It's the same supplier (pretty sure).
So you've got two problems:
1) old tanks short the new battery
and
2) you get less vapor from the new tanks
#1 need more info: does the new battery light blink when you try it with the old tank? Is the center post on (under) your old tanks perfectly centered?
#2 that's actually normal (but can be fixed).
The vapor production depends (among other things) on the wicks, and the placement of the sleeve over the coil. Try loosening the sleeve a bit (although usually we have to do the opposite; new coils are normally loose, and leak).
Also, the juice itself can be a factor, even the same juice, but from a different bottle. Did you use the same juice from the same bottle?
There's also an odd chance that something is wrong with the coil. If you do a dry burn, the whole coil should light up, like this:
(actually, that coil was shorting out, in the middle, and died shortly after I took that pic)
(Do it only on a dry wick, but don't do it for more than 2-3 seconds)
If only part of the coil lights up, then the coil is bunched up, causing it to short out on itself, or it's touching the side of the coil assembly. You can work the coil over, but do it gently; it's a bit fragile.
If you have a meter, you can measure the resistance of the coil; it should read 2.2 - 2.4 ohm. If not, it's either the wrong coil, or something's wrong with it.
