Hi Blaze
I have all
three of the models in question. The threading is the same, but not all pieces are interchangable. I know it is something about polarity - and other than the word, I know nothing. I am sure some electronics wizard will chime in. Something about the direction the power flows through the pieces.
The 902/J118 is a strange and rare beast. It is a cross between a 510 and a 901 IMO - but not compatable with either. I loved mine, great taste, great vapor, but the batts need replacing way too often and hardly anyone sells them anymore. LiteCig is almost always out of stock. IVape.net was selling them but is phasing them out because of the batt issue. Modern Vapor has switched to a different type of 902 which is only kinda sorta compatable with the old 902
You can use a 902/J118/VX2 or a 510 batt with a blu atty, but not a blu batt on a J118 or 510 atty
A L88b passthrough will not power a J118 atty
If you put a blu batt in a 510 charger, you will kill them both. But you can put a blu batt in a J118 charger
There is some magic formula that my sleep deprived brain can't figure out.

And probably couldn't even if I had slept ten hours.
What I always advise people is find a model you like and a vendor (or three) that is good and stick with it. Don't Frankenstein things unless you are an electronics expert. I have given all my J118 stuff to my mom. And I sold my 510 in the classifieds. I use my blu and get parts from blucigs or Volcano. I keep about 6 blu batts charged in a shotglass on my coffee table and a passthrough at the desk. (I'm a chain vaper)
Remember the rule - K.I.S.S. If you have your heart set on a 510 type, Volcano has a new model - the Magma - that is a bigger and better 510 (and I'll take all your old blu stuff <grinz> )
Thanks again for those carts BTW
~A
(off to nappy time)