A Design and Feasibility Framework for Agro-Waste Bio-Composite Battery Casings in Electric Two/Three-Wheelers

The rapid growth of electric two- and three-wheelers has intensified demand for lightweight, thermally safe and sustainable battery enclosures. Conventional metallic casings are heavy and carbon-intensive, while plastic and glass-fibre composite casings lack adequate thermal stability and fire resistance. This paper reviews the current state of battery thermal management system (BTMS) casings and natural-fibre bio-composites, and proposes a design and fabrication framework for an agro-waste bio-composite casing for 18650 lithium-ion battery modules arranged in a 13s4p configuration. The proposed casing combines banana-pseudostem-fibre-reinforced bio-epoxy with boron nitride, alumina and ammonium-polyphosphate flame-retardant additives, compression-moulded with integrated passive cooling vents and cell-holding inserts. The literature synthesis shows that, although composite battery enclosures and flame-retardant natural-fibre composites have each been studied extensively, very little reported work combines agro-waste fibres, passive thermal venting and flame retardancy within a single casing purpose-built for cost-sensitive 2W/3W platforms. On the basis of the reviewed benchmarks, the proposed casing framework is targeted to achieve a 20-30% weight reduction over metal casings while meeting UL-94/limiting-oxygen-index (LOI) flame-safety benchmarks. The framework presented here defines the material formulation, mould design and characterization matrix that will guide the fabrication and testing phases of the ongoing project, and is directly applicable to EV battery-pack manufacturers and thermal-component suppliers seeking sustainable, cost-effective casing solutions.