I made THIS mistake TWICE and then I read here on the forum that:
"Typically - but not always -
if using the 'threaded charging adapter' folks tend to OVER TIGHTEN the battery; they also MAY do this when attaching the battery to the tank - pushing the pin inward." This may or may not apply to your situation.
"The THIN insulating sleeve that surrounds the PIN and holds it in place may or may not be visible, however, you should be able to take a SMALL POINTED "tool" such as a sewing needle or pin and
GENTLY go around and around the pin lifting it a SMALL AMOUNT - perhaps one or two MILLIMETERS. It usually moves EASILY - so do not lift it too far or it CAN come out of the sleeve."
DO NOT PUSH THE BUTTON WHILE USING THE NEEDLE OR PIN as it will create a SHORT and may damage the battery."
"GENTLY screw the battery on to the tank and see if it activates the coil. If not - lift the pin an additional amount and try again."
I realize this may or may not help - but it did help me then and once additionally not long ago. This is the long version of what has already been said in the posts prior to mine; just a different "tool" to lift the pin.
On YOU TUBE (APPLIES TO eGo-C BATTERY -- BUT WORKS ON EVOD AS WELL:
The Center Pin issue! - Fixing a non firing eGo battery - eCigWizard - YouTube
Center Pin Issue - Fixing a non firing eGo battery - YouTube
TAKING IT APART? I personally would NOT do it simply because ONE TINY CHANGE to the PROTECTION CIRCUITS could result in an exploding battery. I'll do the PIN LIFT - but that is all. Soldering that little puppy would be a real pain I imagine.
From Senility Central -- Old Man Don