Preparation And Properties Of Sn（SnO₂） Anode Materials For Lithium-ion Batteries

Since its small portable device, high potential, good cycle performance, and no pollution, lithium-ion batteries is widely used in mobile phones, laptops, and other electronic products, showing great prospect in new-energy storage and electronic car.However, the current theoretical specific capacity of carbon anode materials seem to be relatively low. Because Sn has high specific capacity, we choose Sn as replacement.However Sn will produce drastic volume change in the charge and discharge process, the results would lead to crack of material’s surface, even pulverization. In order to solve this problem, we put Sn anode materials for our research object, starting from controlling its morphology and structure, compounding with carbon materials and alloying with relatively insert materials. We use hydrothermal method and electrostatic spinning to prepare anode materials. We use SEM, TEM, XRD, Raman, to analyse its microscopic composition and structure, and using electrochemical performance, constant voltage,constant current to test its electrochemical performance. This paper has carried out the work mainly including the following three aspects.1. We use hydrothermal method to prepare the twins of Sn@C, and compare with pure Sn electrochemical performance, After twenty cycles, the capacity is still more than 400mAhg-1, which improving its cycle performance to a certain extent. This is because we made smaller particle size of compound and the carbon acted as a base to buffer the volume expansion of materials.2. We further prepare SnO2@RGO compound by hydrothermal method, and optimize the synthesis process. After calcination in the temperature 180, we equip battery and then test electrochemical performance. The compound’s capacity remains above 410 m Ahg-1 under the current density of 0.25 C after fifty cycles, and still show good perfect electrochemical performance under the current density of 0.5 C, 1 C, 2C.3. We use electrostatic spinning to prepare SnO2/TiO2 cathode materials respectively. The SnO2/TiO2 show great rate performance under the current density of0.1 C, 0.2 C, 0.5 C, 1 C, 2 C, the whole process of coulomb efficiency can be stable at around 85%.