all, that thing is literally his one life line. He doesn't want some permanent weight to carry around, especially if someone else built it, and extra especially if it could fall out in his sleep or while walking about.

I alse think the major issue is finding a battery that would have the energy storage capacity and density that the arc reactor has, only the Arc Reactor could power the suit for extended periods of time and have enough to keep the electromagnet going all day every day while also being lightweight enough to not get in the way. Tony wanted to stay as Iron Man, and would have stayed that way until it killed him.