High-energy And Long Cycle Life Rechargeable Aqueous Ion Battery Electrochemical Performance And Its Application

Batteries with good-safaty,low-cost and long cycle life are demanded for large scale energy storage such as smart grid,uninterrupted power supply and so on.Due to its low-cost,good-safety,rechargeable aqueous ion battery is well worth developing.Traditional batteries such as lead-acid battetries occupy the most part of the markethas.But its energy density is only 30 Wh/kg and it uses heavy metal and sulfuric acid electrolyte which result in serious environment pollution.In the long run,it is necessary to develop eco-friendly rechargeable aqueous ion battery with high energy density and long cycle life.1?The Na0.44MnO2 has been used as cathode material in rechargeable aqueous in battery with specific capacity of 45 mAh g-1.Through solid-phase reaction,NaMnO2 was synthesized which exhibits both pseudocapacitance and intercalation/extraction properties delivers high specific capacity of 65 mAh g-1 at a rate of 1 C.Coupled with NaTi2(PO4)3 anode material,the full cell exhibits an energy density of 30 Wh kg-1 at a power density of 50 W kg-1.If using 1 M Na2S04 as the electrolyte,the full cell could only retain 25%of the initial capacity after 500 cycles.Through ICP-AES and XRD analysis,we found that the NaMn02 goes through irreversible structure collapse and Mn dissolution in 1 M Na2SO4 electrolyte.After 500 cycles,the full cell could remain 75%of the initial capacity using 2 M CH3COONa electrolyte.2?The narrow stable electrochemical window of aqueous electrolyte(1.2 V)is the intrinsic limit that results in low operation voltage and energy output.Here,through adding sodium dodecyl sulfate(SDS)in aqueous electrolyte adjusting electrode-electrolyte interphase,the stable electrochemical window of water can be expanded to about 2.2 V.Density functional theory calculation,the SDS surfactant forms an adsorption layer on the electrode surface with hydrophilic group facing the electrode and hydrophobic group facing the medium,which effectively suppress the hydrogen/oxygen evolution.A rechargeable aqueous battery using Na2MnFe(CN)6 nanocubes as cathode material and zinc metal as anode material is assembled and exhibits energy density of 170 Wh kg-1.We develop a strategy high concentration electrolyte could increase the energy barrier of water electrolysis and suppress hydrogen or oxygen evolution.Thus the aqueous electrolyte stable window can be successfully expanded to about 3.2 V.The TiS2 was first used as negative electrode material delivered a high capacity of 140 mAh g-1.The full cell exhibited high energy density of 100 Wh kg-1.3?Large-scale synthesis of NaTi2(PO4)3 anode material.The as-synthesized material delivered capacity of 130 mAh g-1 with uniform particle and high compaction density.Coupled with LiMnO2 cathode material,the full cell can exhibit a capacity of 4 Ah with high energy density of 40 Wh kg-1 which is much higher than that of lead-acid battery(30 Wh kg-1).And the battery remain 75%initial capacity after 1500 cycles which is much longer than lead-acid battery(about 300 cycles).The full cell cost is about 0.15 dollar per Wh.The high energy density and low-cost make the as-assembled battery possible commercial application for energy storage applications.