Preparation of High Performance Porous Silicon Powders by Etching Al-Si Alloy in Acid Solution for Lithium Ion Battery

Authors

Shi-ji HAO, Shanghai institute of space power-sources, Shanghai 200245, China;
Chun-li LI, Shanghai institute of space power-sources, Shanghai 200245, China;
Kai ZHU, Shanghai institute of space power-sources, Shanghai 200245, China;
Ping ZHANG, Shanghai institute of space power-sources, Shanghai 200245, China;
Zhi-yu JIANG, Department of chemistry, Fudan University, Shanghai 200433, China;Follow

Corresponding Author

Zhi-yu JIANG(zyjiang@fudan.ac.cn)

Abstract

Porous silicon powders prepared by etching Al-Si alloy using an acid solution was reported in the first time. The morphology and structure of as-obtained material were investigated using scanning electron microscopy (SEM) and X-ray diffraction (XRD) method. It was found that the spongy porous silicon powders presented well crystalline structure and consisted of nano-Si particles. The particle size of porous Si powders was about 20 μm, and the specific surface area was 102.7 m²·g^-1. The electrochemical properties of porous silicon powders were evaluated as an anode material for lithium ion batteries. The material proportion in the porous silicon electrode was porous Si:conducting C:binder = 1:1:1. It was measured that in 1 LiPF₆ mol·L^-1, EC:DMC = 1:1 + 15%(by mass)FEC electrolyte, the first discharge capacity of porous silicon electrode was 2072 mAh·g^-1 Si, and the capacity of 1431 mAh·g^-1 Si was kept after 237 cycles at the charge and discharge current densities of 100 mA·g^-1. Such high electrochemical performance of porous silicon electrode could be attributed to the spongy porous structure, which provided enough tiny space to buffer the huge volume variation of Si anode during charging/discharging process. The nano-size of Si particles was benefited to the diffusion process of lithium in Li-Si alloy, and the firm connection between Si nanoparticles could prevent the breakage of porous Si particles. This advanced method for producing high performance porous Si powders is simple and low cost, and has a bright prospect for the practical application

Graphical Abstract

Keywords

lithium-ion batteries, porous silicon, silicon electrode, Al-Si alloy, fluoroethylene carbonate

DOI Link

https://doi.org/10.13208/j.electrochem.130426

Publication Date

2014-02-25

Online Available Date

2014-02-24

Revised Date

2013-07-01

Received Date

2013-04-26

Recommended Citation

Shi-ji HAO, Chun-li LI, Kai ZHU, Ping ZHANG, Zhi-yu JIANG. Preparation of High Performance Porous Silicon Powders by Etching Al-Si Alloy in Acid Solution for Lithium Ion Battery[J]. Journal of Electrochemistry, 2014 , 20(1): 1-4.
DOI: 10.13208/j.electrochem.130426
Available at: https://jelectrochem.xmu.edu.cn/journal/vol20/iss1/1