Combustion synthesis and characterization of Ni-doped LiMn2O4 cathode nanoparticles for lithium ion battery applications

Abstract

In this research work, fine powders of spinel-type LiMn 2-x Ni x O 4-δ (where x = 0.1, 0.2, 0.3, 0.4 and 0.5) as cathode materials for lithium ion batteries were synthesized by combustion synthesis using urea as fuel and metal nitrates as oxidizers at a temperature of 600°C. The physiochemical properties of the prepared cathode materials were investigated by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), particle size analysis, energy dispersive analysis (EDAX) and scanning electron microscopy (SEM). The electrochemical characteristics were studied by impedance spectroscopy. It was found that the physical charactetertistics were moderately influenced because of different dopant (Ni) concentration. Among the samples studied, LiMn 1.9 Ni 0.1 O 4-δ resulted in better electrical conductivity (6.49 x 10-5 Scm-1) at room temperature and hence it may be suitable for lithium ion battery applications.

A Comparative Review of Metal Oxide Surface Coatings on Three Families of Cathode Materials for Lithium Ion Batteries

“…Which takes place on the surface of the cathode material to form Mn 2+ ions. The dissolved Mn 2+ ions are the main agents of capacity decrease since a deposit of just one Mn 2+ ion facilitate extraction of two Li + ions out of the lithiated graphite into the cell [67]. Therefore, to obtain high performing Li-ion batteries that are constituted of a spinel cathode material containing Mn, the dissolution of Mn should be minimized.…”

Preparation and High Temperature Electrochemical Performance of LiNi0.08Mn1.92O4 Cathode Material of Submicron Truncated Octahedron

“…掺杂元素的 M-O 键能(M＝Cr、Co、Ni、Al、Fe 等)通常大于 Mn-O 键 能, 掺杂离子是通过取代尖晶石型 LiMn 2 O 4 结构中 16d 位置上的 Mn 3 ＋ , 达到有效抑制 Jahn-Teller 效应, 提高材 料在充放电过程中晶体结构的高温稳定性 [9][10][11][12] . Ni 是 LiMn 2 O 4 正极材料常用的掺杂元素, 可以显著提高其晶 体结构稳定性和电化学性能及电导率 [13][14][15][16][17][18] . Liu 等 [13] 采 用密度泛函第一性原理计算结果表明, Ni 2 ＋ 取代 Mn 3 ＋ 在 热力学上是有利的, 与 Ni 2 ＋ 相邻的 Mn 3 ＋ 被氧化为 Mn 4 ＋ , 降低了 Jahn-Teller 畸变和 Mn 溶解的概率, 且当 Ni 掺杂 浓度为 6.25%时, Ni 掺杂会导致晶胞体积减小约 0.6%.…”