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Sacrificial templating effect of mixed polymer matrix to create surface pores promoting the facile ion flow and close interaction of electrode and electrolyte. • Mixed polymer matrix provided a strong framework to restrict CNT migration. • Hot press proved to have enhance the performance with no structural deformation. • Easy access point for the electrolytes due to the emergence of surface pores. • Exhibited a specific energy of 814 Wh/kg -cell required for electric vehicles. Although Li-air batteries have been recognized as promising next-generation batteries for electric vehicles (EVs), there are still several issues in the development of practical cells that can achieve high specific energies for long driving ranges. In particular, it is important to employ a small amount of electrolyte and prevent it from escaping the cathode material during charging and discharging. Herein, a free-standing web-like mat cathode composed of mixed polymer nanofibers with high CNT loading is reported. High amounts of CNT (ca. 65.8 wt% of the polymer weight) is simultaneously loaded into the as-spun nanofibers with a mixed polymer matrix (consisting of polyacrylonitrile (PAN) and polyvinylpyrrolidone (PVP)). The domain occupied by PVP was converted into pores after a simple washing process, while the remaining PAN domain formed a backbone for the nanofibers. Using this cathode, a practical cell with a specific energy of 814 Wh/kg -cell is successfully developed by applying a controlled optimum ratio of electrolyte to CNT in the cathode. With these results, although still lacking, can provide handful insights and new directions towards development of future electrode materials as well as encourage to pursue strategies that requires minimal processing and activation steps while still achieving industrial acceptable performances. [ABSTRACT FROM AUTHOR]

Abstract A 500 mAh Li–Air battery is assembled using cell components and a structure that enable the construction of a high specific energy battery. Carbon nanotubes are used in the cathode so that the pore volume can be adjusted to reduce the amount of electrolyte while a high specific capacity of the cathode is maintained. Polymer ionic liquid is used in the electrolyte layer, and the weight of the cathode and electrolyte layer is 5.5 mg cm−2. The cell structure, which is prepared by folding a three-layer assembly of Li metal/electrolyte layer/cathode, reduces the weight contribution of the sealing and manifold materials. By folding the three-layer assembly ten times, a 500 mAh Li–Air battery with dimensions of 7 cm × 1 cm × 0.23 cm is prepared. The battery yields an areal capacity of 3.6 mAh cm−2 and a specific capacity of 4400 mAh g carbon −1, and the resulting specific energy and energy density are 1230 Wh kg−1 and 880 Wh L−1, respectively. The battery is able to cycle seven times at 500 Wh kg−1 before an abrupt decrease in its capacity is noted. Graphical abstract Image 1 Highlights • Design of Li–Air battery with specific energy over 1000 Wh kg−1 is presented. • Fold cell structure reduces weight of sealing and manifold materials. • A cell with dimension of 7 cm × 1 cm × 0.23 cm produces 500 mAh. • The battery could be cycled 7 times at the specific energy of 500 Wh kg−1. [ABSTRACT FROM AUTHOR]