I just ordered another Zero. My first one has lasted me for about a year. This includes recharging it at on average around 1.5 times a day. Only now is its internal battery not quite taking a full charge. Only recently and while charging, it now only shows red (still charging) and never shows green which indicates fully charged. Yet when unplugged, it shows green which means that it still obtained a high level of battery charge (at least over 50%). The upshot is that the internal lithium battery is good for at least 500 charges. I am very impressed with the Zero's functionality, build quality and reliability, and the longevity of its built-in lithium battery.
The team was swift in assisting me when there were payment problems as well as mailing issues. Very happy with my products. If you vape almost all time, everyday, I'd recommend buying more pod refills because mine last me about a week and a half before the flavor and cloud volume noticeably go down. Would buy again!