When the high-power LED lamp bead chip is working, 30-35% of the electrical energy is converted into light energy, and the other 65-70% is converted into heat energy. LEDs are very sensitive to temperature. Generally speaking, LEDs can prevent performance degradation or even failure when the junction temperature is below 125 degrees Celsius. 70% of the faults come from overheating the LED, and the fault rate doubles for every 20°C increase in temperature at half the rated power load.

heat transfer

The heat conduction of high-power LED lamp beads has three basic links, chip to epitaxy, epitaxy to the package substrate, substrate to heat sink or chassis. Now the technical problem of LED heat dissipation is that the LED junction is subject to temperature constraints. Generally, the maximum temperature is 125 degrees Celsius; the planned value is 90 degrees Celsius, and the temperature difference from the ambient air is only 55 degrees Celsius.

High-power LED lamp beads can not be dissipated by fans but by natural convection heat dissipation. What's more, LED heat dissipation planning must also meet the optical needs of LED lighting fixtures. In addition, the LED heat dissipation design must also meet the lighting needs, so as to have a better selling point, and the lighting design restricts the heat dissipation design.

If the high-power LED lamp beads are loosely placed in order to simply dissipate the light source and reduce the optical power, it will not be worth the gain. The cost of LED heat dissipation is very high, and the volume and weight of LED lighting fixtures cannot fill a large amount of high thermal conductivity. Thermally conductive materials, thermally conductive materials include: high thermal conductivity silicone sheets, silicone grease, solder, phase change materials, etc. Among them, thermally conductive silicone sheets and high thermal conductivity silicone gaskets are the most cost-effective and the first choice for thermal conductivity and heat dissipation materials.