The present invention provides an electronic device case with a charging mechanism configured to provide backup power to an electronic device. The charging mechanism harvest kinetic energy provided by the user to generate electric current for charging the electronic device, for example in an emergency situation. The charging mechanism includes a spring-loaded retractable handle which when pushed drives a gear set, which in turn drives a dynamo to generate electric current. The case provides a charging connector which is adapted to mate with a charging port of the electronic device to supply the generated electric current for charging the electronic device.