18650 is a size declaration. HOWEVER, Not all 18650s are 650mm x 18mm. some may be 17600 or even 19700. Make sure the SPECIFICATIONS of the batteries you choose match what the DT battery clip says it can fit.
Unprotected cells may fit better but you MUST BE CAREFUL when putting them in as polarity is EXTREMLY IMPORTANT and reversing this may cause detriment to the battery, the device or both.
Any cells with a damaged wrapper must be re-wrapped. PERIOD!
NEVER ever store, charge or use these types of cells without a wrapper.
UNWRAPPED BATTERIES ARE EXTEREMLY DANGEROUS!!!
(even I have fumbled a batt i was wrapping on to a metal surface, once… the battery absolutely shorted out and created a spark near the top of the positive end. the whole body is a negative terminal. that lip at the top is the positive. it does not take much to short these out! oh and that ring at the top? DO NOT LOOSE THAT or you’ll have to buy a whole sheet of em. That ring is just as important as the whole wrapper for safety)
This video below uses a magnet to create a continuous short. do not do this ever!
Your kind words motivate me to continue doing my best around here.
in regards to wrappers.
There are the regular cheap kind. that come precut and often have designs printed on them. These are fairly easy to handle and use while being on the thin side, although this also makes the wrappers easier to cut, nick, rip.
I have a tendency to opt for something more resilient it they are gonna get handled a a lot. Their thickness makes them slightly more unruly to work with but i’ve never personally had an issue with a wrapper like these degrading like the cheaper ones. However it does come on a roll and is not precut, cutting them to size isnt exactly a chore. 5M= ~6 or 7 batt wrappers?
The rings i’ve mentioned not to lose or you’ll need a whole sheet? these are paper with an adhesive back, sure they are not the plastic ones your cells likely came with… with but i’ve found a majority of these do not have adhesive backings and are therefore very easily lost.
XTAR PB2S is the best charger i have… and i have many. works with protected and unprotected cells, features a fast charge option, and can also double as a powerpak
there are templates you can edit and print out, then you just cut and roll and slide the clear PVC sleeve over the battery and label. its tricky thouh