Are there LED night lights that also have an emergency light capability when the power goes out?

I like LED night lights (or "passage lights", as some are labeled) that turn themselves off in daytime. It would be nice to find such a light that also had some capability as an emergency light, one that would come on if it was dark in the room and the power went off. It would be even nicer to find such a light that used a standard rechargeable battery instead of a built-in battery.