High capacity and temperature adaptive aqueous zinc ion batteries through Ca 2+ intercalated into NH 4V 4O 10 cathode materials

Ammonium vanadate has been extensively studied as a promising electrode material for energy-storage devices with the tunable layered structure. Nevertheless, the excessive extraction of NH4+ leads to the irreversible structure degradation and capacity decrease in cycling process. In this work, we introduce Ca2+ into the NH4V4O10 samples via a simple hydrothermal route, which stabilizes the interlayer structures. At a current density of 0.2 A·g−1, the assembled cells possess a discharge specific capacity of 547.9 mAh·g−1. In addition, they still operate steadily at diverse temperatures from 20 to –20 °C. The soft-packaged devices also present remarkable mechanical properties under various folding degrees.