I have been constantly having issues with my battery percentage dropping significantly in a short period of time. I eventually decided to do something about it and after doing a little research I decided to purchase the battery and whole toolkit from iFixit it.
I began my repair by viewing the pictures of the guide just to ensure I had all the right tools. I followed each instruction carefully. However, upon attempting to remove the original Apple battery from the phone, I found myself in an issue. I did not follow the correct procedure during steps 21-22 and the adhesive part slipped under the battery and I could not remove the battery at first. I eventually scrolled down and did more troubleshooting type research and found that with a few minutes of the phone being heated by the radiator, a credit card and piece of dental floss, this problem can be solved. After a good while of carefully man handling the battery, I got it off and the repair was smooth sailing from there.
It has been three days later and I am quite satisfied with the repair and recommend it to anyone who is curious about this.
1. Be careful how you pull off adhesive tape under battery
2. Be careful where you put your screws
3. Be mindful of tension put on device
4. Be careful how you deal with battery (fragile)