Use this guide to replace the worn-out battery in your Google Pixel 2 XL.
'''Before disassembling your phone, discharge the battery below 25%.''' A charged lithium-ion battery can catch fire and/or explode if accidentally punctured.
If your battery is swollen, [[What to do with a swollen battery|take appropriate precautions|new_window=true]]. Do not heat your phone. If needed, you can use a dropper or syringe to inject isopropyl alcohol (90+%) around the edges of the back cover to weaken the adhesive. Swollen batteries can be very dangerous, so wear eye protection and exercise due caution, or take it to a professional if you’re not sure how to proceed.
For optimal performance, calibrate your newly installed battery: Charge it to 100% and keep charging it for at least 2 more hours. Then use your device until it shuts off due to low battery. Finally, charge it uninterrupted to 100%.