The Preparation And Research Of Tin-Based Alloy Used As Anode Materials For Lithium Battery

Carbonaceous materials are currently used as anode materials in commercial lithium ion batteries. The need for smaller and lighter battery products promotes the search for new anode materials. Tin and tin-based alloys are promising materials to replace carbonaceous materials in lithium ion batteries. The research and development of anode materials for lithium ion battery has been reviewed, especially tin-based materials. The preparation, characteristics and electrochemical performance of Sn-Cu alloy, Sn-Co alloy and Sn-Co/C composites were studied in this dissertation.The porous Sn-Cu alloys were prepared by annealing. The electrochemical properties of the alloys were investigated by charge-discharge test and cyclic voltammetry. And the impact of processing conditions on the electrochemical performance of the porous Sn-Cu alloys was investigated. Results showed that it was good to add more verdigris and to make the annealing time longer for improving the performance. However, the problem of capacity fading can not be solved completely by this method.The Sn-Cu alloys with shell structure were prepared to reduce the problem of volume expansion. The morphology and composition of these alloys were charactered by SEM and ED. The electrochemical properties of the alloys were investigated by charge-discharge test and cyclic voltammetry. And the mechanism of Li-insertion was investigated. The impact of processing conditions such as the temperature and the time of annealing on the electrochemical performance of the alloys was also investigated.Sn-Co alloys were prepared by chemical reduction and ball milling, and the electrochemical performance of the alloys was investigated. The alloys exhibited good cycle performance and high capacity in the initial cycles. It was found that the reversible capacity of Sn-Co alloy prepared by chemical reduction retained 600mAh·g-1 after 25 cycles.Heat-treatment could enhance electric contact among crystal grains in particles and between the alloy and the substrate, thus the performance was improved obviously. It was found that the reversible capacity of Sn-Co alloy annealed at...