Garnet-type solid Li ion conductor Li₇La₃Zr₂O₁₂ (LLZO) has received considerable attention due to its high total (bulk + grain boundary) ionic conductivity at room temperature and its chemical stability with Li metal. To improve the ionic conductivity of LLZO, the hetrovalent doping at Zr-site and Al-doping at Li site was done for the optimization of Li concentration in LLZO. Thus, considering prominent role of various dopant in ionic and/or electronic conduction of LLZO, the effect of Mn-doping at Zr-site in the Al-doped Li_6.25+yAl_0.25La₃Zr_2-yMn_yO₁₂ (y = 0, 0.05, 0.1, 0.2) on the microstructure, dielectric and transport properties is studied. The Mn-doping at Zr-site in Al-LLZO is confirmed by electron paramagnetic resonance and X-ray photoelectron spectroscopy techniques. A correlation between structure, microstructure and the Li⁺ ion conduction is established. Amongst all investigated compounds, Li_6.35Al_0.25La₃Zr_1.9Mn_0.1O₁₂ exhibit highest total ionic conductivity of 0.34 × 10⁻⁴ Scm⁻¹ at 25 °C. Further, the electrochemical window and stability of Mn doped-LLZO with Li metal is examined by cyclic voltammetry.

石榴石型固体锂离子导体Li ₇ La ₃ Zr ₂ O ₁₂（LLZO）由于其在室温下较高的总（体相+晶界）离子电导率以及其与Li金属的化学稳定性而备受关注。为了提高LLZO的离子电导率，对Zr位的异价掺杂和Li位的Al掺杂进行了优化，以优化LLZO中的Li浓度。因此，考虑到各种掺杂剂在LLZO的离子和/或电子传导中的显著作用，在Al掺杂的Li _{6.25 + y} Al _0.25 La ₃ Zr _2-y Mn _y O _12中，Zr位处的Mn掺杂效应。（y = 0，0.05，0.1，0.2）对微观结构，介电性能和传输性能进行了研究。通过电子顺磁共振和X射线光电子能谱技术证实了Al-LLZO中Zr位的Mn掺杂。建立了结构，微观结构与Li ⁺离子传导之间的相关性。在所有研究的化合物中，Li _6.35 Al _0.25 La ₃ Zr _1.9 Mn _0.1 O ₁₂在25°C下具有最高的总离子电导率，为0.34×10 ^-4 Scm ^-1。此外，通过循环伏安法检查了具有Li金属的Mn掺杂的LLZO的电化学窗口和稳定性。