电沉积Sn-Ni合金锂离子电池负极材料的研制

Development of Sn-Ni Anode with Electrodeposition

通过电沉积锡镍合金制备了Sn-Ni锂离子电池负极材料。对沉积膜层进行了XRD及EDX分析,表明得到的合金主要包括Ni3Sn2,Ni3Sn4,Sn等相,其中Sn/Ni之比约1.5(原子比)。添加剂及工艺优化有利于得到可用作负极材料的均匀沉积膜层。分析讨论了此膜层电极的充放电过程及循环伏安(CV)曲线,测量了其循环容量。电极最大放电容量约为517 mAh.g-1,20次循环放电容量约144 mAh.g-1,除第一个循环有一定容量损失外,前20次充放电效率基本在92%以上。相对于所沉积的Sn电极,Sn-Ni合金中的Ni提高了电极性能,特别是充放电循环稳定性。

Sn-Ni anode was prepared with electrodeposition method.XRD analysis showed that the electrodeposited film,in which Sn and Ni was in the mole ratio of 1.5 indicated by EDX measurement,was primarily composed of Ni3Sn2,Ni3Sn4,Sn, Ni,Sn oxide,etc.Sn-Ni electrodeposition was modified to obtain a uniform film needed for the anode material in lithium battery by the additive in electrolyte bath and optimum conditions.Charge/discharge characteristics of electrodeposited Sn-Ni anode were examined,as well as cyclic voltammetry（CV）.It was shown that the maximum discharge capacity of the electrode was about 517 mAh·g-1,and the discharge capacity was kept around 144 mAh·g-1 at the 20th cycle,the coulomb efficiency was above 92% at the first 20 cycles of charge/discharge.The electrode performance,particularly the cycling stability,was effectively improved due to Ni in Sn-Ni film,in contrast to that of electrodeposited Sn anode.