Innovative Tin and hard carbon architecture for enhanced stability in lithium-ion battery anodes
Rana Faisal Shahzad, Shahid Rasul, Mohamed Mamlouk, Cecil Cherian Lukose, Rana Abdul Shakoor, Abdul Wasy Zia
Abstract
Tin (Sn), with a theoretical capacity of 994 mAh g-1, is a promising anode material for lithium-ion batteries (LIBs). However, fundamental limitations like large volume expansion during charge-discharge cycle and confined electronic conductivity limit its practical utility. Here, we report a new material design and manufacturing method of LIB anodes using Sn and Hard Carbon (HC) architecture, which is produced by Physical Vapor Deposition (PVD). A bilayer HC/Sn anode structure is deposited on a carbon/copper sheet as a function of deposition time, temperature, and substrate heat treatment. The developed anodes are used to make cells with a lithium-ion electrolyte using a specific fabrication process. The morphology, atomic structure, conductivity, and electrochemical performance of the developed HC/Sn anodes are studied with SEM, TEM, XPS, and electrochemical techniques. At a discharge rate of 0.1C, the Sn heated + HC anode performs exceptionally well, offering a capacity of 763 mAh g-1. It is noteworthy that it achieves a capacity of 342 mAh g-1 when fast charging at 5C, demonstrating exceptional rate capability. The Sn heated + HC anode maintains >97 % Coulombic efficiency of its capacity after 3000 cycles at a rate of 0.1C after 3000 cycles 730.5 mAh g-1 recorded, demonstrating an impressive cycle life. The novel material design approach of the Sn heated + HC anode, which has a multi-layered structure and HC acting as a barrier against volumetric expansion and improving electronic conductivity during battery cycling, is perceived as influential in uplifting anode's performance. • High Capacity & Material Design : Tin (Sn) has a theoretical capacity of 994 mAhg -1 ; combining Sn with Hard Carbon (HC) addresses its limitations like volume expansion and low conductivity. • Manufacturing : The anode is made with Physical Vapor Deposition (PVD) as a bilayer HC/Sn structure on a carbon/copper sheet. • Optimization & Characterization : Deposition process is optimised by varying time, temperature, and heat treatment; characterized using SEM, TEM, XPS, and electrochemical methods. • Performance : The Sn+HC anode delivers 763 mAhg -1 at 0.1 C and 342 mAhg -1 at 5 C for fast charging. • Cycle Life : It maintains over 97% Coulombic efficiency after 3,000 cycles at 0.1 C, showcasing durability and efficiency.