When mobile phones are frequently used or played games, the internal heat of mobile phones will become very serious, especially chips, batteries, etc. On the one hand, too high heat will cause discomfort when holding the phone, on the other hand, the performance of the phone may be affected, even restart or crash. Therefore, in order to let the heat of mobile phones dissipate more quickly, many mobile phone manufacturers will attach graphite fins to mobile phones, which is often referred to as graphite heat dissipation.

Heat sink, also known as thermal conductive graphite, is a new type of high thermal conductivity heat sink material. Its chemical composition is mainly a single carbon (C) element, which is a natural element mineral. Thin film macromolecular compounds can obtain graphitized films under high temperature and high pressure by chemical methods. Although carbon is a non-metallic element, it has the conductivity and thermal conductivity of metal materials, and also has the same plasticity as organic plastics. In addition, it has some good process properties such as special thermal properties, chemical stability, lubrication, and coating on solid surfaces, Therefore, thermal conductive graphite has been widely used in many fields, including our aviation, national defense, photos and electronic products around us.

The traditional heat conduction materials are mainly metal materials, including copper, aluminum, silver, etc., but the density of metal materials is large, which will undoubtedly increase the weight of mobile phones. In addition, from the figure below, we can see that the thermal conductivity of graphite in the horizontal direction is 1000-1500W/mK, which is much higher than that of silver, copper, aluminum and other metals (for example, the thermal conductivity of silver, copper and aluminum are 430W/mK, 400W/mK, 238 W/mK respectively)

In addition, graphite heat sink has some advantages that metal cannot reach. It can be attached to any flat and curved surface very smoothly, and can make any form of cutting according to customer needs. His pasting and cutting processes are much simpler than metal.

Now we have seen the technology of graphite heat dissipation on many brands of mobile phones, including iPhone, LG, Xiaomi, ZTE, etc.

Graphite flakes on iPhone back cover

The iPhone also has graphite heat sink on the chip