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Lithium-ion polymer batteries of aluminium-laminated packaging structure have advantages in terms of thermal characteristics and safety but have a weak configuration with respect to external forces compared with other types of cells such as cylindrical and prismatic cells. Thus it is important to protect the batteries of the aluminium-laminated packaging structure under the severe conditions encountered in vehicle operation where excessive mechanical impacts and vibrations may affect the battery system. In this work, an energy storage system for a hybrid electric vehicle (HEV) has been developed using lithium-ion polymer battery cells with an aluminium-laminated packaging structure and has been tested for structural and electrical durabilities. The test results of combined accelerated vibration and charge-discharge cycling are presented to prove that the battery pack has the durability to satisfy vehicle standards. Three different types of test method have been applied to evaluate the mechanical and electrical durabilities. It was observed that the HEV battery pack satisfied the durability standards required for vehicle applications. The results imply that an aluminiumlaminated cell packaging structure can be a competitive option for physical configuration of cells for vehicle applications.

Boron-doped graphitized carbon nanofibers (CNFs) were prepared by optimizing CNFs preparation, surface treatment, graphitization and boron-added graphitization. The interlayer spacing (d₀₀₂) of the boron-doped graphitized CNFs reached 3.356 Å, similar to that of single-crystal graphite. Special platelet CNFs (PCNFs), for which d₀₀₂ is less than 3.400 Å, were selected for further heat treatment. The first heat treatment of PCNFs at 2800 °C yielded a d₀₀₂ between 3.357 and 3.365 Å. Successive nitric acid treatment and a second heat treatment with boric acid reduced d₀₀₂ to 3.356 Å. The resulting boron-doped PCNFs exhibited a high discharge capacity of 338 mAh g⁻¹ between 0 and 0.5 V versus Li/Li⁺ and 368 mAh g⁻¹ between 0 and 1.5 V versus Li/Li⁺. The first-cycle Coulombic efficiency was also enhanced to 71-80%. Such capacity is comparable to that of natural graphite under the same charge/discharge conditions. The boron-doped PCNFs also exhibited improved rate performance with twice the capacity of boron-doped natural graphite at a discharge rate of 5 C.