Well, looks like one of the older 18650 cells used in my flashlights is getting rather warm while charging, and shows degraded performance in my lights even at high charge levels. That means high internal resistance. It's still charging, though, and I can still get decent runtime out of it when the light is run at lower output levels.
Do I retire the cell, or continue to use it?
The temperature it's reaching is not dangerous. It's hitting about 35 °C when charging at about 1A.
The behavior of the battery is otherwise normal: it doesn't exhibit unusually high self-discharge.
I don't have any instrumentation that can actually measure internal resistance.
I'm trying to figure out how to increase the maximum length for a GET request for an app service hosted on Azure. Is that a question for Super User? Stack exchange? Neither?
