It is known to contain the maternal part of the soul of.
Unit 00 is also equipped with retro rockets as shown in the fight against Matarael.
Back in the present, Misato is forced to kill Kaji at the end of the episode.
While there are synopsis of it online, Western fans have to wait until they actually see it.
At the conclusion, Unit 01 is left floating adrift in space, fossilized and still containing the soul of Yui Ikari, an eternal testament to the existence of humanity.
This also offers an explanation for Kaworu's instantaneous and unwavering devotion to Shinji--he's lived through these other timelines and still has all the feelings towards Shinji from those worlds.