Continuous Graphite Film Production via Segmented Heating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for producing graphite films through continuous carbonization result in fragile carbonized films that are prone to wrinkling and cracking due to shrinkage during the process, making them difficult to wind and use effectively.
Innovation Solution
A method involving a continuous carbonization step with multiple heating spaces, where the polymer film is heat-treated in a temperature range of 500°C to 1000°C, with controlled temperature differences between stages and optional cooling spaces, to minimize shrinkage and reduce wrinkling and cracking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If continuous carbonization is performed in a single heating space, then productivity is improved, but the carbonized film becomes fragile with wrinkles and cracks due to shrinkage
Solution Approach 1:
The continuous carbonization process is divided into multiple heating spaces (first heating space and second heating space) with different temperature conditions. The first heating space operates at a lower temperature (500-800°C) to carbonize the polymer film while the second heating space operates at a higher temperature (800-1000°C) to graphitize the carbonized film. This segmentation allows gradual transformation that reduces shrinkage-induced wrinkles and cracks while maintaining continuous production capability.
Solution Approach 2:
The invention changes the temperature parameter progressively across different heating spaces. By controlling the temperature gradient (lower in the first heating space, higher in the second heating space) and adjusting the heating rate, the film undergoes controlled carbonization and graphitization that minimizes abrupt shrinkage. This parameter change strategy resolves the contradiction by enabling continuous processing while maintaining film integrity.
2Productivity
If high temperature heating is applied to carbonize the polymer film, then carbonization efficiency is improved, but shrinkage increases causing wrinkles and cracks
Solution Approach 1:
The heating process is segmented into two distinct stages in two different heating spaces. The first heating space provides milder heating (500-800°C) for initial carbonization with controlled shrinkage, while the second heating space provides intense heating (800-1000°C) for complete carbonization and graphitization. This segmentation allows efficient carbonization while maintaining surface quality by avoiding abrupt high-temperature exposure.
Solution Approach 2:
The first heating space performs preliminary carbonization at a controlled temperature before the film enters the second heating space. This preliminary action partially carbonizes the film in a controlled manner, reducing subsequent shrinkage when exposed to higher temperatures in the second heating space, thereby preventing wrinkles and cracks while maintaining carbonization efficiency.
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
This approach effectively reduces wrinkling and cracking in the carbonized films, allowing for more manageable and flexible graphite films with improved thermal diffusivity, enabling them to be wound around smaller diameters without defects.
Implementation Method 1
a continuous carbonization step of continuously baking a polymer film that continues lengthwise
Implementation Method 2
two or more heating spaces
Implementation Method 3
the inclusion of cooling spaces to minimize shrinkage
Data Source
AI summary
A graphite film with fewer wrinkles and/or undulations is obtained providing two or more stages of heating space and carrying out continuous baking. Especially when a cooling space is provided between each of the heating spaces and another, a graphite film can be obtained which is excellent in flatness and has a high thermal diffusivity.