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Latent thermal storage in metals can overcome many issues related to the temporal or spatial intermittency of heat resources, particularly in the provision of heat in electric vehicles. Alloys that are energy dense and thermally conductive are most attractive for thermal storage applications. The eutectic alloy, Al‐25% Cu‐6% Si (wt%) has been identified as an optimal metallic phase change material melting in the temperature range 508°C to 548°C. Through differential scanning calorimetry, light flash analysis and long‐term reaction experiments, the thermal and compatibility characteristics of this alloy are experimentally determined. Graphite and alumina are observed as compatible housing materials for the alloy after 2 weeks at 550°C. Reaction depth and products at the interface with iron and stainless steel are identified with energy‐dispersive X‐ray spectroscopy and electron backscatter diffraction analysis. A volumetric energy density of 0.7764 ± 0.0178 kWh/L was calculated for an operating range of 160°C to 660°C from the measured properties, suggesting the material is an excellent candidate for thermal storage in electric vehicles. [ABSTRACT FROM AUTHOR]

Battery-powered electric buses currently face the challenges of high cost and limited range, especially in winter conditions, where interior heating is required. To face both challenges, the use of thermal energy storage based on metallic phase change materials for interior heating, also called thermal high-performance storage, is considered. By replacing the battery capacity through such an energy storage system, which is potentially lighter, smaller, and cheaper than the batteries used in buses, an overall reduction in cost and an increase of range in winter conditions could be reached. Since the use of thermal high-performance storage as a heating system in a battery-powered electric bus is a new approach, the requirements for such a system first need to be known to be able to proceed with further steps. To find these requirements, a review of the relevant state of the art of battery-powered electric buses, with a focus on heating systems, was done. Other relevant aspects were vehicle types, electric architecture, battery systems, and charging strategies. With the help of this review, requirements for thermal high-performance storage as a heating system for a battery-powered electric bus were produced. Categories for these requirements were the thermal capacity and performance, long-term stability, mass and volume, cost, electric connection, thermal connection, efficiency, maintenance, safety, adjustment, and ecology. [ABSTRACT FROM AUTHOR]