I had my first one die recently, got it in February. The last week or so before it passed on, it wasn't holding as much of a charge. Where as before it would last longer than I could vape it in a day, it started dying at 8 pm, then 6 pm, then 4 pm, then it didn't have a charge at all. I plugged it into the charger, and the button would blink, but the charger didn't change colors. I'd take it off, press the button, nothing, no lights, no vape. It was 1 of 2 I got in the kit, the other one still being practically new since I always just used the other one. I have 2 650s in reserve as well, so I should be good for awhile. Not sure if that info helps at all.