Preparation And Electrochemical Performance Of Cathode For Aqueous Sodium Ion Battery

As the electrode material of Sodium ion battery,Manganese oxide attracted extensive attention.Usually,the capacity of the layered Manganese oxide is higher,but its electronic conductivity and stability are poor.The capacity of tunnel type Sodium Manganese oxide sodium is lower due to its low Sodium storage quantity.These shortcomings limit the application of Manganese oxide on Sodium ion batteries.In this paper,to make its structure more stable,improve the electrical conductivity,promote ion diffusion and increase the capacity of the materials,we adopt the approach of doping and pre-intercalation to modify Manganese oxide.Then we character the structure and morphology,test its electrochemical performance and analyze the results.Flower-like MnO₂ is prepared by hydrothermal method with pre-intercalation of Potassium Sodium ions.The electrochemical test results show that the conductivity is enhanced and the diffusion impedance decreased.When the ratio of Sodium and Potassium is 10:1,the specific capacity of pre-intercalated MnO₂ is 133.8 mA h g-1 at 0.1C.After 100 cycles,the retention ratio of the discharge specific capacity is 100%.A series of irregular block structure Na0.44MnO₂ material have been successfully synthetized via a simple solid phase method.Mn are partly replaced by Titanium.Among them,the Na0.66Ti0.34Mn0.66O₂ with the highest Sodium storage shows outstanding electrochemical performance,such as a high specific capacity of 80 mA h g-1at 1 C and excellent rate capability.