Microstructures and Electrochemical Properties of Si1-xNix Alloys

D.Y. Jeong, J.J. Jeong, S.M. Bae, W-W Park, K.Y. Sohn
Inje Univercity, KR

Keywords: silicon alloys, melt spinning, lithium-ion battery, anode materials, nickel

Summary:

Silicon is an attractive anode material for secondary lithium-ion batteries because of its high specific energy capacity of 4200(mAh/g). Silicon-based secondary batteries, however, have poor cycleability due to large volume change during Li+ insertion and extraction. The cycle behavior is known to be improved as the size of silicon decreased to a nanometer scale. The incorporation of inactive matrix to the nanometer scale of silicon is also helpful enhancing the cycle behavior. In this work, nickel is added to silicon to form an intermetallic second phase. The objective of this work is to investigate the effect of relative volume fraction of a Si-Ni second phase on the microstructures and electrochemical behavior of the rapidly solidified alloys. The cycle performance of Si-Ni alloys were significantly influenced by the relative volume fraction of Si2Ni phase. The electrochemical behavior of the Si-Ni alloys will be discussed in terms of microstructures and volume fraction of intermetallic phases.