Answer to "Battery is not recognized after replacement"Macbook Pro Retina mid 2013. Had very same issue. New battery would not get recognized, computer would shut down after unpluging magsafe. What interesting is that if I would boot it with magsafe connected, and disconnect magsafe once apple logo appears, it would keep booting, and then right before OSx login, it would shut off. After hours of trial and error , I booted mac with my old battery, logged in. Then, disconnected battery while mac still runs on the magsafe. Then connected new battery and this solved a problem. Battery recognized and showed me cycle count of 1. Note, when I disconnected the old battery, while magsafe still connected, mac vent to sleep mode, but I proceeded with connection of the new battery while it was still plugged to the magsafe. Hope this helps.