I purchased my iPhone 5s back in 2013 and kept the phone in pristine condition since day one. I thought by ensuring it's care, I would have a product that would stand the test of time. Boy, was I wrong. Over time, I noticed the battery life would slowly diminish - growing weaker and weaker. This became increasingly apparent when I would snowboard. A fully-charged battery would drop to 3% then all of a sudden die during a full charge. I knew something was wrong.
After watching a few videos on YouTube, the disassembly went rather smooth. For my first time taking the screen off, it was hard to gauge just how much force was required to lift with the suction cup provided in the battery kit. I drew a diagram of the internal components of my phone along with indicators to where screws were to be inserted.
The hardest part was removing the adhesive strips. While I was able to cut the strip in two, both sides ripped as I carefully pulled the strips away from the battery. With a little effort using the nylon tools provided in the kit, I was able to free the battery after brief applications of heat to the underside of the battery area.
As soon as I removed the battery, reassembly was simple. I ran into some issues with the display being distorted from excessive pressure due to weird fittings of either the battery cord or the adhesive strip tab. I wish I knew to tuck and fold the tab so that it wouldn't push on the underside of the display.
I sealed the phone shut, turned it on, and all was in working order. I no longer have to worry about charging my battery excessively any more.
I found it helpful to draw a diagram of my phone to arrange the screws and covers I removed. This helped establish context to which screw went where. Fold and tuck adhesive tab so that it doesn't press against the display. Neatly tuck battery wire into crevasse for similar reasons.