Li-richl ayered oxides with high capacity are expected to be the next generation of cathode materials. However,t he irreversible and sluggish anionic redox reaction leads to the O 2 loss in the surface as well as the capacity and voltage fading.I nt he present study,asimple gas-solid treatment with ferrous oxalate has been proposed to uniformly coat at hin spinel phase layer with oxygen vacancy and simultaneously realize Fe-ion substitution in the surface.T he integration of oxygen vacancy and spinel phase suppresses irreversible O 2 release,p revents electrolyte corrosion, and promotes Li-ion diffusion. In addition, the surface doping of Fe-ion can further stabilizet he structure.A ccordingly,t he treated Feox-2 %c athode exhibits superior capacity retention of 86.4 %a nd 85.5 %a t1Ca nd 2C to that (75.3 %a nd 75.0 %) of the pristine sample after 300 cycles,r espectively. Then, the voltage fading is significantly suppressed to 0.0011 V per cycle at 2Cespecially.T he encouraging results may play asignificant role in paving the practical application of Li-rich layered oxides cathode.

Silicon monoxide (SiO) has been explored and confirmed as a promising anode material of lithium‐ion batteries. Compared with pure silicon, SiO possesses a more stable microstructure which makes better comprehensive electrochemical properties. However, the lithiation mechanism remains in dispute, and problems such as poor cyclability, unsatisfactory electrical conductivity, and low initial Coulombic efficiency (ICE) need to be addressed. Additionally, more attention needs to be paid on the internal relationship between electrochemical performances and structures. In this review, the different preparation processes, the derived microstructure of the SiOx, the corresponding lithiation mechanism, and electrochemical properties are summarized. Researches about disproportionation reaction which is regarded as a key point and other modifications are systematically introduced. Closely linked with structure, the advantages and disadvantages of various SiOx anode materials are summarized and analyzed, and the possible directions toward the practical applications of SiOx anode material are presented. In a word, from the preparation and reaction mechanism of the material to the modifications and future development, a complete and systematical review on SiOx anode is presented.

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The urgent demand for lithium ion batteries with high energy density is driving the increasing research interest in Si, which possesses an ultrahigh theoretical capacity. Though various modification strategies have been proposed from the aspects of electrolytes, binders, Si‐M alloys, and Si/C composites, the preparation of nano‐structured Si is the first step for industrial application, since it has the potential solve the intrinsic problem of severe volume change during the lithiation/delithiation process. A series of Si nanostructures including 0D (nanoparticles), 1D (nanowires, nanotubes), 2D (thin film), and 3D (porous structure) have been developed and displayed encouraging results. However, it remains a great challenge to realize industrial production with acceptable cost and batch stability. In this review, the preparation development of nano‐structured Si is revisited. After briefly introducing the market situation for nanostructured Si, the fabrication of various kinds of nanostructure Si are introduced, and the corresponding progress including ball milling, magnesium thermal reduction, temple method, chemical vapor deposition, and chemical etching are comprehensively reexamined and compared from the perspective of mechanism, cost, technical maturity, and recent development. Finally, the further directions of nano‐structured Si preparation toward industrial production are deeply discussed. This review of preparation of nanostructured Si helps to pave the way toward commercial application of high energy density Si‐anodes.

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