I recently bought some new batteries for my 510(wont say the supplier). As soon as I got them I noticed that the LEDs were a lot brighter than the ones that came with my starter kit. I also noticed that the contact for the atomizer was flat, and the ones that came with my kit have a dimple in them. I saw a video somewhere saying that these were the cheaper version. The first two days they were fine, until today. My fiance told me when I got home that her cig was tasting burnt. She topped it off and it got better for a few puffs then had the burnt taste again. I then changed the filler and refilled her cart. Worked fine for a few puffs, then had a burnt taste again. I was vaping mine during this time and noticed that after i had taken a drag I could here some sizzling, like that button was being held down, didn't think much of it. Just now as she puffed her cig, I noticed that vapor continued to come out of the cart after she had taken a drag. I told her it was probably just residual and she puffed it again, without pressing the button. YUCK, all burnt taste! I could hear that same sizzle! The atty was very hot! I quickly removed the cart and the coil was glowing inside the atty! WTF? My question is, could these cheap batteries be staying activated without a button press? Heard anything like this? Sorry for the long post