Samsung may not have left its battery troubles completely in the past. YouTuber Mrwhosetheboss (aka Arun Rupesh Maini) and others have noticed that batteries in Samsung phones are swelling up at a disproportionately high rate. While this most often affects older devices where ballooning batteries are more likely, some of them are only a couple of years old - the 2020-era Galaxy Z Fold 2, for instance. It's usually obvious (the phone back pops loose), but it can be subtle enough that you may not realize your battery is in a dangerous state.
Battery swelling isn't a new problem, or unique to Samsung. As lithium batteries age, their increasingly flawed chemical reactions can produce gas that inflates battery cells and increases the risk of a fire. This author has had two non-Samsung phones meet their ends this way. It's more likely to happen if you leave a battery without charging or discharging for a long time, and many companies (such as Apple) recommend that you keep batteries at a roughly 50 percent charge if you won't use a device for extended periods.
The concern is that swelling appears to affect Samsung phones of the past few years more than other brands, and that the power packs are rated to last five years without hazards like this. Tech video creators are uniquely well-suited to track issues like this - Maini and people like him often store dozens or hundreds of phones in identical conditions, although they don't necessarily keep the handsets at appropriate charge levels.
It's not clear just how broad the problem is, or how systemic it might be. We've asked Samsung for comment and will let you know if we hear back. However, it's safe to say the company would rather not deal with more battery woes. The Galaxy Note 7's fire-prone battery led Samsung to conduct a massive recall that (temporarily) tarnished the firm's reputation. With that said, the crisis also prompted a focus on battery safety and served as a warning sign to the phone industry. If nothing else, the swelling reports could educate users and manufacturers.