Synthesis and characterization of LiNi0.5Mn0.4Co0.1O2 as a cathode material for lithium-ion batteries using the coprecipitation method

Abstract

This study explores the synthesis and electrochemical characterization of LiNi_0.5Mn_0.4Co_0.1O₂ (NMC541) as a cathode material for lithium-ion batteries. Utilizing a coprecipitation method, the research aims to enhance energy storage capacity and thermal stability. The precursor Ni_0.5Mn_0.4Co_0.1(OH)₂ was pyrolyzed and mixed with lithium hydroxide, followed by calcination at temperatures of 700, 800, and 850 °C to optimize phase composition and crystallinity. Morphological and structural characterizations were performed using TEM, SEM, XRD, and Raman spectroscopy. Electrochemical performance was assessed in coin cells through cyclic voltammetry, electrochemical impedance spectroscopy, and charge–discharge tests, revealing significant improvements in energy density and thermal stability under optimized conditions. Notably, the NMC541 sample calcined at 800 °C for 8 h demonstrated a homogeneous particle distribution and relatively uniform particle sizes, corresponding to the highest conductivity value of 5.099 × 10⁻³ S·cm⁻¹. The average particle size was 129.834 nm, and when assembled in a coin cell, the configuration exhibited a discharge capacity of 97.72 mAh·g⁻¹ and an efficiency of 74.40% during the 50 cycles charge–discharge testing. Compared to traditional cathode materials like NMC333 (LiNi_0.33Mn_0.33Co_0.33O₂) and NCA (lithium nickel-cobalt-aluminum oxide), NMC541 offers notable advancements. The higher nickel content in NMC541 contributes to increased capacity, while the balanced proportions of manganese and cobalt ensure enhanced structural stability and safety. The comparative analysis highlights that NMC541 provides improved energy density, thermal stability, and cycling performance, making it a formidable candidate for next-generation lithium-ion batteries.