I'm new to the vaping world, got my first kit a couple of weeks ago. I thought I had some dead carts & just for grins I attached to my passthrough & they acted like they were brand new. Put back on a fully charged battery....nothing. Are my batteries the problem or is the passthrough just that much better at getting the last bit of juice from the carts. BTW I never got that "burnt" taste from any of the carts I thought were dead. Just nothing, no taste and no vapor.