Abstract

LiNiPO₄ has been the focus of research in developing environmentally friendly, low cost and high performance cathode materials for lithium-ion batteries. The aim of this work is to synthesize LiNi_0.5Co_0.45Zn_0.05PO₄ cathode material using solid-state reaction method at 850 °C for 20 hours and all the parameters compared with LiNiPO₄. The X-ray diffraction (XRD) analysis confirmed that LiNi_0.5Co_0.45Zn_0.05PO₄ phase is well crystallized with olivine structure indexed by orthorhombic symmetry with Pnma space group. The phase purity supported by energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM). Local structure of the LiNi_0.5Co_0.45Zn_0.05PO₄ phospho-olivine material has been investigated by Fourier transforms infrared spectra (FTIR). All the parameters of LiNi_0.5Co_0.45Zn_0.05PO₄ are found in good agreement with XRD, FTIR results of LiNiPO₄. Impedance spectroscopy technique has been used to study the cathode materials because it can reveal the relationship between the crystal lattice with the electrochemical properties.

摘要

LiNiPO ₄一直是开发环保，低成本和高性能锂离子电池正极材料的研究重点。这项工作的目的是通过固态反应方法在850°C下20小时并与LiNiPO ₄进行比较，以合成LiNi _0.5 Co _0.45 Zn _0.05 PO ₄正极材料。X射线衍射（XRD）分析证实，LiNi _0.5 Co _0.45 Zn _0.05 PO ₄相结晶良好，橄榄石结构由Pnma的正交对称性索引空间群。能量分散光谱（EDS）和扫描电子显微镜（SEM）支持相纯度。LiNi _0.5 Co _0.45 Zn _0.05 PO ₄磷酸橄榄石材料的局部结构已通过傅立叶变换红外光谱（FTIR）进行了研究。发现LiNi _0.5 Co _0.45 Zn _0.05 PO _4的所有参数与LiNiPO _4的XRD，FTIR结果吻合良好。阻抗光谱技术已用于研究正极材料，因为它可以揭示晶格与电化学性质之间的关系。