Silicon is considered the most promising candidate for anode material in lithium‐ion batteries due to the high theoretical capacity. Unfortunately, the vast volume change and low electric conductivity have limited the application of silicon anodes. In the silicon anode system, the binders are essential for mechanical and conductive integrity. However, there are few reviews to comprehensively introduce binders from the perspective of factors affecting performance and modification methods, which are crucial to the development of binders. In this review, several key factors that have great impact on binders’ performance are summarized, including molecular weight, interfacial bonding, and molecular structure. Moreover, some commonly used modification methods for binders are also provided to control these influencing factors and obtain the binders with better performance. Finally, to overcome the existing problems and challenges about binders, several possible development directions of binders are suggested.

In this work, a flower-like Nb2Se9 material was obtained by a simple oil-phase-assisted synthesis route and used as an anode in lithium-ion and sodium-ion batteries first. It exhibited a high charge capacity (672.35 mAh g–1 at 100 mA g–1), good cycling stability (596.63 mAh g–1 after 250 cycles at 100 mA g–1), and outstanding rate performance (285 mAh g–1 at 5 A g–1) in lithium-ion batteries. Meanwhile, the ex situ X-ray diffraction result reveals that the lithium storage mechanism of Nb2Se9 is the conversion reaction. As an anode for sodium-ion batteries, Nb2Se9 delivered an initial reversible capacity of 342.60 mAh g–1 at the current density of 100 mA g–1 and was stabilized at 230.36 mAh g–1 over 500 cycles after the initial 50 cycles. Excellent electrochemical performance may be attributed to the special micro–nano hierarchical structure of the flower-like Nb2Se9 material, which greatly promotes ion diffusion and provides abundant active sites. These results indicate that flower-like Nb2Se9 is a promising anode material for both lithium-ion and sodium-ion batteries.

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Rechargeable Zn-MnO2 batteries with mild and nearly neutral aqueous electrolytes have shown great potential for large-scale energy storage because of their high safety, low cost, environmental friendliness and high energy...

Hard carbon is one of the most promising anode materials for sodium-ion batteries (SIBs). However, it still faces the obstacle of low reversible capacity. Modifying the carbon skeleton with heteroatoms is an effective method to improve the electrochemical properties of carbon electrodes. Herein, cocklebur fruit, a plant which is rich in natural alkaloids, is selected as the precursor to prepare N/O co-doped hard carbon. The obtained sample pyrolyzed at 1100 °C (H1100) can exhibit 366.07 mAh g À 1 specific discharge capacity and 69.08 % initial coulombic efficiency. The balance between the suitable configuration of N/ O groups and graphitization forms a carbon material with a high sodium-ion storage capability. The storage mechanism is analyzed by cyclic voltammetry (CV), differential capacity (dQ/ dV), galvanostatic intermittent titration technique (GITT), and ex-situ Raman. The results show that the sodium ions are first adsorbed on defect sites, then filled with micropores and embedded in graphite sheets.