Your battery’s not fat, it’s just dangerously swollen

My OnePlus 9 Pro battery is so swollen it split open the case.

I discovered this potentially dangerous situation by accident when I noticed the one-year-old Android phone sitting imperfectly in its carbon-fiber case. Absentmindedly, I reached over and pushed one corner of the phone down, trying to reseat it. It popped back out. After a few attempts, I removed the case and discovered the truth: The battery had expanded and split the chrome case along one long-glued seam, creating, in one area, a quarter-inch chasm.



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