Reddit reviews Energizer Lithium Button Cell 3V Cr 1632

That depends on the LED, the battery and the circuit. Let's say you get a low current LED (20 mA - https://www.amazon.com/gp/aw/d/B00UWBJM0Q) and an average 1632 battery (130 mAh - https://www.amazon.com/gp/aw/d/B00102JQIE). That's drawing 20 mA from a 130 mA-hour battery so you just divide. You'll get about 6.5 hours of light from it though probably a bit less since you'll want to size your resistor to allow a bit extra current for a brighter light. You would do better getting a 2032 battery - https://www.amazon.com/gp/aw/d/B00DORK4NE. It's only a little thicker and would give you 225 mAh.

Edit: just realized you posted a link to a product. I have no idea how long that would last but i would guess 6 hours would be an upper limit.