Author:
Gao Yao,Fan Lei,Zhou Rui,Du Xiaoqiong,Jiao Zengbao,Zhang Biao
Abstract
AbstractSi is a promising anode material for Li ion batteries because of its high specific capacity, abundant reserve, and low cost. However, its rate performance and cycling stability are poor due to the severe particle pulverization during the lithiation/delithiation process. The high stress induced by the Li concentration gradient and anisotropic deformation is the main reason for the fracture of Si particles. Here we present a new stress mitigation strategy by uniformly distributing small amounts of Sn and Sb in Si micron-sized particles, which reduces the Li concentration gradient and realizes an isotropic lithiation/delithiation process. The Si8.5Sn0.5Sb microparticles (mean particle size: 8.22 μm) show over 6000-fold and tenfold improvements in electronic conductivity and Li diffusivity than Si particles, respectively. The discharge capacities of the Si8.5Sn0.5Sb microparticle anode after 100 cycles at 1.0 and 3.0 A g−1 are 1.62 and 1.19 Ah g−1, respectively, corresponding to a retention rate of 94.2% and 99.6%, respectively, relative to the capacity of the first cycle after activation. Multicomponent microparticle anodes containing Si, Sn, Sb, Ge and Ag prepared using the same method yields an ultra-low capacity decay rate of 0.02% per cycle for 1000 cycles at 1 A g−1, corroborating the proposed mechanism. The stress regulation mechanism enabled by the industry-compatible fabrication methods opens up enormous opportunities for low-cost and high-energy–density Li-ion batteries.
Funder
Shanghai Jiao Tong University
Publisher
Springer Science and Business Media LLC
Subject
Electrical and Electronic Engineering,Surfaces, Coatings and Films,Electronic, Optical and Magnetic Materials
Cited by
11 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献