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Highly filled graphite compounds for energy technology - TECACOMP HTE

The structure of a fuel cell is a highly specialized, complex system. Gases involved in the reaction and the cooling media must be separated from each other and dispersed in the reaction areas. For these tasks, bipolar plates have to possess good electrical and thermal conductivity, and at the same time be resistant to chemical, mechanical and thermal stress. Only by fulfilling these requirements can the reliable function of a fuel cell be guaranteed in the long term.
The new TECACOMP HTE material from Ensinger Compounds is a compound which has been specifically developed and optimized for applications of this or a similar type. Their suitability is based on a significantly higher than normal ratio of fillers. This high filling ratio enables a degree of electrical and thermal conductivity which was previously unachiev­able with plastics. At the same time, chemical resistance is also maintained.


Basic polymers and fillers

The polymers propylene (PP) or polyphenylene sulphide (PPS) is used as the basis for TECACOMP HTE. It is able to cover application temperatures ranging from 60° to 200°C.
PPS has already proven its superiority over thermosetting plastic binders in HT PEM (high-temperature polymer electrolyte membrane) fuel cells. PP compounds are suitable for use in NT-PEM (low-temperature polymer electrolyte membrane) fuel cells as well as in direct methanol fuel cells (DMFC) or redox flow batteries.
To achieve the high electrical and thermal ­val­ues required by these applications, carbon-
based fillers such as graphite, carbon black or polymer fibres are mixed with the base polymers for TECACOMP HTE in a ratio of up to 90% by weight.
Depending on the polymer used, the degree of filling and the targeted component size, the formulas are suitable either for processing by injection moulding or compression moulding. This is why the compounds are available in different versions either in powder or in gran­ulate form.

Raw material
Fuel cell

Benefits

Achieved conductivity due to the high graphite content, which has never been achieved before.

Best chemical resistance: The high filling level protects the material against chemical influences.
Variety of production: Depending on the used polymer, the degree of filling and the target size the customer can select between injection molding or hot compression molding.

Compounds: Business Case – Fuel cell

Tests under extreme conditions: The compounds from the TECACOMP HTE series have proven their excellent suitability for PEM fuel cells.