I have a 2011 MacBook Pro, with a SSD harddrive that has gotten stuck during El Capitan install. It says the it cannot complete the install, and my SSD drive cannot be repaired using disk utilities. I also have a time capsule that backed up the drive daily, however in recovery mode, time capsule shows no backup what so ever. So today I bought a new external hard drive and formatted it using the directions below off your this site. Next I tried to restore the SSD drive to the external drive and after a couple of minutes it gives an Input/Output error. Now what should I do? I also picked up a new internal hard drive to replace the SSD drive once I get (hopefully) all my stuff off of the orignal drive.
Go back into Disk Utility to format the new drive.
Choose Apple Extended Format (Journalled).
Then click on the Partition Tab.
Choose "One Partition".
Then click on the Options button and select "GUID Partition Scheme".
Then click OK to format the external disk as GUID.
Once that is done you should be able to restore.