Malays. J. Anal. Sci. Volume 30 Number 1 (2026): 1387

Research Article

Iron loading effect on graphite/carbon black/polypropylene composite of bipolar plate’s mechanical and electrical properties

Mohd Zulkefli Selamat^1,2,*,Muhammad Yusri Md Yusuf^1,2,,Abu Bakar Sulong³, Musthafah Mohd Tahir^1,2, Hamzaitul Akmarizal Hamdan^1,2

¹Centre of Advanced Research on Energy (CARe), Faculty of Mechanical Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 76100 Durian Tunggal, Melaka, Malaysia

²Department of Mechanical and Materials Engineering Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia 43600 Bangi, Selangor, Malaysia

^*Corresponding author: zulkeflis@utem.edu.my

Received: 28 October 2024; Revised: 10 October 2025; Accepted: 30 October 2025; Published: 28 February 2026

Abstract

In polymer electrolyte membrane fuel cells (PEMFC), the materials used for bipolar plates must meet stringent requirements, including high mechanical strength, lightweight, low cost, ease of fabrication, low contact surface resistance, and mechanical stability. Moreover, the performance and properties of these plates are significantly influenced by the materials and their compositions. In this study, all raw materials were used in powder form. The conductive fillers employed were graphite (G), carbon black (CB), and iron (Fe), while polypropylene (PP) was utilized as the polymer binder. The overall composition ratio of fillers to binder was maintained at 80:20 by weight. Within the filler component, the composition was adjusted within the following ranges: 40–50 wt% for graphite, 25 wt% for carbon black, and 5–20 wt% for iron. The fillers were initially blended using a ball milling process to ensure uniform dispersion. Prior to this, compounding of the fillers and the polymer binder was carried out using an internal mixer machine. The compounded material was then processed via hot compression moulding to fabricate the G/CB/Fe/PP composite plates. Subsequently, various performance evaluations were conducted, including in-plane electrical conductivity, mechanical properties (flexural strength and shore hardness), bulk density, and microstructural analysis. Among the samples tested, the composite containing 15 wt% Fe exhibited the most favourable properties, achieving the highest in-plane electrical conductivity of 367.59 S/cm, flexural strength of 44.57 MPa, bulk density of 1.69 g/cm³, and shore hardness of 60.2, respectively.

Keywords: bipolar plate, graphite, carbon black, ferum, conductive filler, and PEMFC

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