Research progress of inorganic solid electrolytes in foundmental and application field

全固态锂电池由于具有安全性高、循环寿命长、能量密度高等特点,在高安全化学电源领域具有非常好的应用前景。固体电解质材料是全固态锂电池的核心,迄今被研究过的锂离子固体电解质体系很多,但性能好的材料较少。NASICON型结构氧化物、石榴石型结构氧化物、硫化物体系等锂离子固体电解质在室温下具备高离子电导率,是最具有应用前景的3类锂离子固体电解质材料。本文针对近年来国内外在这3类固体电解质材料方面的研究现状,主要从其结构特征、制备方法、改性研究等方面进行了简要的概括,归纳出各种电解质材料的特点,最后阐述锂离子固体电解质材料应用于全固态锂电池中面临的挑战和发展的前景。     

Sol–gel synthesis of Li1.5Al0.5Ge1.5(PO4)3 solid electrolyte

The effect of calcination on Li ion conductivity of Li_1.5Al_0.5Ge_1.5(PO₄)₃ (LAGP) solid electrolyte prepared by a sol–gel method is examined. The Li ion conductivity of LAGP increases with calcination temperature. After reaching maximum conductivity at 850 °C, the conductivity decreases with increase of the calcination temperature. The calcination holding time also strongly affects Li ion conductivity of LAGP. The conductivity increases with holding time until 12 h and then decreases. It is found that the control of crystallization rate is critical to obtain bulk LAGP with high Li ion conductivity. The highest bulk and total conductivities at 30 °C are 9.5×10⁻⁴ and 1.8×10⁻⁴ S cm⁻¹, respectively, obtained for the bulk LAGP calcined at 850 °C for 12 h.