About the Tabac BCC. I believe it is a step in the right direction because it uses the eGo cone thread instead of the usual 510 thread. However, I believe a brave manufacturer needs to take the evolution of the e-cig a step further and sell a battery with just the eGo cone thread (less the 510 thread).
The world doesn't know it yet, but that's what is needed for the larger cartomizers and tanks that are becoming so popular now. This new standard would make the overall length of the PV about a quarter inch shorter and also reduce the weight. In addition, there's no telling how many new ideas may become possible because of a larger battery thread.
I have been modifying my 1300 mAh batteries like this for some time now. They require a redesigned cartomizer which also has less metal. This cartomizer now has a battery fitting that is simply a thin wall tube with threads inside one end. So it not only weighs less, but is easier to make. The overall difference of the combination is not all that drastic, but every little bit has been adding up to a good bit during the development of my designs of the last year or so.
Yeah, I know. A new battery like I'm talking about is not compatible with the sacred 510 devices that so many us already have. But maybe it's not all that bad. I had to make an adapter for my modified battery so that it could be charged on a standard 510 charger. Low and behold, that same adapter can be left on the battery to convert it to the equivalent of a standard eGo battery with 510 threads.
Although my rig is somewhat large, the Joyetech eCab is a perfect example of how small a device can be with a larger threaded battery. The diameter of the eCab battery is a good bit less than an eGo battery, but the atomizer is the same as an eGo-C tank. For that matter, it ain't all that much larger than a regular size e-cig.
Joyetech eCab, Changeable Atomizer and battery
As seen on this page, an adapter is available for the eCab battery for use with a 510 threaded device. I'd almost be willing to bet that this adapter could be used to charge my modified 1300 mAh battery. If that's the case, then the eCab Atomizer Body would screw on to my battery (I can't tell for certain about the exact thread just by looking at the photos).
Just because I used the eCab as an example doesn't mean that I recommend it. I've never tried one and have no desire to. However, I began vaping with the small e-cigs like most of us did, and would have been a sucker for it had it been available back when I was ready to move up to something a little larger. I think it's a real neat looking little package.