A self-healing Sn anode with an ultra-long cycle life for sodium-ion batteries. Issue 45 (1st November 2018)

• Record Type: Journal Article
• Authors: Kim, Changhyeon; Kim, Icpyo; Kim, Huihun; Sadan, Milan K.; Yeo, Hyewon; Cho, Gyubong; Ahn, Jaepyoung; Ahn, Jouhyeon; Ahn, Hyojun
• Is Part Of: Journal of materials chemistry. Volume 6:Issue 45(2018)
• Page Start: 22809
• Page End: 22818
• Publication Date: 2018-11-01
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c8ta09544b
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Self-healing of a well-designed Sn anode with ultra-long cycle life and stable high capacity. Abstract : For a next-generation sodium battery to replace lithium ion batteries, it is essential to develop an anode with a long cycle life and high rate. Sn is considered to be an ideal candidate for the anode of sodium ion batteries. Here, we report a Sn anode that exhibits ultra-long-term cycle stability with a high capacity of 554 mA h g −1 at 10C-rate for 5000 cycles. The optimized cell configuration consists of 1, 2-dimethoxyethane as the electrolyte, a double separator including a nanoporous membrane, and a Sn anode with MWCNT as a conductive additive. Its capacity retention reaches up to 99.8% and its coulombic efficiency is near 100% for 5000 cycles. Surprisingly, we have discovered that the Sn powder exhibits a self-healing phenomenon during cycling. Sn is initially pulverized into a nanometer-sized powder, and then forms a three-dimensional porous coral-like structure in which ligament-shaped micrometer-sized Sn particles are connected with a low coordination number by room temperature sintering. The coral-like structure is mechanically stable towards volume change and electrically connected. The self-healing structure and mechanism provide a direction for the design of other electrodes with alloying mechanisms.