OS X Lion, Moutain Lion, Mavericks, Yosemite: deep sleep on low battery leads to crash I'm having an issue on my Mac since I installed Lion and now Mountain Lion (I thought that the Lion problem could be because I've put an SSD in my Mac and did not make a fresh install but a carbon copy to the new disk, but it still happens with Mountain Lion with a format/fresh install).

What is happening to me is that, when I put my Mac to sleep and the battery dies, it does not restore the state like a normal sleep that it did when I was on Snow Leopard. Now when the battery dies, the computer restarts: I need to put my password and the programs open again but some of them lose the previous state (like VLC, Chrome has the "restore" option, etc.) it is exactly like a restart with the option "Reopen windows when logging back in" selected.

Is this normal or should it happen like in Snow Leopard? 

If this is the normal behavior, I will turn off Deep Sleep since the Mac takes less time to sleep with it off. (I think that the more time is because it is storing the state of the RAM on the disk so it could recover when the battery goes off which it doesn't do properly!)

$ pmset -g | grep hibernatemode
 hibernatemode        3
Does you SSD use a SandForce controller?  SandForce controllers seem to have some serious issues related to battery and sleep/hibernate activities, and you might (I repeat might) be seeing some of these problems coming up:

SandForce controller problems 

If you have a SandForce controller you might want to change SSD altogether, based on the info provided by the link above.