Abstract: A dynamic battery emulator for replacing and mimicking the characteristics of a battery in a portable electronic device when the device is located in or on a vehicle can include a power control module capable of varying its output voltage to adapt to the voltage requirements of an attached portable electronic device; an input for conveying electrical power from the vehicle's electrical system to the power control module; an output for providing electrical power to the portable electronic device; an output for communicating a control signal from the power adaptor to the portable electronic device to selectively turn on and off the portable electronic device; a battery replacement module configured to replace the battery in a portable electronic device and including battery replacement circuitry for transferring electrical power from the power control module to the portable electronic device via the output for providing electrical power; an ignition sense controller for determining the power state of the vehicl