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FAA (US governing body) and IATA (International Governing) do not allow checking lithium batteries, so if you're flying INTO the US, you cannot check a lithium light. Since every US airline requires you to carry on lithium, you see the issue here....
Just to be clear, that applies to "loose" lithium batteries, not batteries installed in equipment:
Safe Travel with Batteries and Devices | Transportation Security Administration
My reading is that you can check your lithium battery-powered devices so long as the battery is installed in it rather than separately packed. I believe the perceived danger is sparking at the terminals.