The limited lithium resource in earth's crust has stimulated the pursuit of alternative energy storage technologies to lithium-ion battery. Potassium-ion batteries (KIBs) are regarded as a kind of promising candidate for large-scale energy storage owing to the high abundance and low cost of potassium resources. Nevertheless, further development and wide application of KIBs are still challenged by several obstacles, one of which is their fast capacity deterioration at high rates. A considerable amount of effort has recently been devoted to address this problem by developing advanced carbonaceous anode materials with diverse structures and morphologies. This review presents and highlights how the architecture engineering of carbonaceous anode materials gives rise to high-rate performances for KIBs, and also the beneficial conceptions are consciously extracted from the recent progress.Particularly, basic insights into the recent engineering strategies, structural innovation, and the related advances of carbonaceous anodes for high-rate KIBs are under specific concerns. Based on the achievements attained so far, a perspective on the foregoing, and proposed possible directions, and avenues for designing high-rate anodes, are presented finally.

Sodium ion batteries (SIBs) are one of the most potential alternative rechargeable batteries because of their low cost, high energy density, high thermal stability, and good structure stability. The cathode materials play a crucial role in the cycling life and safety of SIBs. Among reported cathode candidates, Na 3 V 2 (PO 4) 3 (NVP), a representative electrode material for sodium super ion conductor, has good application prospects due to its good structural stability, high ion conductivity and high platform voltage (∼3.4 V). However, its practical applications are still restricted by comparatively low electronic conductivity. In this review, recent progresses of Na 3 V 2 (PO 4) 3 are well summarized and discussed, including preparation and modification methods, electrochemical properties. Meanwhile, the future research and further development of Na 3 V 2 (PO 4) 3 cathode are also discussed.

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A new kind of hollow carbon nanosphere with an ordered mesoporous shell structure is prepared and demonstrated to have improved ion-diffusion performances.

Li2ZnTi2.9Cr0.1O8 and Li2ZnTi3O8 were synthesized by the liquid phase method and then studied comparatively using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), galvanostatic charge–discharge testing, cyclic stability testing, rate performance testing, and electrochemical impedance spectroscopy (EIS). The results showed that Cr-doped Li2ZnTi3O8 exhibited much improved cycle performance and rate performance compared with Li2ZnTi3O8. Li2ZnTi2.9Cr0.1O8 exhibited a discharge ability of 156.7 and 107.5 mA h g−1 at current densities of 2 and 5 A g−1, respectively. In addition, even at a current density of 1 A g−1, a reversible capacity of 162.2 mA h g−1 was maintained after 200 cycles. The improved electrochemical properties of Li2ZnTi2.9Cr0.1O8 are due to its increased electrical conductivity.

An efficient self-crosslinking procedure to reasonably construct porous shells is reported for the synthesis of yolk–shell Au@microporous carbon nanospheres.

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