Stupidity: Why in the world would Tony of all people leave his old suits in storage WITH the miniature arc reactor still inside the suit? This would have served no purpose to Tony since he already has his own arc reactor in his body.
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Suggested correction: This is a question which is easily answered; Tony had the idea of putting someone else in the suit (like Rhodey) himself. Plus, it's logical to think he has built multiple miniature arc reactors, after the events of the previous movie. Plus, he can probably just as easily switch from arc reactor to arc reactor in his chest when changing suits, so he has a fully powered arc reactor ready in each suit.