Analisis Pengujian Konsentrasi Redox Mediator dan Lama Waktu Perendaman Pada Regenerasi Limbah Katoda LiFePO4

Alim, Almas Kurnia (2026) Analisis Pengujian Konsentrasi Redox Mediator dan Lama Waktu Perendaman Pada Regenerasi Limbah Katoda LiFePO4. Masters thesis, Institut Teknologi Sepuluh Nopember.

Text 6011242004-Master_Thesis.pdf - Accepted Version Restricted to Repository staff only Download (13MB) | Request a copy

Abstract

Meningkatnya limbah baterai Lithium Iron Phosphate (LFP) mendorong kebutuhan metode daur ulang yang efisien dan berkelanjutan. Penelitian ini mengevaluasi pengaruh konsentrasi litium hidroksida (LiOH) dan lama perendaman pada suhu ruang terhadap regenerasi langsung katoda LFP bekas menggunakan sistem mediator redoks LiI/LiOH dalam etanol. Serbuk katoda bekas (S-LFP) dikarakterisasi menggunakan X-Ray Diffraction (XRD), Scanning Electron Microscope with Energy Dispersive X-Ray (SEM-EDX), Electrochemical Impedance Spectroscopy (EIS), Galvanostatic Charge Discharge (GCD), Differential Capacity (dQ/dV), dan Galvanostatic Intermittent Titration Technique (GITT). Hasil karakterisasi menunjukkan S-LFP telah mengalami delitiasi parsial dengan volume kisi menyusut hingga 280,917 Å3. Regenerasi optimum dicapai pada konsentrasi 0,25 M selama 90 menit, yang berhasil merestorasi volume kisi menjadi 290,967 Å3 (ekspansi ~3,6% mendekati LFP murni). Uji elektrokimia membuktikan pemulihan kinetika yang signifikan: hambatan transfer muatan (Rct) turun drastis sebesar 99,6% (dari 1774,9 Ω pada kondisi 0,5M 30 menit menjadi 7,62 Ω), sementara koefisien difusi ion litium (DLi+) mencapai 7,29×10-11 cm2s-1, setara dengan material komersial. Elektroda optimal menghasilkan kapasitas stabil ~107 mAhg-1 pada 0,1C, meningkat 32% dibandingkan material komersial (~81 mAhg-1), dengan retensi kapasitas mencapai 97,6%. Sebaliknya, konsentrasi (0,5 M) terbukti merusak sistem; residu basa menginisiasi oksidasi pelarut organik dan dehidrofluorinasi pengikat PVDF, menghasilkan arus semu yang mendistorsi Coulombic efficiency hingga >138% dan menghancurkan antarmuka elektroda. Secara fundamental, metode regenerasi suhu ruang ini hemat energi, efisien waktu (90 menit), dan mampu memulihkan kinetika fasa padat melampaui material komersial, menawarkan solusi berkelanjutan untuk daur ulang baterai LFP skala industri.
========================================================================================================================
The escalating volume of spent Lithium Iron Phosphate (LFP) batteries necessitates the development of effective and sustainable recycling methods. This study evaluates the effects of Lithium Hydroxide (LiOH) concentration and soaking time on the room-temperature direct regeneration of spent LFP cathodes using a LiI/LiOH redox mediator system in ethanol. The spent cathode powder (S-LFP) was characterized using XRD, SEM-EDX, EIS, GCD, dQ/dV, and GITT. Characterization results indicated that S-LFP had undergone partial delithiation, with the lattice volume shrinking to 280.917 Å3. Optimal regeneration was achieved at 0.25 M for 90 minutes, which successfully restored the lattice volume to 290.967 Å3 (approximately 3.6% expansion, approaching pristine LFP). Electrochemical testing confirmed significant kinetic recovery: the charge transfer resistance (Rct) decreased drastically by 99.6% (from 1774.9 Ω at 0.5M 30 min to 7.62 Ω), while the lithium-ion diffusion coefficient (DLi+) reached 7.29×10-11 cm2s-1, comparable to commercial-grade material. The optimized electrode delivered a stable capacity of approximately 107 mAhg-1 at 0.1C, representing a 32% improvement over commercial LFP (~81 mAhg-1), with a capacity retention of 97.6%. Conversely, excessive concentration (0.5M) proved destructive; residual base initiated organic solvent oxidation and PVDF binder dehydrofluorination, generating spurious currents that distorted Coulombic efficiency beyond 138% and degraded the electrode interface. Fundamentally, this room temperature regeneration method is energy efficient, time efficient (90 minutes), and capable of restoring solid state kinetics that surpass commercial materials, offering a sustainable solution for industrial scale LFP battery recycling.

Item Type:	Thesis (Masters)
Uncontrolled Keywords:	Baterai LiFePO4, Daur Ulang, Direct Regeneration, Room Temperature, Litium Hidroksida. LiFePO4 Battery, Recycling, Direct Regeneration, Room Temperature, Lithium Hydroxide, Lithium Ethoxid
Subjects:	T Technology > TD Environmental technology. Sanitary engineering > TD794.5 Recycling (Waste, etc.) T Technology > TK Electrical engineering. Electronics Nuclear engineering > TK2921 Lithium cells. T Technology > TK Electrical engineering. Electronics Nuclear engineering > TK2941 Storage batteries T Technology > TL Motor vehicles. Aeronautics. Astronautics > TL220 Electric vehicles and their batteries, etc.
Divisions:	Faculty of Industrial Technology > Material & Metallurgical Engineering > 27101-(S2) Master Thesis
Depositing User:	Almas Kurnia Alim
Date Deposited:	29 Jul 2026 01:39
Last Modified:	29 Jul 2026 01:39
URI:	http://repository.its.ac.id/id/eprint/139036

Actions (login required)

View Item