Tonight, when packing away one of my radios, a Radiwow R-108, I noticed that the rear battery door had popped off. I looked at it more closely and discovered that the radio's BL-5C lithium-ion battery had swelled enough to force the door open. Obviously, I removed the battery, as a swollen lithium-ion battery is indicative of dangers with the battery. I found this to be unusual because I've had good luck to this point with BL-5Cs, much better luck than 18650s. But it looks like something I'm going to have to watch out for in the other radios using BL-5Cs that I have, especially the Tecsun PL-320, which I like a lot despite its use of a lithium-ion battery. Anyway, something to keep in mind.