10 - 30 minuten
My battery was not holding charge very well, needed replacing
At first I was leery that the battery was not new. It looked like it had wear marks on it. Turns out, they were some kind of black-out stuff to cover certain info (logo's?) on the new battery. The Pentalobe tool is not a good fit for the screws, but worked through that, and all else went well. I would buy from Ifixit again.
The tool does not fit down in the recess of the screws, it is slightly too large. You CAN get the screws out with it, but it's difficult. What finally worked for me was steady sturdy pressure on the tool as you turn it. Thank goodness the battery came with cross-tip screws to replace the Pentalobe ones.
Also, work under a magnifying light if you can, the battery connector screws are VERY tiny, and two different sizes!! Make sure you keep them separated upon removal. The grounding prong spoken about in the instructions is also a place of particular concern. It's not easy to see how it is to be installed if you don't get a good look at it coming out.