The development of practical magnesium batteries is severely hindered by the sluggish solid diffusion processes resulting from the relatively high charge density of Mg²⁺ with two unit charges. Therefore, exploiting novel charge storage mechanisms to overcome the inherent kinetic obstruction is urgently needed. Herein, the rapid diffusion kinetics of Mg²⁺ in Wadsley-Roth phase TiNb₂O₇ (TNO) is realized through the electrochemical Li⁺ intercalation boosted approach, contributing to the successful fabrication of high-rate and ultra-long lifespan dual-ion batteries. Through adding lithium salt into the conventional all phenyl complex electrolyte, not only Li⁺ but also Mg²⁺ can be intercalated into the TNO, implying the intercalation of Mg²⁺ can be activated by the intercalation of Li⁺. Meanwhile, theoretical calculations reveal that the insertion of Li⁺ can significantly improve the electronic conductivity of TNO and reduce the diffusion energy barrier of Mg²⁺ in TNO. Moreover, in-situ Raman and ex-situ X-ray diffraction measurements also indicate the improved structural integrity of TNO with Li⁺ pre-intercalation during cycling. Consequently, such a dual-ion battery system with the TNO cathode and Mg metal anode exhibits a high reversible capacity (243.6 mAh g⁻¹ at 0.1 C) and excellent high-rate cycling stability (capacity retention of 85.1% at 5 C after 2000 cycles)

由于具有两个单位电荷的 Mg ²⁺的电荷密度相对较高，导致固体扩散过程缓慢，严重阻碍了实用镁电池的发展。因此，迫切需要开发新的电荷存储机制来克服固有的动力学障碍。在此，通过电化学Li ^{+嵌入促进方法实现了Mg 2+}在Wadsley-Roth 相TiNb ₂ O ₇ (TNO) 中的快速扩散动力学，有助于成功制备高倍率和超长寿命的双离子电池。通过在传统的全苯基复合电解质中添加锂盐，不仅可以添加Li ⁺，还可以添加Mg ²⁺可以嵌入到TNO中，这意味着Mg ²⁺的嵌入可以被Li ⁺的嵌入激活。同时，理论计算表明，Li ⁺的插入可以显着提高TNO的电子电导率，降低Mg ²⁺在TNO中的扩散能垒。此外，原位拉曼和非原位 X 射线衍射测量还表明，在循环过程中，Li ⁺预嵌入 TNO 的结构完整性得到了改善。因此，这种具有 TNO 正极和 Mg 金属负极的双离子电池系统表现出高可逆容量（243.6 mAh g ^-1在 0.1 C 时）和出色的高速循环稳定性（2000 次循环后，在 5 C 时容量保持率为 85.1%）