Preparation Hollow Spherical Mn-Based Anode Materials And Their Lithium Storage Performence For Lithium Ion Battery

Thanks to the advantages of manganese, such as abundant in nature and low-cost etc. manganese has been one of the important elements for energy storage materials. In terms of Lithium-ion batteries, Mn-based anode materials has been widely researched due to its high specific capacity, safety performance and so on. However, its weaknesses also are prominent, for example low electronic conductivity, severe cycling capacity fading and poor rate capability. With purpose of improving electronic conductivity, carbon-introduced and metal-doped has been ased for electrode materials in lithium-ion batteries. Besides, the construction of hollow sphere structure could ease the volume expansion during charge and discharge process so that cycle performance can be improved significantly. In our work, template-sacrificial route, kirkendall effect, has been applied to synthesis different hollow sphere Mn-based anode materials of LIBs. Moreover, the relationship of morphology and electrochemical performance has been investigated. The (?)searches in details are as follow. 1、Hollow spherical Ni-doped MnO@C(Ni/MnO@C) composites are achieved through a mechanism analogy to kirkendall effect and carbon reduction, exhibit excellent electrochemical performance when it is as anode material for lithium ion batteries. Possessing a highly specific capacity of514.4mAh·g-1in the100th cycle at a current density of200mh·g-1. good rate capacity of368.7mAh·g-1at a current density of2A·g-1. The high electrochemical performances of the as-prepared Ni/MnO@C composites could be attributed to their unique structure, in which the metal Ni particle improve the electronic conductivity and have some catalytic effects. Also, the carbon layer protect the body material MnO from dissolving by electrolyte.2、Hollow spherical NiMn2O4electrode material is achieved through a mechanism analogy to kirkendall effect. And investigate the temperature influence to morphology and material composition. Sample calnied at750℃has the best unbroken morphology and electrochemical performance. Possessing a highly specific capacity of386mAh·g-1in the200th cycle at a current density of200mh·g-1. good rate capacity of350mAh·g-1at a current density of1A·g-1. The high electrochemical performances could be attributed to hollow spherical structure. It is beneficial to alleviate the volume expansion during charge and discharge process, and icrease the contact area between electrode material and electrolyte.consequently, the material NiMn2O4demonstrate good cycle performance and rate performance.