About the Icarian complex that Bataille speaks of, this is a psychological attitude which he attributes to Nietzsche.  There are some passages in THUS SPOKE ZARATHUSTRA which are easy to overlook and hard to understand.   Bataille's interpretation is one thing and the intended meaning of Nietzsche, which is the original one, is another.   Nietzsche observed that people feared breaking from conformity because they realized that it was dangerous.  He encouraged them to do what they felt was dangerous.  His way of speaking was to encourage people not to fear going above and beyond the norm, but rather to see the fact (in his view) that this leads to destruction as a necessary thing and a fundamental confirmation that one had in fact reached certain heights.  The lighting strikes at one BECAUSE one has reached the heights, and would not have struck if one had been lowly and remained lowly.  Therefore lighting strikes are a confirmation that one has become something higher than the norm.

Whilst Nietzsche spoke in a manner aimed at getting people to overcome their timidity, Bataille's interpretation is that Nietzsche's goal in aiming to reach the heights was to be destroyed. Reaching away from the material substance of being and into the reaches of philosophical Idealism and moral transcendence of much of human reality would take its toll.   Bataille reverses the perspective on Nietzsche in a way that is not automatically wrong, but provides a new way of looking at the situation of philosophical Idealism and its costs.

Since Nietzsche's goal was to be in the motion of a constant moral transcendence (until one was struck dead),  and since Nietzsche seemed to succumb to his own prescription by going mad, Bataille suggested a different solution, which was integration of increasingly more knowledge into the psyche, rather than going up to the sun and going mad.   To this end, Bataille proposed a downward movement, which was to be away from the moral heights and into notional "immorality".   By incorporating more knowledge concerning one's fears of "evil", one may even more toward greater psychical health, at the same time as separating oneself from the common embrace of narrow social mores and rigidity.