Just get the Samsung 25R, can use for anything and best value for money. Never ever use battery < 10A max diacharge for E-Cig, unless u are vaping less than 12W. Study the battery curve.
Those standard non high-drain batteries with max 6A/7A dischage have always been meant for 1A or less usage, for freaking torchlights or other low-current device.
Always take 50% off the max current rating and cal the corresponding power from there. Reason, you know why once you look at how battery discharge their current from the discharge curves (V vs mAH)
At more than 50% of the battery max amp rating, the capacity and voltage starts sudden drop to 3.6V and a steep decline, so only short duration or pulse vaping is advisable, unless you have dual 18650s in parallel. Study all the battery curves carefully and know how to interpret them, then you'll realise what I'm saying. e.g. :
Battery Tests.
Even for my 3 yr old Evic 11W which I used for MTL vape and flavour testing, I have also since replaced with High-Drain battery, reason as explained below. Not only safer this way but last much longer than those rubbish XXXFire bats rated at 6A and below.
SOP on how to interpret battery curves (for Voltage vs mAh) for comparator tests:
1) Select your battery and select the discharge current. ( after calculating using ohm's law)
2) Normal Vaping range is 4.2V down to 3.5V or 3.2V depend on ur regulated mod before cut-off (means lowest battery bar). In general, take 3.6V as reference and see how fast it drops 3.6V at your chosen current.
3) At 3.6V, observe the corresponding mAH value below.
For e.g. for Trustfire batteries, at a mere 5A drain, you can observe it immediately drops to 3.4V with only abt 600mAH capacity, which is horrible.
Whereas for Samsung at 5A, you can vape til no tomorrow. Even at 3.5V, it can vape with 1100 mAH. and can take til 20A drain minimum.
Another good chart is goto
individual tests and observe how the battery voltage at selected current drain vs vape time in seconds, and watch as it drop pass the voltage.
Once you realize this, unless you wanna use for torch lights or vape at <3A or ~6-9W max (Ego-Style), then still safe, else you'll immediately throw all your standard 18650 batteries away, lol.