US Patent 11672068 Lighting device with state of charge based control

A lighting device including a light source, an input device, a power source configured to provide power to the lighting device, and one or more electronic processors. The one or more electronic processors are configured to receive an input signal to illuminate the light source from the input device and determine a first state-of-charge of the power source. The electronic processors are further configured to determine a first illumination output value based on the determined first state of charge and initiate a first ramp-down operation of the light source from the first illumination output value. The first ramp-down operation is configured to reduce an output of the light source as a percentage of the first illumination intensity over time. The electronic processors are also configured to continue the first ramp-down operation until the output of the light source reaches a predetermined illumination intensity.