PORTABLE POWER SOURCE WITH LOW POWER DISPLAY

A portable power supply including a housing, a circuit, a battery power source, and an electronic-ink display. The housing supports a battery power source and a power outlet. The circuit is supported by the housing and includes a power input from the battery power source, a power output on the power outlet, and an inverter electrically connected between the power input and the power output. The battery power source includes a battery cell electrically connectable to the power input. Power is transferrable from the battery cell to the circuit to be output through the power output. The electronic-ink display is configured to display one or more parameters associated with the portable power source.