Poflex Technology Co., Ltd

why do led headlights get hot？
Because the electrical energy is not completely converted into light energy, but a part of it is converted into heat energy, and the electro-optical conversion efficiency is 20~30%. About 70% of electrical energy is converted into heat energy. Specifically, the high temperature of LED lights is caused by two factors: the internal quantum efficiency is not high, and when electrons and holes recombine, 100% photons cannot be generated, which is usually called PN caused by "current leakage". The recombination rate of regional carriers decreases.

The leakage current multiplied by the voltage is the power of this part, which is converted into heat energy, but this part does not account for the main component, because the internal photon efficiency is now 90%. The photons generated inside cannot all be emitted to the outside of the chip and are finally converted into heat. This part is the main part, because the current called external quantum efficiency is only 30%, and most of it is converted into heat.

http://www.poflex.com/article/en/The-best-heat-conduction-led-headlights-for-cars.html