Some Apple Watch batteries are expanding for some reason, but don't panic

If you have an original Apple Watch with a swollen or expanded battery, some good news: You're now eligible for extended repair coverage.

In a note obtained by 9to5Mac, Apple has quietly updated its service coverage for original Apple Watches for an additional two years beyond their 1-year limited warranty.

The swollen battery and extended warranty appears to only apply to original Apple Watches. Series 1 and Series 2 Apple Watches (both released in 2016) should be fine.

While reports of Apple Watches with swollen batteries aren't widespread, the few images shared online suggest the damage can be quite insane. Just look at this Apple Watch screen that reportedly popped right off a user's wrist while she was wearing it:

This Apple Watch isn't quite as damaged, but you can still see the screen popped off:

Original image has been replaced. Credit: Mashable

One Reddit user named "matdotcx" shared his experience:

Just after 00,25 I woke up to a pop sound from my nightstand - and my 38mm SS Series 1 lighting up. Instinctively, I pick it up and it's hot - not burning but warm enough that it's noticeable. And then as I tap the screen, I notice it bounces… turn on the lights, and low and behold, the screen has come away from the case at the bottom, with what I can only assume is a swollen battery underneath.

Frightening as that sounds, there's probably no need to be alarmed. Given their smaller batteries, it's unlikely Apple Watches will follow in the Samsung Galaxy Note 7's footsteps and start exploding left and right. It's unclear what exactly is causing some Apple Watch batteries to expand; any number of factors including impact or water damage could be the reason.

Still, it's another reminder that all gadgets with lithium-ion batteries are volatile and potentially dangerous, no matter how many safeguards are in place.