The Li₂MnSiO₄ as a novel cathode material for lithium ion batteries, performs high specific capacity, high thermal stability, low cost and etc. However, it suffers from relatively low electronic conductivity and lithium ion diffusion rate. Herein, we successfully introduce fluorine to Li₂MnSiO₄ (Li₂MnSiO_4-xF_x, x = 0.00, 0.01, 0.03 and 0.05) to overcome these obstacles. The results show that F doping not only enlarges the lattice parameters but also decreases the particle size, synergistically improving the lithium ion diffusion of Li₂MnSiO₄. Moreover, F doping increase electronic conductivity of Li₂MnSiO₄/C by inhibiting the formation of C-O bonds in the carbon layers. Meanwhile, F doping improves the crystallinity and stabilizes the crystal structure of Li₂MnSiO₄. Finally, the Li₂MnSiO_3.97F_0.03/C with the best electrochemical performances delivers the initial specific discharge capacity of 279 mA h g⁻¹ at 25mA g⁻¹ current density from 1.5 V to 4.8 V. Also, it maintains a higher capacity (201 mA h g⁻¹) than F-free Li₂MnSiO₄ (145 mA h g⁻¹) after 50 cycles.

作为锂离子电池的新型正极材料的Li ₂ MnSiO ₄具有高的比容量，高的热稳定性，低成本等。然而，其具有相对低的电子传导性和锂离子扩散速率。在本文中，我们成功地将氟引入到Li ₂ MnSiO ₄（Li ₂ MnSiO _4-x F _x，x = 0.00、0.01、0.03和0.05）中以克服这些障碍。结果表明，F掺杂不仅增大了晶格参数，而且减小了粒径，协同改善了Li ₂ MnSiO ₄的锂离子扩散。此外，F掺杂增加了Li的电子电导率₂ MnSiO ₄ / C通过抑制碳层中CO键的形成。同时，F掺杂改善了结晶度并稳定了Li ₂ MnSiO ₄的晶体结构。最后，具有最佳电化学性能的Li ₂ MnSiO _3.97 F _0.03 / C在1.5 mA至4.8 V的25mA g ^-1电流密度下可提供279 mA h g ^-1的初始比放电容量。此外，它还保持了较高的容量（在50个循环后比无F ₂ Li ₂ MnSiO ₄（145 mA h g ^-1）高出201 mA hg ^-1）。