There are lots of good suitable batteries available..Imren, Samsung, MXJO, Sony, LG, Efest, AW, Vamped, PVTSO, Lavacell, MNKE...though most of them are simply rewrapped batteries of one of about 4 battery makers. Just don't believe the mah or the amperage listed on the battery...most of the time the amperage listed on the battery is for pulse amperage and not continuous amperage. Also beware that there are 'fakes' of the most popular batteries that say they are one thing but really aren't (Sony and LG are the most copied). Also know that most of the rewrapped batteries, even when the company name on them is trusted, are often what is referred to as 'lesser bin' batteries, in other words, batteries that the major manufacturer didn't see fit to put their own name on for one reason or another, but are still suitable for most purposes, including all but the most strenuous use of them in a vaping mod. Stick with the most reputable vendors, the ones who have been in business for several years, and your local retailer who buys from such vendors of batteries, and you should be fine.