Graphite Graphene Composite Material for High Thermal Conductivity
Solution Overview
Problem
Existing materials with high in-plane thermal conductivity, such as graphite, face challenges in achieving thickness without compromising thermal conductivity due to cracking during heat treatment and adhesive use, or suffer from low thermal conductivity when thickened through lamination.
Innovation Solution
A graphite/graphene composite material is developed by stacking flat graphite particles using graphene aggregates as a binder, allowing for adjustable thickness and maintaining high thermal conductivity in the in-plane direction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If graphite is heat-treated from polymer to achieve high thermal conductivity, then thermal conductivity is improved, but thickness is limited due to cracking
Solution Approach 1:
The invention changes the fundamental parameter of graphite formation by using graphite intercalation compounds as starting material instead of polymer, and applies heat treatment under controlled pressure and temperature conditions to achieve both high thermal conductivity and increased thickness without cracking
Solution Approach 2:
The invention creates a composite structure by intercalating graphite layers with compounds, then heat-treating to form a consolidated graphite material that combines the high thermal conductivity of graphite with enhanced mechanical strength that prevents cracking during thickening
2Length of stationary object
If adhesive is used to laminate thin graphite materials to increase thickness, then thickness is improved, but thermal conductivity is deteriorated
Solution Approach 1:
The invention extracts and eliminates the adhesive layer from the graphite structure by using heat treatment to directly consolidate graphite particles into a thick, unified material, thereby removing the thermal resistance that adhesives introduce while achieving the desired thickness
3Length of stationary object
If expanded graphite is rolled and press-molded to achieve thickness, then thickness is improved, but thermal conductivity is reduced
Solution Approach 1:
The invention changes the processing parameters by applying controlled heat treatment at specific temperatures and pressures to graphite intercalation compounds, transforming the structure to achieve both thickness and high thermal conductivity simultaneously, rather than relying on room-temperature rolling and press-molding
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composite material achieves high thermal conductivity, crystallinity, and bending strength, enabling effective heat dissipation in both in-plane and thickness directions, suitable for heat collectors, conductors, and dissipators.
Implementation Method 1
flat graphite particles are stacked using the graphene aggregates as a binder so that basal surfaces of the graphite particles are overlapped with one another
Implementation Method 2
graphite having excellent thermal diffusivity... heat conductivity in the in-plane direction reaches to 2500 W/(m·K)
Data Source
AI summary
The present invention provides a graphite/graphene composite material comprising flat graphite particles and graphene aggregates, wherein the flat graphite particles are stacked using the graphene aggregates as a binder so that the basal surfaces of the graphite particles are overlapped with one another, and the graphene aggregates are composed of deposited single-layer or multi-layer graphenes.