The present invention discloses devices, for adaptive fast-charging of mobile devices, including: a charge-delivering device for providing electrical power to a charge-receiving device; and at least one electrical-contact pin for enabling electrical current to be transmitted at an amperage greater than about 5 A to the charge-receiving device. Preferably, the charge-receiving device is selected from the group consisting of: an integral power-source component of a mobile device and a slave battery. Preferably, at least one electrical-contact pin is further configured to transmit the electrical current at an amperage selected from the group consisting of: greater than about 10 A, greater than about 20 A, greater than about 30 A, and greater than about 60 A. Preferably, at least one electrical-contact pin is spring-loaded. Preferably, at least one electrical-contact pin includes protection circuitry for protecting against thermal overloads and short circuits. Preferably, the device charger further includes: a receiving-area holder for properly engaging the charge-receiving device.