The key to finding the best battery
for you is one that can handle enough
AMPS and gives you the longest runtime (mAh).
So as an exapmle, if at your vaping style you draw no more than say 20
amps and you have the following 2 choices for batteries...
Battery 1 - 30A max, 4000mah
Battery 2 - 40A max 3000mah
Then battery 1 will be best for you because 30A is way above you 20A max vaping style and you gain an extra 1000mah (more runtime between charges).
Look at the next-to-last column in this list of reputable batteries to choose from.