Heatpipe and vapor chamber cooling application in Cell phone

     With high performance and long endurance, mobile phones in 5g era have higher requirements for thermal management system. In the 4G era, the thermal management of mobile phones is mainly based on graphite sheets. In the 5g era, heat pipes , vapor chambers will be the mainstream. Some high-end models may use graphene as the material of the thermal management system.

      The heat pipe is generally composed of evaporation section, insulation section and condensation section. Its heat dissipation path is: the heat generated in the terminal is transmitted to the heat pipe through the heat conduction interface material. The heat pipe quickly transmits the heat to the copper foil and evenly disperses it. The heat at the copper foil is further transmitted to the heat dissipation graphite film and disperses the heat in the plane direction.

      Vapor Chamber, Compared with the heat pipe, its conduction mode is upgraded from one-dimensional linear conduction to two-dimensional plane conduction, and the heat dissipation efficiency is improved by about 20% - 30%. In terms of application scope, the heat pipe matured earlier and the cost is relatively low. In the early stage, it was mostly used in the fields of server, notebook, led and high-power IC. At present, it has been extended to some medium and high-end mobile phones; The production cost of VC is relatively high and its mass production capacity is weak. At present, its application is limited to high-end notebooks and medium and high-end smart phones. Under the background of ultra-thin, lightweight and continuously upgraded performance of consumer electronics, heat pipes and VC are expected to give full play to their advantages in thermal conductivity and continuously improve their permeability.

     5G cell phone will adopt the combined cooling scheme, and the incremental space of mobile phone cooling system is significant. The demand of 5G mobile phones for mobile phone cooling system has increased. At present, most of the released 5G mobile phone models are equipped with metal cavities such as heat pipe / VC, in addition to graphite sheet / graphene as heat conducting sheet, so as to realize rapid heat transfer.