Li can also mean "plum" or "pear" in Chinese - depending on its tone - and can be used to form such names as "Li Hua (flower)", which means "pear blossom."
I've seen this name used in two different series. In Avatar: The Last Airbender, this is the alias Zuko uses while in the Earth Kingdom. In the anime Darker Than Black, the protagonist Hei uses this (sometimes spelled as Lee) as his civilian persona.