Patent ID: 8820976

Claim:
A method for passively cooling at least one light-emitting diode (LED) (i) having an LED die that generates light and heat when electrical power is applied to the LED and (ii) being mounted on an exterior surface of a wall of a heat exchange medium container having an inner cavity volume at least partially filled with a liquid heat exchange medium (a) sealed within the heat exchange medium container and (b) in contact with a heat-receiving portion of the wall within the inner cavity volume opposite the LED, the method comprising: applying electrical power to the LED to operate the LED, whereby heat generated by the LED during operation is received through the wall by the liquid heat exchange medium and drawn away via convection without pumping or consumption of external power to move the liquid heat exchange medium, wherein the heat exchange medium container is configured to have a portion of the inner cavity volume disposed above the LED regardless of the physical orientation of the heat exchange medium container.