The Oukitel K10000 is crammed with a 10,000mAh battery, which should hold almost four times the charge of a Samsung Galaxy S6, and five and a half times the charge of the iPhone 6.
A full charge takes about three and a half hours, according to Oukitel, a Chinese gadget maker.
Smartphone software has gotten better at managing apps and programs to conserve battery life over the past few years, but not many manufacturers have upgraded battery capacity itself.
