An Investigation On Performance Of Zinc Manganese Dioxide Battery Influenced By Double Cation Electrolyte

With the development of science and technology,the problems of energy decay and environmental pollution are becoming increasingly serious.Lithium-ion batteries are in the leading position in energy storage batteries and are widely used in the world which have the advantages of high operating voltage,high energy density and long cycle life.However,problems such as limited lithium resource reserves and flammable organic electrolytes cannot meet people’s needs for environmentally friendly secondary batteries.Therefore,it is of great significance to develop a new type of high-safety next-generation secondary battery.Aqueous zinc ion batteries are receiving increased attentions due to abundant and high safety.Finally,the prevalence of an aqueous zinc ion battery voltage is too low,the capacity and the cycle rapid decay of poor stability,to achieve practical applications are still a great challenge.In this paper,aiming at the key problems existing in the aqueous zinc ion battery,starting from the reaction mechanism of charge and discharge of manganese dioxide(MnO2)electrode material,the electrochemical performance of Zn//MnO2 battery is regulated by the design of double cation electrolyte,and the mechanism of structural transformation of positive material in the process of electrode circulation is discussed,which provides a new idea for the design of aqueous electrolyte with excellent circulation performance.The main research results are as follows:Firstly,aluminum ion was introduced into the electrolyte to control the electrochemical performance of Zn//α-MnO2 battery.The performance of α-MnO2 cathode material battery was tested after the introduction of aluminum ions,and the behavior of storing double cation ions in α-MnO2 structure was studied.It is found that the electrolyte containing aluminum ions can improve the charge discharge voltage of Zn//α-MnO2 battery,and the structural changes of the charge discharge products are studied by means of SEM,TEM,X-ray diffraction and other characterization methods to clarify the reaction mechanism.Finally,high energy density Zn//β-MnO2 batteries were obtained.The β-MnO2 cathode material was prepared,and its electrochemical properties and the structure of charge discharge products were studied.It was found that the discharge voltage of Zn//β-MnO2 battery was increased and the discharge capacity was increased by 1.6 times.The energy density based on the cathode material is 622 Wh kg-1.And it has good intercalation/deintercalation reversibility and excellent cycle stability.Therefore,the design of double cation electrolyte provides an effective method for the preparation of high energy density water zinc ion batteries.