锌掺杂固态电解质材料磷酸钛铝锂的制备及第一性原理研究

高安全性的固体锂离子电池是目前研究的热点之一,固态电解质是研究全固态电池的关键.磷酸钛铝锂固体电解质(LATP)具有良好的发展空间,因此采用高温固相法,制备锌掺杂LATP(LAZTP)固体电解质,通过XRD、SEM分析对比其物象和形貌特征,并对这两种材料压片进行阻抗分析,研究材料的电化学性能.基于密度泛函理论的第一性原理,研究LAZTP的能带结构和态密度与材料电化学性能的关系.结果表明:所掺杂锌的LATP材料,在球磨工艺下,与LATP相比衍射峰尖锐,材料结晶度良好,都为R-3C结构,LAZTP微观尺度下材料颗粒清晰,呈块状,孔隙均匀致密度较好,离子电导率相比较高,为1.9×10^-3S/cm,而制作的LATP的电导率为4.02x10^-4 S/cm,掺杂后的电导率明显高出一个数量级.计算得出的LATP能带带隙为0.163 eV和LAZTP能带带隙为0.05 eV,分态密度中Ti-s、Li-s、Al-s峰值尖锐,变化明显,表明掺杂锌后,材料明显提高了导电率和结构稳定性.

Preparation and first-principles study of zinc-doped solid electrolyte material Li1.3AI0.3Ti1.7(PO4)3

High-safety solid lithium-ion batteries are one of the current research hotspots. Solid electrolytes are the key to studying all-solid-state batteries. Lithium titanium aluminum phosphate solid electrolyte (LATP) has good development space, so high-temperature solid-phase method is used to prepare zinc Doped with LATP (LAZTP) solid electrolyte, compare its image and morphological characteristics through XRD and SEM analysis, and conduct impedance analysis on the two materials to study the electrochemical performance of the material. Based on the first nature of density functional theory the principle is to study the relationship between the energy band structure and density of states of LAZTP and the electrochemical properties of the material. The results show that the LATP material doped with zinc, under the ball milling process, has sharper diffraction peaks and good crystallinity than LATP. R-3C structure, the LAZTP are clear and massive at the microscopic scale, the pores are uniform and dense, and the ion conductivity is relatively high, 1.9×10-3S/cm, while the conductivity of the produced LATP The rate is 4.02x10-4S/cm, and the conductivity after doping is significantly higher by an order of magnitude. The calculated band gap of LATP is 0.163 eV and the band gap of LAZTP is 0.05 eV, and the split state density is Ti-s , Li-s, Al-s peaks are sharp, and the changes are obvious, indicating that after doping with zinc, the material significantly improves the conductivity and structural stability.