P2H compounds: Polymer-based electrical heating components

Application-oriented development of innovative electrical heating components based on conductive polymers

Heating foil

Polymer-based heating foil: First functional prototype

Functional demonstrator

Functional demonstrator of electrically heatable heat-shrink tubing (center and bottom in the picture) and state-of-the-art trace heating (top in the picture)

Project goals

The "Power2Heat Compounds" project leverages a core expertise of Fraunhofer UMSICHT – the development of conductive polymer foils using the patented powder-to-roll manufacturing process – for heating applications. To date, the materials have primarily been used in the manufacture of electrodes for electrochemical reactors.

Furthermore, a novel type of heat-shrink-tubing, employing a patent-pending process, is being further developed. This polymer-based, electrically conductive tubing, which can be shrunk using hot air, demonstrates the ability to heat pipes or other three-dimensional objects upon electrical connection.

The project aims to develop energy- and resource-efficient, cost-effective and sustainable heating components tailored for specific applications. A pioneering aspect involves the continuous production of two-dimensional, plastic-based, large-area electrical surface heating elements through a powder-to-roll process as well as extrudable, electrically heatable heat-shrink-tubing. The scientific challenge lies in effectively blending polymers with fillers to optimize electromechanical and thermal properties in the final product. The application-specific selection of the base polymer, as well as appropriate fillers and their proportions, is paramount to fine-tuning specific resistance and thus heating performance. Potential applications span surface heating elements, wearables, pipe trace heating, and dedicated industrial applications.

Project benefits

The "Power2Heat Compounds" project carries significant societal implications, especially within the context of the transition to sustainable heating and the revision of the Building Energy Act. Since January 1, 2024, newly installed heating systems are required to utilize at least 65% renewable energy sources. The utilization sourced from renewables is more attractive than ever, driven by ecological imperatives and the current energy crisis. In scenarios where heat pumps are no feasible option, direct electric heating systems emerge as a viable alternative. Particularly in the refurbishment of older structures, electric wall heating systems present advantages over traditional heat transfer systems in terms of building physics. Leveraging the thin foil-based materials from Fraunhofer UMSICHT enables the development of resource-efficient, cost-effective, and reliable solutions compared to conventional panel heating elements. The material's adjustable flexibility and rigidity render it suitable for a diverse range of applications.

Furthermore, distinctive product attributes such as formability, laminability, and weldability present novel design opportunities. These characteristics allow for the creation of end products that align with the current EU draft directive aimed at promoting goods repairability. Lastly, the development of heatable, heat-shrinkable tubing within the project presents an innovative alternative to the heating tapes and cords currently prevalent in the market. These advancements unlock new avenues, particularly in pipe trace heating for applications such as heat retention or frost protection in industries like processing and food. Through their form-fit enclosure of the target medium, they ensure uniform heat distribution, thereby enhancing energy efficiency. Moreover, they are characterized by superior functional reliability compared to heating cords, typically constructed with resistance wires. Even in the event of surface damage, the heating remains operational, preventing total failure - a scenario that would occur with a broken heating cord.

Project results

Surface heating elements Panel thickness < 1 mm
Area-specific heat output > 5 W / cm²
Heatable heat shrink tubing Hose thickness < 1 mm
Length-specific heat output > 100 W / m
Shrinkage ratio at least 2:1 
For both applications Homogeneous heat distribution
Temperature gradient: max. 10 K

Development strands in the project

Development strands in the project "Power2Heat Compounds: Application-oriented development of novel electrical heating components based on conductive polymers"
© Fraunhofer UMSICHT
Development strands in the project "Power2Heat Compounds: Application-oriented development of novel electrical heating components based on conductive polymers"

Video demonstrating the basic function of the heat-shrink-tubing

Funding information

 

Duration: January 2024 to December 2026

Funding code: SME 40-08036

Website: www.fraunhofer.de

The project "Power2Heat Compounds: Application-oriented development of novel electrical heating components based on conductive polymers" is funded as part of the internal programs of the Fraunhofer-Gesellschaft. Reference number: SME 40-08036.