Electronic equipment

Abstract

The invention relates to the technical field of heat dissipation equipment, in particular to electronic equipment which comprises a heating device, a first heat dissipation module and a second heat dissipation module. Wherein the first heat dissipation module transfers heat through phase change and / or fluid flow, and the second heat dissipation module transfers heat through phonons and / or electrons; in the first direction, the second heat dissipation module is arranged between the first heat dissipation module and the heating device, the first heat dissipation module is attached to the second heat dissipation module, the projection of the heating device and the projection of the second heat dissipation module partially or completely coincide, and the projection of the first heat dissipation module and the projection of the second heat dissipation module partially or completely coincide. The projection of the first heat dissipation module and the projection of the heating device are partially overlapped. According to the electronic equipment provided by the invention, the problems of short-time overheating, local drying-out and overheating impact caused by a high impedance state when the first heat dissipation module works are effectively solved, and the low thermal performance of the system when the first heat dissipation module cannot work is ensured.

Description

[0001] This application claims the priority of the Chinese patent application filed with the China Patent Office on August 29, 2023, with application number 202311103369.0 and application name “An Electronic Device”, all contents of which are incorporated by reference in this application. Technical Field

[0002] The present application relates to the technical field of heat dissipation equipment, and in particular to an electronic device. Background Art

[0003] Thermal management of mobile terminals has not only become one of the important bottlenecks for improving the performance and reliability of mobile terminals and equipment, but also one of the indicators that consumers pay the most attention to. Taking mobile phones as an example, they have undergone several generations of hardware cooling technology evolution, including a variety of cooling systems, such as local thermal interface materials, graphite heat dissipation materials and heat sinks.

[0004] However, in actual application, the application scenarios of mobile terminals are ever-changing. The above-mentioned heat dissipation system (such as a heat spreader) is affected by factors such as the heat transfer starting temperature, time, heat source position, and external force field. In different usage scenarios (such as changes in the heat source position, low temperature start-up, start-up lag or failure to start, sudden acceleration, deceleration or rotation, etc.), the system may fail or fail to operate normally, which limits the performance of the mobile terminal and affects the user's thermal experience. Summary of the invention

[0005] The present application provides an electronic device that can solve the problems of heat source position change, low temperature startup, startup lag or inability to start, sudden acceleration, deceleration or rotation, and local damage to the heat dissipation module in different application scenarios. The present application is introduced from multiple aspects below, and the implementation methods and beneficial effects of the following multiple aspects can be referenced to each other.

[0006] In a first aspect, the present application provides an electronic device, comprising: a heating device (e.g., a SOC), a first heat dissipation module, and a second heat dissipation module; wherein the first heat dissipation module transfers heat through phase change and / or fluid flow, and the second heat dissipation module transfers heat through phonons and / or electrons; along a first direction, the second heat dissipation module is arranged between the first heat dissipation module and the heating device, the first heat dissipation module is attached to the second heat dissipation module, the projection of the heating device and the projection of the second heat dissipation module partially or completely overlap, the projection of the first heat dissipation module and the projection of the second heat dissipation module partially or completely overlap, and the projection of the first heat dissipation module and the projection of the heating device partially overlap.

[0007] In some possible implementations, those skilled in the art believe that placing the first heat dissipation module between the heating device and the second heat dissipation module has a better heat dissipation effect. The embodiment of the present application is not arranged in this way. The embodiment of the present application creatively adopts the arrangement of the second heat dissipation module between the heating device and the first heat dissipation module. That is, the heat on the heating device is first evenly distributed through the second heat dissipation module, and then dissipated through the first heat dissipation module, so that the combined heat dissipation of the first heat dissipation module and the second heat dissipation module in the embodiment of the present application can achieve better thermal performance. That is, the order of heat dissipation in the embodiment of the present application is changed.

[0008] The second heat dissipation module of the embodiment of the present application relies on phonons and / or electrons between molecules, atoms, and lattices to transfer heat, and there is no hysteresis in the startup temperature and startup time, and the heat transfer is independent of the location and change of the heat source and the external force field. In some possible implementations, due to the spatial structure of the electronic device, when the heating device is located at the edge of the first heat dissipation module, or there are multiple heating devices, that is, when the projection of the first heat dissipation module and the heating device along the first direction partially overlap, the embodiment of the present application can first average the heat of the heating device through the second heat dissipation module, and then transfer it to the first heat dissipation module. Therefore, combining the second heat dissipation module with the first heat dissipation module ensures the system's bottom-line thermal performance when the first heat dissipation module cannot work, effectively solves the high impedance state when the first heat dissipation module is working, and avoids the problems of short-term overheating, local drying and overheating shock.

[0009] In a possible implementation of the first aspect above, the first heat dissipation module includes any one of a heat spreader, a heat pipe, a loop heat pipe and a liquid cooling module.

[0010] In a possible implementation of the first aspect above, the second heat dissipation module includes a hexagonal ring structure material layer.

[0011] In a possible implementation of the first aspect above, the second heat dissipation module includes a composite material layer, and the composite material layer includes a hexagonal ring structure material layer and a non-hexagonal ring structure material layer.

[0012] In a possible implementation of the first aspect above, the hexagonal ring structure material layer includes a graphene film, an artificial graphite sheet, and a boron nitride film.

[0013] In a possible implementation of the first aspect above, the composite material layer includes any one of a phase change material and a heat storage material.

[0014] In a possible implementation of the first aspect above, it also includes a middle frame, the first heat dissipation module includes a heat spreader, and the second heat dissipation module includes a graphene film; the heating device is arranged in the middle frame, and the graphene film is attached to a side of the heat spreader facing the heating device, and along the first direction, the projection of the graphene film covers the projection of the heating device.

[0015] In a possible implementation of the first aspect above, the electronic device includes a first middle frame, a second middle frame and a rotating shaft, the first middle frame and the second middle frame are rotatably connected by the rotating shaft to switch between a folded position and an unfolded position; the first heat dissipation module includes a liquid cooling module, the liquid cooling module includes a pump and a liquid cooling film member that are connected, the liquid cooling film member is used to supply a cooling medium to flow, and the pump is used to provide power for the flow of the cooling medium in the liquid cooling film member; the liquid cooling film member includes a first part, a second part, and a bendable area connecting the first part and the second part, the first part of the liquid cooling film member is arranged in the first middle frame, the second part of the liquid cooling film member is arranged in the second middle frame, and the bendable area of ​​the liquid cooling film member passes through or crosses the rotating shaft; the second heat dissipation module includes a graphene film; at least the first middle frame is provided with a heating device, the graphene film is attached to the side of the first part of the liquid cooling film member facing the heating device, and along the first direction, the projection of the graphene film covers the projection of the heating device.

[0016] In a possible implementation of the first aspect above, the projection of the graphene film covers the projection of the first part, the projection of the second part, and the projection of the bendable area of ​​the liquid-cooled film.

[0017] In a possible implementation of the first aspect above, the graphene film includes a first part, a second part, and a bendable area connecting the first part and the second part of the graphene film; the first part of the graphene film is attached to the side of the first part of the liquid-cooling film facing the heating device, and along the first direction, the projection of the first part of the graphene film covers the projection of the heating device; the second part of the graphene film is arranged in the second middle frame, and the bendable area of ​​the graphene film passes through or crosses the rotating axis.

[0018] In a possible implementation of the first aspect above, the electronic device includes a first middle frame, a second middle frame and a hinge, the first middle frame and the second middle frame are rotatably connected by the hinge so as to switch between a folded position and an unfolded position; the first heat dissipation module includes a heat spreader; the second heat dissipation module includes a graphene film, the graphene film includes a first part, a second part, and a bendable area connecting the first part and the second part of the graphene film; the heating device and the heat spreader are arranged in the first middle frame, the first part of the graphene film is attached to a side of the heat spreader facing the heating device, along the first direction, the projection of the first part of the graphene film covers the projection of the heating device, the second part of the graphene film is arranged in the second middle frame, and the bendable area of ​​the graphene film passes through or crosses the hinge.

[0019] In a possible implementation of the first aspect above, the electronic device includes a first middle frame, a second middle frame and a hinge, the first middle frame and the second middle frame are rotatably connected by the hinge so as to switch between a folded position and an unfolded position; the first heat dissipation module includes a heat spreader; the second heat dissipation module includes a graphene film, the graphene film includes a first part, a second part, and a bendable area connecting the first part and the second part of the graphene film; the heating device and the heat spreader are arranged in the first middle frame, the first part of the graphene film is attached to a side of the heat spreader facing the heating device, along the first direction, the projection of the first part of the graphene film covers the projection of the heating device, the second part of the graphene film is arranged in the second middle frame, and the bendable area of ​​the graphene film passes through or crosses the hinge.

[0020] In a possible implementation of the first aspect, the surface and interior of the hexagonal ring structure material layer have a plurality of wrinkle structures, and the 1 μm 2 The total length of the wrinkle structure per unit area is in the range of 1 μm to 500 μm, the multiple wrinkle structures include multiple micro wrinkle structures with micron or submicron lengths, and the multiple micro wrinkle structures are irregularly distributed on the surface of the second heat dissipation module.

[0021] In a possible implementation of the first aspect above, a shielding cover and / or a thermal interface material is provided between the heat generating device and the second heat dissipation module.

[0022] In a possible implementation of the first aspect above, the surface of the second heat dissipation module that is in contact with the heating device is a planar structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 (a) and (b) show the different heat source positions and thermal performance changes of the heat sink;

[0024] Figure 2 The low temperature startup high impedance characteristics of the two-phase vapor chamber heat dissipation module are shown, wherein the solid line and the dotted line represent different heat source temperatures;

[0025] Figure 3 The variable impedance characteristics and temperature difference of the pump cooling module are shown;

[0026] Figure 4 The capillary driving force required for the vapor chamber in different scenarios is shown;

[0027] Figure 5 (a) and (b) show schematic diagrams of local damage during transportation, installation and use of the cooling system;

[0028] Figure 6 A logic diagram of an active cooling control system showing another technique;

[0029] Figure 7A schematic diagram of an active liquid cooling system showing another technique;

[0030] Figure 8 A schematic diagram showing a combination of a first heat dissipation module and a second heat dissipation module is shown;

[0031] Fig. 9 A schematic diagram of a structural decomposition of an electronic device according to the first embodiment is shown, comprising a first heat dissipation module and a heating device;

[0032] Fig.10 Another structural decomposition schematic diagram of the electronic device of the first embodiment is shown, including a first heat dissipation module, a second heat dissipation module and a heating device;

[0033] Fig.11 A schematic structural diagram of an electronic device of Embodiment 2 is shown, comprising a first heat dissipation module and a heating device;

[0034] Fig.12 Another structural schematic diagram of the electronic device of the second embodiment is shown, comprising a first heat dissipation module, a second heat dissipation module and a heating device;

[0035] Fig.13 A schematic structural diagram of an electronic device of Embodiment 3 is shown, comprising a first heat dissipation module, a second heat dissipation module and a heating device;

[0036] Fig.14 A schematic structural diagram of an electronic device of Embodiment 4 is shown, comprising a first heat dissipation module, a second heat dissipation module and a heating device, wherein the first heat dissipation module is a liquid cooling module;

[0037] Fig.15 Another structural schematic diagram of an electronic device of the fourth embodiment is shown, comprising a first heat dissipation module, a second heat dissipation module and a heating device, wherein the first heat dissipation module is a heat sink;

[0038] Fig.16 A three-dimensional diagram of an electronic device under a viewing angle is shown, comprising a first heat dissipation module, a second heat dissipation module and a heating device, wherein the first heat dissipation module is a liquid cooling module;

[0039] Fig.17 A three-dimensional diagram of an electronic device from another perspective is shown, comprising a first heat dissipation module, a second heat dissipation module and a heating device, wherein the first heat dissipation module is a liquid cooling module;

[0040] Fig.18 (a), (b) and (c) show the internal microstructure of the second heat dissipation module, wherein: Fig.18 (c) is Fig.18 A magnified partial view of (b). DETAILED DESCRIPTION

[0041] The embodiment of the present application provides a high-impedance state heat dissipation compensation solution for a variable impedance heat dissipation module.

[0042] The electronic device of the embodiment of the present application includes a first heat dissipation module and a second heat dissipation module. The first heat dissipation module mainly relies on phase change and / or fluid flow to transfer heat. Heat transfer has a start-up temperature and start-up time requirement, which is related to the location and change of the heat source. The pipeline and flow can be affected by the external force field, so that the heat conduction is affected by the external force field.

[0043] The second heat dissipation module relies on phonons and / or electrons between molecules, atoms, and lattices to transfer heat. Exemplarily, the second heat dissipation module is a hexagonal ring structure material layer, each hexagonal ring structure is connected by a covalent bond, and the surface and interior of the material have multiple microscopic wrinkled structures to achieve flexibility and bendability. Under daily application temperature and pressure, there is no start-up temperature and start-up time lag, and heat transfer is independent of the position and change of the heat source and the external force field.

[0044] The second heat dissipation module is laid between the first heat dissipation module and the heating device of the electronic device. After the heating device generates heat, it is first evenly heated by the second heat dissipation module and then dissipated by the first heat dissipation module. Since the second heat dissipation module is not affected by factors such as daily application temperature, pressure, startup temperature, startup time lag, heat transfer and heat source position and changes, external force field, etc., or the impact is small, it effectively solves the high impedance state that may occur during the operation of the first heat dissipation module, avoids short-term, local drying, overheating shock, or the system's guaranteed thermal performance when the first heat dissipation module cannot work, and is suitable for mobile terminals, vehicle-mounted and other mobile electronic devices.

[0045] refer to Figures 1 to 5 The following embodiments of the present application illustrate the problems that may affect the heat dissipation performance of the first heat dissipation module in different usage scenarios.

[0046] (1) Heat source location and changes

[0047] refer to Figure 1 (a) and (b) in Table 1, Figure 1 (a) and (b) show the different heat source positions and thermal performance changes of the vapor chamber, and Table 1 shows the performance differences of the same vapor chamber at different heat source positions. Figure 1 104 shown in (b) represents a cable for heating the test point.

[0048] Table 1: Performance differences of the same VC at different heat source locations

[0049]

[0050] like Figure 1As shown in (a) and (b) and Table 1, when the heat source is at position 101 at the top edge of the vapor chamber (VC), the temperature difference between the cold (test point 103) and the hot (test point 101) is 12.328°C. However, when the heat source is at position 103 at the bottom center of the vapor chamber, the temperature difference between the cold (test point 102) and the hot (test point 103) is only 2.861°C.

[0051] It can be seen that the gas-liquid flow resistance of the two-phase heat dissipation device is strongly related to the channel size (such as height, width or length, etc.), that is, the heat dissipation performance of the first heat dissipation module is affected by the location and change of the heat source. Figure 1 The width of the heat sink (shown as 101, 102 and 103 in FIG. 101 ) determines the size of the operating pressure. That is, the width of the top edge position 101 is narrower and the width of the bottom center position 103 is larger. Then, when the heat source is at the bottom center position 103, the temperature equalization effect is better than when the heat source is at the top edge position 101. Exemplarily, when the heat source is at the bottom center position 103, the equivalent thermal conductivity of the heat sink is >8000W / mK.

[0052] (2) Low temperature start:

[0053] refer to Figure 2 , Figure 2 The low temperature startup high impedance characteristics of the two-phase heat sink module are shown ( Figure 2 The solid line indicates that the heat source temperature is 55-65°C; the dotted line indicates that the heat source temperature is 35-45°C).

[0054] For two-phase natural heat dissipation self-driving devices such as heat pipes (HP), loop heat pipes (LHP), and vapor chambers (VC), the temperature difference is the starting condition and there is a starting temperature requirement. For example, Figure 2 As shown in the figure, when the heat spreader is used to even out the temperature on the surface of a mobile phone and to carry medium and light loads, the operating temperature of the heat spreader is between 35-45°C (as shown in the figure). Figure 2 The temperature is low, the vapor chamber is in a high impedance state, the temperature difference between the hot and cold ends is large, and the heat dissipation performance of the vapor chamber is not fully utilized; when the operating temperature of the vapor chamber is between 55-65°C (as shown in the dashed line), the temperature is low, the vapor chamber is in a high impedance state, the temperature difference between the hot and cold ends is large, and the heat dissipation performance of the vapor chamber is not fully utilized; when the operating temperature of the vapor chamber is between 5 Figure 2 As shown in the implementation of FIG), the thermal performance of the heat spreader is better. It can be seen that the heat dissipation performance of the first heat dissipation module is affected by the startup temperature.

[0055] (3) Startup delay or failure to start

[0056] refer to Figure 3 , Figure 3 The variable impedance characteristics and temperature difference of the pump cooling module are shown. Figure 3(a) is a liquid cooling system mockup, (b) is the temperature difference when the pump is not started, and (c) is the temperature difference after the pump is started).

[0057] For a passive liquid cooling system (such as a vapor chamber), startup lag may occur, especially under sudden high load (Boost) and high chip impedance of the chip (System on Chip, SOC).

[0058] For active liquid cooling systems, the pump is turned on and off based on the overheating report of the temperature sensor, and it is also impossible to fully synchronize the temperature changes of the chip SOC and the charging chip. In actual application, for energy saving or noise reduction purposes, the pump of the active liquid cooling system is not started under medium and light loads, and it is necessary to rely on pure natural heat dissipation to meet most user application scenarios, thereby extending the life of the liquid cooling system. Figure 3 As shown in (b), when the pump is not started, the temperature difference between the hot and cold ends is large, relying only on pure natural heat dissipation. Figure 3 As shown in (c), when the pump is turned on, the temperature difference between the hot and cold ends is small.

[0059] It can be seen from this that the first heat dissipation module may have a startup lag or fail to start in different application scenarios, thereby affecting the heat dissipation performance.

[0060] (4) Variable acceleration

[0061] refer to Figure 4 , Figure 4 The capillary driving force required for the vapor chamber in different scenarios is shown. Figure 4 (a) is the scenario of favorable gravity, (b) is the scenario of adverse gravity, and (c) is the scenario of non-inertial force, such as rotational centrifugal force and tidal force). ΔPi represents the tidal force pressure drop.

[0062] The ultra-high thermal conductivity of two-phase heat transfer depends on the release and absorption of latent heat of evaporation and condensation phase changes. It is necessary to reach a certain operating temperature so that the capillary force (that is, the capillary driving force ΔPca depends on inherent parameters such as the surface tension of the working fluid, the effective radius of multiple capillary structures, and the hydrophilicity of the solid material surface) can overcome the influence of gas-liquid resistance and gravity to achieve normal circulation of the vapor-liquid phase.

[0063] like Figure 4 As shown in (a), (b) and (c), the capillary driving force required for the vapor chamber in different scenarios is different. In sudden acceleration, deceleration, and rotation scenarios, the capillary force may not be able to overcome the additional acceleration resistance or rotational centrifugal force, causing the vapor chamber to be in a high impedance state or even unable to operate. For mobile terminals, in-vehicle devices, and other devices that often experience sudden acceleration, deceleration, and turning, design avoidance is required to prevent system failure and crash.

[0064] In addition, for a pump-driven liquid cooling system (such as a liquid cooling module), the pump driving force also needs to overcome the additional resistance generated by the variable acceleration, which causes the pump-driven liquid cooling system to be in a relatively high impedance state. It can be seen that the first heat dissipation module will be in a high impedance state in different application scenarios due to the generation of variable acceleration.

[0065] (5) Partial damage to the heat dissipation module

[0066] refer to Figure 5 In (a) and (b), Figure 5 A schematic diagram showing the local damage of the cooling system during transportation, installation and use (where Figure 5 (a) shows the defect T (shown as the hollow circle in the figure). Figure 5 (b) shows test points 101, 102 and 103), and Table 2 shows the performance difference after the same heat spreader is locally damaged.

[0067] Table 2: Performance differences after local damage to the same VC

[0068]

[0069] like Figure 5 As shown in (a) and (b) and Table 2, local damage to the heat spreader during transportation, installation, and use will narrow the liquid and gas channels in the heat spreader, sharply increase the local resistance to the flow of liquid and gas, and reduce the heat dissipation performance. The reason is that the cover plate used in the heat spreader undergoes irreversible plastic deformation, resulting in damage to the capillary or steam channels, a huge drop in local thermal conductivity, and possible local hot spots. It can be seen that the heat dissipation performance of the first heat dissipation module in different application scenarios will be affected by the local damage to the heat dissipation module.

[0070] Table 3: Common working fluids and performance differences of two-phase cooling modules

[0071] physical properties water Liquid Ammonia Methanol Melting point(℃) 0 -77.7 -97.8 Boiling point(℃) 100 -33.4 64.7 100℃ saturated vapor pressure (Mpa) 0.1 0.45 0.4 Relative density (g / cm3) 1 0.6 0.79 Viscosity (mPa·s) 0.89 0.26 0.55 Latent heat of vaporization (kJ / kg) 2260 1055 1109

[0072] For two-phase heat dissipation systems such as heat spreaders / heat pipes / loop heat pipes, the commonly used working fluid is deionized pure water. Referring to Table 3, in some possible implementations, a technology can change the working fluid to lower the startup temperature. For example, as shown in Table 3, when the water working fluid in the two-phase heat dissipation system is replaced with liquid ammonia, methanol, etc., the startup temperature of the heat dissipation system is greatly reduced, which is suitable for surface temperature equalization scenarios other than chip cooling.

[0073] However, the above technology has the problem of high saturated vapor pressure of the working fluid at 100°C. In some possible usage scenarios, when the operating temperature of the electronic product is 100°C, the saturated vapor pressure of liquid ammonia reaches 4.5 atmospheres, and the saturated vapor pressure of methanol reaches 4 atmospheres.

[0074] Therefore, using liquid ammonia and methanol as working fluids is not suitable for the cooling systems of ultra-thin systems such as current mobile phones. It will cause obvious malfunctions in ultra-thin systems such as mobile phones, affect battery safety and screen reliability, and is not suitable for scenarios where terminal consumer electronics are in close contact with users.

[0075] In addition, the above-mentioned technology also has the problem of low latent heat of vaporization of the working fluid. As shown in Table 3, the latent heat of vaporization of liquid ammonia, methanol, etc. is less than 50% of the latent heat of vaporization of water. This results in that a two-phase heat dissipation system using liquid ammonia and methanol as working fluids requires a larger injection volume and a larger volume to achieve the same amount of heat absorbed and released by a two-phase heat dissipation system using water as the working fluid, which is not suitable for compact products such as terminals.

[0076] In some possible implementations, reference Figure 6 and Figure 7 ,Another technology is an intelligently deployed active heat dissipation control system solution, ,which includes a detection module (such as scene condition detection, ,temperature condition detection), a control module (such as CPU, pump driver board, MCU), ,and an execution module (such as pumps, gas-liquid pipelines, valves, ,etc.).

[0077] Figure 6 A logic diagram of an active cooling control system showing another technique, Figure 7 Another active liquid cooling system is shown, which is based on scene recognition, power consumption monitoring and predictive temperature control. It is a system for starting the liquid cooling system in advance before the device heats up.

[0078] like Figure 6 As shown, the control module of the liquid cooling system will perform logical judgment on the scene conditions (such as the device is in a game or charging scene state) or temperature conditions (such as temperature 1 reaches 45°C and temperature 2 reaches 38°C), thereby outputting the working state to be executed by the execution module to match the heat dissipation requirements of the device (such as a heat-generating device).

[0079] However, the other technology mentioned above has the problems of complex system, high cost, difficulty in identifying sudden acceleration, deceleration, centrifugal force and other application scenarios, and high probability of misjudgment.

[0080] To solve the above problems, refer to Figure 8 An embodiment of the present application provides an electronic device, including: a heating device 20, a first heat dissipation module 30 and a second heat dissipation module 40. Figure 8 A schematic diagram of a combination of a first heat dissipation module 30 (eg, a heat spreader with a thickness of 0.4 mm) and a second heat dissipation module 40 (eg, a graphene plate with a thickness of 0.4 mm) is shown.

[0081] The first heat dissipation module 30 mainly includes heat transfer by phase change and / or molecular flow, usually a heat pipe (HP), a loop heat pipe (LHP), a vapor chamber (VC) type two-phase heat dissipation device, powered by capillary force, or a single-phase two-phase active liquid cooling system powered by a pump 302. Exemplarily, the equivalent thermal conductivity of the first heat dissipation module 30 is ≥5000W / mK, and has a heat dissipation capacity far higher than that of phonon and electronic thermal conductivity (i.e., the second heat dissipation module 40), but the heat transfer of the first heat dissipation module 30 has a startup temperature and startup time, which is related to the location and change of the heat source and is affected by the external force field.

[0082] The second heat dissipation module 40 is a hexagonal ring structure material layer, each hexagonal ring structure is connected by a covalent bond and can be bent. Heat transfer is carried out by phonons and / or electrons between molecules, atoms, and lattices. It can be understood by those skilled in the art that under the temperature and pressure of daily application, since the movement speed of phonons and electrons of atoms, molecules or lattices is much higher than the speed that can be achieved by the human body and electronic equipment, there is no hysteresis in the startup temperature and startup time, and heat transfer is independent of the position and change of the heat source and the external force field.

[0083] In some possible implementations, such as Figure 8 As shown in FIG. 1 , the surface where the second heat dissipation module 40 and the heating device 20 are attached to each other in the embodiment of the present application is a planar structure.

[0084] That is, the first heat dissipation module 30 transfers heat through phase change and / or fluid flow, and the second heat dissipation module 40 transfers heat through phonons and / or electrons.

[0085] The electronic devices to which the heat dissipation module of the embodiment of the present application is applied include, for example, mobile phones, foldable mobile phones, headphones, tablet computers, personal digital assistants (PDAs), laptop computers, wearable devices (such as smart watches), car computers, portable multimedia players, navigation devices, desktop computers, televisions, and any other devices that require heat dissipation. The embodiment of the present application does not impose any special restrictions on the specific form of the above-mentioned electronic devices. For the convenience of explanation, the following description is made by taking the electronic device as an example of a mobile phone.

[0086] Exemplarily, the heat generating devices include, but are not limited to, camera modules, sensors, system on chip (SOC), charging modules (Charge IC), batteries, system in package (SIP) modules, speaker modules, circuit board assemblies, etc. The number of heat generating devices is not limited.

[0087] Continue to refer Figure 8In combination with Table 4 and Table 5, Table 4 shows the comparison of temperature difference (°C) of different heat dissipation schemes at different heat source positions, and Table 5 shows the comparison of equivalent thermal conductivity (W / mK) of different heat dissipation schemes at different heat source positions.

[0088] Table 4: Comparison of temperature difference (°C) of different heat dissipation solutions at different heat source locations (test conditions: Figure 8 )

[0089]

[0090] Table 5: Comparison of equivalent thermal conductivity (W / mK) of different heat dissipation solutions at different heat source locations

[0091]

[0092] When the electronic cooling system only uses the first cooling module 30, that is, Fig. 9 As shown in , the temperature difference and equivalent thermal conductivity are strongly correlated with the heat source position, reaching a maximum of 11.2°C, and the equivalent thermal conductivity fluctuation is >6000W / mK. When only the second heat dissipation module 40 is used, although the thermal conductivity remains constant at 1350W / mK, the temperature equalization capability is limited, with a minimum temperature difference of 5.3°C, which cannot meet the heat dissipation requirements under high load.

[0093] After the second heat dissipation module 40 is laid between the first heat dissipation module 30 and the heating element 20, the first heat dissipation module 30 and the second heat dissipation module 40 are attached to each other. Fig.10 As shown in , along the first direction, the second heat dissipation module 40 is arranged between the first heat dissipation module 30 and the heating device 20, and the first heat dissipation module 30 is attached to the second heat dissipation module 40. It can be found that the correlation with the heat source position is greatly reduced, and the equivalent thermal conductivity fluctuates between 7200 and 8100 W / mK, which meets the heat dissipation requirements of the system for stable operation.

[0094] refer to Figures 11 to 17 , a projection of a heating device 20 (shown on the right side of the figure, such as SOC) (as shown in FIG. Fig.12 The projection of the second heat dissipation module 40 (shown in the dashed box 20) Fig.12 The projection of the first heat dissipation module 30 and the projection of the second heat dissipation module 40 all overlap, and the projection of the first heat dissipation module 30 and the projection of one of the heat dissipation devices 20 (shown on the right side of the figure) all overlap, and the projection of the first heat dissipation module 30 and the projection of another heat dissipation device 20 (shown on the left side of the figure) partially overlap. In some possible implementations, the projection of the first heat dissipation module 30 partially overlaps with the projection of the second heat dissipation module 40.

[0095] The first heat dissipation module 30 is provided on the heating device 20 of the electronic product, and the two are partially or completely overlapped. The second heat dissipation module 40 is provided between the first heat dissipation module 30 and the main heat source, and the three are partially or completely overlapped. A shielding cover, a shielding cover, etc. can be provided between the heating device 20 and the first heat dissipation module 30 and the second heat dissipation module 40 according to the shielding requirements. In order to reduce the contact thermal resistance between solids, a thermal interface material (such as Figure 8 As shown). For example, refer to Fig.10 The electronic device of the embodiment of the present application further includes a screen 50 and a battery 60, along a first direction (such as Fig.10 A first heat dissipation module 30, a second heat dissipation module 40, a heating device 20 and a battery 60 are sequentially disposed between the screen 50 and the middle frame 10 (as shown in the X direction).

[0096] In summary, unlike some possible implementations in which the first heat dissipation module 30 is disposed between the heating device 20 and the second heat dissipation module 40, the embodiment of the present application creatively adopts the arrangement of the second heat dissipation module 40 between the heating device 20 and the first heat dissipation module 30. That is, the heat on the heating device 20 is firstly evenly distributed through the second heat dissipation module 40, and then dissipated through the first heat dissipation module 30, so that the combined heat dissipation of the first heat dissipation module 30 and the second heat dissipation module 40 in the embodiment of the present application can achieve better thermal performance.

[0097] The second heat dissipation module 40 relies on phonons and / or electrons between molecules, atoms, and lattices to transfer heat, and there is no hysteresis in the startup temperature and startup time, and the heat transfer is independent of the location and change of the heat source and the external force field. Therefore, the second heat dissipation module 40 is structured in phase with the first heat dissipation module 30 to ensure the system's minimum thermal performance when the first heat dissipation module 30 cannot work, effectively solving the high impedance state when the first heat dissipation module 30 is working, and avoiding the problems of short-term overheating, local drying out, and overheating shock.

[0098] Exemplarily, the first heat dissipation module 30 includes any one of a heat spreader, a heat pipe, a loop heat pipe and a liquid cooling module.

[0099] The specific structure of the heat dissipation module is described in detail below with reference to the accompanying drawings.

[0100] Embodiment 1

[0101] In some possible implementations, reference Fig. 9 and Fig.10 The embodiment of the present application provides an electronic device, which further includes a middle frame 10, a first heat dissipation module 30 including a heat spreader, and a second heat dissipation module 40 including a graphene film. The heating device 20 is arranged in the middle frame 10, and the graphene film (i.e., the second heat dissipation module 40) is attached to a side of the heat spreader facing the heating device 20 (e.g., SOC), and the graphene film is arranged along a first direction (e.g., Fig.10The projection of the graphene film covers the projection of the heating device 20 .

[0102] Fig. 9 and Fig.10 A high impedance compensation heat dissipation solution for a straight-panel computer is shown. Table 5 shows the thermal gain (Q=3.5W) of the composite heat dissipation module for a straight-panel computer according to an embodiment of the present application, where Q represents the heat generated by the heat generating device 20 .

[0103] Table 5 Thermal gain of the composite heat dissipation module of the straight-screen computer of the present application embodiment (Q=3.5W)

[0104] Module temperature difference (℃) Screen side difference (℃) Equivalent thermal conductivity (W / mK) 1. The first heat dissipation module 4.1 5.8 4210 2. Second heat dissipation module 7.8 9.6 1548 3. Composite heat dissipation module 2.1 3.5 8220

[0105] Specifically, the first heat dissipation module 30 takes a heat spreader as an example, uses water as a working medium, absorbs heat into water vapor in the evaporation area (heat generating device 20 on the printed circuit board (PCB), i.e., chip SOC), and liquefies into liquid water in the condensation area (battery area), and relies on the capillary force in the heat spreader to drive the liquid water back to the vicinity of the heat generating device. The second heat dissipation module 40 takes a graphene film as an example, and illustratively, the thickness of the graphene film is 0.006 mm.

[0106] like Fig. 9 As shown in the figure, the original design only uses a large area of ​​0.3mm thick ultra-thin UTVC (i.e., heat spreader), and the heating device 20 is arranged at the edge of the UTVC. Since there is an ineffective skirt of about 2mm around the UTVC, the heating device 20 cannot be completely covered. As a result, even if the heat spreader unit can achieve ⊿Tmax≤4.1℃, the heat dissipation effect on the screen side is still poor, and the temperature difference between the cold and hot ends is about 5.8℃.

[0107] like Fig.10 As shown, after adopting the improved scheme of the embodiment of the present application, the second heat dissipation module 40 fully covers the heat source, and the heat of the SOC (i.e., the heat generating device 20) is conducted to the 0.06mm graphene film with high thermal conductivity (equivalent thermal conductivity coefficient ≥ 1000W / mK) through the TIM material (i.e., thermal interface material) and the shielding cover, and then transferred to the heat spreader.

[0108] That is, the second heat dissipation module 40 is disposed between the first heat dissipation module 30 and the main heat source, the three are partially or completely overlapped, and the second heat dissipation module 40 completely covers the main heat source (ie, the heat generating device 20).

[0109] It should be noted that the embodiment of the present application does not impose any specific restrictions on the projection positions of the heating device 20, the first heat dissipation module 30, and the second heat dissipation module 40. That is, along the first direction, the projection of the heating device 20 and the projection of the second heat dissipation module 40 may partially or completely overlap, the projection of the first heat dissipation module 30 and the projection of the second heat dissipation module 40 may partially or completely overlap, and the projection of the first heat dissipation module 30 and the projection of the heating device 20 may partially or completely overlap.

[0110] Compared with the original design, using the same first heat dissipation module 30 (i.e. the above-mentioned heat spreader, UTVC), the combined heat dissipation module (i.e., the first heat dissipation module 30 combined with the second heat dissipation module 40) provided in the embodiment of the present application has a single thermal performance of ⊿Tmax≤2.1°C, an average temperature on the screen side≤3.5°C, and an equivalent thermal conductivity coefficient increased by about 50%.

[0111] In summary, the improved scheme of the embodiment of the present application, on the one hand, when using the same heat spreader (i.e., the first heat dissipation module 30), the equivalent thermal conductivity is increased by about 50%, and the correlation between the heat spreader capacity and the heat source position is reduced by 50%. On the other hand, the improved scheme of the embodiment of the present application simplifies the design of the heat spreader, avoiding 2.5D or complex-shaped heat spreaders, which lead to complex processes, reduced yields, and increased costs.

[0112] Embodiment 2

[0113] In some possible implementations, reference Fig.11 and Fig.12 The present application provides an electronic device, which includes a first middle frame 11, a second middle frame 12 and a rotating shaft (not shown in the figure), wherein the first middle frame 11 and the second middle frame 12 are rotatably connected by the rotating shaft to be able to be in a folded position and an unfolded position (such as Fig.12 That is, the mobile phone in the embodiment of the present application is a folding mobile phone. The following embodiment of the present application is illustrated by taking a folding mobile phone as an example.

[0114] Fig.11 and Fig.12 A high impedance compensation heat dissipation solution for a folding machine is shown, and Table 6 shows the liquid cooling heat gain (Q=3.5W) of the folding machine according to an embodiment of the present application.

[0115] Table 6 Liquid cooling heat gain of folding machine in the present embodiment (Q=3.5W)

[0116] Single temperature difference Temperature difference between upper and lower screens Equivalent thermal conductivity 1. The first heat dissipation module 4.2 6.7 4138 2. Second heat dissipation module 6.9 13.8 1795 3. Composite heat dissipation module 3.1 4.8 5606

[0117] Specifically, the liquid cooling module includes a connected pump 302 and a liquid cooling film 301, the pump 302 is used to provide power for the flow of the cooling medium in the liquid cooling film 301, and the liquid cooling film 301 is used to flow the cooling medium so that the cooling medium (i.e., the working fluid) circulates between the cold and hot sources and the upper and lower screens (i.e., the first middle frame 11 and the second middle frame 12). Exemplarily, the liquid cooling module uses water as the working fluid, but is not limited thereto, and can also be other working fluids or composite working fluids such as fluorinated liquid and thermal conductive silicone oil, and nano solid particles can be added to the working fluid to enhance thermal performance.

[0118] The liquid-cooled film 301 includes a first portion 3011, a second portion 3012, and a bendable area 3013 connecting the first portion 3011 and the second portion 3012. The first portion 3011 of the liquid-cooled film 301 is disposed in the first middle frame 11, the second portion 3012 of the liquid-cooled film 301 is disposed in the second middle frame 12, and the bendable area 3013 of the liquid-cooled film 301 passes through or crosses the rotating shaft. The second heat dissipation module 40 includes a graphene film. It should be noted that the above-mentioned bendable area 3013 passing through the rotating shaft means that there is a through hole in the rotating shaft for the bendable area 3013 to pass through, and the above-mentioned bendable area 3013 crossing the rotating shaft means that the bendable area 3013 crosses the rotating shaft 13 (such as from one side surface of the rotating shaft) from the rotating shaft. Fig.16 ), so that the bendable area 3013 connects the second part 3011 located in the first middle frame 11 and the second part 3012 located in the second middle frame 12.

[0119] At least the first middle frame 11 is provided with a heating device 20 , and the graphene film is attached to a side of the first portion 3011 of the liquid-cooling film 301 facing the heating device 20 , and along the first direction, the projection of the graphene film covers the projection of the heating device 20 .

[0120] like Fig.11 As shown, the original design only uses a large-area liquid cooling film (i.e., the first heat dissipation module 30). For example, the thickness of the large-area liquid cooling film is 0.2 mm, which is a non-metallic liquid cooling film with a thermal conductivity of 0.2 W / mK. The heating device 20 is arranged on the liquid cooling passage (i.e., the liquid cooling film 301). Since there is a 2 mm ineffective skirt around the liquid cooling module and it is a non-metallic liquid cooling film, the thermal conductivity of the liquid cooling film body is relatively small, resulting in that during the application of the actual product, even if the monomer of the liquid cooling module is uniformly heated ⊿Tmax≤3.6°C, the cross-axis heat transfer capacity of the liquid cooling module is weak, the temperature difference between the hot and cold ends is large, which is 6°C, and the heat dissipation performance is relatively weak.

[0121] like Fig.12As shown, the scheme of the first heat dissipation module 30 and the second heat dissipation module 40 of the embodiment of the present application is adopted, that is, after laying a 0.06mm graphene film (i.e., the second heat dissipation module 40) between the heating device 20 and the liquid cooling film (i.e., the first heat dissipation module 30), the heat of the heating device 20 is conducted to the high thermal conductivity graphene film through the thermal interface material, or the shielding cover (not shown in the figure), and then transferred to the liquid cooling film. Exemplarily, a shielding cover and / or a thermal interface material are provided between the heating device 20 and the second heat dissipation module 40. That is, a shielding cover may be provided between the second heat dissipation module 40 and the heating device 20, or a thermal interface material may be provided between the second heat dissipation module 40 and the heating device 20, or a shielding cover and a thermal interface material may be provided between the second heat dissipation module 40 and the heating device 20.

[0122] That is, a second heat dissipation module 40 is provided between the first heat dissipation module 30 and the main heat source (i.e., the heat generating device 20), and the three overlap partially or completely. Compared with the original design, using the same first heat dissipation module 30 (i.e., the above-mentioned liquid cooling film), the screen side average temperature of the combined heat dissipation module (i.e., the first heat dissipation module 30 combined with the second heat dissipation module 40) provided in the embodiment of the present application is about 5°C, and the cross-axis heat transfer capacity is increased by 20%. The heat dissipation capacity is increased by more than 50% compared with cross-axis / through-axis graphite, and the probability of liquid pump startup is reduced by 80%.

[0123] It should be noted that the embodiment of the present application does not impose any specific restrictions on the projection positions of the heating device 20, the first heat dissipation module 30, and the second heat dissipation module 40. That is, along the first direction, the projection of the heating device 20 and the projection of the second heat dissipation module 40 may partially or completely overlap, the projection of the first heat dissipation module 30 and the projection of the second heat dissipation module 40 may partially or completely overlap, and the projection of the first heat dissipation module 30 and the projection of the heating device 20 may partially or completely overlap.

[0124] Embodiment 3

[0125] In some possible implementations, continue to refer to Fig.11 and Fig.13 , the projection of the graphene film of the embodiment of the present application (such as Fig.13 The dotted frame 40 (shown in the middle) covers the projection of the first portion 3011 of the liquid-cooled film 301, the projection of the second portion 3012, and the projection of the bendable area 3013.

[0126] Fig.11 and Fig.13 A high-impedance compensation heat dissipation solution for a folding machine is shown. Table 7 shows the liquid cooling heat gain (Q=3.5W) of the folding machine according to an embodiment of the present application. Table 8 shows the liquid cooling heat gain (Q=3.5W) of the folding machine according to an embodiment of the present application.

[0127] Table 7 Liquid cooling heat gain of folding machine in the present embodiment (Q=3.5W)

[0128] Single temperature difference Temperature difference between upper and lower screens Equivalent thermal conductivity 1. The first heat dissipation module 4.2 6.7 4138 2. Second heat dissipation module 6.9 8.5 1795 3. Composite heat dissipation module 3.1 4.8 5606

[0129] Table 8 Liquid cooling heat gain of folding machine in the present embodiment (Q=2.5W)

[0130] Single temperature difference Temperature difference between upper and lower screens Equivalent thermal conductivity 4. Second heat dissipation module 5.7 4.5 1795

[0131] Similar to the second embodiment, the first heat dissipation module 30 also includes a liquid cooling module, and the liquid cooling module uses water or a composite working medium with water as the main body. The pump 302 of the liquid cooling module drives the working medium to circulate between the cold and heat sources and the upper and lower screens. The second heat dissipation module 40 also includes a graphene film.

[0132] Continue to refer Fig.11 The original design only uses a large area of ​​0.2mm thick liquid cooling film, and the heating device 20 is arranged on the liquid cooling path. In order to reduce power consumption and noise, for the active liquid cooling system (i.e., the liquid cooling module described in this embodiment, i.e., the first heat dissipation module 30), the switch of the pump 302 should be based on the overheating report of the temperature sensor. Under the sudden high load (Boost) and high chip impedance of the heating device 20, startup lag may occur, and the temperature mutation of the chip SOC and the charging chip cannot be fully synchronized.

[0133] like Fig.13 As shown, the first heat dissipation module 30 and the second heat dissipation module 40 of the embodiment of the present application are adopted. After a 0.06 mm graphene film (i.e., the second heat dissipation module 40) is laid between the heating device 20 and the liquid cooling film (i.e., the first heat dissipation module 30), the graphene film is ultra-thin and covers the heating device 20. The heat of the heating device 20 is conducted to the high thermal conductivity graphene film through the thermal interface material or the shielding cover (not shown in the figure), and then transferred to the liquid cooling film.

[0134] That is, a second heat dissipation module 40 is provided between the first heat dissipation module 30 and the main heat source, and the three partially or completely overlap. It should be noted that the embodiment of the present application does not impose specific restrictions on the projection positions of the heating device 20, the first heat dissipation module 30, and the second heat dissipation module 40. That is, along the first direction, the projection of the heating device 20 and the projection of the second heat dissipation module 40 may partially or completely overlap, the projection of the first heat dissipation module 30 and the projection of the second heat dissipation module 40 may partially or completely overlap, and the projection of the first heat dissipation module 30 and the projection of the heating device 20 may partially or completely overlap.

[0135] In daily use scenarios, when the power consumption of the heating device 20 is less than 2.5W (as shown in Table 7), the average temperature of the screen side of the second heat dissipation module 40 is about 5°C, which meets the heat and power consumption requirements, and there is no need to frequently start the liquid cooling system of the pump 302 of the liquid cooling module of the first heat dissipation module 30. In other words, the second heat dissipation module 40 can effectively dissipate heat by 2.5W when the first heat dissipation module 30 is delayed or not started, and the startup probability of the pump 302 is reduced by more than 80% on a daily basis. When a high load occurs, such as Q=3.5W (as shown in Table 8), during the heat accumulation process, before the pump 302 is started, or before the first heat dissipation module 30 is under high load, the combined heat dissipation module (i.e., the first heat dissipation module 30 is combined with the second heat dissipation module 40) provided in the embodiment of the present application can be provided with a basic heat dissipation capacity by the second heat dissipation module 40, and provide a buffer for the first heat dissipation module 30 to avoid local short-term overheating.

[0136] Embodiment 4

[0137] In some possible implementations, reference Fig.14 and Fig.15 , Fig.14 and Fig.15 A high impedance compensation combined heat dissipation solution for folding machines is shown. Fig.14 A schematic diagram showing that the first heat dissipation module 30 is a liquid cooling module, Fig.15 The schematic diagram shows that the first heat dissipation module 30 is a heat spreader or a loop heat pipe.

[0138] like Fig.14 As shown, in some possible embodiments, the first heat dissipation module 30 of the embodiment of the present application includes a liquid cooling module, and the second heat dissipation module 40 includes a graphene film. The graphene film of the second heat dissipation module 40 includes a first portion 41, a second portion 42, and a bendable area 43 connecting the first portion 41 and the second portion 42 of the graphene film.

[0139] Specifically, the first portion 41 of the graphene film is attached to the side of the first portion 3011 of the liquid cooling film 301 facing the heating device 20, along the first direction (eg Fig.16 The projection of the first part 41 of the graphene film covers the projection of the heating device 20; the second part 42 of the graphene film is arranged on the second middle frame 12, and the bendable area 43 of the graphene film passes through or crosses the rotation axis.

[0140] like Fig.15 Shown and combined Fig.16 and Fig.17 In some possible embodiments, the first heat dissipation module 30 of the embodiment of the present application includes a heat sink. The second heat dissipation module 40 includes a graphene film. The electronic device includes a first middle frame 11, a second middle frame 12 and a rotating shaft 13 (such as Fig.16 and Fig.17As shown in FIG, the first middle frame 11 and the second middle frame 12 are rotatably connected by a rotating shaft 13 to switch between a folded position and an unfolded position.

[0141] Specifically, the graphene film includes a first portion 41, a second portion 42, and a bendable region 43 connecting the first portion 41 and the second portion 42 of the graphene film. The heating device 20 and the heat spreader (i.e., the first heat dissipation module 30) are arranged in the first middle frame 11, and the first portion 41 of the graphene film (i.e., the second heat dissipation module 40) is attached to the side of the heat spreader facing the heating device 20. Along the first direction, the projection of the first portion 41 of the graphene film covers the projection of the heating device 20, and the second portion 42 of the graphene film is arranged in the second middle frame 12, and the bendable region 43 of the graphene film passes through or crosses the rotating shaft.

[0142] The second heat dissipation module 40 is laid between the heating device 20 and the first heat dissipation module 30. For example, the second heat dissipation module 40 is a 0.06mm graphene film. The chip SOC, charging chip, etc. (i.e., the heating device 20) are located at the edge of the first heat dissipation module 30 due to structural space reasons, that is, the projection of the first heat dissipation module 30 and the heating device 20 along the first direction partially overlap, but the second heat dissipation module 40 fully covers the heating device 20, that is, the projection of the second heat dissipation module 40 and the heating device 20 along the first direction completely overlap. The heat of the heating device 20 is conducted to the high thermal conductivity graphene film through the thermal interface material or the shielding cover (not shown in the figure) and then transferred to the first heat dissipation module 30, thereby ensuring that the heat is effectively transferred to the first heat dissipation module 30 and the first heat dissipation module 30 works efficiently.

[0143] In daily light-load usage scenarios, when the power consumption of the heating device 20 is less than 3W, for the liquid cooling system of the liquid cooling module (i.e., the first heat dissipation module 30), the second heat dissipation module 40 is used to balance the temperature, and the pump 302 of the first heat dissipation module 30 does not need to be frequently turned on; for the heat spreader (i.e., the first heat dissipation module 30), when the light-load heat spreader is in the temperature range of 35 to 45°C, the heat spreader is still in a high-impedance state, relying on the second heat dissipation module 40 to balance the temperature, and the average temperature on the screen side is about 5°C, which meets the thermal performance and power consumption requirements of the electronic equipment.

[0144] If a high load occurs, when the heat generation Q of the heating device 20 is 4W, in the process of heat accumulation, before the liquid cooling module or the heat spreader is started, that is, before the first heat dissipation module 30 is under high load, the second heat dissipation module 40 provides basic heat dissipation capacity to provide a buffer for the first heat dissipation module 30 to avoid local short-term overheating of the heating device 20. In other words, when the first heat dissipation module 30 is delayed or not started, the second heat dissipation module 40 can effectively dissipate 3W of heat, and reduce the probability of starting the pump 302 by more than 80% on a daily basis.

[0145] Embodiment 5

[0146] In some possible implementations, reference Fig.18 In (a), (b) and (c), Fig.18 (c) is Fig.18 In the locally enlarged area of ​​(b), the second heat dissipation module 40 of the embodiment of the present application includes any one of a hexagonal ring structure material layer and a composite material layer.

[0147] Exemplarily, the hexagonal ring structure material layer includes a graphene film, an artificial graphite sheet, and a boron nitride film, and the thermal conductivity of the second heat dissipation module 40 is ≥50 W / mK.

[0148] Exemplarily, in engineering applications, the second heat dissipation module 40 may be a composite material, that is, it includes a hexagonal ring structure material layer and a non-hexagonal ring structure material layer, an insulating protective film may be provided on the outside, and VCD treatment is used. The composite material layer is, for example, any one of a phase change material (PCM) and a heat storage material (HSM). Exemplarily, for cross-axis and through-axis heat transfer scenarios, the second heat dissipation module 40 may be provided with a steel sheet or Teflon protection. Alternatively, the second heat dissipation module 40 may be attached to the first heat dissipation module 30 as an integral part. Alternatively, the cover plate, film material or tube wall of the first heat dissipation module 30 may be made of the material of the second heat dissipation module 40 so that the first heat dissipation module 30 and the second heat dissipation module 40 are combined into one.

[0149] For example, the surface and interior of the hexagonal ring structure material layer have a plurality of wrinkle structures, and the 1 μm 2 The total length of the wrinkle structure per unit area is in the range of 1 μm to 500 μm. The plurality of wrinkle structures include a plurality of micro wrinkle structures with a length of micron or submicron. The plurality of micro wrinkle structures are irregularly distributed on the surface of the second heat dissipation module 40 .

[0150] It should be noted that the embodiment of the present application does not limit the type of the second heat dissipation module 40. Exemplarily, the second heat dissipation module 40 also includes a graphene-based heat dissipation material with an equivalent thermal conductivity of ≥1000W / mK, including multiple two-dimensional material particle layers, each two-dimensional material particle layer includes multiple two-dimensional material particles, and two adjacent two-dimensional material particles in the multiple two-dimensional material particles are bonded by covalent bonds, and the bonding force is very strong; the two-dimensional material particle layers are bonded by van der Waals forces and can slide and displace. Based on the above characteristics, the graphene-based heat dissipation material has good flexibility, can withstand 200,000 bends, can absorb various impacts and bends, and has good reliability.

[0151] Specifically, Fig.18As shown in (a), (b) and (c), the second heat dissipation module 40 is a hexagonal ring structure material layer, and each hexagonal ring structure is connected by a covalent bond. This microstructure supports the second heat dissipation module 40 to have flexibility and higher impact resistance and vibration resistance, ensuring the continuity of phonon and / or electronic heat conduction.

[0152] Therefore, the embodiment of the present application can provide a stable and unchanging guaranteed heat dissipation solution by the second heat dissipation module 40 that is not easily damaged, maintain basic performance requirements, ensure the guaranteed thermal performance of the system when the first heat dissipation module 30 fails to work, and effectively solve the high impedance state when the first heat dissipation module 30 is working, avoiding the problems of short-term overheating, local burning and overheating shock.

[0153] In summary, for problem (1): the position and change of the heat source (the heating device 20 is close to the edge or there are multiple heating devices 20), the embodiment of the present application partially or completely lays a second heat dissipation module 40 between the heating device 20 and the first heat dissipation module 30. The thermal conductivity or heat dissipation performance of the second heat dissipation module 40 has nothing to do with the position and change of the heat source. The second heat dissipation module 40 completely covers the heating device 20. First, the second heat dissipation module 40 averages the temperature of the concentrated heat source, and after the diffused heat meets the high thermal performance of the first heat source, it is transferred to the first heat dissipation module 30 (single-phase / two-phase liquid cooling module), reducing the constraints of thermal design on the architecture and interconnected heat source layout.

[0154] Regarding problem (2): the startup temperature is low (i.e., the startup temperature is ≤35°C), in the embodiment of the present application, a second heat dissipation module 40 is partially or completely laid between the heating device 20 and the first heat dissipation module 30. The effect of the operating temperature on the thermal conductivity or heat dissipation performance of the second heat dissipation module 40 is much lower than that of the primary heat dissipation module. At low temperatures, the second heat dissipation module 40 provides a low-temperature heat dissipation solution. After the temperature rises to a high temperature, the second heat dissipation module 40 is started up to perform its high performance.

[0155] For problem (3): startup delay (≥0.5 seconds), in the embodiment of the present application, a second heat dissipation module 40 is partially or completely laid between the heating device 20 and the first heat dissipation module 30. The second heat dissipation module 40 has no startup delay phenomenon. The second heat dissipation module 40 that compensates provides a transitional thermal solution for startup delay.

[0156] Regarding question (4): external field force (variable acceleration force, and the influence of centrifugal force and tidal force in non-inertial system), in the embodiment of the present application, a second heat dissipation module 40 is partially or completely laid between the heating device 20 and the first heat dissipation module 30. The thermal conductivity of the second heat dissipation module 40 is independent of changes in acceleration, etc. The second heat dissipation module 40, which is not affected by variable acceleration, provides a stable and constant bottom-line heat dissipation solution to maintain basic performance requirements.

[0157] Regarding problem (5): the heat dissipation module is partially damaged (partially deformed and damaged due to falling during transportation, installation, or operation), in the embodiment of the present application, a second heat dissipation module 40 is partially or completely laid between the heating device 20 and the first heat dissipation module 30. The second heat dissipation module 40 is a hexagonal ring structure material layer, and each hexagonal ring structure is connected by a covalent bond. The surface and interior of the hexagonal ring structure material layer have multiple wrinkle structures, and the multiple wrinkle structures include multiple microscopic wrinkle structures with a length of micrometer or submicrometer level. 1μm 2 The total length of the wrinkle structure per unit surface area is in the range of 1 μm to 500 μm; the plurality of microscopic wrinkle structures are irregularly distributed on the surface of the material layer. The second heat dissipation module 40, which is not easily damaged, provides a stable and constant bottom-line heat dissipation solution to maintain basic performance requirements.

Claims

1. An electronic device, characterized in that: include: A heating device, a first heat dissipation module and a second heat dissipation module; wherein, The first heat dissipation module transfers heat through phase change and / or fluid flow, and the second heat dissipation module transfers heat through phonons and / or electrons; Along the first direction, the second heat dissipation module is arranged between the first heat dissipation module and the heating device, the first heat dissipation module is in contact with the second heat dissipation module, the projection of the heating device and the projection of the second heat dissipation module partially or completely overlap, the projection of the first heat dissipation module and the projection of the second heat dissipation module partially or completely overlap, and the projection of the first heat dissipation module and the projection of the heating device partially overlap.

2. The electronic device according to claim 1, characterized in that: The first heat dissipation module includes any one of a heat spreader, a heat pipe, a loop heat pipe and a liquid cooling module.

3. The electronic device according to claim 1 or 2, characterized in that: The second heat dissipation module includes a hexagonal ring structure material layer.

4. The electronic device according to claim 1 or 2, characterized in that: The second heat dissipation module includes a composite material layer, and the composite material layer includes a hexagonal ring structure material layer and a non-hexagonal ring structure material layer.

5. The electronic device according to claim 3, characterized in that: The hexagonal ring structure material layer includes a graphene film, an artificial graphite sheet, and a boron nitride film.

6. The electronic device according to claim 4, characterized in that: The composite material layer includes any one of a phase change material and a heat storage material.

7. The electronic device according to any one of claims 1 to 6, characterized in that: It also includes a middle frame, the first heat dissipation module includes a heat spreader, and the second heat dissipation module includes a graphene film; The heating device is arranged in the middle frame, the graphene film is attached to a side of the heat spreader facing the heating device, and along the first direction, the projection of the graphene film covers the projection of the heating device.

8. The electronic device according to any one of claims 1 to 6, characterized in that: The electronic device comprises a first middle frame, a second middle frame and a rotating shaft, wherein the first middle frame and the second middle frame are rotatably connected via the rotating shaft to switch between a folded position and an unfolded position; The first heat dissipation module includes a liquid cooling module, the liquid cooling module includes a pump and a liquid cooling film connected to each other, the liquid cooling film is used to supply a cooling medium to flow, and the pump is used to provide power for the flow of the cooling medium in the liquid cooling film; the liquid cooling film includes a first part, a second part, and a bendable area connecting the first part and the second part, the first part of the liquid cooling film is arranged in the first middle frame, the second part of the liquid cooling film is arranged in the second middle frame, and the bendable area of ​​the liquid cooling film passes through or crosses the rotating shaft; The second heat dissipation module includes a graphene film; At least the first middle frame is provided with the heating device, the graphene film is attached to the side of the first part of the liquid-cooling film facing the heating device, and along the first direction, the projection of the graphene film covers the projection of the heating device.

9. The electronic device according to claim 8, characterized in that: The projection of the graphene film covers the projection of the first portion of the liquid-cooling film, the projection of the second portion, and the projection of the bendable area.

10. The electronic device according to claim 8, characterized in that: The graphene film comprises a first portion, a second portion, and a bendable region connecting the first portion and the second portion of the graphene film; The first portion of the graphene film is attached to a side of the first portion of the liquid-cooling film member facing the heating device, and along the first direction, a projection of the first portion of the graphene film covers a projection of the heating device; The second portion of the graphene film is disposed on the second middle frame, and the bendable region of the graphene film passes through or crosses the rotating shaft.

11. The electronic device according to any one of claims 1 to 6, characterized in that: The electronic device comprises a first middle frame, a second middle frame and a rotating shaft, wherein the first middle frame and the second middle frame are rotatably connected via the rotating shaft to switch between a folded position and an unfolded position; The first heat dissipation module includes a heat sink; The second heat dissipation module includes a graphene film, wherein the graphene film includes a first portion, a second portion, and a bendable region connecting the first portion and the second portion of the graphene film; The heating device and the heat spreader are arranged in the first middle frame, the first part of the graphene film is attached to the side of the heat spreader facing the heating device, along the first direction, the projection of the first part of the graphene film covers the projection of the heating device, the second part of the graphene film is arranged in the second middle frame, and the bendable area of ​​the graphene film passes through or crosses the rotating shaft.

12. The electronic device according to any one of claims 3 to 6, characterized in that: The surface and interior of the hexagonal ring structure material layer have a plurality of wrinkle structures, and the 1 μm 2 The total length of the wrinkle structure per unit area is in the range of 1 μm to 500 μm, and the plurality of wrinkle structures include a plurality of microscopic wrinkle structures with a length of micrometer or submicrometer level, and the plurality of microscopic wrinkle structures are irregularly distributed on the surface of the second heat dissipation module.

13. The electronic device according to any one of claims 1 to 12, characterized in that: A shielding cover and / or thermal interface material is provided between the heating device and the second heat dissipation module.

14. The electronic device according to any one of claims 1 to 12, characterized in that: The surface of the second heat dissipation module that is in contact with the heating device is a planar structure.

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