"Invisible Heat-dissipating Guardian" in Mobile Phone: Artificial Graphite Sheet

"Invisible Heat-dissipating Guardian" in Mobile Phone: Artificial Graphite Sheet

Playing two popular hand games, the mobile phone is as hot as a "small stove"; After a long video call, my back is too hot to hold ... Cell phone fever has become a high-frequency problem for contemporary people. When the mobile phone processor, battery and other components continue to "have a high fever", not only the performance will be greatly reduced, but also the service life may be affected. It is the artificial graphite sheet called "invisible heat dissipation guardian" that silently fights against high temperature inside the mobile phone.

Artificial graphite flake is not natural graphite, but is made by high molecular polymer (such as polyimide film) through high temperature carbonization and graphitization. Under the microscope, it presents a unique lamellar structure, and the carbon atoms are arranged in a hexagonal lattice. This special microstructure gives it amazing thermal conductivity. Although the thickness is only 0.05-0.3mm, its in-plane thermal conductivity can reach 1500-1800 W/MK, far exceeding that of metallic aluminum (237 W/MK), which is called "heat dissipation black technology".

The heat conduction inside the mobile phone is a battle against time. When the processor, 5G chip and other components work, the artificial graphite sheet will quickly absorb heat like a "heat sponge", and then use its two-dimensional thermal conductivity to evenly spread the heat to the mobile phone case. Taking Snapdragon 8 Gen3 processor as an example, the core temperature can be reduced by 8-10℃ in the game scene with artificial graphite chips, which effectively avoids the jam caused by overheating.

In the precise internal space of mobile phones, artificial graphite sheets are almost everywhere. As a "big heat generator", the processor is usually covered with multiple layers of graphite sheets, which work together with vapor chamber to quickly export the core heat; When the battery is charged quickly, it is easy to generate heat accumulation, and the graphite sheet can disperse heat in time to prolong the cycle life of the battery. Even the "small heat sources" such as 5G antenna and camera module are wrapped with graphite sheets to ensure the uniform temperature of the whole machine.

Compared with traditional heat dissipation materials, artificial graphite sheet has incomparable advantages. Its thin and light features make mobile phone designers love it-the thickness of ——0.1mm hardly takes up space, but it can achieve efficient heat dissipation; Flexibility allows it to perfectly fit complex structures such as curved screens and special-shaped motherboards; Coupled with controllable cost and strong mass production, more than 90% of flagship mobile phones now list it as standard.

However, as the performance of mobile phones continues to soar, artificial graphite sheets are also facing new challenges. In the face of the upcoming 2K 144Hz high-power components such as screens and AI chips, it is difficult to meet the heat dissipation requirements only by graphite sheets. The industry is exploring to combine it with graphene, VC vapor chamber and other materials to break through the bottleneck through a multi-layer composite cooling scheme. From 4G to 5G, from ordinary chips to AI computing units, artificial graphite sheets have always been the backbone of mobile phone heat dissipation. In the future, with the popularity of folding screens and wearable devices, this "invisible heat guard" will continue to evolve to protect our smart life. The next time the mobile phone is hot, imagine that this material as thin as cicada's wings is fighting fiercely with high temperature inside.