Sn-Ni合金的电化学沉积法制备与性能

利用直流电沉积法在铜箔上沉积了锂离子电池负极材料Sn-Ni合金,并对其结构和电化学性能进行了表征和分析。所得Sn-Ni合金材料的粒径在1～2mm之间,主要成分为Ni3Sn2和Sn。将电沉积有Sn-Ni合金的铜箔经过干燥、压片后直接作为锂离子电池负极,其首次可逆比容量达到516mAh/g,首次库仑转换效率在75%。而传统涂浆法制备的Sn-Ni合金电极,首次可逆比容量为416mAh/g,首次库仑转换效率仅为27.5%。与传统涂浆工艺相比,直流电沉积法直接获得的Sn-Ni合金负极首次循环的可逆容量、库仑效率都有明显优势,但循环性仍有待于进一步提高。

Preparation and properties of Sn-Ni alloy by electrochemical deposition

The anode material Sn-Ni alloy for Li-ion battery was deposited onto a copper foil by direct current electrodeposition. Its structure and electrochemical properties were characterized. It was indicated that the as-deposited alloy was composed of Ni3Sn2 and Sn with grain size in the order 1~2 mm. The copper foil collector deposited Sn-Ni alloy was used as the anode directly in the Li-ion battery after a step of dry and press treatment. The electrodeposited Sn-Ni alloy anode showed initial reversible specific capacity was 516 mAh/g and initial coulomb efficiency was 75%. Comparatively, the slurry-coating anode from Sn-Ni alloy only gave the initial reversible specific capacity 416 mAh/g and initial coulomb efficiency 27.5%. It is visible that the initial reversible specific capacity and coulomb efficiency of the electrodeposited Sn-Ni alloy anode are higher than those of the slurry-coating anode from Sn-Ni alloy. For the electrodeposited Sn-Ni alloy anode in the Li-ion battery, it is needful to improve its cycle performance.