A portable lighting device includes a housing, a light source supported by the housing, and an alkaline battery positioned within the housing and coupled to the light source. The alkaline battery is configured to provide a drive current to the light source, and an intensity of the light source is dependent on the drive current. The portable lighting device also includes an electronic processor positioned within the housing and coupled to the light source and the alkaline battery. The electronic processor is configured to monitor a voltage of the alkaline battery, and execute a ramp-up algorithm to control the drive current based on the voltage of the alkaline battery.