The LiteSaver Emergency Light is a small, compact emergency light. It contains 21 LED lights. It is plugged into an electrical outlet where it remains ready to provide light when needed. It automatically lights when power is cut off. During normal times, it can serve as a night light, rechargeable flashlight, home security light, and camping light.
Each LiteSaver contains a “smart sensor.” In bright light such as daylight or other indoor lighting, the unit will not automatically light, thus saving its charge for when needed. During a power outage, for example, the light will not turn itself on in daylight, but will turn on when light is later dimmed.
Each LiteSaver emergency light will provide bright light continuously for 8 hours. Using just one LED (the night light), it will provide light for 144 continuous hours.
For details see the Calcellular website.
Other emergency lights are also available. Just ask google.