Battery Labels Wearing Quickly

Hello I've owned a couple of Sony VTC5's for about 2 months and been charging them with a Nitecore i2 charger. I'm having the problem that on both of the batteries the label/casing has worn away near the negative pole. I'm pretty sure it's the Nitecore charger that's responsible for this. On the charger there is a sort of extendible clip on the negative end for difference size batteries and its almost impossible not to catch the battery on the clip (which is under pressure from the battery) when inserting/removing it.

I was just wondering:
a) How dangerous is this on a regulated mod? I'm using the batteries on a Sigelei 20W. From my understanding of it the wear on the casing could cause a negative/negative short which would mean the spring would not work in the event of an over-current. But it's a regulated mod so presumably it SHOULD be protected at the positive end from such currents?
b) Are certain batteries or chargers notorious for this sort of wear/tear occurring easily? In all honesty at the end of the day I'd just rather switch battery and charger and feel safe.

Picture (not using this one it's so bad):

 

The method I usually use is similar to the one you describe but I obviously was not doing it properly. I just had a practice at trying to use only the terminal of the battery as pressure on the spring-loaded clip thing and I think I see what you mean so I put this incident down to inexperience I think. Thanks for your link on rewrapping batteries, nice to know I don't need to buy a new charger and possibly not even new batteries!

Really, the mod casing actually becomes live if the battery casing shorts out onto it? According to this all of the battery casing is negative and the main problem would be that a hot spring (or negative fuse) would be bypassed if the negative battery casing shorted out onto the mod casing:
http://www.e-cigarette-forum.com/forum/ecf-library/337497-warning-battery-reverse-polarity-apvs.html
Still not ideal admittedly. But maybe a confusion with reverse-polarising where the mod-casing actually does become live/positive and all fuses are bypassed?

 

Thanks for the info. I patched it with electrical tape for now, might do a more permanent repair or get a couple of new batteries later to be on the safe side.