A correlation between the crystal structure, the ionic conductivity and the electrochemical performance in Lithium-ion batteries was established for a series of NASICON-type phosphates Li_0.5M_0.5Ti_1.5Fe_0.5(PO₄)₃ (M = Mn, Co, Mg). These electrode materials, where the M1 site contains both lithium and the divalent cation M, were prepared using a simple sol-gel process while controlling the pH and the final synthesis temperature. The three phosphates crystallize in the rhombohedral system (S.G. R-3c) with comparable unit cell parameters but with slight difference in the local distortion of the PO₄ tetrahedra as confirmed by the Raman study. The ionic conductivities of the Li_0.5M_0.5Ti_1.5Fe_0.5(PO₄)₃ materials were measured at different temperatures using a wide range of frequencies. Mn-based phosphate shows the best features for application as electrode material for Li-ion batteries in term of the conductivity at room temperature and the activation energy of Li⁺ conduction process. The initial discharge capacity of 100 mAh.g ^− 1 was obtained for the Mg-based phosphate, 104.3 mAh.g ^− 1 for the Co-based material while the Mn-based material delivers the best first discharge capacity of 125.3 mAh.g ^− 1 with the lowest polarization in relation with its better conduction properties. This result was also confirmed by the rate capability tests where Mn-based phosphate shows enhanced electrochemical performance even at fast rate of 5C.

建立了一系列 NASICON 型磷酸盐 Li _0.5 M _0.5 Ti _1.5 Fe _0.5 (PO ₄ ) ₃ ( M  = Mn, Co, Mg ）。这些电极材料，其中 M1 位点包含锂和二价阳离子 M，使用简单的溶胶-凝胶工艺制备，同时控制 pH 值和最终合成温度。三种磷酸盐在菱面体系统 (SG R-3c ) 中结晶，晶胞参数相当，但 PO ₄的局部变形略有不同拉曼研究证实了四面体。Li _0.5 M _0.5 Ti _1.5 Fe _0.5 (PO ₄ ) ₃材料的离子电导率在不同温度下使用宽范围的频率进行测量。就室温下的电导率和 Li ⁺传导过程的活化能而言，锰基磷酸盐显示出作为锂离子电池电极材料的最佳应用特性。初始放电容量为100 mAh。镁基磷酸盐的g  ^{-  1}为 104.3 mAh。克 ^{-  1}对于 Co 基材料，而 Mn 基材料提供了 125.3 mAh 的最佳首次放电容量。g  ^{-  1}具有与其更好的传导特性相关的最低极化。倍率性能测试也证实了这一结果，其中锰基磷酸盐即使在 5C 的快速倍率下也显示出增强的电化学性能。