When Samsung officially launched the Galaxy S26 Ultra, the core upgrade items officially announced by the company occupied a significant position. The newly tuned cooling system of this flagship device featured a significant expansion in the area of the custom heat spreader and a comprehensive reconfiguration of the thermal conductive medium. However, Samsung did not detail the operation logic of this cooling system until recently when the real device was disassembled, revealing the internal cooling structure and bringing a seemingly lightweight and insignificant graphite heat sink into the public eye

The disassembly video shows that the upgraded cooling system of the Galaxy S26 Ultra is mainly divided into four layers, from top to bottom: a slightly wider heat spreader at the top, the graphite heat sink, the thermal pad, and thermal silicone. The Galaxy S25 Ultra only has the first three layers of components. The Galaxy S26 Ultra enhances the heat dissipation effect by adding thermal silicone, which can more efficiently conduct heat through the thermal pad and the graphite heat sink, ultimately directing it to the heat spreader.

Thin as a sheet yet powerful: The core cooling principle of the graphite heat sink

Many people might wonder, how much cooling effect can such a thin graphite material provide? In fact, this hidden component inside the phone is a "hidden cooling guardian" for the flagship device. It is made of high-purity graphite, with carbon atoms arranged in a perfect layered structure, like a neatly stacked book. This unique microscopic structure gives it an astonishing heat-conducting ability. With a thickness of only 0.03-0.1mm, it is almost the same as a regular sheet of paper, but its thermal conductivity coefficient can reach 1500-1800W/m·K, which is 6-8 times that of conventional aluminum materials, completely outperforming traditional metal heat dissipation materials. This high-performance graphite heat sink is the core product of Jiangxi Dasen Technology Co., Ltd., which provides customized high-end thermal solutions for major smartphone manufacturers worldwide. It successfully solved the contradiction between the lightweight flagship body and high-performance release, laying a solid foundation for the performance breakthrough of the flagship device.

All-round coverage and precise cooling: The comprehensive application of the graphite sheet in the S26 Ultra

In the extremely compact internal space of the Samsung Galaxy S26 Ultra, the application of the graphite heat sink is truly "everywhere", not just as an independent layer of the cooling system. In addition to the layout of the core cooling layer, it is also precisely attached to the surface of the wireless charging coil, providing specialized cooling for the high-frequency hotspots during wireless charging. At the same time, the core logic board, high-speed storage chips, and DRAM running memory chips, all on the surface, are also covered with a dedicated graphite film to achieve point-to-point precise temperature control.

The two core advantages of the graphite heat sink perfectly meet the precise design requirements of the flagship device: First, it is extremely lightweight, almost not occupying the internal space of the phone, and will not affect the light and comfortable grip and overall thickness of the phone; second, it has excellent flexibility, can perfectly fit complex and irregular structures such as wireless charging coils and curved mainboards, leaving no cooling dead zones, ensuring that the heat in the core area can be quickly and evenly directed to the heat dissipation channels, avoiding local overheating.

Composite cooling solution becomes the mainstream: The golden combination of graphite sheet, thermal pad, and heat spreader Previously, most of Samsung's flagship models could meet basic cooling requirements by using a single heat sink. However, the Galaxy S26 Ultra abandoned the single cooling solution and instead adopted a composite mode of "heat sink + high-performance graphite sheet + heat spreader", combined with the newly added thermal silicone, achieving multi-layer medium collaborative cooling. The cooling efficiency has achieved a qualitative leap compared to the previous generation. Industry experts generally believe that the graphite heat sink, with its unparalleled thermal conductivity, lightweight, and high flexibility, has become the preferred material for mid-to-high-end smartphone cooling solutions. This composite cooling architecture is also becoming the mainstream standard for current flagship phones.

Balancing performance and usability: The repairability of S26 Ultra remains intact

Even though the thickness of the device has been further optimized and the internal cooling structure has become more precise, the repairability of Samsung Galaxy S26 Ultra has not been compromised. In the scoring system of the well-known disassembly review agency PBKreviews, it still received a high score of 9/10, the same as the previous generation Galaxy S25 Ultra, balancing extreme performance with convenient later maintenance.

During daily use, whether it is running large-scale mobile games for a long time, recording 4K high-definition videos, or continuously performing high-load computing, the core chip of the phone will generate a large amount of heat. This thin as a cicada's wing graphite heat sink is always working silently inside the device, quickly dispersing local high temperatures and evenly spreading heat, fundamentally avoiding performance reduction, game lag, and touch control delay caused by overheating of the device. It is these hidden details of optimization inside the device, which are difficult to be seen with the naked eye, that have enabled Samsung Galaxy S26 Ultra to achieve a balance between extreme performance and lightweight grip. Behind this, there is no doubt that it is thanks to enterprises like Jiangxi Dasen Technology, which focus on material innovation, using cutting-edge cooling technology, to lay a solid foundation for each iteration and upgrade of smartphones.