Fabrication Of Sn Film Via Magnetron Sputtering Towards Understanding Electrochemical Behavior In Lithium-ion Battery Applications

Tin (Sn) attracts considerable attention as an anode material for lithium-ion batteriesdue to its high theoretical capacity. In the present work, Sn thin film composed ofnumerous continuous Sn particles was prepared on a copper foil via magnetron sputtering.We have investigated the electrochemical properties of the Sn thin film, as anodeelectrode in lithium ion batteries.In this thesis, Sn thin films with different size of Sn particles were prepared byadjusting the time of sputtering. Sn thin film composed of numberous Sn particles(ranging from25to200nm) exhibited the best electrochemical performance with adischarge capacity of420mAh g-1after50cycles.To understand the process of Sn volume change, the process of Sn volume changewas investigated via SEM. Modifying the surface of Sn electrode with a conductor wasachieved after a thin conductive layer (copper or carbon) was sputtered onto the Snelectrode after cycling30times. The Sn-MS-Cu and Sn-MS-C elec-trodes showed anincrease in electrochemical performance, the modifying electrodes delivered highcapacity of520mAh g-1(Sn-MS-Cu) and550mAh g-1(Sn-MS-C) after50cycles.Finally, Sn-Cu alloy (Cu3Sn) was synthesized by annealing the as-prepared Sn thinfilm (fabricated via magnetron sputtering.) Electrochemical performance results showedthat the sample annealed at200℃for2h exhibited the best electrochemical properties.The discharge capacity was440mAh g-1after50cycles, which was much higher than thatof the as-prepared Sn thin film (420mAhg-1).