A decent success

問題

Battery capacity had declined to 77% or less due to age/use.

修理

Well enough.

アドバイス

Battery is harder to take out than you think. If you have a reusable heat/cold pack, you can use that in place of an iOpener (I did, heated for 30s in microwave on high, it worked OK). If you have hand or foot warmers that use iron filings for the winter, you can similarly use those. If you plan on doing several device repairs for iPhone 5s or later, I would just go and get an iOpener.