iPhone X swollen battery needs replacement, help please.

Is it still under the original warranty? If so a swollen battery is clearly a warranty concern.

What you really need to do is take it to an Apple Store if you can. You can specify that it's an Apple Store. Even if it's out of warranty you should be able to get a replacement device for less than the full retail cost, although it won't be like a new device with a new warranty.

Honestly there’s not much that’s going to happen if it’s out of warranty. But I’d still say try taking it to an actual Apple Store for a diagnostic. If it’s not that bad as you state then maybe it just needs a battery. Best Buy doesn’t want anything to do with it, but just give an Apple Store a try.

jongig wrote:

I replaced the battery myself and will not be buying another iPhone again. The battery was easy to replace and I was in a safe environment when doing so.

You have rendered your phone ineligible for any future out-of-warranty services from Apple and possibly ineligible for any potential extended warranty programs.

And, by the way, it is perfectly normal for lithium ion batteries to swell as they age. I spent twenty years in the cell phone industry and have a lot of experience with this. Back in the days of basic phones, the standard way of testing to see if a battery was old was to remove it from the phone and see if it would easily spin on the counter. LG phones were notorious for swollen batteries but we saw it in phones from all manufacturers. For phones with non-removable batteries, Motorola phones seemed to be a big issue.

The genius will be instructed to replace the phone on the spot whether or not it is still under warranty.

Best Buy is not your best option in this case. Make an appointment with Apple to have the device evaluated:

Genius Bar Reservation and Apple Support Options - Apple

I had a similar situation and Apple took care of it at the Genius Bar. They replaced my phone.