Electrochemical Characteristics of Micrometer-sized Sn and Acetylene Black Composites Prepared by Mechanical Milling for Sodium-ion Battery Anodes

Abstract

Five types of micrometer-sized Sn and acetylene black (AB) composite powders were prepared by mechanical milling for 1, 3, 6, 12, and 24 h. The Sn/AB powders obtained, in addition to Sn-only powders were added to a binder and conductive material, and then dried under vacuum to prepare negative electrodes (anodes) for sodium-ion batteries (SIBs). SIBs were fabricated with the anodes in the form of 2032type coin cells, and were evaluated using charge-discharge tests up to 50 cycles within the cutoff voltage range of 0.005-0.65 V at a constant current of 50 mA g −1 at 25°C. Maximum discharge capacities of 614 to 651 mAh g −1 were obtained with all the anodes prepared with both the Sn-only and the Sn/AB composites. However, the discharge capacities of the Sn-only and Sn/AB composites milled for 1 and 3 h were significantly decreased as the charge-discharge cycle increased. In contrast, the Sn/AB composites milled for 6 h or more exhibited improved cycle characteristics; capacities of 635, 619, and 584 mAh g −1 were maintained during 50 cycles of testing with the Sn/AB_6h, Sn/AB_12h, and Sn/AB_24h samples, respectively, which were significantly higher than the anode prepared with the Sn-only powder (135 mAh g −1 ).

Electrochemical evaluation of Sn/C composites as high-performance anodes for sodium-ion batteries

“…The mass mixing ratio of Sn and the CM was fixed at 7 : 1. The rotation speed for milling was fixed at 300 rpm, and the milling time was set to 6 h. We previously reported that the peak width of the Sn/ AB particles was almost unchanged when milled for more than 6 h [21]. In this paper, the composite of Sn and CM is expressed as Sn/ CM, and the composites of Sn and individual CMs are denoted as Sn/ AB, Sn/GR, and Sn/AN.…”

“…This leads to the exfoliation of the Sn active material from the current collector during the charge-discharge cycle, which in turn causes capacity deterioration. To overcome this limitation, the following materials have been used to prepare Sn-based anodes: 1) nanometer-sized Sn [12,13], 2) Sn/C composites developed using Sn compounds and carbon materials (CMs) [14][15][16][17], and 3) Sn/C composites prepared using Sn metal powder and CMs [18][19][20][21]. Each of the above examples is described below:…”

Efficient Surface Passivation of Ti-Based Layered Materials by a Nonfluorine Branched Copolymer for Durable and High-Power Sodium-Ion Batteries

“…The urge for the worldwide development of renewable energy production has shed light on the crucial role played by energy storage devices. , Among them, lithium-ion batteries (LIBs) certainly improved our lives with their high energy density, which led them to be widely used in consumer electronics, hybrid and electric vehicles, and renewable energy storage in grids. − However, to guarantee the earth’s environmental sustainability through this worldwide energetic transition, the technological answer should be based on abundant materials . In this context, sodium-ion batteries (SIBs) arise as the ideal solution. − Among candidates for negative electrode materials, carbon-based materials, such as hard carbon and three-dimensional graphene, have been extensively studied due to their ability to store sodium within their pores, reaching ∼300 mA h g –1 . ,, For practical use, batteries require not only high energy density but also good performance under elevated current density. Because of the high proportion between these carbon-based materials’ sodium operating potential and sodium plating potential, alternative materials are needed for higher rate applications.…”