A series of Ti-site deficient Li₂CoTi₃O₈-based materials are synthesized by a simple citric-nitrate method. The elemental ratio is determined by X-ray diffraction (XRD) Rietveld refinement and X-ray photoelectron spectroscopy (XPS) measurement. Ti-deficiency is compensated by the increase of Co element valence, resulting in the excess Co³⁺/Co²⁺ and Co⁴⁺/Co²⁺ redox processes during cycling that allows more lithium-ions insertion in the structure, thus endowing the material with a higher theoretical specific capacity. Besides, the Ti-deficiency introduction significantly enhances both the electronic and ionic conductivities and thus the electrode reaction kinetics. The synthesized Li₂CoTi_2.703O₈ anode displays a higher specific capacity (~320 mAh g⁻¹ at 100 mA g⁻¹) and a better rate-capability (185 mAh g⁻¹ at 8000 mA g⁻¹; no capacity decay over 500 cycles). The Ti-deficiency design concept in this work can be extended for the development of other energy storage materials with high energy/power density.

通过简单的柠檬酸－硝酸盐法合成了一系列Ti位点不足的Li ₂ CoTi ₃ O ₈基材料。元素比通过X射线衍射（XRD）Rietveld精炼和X射线光电子能谱（XPS）测量确定。Ti的缺乏通过Co元素价的增加得到补偿，导致过量的Co ³⁺ / Co ²⁺和Co ⁴⁺ / Co ²⁺循环过程中的氧化还原过程允许更多的锂离子插入结构中，从而使材料具有更高的理论比容量。此外，缺乏钛的引入显着提高了电子和离子电导率，从而提高了电极反应动力学。将合成的李₂ COTI _2.703 ö ₈阳极显示更高的比容量（〜320毫安克^-1在100mA克^-1）和更好的速率能力（185毫安克^-1在8000毫安克^-1 ;无容量衰减超过500个周期）。这项工作中的钛缺乏设计概念可以扩展为开发其他具有高能量/功率密度的储能材料。